• 한국관개배수논문집
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• 제5권2호
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• pp.33-40
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• 1998

In this research the valve-opening calculation program for operation of valve was developed to determine the valve-openings corresponding to discharges in pipeline system. Personal Computers can be used for hydraulic calculations of the steady flow condit

• 오토저널
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• 제14권3호
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• pp.80-89
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• 1992

An experimental study of in-cylinder of flow and combustion characteristics in two gasoline engines of different intake ports which are denoted as original port and masked shroud head (MSH) ports is presented. The flows generated by the MSH and the original port are invest- igated by laser Doppler velocimeter(LDV) under steady flow and motoring (non-firing) condit -ions. Combustion characteristics with different swirl levels produced by two intake ports are analyzed by combustion pressure measurement and statistical calculation. The swirl inside the cylinder of the MSH port engine is found to be much higher than the original port, and the MSH has a large eddy motion of cylinder diameter size. Using ensemble average method to valuate engine turbulence under motoring condition, the MSH port engine is shown to have h -igher turbulence intensity than the original port, so that the effect of the MSH port on fast burn is shown. Also the cyclic variations of peak pressure and the reaching time in the MSH port are apparently reduced.

• Journal of Microbiology
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• 제43권3호
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• pp.301-307
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• 2005

The feasibility of laccase production by immobilization of Pleurotus ostreatus 1804 on polyurethane foam (PUF) cubes with respect to media composition was studied in both batch and reactor systems. Enhanced laccase yield was evidenced due to immobilization. A relatively high maximum laccase activity of 312.6 U was observed with immobilized mycelia in shake flasks compared to the maximum laccase activity of free mycelia (272.2 U). It is evident from this study that the culture conditions studied, i.e. biomass level, pH, substrate concentration, yeast extract concentration, $Cu^{2+}$ concentration, and alcohol nature, showed significant influence on the laccase yield. Gel electrophoretic analysis showed the molecular weight of the laccase produced by immobilized P. ostreatus to be 66 kDa. The laccase yield was significantly higher and more rapid in the packed bed reactor than in the shake flask experiments. A maximum laccase yield of 392.9 U was observed within 144 h of the fermentation period with complete glucose depletion.

• 한국수소및신에너지학회논문집
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• 제14권3호
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• pp.247-257
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• 2003

To investigate the effect of preparing condition on the physical properties of carbon nanotubes suitable for optical applications, carbon nanotubes were synthesized by thermal chemical vapor deposition using Ni particles as a catalyst on stainless steel substrate and acetylene as a reactant gas. To examine the physical and optical properties, SEM, TEM, Ram an, UV-visible, and photoluminescence spectroscopy were used. The physical properties of carbon nanotubes such as diameter, degree of growth density and morphology were closely related to such experimental conditions as Ni particle size, growing pressure, and etching condit on of Ni particles, it appeared from the light absorbance and photoluminescence spectra of carbon nanotube mixture prepared with an addition of a photopolymer, P3HT(Poly(3-hexylthIop hene)) that carbon nanotube could do a role as a kind of electron acceptor for solar cell application.

• Archives of Plastic Surgery
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• 제48권4호
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• pp.404-409
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• 2021

Background To date, there are no consensus guidelines for management of lymphatic leak in groin vascular reconstruction patients. The goal of this study is to review the relevant literature to determine alternatives for treatment and to design an evidence-based algorithm to minimize cost and morbidity and maximize efficacy. Methods A systematic review of the literature was conducted per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Two independent reviewers applied agreed-upon inclusion and exclusion criteria to eligible records. Studies that included patients who underwent groin dissection for oncologic diagnoses and level 5 data were excluded. Interventions were then categorized by efficacy using predetermined criteria. Results Our search yielded 333 records, of which eight studies were included. In four studies, the success of lymphatic ligation ranged from 75% to 100%, with average days to resolution ranging from 0 to 9. Conservative management in the form of elevation, compression, and bedrest may prolong time to resolution of lymphatic leak (14-24 days) and therefore cost. Conclusions The majority of patients should be offered early operative intervention in the form of lymphatic ligation with or without a primary muscle flap. If the patient is not an operative candidate, a trial of conservative management should be attempted before other nonsurgical interventions.

• Nuclear Engineering and Technology
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• 제40권1호
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• pp.49-68
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• 2008

The purpose of this paper is to extensively review the condition monitoring (CM) techniques using empirical models in an effort to reduce or eliminate unexpected downtimes in general industry, and to illustrate the feasibility of applying them to the nuclear industry. CM provides on-time warnings of system states to enable the optimal scheduling of maintenance and, ultimately, plant uptime is maximized. Currently, most maintenance processes tend to be either reactive, or part of scheduled, or preventive maintenance. Such maintenance is being increasingly reported as a poor practice for two reasons: first, the component does not necessarily require maintenance, thus the maintenance cost is wasted, and secondly, failure catalysts are introduced into properly working components, which is worse. This paper first summarizes the technical aspects of CM including state estimation and state monitoring. The mathematical background of CM is mature enough even for commercial use in the nuclear industry. Considering the current computational capabilities of CM, its application is not limited by technical difficulties, but by a lack of desire on the part of industry to implement it. For practical applications in the nuclear industry, it may be more important to clarify and quantify the negative impact of unexpected outcomes or failures in CM than it is to investigate its advantages. In other words, while issues regarding accuracy have been targeted to date, the concerns regarding robustness should now be concentrated on. Standardizing the anticipated failures and the possibly harsh operating conditions, and then evaluating the impact of the proposed CM under those conditions may be necessary. In order to make the CM techniques practical for the nuclear industry in the future, it is recommended that a prototype CM system be applied to a secondary system in which most of the components are non-safety grade. Recently, many activities to enhance the safety and efficiency of the secondary system have been encouraged. With the application of CM to nuclear power plants, it is expected to increase profit while addressing safety and economic issues.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2004년도 춘계 종합학술대회 논문집
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• pp.553-561
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• 2004

