This paper presents the application of integrated mathematical programming approach for the design of cellular manufacturing. The cores of the proposed approach are two phases; concurrently a dealing with exceptional elements(EEs) and cell formation and facilities layout design. A policy dealing with EEs considers minimizing the total costs of three important costs ; (1) intercellular transfer (2) machine duplication and (3) subcontracting. And important issue is the calculation of the number of machines needed by considering the maximum utilization of machines and the available capacity of a machine that can be transferred for intercell moving is an key. Facilities layout design is considered to reflect the real field data such as the operation sequence of the parts to be manufactured. quadratic. The model is formulated as mixed integer programming that is presented to find the optimal solution.

The purpose of this study is to propose guidelines for introducing the Just-In-Time (JIT) production system to enhance the competitiveness of Korean manufacturing companies. This study employed an extensive survey on the use of the JIT production systems among different korean manufacturing companies to understand the current status of the JIT production system in use and to identify the benefits from implementing JIT production system. The survey has covered 170 manufacturing companies of different sizes from various sectors of Korean industries including electronics, automobiles, machineries, and textiles. In conclusion, our research results support that the JIT production system would contribute to increase the manufacturing performances of Korean manufacturing companies through lower inventory level and increased quality level.

This study was carried on the quality characteristics of cake prepared with Co(com oil) containing MCT(medium chain triglycerides), which is used as a fat substitute. In tile cake prepared with MCT-CO containing 10~30% MCT, the appearance and the degree of gelatinization were similar to those of cake prepared with NS-CO(non-substituted corn ell) Cake batter prepared with MCT-CO showed higher specific gravity and consistency than those of cake prepared with NS-CO and increased by increasing MCT contents. The baking loss of cake prepared with MCT-CO was more than that of cake prepared with NS-CO and increased by increasing MCT contents as well. The rheological properties of cake represented significant different by MCT substitution ratio(p〈0.05). Gumminess, hardness and chewiness of cake prepared with MCT-CO containing 20~30% MCT were about 2 times higher than those of cake prepared with NS-CO, while springiness and cohesiveness showed similar pattern between the cake prepared with MCT-CO or NS-CO. In sensory evaluation, appearance. color and flavor of cake prepared with CO substituted by MCT up to 100% were better assessed and the taste was better in range of 30% MCT-CO but the texture was less accepted than that of cake prepared with NS-CO.

The purpose of the present study is to determine an optimum composition using cheaper powders keeping with high performance of hard rock cutting diamond saw blade. With 50Fe-20(Cu . Sn)-30Co specimen, a part of Co was replaced by Ni(5%, 10%, and 15%, respectively). These specimens were hot pressed and sintered for predetermined time at various temperature. Sintering is performed by two different methods of temperature controlled method and specimen dimension controlled method. In order to determine the property of the sintered diamond saw blade, 3 point bending tester, X-ray diffractometer, and SEM were used. As the Co in the bond alloy was replaced by Ni, the hardness of the specimen increased. Thus the 50Fe-20(CuㆍSn)-15Co-15Ni specimen showed the maximum hardness of 104(HRB). The results of 3 point bending test showed that flexure strength decreased along with increase in Ni content. This is attributed to the formation of intermetallic compound(NiSn) determined by X-ray diffraction. The fracture surface after 3 point bending test showed that diamond was fractured in the specimen containing 0%, 5%, and 10%Ni, and the fracture occurred at the interface between diamond and matrix in the specimen containing 15%Ni. The cutting ability test showed that the abrasive property was not changed in the specimen containing 0%, 5%, and 10%Ni. The optimum composition determined in this study is 50Fe-20(CuㆍSn)-20Co-10Ni.

Calcium phosphate powders were successfully synthesized by using re-cycled eggshell and phosphoric acid. The crystallization behavior and powder morphologies of the synthesized powders were dependent on the starting condition of the eggshell, the mixing ratio and method of the eggshell and phosphoric acid, and calcination temperature. In general, -tricalcium phosphate was stably synthesized at about 90 for 1h at each proper mixing ratio. And, the synthesized powders showed the similar microstructures to the morphology of original eggshell with uniform particle sizes. In this study, the calcium phosphate powders were synthesized with eggshell in various processing method. And their unique microstructures obtained from the eggshell were also. observed. The crystalline developments and microstructures of the synthesized powders were examined by X-ray diffractometer and scanning electron microscopy

