• Title/Summary/Keyword: Pilot scale system

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Effect of Hydroxyl Radicals on Photosynthesis Pigments of Phytoplankton in Ship's Ballast Water of 20t/h

  • Bai, Xiyao;Bai, Mindong;Zhang, Zhitao;Bai, Mindi;Yang, Bo
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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    • pp.43-48
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    • 2004
  • A pilot-scale system of 20t/h for the treatment of ship's ballast water and the setup of dissolved hydroxyl radical was introduced in this paper. With this experimental system, the kill efficiencies of bacteria, mono-algae, protozoan reach 100% within 2.67s when dissolved OHㆍconcentration is 0.6mg/L. At the same time, the effect of hydroxyl radicals on the photosynthesis pigments of phytoplankton was done. The results indicate that the contents of chi-a, chl-b, chl-c and carotenoid are decreased to 35~64% within 8.0s further to the lowest limit of test after 5 minutes. When dissolved OHㆍratio concentration is 0.68mg/L, the attenuation efficiencies of photosynthesis pigment are 100%. Therefore the invasive marine species can be killed in the process of the inputting and discharge ship's ballast water.

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다발성감각운동자극 치료가 뇌졸중 환자의 보행과 낙상위험도에 미치는 효과: 무작위배정예비임상시험 (Effect of Multi-Sensorimotor Training on Gait Ability and Fall Risk in Subacute Stroke Patients: A Randomized Controlled Pilot Trial)

  • 임재길
    • 대한통합의학회지
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    • 제7권2호
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    • pp.19-29
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    • 2019
  • Purpose : To determine whether an advanced rehabilitation therapy combined with conventional rehabilitation therapy consisting of sensorimotor exercises that would be superior to a usual treadmill training in gait ability and fall risk in subacute stroke patients. Methods : Thirty subjects randomly assigned to either multi-sensorimotor training group (n=19) or treadmill training group (n=18). Both groups first performed conventional physical therapy for 30 min, after which the multi-sensorimotor training group performed multi-sensorimotor training for 30 min, and the treadmill training group performed treadmill gait training for 30 min. Both groups performed the therapeutic interventions 5 days per week for 8 weeks. Gait ability was evaluated using the GAITRite system and Fall risk was measured using the Biodex Balance system before intervention and after 8 weeks. Results : There were no intergroup differences between demographic and clinical characteristics at baseline (p>.05). Both groups showed a significant improvement in gait ability (p<.05) and Fall risk (p<.05). In particular, the multi-sensorimotor training group showed more significant differences in gait velocity (p=.05), step length (p=.01) and stride length (p=.014) than the treadmill training group. Conclusion : The multi-sensorimotor training program performed on multiple types of sensory input had beneficial effect on gait ability. A large-scale randomized controlled study is needed to prove the effect of this training.

다중 셀 MIMO 네트워크를 위한 Hadamard 행렬 Interstream 전송 기반 Blind 채널 추정 (Blind Channel Estimation based on Hadamard Matrix Interstream Transmission for Multi-Cell MIMO Networks)

  • 양재승;모하마드 아부 하니프;박주용;이문호
    • 한국인터넷방송통신학회논문지
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    • 제15권4호
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    • pp.119-125
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    • 2015
  • 본 논문에서는 다중 셀 MIMO (multiple-input and multiple-output) 네트워크를 위한 Hadamard 행렬 인터스트림 (interstream) 전송기반 blind 채널추정을 소개한다. 제안 방법은 다중 셀로 된 이동 단말 네트워크를 기반으로 연구된다. MS (mobile station) 는 양 셀로부터 신호를 받는 것으로 가정한다. 가까운 셀로부터 받은 신호는 원하는 신호로 간주되고, 다른 셀로부터 받은 신호는 간섭신호로 간주된다. 채널은 blind이기 때문에 채널을 추정하기 위해 Hadamard 행렬 패턴의 파일럿 (pilot) 스트림 (stream) 을 전송하면, 대규모 MIMO 채널에 대해 보다 쉽고 빠른 채널 추정이 가능하게 된다. Hadamard 행렬 기반시스템의 계산은 오직 복소 가산 (complex addition) 만 필요하기 때문에, 복소 승산 (complex multiplication) 이 필요한 Fourier 변환을 이용한 방법보다 복잡도가 훨씬 줄어든다. 수치적 분석을 통해 본 결과 제안한 방법이 완벽함을 보여준다.

