• 제목/요약/키워드: Chun Doo-Hwan

검색결과 42건 처리시간 0.027초

사 염색의 Spindle 유동에 관한 기초적 연구 (A Fundamental Study on the Spindle Flow of the Yarn Dyeing)

  • 강민성;이호준;노석홍;전두환;김희동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.3156-3161
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    • 2007
  • In the field of yarn dyeing, the most generally employed method is a type of package dyeing which uses a package of cheeses stacked on a spindle made of a perforated tube. In order to understand the process of level dyeing, it is essential to perform a study of the porous flow through the spindle for the cheese dyeing method. In this paper, the axisymmetric, incompressible, Navier-Stokes equations are solved for several spindle configurations using a fully implicit finite volume scheme. For investigating the flow patterns through the spindle, porous diameter and porosity is varied in the present study. The computational results show that the total pressure loss depends only on the velocity of inflow regardless of porous diameter and porosity and a large percentage of the mass flow rate through the spindle is discharged at the upside of the spindle. Therefore, it is required to design a new spindle to obtain the level dyeing.

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In Vitro Sugar Accumulation in Juice Sacs of 'Shiranuhi' Mandarin

  • Moon, Doo-Gyung;Han, Sung-Gap;Joa, Jae-Ho;Kim, Chun-Hwan;Seong, Ki-Cheol
    • 원예과학기술지
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    • 제31권3호
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    • pp.269-274
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    • 2013
  • To further our understanding of sugar accumulation in 'Shiranuhi' mandarin [(C. unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulate], we investigated the patterns of sugar uptake in juice sacs exposed to different concentrations of sucrose, fructose and glucose in vitro. Data was also collected on the change in weight and shape of the in vitro juice sacs over time. Soluble solids content, sugar content and acidity content were highest at 20% sucrose, fructose and glucose solution content; while fructose content was highest at 5% sucrose concentration. Furthermore, the juice sac's fresh weight was highest at 5% sucrose and lowest at 20% fructose content. The shape of the juice sacs also differed in different sugar concentration and type. Overall, sucrose, fructose and glucose content in juice sacs increased with the sugar concentration. These results suggest that sugar translocation into juice sacs is actively induced by high sugar concentration in the medium. Thus, it can be concluded that sugar and acid accumulation in juice sacs increased with sugar concentration in vitro culture.

Experimental Performance Comparison of Dynamic Data Race Detection Techniques

  • Yu, Misun;Park, Seung-Min;Chun, Ingeol;Bae, Doo-Hwan
    • ETRI Journal
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    • 제39권1호
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    • pp.124-134
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    • 2017
  • Data races are one of the most difficult types of bugs in concurrent multithreaded systems. It requires significant time and cost to accurately detect bugs in complex large-scale programs. Although many race detection techniques have been proposed by various researchers, none of them are effective in all aspects. In this paper, we compare the performance of five recent dynamic race detection techniques: FastTrack, Acculock, Multilock-HB, SimpleLock+, and causally precedes (CP) detection. We experimentally demonstrate the strengths and weaknesses of these dynamic race detection techniques in terms of their detection capability, running time, and runtime overhead using 20 benchmark programs with different characteristics. The comparison results show that the detection capability of CP detection does not differ from that of FastTrack, and that SimpleLock+ generates the lowest overhead among the hybrid detection techniques (Acculock, SimpleLock+, and Multilock-HB) for all benchmark programs. SimpleLock+ is 1.2 times slower than FastTrack on average, but misses one true data race reported from Mutilock-HB on the large-scale benchmark programs.

Antioxidative Changes of Blueberry Leaf Extracts in Emulsion-Type Sausage during In Vitro Digestion

  • Hur, Sun-Jin;Kim, Doo-Hwan;Chun, Se-Chul;Lee, Si-Kyung
    • 한국축산식품학회지
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    • 제33권6호
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    • pp.689-695
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    • 2013
  • This study was conducted to investigate the effects of in vitro human digestion on the antioxidant activity of blueberry leaf extracts (BLE) in emulsion-type sausages (ETS). Leaves from four cultivars of blueberries (Bluecrop, Bluegold, Duke, and Northland) collected from a wild blueberry farm were extracted with 80% ethanol. ETS were prepared with 0.2% BLE. The samples were then passed through an in vitro human digestion system which simulates the composition of the mouth, stomach, and small intestine juice. Only one phenolic compound (chlorogenic acid) was detected in the BLE. Northland BLE had appreciably higher amounts of chlorogenic acid than that of other BLE, both before and after in vitro human digestion. Antioxidant activity of any BLE was not influenced by in vitro human digestion, whereas the antioxidant activity of chlorogenic acid standard increased in response to in vitro human digestion in both 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric-reducing ability of plasma (FRAP). In the present study, the antioxidant activities of the BLE were not strongly influenced by in vitro human digestion, and the antioxidant activity depended on the chlorogenic acid content of ETS. Thus, compounds from blueberry leaves may have important applications in the future as natural antioxidants for meat products.

