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91.
Semantic web services are gaining more attention as an important element of the emerging semantic web. Therefore, testing semantic web services is becoming a key concern as an essential quality assurance measure. The objective of this systematic literature review is to summarize the current state of the art of functional testing of semantic web services by providing answers to a set of research questions. The review follows a predefined procedure that involves automatically searching 5 well-known digital libraries. After applying the selection criteria to the results, a total of 34 studies were identified as relevant. Required information was extracted from the studies and summarized. Our systematic literature review identified some approaches available for deriving test cases from the specifications of semantic web services. However, many of the approaches are either not validated or the validation done lacks credibility. We believe that a substantial amount of work remains to be done to improve the current state of research in the area of testing semantic web services.  相似文献   
92.
This work presents an analysis of the applicability of synthetic aperture radar (SAR) interferometry to landslide monitoring. This analysis was carried out by using different interferometric approaches, different spaceborne SAR data (both in the C-band and in the X-band), and in situ global navigation satellite system (GNSS) measurements. In particular, we investigated both the reliability of displacement monitoring and the issues of the cross-comparison and validation of the interferometric synthetic aperture radar (InSAR) results. The work was focused on the slow-moving landslide that affects a relevant part of the urban area of the historical town of Assisi (Italy).

A C-band ENVISAT advanced synthetic aperture radar (ENVISAT ASAR) dataset acquired between 2003 and 2010 was processed by using two different interferometric techniques, to allow cross-comparison of the obtained displacement maps. Good correspondence between the results was found, and a deeper analysis of the movement field was possible. Results were further compared to a set of GNSS measurements with a 7 year overlap with SAR data. A comparison was made for each GNSS marker with the surrounding SAR scatterers, trying to take into account local topological effects, when possible.

Further, the high-resolution X-band acquired on both ascending and descending tracks by the COSMO-SkyMed (CSK) constellation was processed. The resultant displacement fields show good agreement with C-band and GNSS measurements and a sensible increase in the density of measurements.  相似文献   
93.
In WiMAX systems the Base Station scheduler plays a key role as it controls the sharing of the radio resources among the users. The goal of the scheduler is multiple: achieve fair usage of the resources, satisfy the QoS requirements of the users, maximize goodput, and minimize power consumption, and at the same time ensuring feasible algorithm complexity and system scalability. Since most of these goals are contrasting, scheduler designers usually focus their attention on optimizing one aspect only. In this scenario, we propose a scheduling algorithm (called GTSN\mathrm{GTS_N}) whose goal is to contemporaneously achieve efficiency and fairness, while also taking into account the QoS requirements and the channel state. GTSN\mathrm{GTS_N} exploits the properties of Time Utility Functions (TUFs) and Game Theory. Simulations prove that the performance of GTSN,\mathrm{GTS_N}, when compared to that of several well-known schedulers, is remarkable. GTSN\mathrm{GTS_N} provides the best compromise between the two contrasting objectives of fairness and efficiency, while QoS requirements are in most cases guaranteed. However, the exponential complexity introduced by the game theory technique makes it rather impractical and not computationally scalable for a large number of users. Thus we developed a suboptimal version, named sub-GTSN.\mathrm{GTS_N}. We show that this version retains most of the features and performance figures of its brother, but its complexity is linear with the number of users.  相似文献   
94.
认为web3.0和社交网络会让我们摆脱在公共空间中进行物理交流需求的想法需要再斟酌。事实上,当环境中的技术设施让我们能够用负担得起的可移动设备与世界相联系、让新的工作和社交模式能够在家里甚至喜爱的酒吧中产生的时候,很多在家工作的人和网友开始感受到一种需要重新建立起某些真正的社会团体的需求。因此很容易理解,在过去的几十年中,许多城市成为一种"合作"机制网络成长的摇篮。"合作"机制是一种实验,为喜欢与他人共享空间的人们提供廉价、灵活和非正规的生活和工作的解决方案。更准确地说,分享是这些措施中可持续性的关键,因为仅仅通过让一个  相似文献   
95.
96.
The advantages and open questions of the combination of modulation excitation spectroscopy and phase sensitive detection (PSD) with X-ray absorption spectroscopy (XAS) for the analysis of heterogeneous catalysts at work are reviewed. The characteristic spectral signatures of two different edges (Pd K and Pt L3) are described in relation to the red-ox chemistry of Pd/Al2O3 and Pt/Al2O3 with respect to NO reduction by CO and CO oxidation, respectively. Both examples demonstrate that PSD makes XAS sensitive to potentially active species for the catalytic reaction.  相似文献   
97.
Chlorophenols are harmful pollutants, frequently found in the effluents of several industries. For this reason, many environmental friendly technologies are being explored for their removal from industrial wastewaters. The aim of the present work was to study the scale up of 2,4-dichlorophenol (2,4-DCP) removal from synthetic wastewater, using Brassica napus hairy roots and H2O2 in a discontinuous stirred tank reactor. We have analyzed some operational conditions, because the scale up of such process was poorly studied. High removal efficiencies were obtained (98%) in a short time (30 min). When roots were re-used for six consecutive cycles, 2,4-DCP removal efficiency decreased from 98 to 86%, in the last cycle. After the removal process, the solutions obtained from the reactor were assessed for their toxicity using an acute test with Lactuca sativa L. seeds. Results suggested that the treated solution was less toxic than the parent solution, because neither inhibition of lettuce germination nor effects in root and hypocotyl lengths were observed. Therefore, we provide evidence that Brassica napus hairy roots could be effectively used to detoxify solutions containing 2,4-DCP and they have considerable potential for a large scale removal of this pollutant. Thus, this study could help to design a method for continuous and safe treatment of effluents containing chlorophenols.  相似文献   
98.
99.
This paper describes the energy consumption performance of sea-going ships engaged in the EU27 seaborne trades based on data and parameters resulting from the EX-TREMIS (EXploring non road TRansport EMISsions in Europe) database. EX-TREMIS is a comprehensive database of fleet and transport activity data, specific energy consumption, emission factors and total emissions from rail, maritime and air transport in the European Union. The EX-TREMIS maritime model derives from a mixture of top–down and bottom–up approaches for estimating pollutant emissions from shipping activities. The model did not use direct observations of actual trips, but empirically derived the number of equivalent-ships. Cargo type shipments were linked to seven ship type categories for which a further segmentation by ship size (three length classes), type and age of the main engine and type of fuel was applied.  相似文献   
100.
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