浅谈采用20kV作为配电电压的优越性

随着大城市中高层建筑群的崛起,以及工业技术开发区和大型住宅小区的形成,电力负荷剧增,负荷密度增大,传统的10kV配电方式已难以承受。介绍采用20kV配电的优越性。指出由10kV中性点不接地系统改为20kV中性点小电阻接地系统,应注意系统的绝缘水平、耐压,以及开关的开断性能等问题。     

Reply to Oosterhaven’s: the net multiplier is a new key sector indicator

This paper is a reply to Oosterhaven’s reply of the paper “A critical comment on Oosterhaven–Stelder net multipliers” written by de Mesnard in this issue of The Annals of Regional Science. It is argued that, unlike Oosterhaven’s statement, (1) any coefficient must be stable but Oosterhaven–Stelder final demand ratio is not; (2) the output must be exogenous in Oosterhaven–Stelder net multipliers (NM); (3) the Leontief input–output model can be validly seen as an iterative model, time consistent; (4) there is a valid link with the Keynesian multiplier; (5) the output preservation requirement is satisfied by de Mesnard’s ‘iterative net multiplier’. The paper concludes by agreeing to Oosterhaven’s suggestion that NM is not suitable to examine causalities between endogenous and exogenous variables and that the wording ‘multiplier’ is very bad and confusing for NM. Oosterhaven’s new suggestion of terming it as ‘net contribution’ or ‘net backward linkage’ is very good.     

The net multiplier is a new key sector indicator: reply to De Mesnard’s comment

Most of the comment of de Mesnard applies to a causal interpretation of the net multiplier that is applied to economically impossible exogenous (changes in) total output. This reply shows that this interpretation is incorrect and that his further argumentation is based on a time inconsistent derivation of the Leontief output multiplier. Instead the net multiplier concept is designed as a two-way dependency or net contribution indicator that—when applied to all sectors—reproduces the exact size of the economy at hand. De Mesnard’s iterative alternative does not satisfy this output preservation requirement and therefore it is not a proper net multiplier. Instead it equals an old gross multiplier, namely the one that indicates the indirect output effect per unit of final demand.     

Firm and household mobility in the presence of variations in regional characteristics

This paper examines the behavior of households and firms in the presence of variations in regional characteristics that affect their location decisions. It then determines relevant equilibrium conditions. Based on the implications of these equilibrium conditions, firm and household locations can be explained either by the dominance of firms or by the dominance of households. The results of this theory are applied to the case of 17 Arab countries. Received: November 1998/Accepted: June 2000     

用血量大于等于20 U患者围术期血液管理

目的　探讨手术相关用血量大于等于20 U患者围术期血液管理特点。方法　收集并分析北京协和医院2015年度用血量大于等于20 U手术患者的围术期资料，比较未经历非计划二次手术和经历非计划二次手术患者的相关信息。结果　共36例患者纳入研究，经历非计划二次手术患者（n=12）初次择期手术中失血量明显低于未经历非计划二次手术患者（n=24），分别为1300和3000 ml(P＜0.05)；但非计划二次手术相较于其初次择期手术美国麻醉医师协会（American Society of Anaesthesiology，ASA）分级明显增高，Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ级分别为0、0、4、8、0例和2、9、1、0、0例；术中出血量（分别为2250和1050 ml）和输血量（红细胞分别为8和1 U，血浆分别为400和100 ml）亦均明显增加（P均＜0.05）。36例患者中18例并发术前贫血。结论　对于手术难度大、风险高的患者，在充分评估术中出血风险的基础上，采取个体化治疗方案，纠正术前贫血，术中严密止血，加强围术期凝血功能检测，可降低非计划二次手术的发生率，改善患者结局。     

Economically valuing nature resources to promote conservation: An empirical application to Chile's national system of protected areas

Starting from the framework proposed by the Millennium Ecosystem Assessment (MEA) ? which conceptually links nature's services with human wellbeing ? we design and also apply empirically what we have called the total economic value calculating matrix (TEVCM) to estimate the monetary value of the annual flow of benefits provided by Chile's national system of protected areas (NSPA). The calculated economic value of this flow amounts to US$2.55 billion per year. We also analyse the relevance and usefulness of the methodology we propose and use the valuation exercise presented to extract some normative lessons regarding nature conservation in Chile as well as in developing countries rich in natural resource endowments.     

