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This paper presents an analysis of the performance of the Energy Aware Scheduling Algorithm (EASA) in a 5G green communication system. 5G green communication systems rely on EASA to manage resource sharing. The aim of the proposed model is to improve the efficiency and energy consumption of resource sharing in 5G green communication systems. The main objective is to address the challenges of achieving optimal resource utilization and minimizing energy consumption in these systems. To achieve this goal, the study proposes a novel energy‐aware scheduling model that takes into consideration the specific characteristics of 5G green communication systems. This model incorporates intelligent techniques for optimizing resource allocation and scheduling decisions, while also considering energy consumption constraints. The methodology used involves a combination of mathematical analysis and simulation studies. The mathematical analysis is used to formulate the optimization problem and design the scheduling model, while the simulations are used to evaluate its performance in various scenarios. The proposed EASM reached a 91.58% false discovery rate, a 64.33% false omission rate, a 90.62% prevalence threshold, and a 91.23% critical success index. The results demonstrate the effectiveness of the proposed model in terms of reducing energy consumption while maintaining a high level of resource utilization. [ABSTRACT FROM AUTHOR]

This paper proposes the prediction method of differential mode noise transmitted to the input power of a single‐phase inverter in a high‐frequency model. A high‐frequency equivalent circuit considering the parasitic impedance is proposed. This paper presents a method to measure the parasitic impedance included in the DC link capacitor and insulated‐gate bipolar transistor (IGBT) using a network analyser and extract the parasitic impedance included in the DC bus plate and PCB using Q3D. A mathematical analysis is proposed by applying the double integral Fourier form to the current noise sources, and a method for obtaining differential‐mode noise by analysing the impedance path is proposed. The switching of IGBT is modelled as the noise current source that reflects the pulse width modulation (PWM) duty change using the double integral Fourier form. The impedance path of differential mode noise transmitted to the input is mathematically analysed. The differential mode noise affecting the input is modelled by multiplying the impedance path and the noise source current. The validity of the proposed high‐frequency equivalent circuit and the mathematical analysis is verified by the less than 5% error in the resonant frequency of the derived differential mode noise voltage and the resonant frequency measured experimentally. [ABSTRACT FROM AUTHOR]

The purpose of this study is to provide further empirical evidence for the Australian case. It differs from previous studies in a number of respects. For example, the process by which expectations are generated differs from the processes adopted in previous studies. It also has two additional aims which differentiate it from earlier studies. First, it considers the validity of aggregating the demands for certain monetary assets into a single demand for money function. Most of the studies mentioned above deal with a single monetary aggregate; Lewis and Wallace consider only the demand for savings deposits. This study reports separate equations explaining the demand for notes and coin and current (cheque) deposits. These assets have been chosen because they possess the common characteristic that they can be converted into cash on demand. Secondly, an aspect of the Australian banking system which has been ignored in previous studies is examined in this paper. Australian trading banks lend on the overdraft system and at any point in time there is a substantial amount available to borrowers in the unused portions of their overdraft accounts. It has frequently been argued that the value of this store of liquidity should be included in measures of the money supply. This proposition is tested by the equations reported in this paper. [ABSTRACT FROM AUTHOR]

The inter‐turn short‐circuit fault of a power transformer has a large current in the winding, which will cause serious heating and deformation of the winding and may threaten the safety of the power transformer. Under this background, this paper proposes a scheme based on open‐delta voltage monitoring and identification of inter‐turn short circuits in power transformers. First, the mathematical modeling and analysis of the principle of inter‐turn short‐circuit monitoring of power transformers are carried out, and the mathematical expression to characterize power transformers with different short‐circuit turns are given. Second, the magnetic field distribution of the power transformer under different short‐circuit conditions, the relationship between the eigenvalue and the number of short‐circuit turns etc. are given. Finally, the experimental study verifies the correctness of the proposed scheme. [ABSTRACT FROM AUTHOR]

In this paper, an improved time‐domain analytical method for LLC resonant converters is proposed. Unlike traditional time‐domain analytical methods, the resonant current in the dead time is derived by considering the equivalent capacitances of the switching devices and the transformer. The equivalent output capacitance of the primary‐side switch is calculated by using a two‐segment fitting approach. The equivalent capacitance of the transformer is calculated by using the six‐capacitor model. The current increment method is used to calculate the initial value of the magnetizing current and to determine the numerical calculation conditions for the proposed time‐domain expressions. Finally, the dead time ranges for zero‐voltage switching of the converter are derived based on the improved time‐domain method. Experiments were carried out with a 10 kW LLC resonant converter. The lower limit of the dead time calculated with the proposed method is closer to the experimental results than the values of two conventional methods. [ABSTRACT FROM AUTHOR]

