April 17, 2017 Essays (328 words) - Construction, Home, House

April 17, 2017 Essay A house is a building that functions as a home , ranging from simple dwellings such as rudimentary huts of nomadic tribes and the improvised shacks in shantytowns to complex, fixed structures of wood, brick, concrete or other materials containing plumbing, ventilation and electrical systems. [1] [2] Houses use a range of different roofing systems to keep precipitation such as rain from getting into the dwelling space. Houses may have doors or locks to secure the dwelling space and protect its inhabitants and contents from burglars or other trespassers. Most conventional modern houses in Western cultures will contain one or more bedrooms and bathrooms , a kitchen or cooking area, and a living room . A house may have a separate dining room , or the eating area may be integrated into another room. Some large houses in North America have a recreation ro om . In traditional agriculture-oriented societies, domestic animals such as chickens or larger livestock (like cattle) may share part of the house with humans. The social unit that lives in a house is known as a household . Most commonly, a household is a family unit of some kind, although households may also be other social groups , such as roommates or, in a rooming house , unconnected individuals. Some houses only have a dwelling space for one family or similar-sized group; larger houses called townhouses or row houses may contain numerous family dwellings in the same structure. A house may be accompanied by outbuildings , such as a garage for vehicles or a shed for gardening equipment and tools. A house may have a backyard or frontyard, which serve as additional areas where inhabitants can relax or eat.

Competitive Strategies for Service Organizations Case Study

Competitive Strategies for Service Organizations Case Study Competitive Strategies for Service Organizations – Case Study Example The paper "Competitive Strategies for Service Organizations" is a brilliant example of a case study on marketing. Nakha, is one of the renowned advertising agencies in Qatar and has been very successful over the years. This is because of the effective strategies that it has been incorporated which can be seen to align with its goals. One of the key aspects of its success is closely related to the effective strategic positioning of its service in the market. The organization provides an assortment of services such as advertisement design, promotional idea, event planning, presentation, research, and survey and consulting. These services are highly attractive to the clients as well as reasonable in terms of prices charged to clients. Hence, the clients are highly satisfied. Thus, the positioning of the products of Nakha can be placed in the quadrant of highly attractive and average priced in the map of market positioning (Botten McManus, 1999). The marketing/service mix contains 7 ele ments, which are commonly known as 7Ps. The first element is the product. The products of Nakha generally consist of advertisement design, event planning, presentation, promotional idea, research, and survey and consulting. The second element is the price, which is highly reasonable and on the average mark for the products of Nakha. Moreover, the element place refers to the offices of Nakha and its availability on television, internet, radio and social media networking sites such as Facebook and Twitter among others. The other element is promotion. The promotional tools that it uses are the social media networking sites including Facebook. Furthermore, People is also a crucial element of the service mix. The dimension of people here implies the proprietors of Nakha, the employees, the clients and the viewers of the advertisements. In addition, another element is the physical evidence. For Nakha, the physical evidence is the video footage, payment receipts, and cheques among others. Last but not least the seventh element is the process. The process that Nakha follows is classified as an information possessing process (Botten McManus, 1999).

Walmart VS. Target Research Paper Example | Topics and Well Written Essays - 1000 words

Walmart VS. Target - Research Paper Example An ancient business analyst, Fernandez, in his publication once depicted that business and humankind are inseparable (98). This shows that the success of business entities and that of humankind are dependant of each other. With the increasing need to sustain human need, numerous business entities have been put in place. The quality and manner of delivery of the products determine the success the organizations realize. It is arguable that human needs are better satisfied when there is free entry and exit into the market. This increases competition, lowering the product’s prices and ensuring better services and service delivery (Chapman 15). In the competition of big box retailers, it is hard for two different firms such as Wal-Mart and Target to achieve the same kind of success in their operation. The first factor that makes Wal Mart to be rated above target is that Wal-Mart provides locally grown products, products that provide energy efficiently, and policies of innovative internal recycling (Kipple, et. al. 174). This has made the company dominate in the market. However, it does not have fair policies for its workers and the wage rate hourly of $10.76 is arguably not impressive. The number of employees at Wal-Mart is around 2.1 million. This proves that the progress of the company is very evident (Murphy 57). Further, the company has expanded to 15 countries with 8,100 retail units. This means that the firm has won a bigger market share than Target. The average revenue recorded by the firm totals $405.6 billion annually. The annual revenue is the commonly used determinant of the company’s success. This means that the firm is successful. From Schwartz Ariel’s article, Sustainability Faceoff: Walmart vs. Target, the number of employees in Target is approximatel y 351,000, which is relatively lower than Wal-Mart. In the entire United States, the firm has initiated stores in 48 states, bringing the retail units to 1,684 stores. This

The Research Proposal Dissertation Example | Topics and Well Written Essays - 2000 words

The Research Proposal - Dissertation Example The presence of such significant number of industries in the region also invariably affect the environment of the region specifically and UK generally. London is also considered as the third command city in the world after New York and Tokyo because of the fact that it is the leading financial hub of the world. The overall population of London is however, mostly employed by the Services sector with less than a million population working in the manufacturing sector. Region’s only substantial manufacturing facility is Ford Dagenham which is also the largest diesel engine manufacturing facility in the world. Though the overall concentration of industry is low in the region however, it can still pose a threat to the environment. This proposed research study therefore aims to assess and explore the impact of industry in greater London on the environment of UK generally and Southern England specifically. Aims and Objectives of the Research The major aim of this research study is to understand and explore as to how the industry of great London impact on the environment of UK and especially the Southern England. ... How industries in great London have an impact on environment? 2. Are there any particular types of industries which are affecting the environment most? 3. Whether regulatory requirements for environment are being met by the industry? A general assessment of the regulatory requirements and the implementation will be undertaken to understand as to whether regulations have any influence on reducing the impact. 4. Does industry is taking efforts to lessen such impact? 5. If yes, what measures have been taken so far in order to contain the damage? These broader aims and objectives will therefore set the overall tone and direction of the research. These research objectives will also allow the researcher to set the overall research questions and hypothesis for this research. Research questions and Hypothesis Following research questions and hypothesis will be constructed for the purpose of this research: 1. Industry has significant impact on the environment. Industry does not have any impac t on the environment? 2. Businesses have put in place appropriate security and risk measures to reduce the impact on environment. There are no significant efforts taken by the industry to reduce the impact on environment. 3. Regulations have been successful in compelling businesses to reduce the harmful impact on environment. Regulations have failed to compel businesses to reduce the harmful impact on environment. Literature Review Greater London region has important significance in the economy of UK and contributed towards the economy to a great extent. It is also however, important to note that the economy of London went through a structural change where the focus was shifted from the manufacturing to services sector. Greater London therefore is still dominated by the firms

Edmund Husserl's Cartesian Meditations (topic upon your own decision) Essay

Edmund Husserl's Cartesian Meditations (topic upon your own decision) - Essay Example Edmund Husserl's is one such philosopher who lived in the more modern world. His work was concerned about phenomena and how the human mind interacts with it. In his book titled Cartesian Meditations: An Introduction to Phenomenology, Edmund Husserl (1960) introduces a number of significant philosophical thoughts. One of the most prominent of these is transcendental phenomenology in which the author gives a new way of analysing phenomena. This kind of thinking looks at phenomena from a different point of view. Although Edmund’s views can be seen as having been inspired by Rene Descartes, a French philosopher and mathematician in the 17th century, Edmund’s theories on phenomena seen to be developed in contrast to what Descartes developed. This can be particularly seen in his transcendental phenomenology which tries to see phenomena in a very different way. Unlike Descartes, Edmund and his school of thought argued that phenomenal can be seen in different dimensions (Husser l, 1960). In fact, Edmund argued that it is possible to take a phenomenal and strip it down to its very essence. In other words, transcendental phenomenology as developed by Edmund postulates that with regard to phenomena, there are those elements which are essential for that phenomenon to exist and there are those which are merely conceptual as conceived by human beings. To be able to separate the essential from the conceptual, Edmund used eidetic reduction. Eidetic Reduction Eidetic reduction is a process by which phenomena can be stripped to its basic essential aspects, without changing it. Eidetic reduction is a conceptual tool that can be used to understand Edmund’s transcendental phenomenology as a way to understand phenomena. Eidetic reduction can be traced back to Descartes. Descartes used a block of wax phenomena as a way to explain the layers of phenomena. For example, the wax can be experienced by the five senses in regard to its shape and the space it occupies, th e smell it exudes, the texture, its opaqueness etc. However, by heating up the block of wax, these properties of the wax can be changed without changing it into another object. In other words, once the wax has been heated up, it will lose its texture, its shape, space and its opaqueness will be changed to transparency. Yet, even after all these characteristics have been changed, the wax will continue to be wax. This means that the block of wax is perceived in two particular ways. The first is one the essential properties of the wax and the second one are the perceived or non essential properties of the wax. Edmund argued that the same can be applied with regard to people’s thoughts. In other words, people’s thoughts can be seen to have both the essential aspects of phenomena and other aspects of phenomena which are more conceptual or perceptual. Using eidetic reduction however, Edmund argues that these thoughts can be stripped down to their basic or essential details. The importance of this kind of stripping is that it leads to a more practical reality, as opposed to when phenomena is understood while it is still shrouded in non-essential properties. Edmund was an essentialist in that he believed that phenomena should be understood in its very essence without being affected by the other factors. However, with regard to ph