KSR-III 과학탑재 시스템 개발

  • 황승현;김준;전영두;김용하;장민환
    • 항공우주기술
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    • 제1권2호
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    • pp.83-90
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    • 2002
  • 본 논문에서는 3단형 과학관측로켓(KSR-III)에 탑재될 과학탑재부 시스템에 대하여 기술하였다. 과학탑재부에는 크게 오존측정기, 이온층 전자측정기, 대기광도계, 자력계 등이 있으며 선별적으로 탑재되어 한반도 상공의 고층 대기 상태에 대한 연구를 수행할 예정이다. 오존측정기는 한반도 상공의 오존 기둥 밀도를 측정하며 전자측정기는 이온층의 전자밀도와 전자온도를 측정한다. 대기광도계는 중간권의 대기광을 측정하며 자력계는 로켓 자세정보와 로켓이 비행하는 고도에서의 자기장 섭동량을 측정한다. 탑재체들은 현재 개발이 완료된 상태이며 지상 보정 실험도 수행하였으며 각종 환경시험을 통과하였다.

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효율적인 센싱 Coverage를 위한 모바일 센서 네트워크 시뮬레이터 (Mobile Sensor Network Simulator for Efficient Sensing Coverage)

  • 양수현;백성진;박선미;김권환;송은하;박두순;정영식
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2010년도 추계학술발표대회
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    • pp.902-905
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    • 2010
  • 지형의 상태를 정확히 알 수 없는 타겟 지역에 모바일 센서 네트워크를 구축하는 것은 타겟 지역에 필요한 센서 노드의 수, 유지되어야 할 connectivity, 센서 노드들에 의해 타겟 지역이 coverage 되는 비율을 예측 할 수 없기 때문에 그 효율성을 가늠하기가 어렵다. 본 논문에서 설계한 MSNS(Mobile Sensor Network Simulator)는 GML 문서를 통해 실제 지도상의 개체를 가시화 하고 Map Object의 장애물 여부를 설정하여 타겟 지역을 구성한다. 이를 기반으로 MSNS는 센서 노드의 수와 connectivity degree 그리고 센서 노드들의 센싱/통신/초음파 범위를 입력 받아 센서 노드의 현재 위치 정보, connectivity, 센싱 coverage를 가시화 하여 타겟 지역에 얼마나 많은 노드들이 필요한지 유추할 수 있다.

한국 정보화정책의 변천과 특징 - 행위자 연결망을 중심으로 - (A Study on the Changes in and Characteristics of Informatization Policies in Korea: Focusing on the Actor-Network)

  • 한세억
    • 정보화정책
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    • 제17권4호
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    • pp.23-43
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    • 2010
  • 한국의 정보화는 짧은 시간 동안에 커다란 변화를 경험했다. 정보화 정책의 형성과 집행과정에 수많은 인물과 조직이 참여하여 정책의 전개에 영향을 주면서 정보화 정책이 역동적으로 변화하였다. 그러면 국가사회담론으로서 자리 매김한 정보화정책의 확장적 변화와 특성에 영향을 미친 인물이 누구이며, 인적 연결망에 따라 어떠한 변화와 특징을 드러냈는가? 이러한 문제에 대한 해제탐색을 위해 시도된 이 연구의 분석결과, 한국 정보화의 정책전개 및 확장과정에서 정책 관료의 역할이 지배적이었다. 여기에 산업계 및 학계 인사들이 참여하였다. 반면 정치인의 역할은 미약한 것으로 나타났다. 통상 인맥은 학 지 혈연 등에 의해 형성되었지만 정보화정책은 기존의 연(緣)에 의해서라기보다는 정보통신기술을 매개로 한 정책공간에서 형성되었다. 정보통신인맥구성이 이질혼합적임에도 정책줄기가 공고하게 유지될 수 있었던 것은 정보화 중요성, 시급성의 공감대 바탕에서 정보통신기술, 지식과 전문성에 바탕을 둔 연대 또는 유대감이 강하게 작용했기 때문에 가능했던 것으로 판단된다.