Retransmission in optical burst switching networks is a solution to recover data loss by retransmitting the dropped burst. The ingress node temporarily stores a copy of the complete burst and sends it each time it receives a retransmission request from the core node. Some retransmission schemes have been suggested, but uncontrolled retransmission often increases the network load, consumes more bandwidth, and consequently, increases the probability of contention. Controlled retransmission is therefore essential. This paper proposes a new controlled retransmission scheme for loss recovery, where the available bandwidth of wavelength channels and the burst lifetime are referred to as network conditions to determine whether to transmit a dropped burst. A retrial queue‐based analysis model is also constructed to validate the proposed retransmission scheme. The simulation and analysis results show that the controlled retransmission scheme is more efficient than the previously suggested schemes regarding byte loss probability, successful retransmission rate, and network throughput. [ABSTRACT FROM AUTHOR]

This paper presents an analytical modelling technique based on modified winding function and co‐energy analysis, for characterisation of synchronous reluctance machines, in conjunction with a hybrid algorithm for mapping of the machine's operating point on BH curve and the corresponding performance parameters in non‐linear magnetic condition. The model successfully provides the mean torque and the torque profiles of a synchronous reluctance motor as a function of input current and load‐angle in the magnetic linear and non‐linear conditions. The obtained results of this proposed model are compared with finite‐element‐analysis (FEA) based commercial design software Simcentre‐MAGNET. The comparison proves this model's capability to estimate the machine's performance parameters with considerable accuracy from an already established design analysis technique, FEA. The proposed modelling technique requires only a fraction of simulation runtime when compared to other design analysis techniques. Considering the accuracy of this modelling technique and the least requirement of computation resources and simulation time, this model can be used as an initial iterative‐design tool for mass personalised, additively manufactured electrical machines where rapidness of the iterative design analysis tool is of paramount importance. [ABSTRACT FROM AUTHOR]

In this paper a systematic procedure is developed to determine necessary conditions for all degrees of stochastic dominance. The previously known necessary conditions are specified as to which degrees of dominance they belong, and two new necessary conditions, a ranking of harmonic means and a ranking of algebraic combinations of the first three moments, are derived. [ABSTRACT FROM AUTHOR]

For homothetic time and state separable preferences, the coefficient of relative risk aversion (CRRA) is equal to the reciprocal of the elasticity of intertemporal substitution (EIS). This paper shows that when the growth rate of consumption is i.i.d., asset pricing models based upon preferences in which the CHRA and the EIS are no longer linked do not have more explanatory power. Further, in these stochastic environments, estimates of the CHRA in the standard preferences are measures of the true CHRA and not the EIS. These results are fairly accurate descriptions of economies calibrated using United States annual data. [ABSTRACT FROM AUTHOR]

This paper presents a diagnostic method of inverter open‐switch and open‐phase faults in multiphase permanent magnet synchronous motor (PMSM) drives. First defined are adequate variables called virtual current vectors. The projection of the zero‐sequence current component on these variables was used to define two simple fault indices. High sensitivity to fault is thus induced but with a good robustness to transient states and variation of machine parameters. The mathematical development of the proposed method is provided and supported by experimental tests conducted on two prototypes of multiphase machines in the laboratory: sinusoidal and bi‐harmonic PMSMs. The experimental results confirm the effectiveness and the robustness of the proposed method and its capability to detect the single and multiple open‐switches and open‐phase faults in the electric drive. [ABSTRACT FROM AUTHOR]

The invention of doubly‐fed induction generator (DFIG) brings the wind energy one step ahead as renewable power generation. But the performance of the grid‐connected DFIGs are greatly affected by grid disturbances as their stator windings are interfaced to the grid directly. Different fault current limiters are capable of improving fault ride through capability during short circuit faults. Nonlinear controller based fault current limiters (FCLs) are superior to deal with the nonlinearity of the power systems. This paper proposes a nonlinear adaptive backstepping controller (ABSC) based capacitive bridge‐type FCL (CBFCL) to enhance the fault ride through capability of a DFIG‐based wind farm connected to a multi‐machine power system. At first, a complete modelling of the CBFCL is derived to understand its behaviour during the normal and fault period more accurately. Then, the ABSC is designed based on that dynamic model, along with the backstepping controller (BSC) and sliding mode controller (SMC) for comparison purpose. Finally, the performance of the ABSC to control the CBFCL has been analysed and verified by comparing with that of the BSC and the sliding mode controller. All the graphical and mathematical analyses favour the ABSC based CBFCL under symmetrical and asymmetrical fault (both temporary and permanent) scenarios. [ABSTRACT FROM AUTHOR]

