填空题Nikola Tesla invented alternating current technology that enabled electricity to be transmitted over long distances.___

考题 The long－term assets are known as ______ assets. A fixed ;B current ;C net

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考题 Why is there no natural reason for famine?A、We now have technology to preserve and keep food.B、We can transport food over long distances.C、The government can import food and distribute it to its people.D、Nature can never create any disasters for human beings.

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考题 Liabilities that will be due within a short time (usually one year or less) and that are to be paid out of current assets are called ______.A．long-term trustB．long-term liabilitiesC．current liabilitiesD．current investment

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考题 Which of the following components are used to convert alternating current produced in the generator windings to direct current?A.Armature and equalizerB.Commutator and brushesC.Rotor and interpolesD.Field and exciter

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考题 Dense Wavelength Division Multiplexing (DWDM) is an important innovation in optical networks.Which two descriptions best define DWDM?() A. optical technology for transmitting up to 32 channels over multiple fiber strandsB. optical technology for transmitting up to 16 channels over multiple fiber strandsC. a WDM system that is compatible with EDFA technologyD. a technology for transmitting more closely packed optical signals using more sophisticated transceiver designs than CWDM .

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考题共用题干第二篇Superconducting Ceramic（陶瓷）An underaround revolution beqins this winter. With the flip（轻击）of a switch, 30,000 homes in one part of Detroit will soon become the first in the country to receive electricity transmitted by ice-cold high-performance cables.Other American cities are expected to follow Detroit's example in the years ahead,which could conserve enormousamounts of rower.The new electrical cables at the Frisbie power station in Detroit are revolutionary because they are made of superconductors.A superconductor is a material that transmits electricity with little or no resistance.Resistance is the degree to which a substance resists electric current.All common electrical conductors have a certain amount of electrical resistance.They convert at least some of the electrical energy passing through them into waste heat.Superconductors don't.No one understands how superconductivity works.It just does.Making superconductors isn't easy.A superconducting material has to be cooled to an extremely low temperature to lose its resistance.The first superconductors,made more than 50 years ago,had to be cooled to -263 degrees Celsius before they lost their resistance.Newer superconducting materials lose their resistance at-143 degrees Celsius.The superconductors cable installed at the Frisbie station is made of a ceramic material that contains copper,oxygen,bismuth（秘）,strontium（锶）and calcium (钙）.A ceramic is a hard,strong compound made from clay or minerals.The superconducting ceramic has been fashioned into a tape that is wrapped lengthwise around a long tube filled with liquid nitrogen.Liquid nitrogen is supercold and lowers the temperature of the ceramic tape to the point where it conveys electricity with zero resistance.The United States loses an enormous amount of electricity each year to resistance. Because cooled superconductors have no resistance,they waste much less power. Other cities are watching the Frisbie experiment in the hope that they might switch to superconducting cable and conserve power,too.What is the benefit of the revolution mentioned in the first paragraph?A:With a flip of switch,electricity can be transmitted,B:Other American cities can benefit from the high-performance cables.C:Great amounts of power can be conserved.D:Detroit will first receive electricity transmitted by the new electrical cables.

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考题 How are we to develop new technology if we can’t study current technology to figure out how to______it? A.improve B.rest C.cause D.conceal

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考题 Measles(麻疹)（）a long time to get over.AspendBspendsCtakeDtakes

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考题 Ensuring that data is transmitted securely over an IP network is the main purpose of：（）A、TelnetB、FTPC、SIPD、TLS

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考题过流（Over Current）故障

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考题 You are the network consultant from passguide.com. You have been asked for which two features of optical networks allow data to be transmitted over extremely long distances? （）A、EncryptionB、Bandwidth limitsC、Minimal signal lossD、No EMI

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考题 Dense Wavelength Division Multiplexing (DWDM) is an important innovation in optical networks.Which two descriptions best define DWDM?（）A、optical technology for transmitting up to 32 channels over multiple fiber strandsB、optical technology for transmitting up to 16 channels over multiple fiber strandsC、a WDM system that is compatible with EDFA technologyD、a technology for transmitting more closely packed optical signals using more sophisticated transceiver designs than CWDM .

