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991.
We propose and study exponentially weighted moving average (EWMA) control charts for monitoring high-yield processes. The EWMA control charts are developed based on non-transformed geometric, binomial and Bernoulli counts. The proposed charts are evaluated based on the average number of items sampled before the first out-of-control signal is detected. By selecting small smoothing constants, the proposed EWMA control charts outperform in numerous cases the recently developed CUSUM control charts [Chang, T.C. and Gan, F.F., Cumulative sum charts for high yield processes. Statist. Sin., 2001, 11, 791–805], which are considered the most efficient control charting mechanisms in the existing literature for monitoring fraction non-conforming as small as 0.0001. Numerous simulations are included for performance comparisons. An example is also given to demonstrate the applicability of the proposed EWMA control charts. 相似文献
992.
This study considers a supply chain consisting of a manufacturer, a retailer, customers and a returnable and modular product with uncertain demand, in which customers return the unsatisfactory products to the retailer, and the retailer returns the unsold products to the manufacturer. We investigate the effects of the manufacturer’s refund for the retailer’s unsold products and the product modularity under the decentralised and the centralised strategies. We confirm that the order quantity and customer’s return probability both affect the optimal modularity level of the product, and that the optimal modularity level is related to the refund policy. Also, a strategic alliance between the supply chain members is more advantageous to product innovation based on modularity for a returnable chain. Finally, managerial insights and remarks are offered. 相似文献
993.
A dust explosion is triggered by the rapid combustion of burnable particulate matter suspended in air. Two blank tests and three Ag-dust-cloud explosion tests were performed in a 20-L spherical steel chamber using a 5 kJ pyrotechnic igniter as the energy source in each test. In the explosion tests, no apparent increase in pressure above that found in the blank tests was observed for Ag dust cloud with a concentration of 0.8 g/L. In addition, fine solid particles remaining after the tests showed no evidence of a combustion reaction at the end of the tests. In this research, the thermal decomposition of Ag powders was measured using a differential scanning calorimeter, and the thermal analysis technique to estimate hazards in relation to the samples was employed. The change in enthalpies (H) of the Ag powders were approximately 180, 93, and 53 J/g, and the onset temperatures (T0) were approximately 211.76, 201.41, and 240.46 °C for P3032, P3012, and P3072, respectively. These results support the conclusion that Ag samples with concentrations below 0.8 g/L do not pose a dust explosion hazard. 相似文献
994.
Optimizations of sewer network designs create complicated and highly nonlinear problems wherein conventional optimization techniques often get easily bogged down in local optima and cannot successfully address such problems. In the past decades, heuristic algorithms possessing robust and efficient global search capabilities have helped to solve continuous and discrete optimization problems and have demonstrated considerable promise. This study applied tabu search (TS) and simulated annealing (SA) to the optimization of sewer network designs. For a case study, this article used the sewer network design of a central Taiwan township, which contains significantly varied elevations, and the optimal designs from TS and SA were compared with the original official design. The results show that, in contrast with the original design's failure to satisfy the minimum flow-velocity requirements, both TS and SA achieved least-cost solutions that also fulfilled all the constraints of the design criteria. According to the average performance of 200 trials, SA outperformed TS in both robustness and efficiency for solving sewer network optimization problems. 相似文献
995.
Jen-Taut Yeh Ching-Ju Wu Chi-Hui Tsou Wan-Lan Chai Jing-Dong Chow Chi-Yuan Huang 《Polymer-Plastics Technology and Engineering》2013,52(6):571-578
A series of blends of poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL) with different mass ratio were prepared by means of the melt blending method to study their crystallization, miscibility, morphology, and thermal and mechanical properties. The result of DSC tests showed that the melting temperatures of PLA and PCL shifted toward each other, and that the largest shift appeared at the PLA70PCL30 blend. This result reveals that the PLA70PCL30 blend gives the strongest interaction intensity among the blends. Combined the result of dynamic mechanical analysis and SEM morphologies, it was found that PLA and PCL form a partial miscible blend, in which an amount of amorphous PCL (amorphous PLA) is dissolved in the PLA-rich phase (PCL-rich phase), leading to a depression of the Tg. value. The polarized optical micrographs showed that PCL can serve as a nucleating agent to promote PLA crystallization in the PLA/PCL blend. Moreover, the PLA70PCL30 blend gave the largest growth rate of PLA spherulite. Finally, the mechanical property of PLA/PCL blends indicated that PLA can easily be tuned from rigid to ductile by the addition of PCL. 相似文献
996.