Integration of doubly‐fed induction generator (DFIG) based wind turbines (WTs), in series‐compensated power grids, may result in a phenomenon known as sub‐synchronous control interaction (SSCI). Indeed, SSCI, created due to interaction between WTs controllers and series‐compensated power grid, may worsen damping of sub‐synchronous resonance (SSR) oscillations. This paper deals with the analytical assessment and mitigation of SSCI phenomenon in series compensated grids comprising of DFIG‐based WTs. In this way, first, theoretical and mathematical expressions and equivalent circuits regarding the SSCI phenomenon and the impacts of the RSC and GSC controls on the SSR oscillations damping are given and then a comprehensive impedance model for the DFIG‐WT at the sub‐synchronous frequency is extracted. Next, the rotor current control is modified, and an efficient approach based on the feedback linearizing technique (FLT), different from approaches presented in the related literature, is presented to mitigate the negative role of the DFIG in SSR frequencies. By mathematical analyses and developing related formula, it is shown that the proposed approach changes the impedance of the rotor circuit to infinity at the SSR frequency. This in turn results in suppression of the SSR oscillations initiated as a result of induction generator effect and SSCI phenomenon. [ABSTRACT FROM AUTHOR]

This paper proposes a new semi‐parametric identification and estimation approach to multinomial choice models in a panel data setting with individual fixed effects. Our approach is based on cyclic monotonicity, which is a defining convex‐analytic feature of the random utility framework underlying multinomial choice models. From the cyclic monotonicity property, we derive identifying inequalities without requiring any shape restrictions for the distribution of the random utility shocks. These inequalities point identify model parameters under straightforward assumptions on the covariates. We propose a consistent estimator based on these inequalities. [ABSTRACT FROM AUTHOR]

The most common disadvantages of loss of excitation (LOE) impedance relay are its improper operation in the conditions of power system disturbances (PSD) and its long operation time. In this regard, to solve the mentioned problems and as a result improve the accuracy and speed of detecting the LOE events, four key variables including active power (Psg), reactive power (Qsg), load angle (δsg), and terminal voltage (Vsg) are selected, on the basis of an in‐depth theoretical‐ and simulation studies. These variables have been implemented in a precise combinational logic. In the developed LOE detection logic of this paper, the dependent parameters of Vsg and Qsg as well as Psg and δsg parameters are examined simultaneously in an AND logic cluster. If both the defined combinations detect the occurrence of LOE, the generator trip command is issued. Otherwise, the normal operation of the under‐study machine will continue. The results of the performed simulations in MATLAB/Simulink environment (2017b) during the detailed scenarios of LOE and PSD events on the IEEE 39‐bus standard system confirm the efficiency of the outlined LOE protection model. Meanwhile, its superiority from the viewpoints of accuracy, swiftness, and simplicity and cost of implementation are comprehensively compared with the other schemes. [ABSTRACT FROM AUTHOR]

Grey wolf optimization (GWO) algorithm is a new emerging algorithm that is based on the social hierarchy of grey wolves as well as their hunting and cooperation strategies. Introduced in 2014, this algorithm has been used by a large number of researchers and designers, such that the number of citations to the original paper exceeded many other algorithms. In a recent study by Niu et al., one of the main drawbacks of this algorithm for optimizing real‐world problems was introduced. In summary, they showed that GWO's performance degrades as the optimal solution of the problem diverges from 0. In this paper, by introducing a straightforward modification to the original GWO algorithm, that is, neglecting its social hierarchy, the authors were able to largely eliminate this defect and open a new perspective for future use of this algorithm. The efficiency of the proposed method was validated by applying it to benchmark and real‐world engineering problems. [ABSTRACT FROM AUTHOR]

In this paper, the problem of opportunistic spectrum sharing for the next generation of wireless systems empowered by the cloud radio access network (C‐RAN) is studied. More precisely, low‐priority users employ cooperative spectrum sensing to detect a vacant portion of the spectrum that is not currently used by high‐priority users. The authors' aim is to maximize the overall throughput of the low‐priority users while guaranteeing the quality of service of the high‐priority users. This objective is attained by optimally adjusting spectrum sensing time, with respect to target probabilities of detection and false alarm, as well as dynamically allocating C‐RAN resources, that is, powers, sub‐carriers, remote radio heads, and base‐band units. To solve this problem, which is non‐convex and NP‐hard, a low‐complex iterative solution is proposed. Numerical results demonstrate the necessity of sensing time adjustment as well as effectiveness of the proposed solution. [ABSTRACT FROM AUTHOR]

This paper intends to design an integral backstepping Lyapunov redesign controller (IBLRC) for various uncertain strict‐feedback‐form nonlinear systems. The pros and cons of backstepping Lyapunov redesign resulted in the design idea. An integral term is incorporated in conventional backstepping with Lyapunov redesign to indirectly decrease chattering and steady‐state error of a reference signal tracking when unknown static parameters and matched and unmatched dynamic uncertainties exist. The closed‐loop system is mathematically confirmed as stable in a Lyapunov frame, and we ultimately reach uniformly semi‐global boundedness of all signals. Simulation results of the proposed IBLRC are juxtaposed with those of the classic backstepping with the Lyapunov redesign. The proposed IBLRC realizes excellent tracking and enhanced robust performance than the BLRC for time‐varying and step tracking references. [ABSTRACT FROM AUTHOR]

