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3.7. Перекладіть англійською, вживаючи об’єктний інфінітивний комплекс (Complex Object) та суб’єктний інфінітивний комплекс (Complex Subject).

3.7.1.Говорять, він зараз в цеху.

3.7.2.Здається, ваша відповідь задовольнила начальника.

3.7.3.Ніхто не помітив, як вони вийшли з класу.

3.7.4.Я не вважаю його гідним працівником.

3.7.5.Я чекаю, що мене запросять на зустріч.

3.8.Перепишіть текст за фахом та перекладіть його рідною мовою.

3.8.1.Електротехнічний факультет

TRANSFORMERS

A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core, and thus a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF) or "voltage" in the secondary winding. This effect is called mutual induction.

If a load is connected to the secondary, an electric current will flow in the secondary winding and electrical energy will be transferred from the primary circuit through the transformer to the load. In an ideal transformer, the induced voltage in the secondary winding is in proportion to the primary voltage, and is given by the ratio of the number of turns in the secondary to the number of turns in the primary.

In the vast majority of transformers, the windings are coils wound around a ferromagnetic core, air-core transformers being a notable exception.

Transformers range in size from a thumbnail-sized coupling transformer hidden inside a stage microphone to huge units weighing hundreds of tons used to interconnect portions of power grids. All operate with the same basic principles, although the range of designs

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is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in nearly all electronic devices designed for household ("mains") voltage.

The ideal transformer model assumes that all flux generated by the primary winding links all the turns of every winding, including itself. In practice, some flux traverses paths that take it outside the windings. Leakage results in energy being alternately stored in and discharged from the magnetic fields with each cycle of the power supply. It is not directly a power loss, but results in inferior voltage regulation, causing the secondary voltage to fail to be directly proportional to the primary, particularly under heavy load. However, in some applications, leakage can be a desirable property, and long magnetic paths, air gaps, or magnetic bypass shunts may be deliberately introduced to a transformer's design to limit the shortcircuit current it will supply. Air gaps are also used to keep a transformer from saturating, especially audio-frequency transformers in circuits that have a direct current flowing through the windings.

Дайте відповіді на запитання.

1.What is mutual induction?

2.How do transformers range in size?

3.Why does a leakage result?

4.Where are the transformers applied?

5.Where can leakage be a desirable property?

3.8.2.Інженерно-фізичний факультет

MOULDING SAND

The sand used for making moulds for steel castings differs greatly from that used in other branches of moulding. It must be more refractory and open grained, because the metal is poured at an extremely high temperature and solidifies very rapidly. If the sand is not refractory enough, it will fuse with the metal. The sand being not open grained, the gases will not escape from the mould rapidly enough, and blowholes will be formed in the casting. Many steel casting are obtained with green sand moulds. Green sand is an

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aggregate of sand, bentonite clay, pulverized coal and water. The largest portion of the aggregate is always sand, which can be either silica or olivine. There are many recipes for the proportion of clay, but they all strike different balances between mouldability, surface finish, and ability of the hot molten metal to degas. Sand casting is one of the earliest forms of casting practiced due to the simplicity of materials involved. It still remains one of the cheapest ways to cast metals because of that same simplicity. Other methods of casting, such as those using shell moulds boast higher quality of surface finish, but higher cost.

Green sand (and other casting sands) is usually housed in what casters refer to as flasks which are nothing other than boxes without a bottom or lid. The box is split into two halves which are stacked together in use. The halves are referred to as the top (cope) and bottom (drag) flask respectively. Green sand is not green in color, but "green" in the sense that it is used in a wet state (akin to green wood). An alternative casting method is to heat-dry the moulded sand before pouring the molten metal. This dry sand casting process results in a more rigid mold better suited to heavier castings. Sand moulds are made by shaping the moulding sand around a pattern, which is to have the same shape as the finished object, but their size should be a little larger as the steel casting shrinks while cooling. Moulding sand is to be mixed with water in a certain proportion. Many of the smaller steel castings are used as they come from the moulds, but most of the larger ones have to be annealed to relieve the cooling strains formed when the metal solidifies. Cast steel parts enter into the make-up of railroad equipment, agricultural machinery, and many other products where great strength is required. The tensile strength of steel castings is from 55,000 to 70,000 lbs. per square inch. Alloy steel castings are coming into more general use with each year, and they are influencing the manufacturing methods. It has been found possible to cast with this alloy some shapes that formerly were necessary made in other ways. Much research is being done to improve not only its strength, but also its wearing qualities.

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Now castings with higher tensile strength are produced, the strength depending upon the composition of the alloy and the methods of het treatment.

Дайте відповіді на запитання.

1.What sand is used for making steel castings?

2.Why must the pattern be a little larger than the castings?

3.Where is the green sand usually housed?

4.What are the composites if the green sand?

5.What does the tensile strength depend on?

