• 한국경영과학회:학술대회논문집
• /
• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
• /
• pp.1-7
• /
• 2003

This paper considers an Integrated one-vendor multi-buyer production-inventory model where the vendor manufactures multiple products In lot at Her associated finite production rates In the model. It is allowed for earth product to be shipped In lot to the buyers before the whole product production is not completed yet. Each product lot is dispatched to the associated buyer In a number or shipments. The buyers consume their products at fixed rates. The objective is to the production and shipment schedules in the Integrated system. which minimizes the mean total annual cost per unit time. The mean total annual cost consists or production setup cost inventory holding cost and shipment cost. For the model, an Iterative optimal solution procedure with shipment consolidation policy incorporated is derived. It is then tested through numerical experiments to show how efficient and effective He shipment consolidation policy is.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 춘계학술대회 논문집
• /
• pp.811-814
• /
• 1997

The injection molding process has been developed as a very important technology for the automotive and electric industries in recent years. But, in the injection molding products with rib-web structures, partial deformation by thermal volumetric shrinkage called Sink Mark, is occurred. In this study, to make explicitly characteristics of sink mechanism, an experimental approach was taken by using multi T-shaped mold cavity and FEM simulation. As a result, pressure on the packing process and the rib thickness are the most effective on sink mark depth. On the other hand, melt temperature has no effect on sink mark depth fot the same rib thickness.

• 제어로봇시스템학회논문지
• /
• 제9권9호
• /
• pp.727-735
• /
• 2003

The determination of completion time constitutes an important step in developing algorithms for short-term production scheduling. Existing completion time algorithms of multi-product batch processes often assume that intermediate storage tanks are always available when it is needed. In this paper, we consider a serial multi-product batch plants with ZW and NIS policy intermediate storge tank. We limit storage residence time and allocated products in the intermediate storage tank to minimize the quality change of the stored material as well as to reduce the clearing time during product change. A set of recurrence relations is suggested to calculate the completion times for the given batch sequence of products on all processing units. Also analytic solution for the suggested model is solved by a graphical method. The effectiveness of these results is proved by a few illustrative examples.

• 산업경영시스템학회지
• /
• 제26권1호
• /
• pp.85-94
• /
• 2003

In this paper, a mathematical model is developed for economic design of multi-stage distribution system that consists of factory, central distribution centers, local distribution centers and retailers. The retailers are supplied products from different stage suppliers according to order size. The retailers are supplied products from factory if demand amount is large, central distribution center if medium, local distribution center if small. The economic design is to determine the economic size of facility factors that consist of distribution system. The cost factors are transportation cost from supply places to demand places, handling cost at distribution centers and inventory holding cost at retailers. It is to determine the transportation route of each retailer, the size and number of the vehicle at factory and distribution centers, the handling amount at distribution centers in order to minimize the total costs. The mathematical model is represented, the solution procedure is developed, and a numerical example is shown.

• Nuclear Engineering and Technology
• /
• 제46권6호
• /
• pp.825-836
• /
• 2014

Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model [1,2], and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data [3], which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

• Nuclear Engineering and Technology
• /
• 제52권12호
• /
• pp.2867-2873
• /
• 2020

In reprocessed uranium, derived from an impoverished fuel of light-water moderated reactors, there are isotopes of ^{232, 234, 236}U, which make its recycling remarkably difficult. A method of concentration of ²³⁵U target isotope in cascade's additional product was proposed to recover the isotopic composition of reprocessed uranium. A general calculation procedure is presented and a parameters' optimization of multi-flow cascades with additional products. For the first time a numeric model of a cascade that uses the cuts of partial flows of stages with relatively high separation factors was applied in this procedure. A novel computing experiment is carried out on separation of reprocessed uranium hexafluoride with providing a high concentration of ²³⁵U in cascade's additional product with subsequent dilution. The parameters of cascades' stages are determined so as to allow reducing the ^{232, 234, 236}U isotope content up to the acceptable. It was demonstrated that the dilution of selected products by the natural waste makes it possible to receive a low enriched uranium hexafluoride that meets the ASTM C996-15 specification for commercial grade.

