Virtual memory is : ?->(Show Answer!)

1. Virtual memory is :

Answer: An illusion of extremely large main memory.

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QA->Virtual memory is :....

QA->The size of the virtual memory depends on the size of :....

QA->In a memory, the minimum time delay between the initiation of successive memory operations is:....

QA->A byte addressable computer has memory capacity of 4096 KB and can perform 64 operations. An instruction involving 3 memory operands and one operator needs:....

QA->A computer with a 32 bit wide data bus implements its memory using 8 K x 8 static RAM chips. The smallest memory that this computer can have is:....

MCQ-> Read the following passage carefully and answer the given questions. Certain words/phrases have been given in bold to help you locate them while answering some of the questions. Virtual currencies are growing in popularity. While the collective value of virtual currencies is still a fraction of the total U.S. Dollars in circulation, the use of virtual currencies as a payment mechanism of transfer of value is gaining momentum. Additionally, the number of entities (issuers, exchangers and intermediaries, to name just a few) that engage in virtual currency transactions is increasing and these entities often need access to traditional banking services.Virtual currencies are digital representations of value that function as a medium of exchange, a unit of account and a store of value (buy now redeem later policy). In many cases, virtual currencies are “convertible” currencies; they are not legal lenders, but they have an equivalent value in real currency. Despite what seems to be a tremendous interest in virtual currencies their overall value is still extremely small relative to other payment mechanisms, such as cash, cheques and credit and debit cards. The virtual currency landscape includes many participants from the merchant that accepts the virtual currency, to the intermediary that exchanges the virtual currency on behalf of the merchant, to the exchange that actually converts the virtual currency to the real currency to the electronic wallet provider that holds the virtual currency on behalf of its owner. Accordingly, opportunities abound for community banks to provide services to entities engaged in virtual currency activities. Eventually, it is also possible that community banks may find themselves holding virtual currency on their own balance sheets.Launched in 2009, Silicon is currently the largest and most popular virtual currency. However, many other virtual currencies have emerged over the past few years, such as Litecoin, Dogecoin, Peercoin and these provide even more anonymity to its users than that provided by Bitcoin.As the virtual currency landscape is fraught with dangers, what important risks should community bankers consider?The most significant is compliance risk- a subset of legal risk. Specifically, virtual currency administrators or legal exchangers may present risks similar to other money transmitters, as well in presenting their own unique risks. Quite simply, many users of virtual currencies do so because of the perceptions that transactions conaucted using virtual currencies are anonymous. The less-than transparent nature of the transactions, :nay make it more difficult for a inancial institution to truly know and understand the activities of its customer and whether the customer’s activities are legal. Therefore, these transactions may present a higher risk for banks and require additional due diligence and monitoring.Another important risk for community banks to consider is credit risk. How should a community bank respond if a borrower wants to specifically post Bitcoin or another virtual currency as collateral for a loan? For many, virtual currencies are simply another form of cash, so it is not hard to analyse that bankers will face such a scenario at some point. In this case, caution is appropriate. Bankers should carefully weigh the pros and cons of extending any loan secured by Bitcoin or other virtual currencies (in whole or in part), or where the source of loan repayment is in some way dependent on the virtual currency. For one, the value of Bitcoin in particular has been volatile. Then, the collateral value could fluctuate widely from day-to-day. Bankers also need to think about control over the account. ‘How does the banker control access to a virtual wallet, and how can it control the borrower’s access to the virtual wallet? In the event of a loan default, the bank would need to take control of the virtual currency. This would require access to the borrower’s virtual wallet and private key. All of this suggests that the loan agreement needs to be carefully crafted and that additional steps need to be taken to ensure the bank has a perfected lift on the virtual currency.Virtual currencies bring with them, both opportunities and challenges, and they are likely here to stay. Although, it is too early to determine just how prevalent they will be in the coming years, we too expect that the virtual participants in the virtual currency ecosystem will increasingly intersect with the banking industry.Which of the following is the meaning of the phrase ‘fraught with dangers’ as mentioned in the passage?
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MCQ-> In a modern computer, electronic and magnetic storage technologies play complementary roles. Electronic memory chips are fast but volatile (their contents are lost when the computer is unplugged). Magnetic tapes and hard disks are slower, but have the advantage that they are non-volatile, so that they can be used to store software and documents even when the power is off.In laboratories around the world, however, researchers are hoping to achieve the best of both worlds. They are trying to build magnetic memory chips that could be used in place of today’s electronics. These magnetic memories would be nonvolatile; but they would also he faster, would consume less power, and would be able to stand up to hazardous environments more easily. Such chips would have obvious applications in storage cards for digital cameras and music- players; they would enable handheld and laptop computers to boot up more quickly and to operate for longer; they would allow desktop computers to run faster; they would doubtless have military and space-faring advantages too. But although the theory behind them looks solid, there are tricky practical problems and need to be overcome.Two different approaches, based on different magnetic phenomena, are being pursued. The first, being investigated by Gary Prinz and his colleagues at the Naval Research Laboratory (NRL) in Washington, D.c), exploits the fact that the electrical resistance of some materials changes in the presence of magnetic