• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.38-49
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• 2009

In public project market, design-build projects have been increased because of market trend change which enables technical competition. In this condition, its importance is also getting important. Generally, life cycle of design-build project consists of planning, preliminary design, procurement, contract, detail design, start of construction, construction, end of construction, and evaluation. From contractor's viewpoint, it has problems such as difficulties in project management and information sharing because of frequent change of charged division. To solve these problems, it is desirable to change from function-based management system to process-based management system. The purpose of this study is to develop management process model for design-build project by progress phases. This study analyzed main conflicts and decision making factors of each stage in design-build projects, then systemized management subjects' responsibilities and management points' change. And also this study defined the key information that is the key point by project characteristics and progress phases. Based on this analysis, this study did business process modeling from planning stage to construction design check stage. At last, we proposed the way to manage business process by design-build project progress.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.653-658
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• 2016

In this work, we developed a synthetic method for preparing one-dimensional $MnO_2$ nanowires through a hydrothermal method using a mixture of $KMnO_4$ and $MnSO_4$ precursors. As-prepared $MnO_2$ nanowires had a high surface area and porous structure, which are beneficial to the fast electron and ion transfer during electrochemical reaction. The microstructure and chemical structure of $MnO_2$ nanowires were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Brunauer-Emmett-Teller measurements. The electrochemical properties of $MnO_2$ nanowire electrodes were also investigated using cyclic voltammetry and galvanostatic charge-discharge with a three-electrode system. $MnO_2$ nanowire electrodes showed a high specific capacitance of 129 F/g, a high rate capability of 61% retention, and an excellent cycle life of 100% during 1000 cycles.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.553-557
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• 2014

Sulfonated polypropylene (S-PP) is prepared by sulfuric acid-acetone aldol condensation reaction of polypropylene (PP) separator to yield hydrophilic separator surface with a moderate amount of $-SO_3H$ groups. Activated carbon supercapacitor is also fabricated adopting the S-PP separator coated with potassium polyacrylate (PAAK) hydrogel polymer electrolyte. As a result, the hydrophilic surface of S-PP separator involves better physical and electrochemical properties such as decrease in contact angle, improvements of wettability, electrolyte uptake, and ionic conductivity to give higher specific capacitance and long cycle-life.

• Korean Journal of Medicinal Crop Science
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• v.6 no.1
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• pp.44-50
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• 1998

The experiment was carried out to investigate weed occurrence in peony field. The number of weeds was Compositate 9 species, Gramineae 4 species, Craciferae 3 species, Eugarviaceae, Polygonaceae and Scrophularilaceae 2 species, respectively. Weeds classified by life cycle were annual weed 19 species (57.6%), biennial weed 8 species (24.2%), and perennial weed 6 species (18.2%). Weed species and dominance rate by morphological characteristics were grass weed 4 species (12.1%), broad leaf weed 25 species (84.8%), and sedge weed 1 species (3.1 %) . Major dominant weeds were Capsella bursa-pastoris, Chemopodium album var. centrorubrum and Equisetum arvense in late April, and Digitaria sanguinalis, Erigeron canadensis and Echinochlor crus-galli in late June, and Digitaria sanguinalis, Erigeron canadensis and Echinochlor crus-galli in middle August.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.5
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• pp.402-415
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• 2001

Advantages of flash memories are their shock resistance and fast read speed, which is much faster than that of a HDD. Because of these characteristics, they are increasingly used in the traditional household electric appliance and portable handset and therefore, development of file systems which use them as storage medium is increasingly needed. But they have two problems as storage medium. First, data stored in them cannot be overwritten: it must be erased before new data can be stored. Unfortunately, this erase operation usually takes about one second. Consequently, updating data in flash memories takes long time. In this paper, their problem is solved by using a data update mechanism like LFS(Log-structured File System). Second, their erase operations are restricted. We propose novel cleaning policy in order to increase the life cycle. We implemented FAT file system, which is suitable to small storage medium and solved problems, which usually happen in implementing FAT. We evaluated the performance of sequential writes and random writes on our implemented flash file system.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.368-374
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• 1999