20세기 이후 우리의 경우는 숨가쁘게 유입되는 세계문화와 기존 우리 문화와의 소화 불량적 만남으로 혼돈의 문화를 이룩하였으며, 반도체 수출이나 IT산업에 있어서, 최강의 기술력 보유국(保有國)이라는 자리를 점유하면서도 공허한 심정을 떨칠 수 없게 되었다. 그러한 한국의 현대사와 동시대적 상황 가운데 작금의 현실을 살아가는 우리들은 정치적, 사회적, 문화적 측면에서 혼돈과 현기증을 복합적으로 체감하게 된다. 대중화(大衆化), 소비화(消費化)된 사회는 경제력 향상을 초래(招來)하였으나 그 출발은 익명(匿名)의 대중출현에 의해 가능했으며, 군중(群衆) 속에서의 고독, 소외(疏外), 익명성(匿名性), 몰개성성(沒個性性), 문화의 상품화(商品化) 등의 삶을 동반하고 있다. 본인의 작품에는 이와 같은 사회 현상(現想)들이 도시적 인간상을 통해 드러난다. 소비문화에 노출된 채 그것이 내뿜는 시각 이미지와 유혹에 포위되어 살아가는 인간은 끊임없는 소유욕(所有慾)에 둘러싸여 자신의 가치를 높이기 위한 모든 것을 공간 안에 가둔다. 이들은 몰개성화된 모습으로, 때로는 동물인지 사람인지 알아볼 수 없는 형상으로 도시의 공간에 존재한다. 이는 산업화된 도시의 파괴되어가는 자연 환경을 고발하기 위한 하나의 상징체(象徵體)로서 인간의 소유욕(所有慾)안에 속해있는 제 3의 존재이며 도심속에 갇혀 사는 우리들의 초상화(肖像畵)인 것이다. 본인은 위와 같은 형상을 통하여 현대 도시문명의 현실 속을 살아가는 인간의 객관적 삶과, 익명성(匿名性)에 묻혀 표현되지 못한 욕구와 감정의 대립을 분석해 봄으로써 우리들이 가져야 할 자생성(自生性)과 정체성(停滯性)을 제시하고자 한다.eferences.촉진, 중요 연구 주제의 도출 및 연구 진행 계획을 수립하고, 국제적 산학 협력 강화를 통해 공동 연구를 도출하는 자리를 마련함. $\textbullet$본 학술회의에서 발표된 논문들을 취합하여, 논문집 및 CD-ROM을 제작하여 세계적 수준의 연구 결과를 알리고 이 분야에 관련된 학문, 기술 발전에 큰 도움이 됨.emove effectively radioactivity with in Adsorbent. As cleaning heavy water adsorbent and drying on each condition (temperature for drying and hours for cleaning). Because there is something to return heavy water adsorbent by removing impurities within adsorbent when it is dried o high temperature. After operating, we have been applying this research to the way to dispose heavy water adsorbent. Through this we could reduce solid waste products and the expense of permanent disposal of radioactive waste products and also we could contribute nuclear power plant run safely. According to the result we could keep the best condit

• 한국광학회지
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• 제11권2호
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• pp.73-79
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• 2000

사출성형법으로 제조된 $fheta$렌즈를 주사렌즈로 상요하는 Laser Scanning Unit의 주주사 및 부주사 방향의 빔경을 측정했다. 주주사 빔경의 경우 $62muextrm{m}$~ $68\mu\textrm{m}$로써 설계치와 유사한 성능을 보이지만 부주사 빔경의 경우 $78\mu\textrm{m}$~$115\mu\textrm{m}$로써 꽤 큰 빔경편차( $37\mu\textrm{m}$)를 나타내었다. 사출성형렌즈에서는 냉각.고화시 수축에 의한 형상오차와 불균일 냉각에 의한 내부왜곡(복굴절)이 발생하게 되는데, 이는 결국 파면수차(빔경확대)를 발생시키게 되고 결국 레이저프린터의 화상열화로 나타나게 된다. 본 논문에서는 부주사 빔경편차의 주요인을 밝혀내기 위해 복굴절(편광비) 및 $f\theta$렌즈의 비구면 형상을 측정하였다. 그리고 측정된 비구면 형상치를 CODE-V(미국 ORA사의 광학설계 프로그램)에 입력하여 부주사 상면만곡을 계산하고, 이와 설계 초점심도를 비교.분석함으로써 복굴절이 부주사 빔경편차의 주요인임을 알 수 있었다.