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191.
192.
Two bodies of work on postpartum depression are reviewed. Quantitative, positivist studies examine the epidemiology and etiology of postpartum depression, adopt a medical model of explanation, and conceptualize postpartum depression as a pathological response to motherhood. Social scientific studies, some from a feminist perspective, explore women's experiences of postpartum depression predominantly, but not exclusively, within a qualitative tradition. Postpartum depression is theorized as a "normal" response to motherhood and is linked to "public-world" losses of identity, autonomy, independence, power, and paid employment. Drawing on a qualitative study of 40 women's experiences of motherhood, this article argues that not all women become depressed following childbirth and women's varying responses to motherhood need to be recognized. A relational re-framing of postpartum depression is put forward. From this perspective, postpartum depression occurs when women are unable to experience, express, and validate their feelings and needs within supportive, accepting, and non-judgmental interpersonal relationships and cultural contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
193.
Accompanied by the guest-editors of this issue, Natasha Nicholson and Pamela Charlick take an exhilarating ride beyond the Thames Estuary, off the coast of Herne Bay, on Bayblast, the rigid hull inflatable boat (RHIB) - a trip that takes in the impressive Kentish Flats wind farm, under construction, and the Maunsell Forts. With substantial-scale projects already nestled in the estuary, new possibilities for architectural interpretation can be thrown up for the Thames Gateway flood plain. However, what potential contribution might the wind farm also make to the area in terms of power generation?  相似文献   
194.
Impoundment effects override natural, reach-based channel geomorphology influences on seasonal waterbird distribution in Grand Canyon along the Colorado River downstream from Glen Canyon Dam. Large winter waterbird populations were rare or non-existent prior to completion of Glen Canyon Dam in 1963, and pre-dam summer breeding was rare. Post-dam river corridor surveys of 13 geomorphological reaches from 1973 to 1994 detected 58 species of waterfowl, waders, shorebirds and piscivorous raptors, with a grand mean of 138·2 waterbirds/reach (SE=31·0, n=727 reach surveys), and a mean area-adjusted rate of encounter (AARE) of 372·8 waterbirds km−1 h−1 of observation per reach (SE=69·1). The post-dam assemblage has been dominated by Anseriformes (13 diving and 12 dabbling species) and includes regionally significant populations of wintering waterfowl and bald eagle, and breeding mallard. Most wading birds and shorebirds occur primarily as migrants or summer vagrants. Total waterbird AARE was greatest in the productive clear water (CW) and variably turbid (VT) segments upstream from the Little Colorado River (LCR) (km 98), decreasing downstream on the usually turbid (UT) lower Grand Canyon segment. Mean total winter waterfowl AARE was 1076·8, and decreased by three orders of magnitude from the CW to the UT segments (p=0·0001). Mean total summer AARE was 2·7, and also decreased across the turbidity segments (p=0·066). In contrast, AARE varied little between wide and narrow geomorphological reaches. Total AARE was only 1·4 and 1·3-fold greater in wide versus narrow reaches within the VT and UT turbidity segments, respectively (p<0·0002). Winter AARE was threefold greater (p=0·0002), while summer AARE was equivalent between wide and narrow reaches. These tributary-related turbidity and geomorphological reach width factors contributed to a non-linear, circuitous shift in the waterbird assemblage over distance downstream from the dam, differentially affecting the seasonal distribution of waterbird feeding guilds. We discuss flow regulation and habitat management implications. © 1997 John Wiley & Sons, Ltd.  相似文献   
195.
From a self-determination perspective, we attempted to replicate previous findings suggesting that higher autonomous environmental motivation (i.e., acting out of choice and pleasure) is associated with the frequency of environmental behaviours such as recycling, paper reuse, and energy conservation. We also compared students' level of autonomous environmental motivation with their level of autonomous academic motivation. We then examined age effects on autonomous environmental motivation and compared them to age effects on autonomous academic motivation. A total of 200 high school students grouped into 5 age cohorts filled out a questionnaire. Results showed that (1) adolescents' autonomous environmental motivation was associated with more frequent environmental behaviours, (2) autonomous motivation was higher in the environmental than the school domain, and (3) autonomous environmental motivation was higher in older than younger students, whereas autonomous motivation toward school was equivalent across age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
196.
A typical data-driven visualization of electroencephalography (EEG) coherence is a graph layout, with vertices representing electrodes and edges representing significant coherences between electrode signals. A drawback of this layout is its visual clutter for multichannel EEG. To reduce clutter, we define a functional unit (FU) as a data-driven region of interest (ROI). An FU is a spatially connected set of electrodes recording pairwise significantly coherent signals, represented in the coherence graph by a spatially connected clique. Earlier we presented two methods to detect FUs: a maximal clique based (MCB) method (time complexity O(3n/3), with n being the number of vertices) and a more efficient watershed based (WB) method (time complexity O (n2 log n)). To reduce the potential over-segmentation of the WB method, we introduce here an improved WB (IWB) method (time complexity O(n2 log n)). The IWB method merges basins representing FUs during the segmentation if they are spatially connected and if their union is a clique. The WB and IWB methods are both up to a factor of 100,000 faster than the MCB method for a typical multichannel setting with 128 EEG channels, thus making interactive visualization of multichannel EEG coherence possible. Results show that considering the MCB method as the gold standard, the difference between IWB and MCB FU maps is smaller than between WB and MCB FU maps. We also introduce two novel group maps for data-driven group analysis as extensions of the IWB method. First, the group mean coherence map preserves dominant features from a collection of individual FU maps. Second, the group FU size map visualizes the average FU size per electrode across a collection of individual FU maps. Finally, we employ an extensive case study to evaluate the IWB FU map and the two new group maps for data-driven group analysis. Results, in accordance with the conventional findings, indicate differences in EEG coherence between younger and older adults. However, they also suggest that an initial selection of hypothesis-driven ROIs could be extended with additional data-driven ROIs.  相似文献   
197.
In their recent article, N. Spillane and G. Smith (see record 2007-06095-002) suggested that reservation-dwelling American Indians have higher rates of problem drinking than do either non–American Indians or those American Indians living in nonreservation settings. These authors further argued that problematic alcohol use patterns in reservation communities are due to the lack of contingencies between drinking and “standard life reinforcers” (SLRs), such as employment, housing, education, and health care. This comment presents evidence that these arguments were based on a partial review of the literature. Weaknesses in the application of SLR constructs to American Indian reservation communities are identified as is the need for culturally contextualized empirical evidence supporting this theory and its application. Cautionary notes are offered about the development of literature reviews, theoretical frameworks, and policy recommendations for American Indian communities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
198.
199.
While response time and accuracy indicate overall performance, their value in uncovering cognitive processes, underlying learning, is limited. A promising online measure, designed to track decision-making, is computer mouse tracking, where mouse attraction towards different locations may reflect the consideration of alternative response options. Using a speedy arithmetic multiple-choice game in an online adaptive learning environment, we examined whether mouse movements could reflect arithmetic difficulties when error rates are low. Results showed that mouse movements towards alternative responses in correctly answered questions mapped onto the frequency of errors made in this online learning system. This mapping was stronger for the younger children, as well as for easy arithmetic problems. On an individual level, users showed more mouse movement towards their previously made response errors than towards other alternative options. This opens the possibility of adapting feedback and instruction on an individual basis through mouse tracking.  相似文献   
200.
Clean Technologies and Environmental Policy - The production of dairy products is related to water and energy costs and generation of large amounts of emissions of pollutants. Full sustainability...  相似文献   
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