p53 network, which is responsible for DNA damage response of cells, exhibits three distinct qualitative behaviours; low state, oscillation and high state, which are associated with normal cell cycle progression, cell cycle arrest and apoptosis, respectively. The experimental studies demonstrate that these dynamics of p53 are due to the ATM and Wip1 interaction. This paper proposes a simple two‐dimensional canonical relaxation oscillator model based on the identified topological structure of ATM and Wip1 interaction underlying these qualitative behaviours of p53 network. The model includes only polynomial terms that have the interpretability of known ATM and Wip1 interaction. The introduced model is useful for understanding relaxation oscillations in gene regulatory networks. Through mathematical analysis, we investigate the roles of ATM and Wip1 in forming of these three essential behaviours, and show that ATM and Wip1 constitute the core mechanism of p53 dynamics. In agreement with biological findings, we show that Wip1 degradation term is a highly sensitive parameter, possibly related to mutations. By perturbing the corresponding parameters, our model characterizes some mutations such as ATM deficiency and Wip1 overexpression. Finally, we provide intervention strategies considering our observation that Wip1 seems to be an important target to conduct therapies for these mutations. [ABSTRACT FROM AUTHOR]

This study deals with the investigation of the magnitude-frequency responses of all-pole fractional order systems in the viewpoint of extrema existence in these responses. In this investigation, a sufficient algebraic condition, two necessary algebraic conditions, and a necessary and sufficient algebraic condition are obtained to guarantee the non-existence of extrema in the magnitude-frequency response of all-pole fractional order systems. Some examples are presented to show the effectiveness of the results of the paper. [ABSTRACT FROM AUTHOR]

Fairness of exchange is a significant property for secure online transactions, and a fair exchange scheme is a useful tool for ensuring the fairness of exchanges conducted over networks. In this paper, we propose an ID-based optimistic fair exchange scheme based on the RSA function, one which is designed by combining a wellknown RSA-based signature scheme and the (naive) RSA function. Note that the main contribution of this paper is to give the first provably secure ID-based fair exchange scheme based on the RSA function, whose security can be proved under fully formalized security models. Our scheme has the following additional strongpoints. The scheme is setup-free; hence, there is no registration step between a user and an arbitrator. Moreover, the proposed scheme is designed in an ID-based setting; thus, it is possible to eliminate the need for certificates and avoid some related problems. [ABSTRACT FROM AUTHOR]

Most real-world negotiation involves multiple interdependent issues, which makes an agent's utility functions nonlinear. Traditional negotiation mechanisms, which were designed for linear utilities, do not fare well in nonlinear contexts. One of the main challenges in developing effective nonlinear negotiation protocols is scalability; they cannot find a high-quality solution when there are many issues, due to computational intractability. One reasonable approach to reducing computational cost, while maintaining good quality outcomes, is to decompose the utility space into several largely independent subspaces. In this paper, we propose a method for decomposing a utility space based on every agent's utility space. In addition, the mediator finds the contracts in each group based on the votes from all agents, and combines the contract in each issue-group. This method allows good outcomes with greater scalability than the method without issue-grouping. We demonstrate that our protocol, based on issue-groups, has a higher optimality rate than previous efforts, and discuss the impact on the optimality of the negotiation outcomes. [ABSTRACT FROM AUTHOR]

This paper introduces a new equation for modelling the phase noise spectrum of an oscillator. The new equation can model both of 1/f2 and 1/f3 regions in a phase noise spectrum. To verify the model and show its effectiveness, a mathematical analysis is performed on the effect of the oscillator phase noise on the performance of a continuous‐time delta‐sigma modulator. By comparing the results from the mathematical analysis with those from the Simulink simulation results, it is shown that using the proposed equation can properly predict the effect of oscillator phase noise on the modulator performance. [ABSTRACT FROM AUTHOR]

This paper proposes a load control module based on the consumers' vulnerability indices to improve the ability of radial microgrid (MG) to deal with line contingencies. This consumer switching module (CSM) increases the operational flexibility and is suitable for the radial MGs, where, a sudden line outage restricts access to the energy resources and deviates the system frequency in the created island. To cope with this condition, CSM can instantly disconnect some of the loads and reconnects them in an appropriate time sequence, considering loads' vulnerabilities. To include the CSM in the short‐term operation of MG, with the lowest complexity, a simple four‐stage structure is used. At first, the capability of CSM is determined in different islands related to potential line events. Then, the approximate cost function of CSM is applied to the short‐term MG operation which is hour‐ahead scheduling (HAS) including both the normal and the contingency state operation. Eventually, the determined optimal CSM participation level in each island is allocated to the consumers based on their exact offered price to calculate the load switching sequence. To evaluate the performance of the proposed scheduling manner, the 13‐bus and 123‐bus IEEE test systems are precisely analyzed considering different simulation scenarios. [ABSTRACT FROM AUTHOR]