Preventing Ethical Problems In Business Philosophy Essay

Preventing Ethical Problems In Business Philosophy Essay What is ethics, and what does it mean to put business and ethics together? What would it mean for a company to do this well? Ethics is a foundation of principles of moral conduct that is based on the philosophies of those involved in a life situation. Therefore, the melding of business and ethics is following these moral guidelines in a business life situation. This can be a slippery slope, as there needs to be an agreement between the moral behavior and the mission of the business, which at times seem to be at odds. It is important to recognize that ethics has a mission it is attempting to accomplish. That mission is not to create the perfect business world but to limit the harm on all stakeholders in their business life situations. What the discipline of business ethics can and must do is to provide an approach for improving the lives of the stakeholders who, with business, live in an imperfect, and sometimes harmful, world. (D. Robin, 2010). So the answer to doing business ethics well requires understanding the possibilities of the harms that could occur for the stakeholders. In order to do that it is v ital to understand the stakeholders and their needs through a stakeholder analysis. This is a helpful way for managers to identify the relevant purposes and consequences in a given case (Freeman, Martin, Werhane Wicks, 2010). In determining what ethical or moral code of conduct will be employed to eliminate or minimize a harm it is a waste of time to establish a code that does not resolve an issue that for any of the stakeholders. If this arbitrary moral code that has no positive or negative effect on any stakeholders is employed it is meaningless. However, if an issue is identified that applies to one or more stakeholders a meaningful moral code can be establish that is useful to all. So an organization that starts first by understanding their stakeholders through a stakeholder analysis and what their needs are will be able to employ meaningful and useful ethics that will allow them limit the harm and do business ethics well. What are the three traditions of ethics, and how do they provide guidance to help inform your managerial decision-making? The three traditions of ethics according to Business Ethics: A Managerial Approach (Freeman, Martin, Werhane Wicks, 2010) are; Actions or means people use to achieve their goals; Agent or persons who are acting in the situation; and Ends or goals that are outcomes of actions. At first glance some comparisons between the traditions would seem to suggest that they are opposites. However, they are really a view of situations from different angles or approaches. They each provide a value in their own right. An actions based approach focuses on the standards that we are using in the decision making process. Is the decision maker following the rules of decency in coming to his moral decision? In an actions based approach it is believed that the means is paramount in the ethical decision that is being made. An actions based approach may be the most useful when stakeholders are going to see the entire process and expect things to be done in a certain way. An Agents based approach does not d eal with how its done nor does it deal with what the the outcome is. Instead it centers on what the decision says about the person making the decision. Does this decision prop up his or her character or does it undermine it? This approach would likely be used when the decision creates a lasting impression that will cause a long term affect of the decision maker or the organization. Finally, an Ends based approach does not look back. It does not concern itself with how it was done or what the decision says about the individual or organization. Instead it looks to the end and assesses the result. Did it yield the positive result that was desired? Focusing on the Ends would be desired when there is little to no harm in how things are done or what the process means but instead what the bottom line becomes. Each of these traditions has its place and its value in providing the guidance to conclude what ethical decision is needed. Before this class discussion in module 1, what was your sense of why organizational ethics like Enron, Arthur Anderson, and Worldcom, happen? I dont like to cast full judgment on people or an organization without completely understanding the entire story. However, I did have a very dim view based on the details of which I was aware. My perspective was that a very large company was taking advantage of the federal government. To mount more trouble on top of it, in the case of Enron, Arthur Anderson who should have held them to a higher standard as an auditor allowed the corruption to continue. The irony of all of this is of course the largest more corrupt offender of all, the federal government, was holding both of these organizations to a standard that they themselves cannot follow in terms of accountability, which is evidenced based on their balance sheet. I certainly did not have an understanding that the 3 traditions of ethics could be applied in this situation. It would seem at some very cloudy level they were applying the Ends tradition. I say this is cloudy in that it brought with it the baggage of corruption to get t o the ends that should have almost obscured the view of it. I would suggest that it would have been more prudent for them to employ the Action, Agent or a combination of these traditions of ethics as it would have likely caused a different outcome. The long term result of this is much more than the harm these organizations caused themselves and their stakeholders. The constraints that often come from harmful situations such as saddling all companies with Sarbanes-Oxley will unnecessarily felt by the business community for years to come. Which factors seem to be most important in diagnosing why bad things happen? What role does the individual, and individual conscience, play in making sure good things happen organizations? To determine within an organization what is the cause of bad ethical decisions it is important to understand the morality and conscience of individuals within the organization and what is driving the decisions that they are making. This includes not only the leadership of an organization but all members from the top down. It can be valuable to look at not only the moral development of the individual but what forces that affect decision making are in play (Freeman, Martin, Werhane Wicks, 2010). First moral development, which is postulated by Kohlberg to be progressive, should be looked at and considered. While not all theorists agree with this approach it can be used as a good model for understanding causation of ethical problems. What is the tendency of individuals in terms of moral development? Is there a tendency to make ethical decisions based on the earlier stages of fear or are they at a point of maturity in this process? Knowing where individuals are in this spectrum can help us understand if it is part of the problem (Forsyth, Donelson R, 1992). Also, if the leadership of the organization is at the early point of the moral spectrum they are going to feed this type of decision making down through the rest of the organization. Understanding not only the individuals moral development but also the leaderships moral development all the way through the organization will help in the diagnosis of the problems. Second, we need to look at the forces in play for decision making. In considering each of the forces discussed in the text it can be assumed that it can be applied at the individual level if we want to understand the problems and want to see good decisions within the organization. Attempting to apply these forces at an organizational level becomes abstract and makes it very difficult to see or directly affect individuals. For example, to see how authority is properly communicated in an organization it is necessary to look at specific examples of this. That is, how a particular individual in authority communicates to other individuals in the organization is important in the making of good ethical decisions. Likewise, how an individual responds to that authority will play into it as well. This can be done with each of the other forces, Distance from Responsibility, Tunnel Vision, Rationalization, External Pressure and Communication Breakdowns. Applying individual notions to each of the se will help in both the diagnosis and resolving to better decision making. Therefore the consideration of the individual conscience both in the diagnosis and the resolution of good decisions is a key element. Read the case, Marge Norman and Miniscribe Corporation, pages 58 67 of your textbook. Provide a summary of this case including the ethical dilemmas and how they were handled in this case. Draw on what you learned in chapters 1 2 as part of your response. The case of Marge Norman and Miniscribe Corporation is a good example of some of the central forces that affect the decision making process, chief of which is the authority force (Freeman, Martin, Werhane Wicks, 2010). In addition, the findings and results suggest the rationalization played a major role in the decisions that were made within the company that caused the downfall of the corporation. Chronologically, the case begins with a company in a difficult position financially. Initially it appeared as if things were moving in a good direction with new leadership, Q. T. Wiles, being very decisive and with a solid influx of investors. One of the dilemmas that initially showed it head was in the area of communication breakdown, as all information was required to be communicated from the very top. In doing this it can be completely controlled as to what is being communicated. This created a fertile ground to allow the story to become whatever the leader wanted it to be. This also ti es into the central force of authority, which played a major role. With Q.T. Wiles being a strong personality with his 13 disciplines it would appear that the company was being lead in the right direction with strong accountability. From the outside this might give the appearance of a solid ethical foundation ensuring those doing the work are being held accountable. As the case continues and we see in the end that cooking of the books had occurred, this suggests that the authority force did indeed play a major role. In addition, the case states that there were many employees involved in the cover up. To have a large number involved it would require an authority figure guiding them and providing rationalizations in the process. There was also the external pressure force placed on the leadership by the accountability structure to come up with the correct numbers, which has the possibility of causing bad decision making. For the scandal to be this successful it had to cause dilemmas fo r all areas of the company. The accountants had to decide if the numbers forced to them should be used. The sales department always watches the numbers closely and would have had to wonder about the inflated numbers. Even the shipping department, who day to day knew what would be going into the boxes, must have faced a moral dilemma. As lies or deceptions occur within a company there is a need for consistency in the store and an escalation tends to occur (Kidwell Martin, 2005). As deceptive dilemmas began to mount with each bad decision more bad decisions were made until it was impossible to conceal as indicated by MiniScribes 13 successful quarters. Looking back had any of the employees overcome the central forces and employed even one of the rationalization tests earlier in the process, the scandal could have been less severe. Far too late, Marge Norman applied the publicity test in a small way by communicating her findings to her supervisor. Had this been done earlier the story would have been different. Had the leadership put themselves in the place of the stockholders, using the reversibility test, it would have brought to the surface the lack of ethics in the decisions. And certainly, using the generalizability test and comparing the situation even to ones personal finances it would be clear that this situation would eventually be found out. The mounting power of the authority force and rationalization along with a failure to apply any of the rationalization tests to the situation proved to be the down fall of MiniScribe. Sadly, this affected not only the company itself but many others in the process.

