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101.
102.
The self-assembled domain patterns of modulated systems are the result of competing short-range attractive and long-range repulsive interactions found in diverse physical and chemical systems. From an application point of view, there is considerable interest in these domain patterns, as they form templates suitable for the fabrication of nanostructures. In this work we have generated a variety of new and exotic patterns, which represent either metastable or glassy states. These patterns arise as a compromise between the required equilibrium modulation period and the strain resulting from topologically constrained trajectories in phase space that effectively preclude the equilibrium configuration.  相似文献   
103.
Organochlorine pesticide residues were measured in human serum from an urban and two rural populations in Portugal, in an attempt to evaluate the contamination level of Portuguese population. Serum levels of 12 residues were determined using a validated methodology that included gas chromatography-electron-capture detection. It was made an attempt to point out the differences of contamination between rural and urban populations; and among these, if it could be established a relation with sex and with age of individuals. p,p'DDE, alpha-hexachlorocyclohexane (HCH), p,p'DDD, and beta-HCH were the most frequently identified residues. p,p'DDE concentrations ranged from undetected to 390.5 microg/l in urban samples, and from undetected to 43.5 microg/l and to 171.2 microg/l in both rural samples. Maximum alpha-HCH concentration level was 114.4 microg/l in urban samples, 261.3 and 45.5 microg/l in both rural samples. Mean total DDT levels were always higher than mean total HCH levels. About p,p'DDE, in all three populations, the majority of the results above the limit of quantification were found among female sex. The analysis of different aged groups showed that younger groups continue to reveal contamination. Comparing obtained results with others from Europe, Asia and America, it was observed that Portugal is between the highest levels of contamination.  相似文献   
104.
A landmark based navigation system for robotic wheelchairs is developed. The proposed navigation system is robust in the localization procedure which is the major problem in robotic navigation systems. Every landmark is composed of a segment of metallic path and a radio-frequency identification (RFID) tag. The odometry information is used for localization, which is corrected on-line every time the robotic wheelchair is over a landmark. A topological map is generated using such landmarks to compute the shortest path. A technique to generate the topological map for this navigation system and an obstacle avoidance strategy are also developed.  相似文献   
105.
This study investigated differences in standard measurements used to determine bra size, under-bust chest circumference (UBCC) and over-bust chest circumference (OBCC), measured from a three-dimensional scan (hand-held scanner) compared to the direct measurement in 111 women (age 21–56 years; right breast volume 57–1672 mL; bra size 10A–18G). Bland–Altman plots of UBCC measurements showed a large positive bias and wide limits of agreement (12 cm; ?4.6 to 28 cm), which increased as band size increased but decreased when the breasts were digitally removed from the scan prior to the UBCC measurement. The difference in UBCC measurements determined from scans compared to direct measurement had a strong positive correlation with breast volume and breast ptotis. The OBCC measurements showed a small positive bias (2.4 cm; ?3.4 to 8.4), consistent across the range of bra sizes. Bra band size measurements determined from three-dimensional scans can be inaccurate in women with large, ptotic breasts.

Practitioner Summary: We investigated potential errors in anthropometric data derived from three-dimensional scans used for bra design and fit. Bra band size measurements taken from three-dimensional scans were over-estimated in women with large breasts, whereas bra cup size measurements were accurate to within one-cup size across the entire range of bra sizes.  相似文献   
106.
The current work investigates the use of interface agents as anthropomorphic social models to influence young women’s negative beliefs and low self-efficacy regarding engineering. Experiment 1 focused on the impact of agent model visual presence vs. voice alone for changing the women’s beliefs. Based on literature on human social models we hypothesized that the visual presence of the interface agent would result in more positive attitudes toward engineering and greater self-efficacy than the presence of a human voice alone. Experiment 2 focused on the impact of model appearance-related characteristics for changing the women’s beliefs. Previous work with human social models suggests that people are more persuaded by models that are similar to them. Therefore, models that were young, female, and “cool” were predicted to be more effective in influencing young women’s attitudes. In accordance with our hypothesis, results revealed that participants who interacted with the visible agents reported significantly greater utility for engineering, greater self-efficacy, and greater interest in engineering-related fields than those who interacted with a human voice. In addition, the agent models that were similar to the young women tended to be the most effective for positively influencing the women’s stereotypes and self-efficacy.  相似文献   
107.
