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991.
Jong-Duk Son Gang Niu Bo-Suk Yang Don-Ha Hwang Dong-Sik Kang 《Expert systems with applications》2009,36(9):11981-11991
Machine fault diagnosis is a traditional maintenance problem. In the past, the maintenance using tradition sensors is money-cost, which limits wide application in industry. To develop a cost-effective maintenance technique, this paper presents a novel research using smart sensor systems for machine fault diagnosis. In this paper, a smart sensors system is developed which acquires three types of signals involving vibration, current, and flux from induction motors. And then, support vector machine, linear discriminant analysis, k-nearest neighbors, and random forests algorithm are employed as classifiers for fault diagnosis. The parameters of these classifiers are optimized by using cross-validation method. The experimental results show that smart sensor system has the similar performance for applying in intelligent machine fault diagnosis with reduced product cost. Developed smart sensors have feasibility to apply for intelligent fault diagnosis. 相似文献
992.
993.
Sangwon Kang Changyong Son Hosang Sung 《Communications Letters, IEEE》2001,5(5):212-214
A fast-search method is introduced to reduce the searching range of a codebook using the ordering property of LSF parameters. We apply the proposed fast-search method to the G.723.1 coder with the predictive split VQ structure. Simulation results indicate that using this fast-search method, the average searching range of the codebook can be reduced by 20.1% without degradation of the spectral distortion (SD) and additional increases of memories. The reduction of 20.1% in the average searching range results in the decrease of 19.1%, 20.1%, 19.4%, and 12.2% in the number of additions, subtractions, multiplies, and comparisons, respectively 相似文献
994.
995.
The importance of English Medium Instruction (EMI) has greatly increased in non-English speaking countries, including Korea, due to the trend of globalization. Nonetheless, the effectiveness of EMI has been questioned in most of the universities in Korea where EMI has been rapidly adopted. This paper explores the optimal design of EMI in order to maximize students’ achievement. Additionally, regression analysis and choice simulation based on scenario analysis are used to suggest more effective EMI programs. 相似文献
996.
997.
998.
SB Han HM Kim YH Kim CW Lee ES Jang KH Son SU Kim YK Kim 《Canadian Metallurgical Quarterly》1998,20(1-3):1-13
One of the characteristics of obesity-associated diabetes is an elevated fasting plasma insulin concentration with a weak insulin secretory response to subsequent glucose stimulation. Evidence suggests that hyperglycemia and hyperlipidemia may contribute to the initiation and progression of this disordered islet glucose sensing. It has been proposed that reducing hyperglycemia and hyperlipidemia per se may improve islet glucose sensing. Here we studied glucose-dependent insulin release in islets isolated from ob/ob mice treated with dopamine agonists (bromocriptine and SKF38393, BC/SKF) which significantly reduced circulating glucose and lipid levels of ob/ob mice. Islets from BC/SKF-treated mice showed a marked decrease of the elevated basal insulin release to levels similar to lean mice. Such treatment also induced a higher secretory response to glucose stimulation compared with that in ob/ob mice with sustained hyperglycemia and hyperlipidemia. Similarly, when islets from untreated ob/ob mice were cultured for 7 days in 11 mM glucose in the absence of free fatty acid, the basal insulin release was significantly decreased and high glucose stimulated insulin release increased compared with that from islets cultured in medium containing 30 mM glucose and 2 mM oleate. The BC/SKF-induced reduction of elevated basal insulin release was associated with decreased hexokinase activity and basal cyclic AMP content in islet tissue. Our results demonstrate that dopamine agonist treatment improves basal insulin release in ob/ob mice and this effect may be mediated, in part, by a reduction of hyperglycemia and hyperlipidemia. 相似文献
999.
研究在醋酸、蚁酸和柠檬酸的条件下利用染料的酸性隐色体的形式来染色的技术。同时研究了尿素的加入对提高染料上染的作用。除此之外,对靛蓝染料染色后的样品进行反复多次清洗,并与分散染料的染色样品相比较,以此测试牢度性能。 相似文献
1000.
B. R. Kim J. W. Kang K. Y. Lee J. M. Son M. J. Ko 《Journal of Materials Science》2007,42(12):4591-4602
Though spin-on organosilicates are considered as the promising candidates of low dielectric constant materials, it is necessary
for a successful integration to improve mechanical strength such as modulus and fracture toughness. In this study, five sets
of MTMS–BTMSE copolymers were synthesized and characterized while the monomer content of BTMSE (bis(trimethoxysilyl)ethane)
was varied from 9.1 to 47.3 mol% vs. MTMS (methyltrimethoxysilane). In parallel with the measurement of dielectric constant,
four different tests were carried out to evaluate mechanical properties of the MTMS–BTMSE copolymers. Modulus was measured
by the nanoindentation technique and the modified edge lift-off test (MELT) was employed to extract adhesive fracture toughness
quantitatively. In addition, residual stress was calculated by sensing the change in radius of curvature of the substrate.
The chemical structure of the copolymers was also analyzed with FTIR and NMR. Network formation was enhanced as the amount
of BTMSE increased, which led to improvement of modulus and the increase in refractive index and dielectric constant. However,
an increasing rate of fracture toughness by the MELT was not proportional to the increase in the amount of BTMSE, which implied
that it was necessary to optimize the composition of the copolymers since adhesion strength was conjectured the most critical
factor for a successful integration. 相似文献