This paper presents a new mathematical approach to design an asynchronous pulse width modulation (APWM) for the switched mode power supply (SMPS). Unlike the conventional APWM that utilises a Hysteretic comparator based Asynchronous Pulse Width Modulation (HAPWM) to provide the self-oscillating property, the proposed APWM is based on a Binary comparator based Asynchronous Pulse Width Modulation (BAPWM) and a delay cell. This way, compared to the HAPWM, the mathematical analysis of the modulator is significantly simplified. This was achieved by replacing the describing function (DF) -based graphical method with a -linearised mathematical model. The introduced mathematical approach is extended to study the behaviour of the higher order self-oscillating modulators in terms of the harmonic distortion. To confirm the effectiveness of the analytical derivations, the BAPWMs are employed in a classic DC-DC buck converter and the system-level simulation results are provided. It is concluded that there is an acceptable degree of similarity between the simulation results and the deployed analytical calculations for different orders of the modulators. Finally, to validate these analytical and simulation results and also to compare the BAPWM performance with its HAPWM counterpart, both modulators are implemented using off-the-shelf components and their measurement results are presented. [ABSTRACT FROM AUTHOR]

In this paper, a novel multi‐hop hybrid Free Space Optical (FSO)/RF link is presented; it is made up of two main parts. The first part establishes the connection between the mobile user and source base station, and the second part establishes the connection between the source and the destination base stations. In the first part, a mobile user wants to connect to the source base station via a long range link; therefore, a fixed gain amplify and forward relay with multiple receive antennas is used for communication establishment. In the second part, the source and the destination base stations are connected via a multi‐hop hybrid parallel FSO/RF link with demodulate and forward relaying. Considering the FSO link in Gamma‐Gamma atmospheric turbulence with the effect of pointing error in moderate to strong regime and the Negative Exponential atmospheric turbulence in saturate regime, and the RF link in Rayleigh fading, new closed form exact and asymptotic expressions are derived for the Outage Probability and Bit Error Rate of the proposed structure. [ABSTRACT FROM AUTHOR]

This paper examines some of the recent literature on the estimation of production functions. We focus on techniques suggested in two recent papers, Olley and Pakes (1996) and Levinsohn and Petrin (2003). While there are some solid and intuitive identification ideas in these papers, we argue that the techniques can suffer from functional dependence problems. We suggest an alternative approach that is based on the ideas in these papers, but does not suffer from the functional dependence problems and produces consistent estimates under alternative data generating processes for which the original procedures do not. [ABSTRACT FROM AUTHOR]

This paper considers assumptions on consumer heterogeneity that can generate bidirectional distortion in a model of quality discrimination. It is shown that the profit maximizing strategy can involve the simultaneous degradation of quality at the low end of the spectrum, while quality enhancement occurs at the high end. The implications of this result for optimal income taxes and incentive regulation are drawn out It is argued that the welfare losses of quality distortion are likely to be lower under bidirectional distortion than under the unidirectional distortion derived in the literature. [ABSTRACT FROM AUTHOR]

In this paper, five alternative advertising policies that belong to the advertising pulsation class are compared analytically for linear and concave response functions using a modified version of the Vidale-Wolfe model. The results of the research show that (1) For both linear and concave response functions, advertising pulsing/maintenance policy dominates advertising pulsing policy but is dominated by the Uniform Advertising Policy. For convex response functions, the order of dominance is reversed. (2) For linear response functions, uniform advertising policy dominates the impulse advertising policy but is dominated by the chattering advertising policy. (3) For concave response functions, uniform advertising policy dominates both the impulse advertising policy and the chattering advertising policy. (4) For convex response functions, chattering advertising policy dominates both the advertising pulsing policy and the impulse advertising policy. The Vidal-Wolfe model is estimated using the well-known Lydia Pink data. Optimality analysis shows that the company was over advertising about half of the time studied. Over advertising seems to have produced appreciable gain in sales and created significant harriers to competitive entry at a little cost in terms of foregone profits. [ABSTRACT FROM AUTHOR]

The paper explores, under a wide variety of circumstances, the welfare impact of emigration. The analytical framework posited is a simple two-factor, two-commodity, two-class general equilibrium model that makes a distinction between traded and non-traded goods. The principal aim is to collect and synthesize the well- known results in the literature, derived from diverse analytical frameworks, as well as to establish a number of new ones. It is shown that pure emigration can be beneficial to the non-emigrants in the source country, irrespective of the welfare criteria adopted, if accompanied by sufficient remittances. The paper also highlights the fact that emigation does not affect all classes in society symmetrically. The division of losers and gainers depends on the volume of remittances, the distribution of factor endowments and the type of emigration. [ABSTRACT FROM AUTHOR]

This paper develops a new field weakening method for an integrated permanent magnet synchronous machine vehicle drive. This method adopts both the DC-link and the rotor speed as a feedback signals to generate the demagnetising current reference. This eliminates the effect of the rotor speed on the FW controller dynamics and ensures stable operation across the whole range of speeds. Mathematical analysis of the system is used to design the controller gains to achieve the desired dynamic response. A maximum torque per ampere (MTPA) strategy is included in the control design, with a linearised function to reduce the computational demand. Experimental results show stable and satisfactory operation at different speeds and load conditions. They also illustrate smooth transition between the MTPA operation and the FW operation when the rotor speed crosses base speed. [ABSTRACT FROM AUTHOR]