Asian Continents Rising :: Geology

Sea lion, a scientific mystery Last year ,prince of Monaco visited Russia, where the regional governor in Russia has gifted him with a pair of rare kind of sea lion commonly called as ‘’nerpa’at present the Russian seals called as ‘’nerpa’’ living only in the Baikal lake, which is situated at the center of the Asian continent. Seals are generally living in the coastal area. DNA test has showed that the ancestors of this Russian seals were the ‘’ringed seals’’ which is now living in the northern sea. Therefore the question is how could the ancestors of the Russian seals reached the land locked Baikal Lake which is situated at the center of the Asian continent , hundreds of miles away from the northern sea? Asian continent is rising. The fossils of marine insect called as trilobite which lived on the sea floor, before 50 crore years, now found in all the seven continents. Particularly the fossils of the sea insect, found both in the Russia and china. So it is proved that the continents which are now above the sea level had once been under the sea level. And later rose above the sea level. Similarly, when the Asian continent was submerged under the sea, the ancestors of the Russian seals were able to reach the Epicontinental Sea that covered the Asian continent in the ancient period, and caught in the central land locked Baikal Lake as the Asian continent later rose above the sea level. Still the land masses are rising. And due to this rising of land masses earthquake occurred only in the central region, Similarly the descendants of the northern ringed sea lion also found in the land locked Caspian Sea . So it is proved that the land which is now surrounded the Caspian Sea had once been under the sea level. African continent is rising Similarly, there is a lake called Tanganyika in the east where unique kinds of herring fishes are found. DNA test has showed that the Tanganyika herring fishes are descended from the herring fish, before 5 crore years, which is now living in the Indian Ocean . How the marine fish could reach the inland lake? So it is evident that before five crore years, the eastern part of the African continent had been under the sea level.

