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4.3.2.No special cooling arrangements are necessary for small transformers, natural cooling being sufficient.

4.3.3.All drills are flame-proof constructions, the motor, the starting switch and the cable entry having separate flame-proof enclosures.

4.3.4.With the experiments having been carried out, we started new investigations.

4.3.5.The forces imposed upon the bridge being determined, it is possible to take into account the bearing capacity of stratum..

4.4. Перепишіть речення, перекладіть речення англійською мовою, вживаючи незалежний дієприкметниковий комплекс

(The Absolute Participle Complex).

4.4.1.День був ясний, ми відкрили вікна.

4.4.2.Коли електрони рухаються по проводу, виробляється електрична енергія.

4.4.3.Розрахунки було обчислено, ми здали контрольну роботу викладачеві..

4.5. Перепишіть речення і перекладіть рідною мовою, звертаючи увагу на об’єктний інфінітивний комплекс

(Complex Object).

4.5.1.We know them to have had an interesting report.

4.5.2.I saw the threading tools put into the box.

4.5.3.I did not see him inspect the engine when I came into the lab.

4.5.4.He likes people to tell truth.

4.5.5.She noticed him closing the bonnet .

4.6.Перепишіть речення і перекладіть рідною мовою, звертаючи увагу на суб’єктний інфінітивний комплекс (Complex Subject).Перекладіть англійською мовою.

4.6.1.The above mentioned reactions were certain to proceed violently.

4.6.2.The goods are unlikely to be unloaded today.

4.6.3.Passenger traffic is expected to continue increasing.

4.6.4.The UNO can be said to have been founded to maintain international peace and security.

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4.6.5. The idea of space flight appears to have been attracting the attention of the people since the remotest times.

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

4.7.1.Я ненавиджу, коли ви розповідаєте про станки.

4.7.2.Вона бажає, щоб ремонт було закінчено як можна швидше.

4.7.3.Чай, здається, без цукру.

4.7.4.Відомо, що довідник продається в цьому магазині.

4.7.5.Можна чекати, що інструмент буде наточено.

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

4.8.1. Електротехнічний факультет

BATTERIES

An electrical battery is a combination of one or more electrochemical cells used to convert stored chemical energy into electrical energy. Since the invention of the first voltaic pile in 1800 by Alessandro Volta, the battery has become a common power source for many household and industrial applications.

A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half cells connected in series by a conductive electrolyte containing anions and cations. One half-cell includes electrolyte and the electrode to which anions (negatively charged ions) migrate, i.e., the anode or negative electrode; the other half-cell includes electrolyte and the electrode to which cations (positively charged ions) migrate, i.e., the cathode or positive electrode. The electrodes do not touch each other but are electrically connected by the electrolyte.

There are two types of batteries: primary batteries (disposable batteries), which are designed to be used once and discarded when they are exhausted, and secondary batteries (rechargeable batteries), which are designed to be recharged and used multiple times.

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Miniature cells are used to power devices such as hearing aids and wristwatches; larger batteries provide standby power for telephone exchanges or computer data centers. Primary batteries can produce current immediately on assembly. Disposable batteries are intended to be used once and discarded. These are most commonly used in portable devices that have low current drain, are only used intermittently, or are used well away from an alternative power source, such as in alarm and communication circuits where other electric power is only intermittently available. Secondary batteries must be charged before use; they are usually assembled with active materials in the discharged state. Rechargeable batteries or secondary cells can be recharged by applying electrical current, which reverses the chemical reactions that occur during its use.

The oldest form of rechargeable battery is the lead-acid battery. This battery is notable in that it contains a liquid in an unsealed container, requiring that the battery be kept upright and the area be well ventilated to ensure safe dispersal of the hydrogen gas produced by these batteries during overcharging. The lead-acid battery is also very heavy for the amount of electrical energy it can supply. Despite this, its low manufacturing cost and its high surge current levels make its use common where a large capacity (over approximately 10Ah) is required or where the weight and ease of handling are not concerns.

Дайте відповіді на запитання.

1.Who invented the first batteries?

2.How many types of batteries are there?

3.What is the oldest type of the secondary batteries?

4.Can you name advantages and disadvantages of lead-acid batteries?

5.How is the battery constructed?

4.8.2. Інженерно-фізичний факультет

DIE CASTING

Die casting is the process of forcing molten metal under high pressure into mold cavities (which are machined into dies). Most die

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castings are made from non-ferrous metals, specifically zinc, copper, aluminium, magnesium, lead, pewter and tin based alloys, although ferrous metal die castings are possible. The die casting method is especially suited for applications where a large quantity of small to medium sized parts are needed, ensuring precise surface quality and dimensional consistency. This level of versatility has placed die castings among the highest volume products made in the metalworking industry. In recent years, injection-molded plastic parts have replaced some die castings because they are cheaper and lighter.[citation needed] Plastic parts are a practical alternative if hardness is not required and little strength is needed.