This paper extends Milgrom and Robert's treatment of supermodular games in two ways. It points out that their main characterization result holds under a weaker assumption. It refines the arguments to provide bounds on the set of strategies that survive iterated deletion of weakly dominated strategies. I derive the bounds by iterating the best‐response correspondence. I give conditions under which they are independent of the order of deletion of dominated strategies. The results have implications for equilibrium selection and dynamic stability in games. [ABSTRACT FROM AUTHOR]

The article reports on the discussion of the study concerning the learning of mathematics. The discussion contains arguments regarding the paper written by professor Stone about functions. One of the arguments that is given attention to, is the concept of function being connected with the primitive concepts of pure logic, nearly unanalyzable and must be grasped by a psychological act of direct perception. This argument is also related to the child's development as the notion of grasping and perception are described to occur at some point in the development.

Energy efficiency (EE) is considered as one of the pivotal uplink (UL) performance metrics for 5G dense networks. It consists of two conflicting objectives that are recognised as benefit–cost ratio: spectral efficiency and energy consumption. Accordingly, network design tradeoff is the key challenge for future networks. In this paper, we aim to jointly maximise network spectral efficiency and minimise power consumption with respect to the following design parameters: base station (BS) density, users' number, equipped antennas' number, and signal‐to‐noise power ratio without losing service quality. The performance of the ultra‐dense network is characterised on the basis of the Pareto optimality concept through the following benchmarks: (i) studying impact of exhausted power on the deployed hardware elements. (ii) Validating the total EE performance through Monte‐Carlo simulation within a low cost of processing time. (iii) The proposed approach is compared against single objective scheme to show the significance of the design tradeoff. Furthermore, we will introduce a detailed mathematical analysis for UL power policy and channel estimation for reliable pilot reusing. Simulation results will show that our proposed solution guarantee remarkable EE performance via reducing the number of deployed BSs without scarificing service quality. [ABSTRACT FROM AUTHOR]

In this paper we examine optimal sample sizes using a formal Bayesian decision-theoretic approach, in which auditors seek to maximize expected utility subject to a budgetary constraint. The results are presented for finite and infinite population models based on a linear loss function and the prior distribution mean error rates for audit populations taken from the GA study. As with GA, the sampling designs are for compliance tests. Our results indicate that the formal Bayesian approach can provide optimal sample sizes which differ from those found using the informal approach, and that the optimal sample sizes may be larger for the finite model. [ABSTRACT FROM AUTHOR]

Conjugate duality relationships are pervasive in matching and implementation problems and provide much of the structure essential for characterizing stable matches and implementable allocations in models with quasilinear (or transferable) utility. In the absence of quasilinearity, a more abstract duality relationship, known as a Galois connection, takes the role of (generalized) conjugate duality. While weaker, this duality relationship still induces substantial structure. We show that this structure can be used to extend existing results for, and gain new insights into, adverse‐selection principal‐agent problems and two‐sided matching problems without quasilinearity. [ABSTRACT FROM AUTHOR]

There is an increase in renewable energy sources, which are regarded as current sources, where DC‐DC converters are widely used which require more suitable loads for driving current type loads. This paper uses a duality approach to show that the converter circuit can apply to the current type loads without too much voltage variation. It illustrates the derived steps for a conventional buck converter by using graph formation. To validate the duality approach, five original switching converters are detailed. A current source with an R‐L load (CSRL) converter is used for current‐based applications, such as electrical motors, electromagnetic relays, or light‐emitting diodes (LEDs). This study proposes a two‐phase non‐inverting buck‐boost converter with an R‐L load which is suitable for driving current‐based applications. The design procedure and steady‐state analysis are presented. SIMPLISTM software is used to simulate the topologies. This method for operation mode and formula derivation is like in voltage type circuit structures, and this study has sufficient mathematical analysis capabilities. For demonstration, a 650 W VSRL converter is implemented to verify the feasibility of the method. The corresponding circuit topology of the conventional circuit can be illustrated by using the duality approach rapidly. [ABSTRACT FROM AUTHOR]

A mathematical model is presented for the optimisation of an Electromagnetic Halbach Array (EHA) for wireless power transfer. The mathematical model is based on Biot‐Savart's law of magnetic field in a current‐carrying square loop. The model is validated through static electromagnetic simulations in ANSYS Maxwell and found to be accurate and effective when predicting the magnetic field within the EHA box. To verify the analytical and simulation results, an EHA was fabricated, and experimental verification was carried out. The results show that the mathematical model can be widely used in the analysis and design optimisation of EHAs of any size and with diverse parameters in the case of single‐layer square spiral planar coils. [ABSTRACT FROM AUTHOR]

