Английский язык. Учебное пособие по развитию навыков устной речи и чтения для магистрантов технических специальностей
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Text 4 PROCESSED MEAT PRODUCTS 1. Read the text below and put in the proper word from the vocabulary: pork, pasteurizing, meat, water-holding, maturation, depend on, smoked, value. The commonest cured products are sausages, bacon, pork shoulder, ham, luncheon meat. Any type of … can be cured either as whole cuts or after comminution. Bacon is cured …, in various countries traditionally made from specified parts of the pig but it can be made from any part. There are modifications of the process including so called sweet cure with added sugar (0.25%) and mild cure with less salt. Ham is the cured product of the upper leg and buttock of the pig and differs from gammon only in that the latter is cut from the side of bacon after it has been cured. It is stable when raw after a certain period of … but is often cooked to pasteurisation temperature, 70°C, or it may be canned at … temperature. It may be … as an additional means of preservation and flavouring. Comminuted products such as sausages and luncheon meats are based on lean meat, which, technologically, provides water-holding and meat-binding capacity, with the addition of fatty meats and, sometimes, organ meats. The amount of these is limited otherwise the products have an unattractive soft texture and high shrinkage on cooking. The ingredients include cereals and potato starch, termed fillers, which also serve to bulk out the supply of meat products («meat extenders»). Other ingredients include a number of substances which have considerable … and binding capacity («binders»). These include egg or egg yolk blood plasma, skim milk powder, caseinates, soya isolates, wheat gluten, whey protein and dehydrated products derived from various vegetable proteins (soybean, safflower, corn, peanut and pea protein) and their binding properties … their ability to form irreversible gels on mild heating which serve to hold together the small pieces of meat. It is not posssible to generalise about the nutritional … of products of such variable composition. Text 5 THE DANGERS OF COW'S MILK 1. Read the text and put the paragraphs (A-D) into the correct order (1-4). Humans place themselves in the odd position of being the only animals that consume milk after weaning. A The harmful components of cow's milk include all the major parts of it, as well as some more minor elements. Lactose is a sugar meant for babies, but it's generally harmful to adults. The proteins in cow's milk are different from human milk proteins and cause problems of digestion, intolerance, impaired absorption of other nutrients, and autoimmune reactions. Few of the proteins meant for baby cows are found naturally in human mother's milk, and none are found in any natural adult human food. Even the high protein content in cow’s milk creates problems. Human babies need the saturated fats and cholesterol in mother's milk. Bovine milk fat is not appropriately composed for human babies and is only deleterious to the health of children and adults. Cow hormones are not meant for humans, and older children and adults are not meant to consume hormones. And, cows have been selectively bred over time to create high levels of these hormones – those being the cows that grow the fastest and produce the greatest amount of milk. Cows also concentrate pesticides and pollutants into their milk fat, from their high dietary food and water requirements. The high amount of drugs now given to cows adds to this chemical soup. But we need milk to build strong bones, don't we? Actually, heavy milk consumption leads to increased osteoporosis. B Today, many of the problems parents have with their babies are linked to new parenting and feeding techniques that have been implemented during the recent century. Colic, for instance, is far more common in the U.S. than in many other places around the world. Two chief causes for its rise are the stress suffered by babies being regularly separated from their mothers, and the common difficulties babies have tolerating the large cow's milk proteins in infant formulas and breastfeeding mothers' diets. Cow's milk is a foreign substance that has pervaded every corner of our diets – starting with artificial infant feeds, but finding its way into mother's breastmilk through the foods she eats as well. As it turns out, health problems such as childhood diabetes, obesity, bowel disease, osteoporosis, heart disease, cataracts, colic, ear infections, hyperactivity, and cancer, on the rise in both children and adults, are strongly linked to infant feeding choices. C Knowing and avoiding the potentially harmful effects that high dairy consumption and milk-sensitivity reactions can have on your child is just as important and loving as nursing, close bonding, and informed health care decisions. What we feed our children matters; how we parent them matters. These measures will lead to the best health, comfort and happiness available to a child. Parents have the power to create and enjoy healthier, happier children with brighter futures. D While there are literally thousands of research studies, each revealing at least one of milk's hazards, the dairy industry goes to great lengths to stifle any damaging rumors. Blanket statements, such as, «There is simply no scientific research to back up these claims,» are easily made. With a long and successful history of dairy promotion, these are readily accepted by the public. More people need to go to the real research and learn the truth for themselves. They should be very suspicious of these foreign foods being pushed on their children. They should question motives as well as possible outcomes. Although some of the dangers of cow's milk consumption relate more to adults than to children, parents' actions form the basis for lifelong dairy-consuming habits in their children. Text 6. ROBOTS. HISTORY OF INVENTION 1. Read the text carefully and answer the question. 1) What is the origin of the word «robot»? When and by whom was it first used? 2) What tasks were robots primarily designed for? How can they perform these tasks? 3) How many and what steps were there in robot development? 