Mini Project

CONTENTS 1| ABSTRACT| | 2| ABBREVIATION| | 3| INTRODUCTION TO NC AND CNC| 4| 4| HISTORY| 7| 5| CNC SYSTEM ELEMENTS| 10| 6| WORING ON CNC MACHINES| | 7| BASIC CONCEPTS OF PART PROGRAMMING| 16| 8| TYPES OF CNC MACHINES| 18| 9| PROPERTIES OF CNC MACHINES| 20| 10| DRILLING AND TAPPING ON CNC| 35| 11| APPLICATIONS OF CNC MACHINES| 49| 12| ADVANTAGES AND DISADVANTAGES OF CNC| 51| 13| CONCLUSION| 52| LIST OF FIGURES PAGE NO 1| Hydrotel Milling Machine| 5| 2| Chiron CNC Machine| 5| 3| CNC Lathe Machine| 6| | CNC elements block diagram| 10 | 5| Point to Point tool path| 11| 6| Contour Tool Path| 12| 7| Continuous path tool movements| 18| 8| Continuous path controllers| 19| 9 | Schematic Illustrations of components(a)An open loop(b)A closed loop control| 19| 10| CNC Lathe| 21| 11| CNC Grinders| 21| 12| CNC Drilling| 22| 13| CNC Boring machine| 22| 14| Electrical Discharge Machines (EDM)| 23| 15| Laser cutting machine tools| 23| 16| Flat bed CNC Lathe| 25| 7| Slant bed CNC Lathe| 25| 18| CNC To ol Turrent| 26| | | | | | | | | | | | | 28| Different tools in Drilling machines| 26| 20| Tool Holders| 27| 21| CNC with Fanuc control| 28| 22| CNC setter| 29| 23| Override Speed setter| 31| 24| CNC Backlash| 32| 25| Sensitive Drilling machine| 37| 26| Radial drilling machine| 38| 27| Up-right Drilling machine| 38| 28| Drill materials| 39| 29| Tool nomenclature| 40| 30| Tool holding devices| 41| 31| Various operations of drilling machines| 42| 32| Counter Boring| 43| 33| Counter sunk| 43| 34| Spot Facing| 43| 35| Hands Taps| 46| 36| Holding Devices| 48| 7| Types of Clamps and C- Clamps| 49| 38| Products used in Aerospace Industry| 49| 39| 5 Axis CNC Milling machine| 50| 3. INTRODUCTION TO NC AND CNC Numerical control  (NC) refers to the  automation  of  machine tools  that are operated by programmed commands encoded on a storage medium, controlled manually via hand wheels or levers, or mechanically automated via cams alone. The first NC machines were built in the 1940s and 1950s. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern  computer numerical control  (CNC) machine tools that have revolutionized the  machining  processes.The program is translated into the appropriate electrical signals for input to motors that run the machine. A CNC machine is an numerical control machine with the added feature of an on board computer. The computer is referred to as the machine control unit (MCU). In modern CNC systems, component design is highly automated using  computer-aided design  (CAD) and  computer-aided manufacturing (CAM) programs. The programs produce a computer file that extracts the commands needed to operate a particular machine, and then loaded into the CNC machines for production.Since any component might require the use of a number of different tools-drills, saws, etc. , modern machines often combine multiple tools into a single â€Å"cell†. The Evolution of NC It was i n 1947 when numerical control was born. It began when John C. Parsons of the Parsons Corporation, Traverse City, Michigan, a manufacturer of helicopter rotor blades, could not make his templates fast enough. So, he invented a way of coupling computer equipment with a jig borer. Mr. Parsons used punched cards to operate his digit Ron system. 1949 was the year of another â€Å"Urgent need†. The U. S.Air Material command realized that parts for its planes and missiles were becoming more complex. Also, as the designs were constantly being improved, changes in the drawing were frequently made. Thus, in their search for methods of faster production, an Air Force study contract was awarded to the Parsons Corporation. The servo mechanisms laboratory of the Massachusetts Institute of Technology (MIT) was the subcontractor. In 1951, MIT took over the complete job, and in 1952, the prototype of today’s NC machine, a modified Cincinnati Hydrotel Milling Machine, was successfully d emonstrated.The numerical control was originated at MIT. Fig:1 Fig:2 CNC MACHINES CNC stands for Computer Numerically Controlled. CNC refers to how a machine operates, that is, its basic method of controlling movement, e. g. , a CNC machine uses a stream of digital information (code) from a computer to move motors and other positioning systems in order to guide a spindle or other tooling over raw material. A CNC machine uses mathematics and coordinate systems to understand and process information about what to move, to where, and how fast.Most CNC machines are able to move in three controlled directions at once. These directions are called axes and are given simple names such as X, Y and Z (based on the Cartesian Co-ordinate System). The X axis is always the longest distance a machine or a part of a machine must travel. X may be the movement from front to back, Y the movement from left to right, and the Z is almost always vertical movement (normally the spindle’s positioning movement up and down). Superior Machinery sells many types of CNC Machines, from CNC Horizontals, CNC Verticals to CNC Lathes; they have over 182 CNC Machines to choose from.A CNC machine must be able to communicate with itself to operate. A computer numeric control unit sends position commands to motors. The motors must talk back to the control that, indeed, they have acted correctly to move the machine a given distance. The ability of CNC machines to move in three (or more) directions at once allows them to create almost any desired pattern or shape. All of this processing happens very fast, accurately and consistently. 4. HISTORY Fig:3 In 1775, John Wilkinson- cannon boring machine (lathe). In 1881, Eli Whitney- milling machine. In 1947, Mr.John Parsons began experimenting for using 3-axis curvature data to control the machine tool motion for the production for aircraft components. In 1949, parsons- first NC machine. In 1951, MIT was involved in the project. In 1955, after refine ments NC became available in industry . Today, modern machineries are CNC milling machines and lathes. CNC technology was developed in the United States in the 1950? s for the US Air Force by metalworking machine tool builders. It was a major advance in the ability of machines to faithfully reproduce complex part machining steps more accurately without human intervention or variability.Numerical control (NC) refers to the automation of machine tools that are operated by abstractly programmed commands encoded on a storage medium, as opposed to manually controlled via handwheels or levers, or mechanically automated via cams alone. The first NC machines were built in the 1940s and 1950s, based on existing tools that were modified with motors that moved the controls to follow points fed into the system on punched tape. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern computer numerical control (CNC) machine tools that have revolut ionized the machining processes.In modern CNC systems, end-to-end component design is highly automated using computer-aided design (CAD) and computer-aided manufacturing (CAM) programs. The programs produce a computer file that is interpreted to extract the commands needed to operate a particular machine via a postprocessor, and then loaded into the CNC machines for production. Since any particular component might require the use of a number of different tools-drills, saws, etc. , modern machines often combine multiple tools into a single â€Å"cell†.In other cases, a number of different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case, the complex series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD design. Proliferation of CNC The price of computer cycles fell drastically during the 1960s with the widespread introduc tion of useful minicomputers. Eventually it became less expensive to handle the motor control and feedback with a computer program than it was with dedicated servo systems.Small computers were dedicated to a single mill, placing the entire process in a small box. PDP-8? s and Data General Nova computers were common in these roles. The introduction of the microprocessor in the 1970s further reduced the cost of implementation, and today almost all CNC machines use some form of microprocessor to handle all operations. The introduction of lower-cost CNC machines radically changed the manufacturing industry. Curves are as easy to cut as straight lines, complex 3-D structures are relatively easy to produce, and the number f machining steps that required human action have been dramatically reduced. With the increased automation of manufacturing processes with CNC machining, considerable improvements in consistency and quality have been achieved with no strain on the operator. CNC automatio n reduced the frequency of errors and provided CNC operators with time to perform additional tasks. CNC automation also allows for more flexibility in the way parts are held in the manufacturing process and the time required to change the machine to produce different components.During the early 1970s the Western economies were mired in slow economic growth and rising employment costs, and NC machines started to become more attractive. The major U. S. vendors were slow to respond to the demand for machines suitable for lower-cost NC systems, and into this void stepped the Germans. In 1979, sales of German machines surpassed the U. S. designs for the first time. This cycle quickly repeated itself, and by 1980 Japan had taken a leadership position, U. S. sales dropping all the time. Once sitting in the #1 position in terms of sales on a top-ten chart consisting entirely of U. S. ompanies in 1971, by 1987 Cincinnati Milacron was in 8th place on a chart heavily dominated by Japanese firm s. Many researchers have commented that the U. S. focus on high-end applications left them in an uncompetitive situation when the economic downturn in the early 1970s led to greatly increased demand for low-cost NC systems. Unlike the U. S. companies, who had focused on the highly profitable aerospace market, German and Japanese manufacturers targeted lower-profit segments from the start and were able to enter the low-cost markets much more easily. As computing and networking evolved, so did direct numerical control (DNC).Its long-term coexistence with less networked variants of NC and CNC is explained by the fact that individual firms tend to stick with whatever is profitable and their time and money for trying out alternatives is limited. This explains why machine tool models and tape storage media persist in grandfathered fashion even as the state of the art advances. 5. CNC SYSTEM ELEMENTS A typical CNC system consists of the following six elements. 1 Part program 2 Program inpu t device 3 Machine control unit 4 Drive system 5 Machine tool 6 Feedback system Fig:4 6. WORKING OF CNC MACHINES:CNC machines are Controlled by G and M codes. These are number values and co-ordinates. Each number or code is assigned to a particular operation. Typed in manually to CAD by machine operators. G&M codes are automatically generated by the computer software. The tool or material moves. Tools can operate in 1-5 axes. Larger machines have a machine control unit (MCU) which manages operations. Movement is controlled by a motor (actuators). Feedback is provided by sensors (transducers) Closed loop. Tool magazines are used to change tools automatically. Tool Paths and Cutting   Motions:Tool paths describe the route the cutting tool takes. Motion can be described as point to point, or contouring. Speeds are the rate at which the tool operates e. g. rpm. Feeds are the rate at which the cutting tool and work piece move in relation to each other. Expressed in IPM (inches per minu te) Feeds and speeds are determined by cutting depth, material and quality of finish needed. e. g . harder materials need slower feeds and speeds. Rouging cuts remove larger amounts of material than finishing cuts. Rapid traversing allows the tool or work piece to move rapidly when no machining is taking place.Fig:6 Point to Point Tool path Fig:5Contour ToolPath 1. Point to Point tool paths cut following lines 2. Contour tool paths cut follow surfaces Linear Interpolation: (Point to Point) Linear interpolation consist of a programmed point linked together by straight line Fig:7 Circular Interpolation: (Contour) Circular interpolation is the process of programming arcs and circles. Circular interpolation requires endpoints, a feed rate, a center, a radius, and a direction of movement. Block of Information: When running, a part program is interpreted one command line at a time until all lines are completed.Fig:8 N001 G01 X1. 