Y. S. Yeh T. S. Wu Y T. Lo C. W. Su S. C. Wu 《International Journal of Electronics》2013,100(8):517-532
The fundamental harmonic TE01 gyrotron travelling wave amplifier (gyro-TWT) is a high-power, broadband, millimetre-wave amplifier with a low ohmic dissipation and a large guiding centre radius. However, spurious oscillations may reduce the amplification of the gyro-TWT. The stability of severed and distributed-loss gyro-TWTs is analysed, using a self-consistent simulation code. A nonlinear analysis of typical oscillations, including absolute instability, gyrotron backward oscillation (gyro-BWO) and reflective oscillation, is presented. Simulation results indicate that attenuating severs in the severed gyro-TWT do not suppress spurious oscillations, and that increasing the wall losses to suppress gyro-BWO in the distributed-loss gyro-TWT degrades the efficiency of the gyro-TWT amplifier. A multi-stage distributed-loss gyro-TWT design is developed to stabilize the amplification. The lossy and severed sections of the multi-stage gyro-TWT seem to increase effectively the start-oscillation currents of absolute instability and gyro-BWO, respectively. The multi-stage gyro-TWT is predicted to yield a peak output power of 155?kW at 32.9?GHz with an efficiency of 15%, a saturated gain of 45?dB and a bandwidth of 2.2?GHz for a 100?kV, 10?A electron beam with an axial velocity spread Δvz /vz = 5%. 相似文献
997.
998.
Mu-Shih Yeh Yung-Chun Wu Min-Feng Hung Kuan-Cheng Liu Yi-Ruei Jhan Lun-Chun Chen Chun-Yen Chang 《Nanoscale research letters》2013,8(1):331
This study proposed the twin poly-Si fin field-effect transistor (FinFET) nonvolatile memory with a structure that is composed of Ω-gate nanowires (NWs). Experimental results show that the NW device has superior memory characteristics because its Ω-gate structure provides a large memory window and high program/erase efficiency. With respect to endurance and retention, the memory window can be maintained at 3.5 V after 104 program and erase cycles, and after 10 years, the charge is 47.7% of its initial value. This investigation explores its feasibility in the future active matrix liquid crystal display system-on-panel and three-dimensional stacked flash memory applications. 相似文献
999.
Han-Cheng Yeh Hsin-Fei Meng Hao-Wu Lin Teng-Chih Chao Mei-Rurng Tseng Hsiao-Wen Zan 《Organic Electronics》2012,13(5):914-918
Blue and white small-molecule organic light-emitting diodes are fabricated by multi-layer blade coating on hot plate at 80 °C with hot wind. Uniform multi-layer structures are made without dissolution due to rapid drying. Only small molecules originally developed for vacuum deposition are used. For hole transport layer of, 4′,4″-tris(carbazol-9-yl)triphenylamine (TCTA), electron transport layer of 2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TBPI), emissive layer host of, 6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy), triplet emitters of bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(III) (FIrpic), and cathode of LiF/Al, the peak current efficiency for blue emission is 25.1 cd/A (10.8% and 9.3 lm/W). Orange emitter iridium(III)bis (4-(4-t-butylphenyl) thieno[3,2-c]pyridinato-N,C2′)acetylacetonate (PO-01-TB) is added to obtain white emission with CIE coordinate of (0.39, 0.46) [1]. The current efficiency is 34.2 cd/A (11.6% and 12 lm/W) at maximum, 32.4 cd/A at 1000 cd/m2, and 31 cd/A at 10,000 cd/m2. 相似文献
1000.
Bacillus subtilis is an ideal host for the production of extracellular heterologous proteins. The use of a strong, constitutive promoter is a good means of optimizing the expression of heterologous proteins. In this study, high level extracellular production of subtilisin YaB, a potent meat tenderizer, was achieved by engineering the wild-type subtilisin YaB promoter into an artificial promoter and expressed in Bacillus subtilis host. This artificial promoter provides an efficient tool to produce mutant subtilisin YaB or other recombinant heterologous proteins by B. subtilis at high level. 相似文献