20kV供配电系统在民用建筑中的应用

以杭州奥体博览城主体育场区项目为例,介绍20kV供配电系统在民用建筑中的应用,以及在该项目设计过程中遇到的设计标准及产品支持等问题,总结20kV电压等级相对于10kV电压等级的优越性和应用前景。     

How can western China attract FDI? A case of Japanese investment

This paper adopts a conditional logit model to empirically examine the changes of Japanese investors’ location choices in response to China’s recent reorientation of its development strategy from the eastern coast to interior areas. This strategy adjustment is intended to attract FDI into China’s western region in hopes of promoting its economic growth and reducing economic inequality. Future policy suggestions on FDI attraction to western China are proposed based on the empirical details. This paper was the winning entry of the 19th Charles M. Tiebout Prize in Regional Science, and was presented at the 44th Annual Meeting of the Western Regional Science Association in San Diego, CA, February 2005.     

Regional disparities and determinants of growth in Mexico

Developing countries such as Mexico, in which profound processes of economic liberalization have taken place over the last few decades, offer fertile terrain for studies of regional disparities. Mexico has experienced a history of polarization between regions, the industrialized north and the underdeveloped south, which have seen their differences widen, exacerbated through recurrent crises and liberalization processes. This paper looks at the convergence process among regions, examining which factors might affect regional growth, tracking the evolution of single units and identifying winners and losers. The evidence shows that northern states, bordering the USA, moved from a condition that might be described as `falling-behind' prior to liberalization to that of a `winner' after that process, while southern states went from the position of `catching-up' to that of `loser'. Regional disparities in human capital would appear to be playing a decisive role in the existence of differences. The author acknowledges comments from Gilles Duranton, Henry Overman, Andrés Rodríguez-Pose, two anonymous referees, and participants in seminars in The London School of Economics and the European University Institute.     

荷兰建筑百年——本土都市主义

近年来，荷兰制造的建筑引起了全世界的关注。尤其是后OMA事务所的作品，被认为是一个荷兰的浪潮——甚至被称作超级荷兰实用主义。但是所谓“荷兰的”，究竟与地理位置之外的哪些因素相关？这个位于欧洲西北且仅有1600万人口的临海小国有什么奇异的魔力吗？或者说，正如风格派和结构主义时期，一种特定的时间地点的组合与更大范围内的国际潮流的碰撞。促成了对建筑的一种新的态度。以及一批拥护者？本文即是对现今的发展之前荷兰建筑界发生的事情的简要回顾。     

Nachträgliche Einwendungen; Rechtzeitigkeit

Eine Mauer an der Grundstücksgrenze, die diesen Teil des Grundstückes gegenüber dem Nachbargrundstück abschlie?t und keinen anderen Zweck (zB statischen Zweck im Hinblick auf das bestehende Geb?ude) erfüllt, ist als (hier: baubewilligungsfreie) Einfriedung zu qualifizieren.     

Spent nuclear fuel and residential property values: the influence of proximity, visual cues and public information

This article examines whether public knowledge of spent fuel storage at nuclear power plants, and any local adverse risk perceptions that may have occurred, affect the sale price of single-family residential properties. We present evidence from the Rancho Seco, California, plant on residential property values using an hedonic modeling framework. We include a large number of control variables, data with a high level of spatial detail and a number of public information variables in order to model property market effects within a fifteen mile radius of the plant. Our findings indicate that proximity and visual reminders of the plant have some influence on local property markets, and that there is a small media coverage effect on single-family home sale prices. Received: 6 May 1998 / Accepted: 26 May 1999     

浅谈20kV中压配电系统的应用

目前我国中压配电网基本以10kV为主。随着社会的发展，特别在经济发达地区，现有的10kV配电系统容量小、损耗大等问题日益突出，已经很难承受急剧增长的用电负荷。与传统的10kV配电网相比，20kV配电网具有节约投资、节约用地、节约能源、减少走廊等优点，不但可以增加供电能力，降低75％的电力损耗，还具有显著的环保效益。     

基于射频的数据采集与无线传输系统

介绍了一个基于射频技术的无线数据的采集传输系统,以射频技术为基础,对工业、工程现场的温度采集与传输的系统组成、硬件性能、软件设计进行了阐述,指出该系统实现了以无线方式对工业、工程现场的温度等数据进行采集、处理、传送、显示和上传的功能.     