Die casting equipment was invented in 1838 for the purpose of producing movable type for the printing industry. The first die casting-related patent was granted in 1849 for a small hand operated machine for the purpose of mechanized printing type production. Other applications grew rapidly, with die casting facilitating the growth of consumer goods and appliances by making affordable the production of intricate parts in high volumes.

There are four major steps in the die casting process. First, the mold is sprayed with lubricant and closed. The lubricant both helps control the temperature of the die and it also assists in the removal of the casting. Molten metal is then shot into the die under high pressure; between 10—175 MPa. Once the die is filled the pressure is maintained until the casting has solidified. The die is then opened and the shot (shots are different from castings because there can be multiple cavities in a die, yielding multiple castings per shot) is ejected by the ejector pins. Finally, the scrap, which includes the gate, runners, sprues and flash, must be separated from the casting(s). This is often done using a special trim die in a power press or hydraulic press. An older method is separating by hand or by sawing, which case grinding may be necessary to smooth the scrap marks. A less labor-intensive method is to tumble shots if gates are thin and easily broken; separation of gates from finished parts must follow. This scrap is recycled by remelting it. Approximately 15% of the

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metal used is wasted or lost due to a variety of factors. The highpressure injection leads to a quick fill of the die, which is required so the entire cavity fills before any part of the casting solidifies. In this way, discontinuities are avoided even if the shape requires difficult- to-fill thin sections. This creates the problem of air entrapment, because when the mold is filled quickly there is little time for the air to escape. This problem is minimized by including vents along the parting lines, however, even in a highly refined process there will still be some porosity in the center of the casting.

Дайте відповіді на запитання.

1.What is called die casting?

2.What are the casting steps?

3.Why is the metal wasted or lost?

4.What was the purpose of die casting invention?

5.What is this method suited for?

4.8.3. Машинобудівний факультет

LATHES

A lathe is a machine tool which spins a block of material to perform various operations such as cutting, sanding, knurling, drilling, or deformation with tools that are applied to the workpiece to create an object which has symmetry about an axis of rotation. Lathes are used in woodturning, metalworking, metal spinning, and glassworking. Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces and screw threads or helices. The material can be held in place by either one or two centers, at least one of which can be moved horizontally to accommodate varying material lengths. Other workholding methods include clamping the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps or dogs.

The lathe is an ancient tool, dating at least to the Egyptians and known and used in Assyria, Greece, the Roman and Byzantine Empires. A lathe may or may not have a stand (or legs), which sits on the floor and elevates the lathe bed to a working height. Some lathes are small and sit on a workbench or table, and do not have a

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stand. Almost all lathes have a bed, which is (almost always) a horizontal beam. At one end of the bed (almost always the left, as the operator faces the lathe) is a headstock. The headstock contains highprecision spinning bearings. Rotating within the bearings is a horizontal axle, with an axis parallel to the bed, called the spindle. Spindles are often hollow, and have exterior threads and/or an interior. Spindles are powered, and impart motion to the workpiece.

The spindle is driven, either by foot power from a treadle and flywheel or by a belt or gear drive to a power source. In most modern lathes this power source is an integral electric motor, often either in the headstock, to the left of the headstock, or beneath the headstock, concealed in the stand.

The counterpoint to the headstock is the tailstock, sometimes referred to as the loose head, as it can be positioned at any convenient point on the bed, by undoing a locking nut, sliding it to the required area, and then relocking it. The tailstock contains a barrel which does not rotate, but can slide in and out parallel to the axis of the bed, and directly in line with the headstock spindle. The barrel is hollow, and usually contains a taper to facilitate the gripping of various type of tooling.

Дайте відповіді на запитання.

1.What are the most common parts of the lathe?

2.What kinds of operations can be performed on a lathe?

3.How many spindles are there, do they rotate?

4.What are spindles driven by?

5.What is a barrel?

4.8.4. Транспортний факультет

SHIP TRANSPORT

Ship transport is watercraft carrying people (passengers) or goods (cargo). Sea transport has been the largest carrier of freight throughout recorded history. Although the importance of sea travel for passengers has decreased due to aviation, it is effective for short trips and pleasure cruises. Ship transport can be over any distance by boat, ship, sailboat or barge, over oceans and lakes, through canals or

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along rivers. Shipping may be for commerce, recreation or the military. Virtually any material that can be moved, can be moved by water.

Ships and other watercraft are used for ship transport. Various types can be distinguished by propulsion, size or cargo type. Recreational or educational craft still use wind power, while some smaller craft use internal combustion engines to drive one or more propellers, or in the case of jet boats, an inboard water jet.

Most modern merchant ships can be placed in one of a few categories, such as:

-bulk carriers are cargo ships used to transport bulk cargo items such as ore or food staples (rice, grain, etc.) and similar cargo.

-container ships are cargo ships that carry their entire load in trucksize containers, in a technique called containerization. They form a common means of commercial intermodal freight transport. Informally known as "box boats," they carry the majority of the world's dry cargo.

