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Bathymetric changes off the sea south of Jinwoo-do Island in the Nakdong River estuary (낙동강 하구역 진우도 남측 해역의 해저지형 변화)

  • Park, Bong-woon;Kim, Sung-bo;Kim, Jae-joong;Kim, Ki-cheol
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.1
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    • pp.69-74
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    • 2016
  • Bathymetric changes were studied in the southern sea off the Jinwoo-do Island, which is one of the deltaic barrier islands surrounding the Nakddong river estuary. In this study, 16 bathymetry data sets were obtained from June 2006 to April 2015. Two narrow channels, the one lying between Jinwoo-do and Shinja-do, and the other one lying between Nulcha-do and Jinwoo-do extended into the eastern and western parts of the study area, respectively. The eastern extension of the channel contained a passage of mixed estuarine waters of seawater and river water discharged from the Nakdong river barrier and the west Nakdong River. The western channel connected the Nakdong River estuary with the Busan New Port via a connecting pier. Total volumetric changes of sediments in study area and discharge flow of the Nakdong river barrier were analyzed. Bottom topographical changes occurred mainly in the eastern extension of the channel. These changes were initially characterized by gradual erosion or deposition followed by rapid restoration. The total volume of sediment gradually increased from June 2006 to March 2013, but experienced a sudden decrease in October 2013 because of typhoon Danas. Few fluctuations were observed from October 2013 to April 2015. Analysis of the cross-sectional bathymetry of the north-south direction showed that the deepest point of the eastern channel moved 100-130 m westward and 200 m northward between June 2006 and April 2015.

Seismic AVO Analysis, AVO Modeling, AVO Inversion for understanding the gas-hydrate structure (가스 하이드레이트 부존층의 구조파악을 위한 탄성파 AVO 분석 AVO모델링, AVO역산)

  • Kim Gun-Duk;Chung Bu-Heung
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.643-646
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    • 2005
  • The gas hydrate exploration using seismic reflection data, the detection of BSR(Bottom Simulating Reflector) on the seismic section is the most important work flow because the BSR have been interpreted as being formed at the base of a gas hydrate zone. Usually, BSR has some dominant qualitative characteristics on seismic section i.e. Wavelet phase reversal compare to sea bottom signal, Parallel layer with sea bottom, Strong amplitude, Masking phenomenon above the BSR, Cross bedding with other geological layer. Even though a BSR can be selected on seismic section with these guidance, it is not enough to conform as being true BSR. Some other available methods for verifying the BSR with reliable analysis quantitatively i.e. Interval velocity analysis, AVO(Amplitude Variation with Offset)analysis etc. Usually, AVO analysis can be divided by three main parts. The first part is AVO analysis, the second is AVO modeling and the last is AVO inversion. AVO analysis is unique method for detecting the free gas zone on seismic section directly. Therefore it can be a kind of useful analysis method for discriminating true BSR, which might arise from an Possion ratio contrast between high velocity layer, partially hydrated sediment and low velocity layer, water saturated gas sediment. During the AVO interpretation, as the AVO response can be changed depend upon the water saturation ratio, it is confused to discriminate the AVO response of gas layer from dry layer. In that case, the AVO modeling is necessary to generate synthetic seismogram comparing with real data. It can be available to make conclusions from correspondence or lack of correspondence between the two seismograms. AVO inversion process is the method for driving a geological model by iterative operation that the result ing synthetic seismogram matches to real data seismogram wi thin some tolerance level. AVO inversion is a topic of current research and for now there is no general consensus on how the process should be done or even whether is valid for standard seismic data. Unfortunately, there are no well log data acquired from gas hydrate exploration area in Korea. Instead of that data, well log data and seismic data acquired from gas sand area located nearby the gas hydrate exploration area is used to AVO analysis, As the results of AVO modeling, type III AVO anomaly confirmed on the gas sand layer. The Castagna's equation constant value for estimating the S-wave velocity are evaluated as A=0.86190, B=-3845.14431 respectively and water saturation ratio is $50\%$. To calculate the reflection coefficient of synthetic seismogram, the Zoeppritz equation is used. For AVO inversion process, the dataset provided by Hampson-Rushell CO. is used.

