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131.
Linked Data has become the current W3C recommended approach for publishing data on the World Wide Web as it is sharable, extensible, and easily re-usable. An ecosystem of linked data hubs in the Public Sector has the potential to offer significant benefits to its consumers (other public offices and ministries, as well as researchers, citizens and SMEs), such as increased accessibility and re-use value of their data through the use of web-scale identifiers and easy interlinking with datasets of other public data providers. The power and flexibility of the schema-defying Linked Data, however, is counterbalanced by inborn factors that diminish the potential for cost-effective and efficient adoption by the Public Sector. The paper analyzes these challenges in view of the current state-of-the-art in linked data technologies and proposes a technical framework that aims to hide the underlying complexity of linked data while maintaining and promoting the interlinking capabilities enabled by the Linked Data Paradigm. The paper presents the innovations behind our proposed solutions as well as their advantages, especially for the non-expert users.  相似文献   
132.
Nowadays, Internet users are depending on various search engines in order to be able to find requested information on the Web. Although most users feel that they are and remain anonymous when they place their search queries, reality proves otherwise. The increasing importance of search engines for the location of the desired information on the Internet usually leads to considerable inroads into the privacy of users. A heated debate is currently ongoing at European level regarding the question if search engine providers that are established outside the European Union are covered by the European data protection framework and the obligations it imposes on entities that process personal data. The scope of this paper is to examine the applicability of the European data protection legislation to non-EU-based search engine providers and to study the main privacy issues with regard to search engines, such as the character of search logs, their anonymisation and their retention period. Ixquick, a privacy-friendly meta-search engine, will be presented as an alternative to privacy intrusive existing practices of search engines.  相似文献   
133.
In this paper, we introduce the idea of documenting operational chains for land degradation assessment using ontologies. We believe that this process will help end users better understand the application domain characteristics and evaluate the results of the assessment process. Since the application domain is wide, various operational chains for land degradation assessment and their associated documentation exist, according to different options. This parameterization process causes the development of different ontologies, which nonetheless are, to a certain extent, linked because of the common software components of the corresponding operational chains. We therefore propose a hierarchical structure of these ontologies; so that several requirements such as understanding of expert knowledge interconnections and of application domain variety, documentation and assimilation of new expert knowledge, and reusability of software components become feasible.  相似文献   
134.
Electrospray ionization (ESI) is extensively used in the analysis of biological compounds; yet some fundamental properties of this technique are not completely understood. It is widely recognized that care should be exercised when noncovalent complexes are being studied by ESI, since weak noncovalent binding can be broken or formed during the desolvation process. In the present work, spectra from the noncovalent complex, vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine, obtained from ESI and from nanoelectrospray ionization (nanoESI), have been compared. The results indicated that the milder desolvation conditions arising as a result of the smaller sizes of droplets produced in the nanoESI source attenuated effects upon weak bonds in the desolvation process. The association constant values calculated from the relative peak intensities suggest that, when using ESI, the analyzed noncovalent complex dissociated in the condensed phase during the spraying process. The influences of experimental parameters such as tip diameter and coating for nanoESI needles were investigated. Principal component analysis, a multivariate analysis method, was applied to achieve a better evaluation of the spectra obtained using different needle diameters and coatings for the analysis of the noncovalent complex vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine. It was found that 2-microm tip diameter resulted in more reproducible spectra than the larger tip diameters tested (6-20 microm).  相似文献   
135.
The application of high intensity, low frequency ultrasound for the disinfection of simulated and septic tank wastewaters is evaluated in this work. Laboratory scale experiments were conducted at 24 and 80kHz ultrasound frequency with horn-type sonicators capable of operating in continuous and pulsed irradiation modes at nominal ultrasound intensities up to 450W. For the experiments with simulated wastewaters, Escherichia coli were used as biological indicator of disinfection efficiency, while for the experiments with septic tank wastewaters, the total microbiological load was used. Complete elimination of E. coli could be achieved within 20-30min of irradiation at 24kHz and 450W with the efficiency decreasing with decreasing intensity and frequency. Moreover, continuous irradiation was more effective than intermittent treatment based on a common energy input. Irradiation of the septic tank effluent prior to biological treatment at 24kHz and 450W for 30min resulted in a three-log total microbiological load reduction, and this was nearly equal to the reduction that could be achieved during biological treatment. Bacterial cell elimination upon irradiation was irreversible as no reappearance of the microorganisms occurred after 24h.  相似文献   
136.
Summary The computation of critical loads in problems of elastic buckling of bars and frames is generally reduced to the numerical solution of a transcendental equation. In this paper, we apply a new method, based on Gaussian quadrature rules, for the solution of transcendental equations to the determination of critical loads in buckling problems. Two such problems of practical interest are completely solved for the illustration of the method and numerical results are presented. The main advantages of the present method are its simplicity and the availability of closed-form formulae for the critical loads, from which the numerical results are obtained by using Gaussian quadrature rules. A comparison between the present method and the method of Burniston and Siewert is also made.With 2 Figures  相似文献   
137.
The Digital Imaging and Communications in Medicine (DICOM) protocol is currently the ubiquitous standard for the communication of medical images and related data within the radiology department. However, seamless image distribution within the healthcare enterprise and especially with research and educational information systems is still hard to achieve, as software developers of such third-party applications have to go through the rather cumbersome task of adapting the DICOM communication model and implementing the DICOM protocol. This paper gives a brief outline of current trends in medical image distribution in the healthcare enterprise, and proposes a new technological approach for distributing DICOM images and related data through commonplace Internet technologies, based on the emerging web services software paradigm. In particular, the paper describes the DICOM Image Management (DIM) web service which acts as a fa?ade for conventional DICOM sources allowing DICOM image data and related information, to be transformed into XML documents encapsulated in SOAP messages, enabling integration at the application level through general purpose standardized web technologies. Implementation issues are discussed and a demonstration of engaging the DIM web service is included.  相似文献   
138.
The extended finite element formulation (XFEM) combined with genetic algorithms (GAs) have previously been shown to be very effective in the detection of flaws in structures. By this approach, the XFEM is used to model the forward problem and a GA is used as the optimization scheme, converging to the true flaw. The convergence is obtained by minimizing the error between sensor measurements and data obtained by solving the forward problem.The current study proposes several advances of this XFEM–GA algorithm, more specifically: (i) a novel genetic algorithm that accelerates the convergence of the scheme and alleviates entrapment in local optima, (ii) a generic XFEM formulation of an elliptical hole which is utilized to detect any type of flaw (cracks or holes) of any shape, and (iii) experimental verification of the approach for an arbitrary crack in a 2D plate.Convergence studies on various benchmark problems including the experimental verification clearly show the potential of this approach to detection of arbitrary flaws.  相似文献   
139.
The issue-tracking systems used by software projects contain issues, bugs, or tickets written by a wide variety of bug reporters, with different levels of training and knowledge about the system under development. Typically, reporters lack the skills and/or time to search the issue-tracking system for similar issues already reported. As a result, many reports end up referring to the same issue, which effectively makes the bug-report triaging process time consuming and error prone. Many researchers have approached the bug-deduplication problem using off-the-shelf information-retrieval (IR) tools. In this work, we extend the state of the art by investigating how contextual information about software-quality attributes, software-architecture terms, and system-development topics can be exploited to improve bug deduplication. We demonstrate the effectiveness of our contextual bug-deduplication method at ranking duplicates on the bug repositories of the Android, Eclipse, Mozilla, and OpenOffice software systems. Based on this experience, we conclude that taking into account domain-specific context can improve IR methods for bug deduplication.  相似文献   
140.
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