The voltage‐source virtual synchronous generator is a grid‐forming type power electronic control technology and is able to support converters that have the ability of inertial, primary frequency and voltage regulation. Firstly, the authors build the small‐signal model of the voltage‐source virtual synchronous generator and conventional converters, compare and analyse the characteristics of the high‐frequency resonance modes, the results show that the voltage‐source virtual synchronous generator has almost the same high‐frequency resonance characteristics as the conventional converter. Secondly, the different control parameters and power grid strength that affect the high‐frequency resonance characteristic are analysed with eigenvalue, and the mechanism of voltage‐source VSG that caused high‐frequency resonance is derived. The leading factor that causes high‐frequency resonance is power grid strengths, and the authors proposed introducing virtual impedance into the front‐end channel of the current inner loop control strategy to suppress resonance for the voltage‐source virtual synchronous generator based on the theoretical analysis with the small‐signal model and eigenvalue analysis. In addition, the electromagnetic transient simulation model and RT‐LAB controller‐in‐loop platform are built, and the simulation and experiment results indicate the effectiveness of the virtual impedance control strategy. [ABSTRACT FROM AUTHOR]

An approach is presented to employ two different types of converters in bridgeless configuration for supply side power factor enhancement of the system. The isolated single‐stage electric vehicle battery charger uses two different converters in a bridgeless configuration to extract the advantages of both converters for supply‐side power factor enhancement. For the negative and positive semi‐cycles of the supply voltage, the power factor‐enhanced asymmetrical alternating current–direct current converter utilises a fourth order single‐ended primary‐inductor converter and a second order buck‐boost converter, respectively. The use of single‐ended primary‐inductor converter and buck‐boost converter in bridgeless configuration reduces the net order of the system with respect to conventional bridgeless‐single‐ended primary‐inductor converter schemes. The buck‐boost converter also needs the supply‐side filter to eradicate the unwanted harmonics in the supply current which increases the order of the system. The usage of both converters presents many benefits like input inductance of the single‐ended primary‐inductor converter can be utilised as a filtering element with a capacitor for the buck‐boost converter. The anti‐parallel diode conduction operation of both switches facilitates the elimination of extra reverse feed diodes (generally used in bridgeless schemes). The single‐stage charger itself comes with the benefit of elimination of extra stages and thus the losses associated with it. The presented charger also witnesses the elimination of the rectifier due to usage of bridgeless configuration. The isolated single‐stage electric vehicle battery charger is also garnished with electrical isolation which adds to the safety standard of the system. To attain power factor enhancement, the asymmetrical alternating current–direct current converter functions in discontinuous current conduction mode in the present work. The elimination of extra‐stages (with respect to two stage charger), a filter, a rectifier, two extra reverse‐feeding diodes, one voltage sensor, one current sensor (with respect to continuous current conduction mode), and electrical isolation not only makes the system compact and safer but also makes the system cheaper. Elaborated mathematical modelling and stability analysis of the presented alternating current–direct current converter using a pole‐zero map and bode plot have been included in the article. The prototype and MATLAB/Simulink model of isolated single‐stage electric vehicle battery charger system with discontinuous current conduction mode control has been built and results of both prototype and MATLAB/Simulink are deployed to verify isolated single‐stage electric vehicle battery charger system's performance during dynamic and steady‐state conditions. [ABSTRACT FROM AUTHOR]

We revisit the work of Butler et al. (1998) who examine the effect of mathematical preparation on grades received in intermediate economic theory courses. Using a Bayesian approach under reasonably ‘diffuse’ priors, we are able to replicate their two-step point estimates almost exactly. We also introduce a new model specification that accounts for the censoring and discrete nature of the outcome variable (grade received). The results from this specification echo the conclusions of the original paper—the level of calculus attained plays an important role in explaining grades received in intermediate micro theory. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper we consider a firm that can produce standardized products (SP) or customized build-to-order products (BOP) with short life-cycles. We develop a stochastic dynamic programming model to study the effect of offering price incentives to those customers who are willing to commit themselves to purchasing the cheaper-to-Produce standardized product. The market's reaction to price incentives is captured by modeling the probabilistic behavior of two exclusive groups of customers who may be "price-sensitive" or "price-insensitive" and who are willing to commit themselves. We develop an analytic expression for the distribution of the demand for the BOP conditional on the actual number of committed demands for SP following the price- incentive announcement. We show that price incentives expand the total expected demand while reducing demand uncertainty and we present conditions under which it is optimal to offer a price incentive. Sequentially made price incentive and capacity decisions for the BOP that maximize expected profit are obtained by solving the dynamic programming problem. We provide a comparative statics analysis and examine the effect of varying parameter values on the optimal price-incentive discount rate. We also describe a numerical study and present a sensitivity analysis of the profit improvement obtained after offering price incentives. We show that for low purchase probability, large number of customers in the price-sensitive group and high profit margin price incentives can substantially improve the expected profit. [ABSTRACT FROM AUTHOR]