Nanoscale Cu-Ni alloy nanopowders have been produced by a pulsed wire evaporation method in an inert gas. The effect of Cu-Ni alloy nanopowders as additives to motor oil on the tribological properties was studied at room temperature. The worn surfaces were characterized by Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDS). Cu-Ni alloy nanopowders as additives lowered coefficient of friction and wear rate. It was found that a copper containing layer on the worn surface was formed, and deposited layers of the metal cladding acted as lubricant on the worn surface, reducing the friction coefficient. It was clearly demonstrated that Cu-Ni alloy nanopowders as additives are able to restore the worn surface and to preserve the friction surfaces from wear

A new concept of tungsten heavy alloy composite was suggested and manufactured in this study for the kinetic energy penetrator. The composite heavy alloy was composed of two parts, the center was molybdenum added heavy alloy compositions which were designed to promote the self-sharpening effect and outside was conventional heavy alloy in order to sustain the severe stress condition in the muzzle during the firing. The center part showed an intergranular and brittle mode at tungsten/tungsten interfaces by which self-sharpening effect could be activated. On the other hand, that of outside showed conventional ductile fracture mode under high strain rate condition. From the sub-scale penetration test, the depth of penetration in heavy alloy composites showed greater values than those of conventional tungsten heavy alloys. It is suggested that the heavy alloy composite could be considered as one of the future penetrator materials.

SPG (Shirasu porous glass) 관형 막이 설치된 회분식 막유화 장치를 사용하여 단분산 칼슘 알지네이트 미립자를 제조하기 위한 막유화 공정변수의 최적조건을 결정하였다. 막유화의 공정변수로는 연속상에 대한 분산상의 비율, 알지네이트 농도, 유화제의 종류와 농도, 안정제 농도, 가교제 농도, 교반속도, 막간 압력차 및 SPG 막의 세공크기로 설정하고, 이들 변수가 제조된 알지네이트 미립자의 입자 크기와 분포에 미치는 영향을 검토하였다. 막유화의 공정변수들 중에서 연속상에 대한 분산상의 비율, 막간 압력차 그리고 알지네이트 농도가 증가할수록 미립자의 크기가 증가하였다. 반면 유화제의 농도, 교반속도 그리고 가교제의 농도가 증가할수록 미립자의 크기가 감소하였다. 세공 크기 2.9mum인 SPG막을 사용한 경우 막유화의 공정변수 조절을 통해 최종적으로 평균 입자 크기 6mum, 크기 분산도 1.1인 단분산 알지네이트 미립자의 제조가 가능하였다.

An emulsion of octadecamidoethylaminoethyl dodecate (which provides softness) and an emulsion silicone oil KF-96 (which provides lubricity) were separately synthesized. Then PP finishing softeners (SSA-7) was prepared by blending of the synthesized emulsions with beef tallow hardened oil (a softness improving agent). PP finishing treatment was carried out with the prepared SSA-7 and PP finishing resin by a one bath method, and several physical properties were tested. As a result, crease recovery, tear strength, softness, lubricity, and bending resistance were all good, indicating that the prepared SSA-7 is a good PP finishing softener.

원자력 발전의 고온 가스로(high temperature gas-cooled reactor, HTGR)의 냉각제로 사용되는 He가스의 열에너지를 이용하여 물을 분해해서 수소를 생산하는 "열화학적 수소제조 IS프로세스"에 대해 설명하였다. 특히, 분리막 기술의 이용에 관한 연구를 중점으로 정리하였다. 고온 원자력 열에너지를 이용한 열화학적 수소 제조법은 실현 가능한 단계까지 왔다고 생각되며, 아직 연구 개발 과제가 많이 남아 있지만, 미래의 청정에너지 중의 하나인 수소를 대량 생산할 수 있는 가능성을 갖고 있다.

Product liability is the law of the manufacturer's responsibilities for the consumers' personal injuries or the losses of property resulted from defective products. In today's many countries, the product liability law are being enacted because of the safety of product use and the protection of consumer's right. In korea, the product liability is going to enforce on July 1, 2002. Though the construction of product liability response system is urgent situation, domestic manufacture company's PL response system is not nearly prepared in present. Consequently, the purpose of this study is to discuss the Quality Management's importance and the PL countermeasures by presenting the difference of PL response system construction degree by the Quality Management Maturity degree