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Analysis of Recent Trends on the Experimental Studies in Acupuncture and Moxibustion Papers (침구관련 실험연구 논문 동향 분석)

  • Han, Kyung-Ju;Hwang, Hye-Suk;Kim, Yu-Sung;Lee, Ji-Eun;Jeong, Sang-Yong;Ryu, Yeon-He;Choi, Sun-Mi;Koo, Sung-Tae
    • Korean Journal of Oriental Medicine
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    • v.13 no.2 s.20
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    • pp.83-90
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    • 2007
  • The aim of the study was to analyze recent trends of experimental studies regarding to acupuncture and moxibustion (AM) through reviewing the 492 papers in the PubMed database in order to help researchers from overlapping study on the same theme and to spur them to investigate experimental studies on AM with understanding the current flow of that. For the analysis, we include papers in which abstract was written in English. First, we performed quantitative analysis of the experimental studies using whole of the first filtrated 492 papers. From this analysis, we could obtain the followings: 'Trends of study in the most frequently appeared journals and leading authors in experimental study of AM'. 'The number of papers and name of journals by leading authors in experimental study of AM'. 'Trends of Korean papers in the most frequently appeared journals and Korean leading authors in experimental study of AM", 'Classification of experimental studies related to acupuncture and moxibustion according to intervention methods or individual country' and 'Assortment of experimental studies related to acupuncture and moxibustion in terms of intervention methods on leading countries'. Second, we collected 72 papers considering impact factor of the journal and influential effect of the papers' result for qualitative analysis, and we divided the papers into pain related one or not, because the effect of AM on pain is major subject of AM study. The results showed that experimental studies regarding to AM still has several weakness such as limited usage of acupuncture points and inclined application of electroacupucture even though there are 361 acupuncture points in the human body and various kinds of stimulation methods using traditional needles and moxibustion. Therefore, we suggest that researchers should pay more attention to the study on basic AM research creatively and systematically through strengthening and enhancing the cooperation among colleges, research institutes and hospitals. Moreover, in order to promote the basic research of the AM, it is required that we need cross-disciplinary research as well as international collaboration research.

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Fabrication of Small SOFC Stack Based on Anode-Supported Unit Cells and Its Power Generating Characteristics (음극지지형 단전지를 사용한 소형 SOFC 스택의 제조 및 출력특성)

  • Jung, Hwa-Young;Kim, Woo-Sik;Choi, Sun-Hee;Kim, Joosun;Lee, Hae-Weon;Ko, Haengjin;Lee, Ki-Chun;Lee, Jong-Ho
    • Journal of the Korean Ceramic Society
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    • v.41 no.10 s.269
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    • pp.777-782
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    • 2004
  • In this research, $5\times5cm^2$ unit cells were fabricated via liquid condensation process and uniaxial pressing followed by the screen printing of electrolyte and cathode layer. The SOFC stack was assembled with unit cells, gasket-type sealant and metal interconnect. The stack was designed to have a single column with internal-manifold and cross-flow type gas-channels. The SOFC stack produced 15 W, which is $50\%$ of the maximum power being expected from the maximum power density of the unit cell. Controlling factors for the proper operation of the SOFC stack and other designing factors of stack manifold and gas channels were discussed.

Long-term Relative Humidity Changes on High Temperature Days of Major Cities in Korea for the Recent 37 Years (최근 37년간 우리나라 주요도시의 고온일을 대상으로 한 상대습도의 경년변화)

  • Park, Myung-Hee;Lee, Joon-Soo;Suh, Young-Sang;Han, In-Seng;Hae, Hyun-Gun;Kim, Hae-Dong
    • Journal of Environmental Science International
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    • v.22 no.12
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    • pp.1671-1681
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    • 2013
  • The study selected 10 regions among major Korean cities. Then the study classified the yearly change of relative humidity of those regions for 37 years based on 1996 (from 1974 to 2011) aimed at high temperature days, and examined them by stage regarding daily maximum temperature. For large cities and small cities, in general relative humidity had been likely to increase at high temperatures of $30^{\circ}C$ or over before 1996, whereas it has decreased since 1996. For suburban areas, relative humidity had been prone to diminish before 1996, whereas it has been likely to either increase since 1996 or rarely some of the cities have not shown any change. The increasing tendency of relative humidity before 1996 in large cities and small cities is believed to be because of an increase of the latent heat of vaporization by the supply of steam from cooling towers established in downtown areas. Meanwhile, the decreasing tendency from 1996 is concluded to be caused by the change from counter-current circular cooling towers, which produce a great quantity of steam including arsenic acid, to cross-flow cooling towers, which produce hardly any steam containing arsenic acid. This change was in accordance with the modification and pursuit of an urban planning law that ordered cooling towers that had been installed on rooftops be installed in the basement of buildings in consideration of a "Green network creation" project by the Ministry of Environment, urban beautification, concerns since 1996 over building collapses, and according to an argument that steam containing arsenic acid could be harmful to human health owing to chemicals contained in the water in the cooling tower in summer.

