answer all

For a floating-point implementation with p = 4, = 10, explain the round to even method of rounding using the half-way cases 7.3125, 7.3175 as examples. To illustrate how their modes of operation work, we can use instead a pseudo-random permutation that operates on the 26 letters of the English alphabet: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 m A B C D E F G H I J K L M N O P Q R S T U V W X Y Z EK(m) P K X C Y W R S E J U D G O Z A T N M V F H L I B Q As the XOR operation is not defined on the set {A, . . . , Z}, we replace it here during encryption with modulo-26 addition (e.g., C D = F and Y C = A). (a) Encrypt the plaintext "TRIPOS" using: (i) electronic codebook mode; [2 marks] (ii) cipher-block chaining (using IV c0 = K); [4 marks] In the process of using functional dependencies to normalise a schema, what is meant by a lossless join decomposition and how is such a decomposition guaranteed? [4 marks] (d) In schema normalisation, is Boyce-Codd Normal Form (BCNF) always to be preferred over 3rd Normal Form (3NF)? Explain your answer. [4 marks] 7 (TURN OVER) CST.2014.4.8 7 Economics, Law and Ethics (a) Describe the provisions of the Data Protection Act. [8 marks] Discuss to what extent a programmer can expect a program that conforms to a standard to generate identical results when run under different conforming compilers on different machines. [6 marks] (b) ALGOL 60 provided call by value and call by name, Pascal provided call by value and call by reference, and ALGOL-W provided a variety of calling methods including call by result and call by value-result. Briefly describe the calling mechanisms just mentioned and discuss why most modern programming languages provide only call by value. [8 marks] Using the qualities of the organization portrayed above, plan a convention for disseminating this data across the organization. It would be ideal for you to determine the configuration of your messages and the size of any message fields This question connects with double requirement fulfillment issues (CSPs). A CSP has a set. It will contain the precomputed values for this inquiry. In this way the normal and costly question can be responded to by a solitary key-based peruse. You are designing and are about to launch a mobile phone app which will seek to understand the emotional condition of the user, using multiple inputs such as motion sensing, facial expression recognition, voice stress measurement and the analysis of entered text. Its declared purpose is to enable services to interact more empathically with users. [5 marks] Discuss the reasons why languages such as Fortran, Algol and PL/I designed in 1950s and 1960s are less widely used than languages designed in the last 20 years. [6 marks] 3 [TURN OVER CST.2004.3.4 5 Operating Systems II What problem do real-time scheduling algorithms try to solve? [2 marks] (Note: Sum ought to be 0 on the off chance that no matching records exist.) (a) Explain how the activity embed What functions can we obtain from these via currying? [6 marks] (b) Consider the function zarg defined below: fun zarg f ([], e) = e | zarg f (x::xs, e) = f(x, zarg f (xs,e)); Show that with the help of this function, it is possible to an expression for the sum of a given list of integers. Then describe what zarg does in general. [4 marks] What is the state transition diagram for this mystery module?

Consider the two nuclear reactions

A+BC+EC+DF+GA+BC+EC+DF+G

(a) Show that the net disintegration energy for these two reactions(Qnet=Q1+QI)(Qnet=Q1+QI)is identical to the disintegration energy for the net reaction

A+B+DE+F+GA+B+DE+F+G

(b) One chain of reactions in the proton-proton cycle in the Sun's core is

11H+11H21H+01e+01e+01e211H+11H12H+10e+10e+10e2

11H+21H32He+11H+12H23He+

11H+32He42He+01e+11H+23He24He+10e+

01e+01e210e+10e2

Based on part (a), what isQnetQnetfor this sequence?

