• 제목/요약/키워드: Product Release

검색결과 394건 처리시간 0.021초

Determination of escape rate coefficients of fission products from the defective fuel rod with large defects in PWR

  • Pengtao Fu
    • Nuclear Engineering and Technology
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    • 제55권8호
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    • pp.2977-2983
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    • 2023
  • During normal operation, some parts of the fission product in the defective fuel rods can release into the primary loops in PWR and the escape rate coefficients are widely used to assess quantitatively the release behaviors of fission products in the industry. The escape rate coefficients have been standardized and have been validated by some drilling experiments before the 1970s. In the paper, the model to determine the escape rate coefficients of fission products has been established and the typical escape rate coefficients of noble gas and iodine have been deduced based on the measured radiochemical data in one operating PWR. The result shows that the apparent escape rate coefficients vary with the release-to-birth and decay constants for different fission products of the same element. In addition, it is found that the escape rate coefficients from the defective rod with large defects are much higher than the standard escape rate coefficients, i.e., averagely 4.4 times and 1.8 times for noble gas and iodine respectively. The enhanced release of fission products from the severe secondary hydriding of several defective fuel rods in one cycle may lead to the potential risk of the temporary shutdown of the operating reactors.

반도체 팹에서의 투입 로트 구성을 위한 다차원 동적계획 알고리듬 (Multi-Dimensional Dynamic Programming Algorithm for Input Lot Formation in a Semiconductor Wafer Fabrication Facility)

  • 방준영;임승길;김재곤
    • 산업경영시스템학회지
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    • 제39권1호
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    • pp.73-80
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    • 2016
  • This study focuses on the formation of input release lots in a semiconductor wafer fabrication facility. After the order-lot pegging process assigns lots in the fab to orders and calculates the required quantity of wafers for each product type to meet customers' orders, the decisions on the formation of input release lots should be made to minimize the production costs of the release lots. Since the number of lots being processed in the wafer fab directly is related to the productivity of the wafer fab, the input lot formation is crucial process to reduce the production costs as well as to improve the efficiency of the wafer fab. Here, the input lot formation occurs before every shift begins in the semiconductor wafer fab. When input quantities (of wafers) for product types are given from results of the order-lot pegging process, lots to be released into the wafer fab should be formed satisfying the lot size requirements. Here, the production cost of a homogeneous lot of the same type of product is less than that of a heterogeneous lot that will be split into the number of lots according to their product types after passing the branch point during the wafer fabrication process. Also, more production cost occurs if a lot becomes more heterogeneous. We developed a multi-dimensional dynamic programming algorithm for the input lot formation problem and showed how to apply the algorithm to solve the problem optimally with an example problem instance. It is necessary to reduce the number of states at each stage in the DP algorithm for practical use. Also, we can apply the proposed DP algorithm together with lot release rules such as CONWIP and UNIFORM.

FISSION PRODUCT RELEASE ASSESSMENT FOR END FITTING FAILURE IN CANDU REACTOR LOADED WITH CANFLEX-NU FUEL BUNDLES

  • Oh, Dirk-Joo;Jeong, Chang-Joon;Lee, Kang-Moon;Suk, Ho-Chun
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 추계학술발표회논문집(1)
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    • pp.651-656
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    • 1997
  • Fission product release (FPR) assessment for End Fitting Failure (EFF) in CANDU reactor loaded with CANFLEX-natural uranium (NU) fuel bundles has been peformed. The predicted results are compared with those for the reactor loaded with standard 37-element bundles. The total channel I-131 release at the end of transient for EFF accident is calculated to be 380.8 TBq and 602.9 TBq for the CANFLEX bundle and standard bundle channel cases, respectively. They are 4.9% and 7.9% of the total inventory, respectively. The lower total releases of the CANFLEX bundle O6 channel are attributed to the lower initial fuel temperatures caused by the lower linear element power of the CANFLEX bundle compared with the standard bundle.

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SSMS에서 동적 공구할당을 고려한 부품투입 알고리즘의 시뮬레이션 분석 (Simulation Analysis of Part Release Algorithm under Dynamic Tool Allocation in SSMS)

  • 이충수
    • 한국시뮬레이션학회논문지
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    • 제8권1호
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    • pp.63-76
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    • 1999
  • Recently in manufacturing environment, manufacturing order is characterized by unstable market demand, shorter product life cycle, a variety of product and shorter production lead time. In order to adapt this manufacturing order, flexible manufacturing systems(FMS) in manufacturing technology advances into the direction that machines become further versatile functionally and that tools are controlled by fast tool delivery device. Unlike conventional FMS to mainly focus on part flow, it is important to control tool flow in single-stage multimachine systems(SSMS), consisting of versatile machines and fast tool delivery device. This research is motivated by the thought that exact estimation of tool competition at part release in SSMS enhances the system performance. In this paper, in SSMS under dynamic tool allocation strategy to share tools among machines, we propose real-time part release and tool allocation algorithms which can apply real factory and which can improve system performance.