농업적 용수재이용을 위한 간헐분사 완속모래여과 하수재처리 효율 평가 (Feasibility Study of Intermittent Slow Sand Filtration for Agricultural Reuse of Reclaimed Water)

  • 윤춘경;정광욱;함종화;황하선
    • 한국농공학회지
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    • 제45권5호
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    • pp.160-170
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    • 2003
  • A pilot study was performed to examine the feasibility of intermittent slow sand filtration for agricultural reuse of reclaimed water. The effluent of biofilter for 16-unit apartment was used as influent to the slow sand filtration system at 0.6 $m^3$/day loading rate using 15 seconds spray in every 10 minutes on the about 1 $m^2$ surface area and 0.5 m depth. The influent concentrations of total coliform (TC), fecal coliform (FC) and E. coli were in the range of 10.000 MPN/100 mL. and they were reduced to less than 1,000 MPN/100 mL after filtration with average of 320, 270, and 154 MPN/100 mL, respectively, showing over 95 % removal. Turbidity and SS were improved effectively and their average concentration was reduced to 0.8 NTU and 1.7 mg/L, respectively, and removal rate was about 50 %. Average BOD and COD concentrations were also reduced substantially to 2.6 and 25.8 mg/L with about 55 and 21 % removal rate, respectively. Nutrients removal was relatively low and removal rate for T-N and T-P was low however, remaining nutrients might be beneficial and less concerned in case of agricultural reuse. The concentration of biofilter effluent used in this experiment was in the range of secondary treatment effluent but slightly stronger than the one from existing wastewater treatment plants (WWTPs). Therefore, intermittent slow sand filtration might be also applicable to the effluent from WWTPs as long as its agricultural reuse is available. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, the intermittent slow sand filtration was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper is a preliminary result from pilot study and further investigations are recommended on the optimum design parameters before full scale application.

축소형 틸트로터 무인기의 안전줄 호버 시험 (Tethered Hover Test for Small Scaled Tilt-rotor UAV)

  • 박범진;유창선;장성호;최성욱;구삼옥;강영신
    • 한국항공운항학회지
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    • 제15권4호
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    • pp.9-16
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    • 2007
  • Tilt rotor aircraft can take off and land vertically and cruise faster than any other helicopter. A scaled flight demonstration model of a tilt rotor aircraft has been developed by KARI. Because the flight characteristics of tilt rotor are not well known, the developed scaled model would be helpful to evaluate flight control algorithm of a full scale aircraft. The tethered hover test has been performed in order to improve hover flight characteristics of tilt rotor aircraft prior to flight test of the small scaled model. During the tethered hover test, the performance of rotor speed governor, rate SAS (Stability Augmentation System) and control surface mixers have been evaluated. We expect that the results of real flight hover test would be quite same as tethered hover test. Therefore the tethered hover test results will reduce the risk of flight test properly by fixing some of hidden problems which might occur during the flight test. This paper presents the results of tethered hover test in detail and shows how it could be final ground test before flight test. The control mixer gain and rate SAS feedback gains were modified in order to get higher controllability and stability during the tethered hover flight. The rotor governor showed that it could keep rotor RPM constant with very small deviation even during severe pilot collective input change. The tethered hover test results gave pilot and engineers confirmation and experience about the scheduled flight test.