Natural uranium must be processed to produce uranium enriched in235U235Ufor weapons and power plants. The processing yields a large quantity of nearly pure238U238Uas a by-product, called "depleted uranium." Because of its high mass density, 238UUis used in armor-piercing artillery shells. (a) Find the edge dimension of a70.0kg70.0kgcube of238U238U(=19.1103kg/m3).(=19.1103kg/m3).(b) The isotope238U238Uhas a long half-life of4.471094.47109y. As soon as one nucleus decays, a relatively rapid series of 14 steps begins that together constitute the net reaction

23892U8(42He)+6(01e)+20682Pb+6+Qnet92238U8(24He)+6(10e)+82206Pb+6+Qnet

Find the net decay energy. (Refer to Table44.2.)(c)44.2.)(c)Argue that a radioactive sample with decay rateRRand decay energyQQhas power outputP=QR.P=QR.(d) Consider an artillery shell with a jacket of 70.0kgkgof238U238U. Find its power output due to the radioactivity of the uranium and its daughters. Assume the shell is old enough that the daughters have reached steady-state amounts. Express the power in joules per year. (e) What If? A 17 -year-old soldier of mass 70.0kgkgworks in an arsenal where many such artillery shells are stored. Assume his radiation exposure is limited to 5.00 rem per year. Find the rate in joules per year at which he can absorb energy of radiation. Assume an averageRBERBEfactor of1.10.1.10.

The first nuclear bomb was a fissioning mass of plutonium- 239 that exploded in the Trinity test before dawn on July16,1945,16,1945,at Alamogordo, New Mexico. Enrico Fermi was 14kmkmaway, lying on the ground facing away from the bomb. After the whole sky had flashed with unbelievable brightness, Fermi stood up and began dropping bits of paper to the ground. They first fell at his feet in the calm and silent air. As the shock wave passed, about 40ssafter the explosion, the paper then in flight jumped approximately 2.5mmaway from ground zero. (a) Equation 17.10 describes the relationship between the pressure amplitudePmaxPmaxof a sinusoidal air compression wave and its displacement amplitudesmaxsmax. The compression pulse produced by the bomb explosion was not a sinusoidal wave, but let's use the same equation to compute an estimate for the pressure amplitude, taking1s11s1as an estimate for the angular frequency at which the pulse ramps up and down. (b) Find the change in volumeVVof a sphere of radius 14kmkmwhen its radius increases by2.5m.2.5m.(c) The energy carried by the blast wave is the work done by one layer of air on the next as the wave crest passes. An extension of the logic used to derive Equation 20.8 shows that this work is given by(Pmax)(V).(Pmax)(V).Compute an estimate for this energy. (d) Assume the blast wave carried on the order of one-tenth of the explosion's energy. Make an order-of-magnitude estimate of the bomb yield. (e) One ton of exploding TNT releases 4.2GJGJof energy. What was the order of magnitude of the energy of the Trinity test in equivalent tons of TNT? Fermi's immediate knowledge of the bomb yield agreed with that determined days later by analysis of elaborate measurements.

Another series of nuclear reactions that can produce energy in the interior of stars is the carbon cycle first proposed by Hans Bethe in 1939, leading to his Nobel Prize in Physics in 1967. This cycle is most efficient when the central temperature in a star is above1.6107K1.6107K. Because the temperature at the center of the Sun is only1.5107K1.5107K, the following cycle produces less than 10%%of the Sun's energy. (a) A high-energy proton is absorbed by12C12C. Another nucleus,A,A,is produced in the reaction, along with a gamma ray. Identify nucleusA.A.(b) NucleusAAdecays through positron emission to form nucleusBB. Identify nucleusBB(c) NucleusBBabsorbs a proton to produce nucleus C and a gamma ray. Identify nucleusCC. (d) Nucleus C absorbs a proton to produce nucleusDDand a gamma ray. Identify nucleusD.D.(e) NucleusDDdecays through positron emission to produce nucleusE.E.Identify nucleusE.E.(f) NucleusEEabsorbs a proton to produce nucleusFFplus an alpha particle. Identify nucleusFF. (g) What is the significance of the final nucleus in the last step of the cycle outlined in part (f)?

