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91.
The IEEE 802.15.6 standard is a communication standard optimized for low-power and short-range in-body/on-body nodes to serve a variety of medical, consumer electronics and entertainment applications. Providing high mobility with guaranteed Quality of Service (QoS) to a WBAN user in heterogeneous wireless networks is a challenging task. A WBAN uses a Personal Digital Assistant (PDA) to gather data from body sensors and forwards it to a remote server through wide range wireless networks. In this paper, we present a coexistence study of WBAN with Wireless Local Area Networks (WLAN) and Wireless Wide Area Networks (WWANs). The main issue is interworking of WBAN in heterogenous wireless networks including seamless handover, QoS, emergency services, cooperation and security. We propose a Seamless Interworking Architecture (SIA) for WBAN in heterogenous wireless networks based on a cost function. The cost function is based on power consumption and data throughput costs. Our simulation results show that the proposed scheme outperforms typical approaches in terms of throughput, delay and packet loss rate.  相似文献   
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Surface water from Miri Lake and groundwater from around Kadugli (West-Central Sudan) obtained by means of hand-pumps was analysed for (238)U, (226)Ra, (222)Rn, and (232)Th activity concentrations. The surface water showed very low levels of radionuclide concentrations: <1.0-7.5, 8.5-16.5, <1.6, and <0.1-0.39mBqL(-1) for (238)U, (226)Ra, (222)Rn, and (232)Th, respectively. Groundwater revealed a significant amount of natural radioactivity (16.1-1720, 7.7-14.3, 3000-139,000, <0.1-39mBqL(-1)) respectively. The overall annual effective dose was below the WHO reference dose level of 0.1mSvyr(-1) except in one groundwater sample with an associated dose of 0.7mSvyr(-1).  相似文献   
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Renewed interest has been expressed by researchers in mixed-method assessment that employs both quantitative and qualitative techniques in an expansive style that utilizes a variety of tactics to address research questions. Participants consisted of Puerto Rican women with severe mental illness living in Cuyahoga County, Ohio. The women were shadowed over a 2-year period to observe and verify behaviors that were self-reported using standardized instruments in semi-structured interviews. Concurrent criterion-related validity was employed to determine the extent of the correlation between responses obtained from the two approaches. Forty-four percent of the women were diagnosed with major depression and the mean overall GAF score was 58.5 ± 14.5. A comparison of the data collected using the different methodologies revealed that inconsistent and contradictory responses are not uncommon. The mixed-method design provided a more complete way of obtaining HIV-risk behavior data. Researchers and clinicians could benefit from mixed methods research that can provide greater opportunities to obtain data of a sensitive nature.  相似文献   
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Bacteria comprise an important part of the aquatic microbial flora and perform myriad of ecological roles in aquatic ecosystems. Yet the bacteriological studies on aquatic ecosystems are scarce, especially in the Himalayan context. The main objective of present study was to assess the bacteriological composition of Manasbal lake, the deepest freshwater lake of Kashmir Himalayas, in relation to anthropogenic pressures. The authors measured abundance of the culturable bacteria in lake waters from March to December 2011 using culture based approaches. A total of 1391 different colonies of the identified bacterial strains were obtained from the lake waters with significant site specific variability. The data indicated that the colony number was highest for site II (surrounded by residential hamlets) followed by site I (an irrigational stream) and III (Central site) and lowest for site IV (Outlet). The strains were identified using the gram’s staining, motility test and biochemical tests. Data revealed a highest percentage occurrence of 14.67 % for Proteus II and lowest of 0.21 % for Shigella I. This study indicated the need for development of a feasible system with regular assessment of microbial population for ascertaining the proper microbial load in order to effectively combat the multiple dangers of anthropogenic pollution of the lake.  相似文献   
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Quality of Life Research - Health-related quality of life (HRQL) is increasingly recognized for its importance in health research. As there is increasing recognition of the inter-individual...  相似文献   
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