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침술의 마약성 진통제 남용 해결을 위한 미국 의료정책 고찰 (Review of US Health Policy on Acupuncture Application for Opioid Abuse Crisis)

  • 김주철;현은혜;김동수
    • 대한한의학회지
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    • 제41권2호
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    • pp.137-149
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    • 2020
  • Background: Opioids are a class of drugs found in the opium poppy, and used primarily as a pain reliever. About 130 people die every day from opioid abuse in the U.S., and the number of deaths was 6 times higher than it was 20 years ago. Objectives: To derive the implications on Korean Medicine(KM), this study aimed to investigate the current state of opioids abuse in the U.S. and analyze cases to solve opioids abuse using acupuncture. Methods: Literature on opioids abuse in the U.S. were searched through the websites of government, agency, and research institute. Results: There were several cases using acupuncture on opioids abuse. First, the Act on the use of acupuncture was enacted. Second, the clinical practice guidelines by the American College of Physicians recommended using acupuncture. Third, a large clinical study was conducted on whether acupuncture could replace opioids. Fourth, Vermont and Washington State conducted pilot projects on insurance coverage of acupuncture. Conclusions: As opioids issues are also valid in Korea, KM can serve a critical role in pain management to pursue expanded insurance coverage. In order to do so, building the discourses of KM in opioid issues is critical by defining its medical advantage, conducting large-scale clinical researches and implementing pilot projects to tackle social problems.

ASBF 생물반응기를 이용한 COD 및 질소 제거특성 (Removal Characteristics of COD and Nitrogen by Aerated Submerged Bio-film(ASBF) Reactor)

  • 최영익;정병길;손희종;성낙창
    • 대한환경공학회지
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    • 제29권9호
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    • pp.997-1002
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    • 2007
  • 본 연구의 목적은 pilot scale ASBF(호기성 침지형 생물막) 반응기를 이용하여 용해성 유기물과 질소화합물의 제거실험을 하였으며, 고정생물막 내에서의 용해성 유기물과 질소화합물 제거를 통한 종속영양미생물 및 독립영양미생물의 동적관계를 이해하고 개선하고자 하였다. 또한, 침지형 생물막 표면에 질산화 박테리아의 성장을 촉진시키기 위해 특별하게 설계한 구조를 라군에 추가하여 폐수처리 효과의 강화 가능성을 조사하였다. 침지형 생물막에 공기 기포가 직접적으로 접촉할 수 있도록 하였으며, 특히 낮은 온도에서 ASBF 실험장치의 용해성 유기물과 암모니아성질소 제거효과를 살펴보기 위해 회분식으로 운전하였다. 본 연구의 ASBF 반응조는 향후 용해성 유기물과 질소화합물의 제거를 위해 기존 폐수처리장 뿐만 아니라 신설 폐수처리장에도 확대 적용될 수 있을 것으로 기대 된다.

효과적인 재원조달을 통한 구도시 u-City 구축사례연구 (A Case Study on the Successful Old-Town u-City Construction by an Effective Financing)

  • 박광호;김명동;김윤형
    • 산업경영시스템학회지
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    • 제35권3호
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    • pp.192-203
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    • 2012
  • As a leading nation of ubiquitous technology, South Korea has been promoting u-City pilot projects throughout the country. According to 'Fundamental Construction Law of u-City,' u-City projects are classified into old-town and new-town types. However, most projects have focused only on the new-town type. Pushing forward large-scale land development projects, Korea Land and Housing Corporation (LH Co.) under Ministry of Land Transport and Maritime Affairs (MLTM) has gained a development profit out of the u-City infrastructure and then donated the infrastructure to a local government without making any plan for operations. In the process of u-City pilot projects, old-towns have been relatively ignored and various of unexpected problems have emerged. Building the u-City of an old-town is not easy due to many constraints such as huge initial investment, long validity and verification procedures, lack of useful services for citizens, lack of professional outsourcing methods for business promotion, high operating costs of the integrated control center, inadequate law related, insufficient institutional requirements and so on. This paper introduces a case study on u-City development for an old-town, Ansan City, as a private investment project. The case will help boost u-City projects for old-towns by solving their problems and providing an effective operational mechanism. As the first BTL (Build-Transfer-Lease) project for constructing u-City, 'Broadband Information Network Development Project' of Ansan City will provide a reference model of expanding u-City projects for other cities.

