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141.
Young H. Chun 《国际生产研究杂志》2016,54(19):5686-5696
A complex product is often inspected more than once in a sequential manner to ensure the product’s quality. Based on the number of defects discovered during each round of inspection process, we can estimate the number of defects still remaining in the product. For each defect, the probability that the defect will be detected during each inspection cycle is usually assumed to be a known ‘constant’. However, in many practical situations, some defects are easily detected, while others are much more difficult to identify. In this paper, we propose a ‘beta-geometric’ inspection model in which the heterogeneity in detection probability is described by a beta distribution. In a numerical study, we show that our more realistic inspection model clearly outperforms traditional estimation methods that are based on the assumption of a constant detection probability. 相似文献
142.
Na?Young?Kang Seong?Ihl?Woo Yu?Jin?Lee Jongyoon?Bae Won?Choon?Choi Yong-Ki?ParkEmail author 《Journal of Materials Science》2016,51(8):3735-3749
We successfully synthesized hydrothermally stable ZSM-5 with crystalline nano seeds. We employed a template-free method using ZSM-5 crystalline nano seeds and sodium silicate as a silica source. The prepared ZSM-5 exhibited uniform crystal size and relative crystallinity greater than 100 %. The size of the crystalline nano seed in the scale of 100 nm was found to be the optimum size for obtaining uniform, highly crystalline ZSM-5 with structural stability. After P-modification, the synthesized ZSM-5 with the optimally sized seed showed high hydrothermal stability and improved catalytic naphtha cracking activity compared to a commercial ZSM-5 catalyst. In order to find the elements for the increased hydrothermal stability, the samples were evaluated by studying crystallinity, aluminum spectrum, and acidity using XRD, solid-state NMR, and NH3-TPD, respectively after steaming at 800 °C for 24 h. It is speculated that the increased hydrothermal stability of the ZSM-5 resulted mainly from the increased aluminum structural stability. 相似文献
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Ferroelectrically Gated Atomically Thin Transition‐Metal Dichalcogenides as Nonvolatile Memory 下载免费PDF全文
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Gate‐Tunable Hole and Electron Carrier Transport in Atomically Thin Dual‐Channel WSe2/MoS2 Heterostructure for Ambipolar Field‐Effect Transistors 下载免费PDF全文
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Kyung Seob Lim Jun-Kyu Park Myung Ho Jeong Jae-Woon Nah Dae Sung Park Jong Min Kim Jung Ha Kim So Youn Lee Eun Jae Jang Suyoung Jang Hyun Kuk Kim Doo Sun Sim Keun-Ho Park Young Joon Hong Youngkeun Ahn Jung Chaee Kang 《Journal of materials science. Materials in medicine》2016,27(4):66
The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia. 相似文献
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