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In this article, a new approach was established to estimate the fractional contributions of soil dust, biomass burning, biogenic emissions, coal burning, and vehicle exhaust to the carbonaceous particulate matter by carbon isotope and linear regression tech-niques of OC-K+ (organic carbon) and OC-EC (elemental carbon). Using the method described herein, the fractional distributions of these sources were quantitatively determined for the OC and semi-quantitatively for the EC in the size-resolved particles (size ranges: <0.49,0.49-0.95,0.95-1.5,1.5-3.0,3.0-7.2, and >7.2 /im) collected in Jiading District, a suburb of Shanghai, China. Distinct size dis-tribution of contributions of these sources to the OC and EC was observed. Generally, biomass burning contributed a large fraction to OC in the smaller particles and biogenic emissions shared a bigger fraction to OC in the larger particles. Soil dust made con-tributions solely to the OC, for no EC fraction was found in the soil dust. OC from coal burning concentrated in the fine particles (smaller than 3.0 /im), and that from vehicle exhaust exhibited bimodal distribution, with peaks for both fine and coarse parti-cles. The fossil sources dominated EC in almost all the size ranges. Though a few deviations are brought about in the calculation, this approach provides an effective way to distinguish the sources of the carbonaceous particulate matter. [ABSTRACT FROM AUTHOR]

Vehicle-based sensors can be used for traffic monitoring. These sensors are usually set with long sampling intervals to save communication costs and to avoid network congestion. In this paper, we are interested in understanding the traffic-monitoring performance that we can expect from such vehicle-based mobile sensor networks, despite the incomplete information provided. This is a fundamental problem to be addressed. A performance evaluation has been carried out in Shanghai, China, by utilizing the vehicle-based sensors installed in about 4000 taxies. Two types of traffic status-estimation algorithms, i.e., the link-based and the vehicle-based, are introduced and analyzed. The results show that estimations of the traffic status based on these imperfect data are reasonably accurate. Therefore, the feasibility of such an application is demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, we present the characteristics of a vehicular ad hoc network (VANET), which is the Shanghai urban vehicular network (SUVnet). We construct a mobility model using the GPS data collected from more than 4000 taxis in Shanghai. The model is both realistic and large scale. Based on this model, network topology and connectivity of SUVnet are studied. Because of the sparse distribution and dynamic topology of SUVnet, simply utilizing the conventional mobile ad hoc network routing protocols in SUVnet may not achieve a satisfactory performance. Therefore, we apply the delay-tolerant network model to SUVnet and evaluate the epidemic routing protocols. We propose a new protocol, which is the distance aware epidemic routing (DAER), to improve the bundle delivery ratio. Results show that DAER performs well for a VANET. This paper provides a basis in studying a realistic urban VANET. [ABSTRACT FROM AUTHOR]

In seeking to explain why Shanghai, China's economic capital, has a more timid media system than its sibling cities, we examine the political economy of the Shanghai media from the perspective of clientelism in the post-Communist and cultural milieus of what we call "party-market corporatism." Through field work we analyze four aspects of clientelism, including media conglomeration, elite circulation, resource allocation, and (lack of) media professionalism. We conclude that Shanghai is at once a "big city" and yet a "small place:" a resource-rich city governed by one layer of power authority, hence the distance from the epicenter of power to various media organizations is so short and direct as to make media control through clientelism very effective and powerful. Clientelism represents one of the three major patterns of party-market corporatism in China's media sector. [ABSTRACT FROM AUTHOR]