2345 Y. 06789 MO3 N001:Represents the sequence number of the operation G01: Represents linear operation (tool movement) X12345: Will move the tool or table 1. 2345 in. a positive direction along the X axis Y6789:Will move the tool or table 0. 6789 in. along the Y axis M03:Turns spindle on clockwise Commands, which are also referred to as blocks, are made up of words which each begin with a letter address and end with a numerical value. Each letter address relates to a specific machine function. â€Å"G† and â€Å"M† letter addresses O-Program number (Used for program identification)N-Sequence number (Used for line identification) G-Preparatory function X-X axis designation Y-Y axis designation Z-Z axis designation R-Radius designation F-Feed rate designation S-Spindle speed designation H-Tool length offset designation D-Tool radius offset designation T-Tool Designation M-Miscellaneous function G- CODES (Preparatory Functions) which cause some movement of the machine table or head. G00 – Rapid Movement G01- Linear Interpo lation (movement) G02- Circular Interpolation, CW G03- Circular Interpolation, CCW G17 -XY Plane,G18- XZ Plane,G19 -YZ Plane G20/G70 -Inch unitsG21/G71 -Metric Units G40- Cutter compensation cancel G41 -Cutter compensation right G43- Tool length compensation (plus) G43- Tool length compensation (plus) G44- Tool length compensation (minus) G49-Tool length compensation cancel G80-Cancel canned cycles G81-Drilling cycle G82-Counter boring cycle G83-Deep hole drilling cycle G90-Absolute positioning G91- Incremental positioning M-CODES (Miscellaneous) which turn ON or OFF different functions M00 -Program stop M01 -Optional program stop M02 -Program end M03- Spindle on clockwise M04 -Spindle on counterclockwise M05- Spindle stop M06- Tool change . BASIC CONCEPTS OF PART PROGRAMMING Part programming contains geometric data about the part and motion information to move the cutting tool with respect to the worpiece. Basically, the machine receives instructions as a sequence of blocks contain ing commands to set machine parameters; speed, feed and other relevant information. A block is equivalent to a line of codes in a part program. N135 G01 X1. 0 Y1. 0 Z0. 125 T01 F5. 0 These define: N135-Block number G01-G codes X1. 0, Y1. 0, Z0. 125-Coordinates T01-Tool number F5. 0-Special function Programming Methods Automatically Programmed Tools (APT):A text based system in which a programmer defines a series of lines, arcs, and points which define the overall part geometry locations. These features are then used to generate a cutter location (CL) file. Computer Aided Machining (CAM) Systems-Computer Aided Design (CAD) Systems: CAD/CAM systems allow for rapid development and modifying of designs and documentation. The 3D geometric model produced becomes a common element for engineering analysis (FEA), machining process planning (including CNC part programming, documentation (including engineering drawings), quality control, and so on.Drives of CNC machine tool Hydraulic actuator – high power machine tool Stepping motor – small machine due to limited power and torque DC motor – excellent speed regulation, high torque, most widely used. 8. PROPERTIES OF CNC MACHINES Based on Motion Type: Motion control – the heart of CNC: Point-to-Point or Continuous path Based on Control Loops: Open loop or Closed loop Based on Power Supply: Electric or Hydraulic or Pneumatic Based on Positioning System: Incremental or Absolute Point-to-Point Tool Movements: Point-to-point control systems cause the tool to that point only.The tool is not in continuous contact with the part while it is moving. Examples: drilling, reaming, punching, boring and tapping. Fig:9 Continuous-Path Tool Movements : Continuous-path controllers cause the tool to maintain continuous contact with the part as the tool cuts a contour shape. These operations include milling along any lines at any angle, milling Fig:10 Arcs and lathe turning. Loop Systems for Controlling Tool Movem ent: Schematic illustration of the components of (a) an open-loop and (b) a closed-loop control system for a CNC machine. 9. TYPES OF CNC MACHINES * Lathe Machine * Milling Machine Drilling Machine -The bench drill -The pillar drill * Boring Machine * Grinding Machine CNC Mills: These machining centers use computer controls to cut different materials. They are able to translate programs consisting of specific number and letters to move the spindle to various locations and depths. Used to make 3D prototypes, moulds, cutting dies, printing plates and sights. CNC Lathes: They cut metal that is often turning at fast speeds. CNC lathes are able to make fast ,precision cuts using Indexable tools and drills with complicated programs. Normally, they cannot be cut on manual lathes.They often include 12 tool holder sand coolant pumps to cut down on tool wear. Fig:11 CNC Grinders: Grinding metal process uses a coated wheel that slowly removes metal to create a part. Through the years, grinding was done on a manual machine, but with the advent of CNC technology, the grinding process has advanced . Fig:12 CNC DRILLING: Drilling is commonly used for mass production. The drilling machine (drilling press) is used to create or enlarge holes. The bench drill: For drilling holes through raw materials such as wood, plastic and metal The pillar drill: A larger version that stands upright on the floor.As the bench drill, it can be used to drill larger pieces of materials and produce bigger holes. Fig:13 CNC Boring: Process of enlarging an existing hole or internal cylindirical surface. This can be accomplished on a lathe or a machine tool specifically designed for the process, such as a horizontal boring machine. Fig:14 Electrical Discharge Machines (EDM): Wire EDM machines utilize a very thin wire (. 0008 to . 012in. ) as an electrode. The wire is stretched between diamond guides and carbide that conduct current to the wire and cuts the part like a band saw.Material is removed by the erosion caused by a spark that moves horizontally with the wire. Fig:15 Laser Cutting Machines: The machine utilizes an intense beam of focused laser light to cut the part. Material under the beam experiences a rapid rise in temperature and is vaporized. Laser cuts with a minimum of distortion, no mechanical cutting forces. Specific tools to perform different Operations: Fig:16Fig:17 CNC lathe machine tool turret is part of the CNC machine where all tooling is mounted. CNC lathe tool turret has an integral Disk like part (Tool turret disk) on which all the tools are mounted.CNC lathe tool turret is mounted on the x-axis carriage. Fig:18 Slant Bed CNC Lathe / Flat Bed CNC Lathe On some CNC lathe machines x-axis carriage with the tool turret is located behind the spindle (such cnc lathe machines are called  slant bed cnc lathe machines) and on other cnc lathe it is located at the front (as normal lathe machines) such cnc lathe machines are called  flat bed cnc lathe machine. T he below is a Slant Bed CNC Lathe Machine. Fig:19 Fig:20 CNC Lathe Tool Turret Tool Capacity: Tool capacity for cnc lathe machines varies machine to machine.Small CNC lathe machines normally comes with a tool turret capacity of 4 or 8 tools stations. Bigger and  heavy CNC lathe machines tool turrets are big and heavy and accordingly will hold more tools such as 12 or more. Fig:21 Tool Holder: Tool holder is the actual part which fastens   the tool to the cnc lathe tool turret Disk. Tool holder size also depends upon the cnc lathe tool turret size, heavy CNC late machine tool turret comes with with big bore for tool holders such as 50 mm diameter. For the small tool turret this might be 40 mm diameter or, less to suit the tool to hold.Fig:22 CNC Lathe Tool Turret Rotation CNC lathe tool turret rotates with the cnc program commands. Normally a letter â€Å"T† is used to call a tool in the working position. The tool rotation is dependent on cnc lathe machine. Some cnc lathe tool turret rotate in one direction (CW or CCW ). Some cnc lathe tool turret rotates both directions, such tool turret direction is optimized for the nearest tool station. Some cnc lathe give full control over tool call up, you can call by optimized direction or you can call tool by rotating tool turret by CW direction or CCW.Tool Offset in CNC Lathe with Fanuc Control Fig:23 There are variety of cnc machines in the market, and almost every cnc machine in a  cnc workshop  has different kind of cnc machine controls if controls are not different they might have different versions of the same cnc machine control. As the operating of different cnc machines controls is very much different from one another the same way  Tool Offsetting  is very much different. Here I will discuss the cnc tool measurement on Fanuc. Tool Offset Setting on Fanuc TCSome cnc machines has some kind of built-in mechanism of tool-offsetting, this built-in mechanisn of tool-offsetting makes adding new tool s are changing existing tools a breeze, because you just tie-up the tool in the tool-post on the  cnc machine tool-turret  and just perform the procedure the cnc machine manufacture has given in the cnc machine operating and setting manual. The  Fanuc  controls such as Fanuc TC has this capability, Just tie up tool in the tool turret and perform a simple procedure and everything is done. The tool offsetting procedure might be different from version to version, But on Fanuc TC this procedure is simple as under.For tool offsetting of a new tool just tie up the tool in the tool post and in  MDI (Manual Data Input) Mode  call up the tool in the working position by entering the command T1, the T is for tool call up and 1 is tool number if you have your tool on another position you might change that with that tool number. Now change the cnc machine to Jog Mode and touch the tool cutting point to the finished component (already gripped in cnc machine jaws) face and bring the To ol-Geometry page and enter under the tool number the command MZ0 this command will clear any previous values and will measure the current tool’s tool-offset in Z-axis.Now touch the tool to a  known-diameter  on the component and again in the tool-geometry page enter the command MX50 you can enter the measured diameter value instead of 50. This way now we have calculated the tool-measurement on the Fanuc TC cnc machine control. CNC Dry Run Invaluable Tool for CNC Setter: Fig:24 It shows the power and the flexibility the cnc machine manufacturers and cnc control manufacturers give a  cnc machine setter  by integrating the Dry Run  on cnc machines. On some cnc machines the Dry Run is added as a  CNC Machine Mode  like Fanuc.On Fanuc cnc control you just select the Dry Run mode and cnc machine is now in Dry Run Mode. Introduction of Dry Run for CNC Machines Setting a new component on a cnc machine is not an easy job. You have to go through many important tasks like cnc machine zero offsetting (cnc machine shift value setting),tool offsetting of tools  used on cnc machine etc. Now if you have completed these all tasks, now comes the time to run the cnc program for the first time, A really crucial and time consuming cnc task. A small negligence might be cause of an accident on cnc machine (tool breakage etc. . To make the first run easy and safe the cnc machine manufacturers and cnc control manufacturers provide us a way by which we can easily control the tools feed with  feed override. So now the cnc setter is a bit easy because he can now run all the tools with a  Safe Feed. Now cnc setter easily can lower the tool feed when he feels the tool is entering a bit danger zone, and easily can increase the tool feed (to a rapid feed) when the tool is away from the component (so the time not go wasted with lower feed when tool is away from component).In Dry Run all the cnc blocks whether those are starting with G00 or G01 and other  G-code  like G02/G03 run with the same feed, which is controlled through Feed Override. On Fanuc the feed override is controlled through  Handwheel  after feed override button press, and there also exists a Rapid Feed Button which if pressed during Dry Run Mode the cnc machine program block will run with Rapid Feed. One point must be cleared for Fanuc control is that feed override also works in  Auto Mode and Single Block Mode  but in such modes the feed override only controls G01/G02/G03 like G-code.But feed override will not control the G00 (Rapid Traverse). But in Dry Run Mode all the cnc program will run with the feed which is controlled through Feed Override. An introduction to cnc machine speed override and feed override controls and safety instructions which must be adhere to while working with cnc machine feed and speed override. CNC Machine Speed Override / Feed Override Introduction Normally you program the speed and feed this way, N10 G97 S1000 G95 F0. 