• Title/Summary/Keyword: 역저류

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A Study of Food Attitudes at the Community Level (지역집단(地域集團)의 식품태도(食品態度)에 관(關)한 연구(硏究))

  • Kim, In-Sun;Tchai, Bum-Suk
    • Journal of Nutrition and Health
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    • v.9 no.1
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    • pp.76-83
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    • 1976
  • The aims of this study are, 1) to describe the attitudes of the community towards each food item and 2) to provide the information necessary for the solution of nutritional problems due to the different food intake of the community. This study is based on the Food Consumption Survey conducted by the Ministry of Health and Social Affairs in a series of National Nutrition Survey in August, 1973. The sample included 8 communities, in which 160 households were selected at random for this study. The procedures and methods used in this study to compute the acceptability index were adopted from the study of H. Toyokawa, University of Tokyo. Food attitudes of the sample communities are clear in terms of the mean acceptability index which is presented in Table 3. The following order is indicative of the relative strength of acceptability of the respective food items: 1. Seasonings (-1.20) 2. Oils and fats (-1.12) 3. Pulses(- .60) 4. Processed vegetables (- .45) 5. Seaweeds (- .32) 6. Sugars (- .19) 7. Fresh vegetables (- .15) 8. Rice (- .13) 9. Cereals and grain products (- .07) 10. Starchy roots (- .06) 11. Fresh fish and shells (.44) 12. Processed fish and shells (.56) 13. Eggs (1.06) 14. Fruits (1.26) 15. Meats and poultry (1.33) 16. Milk and milk products (2.87) There are highly significant difference in the acceptability index between food items and the mean intake of rice, cereals and grain products, pulses, starchy roots, processed vegetables, fruits, sugars, seaweeds, seasonings, meats and poultry, eggs, fresh and shells, and oils and fats between the communities at the .01 level of significance.

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A Modeling Study on the AVO and Complex Trace Analyses of the Fracture Bone Reflection (파쇄대 반사에너지의 AVO 및 복소트레이스 분석에 관한 모형연구)

  • Han Soo-Hyung;Kim Ji-Soo;Ha Hee-Sang;Min Dong-Joo
    • Geophysics and Geophysical Exploration
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    • v.2 no.1
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    • pp.33-42
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    • 1999
  • AVO and complex trace analyses mainly used to characterize natural gas reservoir were tested in this paper for a possible application to detection of major geological discontinuities such as fracture zones. The test data used in this study were calculated by utilizing a viscoelastic numerical program which was based on the generalized Maxwell body for a horizontal fracture model. In AVO analysis of a horizontal fracture zone, p-wave reflection appears to be variant depending upon the acoustic-impedence contrast and the offset distance. The fracture zone is also effectively clarified both in gradient stack and range-limited stack in which fracture zone reflection is attenuated with the increasing offset distance. In complex attribute plots (instantaneous amplitude, frequency, and phase), the top and bottom of the fracture Tone are characterized by a zone of strong amplitudes and an event of the same phase. Low frequency characteristics appear at the fracture zone and the underneath. Amplitude attenuation and waveform dispersion are dependent on Q-contrast between the fracture zone and the surrounding media. They were properly compensated by optimum inverse Q-filtering.

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Ground-Roll Suppression of the Land Seismic Data using the Singular Value Decomposition (SVD) (특이값 분해를 이용한 육상 탄성파자료의 그라운드롤 제거)

  • Sa, Jin-Hyeon;Kim, Sung-Soo;Kim, Ji-Soo
    • The Journal of Engineering Geology
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    • v.28 no.3
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    • pp.465-473
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    • 2018
  • The application of singular value decomposition (SVD) filtering is examined for attenuation of the ground-roll in land seismic data. Prior to the SVD computation to seek singular values containing the highly correlatable reflection energy, processing steps such as automatic gain control, elevation and refraction statics, NMO correction, and residual statics are performed to enhance the horizontal correlationships and continuities of reflections. Optimal parameters of SVD filtering are effectively chosen with diagnostic display of inverse NMO (INMO) corrected CSP (common shot point) gather. On the field data with dispersion of ground-roll overwhelmed, continuities of reflection events are much improved by SVD filtering than f-k filtering by eliminating the ground-roll with preserving the low-frequency reflections. This is well explained in the average amplitude spectra of the f-k and SVD filtered data. The reflectors including horizontal layer of the reservoir are much clearer on the stack section, with laminated events by SVD filtering and subsequent processing steps of spiking deconvolution and time-variant spectral whitening.