Climatological Boundary and Characteristics of Coastal Zone over the Southwestern Korean peninsula (한반도 남서해안의 기후학적 연안지대의 경계와 특징)

  • 이영선;하경자;전은희
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.9 no.3
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    • pp.137-152
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    • 2004
  • The climatological characteristics of coastal zone over the southwestern coast of Korea peninsula were investigated using the data observed by AWS (automatic weather system) and 4 buoy points. Coastal zone is climatologically defined as the region bounded by the distinct contrast of temperature gradient and wind speed across coastline. In the southwest of peninsula four cross-lines consisted of AWS aligned with each buoy were selected as Geojedo buoy line, Geomundo buoy line, Chilbaldo buoy line and Dukjukdo buoy line. Analysis on the diurnal cycle and intra-month variation, monthly mean and maximum value, the temperature gradient with distance between buoy and each station and the accumulative frequency of wind speed were applied to find out the characteristics and the range of coast zone. The maximum ranges of coastal zone vary from offshore to Sanglim (about 34 km distance from coastline) for Geojedo buoy line, to Sunchun (about 52 km) for Geo-mundo buoy line, to Jaeundo (about 27 km) for chilbaldo buoy line and to Yongin (about 65 km) for Dukjukdo buoy line. The modification of coastal zone according to synoptic flow was investigated for the onshore, off-shore and calm cases. The ranges of coastal zone are significantly changed with the distance between 65∼90 km for the case of onshore. In addition, we tried to find out the variation of the wind and temperature and the wind ratio of wind speed at ocean to land stations along Geojedo buoy line during 12∼13 Sep. 2003 affected by typhoon (MAEMI).

A Method of Rating Curve Adjustment (수위유량곡선보정방법에 대하여)

  • 박정근
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.18 no.2
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    • pp.4116-4120
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    • 1976
  • With the use of many rivers increased nearly to the capacity, the need for information concerning daily quantities of water and the total annual or seasonal runoff has became increased. A systematic record of the flow of a river is commonly made in terms of the mean daily discharge Since. a single observation of stage is converted into discharge by means of rating curve, it is essential that the stage discharge relations shall be accurately established. All rating curves have the looping effect due chiefly to channel storage and variation in surface slope. Loop rating curves are most characteristic on streams with somewhat flatter gradients and more constricted channels. The great majority of gauge readings are taken by unskilled observers once a day without any indication of whether the stage is rising or falling. Therefore, normal rating curves shall show one discharge for one gauge height, regardless of falling or rising stage. The above reasons call for the correction of the discharge measurements taken on either side of flood waves to the theoretical steady-state condition. The correction of the discharge measurement is to consider channel storage and variation in surface slope. (1) Channel storage As the surface elevation of a river rises, water is temporarily stored in the river channel. There fore, the actual discharge at the control section can be attained by substracting the rate of change of storage from the measured discharge. (2) Variation in surface slope From the Manning equation, the steady state discharge Q in a channel of given roughness and cross-section, is given as {{{{Q PROPTO SQRT { 1} }}}} When the slope is not equal, the actual discharge will be {{{{ { Q}_{r CDOT f } PROPTO SQRT { 1 +- TRIANGLE I} CDOT TRIANGLE I }}}} may be expressed in the form of {{{{ TRIANGLE I= { dh/dt} over {c } }}}} and the celerity is approximately equal to 1.3 times the mean watrr velocity. Therefore, The steady-state discharge can be estimated from the following equation. {{{{Q= { { Q}_{r CDOT f } } over { SQRT { (1 +- { A CDOT dh/dt} over {1.3 { Q}_{r CDOT f }I } )} } }}}} If a sufficient number of observations are available, an alternative procedure can be applied. A rating curve may be drawn as a median line through the uncorrected values. The values of {{{{ { 1} over {cI } }}}} can be yielded from the measured quantities of Qr$.$f and dh/dt by use of Eq. (7) and (8). From the 1/cI v. stage relationship, new vlues of 1/cI are obtained and inserted in Eq. (7) and (8) to yield the steady-state discharge Q. The new values of Q are then plotted against stage as the corrected steadystate curve.

