• 제목/요약/키워드: durable

검색결과 936건 처리시간 0.03초

생산 중단되는 내구재의 재고정리를 위한 가격정책 (Dynamic Clearance Pricing Policy for Durable Goods)

  • 이경근;김영석
    • 대한산업공학회지
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    • 제26권1호
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    • pp.66-72
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    • 2000
  • Inventory management of a product not to be produced any more has a great impact on the financial status of a company. Clearance pricing can make bigger sales volume together with great savings of inventory holding cost specially for a durable goods with relatively large inventory carrying cost and accordingly cash inflow can be improved. This paper deals with the inventory management by non-linear clearance pricing with the sales rate which depends on the accumulated sales volume and selling price.

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매설 환경에 따른 파형강 구조물의 부식 특성 연구 (A Study on the Corrosion of Corrugated Steel Structures in Buried Environment)

  • 박연수;김병하;한상호;박선준;서병철
    • 한국구조물진단유지관리공학회 논문집
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    • 제7권1호
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    • pp.147-156
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    • 2003
  • In this research, multiple corrosion factors of buried environments were measured in order to establish a formula for the corrosion character of corrugated steel structures in domestic environments. By substituting corrosion factors for each predicting formula, the durable lifetime was measured, and the measured lifetime was compared with the estimated lifetime by applying existing thickness-measuring techniques. A new usage standard was proposed with these results, in order to create the conclusion below. There are known differences in the soil factors used as variables in estimating the duration caused by the seasonal effects of rainfall and temperature. Comparing the durable lifetime estimated by each predicting formula, the findings show that the California technique is conservative. This study demonstrates that the error range of the AISI technique, which is mostly used as a duration technique, is a very narrow predicting technique as compared with many other countries. Considering that there is on average, a 13% error margin in this study, a proposed safety factor of 0.87 could be used to more accurately predict the duration. The laying time in the California technique is not longer than the whole durability, and as a result, this error margin exists. It is concluded that this study on the open area has been overdue. Based on these findings, it's proposed that this error margin should be applied to the domestic environment through periodic observation, in order to establish the predicting techniques of durable lifetime.

고내구성 재료를 사용한 해양 콘크리트 부재의 휨 거동 특성 (Characteristics of Flexural Behaviors for Marine Concrete Members Using High-Durable Materials)

  • 양은익;김명유;박해균;이동근
    • 한국구조물진단유지관리공학회 논문집
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    • 제12권6호
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    • pp.249-256
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    • 2008
  • 해양콘크리트 구조물의 내구성은 염분의 침투와 확산에 의해 심하게 저하한다. 이로 인해 많은 연구자들이 해양구조물에 대한 내구성을 향상시키기 위한 연구를 수행하여 왔다. 이 연구에서는 광물질 혼화재, 코팅철근, 부식억제제를 사용한 휨 부재에 대하여 4점 휨 시험을 수행함으로써 휨 거동을 비교 평가하고 해양구조물로의 적용성을 검토하였다. 결과에 따르면, 광물질 혼화재와 부식억제제는 초기균열 안전성과 휨 저항에 효율적인 것으로 나타났다. 내구성 재료를 사용하여도 동일 휨 모멘트 구간에서의 인장철근 응력 변화는 적고 부재도 안정된 거동을 보인다. 또한, 내구성 재료를 사용한 부재의 균열간격도 크지 않게 나타났다.

아크릴 공중합체와 지방산 카르바미드의 블렌딩에 의한 내구유연발수제의 제조에 관한 연구;IV. P/C 혼방직물에의 발수가공 (A Study on the Preparation of Durable Softening Water-repellent by Blending Acrylic Copolymer and Fatty Carbamide;IV. Water-repellent Finish of P/C Blended Fabrics)

  • 고재용;홍의석;박홍수
    • 한국응용과학기술학회지
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    • 제13권2호
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    • pp.39-46
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    • 1996
  • Durable softening water-repellenting agent such as PODCW, PDDCW and PEDCW were prepared by blending cationized compound such as poly(octadecyl methacrylate-co-2-diethylaminoethyl methacrylate)[PODC], poly(2-dodecyl methacrylate-co-2-diethyl-aminoethyl methacrylate)[PDDC] and poly(2-ethylhexyl methacrylate-co-2-diethyl-aminoethyl methacrylate)[PEDC], and cationized compound of fatty carbamide, of which synthetic methods were reported in the previous paper, waxes, and emulsifiers. The results of physical tests of the P/C blended fabrics treated with PODCW, PDDCW and PEDCW with and without textile finishing resin, showed a remarkable improvement of the physical properties. The prepared water-repellenting agents, PODCW-6 and PDDCW-1, were treated on P/C blended fabrics with and without resin. For any cases, there are a little changes between initial water repellency and repellency after 3 times washing of the fabrics. Therefore, the water-repellenting agents proved to be a durable agents, and initial water $100^{+}$ and $90^{+}$ point, respectively.

