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91.
在认知无线电网络中,主用户使用授权频段时认知用户需要避让。这将导致认知用户原路由上工作频率的频繁切换。为了尽量减少这种切换,维持原路由上数据持续高效地传输,提出了一种优化的认知无线网络路由维护方案。在认知无线网络中,当认知用户测得主用户存在时先测试主用户的运动速度、运动方向等信息,继而根据主用户实际的运动情况判断认知用户是否可以避让。仿真结果显示,认知用户通过有效的避让既避免了对主用户的干扰,又维持了认知网络原路由继续工作。  相似文献   
92.
Emotional Stroop tasks (subliminal/supraliminal exposures), implicit memory tasks (tachistoscopic word identification), and explicit memory tasks (free recall after incidental learning) with 4 word types (physical threat, positive, negative, and neutral words) were administered to patients with major depressive disorder (n = 30), panic disorder (n = 33), somatoform disorder (n = 25), and healthy control participants (n = 33). On the Stroop task, panic patients showed subliminal interferences for physical threat and negative words, depressive patients showed supraliminal interferences for negative words, and somatoform patients showed supraliminal interferences for physical threat words. No patient groups demonstrated implicit memory biases. On the explicit memory task, depressive and panic patients showed memory biases for negative words; somatoform patients showed biases for physical threat words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
In the present study, the authors examined somatosensory processing in 30 biological relatives of persons with schizophrenia (hereafter called "schizophrenia relatives"), 30 biological relatives of persons with bipolar affective disorder (psychiatric family control subjects), and 30 healthy control subjects with no family history of psychopathology. All 3 groups completed a weight discrimination task, a 2-point discrimination task, and a complex cognitive somatosensory task (i.e., graphesthesia). The schizophrenia relatives performed significantly worse on all 3 somatosensory tasks compared with both the healthy control subjects and the bipolar relatives. The healthy control subjects and psychiatric family control subjects showed no significant differences on any of the somatosensory tasks. Within the weight discrimination and 2-point discrimination tasks, schizophrenia relatives showed group differences on the d' index, the measure of sensitivity, whereas all 3 groups did not differ on lnβ, the measure of response bias, suggesting a genuine difference in weight and touch sensitivity. The d' value of the weight discrimination task was significantly associated with both the cognitive-perceptual factor and negative symptom factor of the clinical questionnaire (e.g., Schizotypal Personality Questionnaire; SPQ), whereas the 2-point discrimination d' value and graphesthesia scores were significantly associated only with the cognitive-perceptual factor of the SPQ. Implications for the possible relation between somatosensory task performance and schizophrenia liability are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
Review of book The Robot's Rebellion: Finding Meaning in the Age of Darwin by Keith E. Stanovich (see record 2004-95228-000). In his interesting scholarly book, The Robot's Rebellion, Stanovich leads us on a journey to find meaning in a world populated by mortal biological vehicles, the robots, put on earth to replicate their masters' selfish genes. If the genes do a satisfactory job programming the robots, then the genes replicate in perpetuity and are, therefore, immortal. Stanovich's basic assumptions are: a) vehicles are designed to replicate genes; b) at least in human animals, the brain houses two minds; c) the first mind, System 1 or The Autonomous Set of Systems, evolved much earlier in evolutionary history than did the second mind, System 2 or the Analytic System; d) System 1 is associative, parallel, fast to respond, and designed to automatically serve its genetic master; e) System 2 is rule-based, serial, slow to respond, not aware of System 1 functioning but sometimes privy to System 1 output, controls executive functioning, and is capable of self-evaluation and leading the rebellion against its genetic master; and, f) memes, culturally generated ideas passed on by nongenetic means, can sometimes be as effective as System 1 at squashing the rebellion. These assumptions are derived from work in cognitive science and evolutionary biology, and provide a solid foundation for the book. Both the metaphor and the basic assumptions are embedded in detailed and informative reviews of decision theory, evolutionary psychology, memetic theory, rational philosophy, and utility theory. The interweaving of metaphor and review provides a framework that allows Stanovich to make inferences to help the general reader understand "the implications of modern science" (p. xi). He also develops criteria to evaluate memes that are needed in his quest to find meaning in human existence. In combination with the basic assumptions, these criteria are used to create an ethical ideology that will be embraced by some readers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Halfway through a 3-hour experiment in which 64 3-person teams needed to make a series of decisions, a communications channel began to deteriorate, and teams needed to adapt their system of roles in order to perform effectively. Consistent with previous research, team composition with respect to members' cognitive ability was positively associated with adaptation. Adaptation was also influenced by interactions of team goal difficulty and team composition with respect