The persistence of ecological-economic systems: Alternate measures and their properties

A number of ecologists and some economists have commented on the significance of persistence as a stability concept for jointly determined ecological-economic systems. This notwithstanding, the economics and the regional science literatures have paid scant attention to the problem of computing an ecological-economic system's persistence. As such, this paper has two objectives. First, we derive three measures of the persistence of a jointly determined ecological-economic system whose temporal behavior is governed by the presence of thresholds. Next, we compare and contrast these three measures. Finally, we discuss their theoretical properties and their practical uses. Received: March 2002/Accepted: September 2002 We thank T. John Kim and anonymous reviewers for their comments on a previous version of this paper. As well, we acknowledge financial support from the Gosnell endowment at RIT. This paper is dedicated to the memory of A.N. Batabyal (1937–2002). The usual disclaimer applies.     

Agglomeration and networks in spatial economics

Abstract. We consider the parallel developments in the economics of agglomeration and the economics of networks. We explore the complementarities between the productivity benefits of agglomeration and those of network linkages, arguing that networks of actors dispersed over space may substitute for agglomerations of actors at a single point.     

Photodegradation of CL-20: insights into the mechanisms of initial reactions and environmental fate

Hexanitrohexaazaisowurtzitane (HNIW) or CL-20 is a caged structure polycyclic nitramine that may replace RDX and HMX as a common use energetic chemical. To provide insight into the environmental fate of CL-20 we photolyzed the chemical in a Rayonet photoreactor (254-350 nm) and with sunlight in aqueous solutions. Previously, we found that initial photodenitration of the monocyclic nitramine RDX leads to ring cleavage and decomposition. Presently, we found that photolysis of the rigid molecule CL-20 produced NO2-, NO3-, NH3, HCOOH, N2 and N2O. Using LC/MS (ES-) we detected several key intermediates carrying important information on the initial steps involved in the degradation of CL-20. The identities of the intermediates were confirmed using a uniformly ring labeled 15N-[CL-20]. When CL-20 was photolyzed in the presence of H2(18)O, D2O or 18O2 we obtained a product distribution suggesting that the energetic chemical degraded via at least two initial routes; one involved sequential homolysis of N-NO2 bond(s) and another involved photorearrangement prior to hydrolytic ring cleavage and decomposition in water.     

Bewilligungspflicht; Anzeigepflicht; Verwendungszweckänderung

Bei einer Verwendungszweck?nderung sind auch damit untrennbar verbundene (und für sich alleine nur) anzeigepflichtige Ma?nahmen baubewilligungspflichtig.     

《百年西方城市规划理论史纲》导论

城市规划学界始终缺乏一个自己的基本理论平台。而规划学科一方面向社会、经济、生态领域扩展,另一方面内部的子学科又不断进行裂变,使得“规划的理论”的核心本身更显得“心虚”,“规划的理论”的概念和定义在讨论中愈加纷乱。本文从规划工作的核心出发．将规划的理论分成两大核心：规划目的和规划过程。通过对过去的１００年西方规划理论的发展走过的文脉,以求建构一个尽可能完整的城市规划理论的发展全过程的纲要。     

Production location choice and risk aversion

This paper attempts to provide a general comparative static analysis on a firm's choice of production location with respect to variations in the degree of risk aversion under demand price, input price, and technology uncertainties. Our analysis shows that whether and how the plant location varies with a change in the firm's degree of risk aversion depend upon the nature of the production technology and how the input and location choice affect risk. It also demonstrates that some of our results are new, while some are generalizations of those obtained by Martinich and Hurter (1982). Received: January 2000/Accepted: July 2000