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Exchange‐based communication training may not consistently facilitate communication in the absence of the requested item 下载免费PDF全文
The role of stimulus presence on spontaneous communication was assessed with 3 participants in a nonconcurrent multiple baseline with embedded reversals design. Participants were taught to request 2 highly preferred items. Once mastery criterion was met, test sessions were conducted with stimuli either visible or absent from the room, and request rate was measured. For 2 participants, training produced requests in both the presence and absence of the stimulus. For one participant, however, the presence of the stimulus was necessary to evoke the response. Results suggest that teaching individuals to request items when they are present may not consistently lead to requests when those items are absent. 相似文献
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On rough terrain, excessive wheel slippage is easily generated by changes of surface conditions such as soil types and geometries. It induces considerable loss of wheel traction and battery energy. To prevent this, wheeled robots should consistently recognize the current situation generated between wheel and surface. And also wheeled robots are required to optimally control wheel motion in limited wheel traction and battery capacity. Therefore, this paper proposes a novel wheel control algorithm based on slip optimization of traction and energy, which is adaptive to change of surface condition. Proposed wheel control algorithm is called Traction-Energy Balancing Adaptive Control (TEB) in this paper and TEB assigns optimized rotation speed to each wheel by observing wheel slip ratio which is a key parameter of TEB. As functions of TEB, TEB is largely divided into three main parts; (1) slip optimizer (2) slip controller (3) SC-compensator. In the slip optimizer, two optimal slip models were derived as a function of slip ratios regarding maximum traction and tractive efficiency using experimental data about wheel-terrain interaction in three types of soil (grass, gravel and sand). And the optimal slip models were employed in order to determine a desired slip value of wheel with observation of a change in actual robot velocity as control input in the slip controller. For optimal slip control, the proposed slip controller is based on conventional PID controller with compensating disturbance in the controller (SC-compensator) which occurs by change of surface shapes. In the SC-compensator, radial function networks (RBFN) was applied in the slip controller and RBFN was of help to readjust previously set PID gains depending on occurred slip error. Finally, TEB was experimentally verified by controlling a real robot having four wheels on various terrain types. 相似文献
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Background and objectives: Developmental theorists posit that temperament contributes to preadolescent’s stress response styles. Findings from empirical studies, however, have yielded mixed results, thus indicating a need to consider moderators of this relation. Utilizing an analytic framework guided by resiliency theory [Zimmerman, M. A. (2013). Resiliency theory: A strengths-based approach to research and practice for adolescent health. Health Education &; Behavior, 40, 381–383], this study examined achievement goal orientation as a moderator of the relation between temperament and stress response styles.Methods: 96 preadolescent–parent dyads (Mage?=?10.30 years, range?=?9–12 years) participated in the study. Preadolescents reported on their achievement goal orientation, coping and involuntary stress responses (ISRs) styles and a parent reported on children’s temperament.Results: Multiple regressions revealed that effortful control positively predicted preadolescent’s predominant use of engagement coping and negatively predicted predominance of ISRs, but only for children with a predominant mastery goal orientation. For preadolescents with a predominant performance goal orientation, effortful control negatively predicted the predominant use of engagement coping and positively predicted predominance of ISRs. Negative affectivity and its interaction with goal orientation did not predict coping or ISR styles.Conclusions: Findings suggest that a predominant mastery goal orientation may function as a promotive factor by enhancing the contribution of effortful control to engagement coping styles and buffering against unmanaged reactivity. 相似文献
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This study identified the level of trunk control of healthy term infants aged from six to nine months. This cross-sectional study included fifty-five infants aged from six to nine months. The levels of trunk control was investigated by using the Segmental Assessment Trunk Control (SATCo). The infants remained seated on a wooden bench and a neutral pelvic position was maintained. The SATCo score was considered as dependent variable. The results showed that infants aged six and seven months presented levels of trunk control in the thoracic region while infants aged from eight to nine months presented full trunk control. These results demonstrate that younger infants present less levels of trunk control while older infants present full trunk control, confirming that trunk control development takes place in a segmental way and in a cephalocaudal direction. These results also might be used as a reference to distinguish infants that show a delay in trunk control from those who have suitable motor development and, thus intervene at an early stage to minimize later delays in these infantś global motor development. 相似文献
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Calming an aggressor through spontaneous post‐conflict triadic contacts: Appeasement in Macaca tonkeana 下载免费PDF全文