Discovery of a Radio Relic in the Massive Merging Cluster SPT-CL J2023-5535 from the ASKAP-EMU Pilot Survey

  • Kim, HyeongHan;Jee, M. James;Rudnick, Lawrence;Parkinson, David;Finner, Kyle;Yoon, Mijin;Lee, Wonki;Brunetti, Giangranco;Bruggen, Marcus;Collier, Jordan D.;Hopkins, Andrew M.;Michalowski, Michal J.;Norris, Ray P.;Riseley, Chris
    • 천문학회보
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    • 제45권1호
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    • pp.30.1-30.1
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    • 2020
  • The ASKAP-EMU survey is a deep wide-field radio continuum survey designed to cover the entire southern sky and a significant fraction of the northern sky up to +30°. Here, we report a discovery of a radio relic in the merging cluster SPT-CL J2023-5535 at z=0.23 from the ASKAP-EMU pilot 300 square degree survey (800-1088 MHz). The deep high-resolution data reveal a ~2 Mpc-scale radio halo elongated in the east-west direction, coincident with the intracluster gas. The radio relic is located at the western edge of this radio halo stretched ~0.5 Mpc in the north-south orientation. The integrated spectral index of the radio relic within the narrow bandwidth is α1088MHz800MHz = -0.76 ± 0.06. Our weak-lensing analysis shows that the system is massive (M200 = 1.04 ± 0.36 × 1015M⊙) and composed of at least three subclusters. We suggest a scenario, wherein the radio features arise from the collision between the eastern and middle subclusters. Furthermore, the direct link between the local AGN and the relic along with the discontinuities in X-ray observation hint us that we are looking at the site of re-acceleration.

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소규모 빗물처리시설 개발 및 현장 적용성 평가 연구 (Development of Domestic Rainwater Treatment System and its Application in the Field)

  • 박기정;박민승;김환석;임윤수;김성표
    • 한국습지학회지
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    • 제18권1호
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    • pp.24-31
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    • 2016
  • 도시화에 따른 불투수면 증가로 인한 자연적 물순환 시스템 왜곡 현상과 더불어 불투수면에 축적된 다양한 오염물질은 강우 시 유역 및 하천으로 유입되어 다양한 오염을 일으킨다. 특히 대부분의 강우가 여름철에 집중되는 국내 계절적 특성은 집중호우에 따른 비점오염물질의 수계 과대 유입에 대한 우려를 높이고 있어, 이를 효과적으로 처리하고 재이용하기 위한 다양한 형태의 빗물처리 및 재이용 시설에 대한 연구가 필요하다. 이를 위해 본 연구에서는 강우시 지붕 유출수의 오염특성을 파악하고, 강우 초기 고농도 빗물 유출수를 효과적으로 처리하기 위한 소규모의 빗물정원 포함 형태의 빗물처리시설을 구성하였으며, 처리시설에 포함된 빗물정원에서의 오염물질 처리 효율을 높이기 위해 실험실 규모의 인공강우를 이용한 다양한 여재 구성 오염물질(TN, TP, CODcr) 제거율 실험을 실시하였다. 이를 통해 제거효율이 가장 높은 피트머스(Peatmoss)와 자갈, 모래를 구성된 빗물정원을 시범유역에 설치하여 오염물질 제거효율을 측정하였다. 2015년 6월 ~ 7월까지 4회의 실제 강우에 대한 강우사상별 시간별, 강우사상별, 농도별 오염물질 제거율을 분석 한 결과 강우강도가 높거나 강우량이 커질수록 고농도의 오염물질이 빗물처리시설 내 빗물정원으로 유입되었으며, 분석 결과 오염물질의 제거율은 저농도 일 때 보다 고농도 일 때 더 높은 것으로 나타났다. 대규모의 빗물처리시설을 설치하기 어려운 도심지에서, 위와 같은 소규모 시설을 효과적으로 활용 한다면, 도시 유역에서 강우시 발생하는 초기세척효과에 의한 비점오염 형태의 오염물질 유입을 차단해 오염물질 부하를 저감하는데 효과적으로 활용 될 수 있을 것으로 판단되며, 나아가 도서 지역내 용수공급을 위한 소규모 재이용 시설로도 활용 가치가 있을 것으로 판단된다.