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71.
Debbie Tesch Marion G. Sobol Gary Klein James J. Jiang 《International Journal of Project Management》2009,27(7):657-664
Since Information Systems Development (ISD) project success is difficult to achieve and the literature has shown the relationship between IS developer skills and system success is mixed, this paper isolates and studies the knowledge shared by users and developers and its interaction with group solving practices that may lead to ISD project success. We evaluate developer’s knowledge of application domains and user knowledge of IS development along with the level of group problem solving among users and developers as related to the ultimate success of the project. A survey of 168 ISD professionals indicates that a combination of both user knowledge of IS development and IS developer knowledge of application domains had significant impact on successful project outcomes. The magnitude of this success is moderated by the level of group problem solving activities held by the project implementation teams. Up to a certain point, the more group problem solving interaction the more successful the project outcome. However, if knowledge redundancy is very high then exchange of knowledge is not so essential. 相似文献
72.
Adult humans searched for a hidden goal in images depicting 3-dimensional rooms. Images contained either featural cues, geometric cues, or both, which could be used to determine the correct location of the goal. In Experiment 1, participants learned to use featural and geometric information equally well. However, men and women showed significant differences in their use of distant featural cues and the spontaneous encoding of geometric information when trained with features present. Transformation tests showed that participants could use either the color or the shape of the features independently to locate the goal. Experiment 2 showed that participants could use either configural or surface geometry when searching for the goal. However, their weighing of these geometric cues was dependent on initial training experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Danforth Jeffrey S.; Allen Keith D.; Fitterling James M.; Danforth Julie A.; Farrar Debbie; Brown Melissa; Drabman Ronald S. 《Canadian Metallurgical Quarterly》1990,58(2):237
Low-socioeconomic-status (SES) Black children have a higher mean blood pressure than most other groups. The antihypertensive effects of a 12-week aerobic exercise program were examined on 11 low-SES Black children, ages 8–12, who had blood pressure above the 95th percentile. A multiple baseline across three groups of children with baseline and exercise conditions was conducted. After the introduction of the exercise program, there were significant decreases in diastolic and systolic blood pressure. Cardiovascular fitness improved concurrently. The results suggest that vigorous exercise can decrease the blood pressure of low-SES hypertensive Black children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Merging individual conceptual models of requirements 总被引:2,自引:2,他引:0
75.
Weaned pigs were separated into eight treatments including a control without exposure to apramycin; a control with exposure to apramycin; and apramycin plus either cold stress, heat stress, overcrowding, intermingling, poor sanitation, or intervention with oxytetracycline, to determine the effects of management and environmental conditions on antibiotic resistance among indigenous Escherichia coli. Pigs exposed to apramycin sulfate received that antibiotic in the feed at a concentration of 150 g/ton for 14 days. Environmental treatments were applied 5 days following initial antibiotic administration and maintained throughout the study. Fecal samples were obtained on day 0 (prior to antibiotic treatment) and on days 2, 7, 14, 28, 64, 148, and 149. E. coli were isolated and tested for resistance to apramycin using a minimum inhibitory concentration (MIC) broth microdilution method. Macrorestriction profiling, arbitrarily primed PCR, PCR targeting a gene coding for apramycin resistance, and DNA hybridization were used to characterize genetic elements of resistance. Increased (P<0.0001) resistance to apramycin was noted in E. coli from all treatment groups administered apramycin. MICs of isolates from control pigs receiving apramycin returned to pretreatment levels following removal of the antibiotic, whereas isolates from cold stress, overcrowding, and oxytetracycline groups expressed greater (P<0.05) MICs through day 64, before returning to pretreatment levels. Genetic analysis indicated that all resistant isolates carried the aac(3)IV gene sequence and this sequence was found in a variety of E. coli isotypes. Our data indicate that E. coli resistance to apramycin is increased upon exposure to various stressors. 相似文献
76.
The doping of the wide-band gap semiconductor diamond has led to the invention of many electronic and optoelectronic devices. Impurities can be introduced into diamond during chemical vapor deposition or high pressure-high temperature growth, resulting in materials with unusual physical and chemical properties. For electronic applications one of the main objectives in the doping of diamond is the production of p-type and n-type semiconductors materials; however, the study of dopants in diamond nanoparticles is considered important for use in nanodevices, or as qubits for quantum computing. Such devices require that bonding of dopants in nanodiamond must be positioned substitutionally at a lattice site, and must exhibit minimal or no possibility of diffusion to the nanocrystallite surface. In light of these requirements, a number of computational studies have been undertaken to examine the stability of various dopants in various forms of nanocrystalline diamond. Presented here is a review of some such studies, undertaken using quantum mechanical based simulation methods, to provide an overview of the crystal stability of doped nanodiamond for use in diamondoid nanodevices. 相似文献
77.
78.
The ability to model air quality dispersion at increasingly smaller resolutions requires a concomitant improvement in the resolution of the gridded mobile source emissions used as input to these models. Two methods are currently used to allocate mobile emissions to grids; because of the limitations associated with these methods, their application is usually restricted to coarser grid resolutions. This paper uses a new mobile emissions inventory model (UCDrive) to explore the spatial distribution of mobile source emissions using finer grid cell resolutions. Our results indicate that the new model improves the precision of the spatial allocation of mobile source emissions, which in turn improves our ability to identify and implement pollutant control strategies. 相似文献
79.
The application of a variety of reservoir yield estimation methods is described against the background of a review of yield in Scotland. The study is timely, both in the context of the possible effects of climate change, the institutional re-organisation of the water industry world-wide--but originating largely from the UK-and the emerging issues of sustainability and the shift from supply to demand side management. To set the paper in context, the study was undertaken just prior to the transfer of responsibility for water supply from regional councils to new water authorities in 1996, and following the quinquennial Scottish Office Environment Department's survey of water resources in 1994. A comparative review of assessment methods was undertaken in order to recommend a flexible and consistent approach for single sources, but with a view to extending this to conjunctive schemes. A case study of Loch Bradan showed that the derivation of the inflow record and definition of the catchment boundary are at least as important as the yield assessment method itself. 相似文献
80.
Energy-efficiency is an essential feature of wireless sensor networks (WSNs) where the longevity of autonomous sensor nodes
is limited by their battery life and/or energy-harvesting capability. Base-station-initiated optical wireless communication
with nodes equipped with a passive optical transmitter in the form of a corner cube retroreflector (CCR) provides sensor acquisition
with no energy expenditure on the part of the sensor node itself and is therefore an attractive option for WSN. However, the
return signal from an illuminated sensor node is a stochastic variable dependant on fabrication parameters, ambient conditions
and receiver noise so that the sensor acquisition process is inherently error-prone. In this paper we propose an energy-aware,
base station-initiated interrogation scheme based on exponentially increasing beam scan areas, that takes into consideration
the error-prone trait of CCR-outfitted sensor nodes. We analyse the scheme performance subject to different values of signal
variance and various cost functions. We extend the analysis to address the circumstance of a spatially-limited sensor-failure
event, such as may be caused by deliberate tampering or by environmental factors. We show that agile beam-steering on the
basis of accrued knowledge of contaminated sensor distributions promotes energy-conserving acquisition. The validity of a
Poisson spatial distribution model for the sensor dispersion is discussed and the impact of this initial assumption on acquisition
error is demonstrated. 相似文献