• 제목/요약/키워드: BED

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소류사량에 관한 연구 (A Study on the Bed-Load Transport Rate)

  • 강주복;정연태;김원규
    • 물과 미래
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    • 제22권2호
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    • pp.191-200
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    • 1989
  • 소류사의 입자이동속도와 소류사농도의 곱으로 소류사량을 계산할 수 있는 한 방법이 제시되었다. 본 연구에서 사립의 평균이동속도는 하상부근의 유속난류성분의 출현빈도가 정규분포 한다고 가정하고, 입자이동속도를 소류력의 함수와 하상부근의 평균유속의 곱으로 나타내었다. 소류사에 유효하게 작용하는 소류력을 구하기 위해서 Engelund가 제시한 식을 사용하여 유효마찰속도를 구하였으며 Engelund가 제시한 식의 적합성을 간접적으로 검증했다. 소류사농도를 구하기 위해서 호전·도상의 식을 사용하였다. 실험자료는 타 연구자들의 식과 비교되었으며 타 연구자들의 식과 비슷한 경향을 나타내었다. 소류력이 비교적 작은 경우를 제외하고 제시된 식에서 계산된 결과와 타연구자들의 자료는 잘 일치하였다.

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표고골목의 화학적 특성과 펄프재로서의 이용방안 (Chemical Characteristics and Application for Kraft Pulp of Bed Log Wastes)

  • 정명준;김대영;조병묵;오정수
    • Journal of the Korean Wood Science and Technology
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    • 제33권3호통권131호
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    • pp.79-88
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    • 2005
  • 연구는 폐표고목을 제지용 원료로 활용하기 위한 기초자료로 1년부터 5년 동안 재배한 표고골목을 이용하여 목재 성분 조성과 크라프트 펄프화 특성을 평가하였다. 그 결과 화학조성의 경우 변재에서는 재배기간이 증가함에 따라 글루코스와 자일로스의 감소가 크게 나타났으나 심재부에서는 큰 차이가 나타나지 않았으며 정선수율과 리젝트 함량 모두 재배기간이 증가함에 따라 감소하였다. 펄프 특성에서도 재배기간 증가에 따라 섬유장과 폭, 여수도는 감소하였으며 폐표고골목 크라프트 펄프를 국산 폐골판지에 첨가 시 종이의 건조 강도가 향상되었다. 이상의 결과로 폐표고목 크라프트 펄프를 다른 장섬유 펄프와 혼합사용 시 강도 향상과 고해 에너지 감소를 기대할 수 있을 것으로 사료된다.

Characterization of the Effects of Relative Humidity and Bed-depth on $CO_2$ Capture for Maximizing the Utilization Rate of Soda Lime Sorbent

  • Cho, Il-Hoon;Park, Guen-Il;Kim, Joon-Hyung;Hwang, Taek-Sung;Lee, Mi-Kyoung
    • Carbon letters
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    • 제2권2호
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    • pp.113-119
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    • 2001
  • The advanced method for $CO_2$capture is currently one of the most important environmental issues in worldwide and it is therefore necessary to have available technologies, which minimize the discharge of $CO_2$ including Carbon-14 from nuclear facilities into the atmosphere. A key aspect of this work is to provide the technically principal data required to improve a $CO_2$ removal system for the utilization of regenerative sorbent use, specifically include suggestions regarding its modified column design (parallel dual-bed assembly), stop-restart operation and the economic feasibility of sorbent use. The removal performance of soda lime and the effects of relative humidity (RH) and packing bed-depth (BD) on $CO_2$ removal were investigated. In a single-bed, it revealed that the utilization of soda lime for $CO_2$ removal at line velocity of 13 cm/sec and bed depth of 12 cm increased with the increased relative humidity up to 85%. However, in the parallel dual-bed assembly applied with the stop-restart operation, a maximum utilization rate of soda lime for $CO_2$ removal was obtained even at 55% of RH and 8 cm of BD, specifically the utilization rate of soda lime by using this $CO_2$ removal assembly was about two-fold superior to that in a single-bed.