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Comparison on Usefulness of Sampling Methods of Indoles in Airs from Swine Facility by Tenax-TA and SPME

  • Yu, Mee-Seon;Lee, Jae-Chun;Yang, Sung-Bong;Kim, Doo-Hwan;Cho, Sung-Back;Whang, Ok-Wha
    • 한국환경과학회지
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    • 제22권12호
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    • pp.1539-1549
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    • 2013
  • The purpose of this study is to compare the sampling methods for monitoring indoles (phenol, p-cresol, indole and skatole) in airs of swine facility. As the collecting methods of indoles in air, Tenax-TA adsorption tube and solid phase microextraction (SPME) were examined. For the preparation of calibration curves of indoles concentrated in Tenax-TA, the standard indoles solutions were spiked in each of Tenax-TA tubes and thermally desorbed (ATD) into a gas chromatograph combined with mass detector (GC/MS). And for the preparation of calibration curves by SPME, indoles in the standard gaseous solution prepared by evaporating the aqueous solution that contained indoles into a polyester sampling bag were extracted with SPME fiber and subsequently analyzed by the GC/MS. Two sampling methods were evaluated for extracting indoles present in swine building environments. Results indicated that the SPME method using Polydimethylsiloxane/ Divinylbenzene (PDMS/DVB) fiber was more effective than Tenax-TA method in extracting indoles. The gas chromatographic analysis showed that the linearities of calibration curves and detection limits were useful for detection of indoles in swine airs. The field tests also showed that considerably different levels of indoles were present in various parts of the swine building.

배추 무사마귀병(Plasmodiophora brassicae)의 발병유인 및 약제방제 (Environmental Factors Favoring the Disease Development and Chemical Control of Clubroot(Plasmodiophora brassicae) in Chinese Cabbage)

  • 오정행;조장환;김봉구;채제천;정길웅;황철호;김두욱
    • 한국식물병리학회지
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    • 제13권4호
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    • pp.244-247
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    • 1997
  • 배추 무사마귀병의 발병에 관여하는 환경요인의 영향을 구명하고 약제처리 방법을 연구한 결과는 다음과 같다. 배추 무사마귀병의 발병율은 근침지접종이나 관주 접종 보다는 전염원 삽입접종에서 현저히 높았다. 발병 유인으로 pH와 온도를 조사한 결과 토양 pH는 5-6에서, 토양온도는 $20-25^{\circ}C$에서 발병율이 높았고 pH 7.0이상, 토양온도 $30^{\circ}C$ 이상에서는 발병율이 급격히 감소하였다. 배추 무사마귀병의 방제를 위해서는 fluazinam 0.5% 분제의 토양살포나 종자분의의 단용처리보다는 둘을 병용처리하는 것이 효과적이다.

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Plant growth promoting rhizobacteria influence potato tuberization through enhancing lipoxygenase activity

  • Akula, Nookaraju;Upadhyaya, Chandrama P.;Kim, Doo-Hwan;Chun, Se-Chul;Park, Se-Won
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2010년도 정기총회 및 추계학술발표회
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    • pp.18-18
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    • 2010
  • Molecular insights on the role of plant growth promoting rhizobacteria (PGPR) in potato tuberization are reported in the present study. The PGPRwere isolated from the soil collected from potato fields of Highland Agricultural Research Centre, Pyeongchang, Korea and they were identified to the genus level based on the 16S rRNA sequence analysis. These PGPR were heat-killed, filtered and the filtrates were addedindividually at a concentration of $10^7\;cfu\;mL^{-1}$ in MS (Murashige and Skoog's) medium supplemented with 7% (w/v) sucrose to study their influence on in vitro potato tuberization. Tuber initiation occurred early in untreated control, while tuber growth was pronounced in case of PGPR treatments. The control explants showed tuber formation as a result of sub-apical swelling of stolons while several sessile tubers formed directly in the axils of nodal cuttings in case of PGPR treatments, which is an indication of strong induction for tuberization. Theexplants cultured on MS medium supplemented with bacterial isolate 6 (Bacillus firmus strain 40) showed highest average tuber yield (Ca. 12.56 g per treatment) after 30 days of culture, which was 3 folds increase over the untreated control. A significant increase in lipoxygenase (LOX1) mRNA expression and activity of LOX enzyme were also detected in the tubers induced on PGPR treatments as compared to untreated control. This LOX expression level correlated with increased tuber growth and tuber yield. Further studies focused on the role of bacteria cell wall components, growth regulators and signal molecules released by PGPR are under investigation to elicit clues for PGPR-mediated signal pathway controlling potato tuberization.

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