This study was designed to investigate effects of pulsed electric field (PEF) treatment on physiological changes of microbial cells, using domestically fabricated pilot scale PEF device. The effect of non-thermal PEF treatment on physiological characteristics of microorganisms was determined by salt resistance, the amount of UV absorbents, cell staining, recovery rate of defected cells, and changes in structure of cell membrane. Salt resistance of Escherichia coli, Bacillus subtilis and Rhodotorula minuta was examined after PEF treatment at 40 kV/cm, 84 pulse, $10{\mu}s$ pulse duration. Approximately $1\;log_{10}$ cell number of viable microorganisms was decreased by addition of salt. PEF treatment significantly increased the amount of UV absorbents at 260 and 280 nm because of leakage from damaged cell membrane by PEF treatment. Although three kinds of microorganisms treated by PEF were difficult to be observed due to their cell membrane damage, untreated cells were clearly observed by a microscope. PEF-treated R. minuta was not stained by methylene blue due to cell membrane defect. When E. coli, B. subtilis and R. minuta were cultured after PEF treatment, they showed 5, 4, and 8 hr longer lag phase, respectively, compared to control, but growth rates were not affected.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1279-1285
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• 2011

Korea is currently underway research to estimate carbon footprint in agriculture centered on the RDA (Rural Development Administration). This study was estimated carbon footprint for major 47 crops. In addition, contribution of inorganic chemical fertilizers, main elements for production of crops were analyzed. The carbon footprint of $5.78E+00kg\;CO_2\;eq.\;kg^{-1}$ for citrus fruit in greenhouse was highest, grape in greenhouse, sweet pepper in greenhouse, ginseng, green pepper in greenhouse were followed by $4.61E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.34E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.23E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.04E+00kg\;CO_2\;eq.\;kg^{-1}$ respectively. Next, production phase contribution of inorganic chemical fertilizer to carbon footprint of crop 1 kg were analyzed mean value 1.88%, 9.06% for single fertilizers and complex fertilizers respectively. And use phase accounted for mean value 14.24%. Therefore, to reduce the fertilization of inorganic chemical fertilizer will be reduced $CO_2$ from crop production, also greenhouse gas emissions of agricultural sector will be reduced.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.42-48
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• 2021

Zn and Al added LiNi0.85Co0.15O2 cathode materials were synthesized to improve electrochemical properties and thermal stability using a solid-state route. Crystal structure, particle size and surface shape of the synthesized cathode materials was measured using XRD (X-ray diffraction) and SEM (scanning electron microscopy). CV (cyclic voltammetry), first charge-discharge profiles, rate capability, and cycle life were measured using battery cycler (Maccor, series 4000). Strong binding energy of Al-O bond enhanced structure stability of cathode material. Electrochemical properties were improved by preventing cation mixing between Li+ and Ni2+. Large ion radius of Zn+ increased lattice parameter of NC cathode material, which meant unit-cell volume was expanded. NCZA25 showed 80% of capacity retention at 0.5 C-rate during 100 cycles, which was 12% higher than that of NC cathode. The discharge capacity of NCZA25 showed 104 mAh/g at 5 C-rate. NCZA25 achieved 36 mAh/g more capacity than that of NC cathod. NCZA25 cathode material showed excellent rate capability and cycling performance.

• Journal of Digestive Cancer Research
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• v.5 no.2
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• pp.113-119
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• 2017

Background: Second line chemotherapy is often considered in advanced gastric cancers. We assessed irinotecan in combination with fluorouracil in patients experienced diseases progression after first line chemotherapy. Methods: Prospective trial was done at 7 centers in republic of Korea. Patients aged 18 years or older with advanced gastric adenocarcinoma and disease progression on or within 4 months after first-line chemotherapy were assigned to receive irinotecan 180 mg/m² and 5-fluorouraicl 400 mg/m² intravenously bolus injection on days 1 and leucovorin 200 mg/m² for 2 hours and 5-fluorouracil 600 mg/m² for 22 hours intravenously infusion on day 2 of a 14-day cycle (FOLFIRI group). The primary endpoint was objective tumor response (OR). Efficacy analysis was by per-protocol, and safety analysis included all patients who received at least one treatment with study drug. Results: Between January 1, 2014 and December 31, 2016, 28 patients were assigned to FOLFIRI treatment. Of those 20 patients were completed the study protocol. Per-protocol analysis, two patients among 20 subjects (10.0%) showed partial response. Overall survivals of FOLFIRI group; median 10.1 months [95% CI 4.9-15.3] Grade 3 and higher adverse event that occurred about 5%, but grade 3 or higher febrile neutropenia or life threatening complication was not reported. Conclusion: Combination chemotherapy with irinotecan, 5-FU, and LV is feasible in gastric cancer patients previously treated with platinum-based chemotherapy

