• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.947-951
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• 2005

The concept of group technology has been successfully applied to many production systems including flexible manufacturing systems. In this paper we apply group technology principles to the economic lot scheduling problem which has been intensively studied over 40 years. We obtain a production schedule of several family products on a single facility where setup times and costs can be reduced by using the concept of group technology. We develop a heuristic algorithm and a hybrid genetic algorithm for the group technology economic lot scheduling problem (GT-ELSP). Numerical example shows that the developed heuristic and the hybrid genetic algorithm outperform the existing heuristics.

• 한국IT서비스학회:학술대회논문집
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• 2003.05a
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• pp.215-221
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• 2003

In today's rapidly changing business environment, quality of responsiveness to customer requirements for short order cycles and on time delivery is becoming more important and considered as one of critical success factors in supply chain management. Yet despite its importance on reducing transportation cost and improving customer service, little attention has been given to the transportation planning system in Korea SI industry. In this paper, we present development of transportation planning system especially to deal with vehicle routing problem which has the goal to minimize the costs of daily transportation operation and to maximize customer delivery service. The system architecture with other enterprise application is presented and real-world constraints are well incorporated into the system by combining constraints programming and meta heuristics.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.11a
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• pp.191-194
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• 2004

차세대 인터넷 서버는 인터넷을 통하여 여러 사용자에게 HDTV 급 고품질 멀티미디어 서비스를 제공하고자 개발된 시스템이며, 이를 위하여 디스크 연결 및 네트워크 기능을 정합 시킨 특화된 NS 카드를 개발하였다. Contents Container 파일 시스템은 NS 카드 전용으로 개발된 멀티미디어 파일 시스템이며, 본 논문에서는 Contents Container 파일 시스템에 대한 개발 내용을 기술하고, 개발 시스템의 장단점을 파악하고자 EXT3 파일 시스템과 비교 분석하였다.

• Journal of Information Technology Services
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• v.7 no.1
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• pp.63-87
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• 2008

This study investigates the effects of individual and group level factors on the use of GSS (Group Support System) and task performance from GSS use. GSS facilitates the group work, so that GSS adoption is not necessarily influenced only by individual perceptions on information systems as TAM insists. Adaptive Structuration. Theory (AST) joins with TAM in our study to explain the adoption and success from GSS use. AST contends that the success of IS is not necessarily the technical fit between tasks and technology, instead the political outcome among user socializations. We found that collected data from 303 individual IT staffs in a national bank. Our results demonstrate that traditional theories on TAM (Technology Acceptance Model) need to be refined, when considering the TTF(task-technology fit). TTF render high influences on PU(perceived usefulness). PEU(perceived ease of use) and FOA(faithfulness on appropriation). And FOA influences highly on our dependent variable. Implications and directions for future research are discussed.

• Entomological Research
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• v.48 no.5
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• pp.372-383
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• 2018

Leptocimbex formosanus group of Leptocimbex Semenov 1896, Cimbicidae is defined and the relationships and characteristics are provided. Two new species of this group are described from Hunan and Yunnan Provinces in China: Leptocimbex shinoharai Yan & Wei sp. nov. and L. naitoi Yan & Wei sp. nov. Redescriptions of the three known species of L. formosanus group (L. formosanus Enslin 1911, L. dendrobii Rohwer 1915 and L. nigropropodea Wei & Deng 2002) and a key to all known species of this group are provided.

• Natural Product Sciences
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• v.24 no.4
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• pp.284-287
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• 2018

A new isoprenylated acetophenone, acronyculatin P (1) as well as two known compounds, 3',5'-diisoprenyl-2',4'-dihydroxy-6'-methoxyphenylethanone (2) and 3'-isoprenyl-2',4',6'-trihydroxyphenylethanone (3) were isolated from the stem bark of Acronychia pedunculata (L.) Miq. The structures were determined by HRESIMS, 1D and 2D NMR. The inhibitory activity of the isoprenylated acetophenone derivatives against murine leukemia P-388 cells showed compound 1 moderate activity with $IC_{50}$ $15.42{\mu}M$.

• Natural Product Sciences
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• v.28 no.2
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• pp.58-61
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• 2022

Three isoprenylated flavanones were isolated from the leaves of Flemingia lineata (L.) Aiton. Among them are two new flavanones, flemilineatins A and B (1-2), along with 6-isoprenyl eridioctyol (3). Their structures were determined using HRESIMS data and NMR spectra. Flavanones 1 - 3 were assayed in the HeLa cancer cells. Compound 1 showed moderate activity with an IC₅₀ value of 11.2 μM.

• Natural Product Sciences
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• v.28 no.1
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• pp.40-43
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• 2022

Three isoprenylated flavanones were isolated from the leaves of Flemingia lineata (L.) Aiton. Among them are two new flavanones, flemilineatins A and B (1-2), along with 6-isoprenyl eridioctyol (3). Their structures were determined using HRESIMS data and NMR spectra. Flavanones 1-3 were assayed in the HeLa cancer cells. Compound 1 showed moderate activity with an IC₅₀ value of 11.2 μM.

• Elastomers and Composites
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• v.50 no.3
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• pp.189-195
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• 2015

In this study, we prepared epoxidized poly ethylene-ter-1-decene-ter-divinylbenzene (Epo-PEHV) as a reactive compatibilizer to prevent phase separation phenomenon which occurs upon blending polypropylene (PP) and ethylene-vinyl alcohol copolymer (EVOH). Firstly, PEHV was prepared under high catalyst activity according to content of catalyst and cocatalyst. After then, we modified vinyl group of the terpolymer with epoxy group. We observed that the terpolymer was successfully epoxidized by 1H-NMR and FT-IR analysis. The Epo-PEHV was added by 2, 5, 10% in PP/EVOH blends. The morphologies and mechanical properties of PP/Epo-PEHV/EVOH blends were analyzed by SEM and UTM, respectively. Epo-PEHV enhanced the interfacial adhesion of PP and EVOH blends.

• Bulletin of Food Technology
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• v.26 no.2
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• pp.102-108
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• 2013