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In this paper, we shall present an analytical solution for current density from a sharp tip in the tip-to-plate configuration, with an applied dc voltage bias, using the methods of variational calculus. We shall also show that when the radius of the tip tends to infinity, we get back the current density formula for the classical Child-Langmuir (CL) law for a flat surface. The local current density near the tip is found to be much higher than the current density in the classical CL configuration. The results seem to be in agreement with the recent numerical simulations of the current density near a sharp tip.

The work is aimed to the study of materials based on lead selenide PbSe obtained by chemical bath deposition from aqueous solutions. The layers are studied with atomic force microscopy (topography and local current-voltage characteristics) and Raman spectroscopy.

An efficient technique for improving the accuracy of the domain Green's function method (DGFM) for the analysis of large finite antenna arrays with strong mutual coupling, is presented. The technique employs rigorous method of moments (MoM) analysis on strongly-coupled local domains. All antenna elements outside a local neighbourhood are still handled according to the standard DGFM approximation. This allows for maintained accuracy in case of very high local current variations and strong mutual coupling scenarios. A further improvement is presented, in order for the technique to be accurate for antenna arrays containing passive elements. The method maintains the low memory consumption and amenability to parallelization of the standard DGFM, but with improved accuracy.

This paper describes a novel flexible prototype device capable of both RF and microwave delivery for coagulation and ablation. The concept offers additional freedom to tailor the ablation profile in addition to key multimodality benefits (adjustable profile, thermal management, local current path, larger ablation). Finite element analysis, the prototype device and ex-vivo testing is presented. Good agreement was achieved between simulated and ex-vivo ablation profiles along with successful validation of the antenna design capable of delivering both RF and microwave energy. To the best of the authors knowledge, this is the first ablation antenna structure reported that combines the delivery of RF and microwave energy to produce optimal ablation volumes.

This study focuses on the localized junction defects in standard P-silicon solar cell provoked by the potential induced degradation (PID) under laboratory condition. Different characterization tools such as electroluminescence (EL), thermo-imaging, current density mapping, light and dark I-V and transient absorption spectroscopy (TAS) were employed to investigate the degradation involving to PID. A correlation between localized junction defects, local current loss and leakage current has been found.

This work develops the implementation of a software application that allows the management of digital medical records of populations of children and youths who are under criminal processes. This application allows the registration of clinical, mental and family environmental events that occur during the stay of patients in this kind of health care institutions. Based on local current legislation and regulations, the implementation of this application increases the efficiency and effectiveness in the execution of administrative and medical procedures to improve people rights of access to health processes, dignified treatment, containment of the family environment, etc. The adoption and knowledge transferred of this information technology to doctors and nurses establish the first step in an accurate, complete and timely record of vital information for future analysis of population behavior and decision making.

A distributed stochastic approximation algorithm with expanding truncations (DSAAWET) is proposed to estimate the unknown parameter linearly appearing in the sensor networks. Each agent updates its local estimate by averaging its neighbors' estimates with weights and by processing its local current observation. The estimates are shown to converge to the true parameter with probability one. A numerical example is given to demonstrate the obtained theoretic result.

Cu2ZnSn(S, Se)4 (CZTSSe) is emerged as a promising material because of non-toxic, inexpensive and earth abundant more than Cu(In, Ga)Se2. The highest conversion efficiency of CZTSSe is 11.1 % at IBM based on hydrazine process [1]. We have achieved CZTSSe thin-film solar cell 8% conversion efficiency by sputtering process. CZTSSe thin-films show different efficiency depending on selenization process. Depending on the different selenization process, conversion efficiencies in each sample are definitely distinguished from 8.06 to 3.17%. We investigated local electrical properties on these samples. The local surface potential is also critically different, which is ~ 200 mV on 8.06% film and ~ 70 mV on 3.17% film. From these results, we can suggest that selenization process can affect to local electrical characteristic as well as improving solar cell performances.

For pt.I see IEEE Trans. Ind. Appl., vol.24, no.5, p.922-7 (1988). In part I the problem of calculating particle charging in electrostatic precipitators in a self-consistent manner was addressed. A general solution in the form of a charging diagram was presented, but the details of the calculation process were left for detailed computer models. Two major simplifications are made by the author. One affects the form of the particulate-space-charge calculation, and the other is an analytic approximation of the corona wire V-I curve. With these simplifications and a bounding condition on the local current density, the self-consistent charging becomes much more tractable. Charging calculations with dilute and concentrated particle streams are compared. >

This paper reports about a new device for safety test of disposable grounding plates for electrosurgery. Neutral electrodes (grounding plates, dispersive electrodes) must fulfill the requirements of the american AAMI HF-18 standard. Instead of measurements on human volunteers an electronic devive was built to simulate human skin. Its conductive surface is devided into a number of 1 cm2 pads for a seperately measurement of local current density and local temperature rise. A PC-AT is used as control device and for graphical evaluation of electrical and thermal characteristics of the electrode under test.