You want to find out how many atoms of the isotope 65CuCuare in a small sample of material. You bombard the sample with neutrons to ensure that on the order of 1%%of these copper nuclei absorb a neutron. After activation, you turn off the neutron flux and then use a highly efficient detector to monitor the gamma radiation that comes out of the sample. Assume half of the 66CuCunuclei emit a 1.04 -MeV gamma ray in their decay. (The other half of the activated nuclei decay directly to the ground state of66Ni.)66Ni.)If after 10minmin(two half-lives) you have detected1.00104MeV1.00104MeVgamma ray in their decay. (The other half of the activated nuclei decay directly to the ground state of 66NiNi. If after 10 min (two half-lives) you have detected1.00104MeV1.00104MeVof photon energy at1.04MeV,(a)1.04MeV,(a)approximately how many 65CuCuatoms are in the sample? (b) Assume the sample contains natural copper. Refer to the isotopic abundances listed in Table 44.2 and estimate the total mass of copper in the sample.

A certain nuclear plant generates internal energy at a rate of 3.065GWGWand transfers energy out of the plant by electrical transmission at a rate of 1.000GWGW. Of the waste energy, 3.0%%is ejected to the atmosphere and the remainder is passed into a river. A state law requires that the river water be warmed by no more than3.50C3.50Cwhen it is returned to the river. (a) Determine the amount of cooling water necessary (in kilograms per hour and cubic meters per hour) to cool the plant. (b) Assume fission generates7.801010J/g7.801010J/gof235U235U. Determine the rate of fuel burning (in kilograms per hour) of255U.255U.

(a) Calculate the energy (in kilowatt-hours) released if 1.00kgkgof 239PuPuundergoes complete fission and the energy released per fission event is 200MeVMeV. (b) Calculate the energy (in electron volts) released in the deuterium-tritium fusion reaction

21H+31H42He+10n21H+13H24He+01n

(c) Calculate the energy (in kilowatt-hours) released if 1.00kgkgof deuterium undergoes fusion according to this reaction. (d) What If? Calculate the energy (in kilowatt-hours) released by the combustion of 1.00kgkgof carbon in coal if eachC+O2CO2C+O2CO2reaction yields 4.20eVeV. (e) List advantages and disadvantages of each of these methods of energy generation.

(a) At timet=0t=0, a sample of uranium is exposed to a neutron source that causesN0N0nuclei to undergo fission. The sample is in a supercritical state, with a reproduction constantK>1K>1. A chain reaction occurs that proliferates fission throughout the mass of uranium. The chain reaction can be thought of as a succession of generations. TheN0N0fissions produced initially are the zeroth generation of fissions. From this generation,N0KN0Kneutrons go off to produce fission of new uranium nuclei. TheN0KN0Kfissions that occur subsequently are the first generation of fissions, and from this generationN0K2N0K2neutrons go in search of uranium nuclei in which to cause fission. The subsequentN0K2N0K2fissions are the second generation of fissions. This process can continue until all the uranium nuclei have fissioned. Show that the cumulative total of fissionsNNthat have occurred up to and including thennth generation after the zeroth generation is given by

N=N0(Kn+11K1).N=N0(Kn+11K1).

(b) Consider a hypothetical uranium weapon made from5.50kg5.50kgof isotopically pure235U235U. The chain reaction has a reproduction constant of1.101.10and starts with a zeroth generation of1.0010201.001020fissions. The average time interval between one fission generation and the next is10.0ns10.0ns. How long after the zeroth generation does it take the uranium in this weapon to fission completely? (c) Assume the bulk modulus of uranium is 150 GPa. Find the speed of sound in uranium. You may ignore the density difference between235U235Uand natural uranium. (d) Find the time interval required for a compressional wave to cross the radius of a5.505.50-kg sphere of uranium. This time interval indicates how quickly the motion of explosion begins. (e) Fission must occur in a time interval that is short compared with that in part (d); otherwise, most of the uranium will disperse in small chunks without having fissioned. Can the weapon considered in part (b) release the explosive energy of all its uranium? If so, how much energy does it release in equivalent tons of TNT? Assume one ton of TNT releases4.204.20GJ and each uranium fission releases200MeV200MeVof energy.