3 Fig:25Now for on e reason or other you want to increase or decrease the speed or feed of the cnc machine  for some time, you definitely have a way to just alter the  cnc machine program, but there is one more suitable solution the Feed Override and Speed Override Controls. The feed override and speed override are  the most suitable and handy way to control the  cnc machine feed and speed through cnc control panel. You control the speed and feed in percentage. When the feed override  is 100% the actually feed  which is programmed will be active.But if the feed override  is 50% then the feed  will decrease by that ratio, now the machine tools will run with 50% of feed. So if you  have programmed 0. 5 mm/rev feed then with 100% the 0. 5 will be active, but for 50%  feed override the actually tool feed will be 0. 25 mm/rev. The same rule applies for speed override, for 100% the actual programmed speed will be active and spindle will revolve  with the actual programmed speed. But  at 50% speed  override the spindle speed will drop by 50%. Feed Override Speed Override Minimum Maximum Values: Normally you can control speed override and feed override from 0% to 120%.At 0% speed override the spindle will stop rotating, and at 0% feed override the tool will stop working ( the tool will be stationary ). No doubt  120% feed  override and speed override is just  safe. But some cnc machines give even more flexibility I  have worked on a cnc machine which has its feed override 0% to 200%. Normal cnc machine has just 0% to 120% feed  override and speed override. Speed Override and Feed Override Safety Precautions Whenever handling the speed override and feed override always think about safety, safety of yourself, tool, machine, component and your surroundings.Never try to use the speed override and feed override if you don’t need it. Because when cnc programs are made the speed and feed is properly set for the machined component. The increase in feed or speed might break insert or even tool. CNC Backlash CNC Troubleshooting, In this category we will see the cnc machine from a different view (cnc machine maintenance), your feedback will really matter, and I hope you will share you knowledge and experience. I will talk about the  CNC  Backlash  which is found in cnc machine axis. * what is cnc backlash, * cnc backlash causes, * when to worry about cnc backlash, how to measure backlash, * How to resolve and compensate cnc backlash through hardware and cnc control software. Fig:26 *What is CNC Backlash? CNC Backlash is any kind of play which is found in cnc machine axis. or you might say, CNC Backlash  is non-movement of the cnc axis which occurs on axis reversal. *Causes of CNC Backlash? This play (backlash) might be due to * Clearance which is kept in mechanical parts to reduce friction. * As mechanical parts get loose with time. * As with time mechanical parts keep moving and rubbing each other and after long time they l ose their actual shape and size. CNC Backlash Is already there A cnc machine axis move due to their  Lead Screw  and  Lead Screw Nut. There is always kept a very minor backlash in the lead screw and lead screw nut to reduce damage and wear. *CNC Backlash When to Worry It is good if your cnc machine axis backlash is near 0. 0001? but not always possible, so 0. 0003? to 0. 0004? is acceptable. But if the amount of play in the lead screw and nut crosses this limit then there is the time to worry, and call up you mechanical maintenance guys. CNC Backlash How to Measure?CNC machine backlash can be measure with a  Dial Indicator  attached to an Adjustable Stand. Put the stand on the cnc bed and direct the needle (plunger) of the dial indicator towards the axis which you want to measure. 1. Set the dial needle to 0. 0mm (zero). 2. Now move the axis in one direction 0. 5mm. Dial indicator should show 0. 5mm travel. 3. Now reverse the same axis 0. 5mm. If your dial indicator now go es back to 0. 0mm, then everything is okay. But otherwise, if on reversal the dial lags behind, then the amount the dial lags behind is the backlash.CNC Backlash How to Resolve? ( Backlash Compensation ) Now you have two choices the hardware way and software way to resolve cnc backlash. You first better choose the hardware way, because normally backlash is due to lead screw or lead screw nut wear, so better resolve the issue by tightening them a bit if they are loose than required, there are plenty of other hardware ways to cope with backlash. CNC controls also give us the ability to control (compensate) cnc backlash through their parameters. CNC Backlash Compensation through CNC Control Parameters How Much Successful?The better advice is that you resolve the issue by changing the lead screw (if possible) or lead screw nut, or just tightening them if they are loose might work, but otherwise CNC control parameters can be changed to compensate backlash, the cnc lathe machine I work on with fanuc control has the 0. 012mm set in its parameters as the backlash compensation for x-axis and z-axis. So such values can be changed to resolve the backlash issue. 10. DRILLING AND TAPPING ON CNC MACHINES Drilling is the operation of producing circular hole in the work-piece by using a rotating cutter called DRILL.The machine used for drilling is called drilling machine. The drilling operation can also be accomplished in lathe, in which the drill is held in tailstock and the work is held by the chuck. The most common drill used is the twist drill. Drilling Machine It is the simplest and accurate machine used in production shop. The work piece is held stationary ie. Clamped in position and the drill rotates to make a hole. Types 1) Based on construction: Portable, Sensitive, Radial, up-right, Gang, Multi-spindle 2) Based on Feed: Hand driven ,Power driven Components of drilling machine:Spindle The spindle holds the drill or cutting tools and revolves in a fixed position in a sleeve. Sleeve The sleeve or quill assembly does not revolve but may slide in its bearing in a direction parallel to its axis. When the sleeve carrying the spindle with a cutting tool is lowered, the cutting tool is fed into the work: and when it’s moved upward, the cutting tool is withdrawn from the work. Feed pressure applied to the sleeve by hand or power causes the revolving drill to cut its way into the work a fraction of an mm per revolution. ColumnThe column is cylindrical in shape and built rugged and solid. The column supports the head and the sleeve or quill assembly. Head The head of the drilling machine is composed of the sleeve, a spindle, an electric motor and feed mechanism. The head is bolted to the column. Worktable The worktable is supported on an arm mounted to the column. The worktable can be adjusted vertically to accommodate different heights of work or it can be swung completely out of the way. It may be tilted up to 90 degree in either direction, to al low long pieces to be end or angle drilled. BaseThe base of the drilling machine supports the entire machine and when bolted to the floor, provides for vibration-free operation and best machining accuracy. The top of the base is similar to the worktable and may be equipped with t- slot for mounting work too larger for the table. Hand Feed The hand- feed drilling machines are the simplest and most common type of drilling machines in use today. These are light duty machine that are operated by the operator, using a feed handled, so that the operator is able to â€Å"feel† the action of the cutting tool as it cuts through the work piece. These drilling machines can be bench or floor mounted.Power feed The power feed drilling machine are usually larger and heavier than the hand feed ones they are equipped with the ability to feed the cutting tool in to the work automatically, at preset depth of cut per revolution of the spindle these machines are used in maintenance for medium du ty work or the work that uses large drills that require power feed larger work pieces are usually clamped directly to the table or base using t –bolts and clamps by a small work places are held in a vise. A depth –stop mechanism is located on the head, near the spindle, to aid in drilling to a precise depth.Sensitive or Bench Drilling Machine * This type of drill machine is used for very light works. Fig. 1 illustrates the sketch of sensitive drilling machine. * The vertical column carries a swiveling table the height of which can be adjusted according to the work piece height. * The table can also be swung to any desired position. * At the top of the column there are two pulleys connected by a belt, one pulley is mounted on the motor shaft and other on the machine spindle. * Vertical movement to the spindle is given by the feed handle by the operator. * Operator senses the cutting action so sensitive drilling machine.Fig:27 Up-Right Drilling Machine * These are medium heavy duty machines. * It specifically differs from sensitive drill in its weight, rigidity, application of power feed and wider range of spindle speed. Fig. 2 shows the line sketch of up-right drilling machine. * This machine usually has a gear driven mechanism for different spindle speed and an automatic or power feed device. * Table can move vertically and radially. * Drill holes up to 50mm Fig:28 Radial Drilling Machine * It the largest and most versatile used for drilling medium to large and heavy work pieces. Radial drilling machine belong to power feed type. * The column and radial drilling machine supports the radial arm, drill head and motor. Fig. 3 shows the line sketch of radial drilling machine. * The radial arm slides up and down on the column with the help of elevating screw provided on the side of the column, which is driven by a motor. * The drill head is mounted on the radial arm and moves on the guide ways provided the radial arm can also be swiveled around the co lumn. * The drill head is equipped with a separate motor to drive the spindle, which carries the drill bit.A drill head may be moved on the arm manually or by power. * Feed can be either manual or automatic with reversal mechanism. Drill Materials The two most common types are 1. HSS drill- Low cost 2. Carbide- tipped drills – high production and in CNC machines Other types are: Solid Carbide drill, TiN coated drills, carbide coated masonry drills, parabolic drills, split point drill. Fig. 4 shows various types of drills. Drill fixed to the spindle Fig:30 Tool Nomenclature: Fig. 31 Nomenclature of twist drill Tool holding devices Fig. 7 and Fig. 8 shows the different work holding and drill drift device.The different methods used for holding drill in a drill spindle are * By directly fitting in the spindle hole. * By using drill sleeve * By using drill socket * By using drill chuck Fig:32 Drilling operations: Operations that can be performed in a drilling machine are * Drillin g * Reaming * Boring * Counter boring * Countersinking * Tapping Drilling: It is an operation by which holes are produced in solid metal by means of revolving tool called ‘Drill’. Fig. 9 shows the various operations on drilling machine. Reaming: Reaming is accurate way of sizing and finishing the pre-existing hole.Multi tooth cutting tool. Accuracy of 0. 