고내구성 재료를 사용한 휨부재의 균열에 따른 염화물 침투 특성 (Characteristics of Chloride Penetration in Cracked Flexural Member using Durable Materials)

  • 진상호;김일순;김명유;양은익;이성태
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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    • pp.401-404
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    • 2008
  • 균열은 콘크리트에 염소이온과 같은 유해한 물질의 침투경로가 되어 내구성에 심각한 열화를 야기한다. 따라서 고내구성 재료를 사용한 콘크리트 휨부재에서의 균열 발생에 따른 염소이온 침투특성을 검토하고자 하였다. 이를 위해, 고내구성 재료를 적용한 보에 하중을 가하여 휨균열을 도입시키고, 촉진 염화물 침투실험(RCPT)과 장기 염화물 침투실험을 실시하여 염화물 침투 특성을 파악하였다. 실험결과에 따르면, 고내구성 재료를 적용한 부재는 균열이 발생하여도 일반 콘크리트 부재에 비해 높은 염화물 침투 저항성을 보였다. 특히 고로슬래그 미분말을 적용한 경우, 균열 부재의 장기 염화물 침투 실험에서 탁월한 염화물 침투 저항성을 보였다.

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알루미늄 중력주조용 내구성 도형제의 도형조건에 따른 내마모 및 내열특성 연구 (A Study on the Wear and Heat Resistance Properties of Durable Moldwash Conditions for Al Gravity Die Casting According to Mold Washing Process Condition)

  • 김억수;남궁정;박진하;이광학
    • 한국주조공학회지
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    • 제28권5호
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    • pp.237-241
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    • 2008
  • This study has been carried out to investigate the wear and heat resistant properties of durable moldwash agent for Al gravity casting according to mold washing process conditions. The wear properties of coated specimen were performed by sliding wear testing machine and heat resistance were evaluated by measuring the loss of coated moldwash agent during emerging of coated specimen in Al melts. During testing, experimental variables were mold surface temperature, moldwash agent/distilled wear, and additive concentrations. The lower additive concentration and mold temperature caused the smooth surface roughness of coated specimen, It was found that the specimen coated with moldwash/water ratio 1:3, additive concentration 9wt% and mold temperature higher than $200^{\circ}C$ showed superior wear and heat treatment. Also, these results were supported by fluidity test.

지방산 카르바미드/왁스/아크릴 공중합체의 블렌드에 의한 내구유연발수제의 제조에 관한 연구 (IV);P/C 혼방직물에의 발수처리 (A Study on the Preparation of Durable Softening Water Repellents by Blends of Fatty Carbamide/Wax/Acrylic Copolymer(IV);Water Repelling Treatment of P/C Blended Fabrics)

  • 박홍수;배장순
    • 한국응용과학기술학회지
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    • 제12권2호
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    • pp.51-58
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    • 1995
  • To prepare a durable softening water repellent, quaternized octadecyl methacrylate-2-diethyl-aminoethyl methacrylate as a mother resin and quaternized 1, 3-dioctadecyl-2, 7-dioxy-6, 8-di(2-hydroxyethyl)-1, 3, 6, 8-tetraazacyclodecane which increase the softening effect and the hydrostatic pressure blended with waxes and their emulsifier in various proportions to give water repellent PADWC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyestercotton(P/C) blended fabrics treated with PADWC only or addition of textile finishing resin, the physical properties were increased. There was no significant lowering effect in water repellency when PADWC was treated the antistatic agent by the one-bath method, and the effect of water repellency by the adding the catalyst was studied. PADWC was confirmed as durable water repellent with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

The First Pediatric Heart Transplantation Bridged by a Durable Left Ventricular Assist Device in Korea

  • Shin, Jung Hoon;Park, Han Ki;Jung, Se Yong;Kim, Ah Young;Jung, Jo Won;Shin, Yu Rim
    • Journal of Chest Surgery
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    • 제53권2호
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    • pp.79-81
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    • 2020
  • Treatment options for children with end-stage heart failure are limited. We report the first case of a successful pediatric heart transplantation bridged with a durable left ventricular assist device in Korea. A 10-month-old female infant with dilated cardiomyopathy and left ventricular non-compaction was listed for heart transplantation. During the waiting period, the patient's status deteriorated. Therefore, we decided to provide support with a durable left ventricular assist device as a bridge to transplantation. The patient was successfully bridged to heart transplantation with effective support and without any major adverse events.

이동 애드혹 네트워크를 위한 경로 지속성을 고려한 거리벡터 멀티케스트 프로토콜 (Durable Distance Vector Multicasting Protocol for Mobile Ad hoc Networks Based on Path-Durability)

  • 이세영;장형수
    • 한국정보과학회논문지:정보통신
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    • 제33권6호
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    • pp.461-472
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    • 2006
  • 본 논문에서는 distance vector 라우팅 알고리즘에 경로 지속성에 대한 분석을 적용한 Durable Distance Vector Multicast(DDVM) 알고리즘을 제안한다. DDVM은 기존의 distance vector 알고리즘에 PATHS의 분석 내용을 기반으로 한 경로 지속성 정보를 포함하여 견고한 멀티캐스팅 경로를 구성한다. 또한 경로 정보에 목적지까지의 세부적인 경로의 지속성 정보 역시 포함하여 멀티캐스팅 경로 형성의 실패율을 줄이고 보다 지속성 있는 경로를 멀티캐스팅 경로에 포함시킨다. 이러한 경로들을 통해 멀티캐스팅을 수행함으로서 high mobility 환경에서 기존의 알고리즘보다 높은 전송률을 보이며, 실험 결과를 통해 이를 확인할 수 있다.