• Title/Summary/Keyword: 수용면적

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Characteristics of the Sinusoidal Flux Continuous Operation Mode for the Submerged Flat-sheet Membrane Module in Cutting Oil Solution (절삭유 수용액내 침지식 평막 모듈에 대한 사인파형 투과유속 연속운전 방식의 특성)

  • Won, In Hye;Chung, Kun Yong
    • Korean Chemical Engineering Research
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    • v.53 no.5
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    • pp.646-652
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    • 2015
  • In this study transmembrane pressure (TMP) was measured with respect to permeate flux through the submerged flat sheet membrane for the emulsion and semi-synthetic cutting oil solutions. The effective area and nominal pore size of the used microfiltration membrane were $0.02m^2$ and $0.15{\mu}m$, respectively. The experiments were carried out simultaneously for run/stop (R/S) and sinusoidal flux continuous operation (SFCO) modes using two submerged membrane module in the reservoir. TMP for the case of SFCO was maintained under 60% of R/S, and the effect on TMP drop decreased as the permeate flux increased for emulsion cutting oil solution. Membrane fouling for the semisynthetic solution showing low turbidity was induced lower comparing to the emulsion solution. Also, the effect on TMP drop for SFCO decreased during long-term operation.

Effects of flower removal on Growth and Content of essential oil in Atractylodes macrocephala Koidz (화기제거가 백출(Atractylodes macrocephala Koidz)의 생육 및 정유 함량에 미치는 영향)

  • 김수용;권오흔;조지형;임재하
    • Korean Journal of Plant Resources
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    • v.14 no.2
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    • pp.152-156
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    • 2001
  • This study was conducted to investigate the flower organ removal effect on Atractylodes macrocephala Koidz which was introduced from China. The results were summarized as follows; The plant height of Flower Organ Cutting(F.O.N.C.) treatment short by 1.7∼2.5 cm compared to Flower Organ Non-Cutting(F.O.N.C.) treatment. But number of stem and stem diameter of F.0.C treatment were similar to that of F.O.N.C. treatment. The fresh weight of above-ground part of F.O.N.C. treatment was decreased 48∼60% compare to F.O.C. treatments. The later was period of F.O.C., the higher was fresh weight of above-ground part. The growth of underground part was more F.O.C. at July 15 and Aug. 20 treatments than F.O.N.D treatment. The dry rhizome yield of F.O.C. at July 15 treatment was increased 40% compare to F.O.N.D treatment. Essential oil content of F.O.C. at July 15 treatment was increased 12% compare to F.O.N.D treatment.

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Analyzing the Location of Urban Neighborhood Parks Using GIS and AHP Techniques (GIS와 AHP 의사결정 방법을 이용한 도시 근린 공원의 입지 분석)

  • 홍성언;박수홍
    • Journal of the Korean Geographical Society
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    • v.38 no.5
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    • pp.849-860
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    • 2003
  • City's inhabitants should be able to utilize a variety of urban infrastructures and public facilities in a way of possessing the convenience, amenity, and safety of urban life. Most of the city government, however has established a policy for making and providing urban park facilities based on a very simple quantitative criteria rather than the qualitative criteria such as appropriateness, utility, accessibility, equity so far. Especially in the case of urban neighborhood parks, the usefulness to the inhabitant and accessibility to the parks may be questionable. In this study, we intended to analyze the spatial equity and distribution characteristics of urban neighborhood parks and to select several potential facility sites required in the study area using GIS's spatial analysis functions. Finally this study analyzes the possible location of an urban neighborhood park in terms of objective criteria and AHP techniques.

Treatment of hazardous chemicals by Nanoscale Iron powder (나노크기 철 분말을 이용한 난분해성 유해화합물질의 처리)

