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The purpose of this study is to assemble information of costs per fatal casualty in traffic accidents, adopted by authorities in different countries. analyse and compare these figures as well as the methods used for estimating these values. A questionnaire was sent to 19 countries from which 11 gave information on cost per fatality and methods of valuation. The costs per fatality, usually defined as direct and indirect costs plus a value of safety per se, are compared both between countries and over time, 1990 and 1999, for each country. The average cost per fatality has increased between 1990 and 1999 (fixed prices) due to both changes in the methodology and changes of valuations. Great Britain, New Zealand, Sweden and the US conduct own willingness-to-pay (WTP) surveys, while the Netherlands and Norway make reviews of these studies. In Finland, the cost per fatality is a combination of the value of lost productivity and the cost of care for an institutionalised disabled person. In Australia, Austria, Germany and Switzerland, the cost per fatality is estimated as a value of lost productivity and an addition of a human cost based on compensation payments or insurance payments. Estimates from recently conducted WTP surveys or meta-analyses are considered in Austria, Finland and Sweden, however, not yet adopted as official values for use in road traffic planning.  相似文献   
3.
Brendan  C. Traw  S. 《Computer》2003,36(7):72-78
Ensuring viable economics for content providers and a compelling entertainment experience for consumers requires overcoming the technical challenges and limitations of content-protection mechanisms.  相似文献   
4.
A successful hardware/software architecture that resolves performance bottlenecks at the workstation-to-network host interface and offers high end-to-end performance is described. The solution reported carefully splits protocol processing functions into hardware and software implementations. The interface hardware is highly parallel and performs all per-cell functions with dedicated logic to maximize performance. Software provides support for the transfer of data between the interface and application memory, as well as the state management necessary for virtual circuit setup and maintenance. In addition, all higher-level protocol processing is implemented with host software. The prototype connects a RISC System/6000 to a SONET-based asynchronous transfer model (ATM) network carrying data at the OC-3c rate of 155 Mb/s. An experimental evaluation of the interface hardware and software has been performed. Several conclusions are drawn about this host interface architecture and the workstations to which it is connected  相似文献   
5.
Performance-based building regulation: current situation and future needs   总被引:1,自引:0,他引:1  
Although performance-based building regulations are in use or under development in numerous countries worldwide, there remain significant challenges in adequately identifying and defining performance, in understanding and addressing diverse societal expectations, and in establishing robust performance-based regulatory systems. These challenges become intensified as the building construction market becomes increasingly global, with the resulting expectation that building regulatory instruments remain valid across borders and do not create barriers to trade, while at the same time address local and national needs without compromising local cultural and societal norms. Many of these issues are just now beginning to be explored, and there is significant opportunity and need for future research and development in these areas.  相似文献   
6.
BACKGROUND: Intratracheal pulmonary ventilation (ITPV) is a form of tracheal gas insufflation in which all gas emerges in a cephalad direction from the tip of a reverse-thrust catheter positioned within an endotracheal tube. In vitro experiments have shown that this rapid gas flow, with 5 ml/h of normal saline added to the gas flow, continuously removes tracheal secretions from within the endotracheal tube. The authors evaluated its effectiveness to remove mucus in long-term studies in sheep. METHODS: Fourteen healthy sheep were tracheally intubated and ventilated for 3 days with ITPV or with volume-controlled ventilation. Measurements were made of the total amount of secretions within the endotracheal tubes (weight gain), the protein content within the endotracheal tubes, and the increase in resistance to constant air flow. The structure of the airways was examined grossly and histologically. Three additional sheep were ventilated for 24 h with ITPV, and Evans Blue dye was added to the saline to assess the distribution of the infused saline. RESULTS: There was significantly less mucus in endotracheal tubes of sheep ventilated with ITPV than with conventional ventilation, as shown by minimal weight gain (0.70 +/- 0.14 g vs. 2.44 +/- 0.81 g; P < 0.001), lower protein content (14.09 +/- 10.79 mg vs. 294.99 +/- 153.06 mg; P < 0.001), and lower resistance to constant air flow (6.15 +/- 0.54 cm H2O x 1(-1) x s(-1) vs. 15.34 +/- 5.28 cm H2O x 1(-1) x s(-1); P < 0.001). Results of gross and histological examinations of the tracheas of animals in both groups were similar, and the tracheas were well preserved. More than 95% of the instilled saline was recovered during ITPV. Only traces of Evans Blue dye were found near the tip of the endotracheal tubes. CONCLUSION: Intratracheal pulmonary ventilation makes it possible to keep the endotracheal tubes of sheep ventilated for 3 days free of mucus without suctioning.  相似文献   
7.
Learning from nature : In nature, riboflavin binding proteins are responsible for the transport and release of riboflavin. Here, the development of a molecular photorelease system based on the riboflavin binding protein dodecin is presented. Any drug or active chemical linked to a flavin can be captured by dodecin and transported to a location of interest. Irradiation with blue light results in the release of the ligands.

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8.
A survey for the presence of sequestered lichen compounds in 103 wild-caught imagines representing eight different genera and 16 different species of the Arctiidae was conducted. Known lichen compounds were detected for the first time in 24 of the analyzed specimens (representing five different genera and 11 different species) based on their HPLC retention times and on their UV-absorption spectra. The anthraquinone parietin, the depside atranorin, as well as a hydrolytic cleavage product of the latter were among the lichen compounds most frequently detected in wild-caught imagines. The observed variation of sequestered lichen compounds in wild-caught imagines with unknown feeding history may be due to several reasons. Lack of lichen compounds in imagines may have been caused, for example, by larvae feeding on lichens with no or only minute amounts of phenolic products. The age of the specimens analyzed may also influence the results obtained. Avoidance of lichen compounds by selective feeding on those parts of lichen thalli that have no or little lichen products may be another reason for the lack of lichen compounds in imagines. Preliminary feeding experiments conducted with larvae ofEilema complana, for example, indicated that the larvae fed exclusively on the algal layer and cortex of the lichenCladonia pyxidata, whereas the medulla, which is rich in fumarprotocetrarie acid, was avoided. As expected, imagines hatching from the larvae were free of this lichen compound. Any ecological role of the sequestered lichen compounds for the herbivores is unknown. It is possible, however, that sequestered lichen compounds may be utilized for the chemical defense of arctiid moths or against microbial pathogens.  相似文献   
9.
Smith  J.M. Traw  C.B.S. 《IEEE network》1993,7(4):44-52
Operating systems (OSs) used in high-speed networks must reduce copying to deliver maximal throughput to applications and must deliver this throughput while preserving the capability of the host to perform applications processing. One way to reduce copying by enabling data transfers directly to and from buffers located in application-process address spaces is presented. The method has been demonstrated experimentally and is shown to deliver high throughputs. OS support must also include scheduling, which allows bandwidth-allocated traffic streams to be delivered. The implementation described provides resource scheduling for network users, and considerably reduces interrupt overhead  相似文献   
10.
Traw  C.B.S. Smith  J.M. 《IEEE network》1995,9(4):22-32
Striping is a general architectural technique for the, transparent aggregation of multiple, functionally similar, resources to obtain higher performance. This article establishes a precise terminology for discussing striping and striping techniques, differentiates striping from the more general architectural technique of multiplexing, and outlines the major uses and trade-offs associated with the technique within the network subsystem. It presents a set of criteria for evaluating network striping and a case study of striping within a typical high performance network stack consisting of TCP/IP over ATM/SONET. IT also includes a set of “rules of thumb” for the inclusion of striping within the network subsystem. An appendix describes the trace driven simulation used to support the case study  相似文献   
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