4) Who developed a truly flexible multipurpose manipulator known as PUMA? What is its basic concept? Robot is a computer-controlled machine that is programmed to move, manipulate objects, and accomplish work while interacting with its environment. Robots are able to perform repetitive tasks more quickly, cheaply, and accurately than humans. The term robot originates from the Czech word robota, meaning «compulsory labor». It was first used in the 1921 play R.U.R. (Rossum's Universal Robots) by the Czech novelist and playwright Karel Capek. The word robot has been used since to refer to a machine that performs work to assist people or work that humans find difficult or undesirable. The concept of automated machines dates to antiquity with myths of mechanical beings brought to life. Automata, or manlike machines, also appeared in the clockwork figures of medieval churches, and 18th-century watchmakers were famous for their clever mechanical creatures. Feedback (self-correcting) control mechanisms were used in some of the earliest robots and are still in use today. An example of feedback control is a watering trough that uses a float to sense the water level. When the water falls past a certain level, the float drops, opens a valve, and releases more water into the trough. As the water rises, so does the float. When the float reaches a certain height, the valve is closed and the water is shut off. The first true feedback controller was the Watt governor, invented in 1788 by the Scottish engineer James Watt. This device featured two metal balls connected to the drive shaft of a steam engine and also coupled to a valve that regulated the flow of steam. As the engine speed increased, the balls swung out due to centrifugal force, closing the valve. The flow of steam to the engine was decreased, thus regulating the speed. Feedback control, the development of specialized tools, and the division of work into smaller tasks that could be performed by either workers or machines were essential ingredients in the automation of factories in the 18th century. As technology improved, specialized machines were developed for tasks such as placing caps on bottles or pouring liquid rubber into tire molds. These machines, however, had none of the versatility of the human arm; they could not reach for objects and place them in a desired location. The development of the multijointed artificial arm, or manipulator, led to the modern robot. A primitive arm that could be programmed to perform specific tasks was developed by the American inventor George Devol, Jr., in 1954. In 1975 the American mechanical engineer Victor Scheinman, while a graduate student at Stanford University in California, developed a truly flexible multipurpose manipulator known as the Programmable Universal Manipulation Arm (PUMA). PUMA was capable of moving an object and placing it with any orientation in a desired location within its reach. The basic multijointed concept of the PUMA is the template for most contemporary robots. Text 7 APPLICATION OF ROBOTS 1. Read the text carefully and answer these question. 1) How do robots work? 2) How many categories can the application of robots be divided into? What are they? 3) What are practical achievements in the field of automated machines? 4) What problems do remain in robot development? How could they be solved? The inspiration for the design of a robot manipulator is the human arm, but with some differences. For example, a robot arm can extend by telescoping – that is, by sliding cylindrical sections one over another to lengthen the arm. Robot arms also can be constructed so that they bend like an elephant trunk. Grippers, or end effectors, are designed to mimic the function and structure of the human hand. Many robots are equipped with special purpose grippers to grasp particular devices such as a rack of test tubes or an arc-welder. The joints of a robotic arm are usually driven by electric motors. In most robots, the gripper is moved from one position to another, changing its orientation. A computer calculates the joint angles needed to move the gripper to the desired position in a process known as inverse kinematics. Some multijointed arms are equipped with servo, or feedback, controllers that receive input from a computer. Each joint in the arm has a device to measure its angle and send that value to the controller. If the actual angle of the arm does not equal the computed angle for the desired position, the servo controller moves the joint until the arm's angle matches the computed angle. Controllers and associated computers also must process sensor information collected from cameras that locate objects to be grasped, or they must touch sensors on grippers that regulate the grasping force. Any robot designed to move in an unstructured or unknown environment will require multiple sensors and controls, such as ultrasonic or infrared sensors, to avoid obstacles. Robots, such as the National Aeronautics and Space Administration (NASA) planetary rovers, require a multitude of sensors and powerful onboard computers to process the complex information that allows them mobility. This is particularly true for robots designed to work in close proximity with human beings, such as robots that assist persons with disabilities and robots that deliver meals in a hospital. Safety must be integral to the design of human service robots. Today most robots are used in manufacturing operations; the applications can be divided into three categories: (1) material handling, (2) processing operations, and (3) assembly and inspection. Material-handling applications include material transfer and machine loading and unloading. Material-transfer applications require the robot to move materials or work parts from one location to another. Many of these tasks are relatively simple, requiring robots to pick up parts from one conveyor and place them on another. Other transfer operations are more complex, such as placing parts onto pallets in an arrangement that must be calculated by the robot. Machine loading and unloading operations utilize a robot to load and unload parts at a production machine. This requires the robot to be equipped with a gripper that can grasp parts. Usually the gripper must be designed specifically for the particular