field— a phenomenon known as magneto- resistance. For some multi-layered materials this effect is particularly powerful and is, accordingly, called “giant” magneto-resistance (GMR). Since 1997, the exploitation of GMR has made cheap multi-gigabyte hard disks commonplace. The magnetic orientations of the magnetised spots on the surface of a spinning disk are detected by measuring the changes they induce in the resistance of a tiny sensor. This technique is so sensitive that it means the spots can be made smaller and packed closer together than was previously possible, thus increasing the capacity and reducing the size and cost of a disk drive. Dr. Prinz and his colleagues are now exploiting the same phenomenon on the surface of memory chips, rather spinning disks. In a conventional memory chip, each binary digit (bit) of data is represented using a capacitor-reservoir of electrical charge that is either empty or fill -to represent a zero or a one. In the NRL’s magnetic design, by contrast, each bit is stored in a magnetic element in the form of a vertical pillar of magnetisable material. A matrix of wires passing above and below the elements allows each to be magnetised, either clockwise or anti-clockwise, to represent zero or one. Another set of wires allows current to pass through any particular element. By measuring an element’s resistance you can determine its magnetic orientation, and hence whether it is storing a zero or a one. Since the elements retain their magnetic orientation even when the power is off, the result is non-volatile memory. Unlike the elements of an electronic memory, a magnetic memory’s elements are not easily disrupted by radiation. And compared with electronic memories, whose capacitors need constant topping up, magnetic memories are simpler and consume less power. The NRL researchers plan to commercialise their device through a company called Non-V olatile Electronics, which recently began work on the necessary processing and fabrication techniques. But it will be some years before the first chips roll off the production line.Most attention in the field in focused on an alternative approach based on magnetic tunnel-junctions (MTJs), which are being investigated by researchers at chipmakers such as IBM, Motorola, Siemens and Hewlett-Packard. IBM’s research team, led by Stuart Parkin, has already created a 500-element working prototype that operates at 20 times the speed of conventional memory chips and consumes 1% of the power. Each element consists of a sandwich of two layers of magnetisable material separated by a barrier of aluminium oxide just four or five atoms thick. The polarisation of lower magnetisable layer is fixed in one direction, but that of the upper layer can be set (again, by passing a current through a matrix of control wires) either to the left or to the right, to store a zero or a one. The polarisations of the two layers are then either the same or opposite directions.Although the aluminum-oxide barrier is an electrical insulator, it is so thin that electrons are able to jump across it via a quantum-mechanical effect called tunnelling. It turns out that such tunnelling is easier when the two magnetic layers are polarised in the same direction than when they are polarised in opposite directions. So, by measuring the current that flows through the sandwich, it is possible to determine the alignment of the topmost layer, and hence whether it is storing a zero or a one.To build a full-scale memory chip based on MTJs is, however, no easy matter. According to Paulo Freitas, an expert on chip manufacturing at the Technical University of Lisbon, magnetic memory elements will have to become far smaller and more reliable than current prototypes if they are to compete with electronic memory. At the same time, they will have to be sensitive enough to respond when the appropriate wires in the control matrix are switched on, but not so sensitive that they respond when a neighbouring elements is changed. Despite these difficulties, the general consensus is that MTJs are the more promising ideas. Dr. Parkin says his group evaluated the GMR approach and decided not to pursue it, despite the fact that IBM pioneered GMR in hard disks. Dr. Prinz, however, contends that his plan will eventually offer higher storage densities and lower production costs.Not content with shaking up the multi-billion-dollar market for computer memory, some researchers have even more ambitious plans for magnetic computing. In a paper published last month in Science, Russell Cowburn and Mark Well and of Cambridge University outlined research that could form the basis of a magnetic microprocessor — a chip capable of manipulating (rather than merely storing) information magnetically. In place of conducting wires, a magnetic processor would have rows of magnetic dots, each of which could be polarised in one of two directions. Individual bits of information would travel down the rows as magnetic pulses, changing the orientation of the dots as they went. Dr. Cowbum and Dr. Welland have demonstrated how a logic gate (the basic element of a microprocessor) could work in such a scheme. In their experiment, they fed a signal in at one end of the chain of dots and used a second signal to control whether it propagated along the chain.It is, admittedly, a long way from a single logic gate to a full microprocessor, but this was true also when the transistor was first invented. Dr. Cowburn, who is now searching for backers to help commercialise the technology, says he believes it will be at least ten years before the first magnetic microprocessor is constructed. But other researchers in the field agree that such a chip, is the next logical step. Dr. Prinz says that once magnetic memory is sorted out “the target is to go after the logic circuits.” Whether all-magnetic computers will ever be able to compete with other contenders that are jostling to knock electronics off its perch — such as optical, biological and quantum computing — remains to be seen. Dr. Cowburn suggests that the future lies with hybrid machines that use different technologies. But computing with magnetism evidently has an attraction all its own.In developing magnetic memory chips to replace the electronic ones, two alternative research paths are being pursued. These are approaches based on:
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MCQ->Which of the following are necessary for Run-time Polymorphism? The overridden base method must be virtual, abstract or override. Both the override method and the virtual method must have the same access level modifier. An override declaration can change the accessibility of the virtual method. An abstract inherited property cannot be overridden in a derived class. An abstract method is implicitly a virtual method....