Application of Residual Statics to Land Seismic Data: traveltime decomposition vs stack-power maximization (육상 탄성파자료에 대한 나머지 정적보정의 효과: 주행시간 분해기법과 겹쌓기제곱 최대화기법)

  • Sa, Jinhyeon;Woo, Juhwan;Rhee, Chulwoo;Kim, Jisoo
    • Geophysics and Geophysical Exploration
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    • v.19 no.1
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    • pp.11-19
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    • 2016
  • Two representative residual static methods of traveltime decomposition and stack-power maximization are discussed in terms of application to land seismic data. For the model data with synthetic shot/receiver statics (time shift) applied and random noises added, continuities of reflection event are much improved by stack-power maximization method, resulting the derived time-shifts approximately equal to the synthetic statics. Optimal parameters (maximum allowable shift, correlation window, iteration number) for residual statics are effectively chosen with diagnostic displays of CSP (common shot point) stack and CRP (common receiver point) stack as well as CMP gather. In addition to removal of long-wavelength time shift by refraction statics, prior to residual statics, processing steps of f-k filter, predictive deconvolution and time variant spectral whitening are employed to attenuate noises and thereby to minimize the error during the correlation process. The reflectors including horizontal layer of reservoir are more clearly shown in the variable-density section through repicking the velocities after residual statics and inverse NMO correction.

Identifying Cost and Benefit Items of Investment Projects to Offer New Public Services By the Use of Food Waste Disposers and the Direct Input of Feces in Sewers (주방오물분쇄기 사용 및 수세분뇨의 직투입에 따른 「새로운 공공하수도 서비스」제공을 위한 투자사업의 비용과 편익 항목 식별)

  • Oh, Hyun-Taek;Park, Kyoo-Hong;Kim, Sung Tai;Lim, Byung In
    • Journal of Convergence for Information Technology
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    • v.10 no.5
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    • pp.117-125
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    • 2020
  • Our study identifies a cost and a benefit incurred in implementing an investment project to offer new public services by use of food waste disposers and direct input of feces in sewers. This is done with identifying costs of each processing division and benefits of the project by objective statistical data and engineering perspective. In summary, cost items identified are as follows: there are house laterals, removal of septic tanks, etc. for sewer pipes system. As to water quality conservation, cost incurs in storm water outfalls and divert chambers, sewage storage tanks, equipment to treat sewer overflows, and so on. With respect to sewage treatment plants(STPs), there are so many items as increase of contaminant loads in influent of STPs, and other items. There are benefit items in health improvement due to odor mitigation, increase of energy productivity, saving cost of food waste treatment and cleaning septic tanks, etc. These estimates will be used as a basic data for its economic effect.

Characteristics of Sediment Transport due to the Construction of Jetty at the Heoya-River Mouth, Ulsan (울산 회야강 하구 도류제 건설에 따른 표사이동 특성)

  • Lee, Seong-Dae;Kim, Bong-Ik
    • Journal of Wetlands Research
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    • v.16 no.4
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    • pp.477-486
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    • 2014
  • Integrated sand control including sediment discharge from hinterland rivers is necessary to maintain coastal sand resources over a long term. In this regard, the following subjects should be considered; efficient ways to transfer discharged sand from a river to the neighboring coast, measures to improve storage efficiency of the discharged sand at the river delta and/or river terrace, measures to prevent the sand resources from being discharged into the deep sea during flooding. From the 1997 to January 2004, the jetty of 156 m length was constructed the Heoya-river mouth to protect the blockade of river mouth. Several tests were carried out to investigate the characteristics of sediment transport and morphological change due to the construction of the jetty at the Heoya-river mouth. Firstly, The sand discharge from Heoya river is quantified by one-dimensional numerical analysis assuming the mixed sand of three different particle diameters. Also the numerical mode system, which predicts the sea bed changes obtained from the Bailard's energy model(1981), was combined with the wave, wave-induced currents and sediment transport models. Then, to understand the changes to the blockade of the river mouth, several aerial photographs were compared, which showed that the changes were significant.

Catchment Similarity Assessment Based on Catchment Characteristics of GIS in Geum River Catchments, Korea (금강 유역을 대상으로 한 GIS 기반의 유역의 유사성 평가)

  • Lee, Hyo Sang;Park, Ki Soon;Jung, Sung Heuk;Choi, Seuk Keun
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.3
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    • pp.37-46
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    • 2013
  • Similarity measure of catchments is essential for regionalization studies, which provide in depth analysis in hydrological response and flood estimations at ungauged catchments. However, this similarity measure is often biased to the selected catchments and is not clearly explained in hydrological sense. This study applied a type of hydrological similarity distance measure-Flood Estimation Handbook to 25 Geum River catchments, Korea. Three Catchment Characteristics, Area(A)-Annual precipitation(SAAR)-SCS Curve Number(CN), are used in Euclidian distance measures. Furthermore, six index of Flow Duration Curve are applied to clustering analysis of SPSS. The catchments' grouping of hydrological similarity measures suggests three groups (H1, H2 and H3) and the four catchments are not grouped in this study. The clustering analysis of FDC provides four Groups; F1, F2, F3 and F4. The six catchments (out of seven) of H1 are grouped in F1, while Sangyeogyo is grouped in F2. The four catchments (out of six) of H2 are also grouped in F2, while Cheongju and Guryong are grouped in F1. The catchments of H3 are categorized in F1. The authors examine the results (H1, H2 and H3) of similarity measure based on catchment physical descriptors with results (F1 and F2) of clustering based on catchment hydrological response. The results of hydrological similarity measures are supported by clustering analysis of FDC. This study shows a potential of hydrological catchment similarity measures in Korea.