-tankers are cargo ships for the transport of fluids, such as crude oil, petroleum products, liquefied petroleum gas, liquefied natural gas and chemicals, also vegetable oils, wine and other food - the tanker sector comprises one third of the world tonnage.

-reefer ships are cargo ships typically used to transport perishable commodities which require temperature-controlled transportation, mostly fruits, meat, fish, vegetables, dairy products and other foodstuffs.

-roll-on/roll-off ships are cargo ships designed to carry wheeled cargo such as automobiles, trailers or railway carriages.

-ferries are a form of transport, usually a boat or ship, but also other forms, carrying (or ferrying) passengers and sometimes their vehicles. Ferries are also used to transport freight (in lorries and sometimes unpowered freight containers) and even railroad cars.

-cruise ships are passenger ships used for pleasure voyages, where the voyage itself and the ship's amenities are considered an essential part of the experience.

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-a tugboat is a boat used to manoeuvre, primarily by towing or pushing other vessels (see shipping) in harbours, over the open sea or through rivers and canals. They are also used to tow barges, disabled ships, or other equipment like towboats.

-a barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Most barges are not self-propelled and need to be moved by tugboats towing or towboats pushing them.

Дайте відповіді на запитання.

1.What does ship transport carry?

2.What is used to ship people and goods?

3.Which types of ships can you mention?

4.What are merchant ships?

5.What is used to tow barges?

4.8.5. Факультет інформаціонно-обчислювальної техніки

COMPUTER NETWORKS

A computer network, often simply referred to as a network, is a collection of computers and devices connected by communications channels that facilitates communications among users and allows users to share resources with other users. Networks may be classified according to a wide variety of characteristics. This article provides a general overview of types and categories and also presents the basic components of a network.

Computer networks can be used for several purposes:

-facilitating communications. Using a network, people can communicate efficiently and easily via e-mail, instant messaging, chat rooms, telephony, video telephone calls, and videoconferencing.

-sharing hardware. In a networked environment, each computer on a network can access and use hardware on the network. Suppose several personal computers on a network each require the use of a laser printer. If the personal computers and a laser printer are connected to a network, each user can then access the laser printer on the network, as they need it.

-sharing files, data, and information. In a network environment, any authorized user can access data and information stored on other

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computers on the network. The capability of providing access to data and information on shared storage devices is an important feature of many networks.

- sharing software. Users connected to a network can access application programs on the network.

Computer networks can be classified according to the hardware and software technology that is used to interconnect the individual devices in the network, such as optical fiber, Ethernet, Wireless LAN, HomePNA, Power line communication or G.hn. Networks are often classified as local area network (LAN), wide area network (WAN), metropolitan area network (MAN), personal area network (PAN), virtual private network (VPN), campus area network (CAN), storage area network (SAN), and others, depending on their scale, scope and purpose. (e.g., Controller Area Network (CAN)) Usage, trust level, and access right often differ between these types of networks.

Computer networks may be classified according to the network topology upon which the network is based, such as bus network, star network, ring network, mesh network, star-bus network, tree or hierarchical topology network. Network topology is the coordination by which devices in the network are arranged in their logical relations to one another, independent of physical arrangement. Even if networked computers are physically placed in a linear arrangement and are connected to a hub, the network has a star topology, rather than a bus topology. In this regard the visual and operational characteristics of a network are distinct. Networks may be classified based on the method of data used to convey the data, these include digital and analog networks.

Дайте відповіді на запитання.

1.What is a computer network?

2.How many purposes does a network serve?

3.How are the networks classified?

4.What do you know about network topology?

5.Which topology is the most widely applied?

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4.8.6. Факультет радіо приладобудування

BIPOLAR TRANSISTORS

A bipolar (junction) transistor (BJT) is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons and holes. Early transistors were made from germanium but most modern BJTs are made from silicon.

Charge flow in a BJT is due to bidirectional diffusion of charge carriers across a junction between two regions of different charge concentrations. This mode of operation is contrasted with unipolar transistors, such as field-effect transistors, in which only one carrier type is involved in charge flow due to drift. By design, most of the BJT collector current is due to the flow of charges injected from a high-concentration emitter into the base where they are minority carriers that diffuse toward the collector, and so BJTs are classified as minority-carrier devices.

A BJT consists of three differently doped semiconductor regions, the emitter region, the base region and the collector region. These regions are, respectively, p type, n type and p type in a PNP, and n type, p type and n type in a NPN transistor. Each semiconductor region is connected to a terminal, appropriately labeled: emitter, base and collector.

The base is physically located between the emitter and the collector and is made from lightly doped, high resistivity material. The collector surrounds the emitter region, making it almost impossible for the electrons injected into the base region to escape being collected, thus making the resulting value of α very close to unity, and so, giving the transistor a large β. A cross section view of a BJT indicates that the collector–base junction has a much larger area than the emitter–base junction.

The bipolar junction transistor, unlike other transistors, is usually not a symmetrical device. This means that interchanging the collector and the emitter makes the transistor leave the forward

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