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1.
Antibiotic and multi-drug resistant (MDR) Salmonella poses a significant threat to public health due to its ability to colonize animals (cold and warm-blooded) and contaminate freshwater supplies. Monitoring antibiotic resistant Salmonella is traditionally costly, involving the application of phenotypic and genotypic tests over several days. However, with the introduction of cheaper semi-automated devices in the last decade, strain detection and identification times have significantly fallen. This, in turn, has led to efficiently regulated food production systems and further reductions in food safety hazards. This review highlights current and emerging technologies used in the detection of antibiotic resistant and MDR Salmonella.  相似文献   
2.
Distributed computing for multidisciplinary design optimization using Java   总被引:1,自引:0,他引:1  
The programming language Java (recently referred to as the computer language of the Web) offers substantial possibilities for the type of complex engineering problems typically encountered in multidisciplinary design optimization (MDO) problems. In order to demonstrate the potential uses of Java for MDO problems, this paper presents the development of the Web Interface for complex engineering design (WICkED) software, which simulates the convergence of a decomposed complex system in a distributed computing environment and computes the sensitivity derivatives of the system with respect to the independent input variables using the GSE method or the finite difference method. In this application, one computer is designated as the server and sends out required inputs to a number of client subsystems over the Internet. A number of client computers can connect to the server and then receive the inputs necessary to calculate the solution to their model. As the code necessary to solve the model already exists at the client, only the inputs have to be sent over the network. When the client has solved the calculation, it returns the results to the server which processes the result to produce new inputs.WICkED is written entirely in the Java programming language which allows server and clients to exist on completely different computer types and in heterogeneous, distributed networks. A number of parametric studies on the behaviour of complex systems in a distributed environment are performed and the results are reported in this paper. This research serves to identify potential problems as well as advantages in using Java for MDO applications.  相似文献   
3.
Daily precipitation in the UK has changed over the period 1961-2000, becoming on average more intense in winter and less intense in summer. Recent increases in total winter precipitation are shown to be mainly due to an increase in the amount of precipitation on wet days, with a smaller contribution in the western UK from a trend towards more wet days. If the wet-day amounts are modelled using a gamma distribution, then positive trends in its scale parameter are found across almost all of the UK, consistent with an increased frequency of heavy winter precipitation. Non-parametric analyses confirm an increase in the contribution of heavy events to winter precipitation totals. Analysis of multi-day sequences of heavy rainfall indicate a corresponding increase in their frequency. Results for summer show almost opposite trends: decreased precipitation totals (driven more equally by fewer wet days and reduced wet-day amounts), decreases in gamma scale parameter (although accompanied by a trend towards a less positively skewed distribution) and decreases in the occurrence of heavy precipitation (whether defined parametrically or non-parametrically). A more sparse network of weather stations with data back to 1901 suggests that the recent winter changes are unusual, while the recent summer changes are not, though the poorer coverage reduces the confidence in these longer-period results.  相似文献   
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5.
Immediate memory span and maximal articulation rate were assessed for word sets differing in frequency, word-neighborhood size, and average word-neighborhood frequency. Memory span was greater for high- than low-frequency words, greater for words from large than small phonological neighborhoods, and greater for words from high- than low-frequency phonological neighborhoods. Maximal articulation rate was also facilitated by word frequency, phonological-neighborhood size, and neighborhood frequency. In a final study all 3 lexical variables were found to influence the recall outcome for individual words. These effects of phonological-word neighborhood on memory performance suggest that phonological information in long-term memory plays an active role in recall in short-term-memory tasks, and they present a challenge to current theories of short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The role of pharmacies that specialize in the treatment of specific chronic diseases in the alternate-site health care setting is discussed. The optimal use of medications through disease management programs can improve patient outcomes and lower overall health care costs. The increase in disease management programs has spawned the growth of disease-specific pharmacies in the home care and other alternate-site health care settings. These pharmacies usually operate from a single location or are regionalized operations that deliver pharmaceutical products to patients throughout the United States. The pharmacies employ clinicians who specialize in a particular disease. These clinicians conduct comprehensive patient education programs, drug-use review, and compliance monitoring. Disease management pharmacies focus on chronic, expensive diseases; costs related to inventory, equipment, and storage can be very high. Many disease management pharmacies are involved in preferred-distribution or closed-distribution arrangements with pharmaceutical manufacturers. Pharmacists involved in disease management programs routinely send compliance information about their patients to pharmaceutical companies, managed care organizations, or prescribing physicians. Disease management pharmacies act as advocates for patients with particular chronic diseases. Various foundations and patient advocacy and research groups have created their own disease management pharmacies. Disease management has also reached the community pharmacy practice setting. Pharmacies specializing in the treatment of specific chronic diseases in the alternate-site health care setting can improve health care and promote efficient use of health care dollars.  相似文献   
7.
