Two-dimensional resolution of minority carrier diffusion constants in different silicon materials

Hall measurements are a common method to determine the majority charge carrier diffusion constant. But the diffusion constant of the minority carriers D_n, the more interesting parameter in photovoltaics, is rather hard to detect. In this paper we introduce a method to determine D_n locally resolved and mapped in two dimensions. For that purpose the local diffusion length L_diff, which can be calculated from LBIC (laser beam induced current) measurements, has been combined with the local bulk lifetime τ_b received by μ-PCD (microwave-detected photo conductance decay) measurements. We evaluated the diffusion constants of the minority charge carriers D_n for different p-type silicon materials with a resolution of 100 μm. The measurements were carried out on solar cells before and after remote plasma hydrogen passivation in order to get an impression of the diffusion constant dependency on hydrogen incorporation.     

Comparison of minority carrier diffusion length measurements in silicon solar cells by the photo-induced open-circuit voltage decay (OCVD) with different excitation sources

The photoinduced open-circuit voltage decay technique was used to investigate the minority carrier lifetime in crystalline and polycrystalline silicon solar cells. This convenient investigation technique allows a fast determination of the diffusion length of minority carriers in semiconductor materials and is an important technique to predict the solar cell performance. The decay curves were obtained with different excitation sources, a xenon stroboscope lamp and a Nd:YAG laser, and the results were compared.     

汉至清代广西食盐运销与少数民族淡食问题研究

汉至清代广西所需食盐主要从广东及沿海地区运销.广西境内多山,食盐运输困难,加上少数民族自身的贫困,盐价高而销量有限,盐商因之视为畏途.官府的食盐销售也量少价高,而且存在销售地域上的不平衡性,导致汉至清代广西各少数民族长期淡食,只能寻找食盐替代品,包括沥灰水为盐、食用酸糟和牛酱、以辣椒代盐.但从总体上看,伴随王朝势力的深入和广西少数民族聚居区的内地化进程,官盐销量逐步增加,少数民族的食盐消费水平渐趋提高,在一定程度上改善了淡食的局面.     

Immigration and Construction: Analysis of the Impact of Immigration on Construction Project Costs

There are an estimated 11 million illegal immigrants currently residing in the United States. Of this population, research shows that approximately 19% work in the construction industry, comprising around 14% of all construction workforces. The main objectives of this research are to (1) to predict possible effects of immigration and immigration reform legislation on worker wages and (2) to assess the likely wage increase due to decreased supply of immigrant labor. In the Washington, D.C. metropolitan region, the construction workforces for low-skilled trades such as concrete, masonry, drywall, painting, flooring, and roofing are comprised of approximately 55% illegal immigrant. Based on four factors evaluated in this research (1) prevailing wage provision in legislation; (2) forced tax compliance of the workforce; (3) market correction from currently depressed wages due to immigrant penetration into the workforce; and (4) a labor shortage resulting from a depleted supply of immigrant labor, proposed legislation could increase the cost of trade labor up to almost 70% in the Washington, D.C. metropolitan area. Overall labor costs for projects could increase by almost 18%, and total project costs could rise almost 12% in the Washington, D.C. metropolitan region.     

"聚落"的营造--日本京都车站大厦公共空间设计与原广司的聚落研究

该文通过对京都车站大厦中公共空间设计手法的分析,讨论了设计者原广司实践其中的聚落研究理论。     

新乡南太行地区传统村落空间特征及环境适应性分析 #

以新乡南太行地区传统村落为研究对象,运用田野调查结合无人机航拍、文献查阅等方法,从整体视角对该地区村落空间的构成要素进行剖析,并探讨村落营建中的环境适应性。结果表明：1) 村落选址多位于山麓或谷地; 2) 根据村落位置及街巷形态,可分为之字型、叶脉型、网格型三种类型;3) 适应地形的山地建造方式有三种：层叠式、高台式、错层式;4) 整体村落环境呈现“林 - 宅 - 田 - 水”四素同构的村落垂直景观模式;5) 作为村落空间构成要素的“三生空间”相互关联,满足了人类的生存、安全、宜居需求。     

黔中安顺屯堡聚落水环境与水景观营建研究

水作为重要的自然环境要素,在屯 堡聚落的形成与发展过程中发挥 着十分重要 的作用。文章在系统调研的基础上,分析了 安顺屯堡聚落水环境与水景观营建的4个主 要方面：聚落选址山水相生,主要选址位于 河谷坝子与周边山体交接之处,形成“山— 水—田—林—村”的整体空间格局;因水兴 建重要的屯田安居设施,解决饮用水源、山 地稻耕农作以及污水收集处理问题;凭借河 流水体参与防御体系构建,利用山水之势抵 御外侵,并人工修筑水渠等方式加强聚落防 御性;理水成景,营造稻作农业湿地景观、水 口园林景观等特色山地水景观。     

Inside the spiral: Hostile media,minority perception,and willingness to speak out on a weblog

This study took a snapshot at the psychological process of spiral of silence in an online environment with South Korean college students as the study participants. In an experiment, a Weblog-embedded news article from a media source incongruent with one's political orientation, as opposed to the same article from a congruent media source, triggered hostile media perception, which in turn led to presumed influence of the online news article on others. The presumed influence on others became a basis for assessing the online climate of opinion and led people to view themselves as a minority against the online climate of opinion. The media source factor, in conjunction with user comments factor, also generated different levels of minority perception both online and in the general society. In contrast to the notion of spiral of silence, minority perception against the general society's climate of opinion increased rather than decreased willingness to speak out.     

论电子政务与民族地区政府职能转变

我国民族地区政府因为其职能和行政环境与其他地方政府相比具有明显的特殊性和复杂性，其自治政府职能的转变更需要电子政务的支持。本文主要阐述了民族地区政府职能转变的重点以及电子政务对政府职能转变的推动作用，给民族地区政府电子政务与职能转变建设提供参考。     

A new technique in hydro thermal interconnected automatic generation control system by using minority charge carrier inspired algorithm

This article deals with Automatic Generation Control (AGC) of a multi area interconnected hydro thermal system in different modes using intelligent integral and proportional-integral controllers and provides the comparative analysis of electrical and mechanical governors. Appropriate Generation Rate Constraints (GRC) has been considered for the hydro and thermal generation plants. These cumulated thermal areas are considered with reheat turbines. Performances of reheat turbine mechanical governor and hydro turbine electrical governor with its dynamic responses have been investigated. Further, selection of suitable integral and proportional-integral controllers has been investigated with a Minority Charge carrier Inspired Algorithm (MCI). Cumulative system performance is examined considering with different load perturbation in both cumulative thermal areas. Further, system is investigated with different frequency bias values and results are explored.