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Lilith R. Kunkel Library Director Susan M. Weaver Library Director Kim N. Cook Library Director 《The Journal of Academic Librarianship》1996,22(6):430-434
This article, which examines variables affecting scores on a test of library skills, finds that the frequency with which students receive assignments requiring library research is the best predictor of a score. The unevenness is students' research skills has implications for bibliographic instruction. 相似文献
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Amit Asthana Kwang Ho Lee Kyeong-Ohn Kim Dong-Myung Kim Dong-Pyo Kim 《Biomicrofluidics》2012,6(1):012821-012821-9
In this paper, we have presented a non-lithographic embedded template method for rapid and cost-effective fabrication of a selectively permeable calcium-alginate (Ca-alginate) based microfluidic device with long serpentine delay channel. To demonstrate the versatility of the presented method, we have demonstrated two different strategies to fabricate serpentine long delay channels without using any sophisticated microfabrication techniques, in formal lab atmosphere. The procedure presented here, also, enables the preparation of a multilayered microfluidic device with channels of varying dimensions, in a single device without using any sophisticated micromachining instrumentation. In addition, we have also qualitatively studied the diffusion of small and large molecules from a Ca-alginate based microfluidic device and proposed a method to effectively control the out-flow of macro biomolecules from the crosslinked Ca-alginate matrix to create a selectively permeable matrix required for various biological and biomimetic applications, as mentioned in the Introduction section of this work. 相似文献
126.
A spacecraft formation flying controller is designed using a sliding mode control scheme with the adaptive gain and neural networks. Six-degree-of-freedom spacecraft nonlinear dynamic model is considered, and a leader–follower approach is adopted for efficient spacecraft formation flying. Uncertainties and external disturbances have effects on controlling the relative position and attitude of the spacecrafts in the formation. The main benefit of the sliding mode control is the robust stability of the closed-loop system. To improve the performance of the sliding mode control, an adaptive controller based on neural networks is used to compensate for the effects of the modeling error, external disturbance, and nonlinearities. The stability analysis of the closed-loop system is performed using the Lyapunov stability theorem. A spacecraft model with 12 thrusts as actuators is considered for controlling the relative position and attitude of the follower spacecraft. Numerical simulation results are presented to show the effectiveness of the proposed controller. 相似文献
127.
Woo Taek Kim Sung Gyun Ahn Jun-Won Lee Joong Kyung Sung Seung Hwan Lee Junghan Yoon 《Journal of Zhejiang University. Science. B》2010,11(8):627-630
It is a challenge to confirm chronic mesenteric ischemia (CMI) as a cause of gastrointestinal (Gl) symptoms such as postprandial epigastric bloating,anorexia,and debilitating weight loss.Endovascular intervention for CMI has been gaining popularity because of the high morbidity associated with surgical revascularization.However,in EVI for superior mesenteric artery (SMA) occlusion,the transfemoral approach is limited by difficulty in coaxial alignment of the guiding catheter,which leads to insufficient back-up support.Herein,we report on a 58-year-old male patient with chronic total occlusion of the SMA,which was successfully revascularized by endovascular intervention via the left radial artery.Transradial endovascutar therapy may be another treatment option for the treatment of CMI. 相似文献
128.
This study discusses a yard planning system,which considers various resources such as storage space,yard cranes,and traffic areas in container terminals.The system is based on the function for estimating resource requirements of yard plans.For a given yard plan,the proposed system allows planners to check the feasibility of the plan which requires a certain amount of workload of resources in related blocks during a planning horizon.The yard planning system in this study is aimed at balancing workloads among the blocks and providing the ability to modify current yard plans by detecting blocks and periods with overloaded workloads.The system implements its planning function in a distributed manner in which planners construct yard plans under their individual control and send and receive only limited necessary information for the negotiation. 相似文献
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Burgess KB Wojslawowicz JC Rubin KH Rose-Krasnor L Booth-LaForce C 《Child development》2006,77(2):371-383
The primary objectives of this investigation were to examine the attributions, emotional reactions, and coping strategies of shy/withdrawn and aggressive girls and boys and to examine whether such social cognitions differ within the relationship context of friendship. Drawn from a sample of fifth and sixth graders (M age = 10.79 years; SD = .77), 78 shy/withdrawn, 76 aggressive, and 85 control children were presented with hypothetical social situations that first involved unfamiliar peers, and then a mutual good friend. Results revealed group and gender differences and similarities, depending on the relationship context. From our findings emerges a central message: friends' involvement during interpersonal challenges or stressors mitigates children's attributions, emotions, and coping responses. 相似文献
130.
Veerle Hulpiau Evelien Masschelein Luc Van Der Stockt Piet Verhesschen Kim Waeytens 《Tertiary Education and Management》2013,19(1):35-45
As a consequence of the suspension of a system of yearly evaluations of individual courses with student questionnaires, the University of Leuven organised a broad consultation of the academic community focussing on what they expect from a system based on student feedback. The study revealed that this community attaches great importance to a clear definition of the goals of student feedback, improvement and accountability, and a logical translation of these goals into a concrete approach. The study also confirmed the need of academic staff for a concrete response to the importance they give to quality improvement and enhancement besides accountability. 相似文献