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Packed-Bed 반응기를 이용한 한천올리고당의 연속생산 (Continuous Production of Agarooligosaccharides Using Packed-Bed Reactor)

  • 임동중;김종덕;강양순;공재열
    • KSBB Journal
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    • 제16권4호
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    • pp.398-402
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    • 2001
  • 본 연구에서는 고정화된 한천분해효소가 충진된 packed-bed reactor를 이용하여 한천올리고당을 연속생산하였다. Packed-Bed 형 Reactor의 H/D를 조절하여 생산율이 가장 좋은 조건을 살펴 본 결과, H/D=14인 것으로 나타났으며, 한천올리고당의 연속생산시 35 h에서 효소활성반감기를 나타내었다. Packed-Bed Reactor내에서 기질 1 g/L agar, 1unit 고정화효소, 4$0^{\circ}C$, flow rate 24 mL/min 조건하에서 연속반응 시켰을 때, 중합도 4의 한천올리고당이 주로 생산되었으며 중합도 6당, 2당순으로 생산됨을 알 수 있었다. 또한 다중으로 연결된 반응기를 이용한 결과, 기질 1 g/L agar, 4$0^{\circ}C$, 48 mL/min의 조건하에서 41.7 mg/h의 한천올리고당이 생산됨으로서 다중으로 연결하지 않은 반응기보다 2.3배 한천올리고당의 생산율이 증가하였음을 알 수 있었다.

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도심지 토사재해 방어기술 테스트베드 구축 및 모니터링 연구 (Construction and Monitoring of Test bed in Urban Sediment Disaster Prevention Technology)

  • 이정민;김효진;이윤상;진규남
    • 토지주택연구
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    • 제8권3호
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    • pp.161-169
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    • 2017
  • In this study, sediment transfer and precipitation analysis of the test bed watershed was conducted through the model for the application and practical use of the urban sediment disaster prevention technology, and used this as an aid to design to secure reliability. In addition, conducted the test bed monitoring with the defense technology, analyzed the effect, and established the maintenance plan. Analyzed the change of soil deposition volume through arbitrary slope adjustment for the currently installed stormwater conduit of the test bed watershed. As a result, it is important to reduce the total sedimentation amount in the adjustment of the slope of the entire pipeline, but it is important that the sedimentation depth of each sediment does not rise to such a degree as to threaten the performance of the pipeline. Considering these matters, it is necessary to design the pipeline to prevent the clogging of the soil from the viewpoint of the reliability of the entire pipeline. The sediment disaster defense technology test bed is divided into a new city and an old city, and old city test bed is under construction. The result obtained through the monitoring of the test bed in the new city, sediment disasters such as debris can delay the time to reach the downtown area, and it is possible to secure the golden time, such as evacuation and rescue through the warning system. Also, the maintenance of the test bed application was suggested. Continuous and systematic monitoring is required for securing the reliability of element technology and successful commercialization.

Species identification and pyrethroid resistance genotyping of recently resurgent Cimex lectularius and Cimex hemipterus in Korea

  • Susie Cho;Heung Chul Kim;Hoonsik Eom;Jae Rok Lee;Chung Hyun Ko;E-hyun Shin;Won Kyu Lee;Si Hyeock Lee;Ju Hyeon Kim
    • Parasites, Hosts and Diseases
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    • 제62권2호
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    • pp.251-256
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    • 2024
  • The global resurgence of bed bug infestations, exacerbated by increasing international travel, trade, and insecticide resistance, has significantly impacted Korea. This study identified the bed bug species and performed pyrethroid resistance genotyping of recently resurgent bed bugs in Korea. Thirty-one regional bed bug samples were collected from 5 administrative regions: Gyeonggi-do (n=14), Seoul (n=13), Busan (n=2), Jeonllanam-do (n=1), and Chungcheongbuk-do (n=1). The samples underwent morphological and molecular identification. Twenty-four regional samples (77.4%) were identified as the tropical bed bug, Cimex hemipterus, and the remaining 7 regional samples (22.6%) were identified as the common bed bug, Cimex lectularius. The C. hemipterus regional samples carried at least three mutations associated with knockdown resistance (kdr), including 2 super-kdr mutations. The 7 C. lectularius regional samples possessed at least one of the 3 kdr-related mutations associated with pyrethroid resistance. This study confirms that the prevalent bed bug species recently in Korea is C. hemipterus, replacing the previously endemic C. lectularius. Additionally, the rise in bed bug populations with pyrethroid resistance underscores the necessity of introducing alternative insecticides.