  • 최승희;장윤영;황경엽;김지형
    • Journal of Korea Soil Environment Society
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    • v.4 no.3
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    • pp.85-93
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    • 1999
  • The destruction of hazardous chemicals such as chlorinated organic compounds(COCs) and nitroaromatic compounds(NACs) by zero-valent iron powder is one of the latest innovative technologies. In this paper. the rapid dechlorination of chlorinated compounds as well as transformation of nitro functional group to amine functional group in the nitroaromatic compounds using synthesized zero-valent iron powder with nanoscale were studied in anaerobic batch system. Nanoscale iron, characterized by high surface area to mass ratios(31.4$\textrm{m}^2$/g) and high reactivity, could quickly reacts with compounds such as TCE, chloroform, nitrobenzene, nitrotoluene, dinitrobenzene and dinitrotoluene, at concentration of 10mg/L in aqueous solution at room temperature and pressure. In this study, the TCE was dechlorinated to ethane and chloroform to methane and nitro groups in NACs were transformed to amino groups in less than 30min. These results indicated that this chemical method using nanoscale iron powder has the high potential for the remediation of soils and groundwater contaminated with hazardous toxic chemicals including chlorinated organic compounds and nitro aromatic compounds.

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Study on the Spatial Standard for Reading Rooms in University Libraries (대학도서관 열람실 공간기준에 관한 연구)

  • Lim, Ho-Kyun
    • Korean Institute of Interior Design Journal
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    • v.25 no.5
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    • pp.140-147
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    • 2016
  • This research aims to establish the size standard of university library's user space, and present the standard and method to calculate total area required in the planning of new building construction and remodeling. Nine university libraries newly constructed or remodeled since 2000 were selected among the libraries of large scale universities with more than 10,000 enrolled students as the target libraries in this research. The target libraries were classified into A group (five cases partially remodeled) and B group (four cases newly constructed or fully remodeled) on the basis of the change of times. A university library can be divided into three spaces (user space, administration space and public space). This research classified the reading room in the user space into bookshelf zone, reading zone, information/office zone and hall/other zone, and analyzed area ratio according to each zone. B group's bookshelf zone decreased 12% more than A group, and B group's reading zone increased 10% more than A group. However, there was no big change in the area ratio of information/office zone and hall/other zone. This can be interpreted that university library changes from book and archive preservation-oriented space to user-oriented space. This research presented a proper reading room area calculation method, based on the capacity of books, by reflecting such a change. Each zone's standard was set up through classification of domestic and international standards, based on which, the calculation method of university library's total floor area required was presented. The reason why there was difference in university library's total floor area required according to domestic standard and international standard was that the number of enrolled students per seat in the reading room was different. The area calculation methods presented in this research can be utilized as useful data upon planning university library construction or remodeling.

Position of Stop Line according to the Left Turn Trajectory at Intersection (교차로 좌회전 궤적에 따른 정지선 위치에 관한 연구)

  • 김기용;김동녕
    • Journal of Korean Society of Transportation
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    • v.18 no.3
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    • pp.29-39
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    • 2000
  • Position of stop line according to left turn trajectory at intersections was studied. The Purpose of this study is to suggest a design guideline of left turn trajectory at intersections which is related to the Position of cross road stop line. Distance from the curb line to the stop line at each lane was calculated and discussed for various combination of road widths. Three design vehicle type and three control radii were considered. Setbacks of stop line from the curb line are Proportional to the control radius which depends on type of design vehicle. 8m, lim and 19m setback for control radius of 12m, 15m and 23m were calculated respectively as their maximum value. This result will be helpful to Paint the road marking on the Pavement which is usually difficult to fit to the designated radius. Field study of the effect of left turn trajectory on flow rate and safety was conducted. It was approved that improperly designed left turn trajectory decreases left turn capacity and increases conflicts among left turn flows of the adjacent lane.

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A Low Power Antenna Switch Controller IC Adopting Input-coupled Current Starved Ring Oscillator and Hardware Efficient Level Shifter (입력-결합 전류 제한 링 발진기와 하드웨어 효율적인 레벨 시프터를 적용한 저전력 안테나 스위치 컨트롤러 IC)

  • Im, Donggu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.1
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    • pp.180-184
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    • 2013
  • In this paper, a low power antenna switch controller IC is designed using a silicon-on-insulator (SOI) CMOS technology. To improve power handling capability and harmonic distortion performance of the antenna switch, the proposed antenna switch controller provides 3-state logic level such as +VDD, GND, and -VDD for the gate and body of switch of FETs according to decoder signal. By employing input-coupled current ring oscillator and hardware efficient level shifter, the proposed controller greatly reduces power consumption and hardware complexity. It consumes 135 ${\mu}A$ at a 2.5 V supply voltage in active mode, and occupies $1.3mm{\times}0.5mm$ in area. In addition, it shows fast start-up time of 10 ${\mu}s$.

