Runoff and infiltration characteristics of pavement structures--review of an extensive monitoring program.

The stormwater runoff and infiltration performance of permeable pavements has been systematically evaluated within an intensive monitoring program. The primary objective of the investigation was to generate a broad database, which enables the development of an advanced simulation module for urban drainage modelling. Over 160 field and lab scale experiments have been completed and analyzed for surface runoff and infiltration characteristics. The test series include several pavement types under various boundary conditions such as diverse precipitation impacts, varying surface slope and layer construction as well as different stages of surface clogging and several base and subgrade layer characteristics. The results represent a reliable and comprehensive database that allows profound conclusions and substantial recommendations.     

我的九条命

在我生命中各个阶段里，我与学术界不知不觉地频频有缘。启蒙时期，我科到名师的熏导业已浸淫于国学；经史子籍，无所不读，撰文作诗，直追唐宋，俨然是一个“小老学究”。当我入仕时，一秉传统士大夫的志趋，一心为国为民，在我自我流放期间，发现我唯一可谋生的本领是学术，我既没有继承万贯家财，也没有在当权时放出许多人情，作为经商的捷径，实际上，我曾试探经商之路，但是在没有有力的后台引见下，我意识到，要加入一家企业，条件是能够为其带来多少商机，我对这种用才标准并不欣赏，在此情形下，要做一个小企业家，其生活方式也难以适应，特别是对我的妻女是一种冒险。     

Product Development Strategy and Organizational Learning: A Tale of Two PC Makers

The personal computer (PC) marketplace in the US presents a dizzying array of component suppliers and products. No single firm dominates the industry with a complete package of hardware and software components. Although one company's operating systems and general-purpose applications are installed on most PCs in the US, the other system components—processors, memory, storage devices, display adapters, monitors, specialized applications, and so on—come from any number of sources. David T. Methe, Ryoko Toyama, and Junichiro Miyabe point out that the PC industry in Japan also exhibits this decentralized nature. However, they also note that despite the decentralized network structure of the Japanese PC industry, one company—NEC—was able to achieve a dominant market share. To provide insight into the key issues involved in the management of complex technology, they contrast NEC's strategic approach to product development and organizational learning with the approaches taken by Fujitsu—the firm that placed a distant second in this market. Despite matching NEC in terms of technological capabilities, financial resources, and managerial talent, Fujitsu never managed to threaten NEC's dominance of the PC market in Japan. Fujitsu continually emphasized technological leadership, even at the expense of protecting its installed base. Poor coordination of resources and product development efforts resulted in incompatibilities among Fujitsu's various products, and the company failed to foster close relationships with suppliers of such key technologies as software and peripherals. NEC's PCs did not enjoy the advantages of first-to-market status or technological leadership. Instead, NEC achieved market dominance by finding the combination of product technologies that met the needs of the greatest number of consumers. Throughout almost 20 years of competition in the PC industry, NEC successfully maintained consistency and backward compatibility across its product lines. NEC also recognized the importance of third-party software developers, and carefully cultivated relations with these firms as a source of competitive advantage. In other words, NEC struck the right balance between three key factors: technological innovation, motivation of third-party developers of software and peripherals, and service to its installed base of customers.     

Experience with the antibiotic resistance analysis and DNA fingerprinting in tracking faecal pollution at two lake beaches.

Posting or closing of swimming beaches because of faecal contamination is a widespread problem reported in many locations. In a risk-based approach to this problem, the risk to swimmers' health is assessed by field monitoring of indicator bacteria and the associated risks are managed by source controls and other remedial measures. In risk assessment, great advances have been made in recent years with the introduction of microbial source tracking (MST) techniques. Two such techniques, antibiotic resistance analysis and DNA fingerprinting, were applied in a study of causes of faecal contamination at two lake beaches in Toronto, Ontario. Both methods identified bird faeces as the dominant sources of E. coli. Coping with this type of pollution presents a major environmental challenge.     

Effective lake basin management institutions: lessons from African lakes.

Weak or non-existent institutions are often cited as a major constraint facing management of many lake basins in Africa. By their nature lake basins cut across many sectoral and jurisdictional interests and therefore it is always the case that management of the basins is affected by actions within the various sectors and jurisdictions. Because of the complex nature of issues within lake basins, authority over management of lake basins is dispersed among several institutions, with no single institution having overall authority. Under these circumstances, a major challenge in lake basin management is how to ensure effective coordination among the various players. This paper reviews the situation of lake basin management at eight African lake basins and draws important lessons about lake basin management institutions. It is noted that fragmented approaches, lack of coordination across sectors, and lack of monitoring and enforcement are major institutional weaknesses. Also, it is observed that political will and commitment are essential for the management of African lake basins.     

Analysis of the Functioning of Automatic Synchronous Generator Excitation Regulators with Various Input Signals of Frequency Stabilization Channels in the Certification Scheme1

Power Technology and Engineering - Anecessary requirement for automatic excitation regulation systems is ensuring the stability of the electric energy systems (EES) and the required quality of the...     

On the variance of the ratio estimator

Summary In an earlier paper [Rao 1966] an exact expression for the variance of the ratio estimator under theMidzuno-Sen sampling scheme is obtained and here we study some of the interesting properties of the coefficients involved in this expression which depend on the auxiliary information. Use of these coefficients is made of in finding out an exact expression for the Bias and Mean Square Error of the ratio estimator under Simple Random Sampling With-Out Replacement (SRSWOR) scheme.