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991.
Scott C. Ellis Thomas J. Goldsby Ana M. Bailey Jae‐Young Oh 《Decision Sciences Journal of Innovative Education》2014,12(4):287-319
Lean six sigma is a management methodology that firms can employ to achieve substantial improvement in supply chain performance. However, few pedagogical exercises facilitate students’ use of a comprehensive set of lean six sigma principles within a supply chain context. We describe the Airplane Supply Chain Simulation that helps students understand how lean six sigma concepts may be leveraged to improve supply chain performance. The basis of this simulation is a four‐tier supply chain, consisting of suppliers (two tiers), a manufacturer, and a customer, that produces three models of paper airplanes to meet randomly distributed customer demand. In the first of three successive runs, a highly structured simulation is executed in which supply chain roles are well defined, material flows are convoluted, and a “push” production strategy is followed. The first simulation as the “current state” and, for the second and third simulation runs, challenge competing student teams to leverage lean six sigma concepts to develop a “future state” that enables the fulfillment of all customer orders at the lowest cost. Results based on statistical analyses of survey response data from 194 MBA students show that the Airplane Supply Chain Simulation is an effective participative, team‐based learning tool. 相似文献
992.
Elizabeth A. van Es Judith Haymore Sandholtz Lauren M. Shea 《Peabody Journal of Education》2014,89(4):482-499
The study compared candidates in a 4-year undergraduate program for secondary mathematics and science teaching, based on the UTeach model, with candidates in a 1-year postbaccalaureate program at the same institution. Candidates in the undergraduate program participated in a partnership of university mathematics, science, and education departments and intensive field-based experiences in high-needs schools. We conjectured that this approach would better prepare prospective teachers to develop beginning teacher competencies. Analysis of the Performance Assessment for California Teachers Teaching Event identified few differences between candidates in both groups. Surveys revealed significant differences between candidates’ perceptions of their preparation for teaching. These findings suggest that different program models can offer differential support to prospective teachers but how the program features are enacted influences the impact that these programs have on teacher preparation. 相似文献
993.
Comprehension tests often compare accuracy on inferential versus literal questions and find inferential harder than literal, and poor comprehenders performing worse than controls. Difficulties in integration are assumed to be the reason. This research explores another reason—differences in memory for the passage information underlying the questions. Thirty-nine poor comprehenders and 39 controls were given multiple-paragraph passages, which they retold before answering questions. Retellings permitted assessing question accuracy as a function of memory for the text underlying each question. Inferential accuracy was poorer than literal, and the expected group effect was obtained. However, when text memory was perfect, group differences disappeared, indicating that poor comprehenders can generate inferences as well as controls, if they have the relevant information in memory. These findings show that text memory is crucial in distinguishing poor comprehension. 相似文献
994.
Nicole Cushman Leslie M. Kantor Elizabeth Schroeder Lesley Eicher Gina Gambone 《Sex education》2014,14(5):481-496
In this study, we identified 10 sexuality education programmes from different locations in the USA that aim to give young people knowledge and skills to develop healthy relationships, as well as avoid pregnancy and disease. We conducted in-depth interviews with programme administrators to develop a series of case studies and provide concrete recommendations for education and public health professionals to implement similar approaches in their communities. Many programme administrators succeeded in developing partnerships, adapting existing curricula to suit their environments, engaging external evaluators and garnering support from teachers and parents. However, few programme developers conducted formal needs assessments before developing programmes and many struggled to implement curricula with fidelity and to employ rigorous evaluation designs. Nearly all participants identified concerns over funding as a threat to sustainability. We conclude that schools and organisations need technical assistance to build capacity for rigorous programme planning, implementation and evaluation, as well as additional funding streams to support emerging programmes. 相似文献
995.
996.
We demonstrate the method of non-inertial lift induced cell sorting (NILICS), a continuous, passive, and label-free cell sorting approach in a simple single layer microfluidic device at low Reynolds number flow conditions. In the experiments, we exploit the non-inertial lift effect to sort circulating MV3-melanoma cells from red blood cell suspensions at different hematocrits as high as 9%. We analyze the separation process and the influence of hematocrit and volume flow rates. We achieve sorting efficiencies for MV3-cells up to EMV3 = 100% at Hct = 9% and demonstrate cell viability by recultivation of the sorted cells. 相似文献
997.
D. Puri K. M. Prabhu G. Dev S. Agarwal P. S. Murthy 《Indian journal of clinical biochemistry : IJCB》2011,26(4):335-346
To study the mechanism of action of water soluble compound GII purified from fenugreek (Trigonella foenum graecum) seeds which was shown earlier to have antidiabetic effect in the subdiabetic, moderately and severely diabetic rabbits.
In rabbits (1–1.5 kg bw) diabetes was induced by intravenous injection of 80 mg/kg bw of alloxan. They were fed with GII at
a dose of 50 mg/kg bw daily once in the morning for 15 days in the subdiabetic and moderately diabetic and 30 days in the
severely diabetic rabbits. Serum total cholesterol (TC), triglycerides (TG), LDL + VLDL cholesterol [(LDL + VLDL)C], HDL cholesterol
[(HDL)C], total tissue lipids, glycogen and enzymes of carbohydrate metabolism (glycolysis, gluconeogenesis, polyol pathway)
hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, aldose reductase
and sorbitol dehydrogenase and antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase
were estimated. Liver and kidney function parameters were also estimated. Treatment with GII for 15 days in the subdiabetic
and moderately diabetic rabbits and for 30 days in the severely diabetic rabbits (i) decreased the elevated lipids TC, TG,
(LDL + VLDL)C and increased the decreased (HDL)C, (ii) decreased the elevated liver and heart total lipids, TC and TG, (iii)
increased the decreased liver and muscle glycogen, (iv) increased the decreased hexokinase, glucokinase, pyruvate kinase,
malic enzyme, glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione peroxidase, (v) decreased the increased
glucose-6-phosphatase, sorbitol dehydrogenase, aldose reductase. Results thus show that treatment with GII compound purified
from fenugreek seeds for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits corrects
the altered serum lipids, tissue lipids, glycogen, enzymes of glycolysis, gluconeogenesis, glycogen metabolism, polyol pathway
and antioxidant enzymes. Histopathological abnormalities (fatty infiltration and other cellular changes) seen in the pancreas,
liver, heart and kidneys were repaired after treatment with GII. In fact partially damaged pancreas was repaired. Liver and
kidney function test results were normal in the GII treated animals indicating that GII treatment is safe and free from any
side effects. 相似文献
998.
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method. 相似文献
999.
This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. The proposed controller is designed based on strict-positive-real (SPR) Lyapunov stability theory to ensure the asymptotic stability of the closed-loop system. Finally, two simulation studies are presented to demonstrate the effectiveness of the developed scheme. 相似文献
1000.