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Presence is usually assessed via a variety of subjective and objective measures. However, constraints often result in subjective measurements using questionnaires as a key method of data collection. In this paper we present a study of 44 participants of a collaborative augmented reality game known as TimeWarp which used both subjective and objective behavioral measures. Behavior as coded from video recordings of one scene of the game and self-reports about feelings of presence were compared. Our findings indicate that pointing behavior and verbal responses to the virtual content are correlated negatively to sense of presence. We further investigated the influence of subjectively perceived interactivity on perceived presence. We found that the interaction possibilities perceived by the participants predicted their experience of social presence with the virtual characters in the game. Furthermore, playing together with another person did not result in decreased social presence of the virtual characters. Implications for presence research are discussed.  相似文献   
995.
This study examined the affective dysregulation component of borderline personality disorder (BPD) from an emotional granularity perspective, which refers to the specificity in which one represents emotions. Forty-six female participants meeting criteria for BPD and 51 female control participants without BPD and Axis I pathology completed tasks that assessed the degree to which participants incorporated information about valence (pleasant–unpleasant) and arousal (calm–activated) in their semantic/conceptual representations of emotions and in using labels to represent emotional reactions. As hypothesized, participants with BPD emphasized valence more and arousal less than control participants did when using emotion terms to label their emotional reactions. Implications and future research directions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
996.
Representing scientific data sets in KML: Methods and challenges   总被引:2,自引:0,他引:2  
Virtual Globes such as Google Earth and NASA World Wind permit users to explore rich imagery and the topography of the Earth. While other online services such as map servers provide ways to view, query, and download geographic information, the public has become captivated with the ability to view the Earth’s features virtually. The National Snow and Ice Data Center began to display scientific data on Virtual Globes in 2006. The work continues to evolve with the production of high-quality Keyhole Markup Language (KML) representations of scientific data and an assortment of technical experiments. KML files are interoperable with many Virtual Globe or mapping software packages. This paper discusses the science benefits of Virtual Globes, summarizes KML creation methods, and introduces a guide for selecting tools and methods for authoring KML for use with scientific data sets.  相似文献   
997.
Objective: The long-term consequences of traumatic brain injury affect millions of Americans, many of whom report using religion and spirituality to cope. Little research, however, has investigated how various elements of the religious and spiritual belief systems affect rehabilitation outcomes. The present study sought to assess the use of specifically defined elements of religion and spirituality as psychosocial resources in a sample of traumatically brain injured adults. Participants: The sample included 88 adults with brain injury from 1 to 20 years post injury and their knowledgeable significant others (SOs). The majority of the participants with brain injury were male (76%), African American (75%) and Christian (76%). Measures: Participants subjectively reported on their religious/spiritual beliefs and psychosocial resources as well as their current physical and psychological status. Significant others reported objective rehabilitation outcomes. Analyses: Hierarchical multiple regression analyses were used to determine the proportion of variance in outcomes accounted for by demographic, injury related, psychosocial and religious/spiritual variables. Results: The results indicate that religious well-being (a sense of connection to a higher power) was a unique predictor for life satisfaction, distress and functional ability whereas public religious practice and existential well-being were not. Conclusions: The findings of this project indicate that specific facets of religious and spiritual belief systems do play direct and unique roles in predicting rehabilitation outcomes whereas religious activity does not. Notably, a self-reported individual connection to a higher power was an extremely robust predictor of both subjective and objective outcome. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
998.
Objective: To evaluate the sensitivity, specificity, and predictive values of Post-Deployment Health Assessment traumatic brain injury (TBI) screening questions employed by the Department of Defense (DOD). Participants: Complete data was obtained from 3,072 soldiers upon return from a 15-month deployment to Iraq. Method: Comparisons were made between responses to the DOD four-item screener and a brief structured clinical interview for likely deployment-related TBI history. The interview process was facilitated using responses to the Warrior Administered Retrospective Casualty Assessment Tool (WARCAT). Results: The sensitivity and specificity of the DOD screening tool (positive response to all four items) in comparison to the clinician-confirmed diagnosis was 60% and 96%, respectively. The sensitivity increased to 80%, with a slight decrease in specificity to 93%, for positive TBI screening when affirmative responses to questions 1 and 2 only were included. Conclusions: Affirmative responses to questions 1 and 2 of the DOD TBI screening tool demonstrated higher sensitivity for clinician-diagnosed deployment-related TBI. These two items perform better than positive responses to all four questions; the criteria presently being used for documentation and referral of a deployment-related TBI. These findings support further exploration of TBI screening and assessment procedures. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
999.
The authors measured event-related potentials with a craving manipulation to investigate the neural correlates of drug cue reactivity in 13 adolescents who are cannabis dependent (CD; ages 14–17). The P300 responses to marijuana (MJ) pictures (MJ-P300) and control pictures (C-P300) were assessed after handling neutral objects and again after handling MJ paraphernalia (MJP). Self-reported drug craving and heart rates also were measured. MJ-P300 were larger than C-P300 (p p = .002 and p = .003, respectively), with no association between the magnitude of craving and MJ-P300. Heart rates were not affected by handling MJP. The results showed that adolescents who are CD have an attentional bias to MJ stimuli that increases after handling marijuana paraphernalia. Generally, the results are consistent with what has been reported for adult heavy chronic cannabis smokers, although there were some differences that require further investigation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
1000.
Objective: The current study evaluates the long-term psychological impact of a decision aid intervention for surgical and systemic treatment in women with newly diagnosed breast cancer from a previous reported randomized, controlled trial (Vodermaier et al., 2009). Methods: Patients (n = 111) were randomized into usual care, or a 20-min decision aid intervention plus an information brochure prior to consultation planning with the senior physician. The retention rate at 1 year was 88%. Results: Linear mixed model analyses demonstrated that the intervention group experienced less decisional conflict (p = .047; d = .19), which was driven by perceptions of a more effective choice (p = .029; d = .20) over time. Subgroup analyses revealed that patients in the intervention group who participated in chemotherapy decision making showed better long-term body image outcomes (p = .009; d = .44), which were mediated by reduced depressive coping (p = .049). No effects emerged for anxiety and depressive symptoms, or for quality of life. Internal health locus of control moderated group effects on 'uncertainty with the decision' (p = .003). Conclusions: The study results provide novel evidence on the role of individual differences and the mechanisms behind decision aid effectiveness, and demonstrate the long-term impact of decision aid interventions on some indices of well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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