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排序方式: 共有1172条查询结果,搜索用时 15 毫秒
1.
Paul Geoerg Florian Berchtold Steven Gwynne Karen Boyce Stefan Holl Anja Hofmann 《火与材料》2019,43(7):759-781
To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical‐, cognitive‐, or age‐related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design. 相似文献
2.
3.
Dr. Vlastimil Jirasko Dr. Nils-Alexander Lakomek Dr. Susanne Penzel Dr. Marie-Laure Fogeron Prof. Dr. Ralf Bartenschlager Prof. Dr. Beat H. Meier Dr. Anja Böckmann 《Chembiochem : a European journal of chemical biology》2020,21(10):1453-1460
Proton-detected 100 kHz magic-angle-spinning (MAS) solid-state NMR is an emerging analysis method for proteins with only hundreds of microgram quantities, and thus allows structural investigation of eukaryotic membrane proteins. This is the case for the cell-free synthesized hepatitis C virus (HCV) nonstructural membrane protein 4B (NS4B). We demonstrate NS4B sample optimization using fast reconstitution schemes that enable lipid-environment screening directly by NMR. 2D spectra and relaxation properties guide the choice of the best sample preparation to record 2D 1H-detected 1H,15N and 3D 1H,13C,15N correlation experiments with linewidths and sensitivity suitable to initiate sequential assignments. Amino-acid-selectively labeled NS4B can be readily obtained using cell-free synthesis, opening the door to combinatorial labeling approaches which should enable structural studies. 相似文献
4.
Semantic Web Mining: State of the art and future directions 总被引:2,自引:0,他引:2
Semantic Web Mining aims at combining the two fast-developing research areas Semantic Web and Web Mining. This survey analyzes the convergence of trends from both areas: More and more researchers are working on improving the results of Web Mining by exploiting semantic structures in the Web, and they make use of Web Mining techniques for building the Semantic Web. Last but not least, these techniques can be used for mining the Semantic Web itself.The Semantic Web is the second-generation WWW, enriched by machine-processable information which supports the user in his tasks. Given the enormous size even of today’s Web, it is impossible to manually enrich all of these resources. Therefore, automated schemes for learning the relevant information are increasingly being used. Web Mining aims at discovering insights about the meaning of Web resources and their usage. Given the primarily syntactical nature of the data being mined, the discovery of meaning is impossible based on these data only. Therefore, formalizations of the semantics of Web sites and navigation behavior are becoming more and more common. Furthermore, mining the Semantic Web itself is another upcoming application. We argue that the two areas Web Mining and Semantic Web need each other to fulfill their goals, but that the full potential of this convergence is not yet realized. This paper gives an overview of where the two areas meet today, and sketches ways of how a closer integration could be profitable. 相似文献
5.
Johanna Bakker Peter Bridle Anja Koopman 《Journal of the science of food and agriculture》1992,60(4):471-476
The colour stability of juice and purées made from a mixture of two strawberry varieties, stored at + 20°C or at –20°C under aerobic and anaerobic conditions, was studied. High-performance liquid chromatography and spectrophotometric analysis were used to monitor the changes in colour during storage. Pelargonidin 3-glucoside comprised 80% of the total anthocyanin content. Four other pelargonidin-based peaks were found, being 10.4%, 3.5%, 0.7% and 0.3% of the total and two cyanidin peaks were present, being 3.3% and 0.4% of the total. Clarification before storage caused considerable losses in the initial anthocyanin concentrations. Storage conditions (air versus nitrogen) did not influence the rate of loss of anthocyanins during storage or the formation of polymeric pigments. There were no losses in anthocyanins and no increase in the amount of colour measured at 510 nm due to polymers in samples stored at–20°C. Polymerisation occurred in the samples stored at + 20°C, especially in the clarified samples. 相似文献
6.
Bettina Berendt 《Data mining and knowledge discovery》2012,24(3):697-737
Over the last decade, privacy has been widely recognised as one of the major problems of data collections in general and the
Web in particular. This concerns specifically data arising from Web usage (such as querying or transacting) and social networking
(characterised by rich self-profiling including relational information) and the inferences drawn from them. The data mining
community has been very conscious of these issues and has addressed in particular the inference problems through various methods
for “privacy-preserving data mining” and “privacy-preserving data publishing”. However, it appears that these approaches by
themselves cannot effectively solve the privacy problems posed by mining. We argue that this is due to the underlying notions
of privacy and of data mining, both of which are too narrow. Drawing on notions of privacy not only as hiding, but as control
and negotiation, as well as on data mining not only as modelling, but as the whole cycle of knowledge discovery, we offer
an alternative view. This is intended to be a comprehensive view of the privacy challenges as well as solution approaches
along all phases of the knowledge discovery cycle. The paper thus combines a survey with an outline of an agenda for a comprehensive,
interdisciplinary view of Web mining and privacy. 相似文献
7.
