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181.
Nowadays a sophisticated match-making mechanism is necessary for appropriate collaborations in virtual enterprise (VE). Virtual market based match-making operation enables effective partner search in terms of products allocation by distributing the scheduled resources according to the market prices, which define common scale of value across the various products. We formulate the VE match-making model as discrete resource allocation problem, and propose a complex market-oriented programming framework based on the economics of complex systems. Three types of heterogeneous agents are defined in the complex virtual market. It is described that their interactions with micro behaviour emerge a macro order of the virtual market, and the clearing price dynamism can be analysed in economic terms. The applicability of the framework into resource allocation problem for VE is also discussed.  相似文献   
182.
Environmental Impact of Solid Waste Treatment Methods in Korea   总被引:1,自引:0,他引:1  
The environmental impact of various solid waste treatment methods being used in Korea was assessed to provide useful information for decision making in solid waste management strategy. Among the treatment methods considered, the incineration method and the anaerobic digestion method are the most environmentally friendly, while the landfill method has the highest environmental impact. Regarding the life cycle of the treatment methods, the environmental impact of the main treatment stage is the largest, contributing 46–94% of the total impact, depending on the treatment method. The environmental impact due to wastewater treatment was 6.2, 0.2, 4.1, and 9.0% for landfilling, incineration, composting, and anaerobic digestion, respectively. Among the environmental impact categories considered, global warming, eutrophication, and acidification are the key contributors to environmental impact, with a range of 53 to 91% of the total environmental impact depending on the selected treatment method. Of these key contributors, global warming has the largest contribution. Other contributors to environmental impact, such as photochemical oxidant creation, abiotic resource depletion, and ozone depletion, contribute little to the total environmental impact. These results make it possible to construct an environmental data set and examine the environmental impact of the life cycle of various waste treatment methods to support decision making in solid waste management strategy.  相似文献   
183.
184.
Diagnostic technology for photovoltaic (PV) systems was developed, using the learning method to take each site’s conditions into account. This technology employs diagnostic criteria databases to analyze data acquired from the PV systems. These criteria are updated monthly for each site using analyzed data. To check the shadows on the PV modules and pyranometer, the sophisticated verification method was also applied to this technology. After the diagnosis, a basket method provides maintenance advice for the PV systems. Based on the results of precise diagnoses, this expert system offers quick and proper maintenance advice within a few minutes. This technology is highly useful, because it greatly simplifies the servicing and maintenance of PV systems.  相似文献   
185.
Energy-saving technologies’ applicability to making cities more environmentally sustainable can be strongly influenced by the city's form, building uses and their density pattern. Technological developments have clearly shown specific urban forms to be more conducive to installing certain mitigation technologies. In this study, the capacity for implementation and impacts on energy savings and subsequent greenhouse gas (GHG) reduction potential of mitigation technologies such as photovoltaic cells (PV) and combined heat and power (CHP) technologies were analysed with respect to three potential urban forms (high density centralised, medium density averaged and low density de-centralized) for Utsunomiya City, Japan. Given current building use patterns, scenarios for 2030 and 2050, showed the medium density averaged form, which benefits from both PV and CHP technologies, to outperform the other forms, resulting in an energy savings and GHG reduction potential of 27.6% in 2030 and 67.6% in 2050. Interestingly, GHG reduction in 2050 was primarily attributable to PV, while CHP technology had the greater influence in 2030. Despite the limitation of the analysis, the study provides a useful insight, highlighting the relationship between urban forms and GHG reduction potential by two energy-saving technologies.  相似文献   
186.
Vertical-type coils arranged perpendicular to conductor slabs have proven useful for nondestructive testing. Because the fork–coil method offers the advantage that the lift-off effect is fundamentally removed, we analyze a fork-shaped rectangular coil oriented perpendicular to conductor slabs. Our calculations elucidate some characteristics of the conductor and the coil arrangement as a function of system parameters such as the slab dimensions, speed, and direction of motion. We validate the results of the calculation by comparing them with experimental results.  相似文献   
187.
A study on the effects of processing additives on the nanoscale phase separation, crystallization, and photovoltaic performance of bulk heterojunction (BHJ) thin films made of 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2) and [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) via spin-casting for photovoltaic applications is reported. By incorporating various solvents as processing additives to a volume of a few percent, the separation of donor and acceptor phases in C6PcH2:PCBM thin films, which discussed by taking the photoluminescence quenching, Davydov splitting at the Q-band of the absorbance spectra and the surface nanomorphology into consideration, is improved, and the crystallinity of the discotic C6PcH2 molecules with hexagonal structures is reinforced. Photovoltaic cells with the optimum phase-separated BHJ materials and high crystallinity of the discotic C6PcH2 molecules are demonstrated to have a power conversion efficiency of 4.2%.  相似文献   
188.
189.
Abstract— In this paper, the relative influences of misalignment such as cross‐talk, vertical shift, and motion blur on visual fatigue by using a binocular stereoscopic display has been verified. Experiments were conducted for two cases: a still image and a motion image. They were evaluated by using the simulator sickness questionnaire (SSQ). By changing the disparity angle, cross‐talk, and vertical shift in the still‐image experiment, it was found that the SSQ score of each parameter increased as the amount of each factor increased. With a two‐sample t‐test between the presence and absence of each factor, a significant difference was found for the case of a more than 36‐arcmin disparity, more than 20% cross‐talk, and more than 10% vertical shift. In the motion‐image experiment, in which motion speed and the misalignment were varied, it was found that movement of the disparity angle caused much more visual fatigue in comparison with the misalignment factors, which were cross‐talk and vertical shift. In contrast, motion images in addition to the cross‐talk and/or vertical shift had a slight but unnoticeable relationship to an increase in visual fatigue. Therefore, it was concluded that vertical shift dominated the evaluation for still images, and the movement itself dominated the evaluation for motion images. The results suggest that it is necessary to evaluate visual fatigue according to the representing case, still or motion images, of a 3‐D stereoscopic display.  相似文献   
190.
We propose an optical projection system aimed at improving laparoscopic surgery based on three-dimensional (3D) measurement that gives an effective information for robotic-assisted surgery and computer-aided surgery. Laparoscopic surgery, which involves the creation of small ports through the patient’s body for the laparoscope and surgical instruments, such as clamp, is minimally invasive and has generated a growing interest. There are techniques using the stereo laparoscope to obtain depth information. Active sensing when structured light is added to the laparoscope can reconstruct a 3D shape. However, active sensing that requires projection devices for the structured light leads to an increase in size. Large-sized projection and sensing systems affect surgical procedures. The size of the system is also larger than the size of port for the laparoscope. To remove the obstacle for the surgery, it is important to design downsized systems. For active sensing with the structured light, a small-size projection system is required to use a small port for the laparoscope. Therefore, we built the optical projection system toward downsizing the device to stereoscopic vision of the laparoscope using mirrors, and we show a new shape reconstruction method from its active sensing. Our Experimental results demonstrate the effectiveness of this proposed system and method.  相似文献   
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