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Correct CHOICE is (a) True

The best explanation: Case based REASONING begins with the identification of a case that best suits the case under INVESTIGATION. The case is then modified to suit the current situation. The modified case is evaluated based on performance. FINALLY, the new case is added to the case base according to the performance LEVEL.

Correct OPTION is (C) WEIGHTED

To elaborate: The connection between neurons or nodes is weighted. If the number associated with the weight is positive, then it is an excitatory condition. If the number associated with the weight is NEGATIVE, then it is an INHIBITORY condition.

Correct choice is (a) an incident, probable cause

For EXPLANATION: A BAYESIAN network examines an event and determines the PROBABILITY of a known cause activating that event. For example, a Bayesian network can be used to examine the symptoms of a PERSON and MATCH it with a probable disease.

Correct answer is (b) False

Explanation: Non coherent receivers REQUIRE less power than coherent receivers. This is because coherent receivers involve frequency and phase CORRECTION in their reception process. SINCE ADDITIONAL processes are carried out, more power is consumed. Similarly, higher symbol rate requires more PROCESSING speed, and consequently more power.

The correct OPTION is (b) Elasticity

Explanation: Elasticity DEFINES the amount of change constituted by the substitution of one parameter by another parameter. A VALUE of 1 indicates perfect substitution. Constant elasticity by substitution does not require independent input value and is suitable for MULTI objective analysis.

Right answer is (a) If-then rules

To elaborate: Expert systems are enriched with information and use reasoning to SOLVE complex decision MAKING PROBLEMS. The process is depicted with a set of if-then conditions instead of conventional PROCEDURAL CODE.

The correct CHOICE is (c) channel

Explanation: BIT error rate is DEFINED by the amount of bits received in error from the TOTAL number of bits received. Bit error rate primarily depends of channel type and modulation TECHNIQUE.

Correct OPTION is (b) Leave one out cross VALIDATION algorithm

Best explanation: The LEVEL of importance exhibited towards a parameter can be varied by adjusting the weights associated with each parameter. The degree of importance may be increased by increasing the value on scale. Leave one out cross validation algorithm is employed to learn the weights from the INSTANCES defined in the training set.

The correct option is (b) repeated single OBJECTIVE, DOMINANT

The best I can explain: Repeated single objective involves OPERATING on the same SET of members MULTIPLE times using single, different objective each time. The dominant members from each test are recorded for final analysis of Pareto set.

Right CHOICE is (b) False

For EXPLANATION I would say: MINIMUM SHIFT KEYING does not experience phase discontinuities because frequency changes occur at the carrier zero crossing points. This is expressed by setting the modulation index to 0.5.

Correct option is (d) Pareto boundary

Best explanation: A set of Pareto optimal SOLUTIONS is REFERRED to asPareto boundary or Pareto frontier. The Pareto front of a multi-objective optimisation is bounded by nadir objective VECTOR and IDEAL objective vector.

Right option is (a) Resources are used only to satisfy needs

Easy explanation: The UTILIZATION of resources by each node is MONITORED with a GLOBAL perspective of optimising radio resources. It should be done without compromising the quality of service available to the user and avoid over usage of resources.

The CORRECT answer is (c) OBJECTIVE, each variable

Easiest explanation: The objective function PROVIDES the share of each variable to the parameter to be optimised.The objective function is given by the product of objective coefficient and DECISION variable. The physical layer is described in terms of objective functions for RADIO resource optimisation.

Correct option is (d) Knowledge base and inference engine

For explanation I would say: Knowledge base is a large STORAGE of FACTS and rules obtained from experts of a domain. Inference engine USES the knowledge to deduce new solutions and resolve the query PRESENTED by the user.

Right OPTION is (b) SATE sequence

The EXPLANATION: In a hidden Markov model, the STATE is not directly available to the observer. The output, dependant on the state, is available. The parameters of the model are not hidden, and the model is referred to as hidden Markov model EVEN when the parameters are explicitly available.

The CORRECT option is (a) Rth=kRs where Rs is SYMBOL rate

Explanation: The simple expression of throughput objective is given by Rth=kRs . The COMPLEXITIES involved in the measurement of throughput are due to restricted retransmissions and no coding. As a result, a SINGLE BIT error leads to packet error. By taking this into account, the expression of throughput is given by Rth=Rb(1-Pe)^l.

The correct choice is (c) Two root raised cosine filter, one raised cosine filter

Easy EXPLANATION: Two root raised cosine filter is required to FORM one raised cosine filter. It may be USED to reduce inter-symbol interference. It involves installing one root raised cosine filter at the transmitter and the other filter at the receiver.

The correct option is (b) Fitness function

For explanation I WOULD SAY: Fitness solution determines the degree of closeness exhibited by the designed solution to the specified expectations as a single FIGURE of merit. Evolutionary ALGORITHM determines optimal solutions by eliminating sub-optimal solutions based on the figure of merit ASSIGNED by fitness solutions.

Right answer is (d) SIGNAL classification

To explain: HIDDEN Markov models use past data to predict future actions. It may be used to describe channel quality. It determines whether the PROCESS should move to the next or remain in the present state. The current channel statistics may be modelled and use for DECISION MAKING in cellular network.