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일본에서의 제품책임의 현상과 기술사의 대응 (Today's Product Liability's Circumstance of Japan and Correspondence of Consulting Engineer)

  • Naoshi Hondao
    • 한국기술사회:학술대회논문집
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    • 한국기술사회 1994년도 제24회 한일기술사 합동 Symposium (일본편)
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    • pp.138-140
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    • 1994
  • Product liability law is published at 1st July '94 after long study and discussion. Product liability research commitee of Japan Consulting Engineer's Association that was started on september '91, is continuing the research of technical problems and consulting business for product liability. The Ministry of International Trade and Industry release the manual of product liability for an enter prise that is the standard to performe this problems in Japan. These gists of the manual and future business of Japan consulting engineer for these problems are mentioned.

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사출 금형의 밀핀 설계를 위한 경험적 설계 접근법 (A Heuristic Approach for an Layout and Sizing of an Ejector Pin)

  • 이희성;변철웅;이수홍
    • 한국CDE학회논문집
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    • 제9권2호
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    • pp.112-121
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    • 2004
  • As customers demands are rapidly changing, a product life cycle is getting shorter and a product model is forced to be changed frequently. An ejecting design system becomes more important for high productivity to eject a product in high temperature without any damage. For example, an ejector pin that is a key component of the system can cause high local stresses and strains in the molding at the time of ejection. The number, the size, and the location of pins are important to make a smooth ejection. Therefore we propose an analytical approach with the aid of designer’s experience to calculate a total release force and pressure distribution so that the number, the size, and the location of pins can be easily determined. As a part of the result, the design system is built by Intent! with AutoCAD 2000 and a video player deck example is presented to verify the approach.

A Novel Drug Delivery Approach to Olanzapine Orally Dispersible Tablet (ODT) in the Phase of Schizophrenia and Its Pharmacokinetics

  • Kim, Hyun-Jo;Park, Jeong-Hwan
    • Journal of Pharmaceutical Investigation
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    • 제40권5호
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    • pp.297-304
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    • 2010
  • The present work focuses on preparation of olanzapine, orally dispersing tablets by direct compression method. Effect of super disintegrant crospovidone, disintegration time, drug content on in vitro release has been studied. A factorial design was employed in formulating a prompt dispersible tablet. The selected independent variables crospovidone and fmelt showed significant effect on dependent variables i.e. disintegration time and percent drug dissolved. Disintegration time and percent drug dissolved decreased with increase in the level of crospovidone. The similarity factor $f_2$ was found to be 97.48 for the developed formulation indicating the release was similar to that of the marketed formulation. Pharmacokinetics of olanzapine after single-dose oral administration of orally disintegrating tablet in normal volunteers were evaluated and the results showed that PK parameters (Cmax, Tmax, AUC) of the designed ODT matrix were similar to those of commercial product, Zyprexa Zydis$^{(R)}$ as a reference.

의약품 제조설계 및 조작분석의 최적화에 관한 연구 - 정제제조의 최적화 (Mathematical Optimization Techniques in Drug Product Design and Process Analysis. Optimization Techniques in Tablet Design)

  • 김용배
    • 약학회지
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    • 제18권1호
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    • pp.49-58
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    • 1974
  • Tablet product design problem was structured as constrained optimization problem and subsequently solved by multiple regression analysis and Lagrangian method of optimization. Aluminum flufenamate was the drug chosen and microcrystalline cellulose nad starch were the binder and disintegrant, respectivley. The effect of the binder and disintegrant concentration on tablet hardness, friability, volume, in vitro release rate, and urinary excretion rate of drug in human subjects was recorded. Since a reasonably rapid release rate of drug is generally an important objective in the design of solid dosage form, optimization of this parameter was employed in studying the applicability of constrained optimization to a pharmaceutical product design problem. In addition to finding optimal sitivity analysis studies to such problems was also illustratd. It would appear that prediction of the in vivo t$_{50%}$ response from a knowledge of the incitro t$_{50%}$ response can be made fairly accurately for the tablet system used in this study.

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The Optimal Release Time in Cost Model Using PCLS Model

  • Song, Kwang Yoon;Chang, In Hong;Choi, Min Su;Lee, Da Hye
    • 통합자연과학논문집
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    • 제9권3호
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    • pp.206-214
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    • 2016
  • The basic goal of software development is to produce high quality software at low cost. Therefore, when to stop software testing and release the software product is a significant point in the software development. The software cost model is an effective tool used to help software developers control costs and determine the release time. In this paper, we discuss the cost model to apply all 6 models with consideration of time to remove errors, cost of removing each error and risk cost due to software failure. We show the impact of cost coefficients and parameter values on the expected total cost by changing the values and comparing the optimal release times.