Investigated the effects of acoustic similarity on memory span in 112 children ranging in age from 4 to 10 yrs. Ss were asked to recall lists of acoustically similar and dissimilar words. The lists alternated across trials while growing in length. Acoustic similarity had progressively more effect on recall with increasing age. There was a fairly sudden increase in recall of acoustically similar items by the 10-yr-olds, compared to the 9-yr-olds. The implications of this finding for current theories of short-term memory and its development and for the use of acoustic similarity as an indicator of speech coding are discussed. One possible account of the effects of acoustic similarity on recall is that it depends on the occurrence of confusions during rehearsal. The rate of rehearsal in young children may be too slow for significant numbers of confusions to occur and affect recall. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Immediate memory span and speed of memory search were assessed for words and nonwords of short and long spoken duration. Memory span was substantially greater for words than for nonwords and for short than for long items, though speed of memory search was unaffected by either length or lexicality. An analysis of the temporal pattern of responses in the memory span task indicated that inter-item pauses were longer between nonwords than words but that these pause durations were unaffected by item length. A model of verbal short-term memory span is described in which trace selection from a short-term store and the redintegration (restoration) of degraded phonological traces both occur in the pauses between saying successive items. Both trace selection and trace redintegration appear to play important roles in accounting for individual differences in memory span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Three candidate sex pheromone components, (Z)6,(Z)9-, (Z)6,(E)8-, and (Z)6,(E)9-heneicosadien-11-one (Z6Z9, Z6E8, and Z6E9) were identified in pheromone gland extracts of female Douglas-fir tussock moths (DFTM), Orgyia pseudotsugata (McDunnough). Their occurrence in subnanogram quantities in extracts and structural conversion during analytical procedures and bioassays complicated chemical identifications. Complete identification required comparative analyses of stereoselectively synthesized and female-produced dienones by coupled gas chromatographic–electroantennographic detection (GC-EAD), high-performance liquid chromatography (HPLC) and coupled GC–mass spectrometry (MS). Determination of the pheromone component was contingent upon an experimental design that minimized structural rearrangement of dienones before and during the field test. In a 40-min field experiment, acetonitrile solutions of each of the above dienones were carried on Dry Ice to traps and were syringed onto cotton release devices below trap lids. In combination with the previously known sex pheromone component of DFTM, (Z)6-heneicosen-11-one (Z6), Z6E8 was the only synergistic dienone and the mixture was highly attractive. Because Z6 by itself attracts seven species of tussock moths (two sympatric with DFTM), a blend of Z6 and Z6E8 may impart specificity to DFTM pheromone communication. In commercial lures, this binary blend may facilitate species-specific, sensitive monitoring and efficacious control by mating disruption of this important forest defoliator.  相似文献   
10.
R. B. Wardlaw  BSc  PhD  MICE  M. Hulme  BSc  PhD  FRMetS    A. Y. Stuck  BSc  MSc 《Water and Environment Journal》1996,10(5):355-364
Following the prolonged drought at the end of the 1980s in the south east of the UK, Anglian Water undertook (a) to review the reliable yields of their resource systems and (b) to investigate the potential risks associated with alternative future investment programmes. One of the major identifiable risks is climate change, and there is a clear need to understand how different scenarios of climate change could affect the reliable output of existing sources, and thereby affect investment programmes.
This paper highlights the approach which was adopted to model climate change impacts on rainfall, and on the limitations which exist for this type of assessment.  相似文献   
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