Correct option is (c) UTILITY

Easy explanation: In multi OBJECTIVE analysis, single utility function INVOLVES combining SEVERAL objectives into a single number. Ranks are assigned to solutions. The solution that MAXIMIZES utility function is selected.

Correct option is (d) a priori method

To elaborate: A priori method requires setting up of certain amount of DESIRED traits before optingthe solution process.When no desired traits are specified in MULTI objective OPTIMISATION, it is REGARDED as no-preference method.

The correct option is (b) signal to noise ratio

Best EXPLANATION: Cognitive RADIO sets the TRANSMITTED power. The transmitted power, the path loss, and the noise floor can be used to compute received power and noise power. SNR is an important FACTOR in this CALCULATION.

The correct choice is (a) BER and bandwidth

Explanation: DIRECT dependency INVOLVES the one to one relationship between two parameters. Indirect dependency involves creating links between parameters based on OBJECTIVE dependency. Bit error rate directly depends on bandwidth and is indirectly related to SIGNAL to noise RATIO.

The correct option is (d) Case based reasoning

Best explanation: Case based reasoning is the process of developing solutions to current PROBLEMS based on solutions that have ALREADY been applied under similar CONDITIONS. The process initially involves the COMPARISON of functional and operational characteristics for resemblance. If the similarity is limited, then reasoning is applied for modification of solution to suit the current problem.

Right choice is (b) POSTERIOR distribution, probabilistic inference

For explanation: The process of COMPUTING the posterior distribution of variables when provided with supporting conditions is called probabilistic inference. It is probability of one or more variable TAKING a PARTICULAR set of values.

Correct option is (b) Fuzzy logic USES only accurate information

For EXPLANATION I WOULD say: Fuzzy logic is based on the observation that decision making sometimes involves making use of inaccurate and imprecise information. The fuzzy logic models are generally vague but are capable of IDENTIFYING, representing, and modifying unclear information and DATA.

Correct choice is (c) MULTIPLE single objective Pareto sampling, objectives, ranks

Best explanation: Multiple single objective Pareto sampling CALCULATES all objectives for each member of the population. A matrix is built with columns REPRESENTING the objectives, and the rows represent individual RANK for each objective.

Right option is (d) linear LOGARITHMIC function

The best I can EXPLAIN: Cobb Douglas function is otherwise CALLED linear logarithmic function. It is an advanced version of weighted SUM approach. The result is SHAPED by the logarithmic function. The logarithmic function adds convexity to the optimisation curve.

The correct choice is (d) Throughput

Easy explanation: DATA rate is a measure of rate at which data arrives regardless of transmission errors. Throughput is the measure GOOD INFORMATION available at the receiver.

The correct choice is (a) low symbol rate

Easy EXPLANATION: The minimisation of BANDWIDTH causes low symbol rate and utilization of algorithm such GMSK. The maximisation of bandwidth causes HIGH symbol rate and HIGHER modulation method.

Correct choice is (b) directed acyclic graph

To elaborate: A Bayesian network is a probabilistic GRAPHICAL model where a group of VARIABLES and their conditional DEPENDENCIES are represented USING directed acyclic graph. Directed acyclic graph is a directed graph and does not have directed cycles.

Right option is (b) ratio of signal power to SUM of NOISE and INTERFERENCE power

The best explanation: Signal to interference plus noise ratio is DEFINED as ratio of signal power to sum of noise and interference power. If the noise power were to be zero, the expression reduces to signal to interference ratio. If the interference were to be zero, the expression reduces to signal to noise ratio.

Right answer is (a) Root raised cosine filter

To elaborate: The raised cosine filter is an IMPLEMENTATION of NYQUIST low pass filter. It is USED for pulse shaping and to minimise inter-symbol interference. It derives its name from the frequency spectrum which resembles a cosine FUNCTION.

The correct choice is (d) Power

The explanation is: BANDWIDTH measures the CAPACITY of spectrum used by the radio. It influences a number of objects such as bit error rate, interference power, throughput, and spectral efficiency. MODULATION type, SYMBOL rate, and pulse SHAPE filter are control monitors.

Correct choice is (a) continuous, Markov process

The best I can explain: A Markov CHAIN is a stochastic model. It represents a progression of EVENTS in which the probability of each EVENT DEPENDS on the state achieved by the PAST event.

The correct choice is (a) True

Best explanation: GAUSSIAN minimum shift keying involves Gaussian FILTERING the modulating signal and passing it through frequency modulator. The second METHOD uses quadrature modulator otherwise KNOWN as I-Q modulator.

Correct option is (c) Linguistic variables

For explanation: Linguistic variables are assigned non-numerical values to AID the representation of facts and rules. For example, a linguistic variable MAY take “hot” and “COLD” as input. In order to take advantage of the scale offered by fuzzy logic, additional words such as “RATHER” or “SOMEWHAT” may be used.

The correct ANSWER is (b) Connectionistic

Best EXPLANATION: The DISTRIBUTED signal activity being carried out at once through connections may be represented using numbers. The connection is improved based on collected information over TIME and this PROCESS is referred to as learning.

The correct OPTION is (a) product of input power to the antenna and gain of the antenna

Easy explanation: Effective isotropic radiated power measures the combination of the power EMITTED by the transmitter and the CAPABILITY of the antenna to WIELD that power in a particular direction. It is given by the product of product of input power to the antenna and gain of the antenna.