Performance Enhancement Study of a Final Clarifier by the Optimum Design of Inlet and Baffle Condition (유입구 및 정류벽 최적설계에 의한 최종 침전지 성능 개선 연구)

  • Kim, Hey-Suk;Shin, Mi-Soo;Jang, Dong-Soon;Jung, Sung-Hee;Gang, Dong-Hyo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.2
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    • pp.177-183
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    • 2005
  • The effluent quality is directly affected by the separation of biological solids in a final clarifier because the majority of discharged $BOD_5$ and SS are virtually dependent on the results of biological solids in the sedimentation tank effluent. If a final clarifier is effectively designed and operated, the desired goal of clarification for wastewater can be achieved together with the cost reduction in the treatment of wastewater. To this end flow characteristics and the removal efficiency of SS are numerically investigated especially by the change of the inlet position and the installation of baffle to improve the performance of a rectangular final clarifier. The 2-D computer program developed in a rectangular coordinates has been successfully validated against experimental residence time distribution(RTD) curves obtained by tracing radio-isotope. The lowering of the inlet position weakens the density current and induces the settling of SS in the front zone of a clarifier. Thus the decreased traveling distance of the sludge increases the removal efficiency of SS in the effluent. The inlet baffle installed in the front region of clarifier prevents the short circuiting flow and induces to flow into the dense underflow, which eventually improves the effluent quality. In the case of lower inlet position, however, installation of baffle results in degradation of effluent quality. Consequently it is strongly recommended that in-depth numerical study be performed in advance for optimizing a clarifier design and retrofitting to improve effluent quality in a final clarifier.

Impact of BMP Allocation on Discharge and Avoided Costs in an Urbanized Watershed (최적관리기법 위치분배에 의한 유역단위 하천유량과 회피비용 변화에 관한 연구)

  • Kang, Sang-Jun
    • Journal of Environmental Policy
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    • v.9 no.1
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    • pp.83-107
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    • 2010
  • Urbanized environments are constructed to estimate peak flow and cost savings in response to possible BMP allocation at a watershed scale. The main goal is to explore the proper allocation of sub-watershed level BMPs for peak flow attenuation at a watershed scale. Since several individual site scale BMPs work as a form of aggregated BMPs at a sub-watershed scale, it is a question as to how to properly allocate the sub-watershed level BMPs at a watershed scale. The Hydrological Simulation Program-FORTRAN (HSPF) is set up for a hypothetically urbanized watershed. A peak flow is determined to be the primary variable of interest and targeted to characterize the spatial distribution of aggregated BMPs. Construction cost of a regional pond forms the basis of the economic valuation. The results indicate that when total size of BMPs is constant in the entire watershed, (1) it is most effective to have aggregated BMPs in some upper sub-watersheds while the BMPs in either the mainstem sub-watershed or a single sub-watershed are the least effective choices for peak flow attenuation at a watershed scale; (2) savings exist between allocation differences and reduced peak flow increases cost savings. The largest saving is found in the strategy of aggregated BMPs in some upper sub-watersheds. These findings, however, call for follow-up site specific case studies revisiting the watershed scale impacts of BMP allocation. Then, it will be argued that location and extent of decentralization are considerable policy variables for an alternative stormwater management policy at a watershed scale.

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Evolution and Changes of Coastal Topography due to Jetty Construction at Namdae River Mouth (도류제 건설 후 남대천 하구의 해안선 생성 및 변화)

  • Kim, In Ho;Lee, Seong Dae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3B
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    • pp.315-321
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    • 2008
  • Recently, in the light of environments and utilization, countermeasures to preserve beaches in coastal area are required without depending on such as jetties and breakwaters. The necessity of integrated sand management including not only coastal sediment but also sediment discharge from hinterland rivers is increased so as to establish long-term counterplan for sediment transport. In this regard, the following subjects are examined in this study; efficient ways for discharged sand to be transported from a river to the neighboring coast, the river terrace occurrence and its growth at the river delta, measures to improve storage efficiency of the discharged sand and measures to prevent the sand resources from being discharged into the deep sea during flooding. In recent, A jetty of 260 m length was constructed at Namdae River mouth in the year of 2005 as a countermeasure against the occurrence of sand-bar at river mouth and its close. In this study, a series of numerical experiments were carried out to investigate the characteristics of sediment transport and morphological change due to the construction of jetty at the entrance of Namdae River mouth. Firstly, The sand discharge from Namdae River is quantified by one-dimensional numerical analysis assuming the mixed sand of three different particle diameters. Then, in order to understand the transport behavior of the sand discharge from river and river mouth phenomena the numerical experiments were then conducted to examine the flow behaviors of river efflux and wind generated circulations in coastal area. And, after establishing the numerical model system, which predicts the sea bed changes obtained from the flux model combining with the wave propagation, wave-induced currents and sediment transport models, the sediment transport in the vicinity of Namdae River mouth is analyzed.