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  • Author: Ming Yang x
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This study aims to present a new approach to detecting high impedance faults (HIFs) in the distribution feeder. Discrete wavelet transformations (DWT) and neural networks (NN) have been widely applied in power system research. Consequently, this study developed a novel technique to discriminate effectively between the HIFs and the switch operations by combining DWT with NN. The proposed approach has three distinct features. First, the input signal of this algorithm is neutral line current, rather than the conventional currents based on three individual phases. Second, HIFs identification uses the details at levels 3, 4 and 5 and the approximations at level 5 of the neutral line current are utilized for. Third, the input signals of the three-phase voltages classify the faulty and healthy phases. The results of simulation and field staged fault clearly show that the proposed technique can accurately identify the HIFs in the distribution feeder.

This paper is concerned with the economic incentives of crime among agents within a private organization. Specifically, we present a contest model of a college basketball game to identify the winners, losers, and social welfare consequences of point-shaving corruption in men’s NCAA basketball as an example of participation in illicit activities. It is shown that, under reasonable conditions, such activities lower the level of social welfare derived from college basketball play by reducing aggregate efforts in a game and distorting relative efforts across teams. We then examine the economic incentives of a player to point-shave and discuss player-types that are at a relatively high risk of engaging in point-shaving corruption. Private and public mechanisms to minimize corruption are compared in terms of efficiency, and a differential “honesty premium” is derived and discussed as an efficient way for the NCAA to decrease the incidence of player corruption.

The intrinsic permittivity, not apparent permittivity, of semiconducting layers of high voltage cross-linked polyethylene (XLPE) cables imposes a significant influence on the design of partial discharge detecting sensors. It has extremely high permittivity, resulting in a dimensional effect, an embodiment of the difference between the intrinsic permittivity and apparent or measurable permittivity. To investigate this dimensional effect in semiconducting material, a mathematical model is set up in this paper for a capacitor with two rectangular-shaped electrodes in parallel, between which is inserted a semi-conducting sample. First, the expression of the electric field in the semiconducting material is worked out theoretically. Then, the measurable or apparent complex permittivity is expressed as a function of intrinsic permittivity, dimensions of the sample and frequency. Next, five blocks with different dimensions are introduced to study the dimensional effect. The numerical analysis demonstrates that above 10 MHz, samples with different dimensions result in different apparent permittivity or measurable permittivity if experiments are carried out for the samples with the assumed dimensions. This implies that dimensional effects should be considered when accurate intrinsic permittivity of the semiconducting materials is needed.

Abstract

This paper uses a contest approach to characterize a probabilistic, non-price contest between potential consumers of rent-controlled apartments. The model extends upon the rent control model of Glaeser and Luttmer (2003) as well as the rent-seeking contributions of Hurley (1998), Dixit (1987), and Hirshleifer (1989) to consider the roles of chance and endogenously-chosen efforts in the allocation of rent-controlled apartments. Nash equilibrium effort levels for each consumer-type imply that the effort-inducing cost of rent control is greater than the misallocative cost. Further, misallocative costs are lower under the effort contest interpretation than under random allocation, as high willingness to pay consumers allocates more effort. The relationship between effort contest and misallocation influences the policy’s overall social cost.