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Potential repository domain for A-KRS at KURT facility site (KURT 부지 조건에서 A-KRS 입지 영역 도출)

  • Kim, Kyung-Su;Park, Kyung-Woo;Kim, Geon-Young;Choi, Heui-Joo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.10 no.3
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    • pp.151-159
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    • 2012
  • The potential repository domains for A-KRS (Advanced Korean Reference Disposal System for High Level Wastes) in geological characteristics of KURT (KAERI Underground Research Tunnel) facility site were proposed to develop a repository system design and to perform the safety assessment. The host rock of KURT facility site is one of major Mesozoic plutonic rocks in Korean peninsula, two-mica granite, which was influenced by hydrothermal alteration. The topographical features control the flow lines of surface and groundwater toward south-easterly and all waters discharge to Geum River. Fracture zones distributed in study site are classified into order 2 magnitude and their dominant orientations are N-S and E-W strike. From the geological features and fracture zones, the potential repository domains for A-KRS were determined spatially based on the following conditions: (1) fracture zone must not cross the repository; and (2) the repository must stay away from the fracture zones greater than 50 m. The western region of the fracture zones in the N-S direction with a depth below 200 m from the surface was sufficient for A-KRS repository. Because most of the fracture zones in N-S direction were inclined toward the east, we expected to find a homogeneous rock mass in the western region rather than in the eastern region. The lower left domain of potential domains has more suitable geological and hydrogeological conditions for A-KRS repository.

Determination of Terazocin in Human Plasma by Liquid Chromatography and Bioequivalence Study of Teratonin® Tablets (액체크로마토그래프법에 의한 사람 혈장 중 테라조신의 정량 및 테라토닌® 정의 생물학적 동등성)

  • Cho, Eun-Sook;Kang, Sung-Ha;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.32 no.2
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    • pp.119-125
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    • 2002
  • A rapid, selective and reproducible high-performance liquid chromatographic method has been developed for the determination of terazocin in human plasma. Terazocin plus the internal standard, prazocin hydrochloride, were extracted from alkalified plasma with tert-butylmethyl ether, back-extracted into 0.05% phosphoric acid. Fifty ${\mu}l-portions$ of extract were injected onto a octadecylsilane column and eluted with a mixture of acetonitrile, water and triethylamine (30 : 70 : 0.1 v/v, adjusted to pH 5.0 with dilute phosphoric acid) at a flow rate of 1.0 ml/min. The fluorescence intensity of column eluents was monitored at excitation wavelength of 250 nm and emission wavelength of 370 nm. No interference peaks were observed. The practical limit of quantitation was 5 ng/ml for terazocin. The average intraday and interday coefficients of variation were 4.15 and 3.54%, respectively. Also intraday and interday precisions over the range $5{\sim}60\;ng/ml$ were $0.49{\sim}2.92\;and\;0.38{\sim}5.12%$, respectively. The bioequivalence of two terazosin tablets, the $Hytrine^{\circledR}$ (Il Yang Pharmaceutical Co., Ltd.) and the $Teratonin^{\circledR}$ (Sam-A Pharmaceutical Co., Ltd.), was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Sixteen healthy male volunteers $(24.6{\pm}2.0\;years\;old)$ were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 2 mg of terazosin was orally administered, blood was taken at predetermined time intervals and the concentration of terazosin in plasma was determined with a HPLC method using spectrofluorometric detector. AUC was calculated by the linear trapezoidal method. $C_{max}\;and\;T_{max}$ were compiled from the plasma drug concentration-time data. Analysis of variance (ANOVA) was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between the two preparations were 0.21 %, 5.53% and 8.82%, respectively. The powers $(1-{\beta})\;for\;AUC_t,\;C_{max}\;and\;T_{max}$ were >99%, 97.49%, and 33.26%, respectively. Minimum detectable differences $({\Delta},\;%)\;at\;{\alpha}=0.1\;and\;1-{\beta}=0.8$ and the 90% confidence intervals were all less than ${\pm}20%$ except for $T_{max}.\;AUC_t\;and\;C_{max}$ met the criteria of KDFA for bioequivalence, indicating that $Teratonin^{circledR}$ tablets are bioequivalent to $Hytrine^{circledR}$ tablets.

Service Design for Road Environment of School Zone applied with Behavioral Psychology (행동심리를 활용한 스쿨존 도로환경 서비스디자인 개발)

  • Kim, Eok;Kim, Nak-Su
    • The Journal of the Korea Contents Association
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    • v.13 no.8
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    • pp.128-140
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    • 2013
  • The cause of traffic accidents and driver behavior is affected by psychological factors, because the behavior of drivers and pedestrians, and to identify the psychological linkage analysis to explore improvements in service design approaches are becoming increasingly important. Service design is a service-oriented development methodology that make invisible and intangible elements into visible and higher-value. Accordingly, through design thinking to action for development of products and a pleasant road environment were studied for school zone by discovering underlying issues to resolve in terms of service design. First, survey of domestic road psychological and behavioral problems were derived through the analysis of the causes of traffic accidents and researched the concept of school zones by analyzing the ideas. To reduced the width of the lane manipulate the speed of the vehicle and to cross the crosswalk safely. In order to encourage the flow of vehicle traffic, new solutions are proposed by offering robot traffic lights, graphic design of crosswalk, space, and the fence and convergence public design and services.