part geometry. In robotic processing operations, the robot manipulates a tool to perform a process on the work part. Examples of such applications include spot welding, continuous arc welding, and spray painting. Spot welding of automobile bodies is one of the most common applications of industrial robots in the United States. The robot positions a spot welder against the automobile panels and frames to complete the assembly of the basic car body. Arc welding is a continuous process in which the robot moves the welding rod along the seam to be welded. Spray painting involves the manipulation of a spray-painting gun over the surface of the object to be coated. Other operations in this category include grinding, polishing, and routing, in which a rotating spindle serves as the robot's tool. The third application area of industrial robots is assembly and inspection. The use of robots in assembly is expected to increase because of the high cost of manual labour common in these operations. Since robots are programmable, one strategy in assembly work is to produce multiple product styles in batches, reprogramming the robots between batches. An alternative strategy is to produce a mixture of different product styles in the same assembly cell, requiring each robot in the cell to identify the product style as it arrives and then execute the appropriate task for that unit. The design of the product is an important aspect of robotic assembly. Assembly methods that are satisfactory for humans are not necessarily suitable for robots. Using a screw and nut as a fastening method, for example, is easily performed in manual assembly, but the same operation is extremely difficult for a one-armed robot. Designs in which the components are to be added from the same direction using snap fits and other one-step fastening procedures enable the work to be accomplished much more easily by automated and robotic assembly methods. Inspection is another area of factory operations in which the utilization of robots is growing. In a typical inspection job, the robot positions a sensor with respect to the work part and determines whether the part is consistent with the quality specifications. In nearly all industrial robotic applications, the robot provides a substitute for human labour. There are certain characteristics of industrial jobs performed by humans that identify the work as a potential application for robots: (1) the operation is repetitive, involving the same basic work motions every cycle; (2) the operation is hazardous or uncomfortable for the human worker (e.g., spray painting, spot welding, arc welding, and certain machine loading and unloading tasks); (3) the task requires a work part or tool that is heavy and awkward to handle; and (4) the operation allows the robot to be used on two or three shifts. Many robot applications are for tasks that are either dangerous or unpleasant for human beings. In medical laboratories, robots handle potentially hazardous materials, such as blood or urine samples. Robots are being used to assist surgeons in installing artificial hips, and very high-precision robots can assist surgeons with delicate operations on the human eye. Research in telesurgery uses robots, under the remote control of expert surgeons that may one day perform operations in distant battlefields. In other cases, robots are used in repetitive, monotonous tasks in which human performance might degrade over time. Robots can perform these repetitive, high-precision operations 24 hours a day without fatigue. A major user of robots is the automobile industry. General Motors Corporation uses approximately 16,000 robots for tasks such as spot welding, painting, machine loading, parts transfer, and assembly. Assembly is one of the fastest growing industrial applications of robotics. It requires higher precision than welding or painting and depends on low-cost sensor systems and powerful inexpensive computers. Robots are used in electronic assembly where they mount microchips on circuit boards. Activities in environments that pose great danger to humans, such as locating sunken ships, cleanup of nuclear waste, prospecting for underwater mineral deposits, and active volcano exploration, are ideally suited to robots. Similarly, robots can explore distant planets. NASA's Galileo, an unpiloted space probe, traveled to Jupiter in 1996 and performed tasks such as determining the chemical content of the Jovian atmosphere. Robotic manipulators create manufactured products that are of higher quality and lower cost. But robots can cause the loss of unskilled jobs, particularly on assembly lines in factories. New jobs are created in software and sensor development, in robot installation and maintenance, and in the conversion of old factories and the design of new ones. These new jobs, however, require higher levels of skill and training. Technologically oriented societies must face the task of retraining workers who lose jobs to automation, providing them with new skills so that they can be employable in the industries of the 21st century. Automated machines will increasingly assist humans in the manufacture of new products, the maintenance of the world's infrastructure, and the care of homes and businesses. Robots will be able to make new highways, construct steel frameworks of buildings, clean underground pipelines, and mow lawns. Prototypes of systems to perform all of these tasks already exist. One important trend is the development of microelectromechanical systems, ranging in size from centimeters to millimeters. These tiny robots may be used to move through blood vessels to deliver medicine or clean arterial blockages. They also may work inside large machines to diagnose impending mechanical problems. Perhaps the most dramatic changes in future robots will arise from their increasing ability to reason. The field of artificial intelligence is moving rapidly from university laboratories to practical application in industry, and machines are being developed that can perform cognitive tasks, such as strategic planning and learning from experience. Increasingly, diagnosis of failures in aircraft or satellites, the management of a battlefield, or the control of a large factory will be performed by intelligent computers. |