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181.
Water Resources Management - Frequently suffering from water deficits induced by prolonged and severe droughts in Taiwan, hedging rules become an important component in reservoir operation to...  相似文献   
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183.
Textural and rheological properties of raw, dried, and cooked noodles with microbial transglutaminase were evaluated by an instrumental texture analyser. Generally, the strength of the noodles significantly increased with microbial transglutaminase concentration from 0 to 1.0%. The cutting force of raw noodle is a good indicator to predict the strength of dried and cooked noodle products. Mechanical stress relaxation data of cooked noodles were fitted well by both Maxwell and Peleg-Normand models. The fitted parameters, λ1 and k2, were more sensitive to the changes in viscoelastic properties than k1 and %SR. Significant correlations were found between textural characteristics and stress relaxation parameters. Results of this study suggest that dried or cooked noodle with good quality can be produced by incubating with 0.5–1.0% microbial transglutaminase for 30 min at 30?°C.  相似文献   
184.
The toxicity and species of dried dressed fish fillets were investigated. Three of seven dried dressed fish fillets were found to be toxic, with their levels of toxicity ranging from 9 to 18 mouse units per g. The toxin preparation was further purified and identified as tetrodotoxin and anhydrotetrodotoxin by high-performance liquid chromatography and gas chromatography-mass spectroscopy. The species of these fillets could not be distinguished from Lagocephalus lunaris by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis or restriction site and sequence analysis of a polymerase chain reaction amplicon of the cytochrome b gene. These fish fillets were identified as L. lunaris on the basis of their protein patterns and gene characteristics. Furthermore, the toxic samples contained low levels of tetrodotoxin and its derivative.  相似文献   
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186.
In this paper, the charge pump (CP) based on a switches-in-source architecture is to be improved by gain-boosting amplifiers for phase-locked loops (PLLs). In our design, two differential amplifiers were employed in this CP to reduce the effect of the channel length modulation in MOS transistors. As a result, the up and down currents will be rather independent of the output voltage transformed by the capacitive low pass filter (LPF). This circuit was implemented using TSMC 0.18-μm CMOS technology and was investigated at a power supply of 1.8 V. The measured mismatch was less than 1% for the output voltage ranging from 0.4 to 1.4 V. This result is lower than that of the dynamic current-matching CP with feedback tuning on the same architecture. A comparison will be presented and discussed.  相似文献   
187.
Abstract

Superscalar processing can improve the performance of a single CPU beyond that of traditional RISC machines by exploiting instruction‐level parallelism. It is the objective of this study to design a superscalar system which will best exploit a given program's instruction‐level parallelism.

Three different architectural models, XPCB, XXPB, and X4P2, are used as vehicles in evaluating system performance and the degree of utilization of each individual functional unit. The XPCB model is used as a preliminary model to analyze the loading breakdowns of the various function types. It was found that the performance improvement of the XPCB model relative to a single‐instruction stream model is only about 4.3 percent. In addition, the fixed‐point operations are in great demand, and dominate the behavior as well as performance of the processor. Two enhanced models, the XXPB and the X4P2, are suggested to improve on the performance of the XPCB model by distributing fixed‐point, and even floating‐point operation loads among multiple functional units of the same type(s). Simulations show that the XXPB and X4P2 models can improve the performance of the sequential model by 50.8 and 61.6 percent, respectively.  相似文献   
188.
Abstract

The structure of the Reynolds stress in a turbulent flow over the multiple windbreaks of half‐circular sections across‐wind was investigated experimentally in the boundary layer wind tunnel. The quadrant analysis theory was applied to analyze the turbulent stress signals by partitioning the Reynolds stress into inward interaction, ejection, outward interaction, and sweep events in accordance with whichever quadrant the (u’, w‘)belongs to. u’ and w’ are the stream wise and transversewise velocity fluctuations, respectively The results show that when Z/H < 1, X/H < 20, the sweep events are the largest contributors to the Reynolds stress followed by the ejection events while the inward and outward interactions are negative contributors. Z is the distance from the wall, X is the downstream distance, and H is the height of windbreak. The stress contributions by sweeps and ejections are almost the same when Z/H < 1, X/H > 30.  相似文献   
189.
The impact of design on logistics cannot be ignored, and design for logistics is a new concept similar to design for manufacturing or design for assembly. Engineering change is one of the scenarios that would require logistics support. Change control of a product data management (PDM) system is one of the major approaches for handling engineering changes today. According to principles of configuration management, during the change control workflow, there are three different dates: release date, effective date, and effectivity date utilised for controlling and managing change planning and scheduling. Effective date is the exact date that a released change takes effect to the shop floor workshop. Effectivity date is the expected date that decision makers plan for the change to take effect. In normal situations, multiple disciplines, such as design and development, purchasing, shop floor workshop, quality control, and so on, are involved in making a change decision on when a change is to become effective. In this paper, a linear programming effectivity decision model is proposed to concurrently support changes of design scheduling, and production planning and scheduling when an engineering change occurs. The proposed model succeeded in solving an integration problem of design scheduling, production planning and shop floor scheduling.  相似文献   
190.
BACKGROUND: Soluble interleukin-2 receptor alpha (sIL-2R alpha) is a well-known indicator of T-cell activation noted to be increasing in nasopharyngeal cancer. However, the significance of sIL-2R alpha in monitoring disease relapse is unclear. This study was initiated to address this issue. METHODS: Serum of 56 patients with NPC, which underwent either primary, salvage, or palliative treatments, from 1992 to 1993 at the Cancer Center, Veterans General Hospital-Taipei, were collected from our serum bank. According to their disease status at the time of study, at least two years after last treatments, the 56 patients were divided into four groups. The remission group represented those in remission at the time of study (n = 24). The metastasis group represented those with distant metastasis present at the time of study (n = 17). The recurrence group represented those with locoregional recurrence present at the time of study (n = 11). The combined group represented those with locoregional recurrence as well as distant metastasis (n = 4). The seral sIL-2R alpha concentrations of the 56 NPC patients were determined with enzyme-linked immunoabsorbent assay. The combined group was excluded in our statistical analysis. We performed statistical analysis on the differences of paired serum sIL-2R alpha concentrations between different periods of the diseases. The first analysis was on the differences of sIL-2R alpha concentrations between diagnosis and post-radiotherapy periods for 13 out of 24 patients in the remission group and 7 out of 11 patients in the recurrence group. The second analysis was on the differences of sIL-2R alpha concentration between follow-up before detection-of-relapse and after detection-of-relapse for 5 out of 17 patients in the metastasis group and six out of 11 patients in the recurrence group. RESULTS: The first statistical analysis revealed no significant differences of sIL-2R alpha concentrations for the remission group (P = 0.946) and the recurrence group (P = 0.156) between diagnosis and post-radiotherapy periods. The second statistical analysis revealed no significant differences of sIL-2R alpha concentrations between before and after detection-of-relapse for the recurrence group, neither (P = 0.438). The results for the metastasis group were different. The sIL-2R alpha concentrations were shown to increase after the detection of metastasis for the 5 paired samples from the metastasis group, although the Wilcoxon signed ranks test on the differences only showed borderline significance (P = 0.063). CONCLUSIONS: Our findings show that sIL-2R alpha would be of no value in monitoring the development of locoregional recurrence but might be useful in monitoring distant metastasis. Although our current limited data did not provide strong support for the role of sIL-2R alpha in monitoring metastasis, it might be delineated in the future by collecting more data.  相似文献   
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