to team members' goal orientation. Teams with difficult goals and staffed with high-performance orientation members were especially unlikely to adapt. Teams with difficult goals and staffed with high-learning orientation members were especially likely to adapt. Supplemental analyses provided insight into the observed effects in that the difficulty of team goals and members' goal orientation predicted interpersonal, transition, and action processes, all of which predicted team adaptation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Sexually dimorphic cognitive performance in men (n=42) and women (n=42) was related to testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin, measured in 10-ml blood samples collected between 0900 and 1030 and, among women, during the follicular phase of the menstrual cycle. Significant sex differences favored men on spatial tasks (Mental Rotation and Judgment of Line Orientation) and on an inhibition task and favored women on a verbal task (category fluency). However, there were no significant relationships between any of the hormones and cognitive performance, suggesting that there are few, if any, consistent, substantial relationships between endogenous, nonfluctuating levels of gonadal hormones or gonadotropins and these cognitive abilities in men or women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
The authors explored the prognostic value of 3 different types of catastrophic cognitions in the treatment of panic disorder with and without mild-to-moderate agoraphobia using a sample of 143 participants who received either cognitive-behavioral therapy (CBT) or imipramine in a randomized controlled trial. Stronger fears of social catastrophes both prior to and following treatment with CBT or imipramine were associated with a poorer outcome. In contrast, cognitions involving physical or mental catastrophes were unrelated to outcome, regardless of whether these thoughts were measured prior to or following treatment. These findings are consistent with the notion that although the intensity of physical catastrophe cognitions may best discriminate between panic disorder and other anxiety disorders, it is the intensity of social catastrophe cognitions that is most closely tied to success in treating this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
The relationship between treatment outcome and the extent to which participants completed homework assignments was evaluated among 60 cocaine-dependent individuals assigned to cognitive-behavioral therapy (CBT). Homework was assigned in 72% of all sessions and initiated by participants in 48% of the sessions in which it was assigned. Completion of homework was unrelated to participants' baseline characteristics and several indicators of treatment compliance. Participants who completed more homework assignments demonstrated significantly greater increases in the quantity and quality of their coping skills and used significantly less cocaine during treatment and through a 1-year follow-up. These data suggest that the extent to which participants are willing to complete extrasession assignments may be an important mediator of response to CBT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
The authors of this study examined the outcomes and processes of 2 types of group treatment--cognitive-behavioral treatment groups (CBTG) and humanistic group therapy (HGT)--offered to 200 elementary schoolchildren in a center for students with learning disabilities in Israel. Results indicated that the addition of either type of group treatment to individual academic assistance was more effective than the latter alone on most measures. In fact, on the majority of measures, group treatment without academic assistance was more effective than just individual assistance. Finally, HGT was more effective than CBTG on most measures. Most of the outcomes were sustained at follow-up, and some even increased from termination to follow-up, although effect sizes were quite low. Process measures included the Client Behavior System and the therapist Helping Skills System, which were measured at 5 points in time. Differences between the 2 treatment types were revealed on both process measures, including differences in the growth curve of these behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
This study adds to the growing literature linking children's experiences in the environment to individual differences in their developing skills in attention, memory, and planning. The authors asked about the extent to which stimulating and sensitive care in the family and in the child-care or school environments would predict these cognitive outcomes. The authors also questioned the primacy of experiences in the first 3 years of life. Data from a sample of 700 first graders whose experiences in the home and in child care or school were evaluated since early infancy revealed that the cumulative quality of the child-rearing environment was related to attention and memory but not to planning and that the quality of the family environment was more strongly associated with outcomes than was the quality of child care and of school. The quality of both children's early (6 through 36 months) and later (54 months and first grade) environments predicted performance on the attention and memory tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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