When the Hurst coefficient of a fractional Brownian motionis greater than 1/2 it is possible to define a stochastic integral with respect to, as the pathwise limit of Riemann sums, and thus to consider pathwise solutions to fractional diffusion equations. In this paper, we consider the vanishing drift case and assume that the solutionX t is parameterized byθ in a compact parameter spaceΘ. Our main interest is the estimation ofθ based on discrete time, but with very frequent observations. It is shown that the estimation problem in this context is locally asymptotically mixed normal. The asymptotic behaviour of a certain class of minimum contrast estimators is then studied and asymptotic efficiency is discussed. [ABSTRACT FROM AUTHOR]

Stochastic discount factor (SDF) processes in dynamic economies admit a permanent-transitory decomposition in which the permanent component characterizes pricing over long investment horizons. This paper introduces an empirical framework to analyze the permanent-transitory decomposition of SDF processes. Specifically, we show how to estimate nonparametrically the solution to the Perron-Frobenius eigenfunction problem of Hansen and Scheinkman, 2009. Our empirical framework allows researchers to (i) construct time series of the estimated permanent and transitory components and (ii) estimate the yield and the change of measure which characterize pricing over long investment horizons. We also introduce nonparametric estimators of the continuation value function in a class of models with recursive preferences by reinterpreting the value function recursion as a nonlinear Perron-Frobenius problem. We establish consistency and convergence rates of the eigenfunction estimators and asymptotic normality of the eigenvalue estimator and estimators of related functionals. As an application, we study an economy where the representative agent is endowed with recursive preferences, allowing for general (nonlinear) consumption and earnings growth dynamics. [ABSTRACT FROM AUTHOR]

This study presents a fuzzy‐based optimal energy management scheme for a grid‐tied hybrid generation system. The hybrid system under study includes a fuel cell, an electrolyser, and a hydrogen storage subsystem and is also capable of exchanging power with the local grid under hourly electricity pricing. The topic of energy management is presented in detail in the form of a non‐linear constrained optimisation problem. A comprehensive mathematical formulation is applied to build an accurate model. Due to the complexity and large‐scale nature of the problem, its algebraic model is given in general algebraic modelling system (GAMS). Having developed an off‐line optimiser through interfacing GAMS and MATLAB, the optimal energy management problem is solved under different load profiles and the results are utilised to train a Sugeno‐type fuzzy inference system that is responsible for real time energy management. The fine tuning of the fuzzy system parameters, mainly including the membership functions and the weighting coefficients, is made using subtractive data clustering. To verify the performance and validity of the proposed approach, the simulation results are presented and discussed in both off‐line and on‐line modes. [ABSTRACT FROM AUTHOR]

When analysing how individuals allocate resources, sexual display should be regarded as is any other life-history trait: patterns of allocation are expected to be individually optimised. It thus follows that the costs of sexual selection can not be studied by simply comparing unmanipulated individual effort and some measure of cost. This rather trivial consequence of life-history theory has received surprisingly little attention in studies of sexual selection despite the almostuniversal acceptance of the theory and the fact that several papers have addressed the question specifically in the context of sexual selection. We therefore again outline why sexual displays are expected to be optimised at the level of the individual and why individuals with high access to resources should generally display at higher levels than individuals short of resources. We use some recent findings fromstudies of birds and spiders particularly relevant to the above questions that illustrate these principles. The examples we present show that the cost of sexual selection could be mediated in many ways and we thus suggest that future studies should focus on such mechanisms. [ABSTRACT FROM AUTHOR]

This paper explores the correspondence between the parameters of an extinction model analysedoeby Lande, Foley and Middleton et al. and the parameters of the incidence function model of metapopulation dynamics. The parameters of the extinction model, the intrinsic rate of population increase (r), its variance (v) and the population ceiling (K), can be mapped to the parameters of the incidence function model describing the scaling of the probability of local extinction (E) with area (A), E = e/Ax, via the equations s = x and r = eDs / s, where s = 2r / v, D is population density and K = DA. Iexplore this correspondence with two empirical examples, a mainland-island metapopulation of the European common shrew (Sorex araneus) onislands in lakes and a classical metapopulation of the American pika(Ochotona princeps). The most robust result is the correspondence x = 2r / v, which value decreases with increasing strength of environmental stochasticity. Thus the impact of environmental stochasticity onpopulation dynamics can, in principle, be inferred from the pattern of habitat patch occupancy in a metapopulation. [ABSTRACT FROM AUTHOR]

This paper presents a practical method for determining the waiting time distribution of a single-stage queueing system for general distribution of inter-arrival/ service times. The method requires the matrix solution of Lindley's equation for waiting time distribution by treating time in discrete units. Some important characteristics of the method are: a) it is easily programmable; b) it has high accuracy; c) it has modest CPU time and storage requirements; and, d) it requires no mathematical functional form for inter-arrival/service time distributions. [ABSTRACT FROM AUTHOR]