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考题 The ultra long haul amplification technology used in ZXWM M900 system includes large-power （）technology and （）amplifier.

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考题 What two descriptions best define DWDM？（）A、 a WDM system that is compatible with EDFA technologyB、 an optical technology for transmitting up to 16 channels over multiple fiber strandsC、 an optical technology for transmitting up to 32 channels over multiple fiber strandsD、 a technology for transmitting multiple optical signals using less sophisticated transceiver designthen CWDME、 a technology for transmitting more closely packed optical signals using more sophisticatedtransceiver designs than CWDM

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考题单选题Possible phase relationships between voltage and current in an alternating current circuit include which of the following conditions?（）A Current and voltage may be in phaseB Current may lead the voltageC Current may lag the voltageD All of the above

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考题单选题The alternating current generator supplying a load has a voltage drop resulted from the loadWhen the load has a lagging power factor this voltage drop （）.A is smallB may be neglectedC is usefulD is considerable

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考题问答题Fuel Cells: 21st Century Electricity　　The 21st century’s leading energy source may very well depend on the development of a technology that was first discovered in 1839. Indeed, many experts believe that the future of electricity generation will not come from further refinement of solar, wind, coal or nuclear energy, but from fuel cells. Among the various types of fuel cells, the ceramic or solid oxide fuel cell promises to achieve the greatest efficiency of conversion of fossil fuels such as gas and coal to electricity while producing only very low levels of pollutants. To this end, a consortium comprising five leading organizations has established Ceramic Fuels Ltd, initially to expand fuel cell research and development and secondly, to bring the technology to commercial application.　　Ceramic fuel cells are electrochemical devices that directly convert fuels such as gasified coal or natural gas into electricity without the limitation of the Carnot cycle (an ideal thermodynamic cycle in which heat is taken onto a working fluid at a constant upper temperature and rejected at a constant lower temperature). In many respects, fuel cells work like batteries. As long as they are constantly supplied with fuel and oxidant, fuel cells can continuously produce power, removing the need for recharging.　　Fuel cells offer several advantages over traditional thermal power plants. The major difference between these two power generators is that the chemical energy of the fuel cell is converted directly to electrical power without intermediate conversion first to heat. The efficiency of a coal-fired thermal plant is typically in the range of 30%-35%. In a combined cycle gas turbine system running on natural gas, the maximum efficiency is in the range 45%-50%. Many experts believe high temperature fuel cells could reach efficiencies of 80%-85%. Ceramic fuel cells thus offer a more efficient and less polluting alternative to current power generation technologies.　　By-products from fuel cells are high quality heat, carbon dioxide and steam. The temperature of the exhaust gases is well above 500℃, meaning that solid oxide fuel cells are very attractive for electricity and heat generation as, in addition to supplying electricity, the leftover amounts of heat created during the process could be used to produce heat for industries, provide hot water supplies or warm buildings.　　Fuel cell technology is not new. In fact, the principles of fuel cell operation were first reported by British scientist Sir William Grove in 1839. His prototype used dilute sulphuric acid and operated at room temperature. Ceramic fuel cells developed much later, with the first one operating at 1000°C in 1937.　　Ceramic fuel cells offer many advantages over other energy systems:　　● they have the potential to produce electricity efficient from several fuel sources　　● they can generate large amounts of electricity　　● they are relatively quick to install　　Fuel cell research and development is extremely competitive worldwide, with the USA, Japan and some European countries leading the charge to commercialize this promising technology. For instance, a Dutch Belgian company has developed a fuel cell for a Volkswagen van and is also working on a larger unit to power a bus. Additionally, a German company is working on a fuel cell for the European space shuttle program and for submarines, while a Canadian company is evaluating a fuel cell to be used in small buses.　　Recent reports point to promising large international markets for ceramic fuel cells. Prospects for fuel cells in South East Asian markets appear good. Several countries, including Indonesia, Thailand and The Philippines are expected to demonstrate high rates of growth in demand for power an encouraging situation for those countries quick enough to develop and commercialize fuel cell technology.　　Energy is a vital component of a technology-based society and the growing need for electricity generation by the most efficient method will ensure a promising future for ceramic fuel cell technology. The Ceramic Fuel Cells Ltd initiative represents a major collaborative venture between public and private sectors. It is envisaged that this venture will go a long way towards achieving a greater efficiency of energy use worldwide.　　Do the following statements reflect the claims of the writer in the Reading Passage?　　YES　　　　　　　　 if the statement reflects the claims of the writer　　NO　　　　　　　　 if the statement contradicts the claims of the writer　　NOT GIVEN　　　　 if it is impossible to say what the writer thinks about this　　Statements:　　1．Sir William Grove was a physicist.　　2．Future transport vehicles may be powered by fuel cells.　　3．European companies were first in the race to develop fuel cell technology.　　4．Some rapidly developing South East Asian countries will soon market fuel cells.　　5．Cooperation between private companies and governments will encourage wider use of efficient energy sources.