Image Edge Detector Based on a Bump Circuit and the Neighbor Pixels (Bump 회로와 인접픽셀 기반의 이미지 신호 Edge Detector)

  • Oh, Kwang-Seok;Lee, Sang-Jin;Cho, Kyoungrok
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.7
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    • pp.149-156
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    • 2013
  • This paper presents a hardware edge detector of image signal at pixel level of CMOS image sensor (CIS). The circuit detects edges of an image based on a bump circuit combining with the pixels. The APS converts light into electrical signals and the bump circuit compares the brightness between the target pixel and its neighbor pixels. Each column on CIS 64 by 64 pixels array shares a comparator. The comparator decides a peak level of the target pixel comparing with a reference voltage. The proposed edge detector is implemented using 0.18um CMOS technology. The circuit shows higher fill factor 34% and power dissipation by 0.9uW per pixel at 1.8V supply.

Throughput Analysis of Non-Transparent Mode in IEEE 802.16j Mobile Multi-Hop Relay Networks (IEEE 802.16j MMR 네트워크에서 Non-Transparent 중계모드의 전송률 분석)

  • Lee, Ju-Ho;Lee, Goo-Yeon;Jeong, Choong-Kyo
    • Journal of the Korea Society for Simulation
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    • v.21 no.2
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    • pp.51-58
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    • 2012
  • In IEEE 802.16j MMR protocol, two modes about usage of RS are proposed; one is transparent mode to enhance data throughput and the other is non-transparent mode to extend coverage. In this paper, we focus on non-transparent mode and find that the mode can also improve data throughput. Therefore, we analyze data throughput on various RS topology and their extended coverage area by simulation in IEEE 802.16j non-transparent mode. We also compare the simulation results with the single MR-BS system of which coverage is extended by higher transmission power. From the comparisons of simulation results, we see that higher throughput can be obtained in the proposed non-transparent mode.

Evaluation of the Bioequivalence of Two Brands of Naltrexone 50 mg Tablet in Healthy Volunteers

  • Baek, In-Hwan;Yun, Hwi-Yeol;Kang, Won-Ku;Kwon, Kwang-Il
    • Korean Journal of Clinical Pharmacy
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    • v.16 no.1
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    • pp.69-74
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    • 2006
  • 날트렉손은 ${\mu}-opioid$ 수용체에 특이적이고 선택적으로 길항작용을 나타내어 마약이나 마약성 진통제의 강한 의존성 치료에 쓰일 뿐만 아니라, 알코올 의존성 치료에도 쓰이는 약물이다. 본 연구는 날트렉손 제제인 레비아 정 (50 mg tablet, 제일약품) 을 대조약으로 하여 시험약인 명인 제약의 트락손 50 mg정의 생물학적 동등성 평가를 하기 위해 22명의 건강한 지원자를 모집하였다. 지원자를 두 군으로 나누어 1정씩 투여하였고 $2{\times}2$ 교차시험을 실시하였다. 날트렉손의 혈장 중의 농도를 정량하기 위하여 발리데이션된 LC/MS/MS를 사용하였다. 채혈 시간은 투약 전 및 투약 후 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 9, 12 시간에 걸쳐 시행하였다. 생물학적 동등성을 판정하기 위한 파라미터로 12시간까지의 혈장 중 농도 곡선 하 면적$(AUC_{12hr})$과 최고 혈중 농도 $(C_{max})$를 사용하였다. $AUC_{12hr}$의 평균은 $43.45ng{\cdot}hr/ml$ (시험약)과 $43.31ng{\cdot}hr/ml$ (대조약) 으로 관찰되었고, $C_{max}$의 경우 각각 12.01 ng/m1 (시험약)과 12.27 ng/ml (대조약)으로 관찰되었다. $AUC_{12hr}$의 경우 로그변환 한 평균치 차의 90%의 신뢰구간이 log0.95-log1.07이었고, $C_{max}$의 경우 log0.87-log1.14로 계산되어 두 항목 모두 log0.8-log1.25이어야 한다는 식품의약품 안전청과 FDA의 기준을 모두 만족시켰다. 이상의 결과를 종합하면 시험약 트락손 정 50mg 은 대조약 레비아 정 50 mg에 대하여 생물학적으로 동등한 것으로 판정되었다.

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