Anja Oskamp 《Artificial Intelligence and Law》1992,1(4):245-274
This paper presents a four layer model for working with legal knowledge in expert systems. It distinguishes five sources of knowledge. Four contain basic legal knowledge found in published and unpublished sources. The fifth consists of legal metaknowledge. In the model the four basic legal knowledge sources are placed at the lowest level. The metaknowledge is placed at levels above the other four knowledge sources. The assumption is that the knowledge is represented only once. The use of metaknowledge at various levels should make it possible to use the appropriate knowledge for the problem presented to the system. The knowledge has to be represented as closely to the original format as possible for this purpose. Suitable representation formalisms for the various types of knowledge in the five knowledge sources are discussed. It is not possible to indicate a best representation formalism for each knowledge source. 相似文献
8.
Oliver Schmutzler Sebastian Graf Nils Behm Wael Y. Mansour Florian Blumendorf Theresa Staufer Christian Krnig Dina Salah Yanan Kang Jan N. Peters Yang Liu Neus Feliu Wolfgang J. Parak Anja Burkhardt Elisabetta Gargioni Sabrina Gennis Sharah Chandralingam Finn Heg Wolfgang Maison Kai Rothkamm Florian Schulz Florian Grüner 《International journal of molecular sciences》2021,22(7)
Quantitative cellular in vitro nanoparticle uptake measurements are possible with a large number of different techniques, however, all have their respective restrictions. Here, we demonstrate the application of synchrotron-based X-ray fluorescence imaging (XFI) on prostate tumor cells, which have internalized differently functionalized gold nanoparticles. Total nanoparticle uptake on the order of a few hundred picograms could be conveniently observed with microsamples consisting of only a few hundreds of cells. A comparison with mass spectroscopy quantification is provided, experimental results are both supported and sensitivity limits of this XFI approach extrapolated by Monte-Carlo simulations, yielding a minimum detectable nanoparticle mass of just 5 pg. This study demonstrates the high sensitivity level of XFI, allowing non-destructive uptake measurements with very small microsamples within just seconds of irradiation time. 相似文献
9.
Franziska Hornung Julia Rogal Peter Loskill Bettina Lffler Stefanie Deinhardt-Emmer 《International journal of molecular sciences》2021,22(7)
Obesity is a globally increasing health problem, entailing diverse comorbidities such as infectious diseases. An obese weight status has marked effects on lung function that can be attributed to mechanical dysfunctions. Moreover, the alterations of adipocyte-derived signal mediators strongly influence the regulation of inflammation, resulting in chronic low-grade inflammation. Our review summarizes the known effects regarding pulmonary bacterial and viral infections. For this, we discuss model systems that allow mechanistic investigation of the interplay between obesity and lung infections. Overall, obesity gives rise to a higher susceptibility to infectious pathogens, but the pathogenetic process is not clearly defined. Whereas, viral infections often show a more severe course in obese patients, the same patients seem to have a survival benefit during bacterial infections. In particular, we summarize the main mechanical impairments in the pulmonary tract caused by obesity. Moreover, we outline the main secretory changes within the expanded adipose tissue mass, resulting in chronic low-grade inflammation. Finally, we connect these altered host factors to the influence of obesity on the development of lung infection by summarizing observations from clinical and experimental data. 相似文献
10.
Suppression of the development of pores during laser-induced surface dispersion of TiC into aluminium, by means of a static magnetic field 总被引:1,自引:0,他引:1
A static magnetic field having the strength of B=0.6 T has been used as an additional process parameter in order to suppress the establishment of pores while dispersing TiC particles in surface layers of aluminium alloys using a laser. The migration of hydrogen towards regions of high temperatures within the melting pool can lead to the creation of gas bubbles, therefore yielding pores after resolidification in the processed layer. This mechanism (known for instance in welding technologies of aluminium) could be suppressed by Lorentz-forces induced by an externally applied magnetic field. It could be shown experimentally that magnetic fields could assist laser surface treatment processes beneficially if higher beam powers were coupled in. This may be interesting if, for instance, thicker dispersed layers should be achieved. 相似文献