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61.
62.
The assessment of military camouflage is a key consideration in the modern military field. Traditionally, the assessment relies on traditional human visual detection tests because a large scale multi‐level and multi‐factor experiments are time‐ and resource‐consuming. One aspect of camouflage assessment, to which this current study pertains, entails improving upon or “enhancing” an existing or “selected” design. The current study presents a new and practical approach for enhancing the selected military camouflage by utilizing response surface methodology (RSM) of %L*, %a*, and %b* in CIELAB color space. Ten participants were recruited to evaluate 35 variations of %L*, %a*, and %b* on camouflage similarity index (CSI) and reaction time (RT). Based on RSM, the optimum combination occurs at L*: 61.4966, a*: ?5.6505, and b*: 10.5114. In addition, a predictive algorithm to calculate the optimum shift of %L*, %a*, and %b* from the original camouflage to the improved camouflage derived from RSM is also proposed. The optimum shift occurs at ?25%L*, ?55%a*, and + 80%b*. In the end, a new design guideline is proposed for the enhancement of selected military camouflage, which adopts the present study's research findings.  相似文献   
63.
This paper describes one anthropomorphic modular reconfigurable gripper for robots, including a prototype and one command solution. For the first time the stages of synthesis, analysis design and functional simulation are presented. The structural synthesis of the anthropomorphic grippers for robots can be made regarding the following main criteria: the number of fingers, the number of phalanxes, the relative dimensions of the phalanxes, the relative position of the fingers, the degree of freedom of the gripping mechanism and the characteristic constructive elements used. We have chosen a version with three identical fingers with three phalanxes on finger. The kinematic synthesis is used to obtain a correct closing of the finger and of the gripping mechanism. The static synthesis solves the problem to obtaining the necessary gripping force on each finger and the total gripping force. With the constructive dimensions a 3D model can be obtained using CATIA soft. Aspects regarding functional CAD and virtual simulations are shown too. For one variant of this type of gripper, the technical documentation is completed and the technical project has all the conditions for practical achievement and a prototype was made. There are two main constructive modules: the support, the palm and the finger. Main technical characteristics of the prototype are indicated. Some aspects regarding actuated and command schemes are shown.  相似文献   
64.
Religion helps people maintain a sense of control, particularly secondary control—acceptance of and adjustment to difficult situations—and contributes to strengthening social relationships in a religious community. However, little is known about how culture may influence these effects. The current research examined the interaction of culture and religion on secondary control and social affiliation, comparing people from individualistic cultures (e.g., European Americans), who tend to be more motivated toward personal agency, and people from collectivistic cultures (e.g., East Asians), who tend to be more motivated to maintain social relationships. In Study 1, an analysis of online church mission statements showed that U.S. websites contained more themes of secondary control than did Korean websites, whereas Korean websites contained more themes of social affiliation than did U.S. websites. Study 2 showed that experimental priming of religion led to acts of secondary control for European Americans but not Asian Americans. Using daily diary methodology, Study 3 showed that religious coping predicted more secondary control for European Americans but not Koreans, and religious coping predicted more social affiliation for Koreans and European Americans. These findings suggest the importance of understanding sociocultural moderators for the effects of religion. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
65.
The mean color errors of a high‐quality digital camera are defined in CIELAB and CIEDE2000 ΔE units by using 16 ceramic color samples, whose accurate CIELAB values have been measured by a calibrated spectrophotometer. The bandwidths of CCD's color filters are evaluated by taking photographs of CRT‐display primaries. The lowest mean color errors were 13.1 CIELAB ΔE units and 8.1 CIEDE2000 ΔE units before corrections. Large color errors are decreased successfully by using three different methods: simple photoeditor, gamma correction, and multiple regression. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 217–221, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20007  相似文献   
66.
This aim of this study was to optimize the conditions for efficient saccharification of paper sludge (PS) considering PS cellulose concentration, buffer capacity, and cellulase activity from Acremonium cellulolyticus. PS is a cellulosic biomass, the residue of paper making industry, composed of 24.5% cellulose, 10.5% clay, and 65% water. Clay present in PS did not show any inhibitory effect on the saccharification process but influenced the buffer pH. Maleate buffer in the pH range 5.2–5.6 was suitable for the saccharification of PS cellulose. The maximum reducing sugar concentration that could be obtained from 75.6 kg m?3 of PS cellulose was predicted to be 37.8 kg m?3. This was experimentally confirmed to be 38.4 kg m?3 under the optimal saccharification conditions at pH 5.2 (1.06 kmol m?3 Maleate buffer) using Cellulase 20,000 FPU m?3. Almost 100% saccharification yield (SY) was obtained at a low PS cellulose concentration of 15 kg m?3, but this value decreased when the cellulose content increased. When PS was hydrolyzed with commercial cellulase GC220, the SY and glucose content were 54% and 60% of SY, respectively. The corresponding values with Cellulosin T2 were 63% and 75% of SY, respectively. A. cellulolyticus yielded SY and glucose content values almost 10% higher than those obtained with other cellulases.  相似文献   
67.
68.
Abstract

Hardwood (Betula pendula) chips were extracted having alkaline aqueous solutions with varying chemical charges (1, 2, 3, 4, 6, and 8% of NaOH on wood), treatment times (30, 60, 90, and 120 minutes), and temperatures (130°C and 150°C). The total amount of material removed was in the range 2.1–16.5% of the original dry feedstock. This fraction was characterized in terms of carbohydrates and their degradation products (mainly aliphatic carboxylic acids together with some furanoic compounds), lignin, and extractives. Low alkali charges (1–4% of NaOH) were not sufficient to neutralize all the acids formed (mainly acetic acid from the acetyl groups of xylan). In contrast, an increase in alkali charge (6% and 8% of NaOH) more intensively facilitated the alkali-catalyzed degradation reactions of polysaccharides to various hydroxy acids, which were then typically present as one of the main constituents in the dissolved organic matter, along with other aliphatic carboxylic acids (acetic and formic acids), lignin, extractives, and carbohydrates.  相似文献   
69.
With the use of individual-level travel survey datasets describing the detailed activities of households, it is possible to analyze human movements with a high degree of precision. However, travel survey data are not without quality issues. Potential exists for origins and destinations of reported trips not to be geo-referenced, perhaps due to misreported information or inconsistencies in spatial address databases, which can limit the usefulness of the survey data. From an analytical standpoint, this is a serious problem because a single unreferenced stop in a trip record in effect renders that individual’s data useless, especially in cases where analyzing chains of activity locations is of interest. This paper presents a framework and basic computational approach for exploring unlocatable activity locations inherent to travel surveys. Derived from recent work in developing a network-based, probabilistic time geography, the proposed methods are able to estimate the likely locations of missing trip origins and destinations. The methods generate probabilistic potential path trees which are used to visualize and quantify potential locations for the unreferenced destinations. The methods are demonstrated with simulated survey data from a smaller metropolitan area.  相似文献   
70.
Additive colour mixing produced by diffractive grating structures is studied. The gratings produce almost monochromatic primary colours to a selected viewing angle, providing thus a very large colour gamut. The colours inside the gamut are obtained by additive colour mixing in the reflected diffraction order. The amount of a single primary in the additive colour mixing within one colour pixel is determined by the area fraction of the corresponding grating. We demonstrated the concept by fabricating samples which appear white at 30° viewing angle when illuminated by 4000?K fluorescent lamp.  相似文献   
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