005mm can be achieved. Boring: Boring is a process of enlarging an existing hole by a single point cutting tool. Boring operation is often preferred because we can correct hole size, or alignment and can produce smooth finish. Boring tool is held in the boring bar which has the shank. Accuracy of 0. 005mm can be achieved. Fig. 33 Various operations on drilling machine Counter Bore :- This operation uses a pilot to guide the cutting action to accommodate the heads of bolts. Fig. 10 illustrates the counter boring, countersunk and spot facing processes. Countersink:-Special angled cone shaped enlargement at the end of the hole to accommodate the screws. Cone angles of 60 °, 82 °, 90 °, 100 °, 110 °, 120 ° Fig. 34 Counter boring, countersunk and spot facing Drilling  machines are tools that have a rotating, cutting component at one end that bores holes into different materials. There are several types of  drilling  machines that may be used for a wide variety of purposes, including woodworking, construction,  masonry, metalworking, medicine, oil  drilling, and many other fields. Common drills include the hand drill, push drill, pistol-grip drill, hammer drill, and  drill press.In addition to making holes, drills are often used to push screws into wood, metal, plastic, rock, or composites. The hand drill and push drill are both manually operated  drilling  machines that have been largely replaced by power drills. A hand drill works by turning a crank that rotates gears, which cause the chuck to turn. The chuck is the component of the  drilling  machine  that holds the bit, or the end cutting piece. The push drill is a skinny tool resembling a screwdriver with a handle that can be pushed down on a threaded shaft, or a pole with helical ridging.As the handle is pushed down along threading, the shaft, chuck, and bit spins downward, much like pumping a toy metal top. Pistol-grip drills are the most commonly used  drilling  machines. These are corded electric drills that are typically shaped roughly like a pistol, with a trigger switch that starts a motor inside the drill. The motor causes the chuck and bit to spin in continuous revolutions. These drilling  machines may be used to make holes for bolts or other purposes, to push screws into wood, plastic, or other materials, and to bore countersinks.A  countersink  is a screw-shaped hole that is made before the screw is drilled in, preventing splintering or pulling of the plastic or wood around the head of the screw. A pistol-grip drill is also available in a battery-powered, cordless version , though they are usually more expensive. There are many different types of this drill and several indications for use. It is also possible to adapt the drill with an attachment, such as sanding or sawing components. A hammer drill, also called a rotary hammer, is similar to a pistol-grip drill, but also applies a punching motion to complement the rotational action of the bit.This hammering, forward force makes it useful for tougher materials, such as concrete or stone, that standard electric drills cannot cut through. For softer materials, however, the hammer drill may apply excessive force and a standard drill may be a better choice. A drill press is a type of drill that may stand on the floor or be mounted on a workbench. The base of the  machine  is bolted to the table or floor and a column rises up from the base to support the back of the head of the drill. The column also supports a table that can be adjusted in height between the head and the base.The spindle, a metal com ponent that holds the chuck and drill bit, extends downward from the front of the head, parallel to the column. A larger distance between the spindle and column allows wood with a larger width to be drilled. An â€Å"on† switch triggers the spindle to spin and levers attached to the head of the drill press move the spindle and chuck to move up or down. These  drilling  machines are suited for accurate  drilling, because the bit is fixed and the work can be secured to the table with clamps or a vise. ————————————————- Types Of Drill BitsDrill bits are tools used in making cylindrical holes. Various types of drill bits are designed for different uses. Drill bits are equipments or tools that are used in making cylindrical holes. Drill bits can also be referred to as a drilling machine. Drill bits are available in various drill types such as metal drills, gun dril ls, screw machine drills, core drills, step drills, spade drills, forstner drills, masonry drills, dental or surgical drills, wood bits, twist drills, drill blank taper drills and much more. They are designed to cut while doing a clockwise rotating motion. Several drill bits are coolant fed.They contain a channel or hole for directing the coolant fed near to the cutting edges. The split point drill heads of drill bits are used for chip clearance and for excellent centering. Drill bits can also be used in cutting aluminum, general-purpose metals, brass, copper, bronze, ceramic, and plastic, stainless steel, steel, wood, titanium and hardened materials. Various types of drill bits are designed for different uses. Listed below are some types of Drill Bits. Twist Drill: It drills holes in plastic, metal and wood. This drill is currently produced with a width covering a range from 0. 5 millimeters to 100 millimeters while its length is around 1000 millimeters. The most usual twist drill has a tip angle of 118 degrees. This is a proper angle for an extensive array of job. It also has a long series drill for extended length twist drills. It is not advisable to drill deep holes using this twist drill. Diamond Drill Bit: This particular drill is used in the bathroom for updating or remodeling. It is also used in redesigning your kitchen decoration. Furthermore, it is used on ceramic, glass, tile, limestone, stained glass, marble, fiberglass, porcelain, stone, slate and porcelain tile.When using this drill, the main concern is to obtain water at the edge of the drill bit. Drilling fiberglass may be done with or without water but make sure that the fiberglass has ample amount of water just to get the drill wet. Indexable Drill Bit: This provides an excellent performance in making short-hole drillings. Stainless steel is drilled 3x in diameter and only a short-hole must be done. Listed below are some other types of drill bits Adjustable Bit: This is built with a changeabl e cutter blade to bore holes of various sizes. It is also used for drilling gaps for wiring or piping.Around-the-corner bit: It is used to cut arched holes that are stretched in corners with a diagonal cutting surface. Auger Bits: This drill creates drill holes in wooden materials. The drill ends have a screw head so that the bits may be self fed. Brad-point drill: This drill looks almost the same as the usual bits but it has sharpened point to make wood drilling a lot easier. This drill has cleaner holes other than spade bits. Counterbore: The drill allows a screw to be driven under the wood outside. The holes that are drilled may be filled with a plug or wire.Drill Saw Bit: It is used to cut holes such as wood and metal and can enlarge current holes. Countersink: A drill that has an angled tip design that forms a â€Å"slump† in the screw head. Fly cutter: This one is often used to cut circles in wood and other soft metals. The diameter of circles may be adjusted by changin g the cutter blade setting. Hole saw: It cut holes from one to six centimeters in diameter and has a center bit for directing the cutting blade edge of the saw. Reamer bit: The tapered bit of reamer may be used on existing holes rather than to enlarge holes.Screw pilot bit: This beautiful bit is used for drilling body holes. A pilot hole is used along with the countersink. Wire Brushes: It use to remove rust and to clean up metal and is available either as a wheel or a cup with wire brush. Plastic bit: This is designed with a tip so as to prevent splintering when drilling plastic. It is important to reduce the speed and slowly drill the other side of the plastic. Plug cutter: Use this to remove cylindrical shapes from the wood. It covers the screw using a small cylindrical plate. Tapping:- Tapping is the process by which internal threads are formed.It is performed either by hand or by machine. Minor diameter of the thread is drilled and then tapping is done. Fig. 11 show the tapping processes. Fig. 35 Hand taps and tapping process using tap wrench Fig. 36 Various operations performed on drilling machine Work Holding Devices 1. Machine Table Vice: The machine vice is equipped with jaws which clamps the work piece. The vice can be bolted to the drilling table or the tail can be swung around swung around. Fig. 13 shows the standard and swivel vice. The swivel vice is a machine wise that can be swivel through 360 ° on a horizontal plane. Fig:37 1.Step Blocks These are built to allow height adjustment for mounting the drilling jobs and are used with strap clamps and long T-slot bolts. 2. Clamps These are small, portable vises , which bears against the work piece and holding devices. Common types of clamps are C-clamp, Parallel clamp, machine strap clamp, U-clamp etc.. Fig. 14 shows the correct and incorrect methods of mounting the work piece. Fig:38 11. APPLICATION OF CNC MACHINES ? cutting ? drilling ? milling ? welding ? boring ? bending ? spinning ? pinning ? gluing ? sewing ? routing Its application in some industries like -Automotive Industry Aerospace Industry -Machinery Industry -Electrical Industry -Instrumentation Industry Automotive Industry Different Products Fig:39 Aerospace Industry Aircraft Turbine Machined by 5-Axis CNC Milling Machine Fig:40 12. ADVANTAGES AND DISADVANTAGES OF CNC -Ease of Use ? CNC machines are easier for beginners ? Operation of several CNC machines at same time ? Some CNC machines don’t need any operator indeed call their operator in case of the emergencies. High Efficiency ? operate almost continuously 24 hours a day, 365 days a year. Expanding Options ? Expand the machine's capabilities with SoftwareChanges and updates. No Prototyping ? new programmers provide elimination build a prototype, save time and money. Precision ? Parts are identical to each other. Reduce Waste ? Reduce waste as errors allows minimize wasted Material. Disadvantage of CNC Machines Cost CNC machinery: ? costs quite a lot m ore than conventional machinery. ? Does not eliminate the need for expensive tools. ? Expensive to repair. 13. CONCLUSION CNC machines which are applicable any type of processing. manufacturing anything is identical in shorter time. CNC machines provide many advantages. Many industries prefer using CNC machines.