3.8.3. Машинобудівний факультет

SHAPERS

A shaper is a type of machine tool that uses linear relative motion between the workpiece and a single-point cutting tool to machine a linear toolpath. A shaper is analogous to a planer, but smaller, and with the cutter riding a ram that moves above a stationary workpiece, rather than the entire workpiece moving beneath the cutter. The ram is moved back and forth typically by a crank inside the column; hydraulically actuated shapers also exist. Shapers are mainly classified as standard, draw-cut, horizontal, universal, vertical, geared, crank, hydraulic, contour and traveling head. The horizontal arrangement is the most common. Vertical shapers are generally fitted with a rotary table to enable curved surfaces to be machined. The vertical shaper is essentially the same thing as a slotter (slotting machine), although technically a distinction can be made if one defines a true vertical shaper as a machine whose slide can be moved from the vertical. A slotter is fixed in the vertical plane.

Very small machines have been successfully made to operate by hand power. As size increases, the mass of the machine and its the power requirements increase, and it becomes necessary to use a motor or other supply of mechanical power. A shaper operates by moving a hardened cutting tool backwards and forwards across the workpiece. On the return stroke of the ram the tool is lifted clear of the workpiece, reducing the cutting action to one direction only.

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The workpiece mounts on a rigid, box-shaped table in front of the machine. The height of the table can be adjusted to suit this workpiece, and the table can traverse sideways underneath the reciprocating tool, which is mounted on the ram. Table motion may be controlled manually, but is usually advanced by an automatic feed mechanism acting on the feedscrew. The ram slides back and forth above the work. At the front end of the ram is a vertical tool slide that may be adjusted to either side of the vertical plane along the stroke axis. This tool-slide holds the clapper box and toolpost, from which the tool can be positioned to cut a straight, flat surface on the top of the workpiece. The tool-slide permits feeding the tool downwards to deepen a cut. This adjustability, coupled with the use of specialized cutters and toolholders, enable the operator to cut internal and external gear tooth profiles, splines, dovetails, and keyways.

Дайте відповіді на запитання.

1.What is a shaper?

2.Is there any difference between shapers and slotters?

3.What does the mode of operation (hand or mechanical) depend on?

4.How does a shaper operate?

5.Why does the tool-slide permit feeding the tool downwards?

3.8.4.Транспортний факультет

TGV

A TGV (meaning high-speed train) is France's high-speed rail service, currently operated by SNCF Voyages, the long-distance rail branch of SNCF, the French national rail operator. It was developed during the 1970s by Alstom and SNCF. Although originally designed to be powered by gas turbines, the TGV prototypes evolved into electric trains. Following the inaugural TGV service between Paris and Lyon in 1981, the TGV network, centered on Paris, has expanded to connect cities across France and in adjacent countries.

The success of the first line led to an expansion of the network, with new lines built in the south, west, north and east of the

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country. Eager to emulate the success of the French network, neighbouring countries such built their own high-speed lines. TGVs link with Switzerland through the French network, with Belgium, Germany and the Netherlands through the Thalys network, and the Eurostar network links France and Belgium with the United Kingdom. Several lines are planned, including extensions within France and to surrounding countries.

LGV construction is the process by which the land on which TGV trains are to run is prepared for their use, involving carving the trackbed and laying the track. LGV construction is similar to that of normal railway lines, but with a few key differences. The radii of curves are larger so that trains can traverse them at higher speeds without increasing the centripetal acceleration felt by passengers. Lines used only for high-speed traffic can incorporate steeper gradients than normal. This facilitates the planning of LGVs and reduces their cost of construction. The high power/weight and adhesive weight/total weight ratios of TGVs allow them to climb much steeper grades than conventional trains. The considerable momentum at high speeds also helps to climb these slopes very fast without greatly increasing their energy consumption.

Track alignment is more precise than on normal railway lines, and ballast is in a deeper-than-normal profile, resulting in increased load-bearing capacity and track stability. LGV track is anchored by more sleepers or ties per kilometre than normal, and all are made of concrete. Use of continuously welded rails in place of shorter, jointed rails yields a comfortable ride at high speed, without the "clicketyclack" vibrations induced by rail joints.

The points or switches on LGVs are different from those on the lignes classiques. Every LGV set of points incorporates a swingnose crossing which eliminates the gap in rail support as wheels of a train pass over the 'frog' of conventional points, causing shock and vibration. Eliminating shock and vibration makes the passage of a TGV over an LGV switch imperceptible to passengers,

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and reduces stresses on wheels and track. In addition, LGV switches permit much higher speeds.

The diameter of tunnels is greater than normally required by the size of the trains, especially at entrances. This limits the effects of air pressure changes, which could be problematic at TGV speeds.

Дайте відповіді на запитання.

1.What is a TGV?

2.When and where was it first introduced?

3.Where did the success lead?

4.How does a LGV construction differ from the ordinary railway lines?

5.What is the track made of?