The Effect of a Bed-Backrest Elevation System Combined With Hip and Knee Flexion on Lower Extremity Body-Pressure Reduction

  • Kim, Min-Hee;Yoo, Won-Gyu;Yi, Chung-Hwi;Kim, Han-Sung;Kim, Su-Jin
    • 한국전문물리치료학회지
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    • 제15권4호
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    • pp.59-63
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    • 2008
  • Pressure sores are painful and needless complications of critical illness. and manifest as a localized area of ischemic necrosis of tissue caused by pressure. This study analyzed the bed-backrest elevation system combined with hip and knee flexion for lower extremity lower pressure reduction. Eight healthy adults aged 21 to 26 years were recruited. The Body Pressure Measurement Mat of the TekScan system was used to measure the location and magnitude of the peak pressures on the body bed interface. The SPSS statistical package was used to analyze the significance of differences between the general bed-backrest elevation system and the bed-backrest elevation system combined with hip and knee flexion using the paired t-test. The result showed that the body-pressure of the lower extremity was more significantly reduced for the bed-backrest elevation system combined with hip and knee flexion ($26.6{\pm}4.3$ mmHg) than a general bed-backrest elevation system ($37.3{\pm}5.2$ mmHg) (p<.05).

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수직 흐름 제올라이트 갈대 여과상의 간헐적 주입에 의한 인공하수 처리 (Vertical Flow Zeolite-Filled Reed Bed for Treatment of Artificial Sewage with Intermittent Feeding)

  • 서정윤;김태형;최민수
    • KSBB Journal
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    • 제18권2호
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    • pp.140-144
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    • 2003
  • 제올라이트로 충진된 수직 흐름 갈대 여과상에 인공하수를 주입하면서 처리효율을 조사하였다. 여과상 표면적 $m^2$당 1일 314 L의 인공하수가 6시간마다 10분 동안 간헐적으로 주입되었다 각 항목별 연중 평균 처리효율은 CO $D_{Cr}$ , 95.1%, T-N 49.5%, N $H_4$$^{+}$-N 99.4%, T-P 56.4%이었다. T-N의 처리효율은 가동 시간이 경과함에 따라 현저하게 감소하였다. 여과상의 상층에서 많은 인이 흡착되었으며 흡착된 인 중 대부분은 Fe-p, Ca-P와 환원가용성 Fe-P이었다.

U-City의 성공적 구현을 위한 테스트베드 기본계획의 기준 수립에 관한 연구 (A Study on the Standard Establishment of Test-Bed Master Plan for Successful Realizations of U-City)

  • 이재용;피민희;정주영;신동빈
    • Spatial Information Research
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    • 제18권1호
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    • pp.1-10
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    • 2010
  • 최근 많은 R&D 사업에서는 연구개발 완료 후, 연구 성과물들을 검증하기 위한 테스트베드사업이 다양하게 추진되고 있으나 일관적이고 체계성 있는 기준이 설정되어 있지 않은 실정이다. 따라서 본 연구에서는 체계적인 U-City 테스트베드 구축을 위해 기본계획의 기준을 도출하고, 도출된 기준에 근거하여 청라지역을 사례로 U-Eco City 테스트베드 기본계획(안)을 수립하여 검증하고자 한다. 이와 같이 설정된 U-City 테스트베드 기본계획 기준을 통해 테스트베드 특성에 맞는 체계화되고 합리적인 테스트베드 구축이 진행될 수 있을 것이다.

간동맥 화학색전술을 시행 받은 환자에게서 4시간 절대침상안정 후 조기 이상의 효과 (The Effect of Early Ambulation after 4 Hours of Bed Rest in Patients with Transarterial Chemoembolization)

  • 남선희;김영주
    • 성인간호학회지
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    • 제28권1호
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    • pp.53-60
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    • 2016
  • Purpose: This study was to compare the effects of early ambulation to usual care of late ambulation in patients with transarterial chemoembolization on back pain, discomfort, and puncture site complications. Methods: A nonequivalent control pretest-posttest design was used. Total 40 patients were recruited from a gastrointestinal unit of an urban general hospital in Seoul, South Korea. The experimental group began to ambulate after 4 hours of bed rest with a compression bandage after receiving transarterial chemoembolization. The control group stayed in bed with a compression bandage overnight. Results: Back pain was not significantly different between the two group. The experimental group reported significantly lower discomfort than the control group. There was no incidence of bleeding complications on puncture site between two groups. Conclusion: The results of this study showed that early ambulation with four hours of bed rest after femoral sheet removal did not cause bleeding complications compared to the usual care and even decreased patients' level of discomfort due to bed rest. Repetitive research on the effect of short bed rest is warranted for its clinical utilization.