5 Ways to Reduce Use of Prepositions

5 Ways to Reduce Use of Prepositions 5 Ways to Reduce Use of Prepositions 5 Ways to Reduce Use of Prepositions By Mark Nichol Prepositions, words that indicate relations between nouns, pronouns, and verbs (mostly small ones like for, in, of, on, to, and with but sometimes more substantial, as in the case of beneath or between), are often integral to a sentence, but writers can clutter sentences by being overly dependent on them. Here are five strategies for minimizing the number of prepositions you use: 1. Eliminate Prepositions by Using Active Voice Shifting from passive voice to active voice, as in the revision of â€Å"The watch was obviously designed by a master craftsman† to â€Å"A master craftsman had obviously designed the watch† takes a preposition out of action. (But take care that the inversion of the sentence structure doesn’t incorrectly shift emphasis or diminish dramatic effect.) 2. Substitute an Adverb for a Prepositional Phrase In the writer’s toolbox, adverbs are stronger tools than prepositional phrases. Revision of the sentence â€Å"The politician responded to the allegations with vehemence† to â€Å"The politician responded vehemently to the allegations† strengthens the thought and deletes the weak preposition with. 3. Use a Genitive in Place of a Prepositional Phrase An easy test to help reduce the number of prepositions is to search for the genitive case, or a possessive form: If a sentence could use the genitive case but doesn’t, revise the sentence. For example, â€Å"She was disturbed by the violent images in the movie† gains more impact (and loses a preposition) by reversing the sentence’s subject and object: â€Å"She was disturbed by the movie’s violent images.† (Combine this strategy with a shift from passive voice to active voice, and you jettison two prepositions and further strengthen the statement: â€Å"The movie’s violent images disturbed her.†) Another use of this technique is to revise a phrase including a reference to a location within a location, as in â€Å"the Museum of Modern Art in New York City,† which can be more actively and efficiently rendered as â€Å"New York City’s Museum of Modern Art.† 4. Omit Prepositions by Eliminating Nominalizations Writers and editors aid clarity and conciseness by uncovering nominalizations, otherwise known as buried, or smothered, verbs. In doing so, they also negate the need for a preposition. For example, the sentence â€Å"Their attempt to provide a justification of the expense was unsuccessful,† simplified to â€Å"Their attempt to justify the expense was unsuccessful,† not only transforms the verb+article+nominalization clump â€Å"provide a justification† into the streamlined verb justify but also makes of unnecessary. (I originally wrote â€Å"but also makes the use of of unnecessary,† but then deleted the superfluous phrase â€Å"the use of† and thereby deleted a preposition.) 5. Delete Prepositional Phrases Prepositional phrases (preposition+article+noun) provide context, but they’re not always necessary. In a sentence like â€Å"The best outcome for this scenario would be an incremental withdrawal,† note whether the meaning is clear without the phrase, and if so, strike it out: â€Å"The best outcome would be an incremental withdrawal.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Grammar category, check our popular posts, or choose a related post below:75 Synonyms for â€Å"Angry†Dawned vs. DonnedEach vs. Both

College Valentines Day Survival Guide

College Valentines Day Survival Guide Valentines Day and college can make a fantastic or awkward mix. Make the most of your situation by enjoying yourself, enjoying the day, and if applicable enjoying the time with a significant other. Conversely, of course, you can find information on making the most of being single. Valentines Day doesnt have to be a celebration only for those already coupled up! If Youre Single Being single on Valentines Day doesnt have to mean being awkward or having a funky night. There are multiple ways to ensure you still have a great Valentines Day ​without a significant other.​​ If You Have a Crush on Someone Have a crush on someone? Not sure what to do about it? Valentines Day can be the perfect catalyst for moving toward something more. If You Have a Date Have a date for Valentines? Thought that was the difficult part ... until you tried to plan something? Check out these easy (and affordable) date ideas to help make sure your night is all you want it to be. If Youre in a Long-Distance Relationship Being in a long-distance relationship can be hard enough without things like Valentines Day reminding you of the distance between you and your significant other. Learn more about how to make the distance a little easier.

Compare and differentiate Maoism and Stalinism Term Paper

Compare and differentiate Maoism and Stalinism - Term Paper Example The peasants and workers formed the revolutionary classes under this belief. Marxism-Leninism is a globally inclined ideology that was of the belief that the communist revolution was inevitable. It further advocated that once the revolution had happened in one country, then others will soon have their own revolutions. Thus, it was the duty of believers of Marxism-Leninism to try to export the revolution. Both Stalin and Mao tried to implement Marxism-Leninism in their countries albeit with some modifications to suit their present situations and personal convictions. The two leaders implemented â€Å"Five Year Plans† in their countries in order to spur development. Stalin’s First Five Year Plan (FFYP) begun early in 1926. His major focus was to transform the Soviet Union from an agrarian economy to a prominent industrial power. He argued that rapid industrialization was critical for the Soviet Union to flourish and survive as a world power. Stalin’s FFYP was prese nted as a Second Revolution and this helped him to mobilize the peasants as they perceived themselves to be in a class war with their previous oppressors (Keefe, 2009). Rather than follow Marxism-Leninism, the FFYP was a revolution from above; not from the masses. Stalin created a highly centralized command economy under the auspices of the State Planning Committee (Gosplan). The communist tenet of equality was disregarded as Stalin gave incentives to Managers and skilled workers. It should be noted that the FFYP put heavy emphasis on the heavy industry as massive resources were put in place to develop the oil and steel industry. Mao’s began implementing his First Five Year Plan (FFYP) in 1953. According to Friedman (2001), Mao’s core goal was to end Chinese dependency on agriculture and transform the country into an industrialized economy. Mao’s plan was very similar to Stalin’s since it also advocated for rapid industrialization so as to make China a wo rld power. The Chinese relied on the assistance of the Russians both economically and technically. Mao reorganized his administration to reduce bureaucracy and increase the country’s labor force. This move was aimed at reducing the chances of derailing progress due to a long chain of command. The peasants were required to diversify from agriculture to industrial work. Although the effectiveness of the First Five Year Plans for both leaders was questionable, they nevertheless went ahead to launch their Second Five Year Plans (SFYP). Stalin implemented his SFYP beginning 1933. This plan utilized the industries built during the previous plan to increase productivity. The Second Five Year Plan gave more attention to consumer goods unlike its predecessor. In retrospect, this plan was much more realistic and achieved considerably better results. After Mao’s FFYP, he implemented a much more audacious policy in the Second Five Year Plan. Mao believed that China would develop m ore rapidly if all resources were used to develop both industry and the agricultural sector concurrently. He utilized the country’s cheap labor to provide services primarily to the grain and steel industry. However, poor workmanship resulted in the failure of the steel production projects. The steel plants were poorly planned and there was scarcity of qualified engineers to oversee the work (Mark, 2001). In order to reign on the agricultural sector, both Stalin and Mao implemented the policy of Collectivization. Under Stalin,

Computer Methods Math Problem Example | Topics and Well Written Essays - 1000 words

Computer Methods - Math Problem Example S' will be computed by finding T - S, so S' = { (1, 1), (2, 1), (2, 2) } Question 2 1. a) Using the following propositions h: it is humid c: it is cloudy and d: it is raining express the following logical expressions in good English. i) (hc)r ii) (rh)c b) Assuming and S is a set of lectures and the and the predicatesL(x): x is a lecturer and A(x): x is articulate write the following sentences in symbolic form i) Larry is an articulate lecturer. ii) There is a lecturer who is not articulate. iii) Not every lecturer is articulate. What is the relationship between predicates (ii) and (iii) c) Determine the truth table for (pq)(pq) State whether this expression is contingency, a contradiction or a tautology. Solution a) i) (hc)r the atmosphere is humid cloudy and it is not raining ii) (rh)c if atmosphere is raining or humid then atmosphere is cloudy. b) (i) Larry is an articulate lecturer. L(Larry) A(Larry) (ii) There is a lecturer who is not articulate. To solve this we will use the concept of universal quantifiers $(x) Which means that a statement is true for all values of x. Now the statement in symbolic form is: "(x)[L(x) 'A(x)]' Which means that "it is not true that all the lecturers are articulate". So in this sense this predicate describes that "there are some lecturers who are not articulate" (iii) Not every lecturer is articulate. "(x)[L(x) 'A(x)]' The relationship between last two predicates is that these define same thing i.e. "Not every lecturer is articulate" does not ever means that " All the lecturer are not articulate" it could mean...And all the points that are not common in any set are placed in circles where no intersection is occurring. The relationship between last two predicates is that these define same thing i.e. "Not every lecturer is articulate" does not ever means that " All the lecturer are not articulate" it could mean that "There are some lecturers who are not articulate" so we can not use universal quantifiers for this predicate hence it means that "Not every lecture is articulate but there are some that can be articulate" so in this sense of interpretation last two predicates are same.