• Advances in concrete construction
• /
• 제5권3호
• /
• pp.289-301
• /
• 2017

The synergistic interactions of supplementary cementitious materials (SCMs) with ordinary portland cement (OPC) in multi-blended systems could enhance the mechanical and durability properties of concrete and increase the amount of cement that can be replaced. In this study, the characteristics of the hydration products as well as paste microstructure of blended cement containing 20% coal fly ash, 10% rice hull ash and 10% sugar mill lime sludge in quaternary blended system was investigated. Portlandite content, hydration products, compressive strength, pore size distribution and microstructural architecture of hydrated blended cement pastes were examined. The quaternary blended cement paste showed lower compressive strength, reduced amount of Portlandite phases, and higher porosity compared to plain hardened cement paste. The interaction of SCMs with OPC influenced the hydration products, resulting to the formation of ettringite and monocarboaluminate phases. The blended cement paste also showed extensive calcium silicate hydrates and calcium aluminate silicate hydrates but unrefined compared to plain cement paste. In overall, the expected synergistic reaction was significantly hindered due to the low quality of supplementary cementitious materials used. Hence, pre-treatments of SCMs must be considered to enhance their reactivity as good quality SCMs can become limited in the future.

• 유통과학연구
• /
• 제15권1호
• /
• pp.51-56
• /
• 2017

Purpose - The study verified the effects of consumers' knowledge perception upon word-of-mouth intention and purchase intention of consumers who were exposed to a lot of information, and examined consumer's behavior from multi-dimensional points of view. Research design, data, and methodology - The study conducted the test of difference between consumer's cognition on importance and satisfaction of HMR product by gap of HMR (Home Meal Replacement) product for IPA analysis. The consumer's reliability and words-of-mouth were measured by the questionnaire method with 4 questions according to Likert 7-point scale. Conversion into z-score removed the difference of variables. Results - The causal relation model for importance, satisfaction and gap, not relying upon multi-dimensional scaling and others, could construct causal relation model to give implications. Difference (d) of the products could lessen consumer's reliability to increase consumer's knowledge perception, word-of-mouth intention, knowledge perception, and purchase intention. Therefore, enterprises should make an effort to lessen consumers' complaint for the products and to elevate consumers' reliability. Enterprises also try to give consumers exact information and to promote purchase intention. Conclusions - Difference (d) of consumers' complaint and/or disappointment decreased consumers' reliability to increase knowledge perception. Enterprises should supply consumers with products according to their requirements to minimize the gap and to give them proper information.

• 한국염색가공학회지
• /
• 제30권1호
• /
• pp.38-50
• /
• 2018

This investigation reported the recent development of 3 dimensional fabrics such as spacer fabric, 3 dimensional multi-layered fabric and 3 dimensional braided fabric. First, we categorized 3 dimensional fabrics into 3 main products; 3 dimensional woven fabrics, 3 dimensional knitted fabrics and 3 dimensional braided fabrics with reviewing the possible main applications. We also reported the research and development trends of 3 dimensional fabrics by analyzing technical trends in industry and research institutes at domestic and overseas. United State, Germany and Japan lead the manufacturing technology for the mainly preform related products to apply in aerospace, automotive, protections, architecture and clothing applications. Lastly, we reviewed the main products of the leading company which manufactured using the 3 dimensional fabrics.

• 소성∙가공
• /
• 제24권5호
• /
• pp.340-347
• /
• 2015

Multi-pass shape drawing is used to manufacture long products of arbitrary cross-sectional shapes. This process allows smooth surface finishes and closely controlled dimensions of the cross-sectional shape. Tube shape drawing for hollow type products provides material savings and weight reduction. The intermediate die shapes are very important in multi-pass tube shape drawing. In the current paper, the design method for the intermediate dies in a tube shape drawing process is developed using a die offset for corner filling (DOCF) method. Underfill defects are related to the radial velocity distribution of each divided section in the deformation zone. The developed intermediate die shape design was applied to the two-pass tube shape drawing with fixed mandrel for manufacturing a hollow linear motion (LM) guide rail. The proposed design method led to uniform and steady metal flow at each divided section. FE-simulations and experiments were conducted to validate the effectiveness of the proposed method in multi-pass tube shape drawing process.