• Proceedings of the CALSEC Conference
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• 1998.10b
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• pp.585-594
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• 1998

이미 전자상거래(EC)가 시간적ㆍ공간적 제약을 극복하고 국경을 초월한 새로운 교역시장 (Cyber Market)으로 등장하고 있으며 세계 자동차 산업은 표준부품의 공동개발 및 조달을 통해 중복투자 방지, 신차개발기간 단축 등 전략적 제휴를 통한 공조ㆍ공생체계 구축을 경쟁적으로 추진하고 있으나 국내 자동차업계는 제품개발, 부품조달, 판매 및 A/S 등 모든 부문을 독자적으로 해결함으로써 경쟁력 제고에 역행하는 경향이 있다. 또한 자동차 선진국과는 달리 국제 경쟁력 강화를 위한 CALS/EC 정보 기반 기술의 실질적인 활용이 미흡한 실정이다. 이러한 현실을 개선하기 위해 최근에 자동차공업협회(KAMA)와 현대, 대우, 기아 자동차 3사는 자동차 산업 CALS 추진 모델(Autopia)의 구축을 추진하고 있다. 추진 내용은 자동차 산업의 전체 Life-Cycle인 제품기획 단계부터 설계, 생산, 구매/조달, 고객지원 단계등 전 분야를 3개 부문(신차개발 프로세스, 구매조달 프로세스, 고객지원 서비스)으로 구분되어 있다. 신차개발 프로세스 부문은 차세대 PDM을 통하여 제품개발 사이클 단축을 추구하며 STEP을 통한 범용적 설계정보 교환 체계 구현이 기반이 된다. 또한 업무 흐름의 불투명성으로 인한 업무의 불균형 현상 타파와 설계 변경의 효율적 대응을 위하여 Workflow Management가 동시공학에 바탕을 두고 도입 적용되어야 한다. CAD 데이터를 비롯한 방대한 데이터의 효율적 관리를 위해서는 각 프로세스별로 독립된 정보를 체계적으로 관리할 수 있는 통합 환경(Integrated Data Environment)을 구성하여 각 프로세스에 걸쳐 데이터의 처리효율을 증대하여야 한다. 신차개발 부문의 핵심 기술이면서도 현업 적용이 초기 단계인 Digital Mockup과 Virtual Reality의 적용을 위해서는 3D 모델링이 기본 설계 방법으로 적용되어야 하며 이를 통한 어셈블리 및 부품구조의 관리가 이루어져야 한다. 구매조달 프로세스 부문은 자동차 업계의 공통 EDI/EC 네트워크 구축을 통한 경제적인 인프라 구조와 함께 부품 조달 체계의 간소화를 추구함으로써 자동차 산업의 대외 경쟁력 강화가 이루어 질 수 있다. 공개구매 시스템의 구축을 통하여 완성차별로 전속 계열화된 수직적인 부품조달 체계와 업체간 정보공유의 폐쇄성을 제거할 수 있고 완전 경쟁에 의한 우량 협력업체 발굴 기회의 확대가 용이하다. 이를 통하여 궁극적으로는 Global Vendor망의 구축이 실현될 것이다. 종합물류 시스템이 구현되면 판매는 경쟁체제, 물류는 공동화가 됨으로써 국가적으로 물류 비용의 절감이 엄청날 것으로 예상된다. 전국에 산재되어 있는 1,000여개의 대리점과 7,000여개의 정비업소를 대상으로 한 정비부품 EDI/EC 시스템이 구축되면 고객 서비스의 효율 향상과 함께 정비업소의 물류 및 재고 비용의 감소, 조달 속도의 향상, 조달 업무의 간소화 등의 효과를 보게 될 것이다. 고객지원 서비스는 정비정보 시스템, 산업정보 시스템, 쇼핑몰 시스템, 등록대행 시스템등을 통하여 일반 국민들이 피부로 느낄 수 있는 시스템으로 구축 되어야 할 것이다.