MCQ->As mentioned in the passage,banks may face which of the following risks while dealing with virtual currencies? (A) Since these transactions are largely untraceable, virtual currencies may be misused for criminal activities. (B) The price of virtual currencies including Bitcoin is subject to significant fluctuations. (C) There are few designated ATMs from which one can withdraw such currencies....

MCQ-> Analyse the following passage and provide appropriate answers that follow.We can answer Fermi’s Paradox in two ways. Perhaps our current science over - estimates the likelihood of extraterrestrial intelligence evolving. Or, perhaps, evolved technical intelligence has some deep tendency to be self - limiting, even self - exterminating. After Hiroshima, some suggested that any aliens bright enough to make colonizing space ships would be bright enough to make thermonuclear bombs, and would use them on each other sooner or later.I suggest a different, even darker solution to the Paradox. Basically, I think the aliens forget to send radio signals or colonize space because they’re too busy with runaway consumerism and virtual - reality narcissism. Once they turn inwards to chase their shiny pennies of pleasure, they lose the cosmic plot.The fundamental problem is that an evolved mind must pay attention to indirect cues of biological fitness, rather than tracking fitness itself. This was a key insight of evolutionary psychology in the early 1990s; although evolution favours brains that tend to maximize fitness (as measured by numbers of great - grandkids), no brain has capacity enough to do so under every possible circumstance. As a result, brains must evolve shortcuts: fitness - promoting tricks, cons, recipes and heuristics that work, on an average, under ancestrally normal conditions. Technology is fairly good at controlling external reality to promote real biological fitness, but it’s even better at delivering fake fitness - subjective cues of survival and reproduction without the real - world effects.Fitness - faking technology tends to evolve much faster than our psychological resistance to it. With the invention of Xbox 360, people would rather play a high - resolution virtual ape in Peter Jackson’s King Kong than be a perfect – resolution real human. Teens today must find their way through a carnival of addictively fitness - faking entertainment products. The traditional staples of physical, mental and social development - athletics, homework dating - are neglected. The few young people with the self - control to pursue the meritocratic path often get distracted at the last minute.Around 1900, most inventions concerned physical reality and in 2005 focus shifted to virtual entertainment. Freud’s pleasure principle triumphs over the reality principle. Today we narrow - cast human - interest stories to each other, rather than broadcasting messages of universal peace and progress to other star systems.Maybe the bright aliens did the same. I suspect that a certain period of fitness - faking narcissism is inevitable after any intelligent life evolves. This is the Great Temptation for any technological species – to shape their subjective reality to provide the cues of survival and reproductive success without the substance. Most bright alien species probably go extinct gradually, allocating more time and resources to their pleasures and less to their children.Heritable variation in personality might allow some lineages to resist the Great Temptation and last longer. Some individuals and families may start with an “irrational” Luddite abhorrence of entertainment technology, and they may evolve ever more self - control, conscientiousness and pragmatism by combining the family values of the religious right with the sustainability values of the Greenpeace. They wait patiently for our fitness - faking narcissism to go extinct. Those practical - minded breeders will inherit the Earth as like - minded aliens may have inherited a few other planets. When they finally achieve contacts, it will not be a meeting of novel - readers and game - players. It will be a meeting of dead - serious super - parents who congratulate each other on surviving not just the Bomb, but the Xbox.Among the following options, which one represents the most important concern raised in the passage?
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