Biofuels have emerged as an attractive renewable alternative to satisfy the global energy demands. The large-scale production of biofuels requires the installation of biorefining systems that involve strategic decisions for the logistics and operation in the production of biofuels such as location, feedstock type(s), production capacities and interactions with the surrounding environment. This work proposes an optimization framework for the design of a biorefining system while accounting for the interactions with the surrounding watershed using a material flow analysis technique through the design of an efficient supply chain for the production and distribution of feedstocks, grains and biofuels considering the water and land requirements. The proposed model deals with the uncertainty involved in the project (e.g., prices of feedstocks and products, biofuel demands and precipitation in the watershed). A mixed-integer linear programming model is proposed to simultaneously consider the economic and environmental objectives. A case study located in Mexico is solved for a set of scenarios with the purpose of illustrating the capabilities of the proposed optimization approach. The results show strong trade-offs between the considered objectives and the impact of uncertainties.  相似文献   
108.
Quantum dots can be used to perform multicolor images with high fluorescent intensity and are of a nanosize suitable for lymphatic imaging via direct interstitial injection. Here simultaneous multicolor in vivo wavelength-resolved spectral fluorescence lymphangiography is shown using five quantum dots with similar physical sizes but different emission spectra. This allows noninvasive and simultaneous visualization of five separate lymphatic flows draining and may have implications for predicting the route of cancer metastasis into the lymph nodes.  相似文献   
109.
A novel non-intrusive measurement system based on quantitative infrared imaging has been designed and developed specifically for the study of composite plates submitted to fire. The system consists of two synchronized infrared cameras that image both sides of the sample during a fire test, providing surface temperature maps spatially corregistered. Flame effects on measured temperature are minimized through selection of a spectral band with near negligible infrared absorption-emission (wavelength centre 9585 nm, full width at half maximum 135 nm), as well as software post-processing. An ad hoc experiment has shown that this procedure retrieves surface temperatures with an uncertainty of \(\pm 5\) K, compared to a systematic error larger than 60 K for a classic thermographic measurement. Surface emissivities of both sides of the sample are measured and included in the retrieval procedure. By adding a flash lamp, the system implements an adaptation of the classical Parker’s flash method to thermally thick samples, providing also a map of thermal diffusivities along the sample both before and after the burning. In the region most degraded by fire, the effective thermal diffusivity is reduced approximately one order of magnitude as compared to the pre-test value (from 5.9 × 10?7 m2 s?1 to 0.5 × 10?7 m2 s?1). Several composite samples have been analysed while exposed to fire in different conditions, showing that thermal diffusivity after the burning shows a strong correlation with the local maximum temperature reached during the test. More precisely, in the temperature range between \(\sim \)325 and 350\(^{\circ }\)C a drastic change in diffusivity seems to takes place, in a way that suggest a phase change.  相似文献   
110.
Mechanically deboned chicken meat (MDCM) is a meat product obtained by crushing tissues after meat removal and is largely used in meat products. Protein quality of flour prepared from defatted MDCM and from fresh chicken breast meat (FCBM) was chemically and biologically evaluated by rat growth and nitrogen balance studies. Proximate chemical composition, on a dry basis, of MDCM and FCBM showed protein contents of 90.5% and 82.2%, lipid contents of 3.0% and 13.2% and ash contents of 6.1% and 4.2%, respectively. There was a relatively good balance of essential amino acids in both samples although lysine was in low concentration in MDCM being a limiting amino acid. Feeding of flour diets resulted in high protein efficiency ratio, a high net protein utilization and high nitrogen balance, thus showing a high biological value and also high true digestibility and, consistently, NPU for both samples is similar to casein.  相似文献   
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