3.8.5.Факультет інформаціонно-обчислювальної техніки

PROGRAMMING LANGUAGES

A programming language is an artificial language designed to express computations that can be performed by a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine, to express algorithms precisely, or as a mode of human communication.

Many programming languages have some form of written specification of their syntax (form) and semantics (meaning). Some languages are defined by a specification document. For example, the C programming language is specified by an ISO Standard. Other languages, such as Perl, have a dominant implementation that is used as a reference.

Many languages have been designed from scratch, altered to meet new needs, combined with other languages, and eventually fallen into disuse. Although there have been attempts to design one "universal" programming language that serves all purposes, all of them have failed to be generally accepted as filling this role. The need for diverse programming languages arises from the diversity of contexts in which languages are used:

- programs range from tiny scripts written by individual hobbyists to huge systems written by hundreds of programmers;

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-programmers range in expertise from novices who need simplicity above all else, to experts who may be comfortable with considerable complexity;

-programs must balance speed, size, and simplicity on systems ranging from microcontrollers to supercomputers;

-programs may be written once and not change for generations, or they may undergo continual modification;

-programmers may simply differ in their tastes: they may be accustomed to discussing problems and expressing them in a particular language.

One common trend in the development of programming languages has been to add more ability to solve problems using a higher level of abstraction. The earliest programming languages were tied very closely to the underlying hardware of the computer. As new programming languages have developed, features have been added that let programmers express ideas that are more remote from simple translation into underlying hardware instructions. Because programmers are less tied to the complexity of the computer, their programs can do more computing with less effort from the programmer. This lets them write more functionality per time unit.

Дайте відповіді на запитання.

1.Why is a computer language designed?

2.What is a language specification?

3.What does the need for diverse languages arise from?

4.Why are new features added to the existing languages?

5.What mostly used languages can you name?

3.8.6. Факультет радіо приладобудування

COMPUTER SECURITY

Computer security is a branch of computer technology known as information security as applied to computers and networks. The objective of computer security includes protection of information and property from theft, corruption, or natural disaster, while allowing the information and property to remain accessible and productive to its intended users. The term computer system security means the

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collective processes and mechanisms by which sensitive and valuable information and services are protected from publication, tampering or collapse by unauthorized activities or untrustworthy individuals and unplanned events respectively. The strategies and methodologies of computer security often differ from most other computer technologies because of its somewhat elusive objective of preventing unwanted computer behavior instead of enabling wanted computer behavior.

The technologies of computer security are based on logic. As security is not necessarily the primary goal of most computer applications, designing a program with security in mind often imposes restrictions on that program's behavior.

There are 4 approaches to security in computing, sometimes a combination of approaches is valid:

-trust all the software to abide by a security policy but the software is not trustworthy (this is computer insecurity);

-trust all the software to abide by a security policy and the software is validated as trustworthy (by tedious branch and path analysis for example);

-trust no software but enforce a security policy with mechanisms that are not trustworthy (again this is computer insecurity);

-trust no software but enforce a security policy with trustworthy hardware mechanisms.

There are various strategies and techniques used to design security systems. However there are few, if any, effective strategies to enhance security after design. One technique enforces the principle of least privilege to great extent, where an entity has only the privileges that are needed for its function. That way even if an attacker gains access to one part of the system, fine-grained security ensures that it is just as difficult for them to access the rest.

Дайте відповіді на запитання.

1.What is the purpose of the computer security?

2.What does the term security means concerning computers?

3.What are the strategies based on?

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4.Сan you describe the 4 approaches of the security?

5.Is there one single effective computer security strategy? Why?

Варіант №4

4.1.Перепишіть речення та перекладіть рідною мовою. Визначте тип умовного речення.

4.1.1.If Germanium had not been properly purified, it would not have suited for transistors.

4.1.2.They will be able to charge an object by induction unless they bring a charged body near it.

4.1.3.If the contact opens and closes very quickly, the amount of arcing will be greatly reduced.

4.1.4.If the whole expansion were performed in one cylinder this cylinder would have sufficient strength to withstand the high initial steam pressure.

4.1.5.If the members of the expedition used the camera for underwater photography, they might obtain valuable data.

4.2.Поставте дієслово у дужках в потрібному часі, зважаючи на тип умовного речення. Перекладіть речення рідною мовою.

4.2.1.If the ice in the Atlantic (to be) to be melted, it would raise ocean level by 50 meters.

4.2.2.Had I had this information before, I (to act) differently.

4.2.3.Unless you can deliver the machines by the 15th of July, we (to be compelled) to cancel the order.

4.2.4.I the weather (to be) so hot last month, the goods would not have gone bad during transportation.

4.2.5.Were he here, I (to know) it at once.

4.3.Перепишіть речення і перекладіть рідною мовою, звертаючи увагу на незалежний дієприкметниковий комплекс (The Absolute Participle Complex).

4.3.1.Alloying elements for making steel are nickel, chromium,

manganese, nickel increasing strength and hardness of the steel..

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