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考题多选题You are the network consultant from passguide.com. You have been asked for which two features of optical networks allow data to be transmitted over extremely long distances? （）AEncryptionBBandwidth limitsCMinimal signal lossDNo EMI

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考题单选题（）is electricity that is flowing where it’s not supposed to through water, fittings on your boat, wet wood, damp surfaces, etc.A Stray currentB Rated currentC Starting currentD Earth current

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考题多选题What two descriptions best define DWDM？（）Aa WDM system that is compatible with EDFA technologyBan optical technology for transmitting up to 16 channels over multiple fiber strandsCan optical technology for transmitting up to 32 channels over multiple fiber strandsDa technology for transmitting multiple optical signals using less sophisticated transceiver designthen CWDMEa technology for transmitting more closely packed optical signals using more sophisticatedtransceiver designs than CWDM

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考题单选题The Owners to take over and pay all fuel remaining in the Vessel’s bunkers on re-delivery at current price at the port of redelivery，or at the nearest main bunkering port，if the bunker price at the port of redelivery is not available. This indicates that the Owners are to take over and pay the remaining bunkers（）.A at current price at the nearest main bunkering portB at current price at the port of redelivery if it is not available to obtain the current price at the nearest main bunkering portC at current price at the nearest main bunkering port if it is cheaper than that at the port of redeliveryD at current price at the port of redelivery if it is obtainable，even the price is higher at the nearest main bunkering port

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考题单选题In an alternating current electrical system, a low system power factor is a direct sign of （）A wasted energyB efficient operationC a short in the exciter field windingsD an excessive number of minor system grounds

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考题问答题过流（Over Current）故障

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考题单选题The frequency of the alternating current generated by a synchronous generator is governed by the speed and the（）A full excitationB loadC power factorD number of poles

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考题单选题What is implied in the first sentence?A Americans are better prepared for death than other people.B Americans enjoy a higher life quality than ever before.C Americans are over-confident of their medical technology.D Americans take a vain pride in their long life expectancy.

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考题单选题Many great scientists and inventors of the past, such as Nikola Tesla, has possessed the ability of extraordinary, visualization skills that enabled them to analyze the most minute details of complex machines before the devices were even constructed.A has possessed the ability of extraordinary visualization skillsB have been able to possess extraordinary visualization skillsC possessed skills in visualization that was extraordinaryD possessed extraordinary visualization skillsE possessed skills of visualizing that was extraordinary

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考题填空题Nikola Tesla invented alternating current technology that enabled electricity to be transmitted over long distances.____

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考题单选题Which of the following components are used to convert alternating current produced in the generator windings to direct current?（）A Armature and equalizerB Commutator and brushesC Rotor and interpolesD Field and exciter

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