• Title/Summary/Keyword: run off

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Characteristics of Several Korean Native Herbaceous Plants for Cut Slope Revegetation (몇 가지 자생 초화류의 사면녹화 특성)

  • Song, Jeong-Seob;Chang, Young-Deug;Lee, Sang-Jeong;Bang, Chang-Seok;Huh, Kun-Yang;Chung, Meyong-Il;Chung, Hyun-Hwan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.1
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    • pp.10-16
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    • 2005
  • This experiment was conducted to study on application of several Korean native plants by seed spray methods for cut slope revegetation, and possibility of replacement almost imported tall fescue seeds by native herbaceous plants. So, we investigated growth and covering rate after sowing native plants seeds at the artificial slope plots in Suwon and the rock exposed cut-slopes in Wonju city. Emergence rate after seed spray at artificial slopes were higher Elsholtzia splendens and Dianthus superbus var. longicalycinus, showing the highest in E. splendens. Also, E. splendens, D. superbus var. longicalycinus, and Agrostemma coronaria were possible to use for seed spray at the rock exposed cut-slopes. The plots of mixed native plants show more seasonal scenery than that of tall fescue. Soil surface run-off by Typhoon was less in plot sown native plants than those of lawn grass, resulting fresh weight of roots was heavier. Thus, we found that the mixed seed spray of several native herbaceous plants, E. splendens, D. superbus var. longicalycinus, and Agrostemma coronaria, were well covered the slopes as tall fescue.

Distribution and Behavior of Mixed Contaminants, Explosives and Heavy Metals, at a Small Scale Military Shooting Range (국내 소규모 군사격장 복합오염물질(화약물질 및 중금속)의 분포 및 거동)

  • Park, Seokhyo;Bae, Bumhan;Kim, Minkyung;Chang, Yoonyoung
    • Journal of Korean Society on Water Environment
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    • v.24 no.5
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    • pp.523-532
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    • 2008
  • A phase II site investigation and feasibility study was conducted at a military mortar shooting range near the demilitarized zone (Kyunggi, South Korea) to assess the extent of contaminants migration to the nearby Imjin river in which a flood control dam is under construction. The results showed that silty-clay soils around target areas were co-contaminated with heavy metals (Cd, Cu, and Pb) and explosives (HMX, RDX, and TNT). The total amount of contaminant was estimated to be 497.1 kg-RDX, 20.6 kg-HMX, 1.4 kg-TNT, 35.2 kg-Cd, 4,331 kg-Cu, and 5,115 kg-Pb, respectively. Both heavy metals and explosives were almost equally distributed on each soil particle size fraction. Neither subsurface soil samples nor ground water samples showed signs of contamination above the environmental criteria. The major migration route of contaminants was soil particles in surface run-off during rain at which a mass discharge rate of 30.0 mg-RDX/hour was observed.

A study on the water receptivity of Korea coated paper by the fluid bridge method (액체 브릿지법에 의한 국산 도피지의 수리성 측정 연구)

  • Han, Sam-Hwa;Jeon, Su-Kyoung;Youn, Jong-Tae
    • Journal of the Korean Graphic Arts Communication Society
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    • v.23 no.2
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    • pp.143-159
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    • 2005
  • The printing could not expect the print effect of the specific character of a printing material. Specially, a property of the paper that we are aware of the substrate has controled printability as well as run ability. The objective of this study was to measure substrate properties by measuring the water receptivity in order to know the degree of the uniformity on surface of paper. Therefore, the water receptivity was measured by fluid bridge method. And then the physical properties of samples such as ink set-off, porosity and print mottle of domestic coated papers were measured by Tappi method. Accordingly, this study obtained the outcome of water receptivity. And then we could know that the relations between water receptivity and physical properties of the paper samples have correlations. There are many measurement equipments to find out print mottle by the measurement of the reflected density at this point in time. However, it is thought that the fluid bridge method is the most proper way to find out print mottle, though there are many other ways to figure out.

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Development of a Stream Discharge Estimation Program (자연하천 유량산정 프로그램 개발)

  • Lee Sang Jin;Hwang Man Ha;Lee Bae Sung;Ko Ick Hwan
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.1
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    • pp.27-38
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    • 2006
  • In this study, we developed a program to estimate discharge efficiently considering major hydraulic characteristic including water level, river bed, water slope and roughness coefficient in a natural river. Stream discharge was measured at Gongju gauge station located in the down stream of the Daechung Dam during normal and dry seasons from 2003 to 2004. The developed model was compared with the results from the existing rating curve at T/M gage stations, and was used for runoff analyses. Evaluating the developed river discharge estimation program, it was applied during 1983-2004 that base flow separation method and RRFS (Rainfall Runoff Forecasting System) which is based on SSARR (Streamflow Synthesis And Resevoir Regulation). The result presents the stage-discharge curve creator range at the Gong-ju is overestimated by approximately $10-20\%$, especially at the low stage. It is attributed to the hydraulic characteristics at the study. The discharge simulated by the RRFS and base flow separation, which is calibrated using the measurement at the early spring and late fall season during relatively d]v season, shows the least errors. The coefficient of roughness at Gongju station varied with the high and low water level.

The Oceanic Environmental Property in the Jindong Bay of the Red-Tide Appearance Area (적조 다발 지역인 진동만의 해양환경 특성)

  • 김동선;조규대;박청길
    • Journal of Environmental Science International
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    • v.10 no.2
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    • pp.159-166
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    • 2001
  • We studied the appearance and proliferation of red tide organisms from March, 1998, to February, 1999, in the Jindong Bay. There were two red tide events during investigation, and we found that the dominant species Ceratium furca in May and Gymnodinium sanguineum in September, 1998. At surface, temperature and salinity showed 18.3~19.7$^{\circ}C$ and 30.6~30.9 psu in May and 25.6~27.$0^{\circ}C$, 28.0~28.5 psu in September, respectively. When the red tide occurred, the water mass stable. Dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphate(DIP) in Jindong Bay showed seasonal variability. In May, the nitrogen was a limited nutrient in which the ratio of DIN versus DIP was less than 16 (Redfield ratio), while in September phosphate. During June to September, 1998, phosphate acted as a limited nutrient due to the increased river run-off from land. In May, chlorophyll-a, dissolved oxygen(DO) and chemical oxygen demand(COD) showed higher than 20$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 5.0mg/$\ell$, respectively. In September, they showed in turns 100$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 10mg/$\ell$, respectively.

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A Study on the Operating Problems in Dental Mechanical Laboratory in Korea and Their Reformation Devices (한국(韓國) 치과기공소(齒科技工所) 운영상(運營上) 문제점(問題點)과 개선방안(改善方案)에 관(關)한 조사(調査) 연구(硏究))

  • Choi, Un-Jae
    • Journal of Technologic Dentistry
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    • v.18 no.1
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    • pp.39-65
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    • 1996
  • The purpose of this to inquire of the people who run a dental mechanical laboratory having troubles to manage and to find out the reform measures on the point at issue. With having done random sampling for the chiefs of dental mechanical labs across the nation, and then marking the analysis of the data for the survey, I came to a conclusion to be as follow. 1. The operating problems in dental mechanical laboratory in Korea is that it is too near at hand that the requested days for the manufacture of dental prosthesis appliances form dental clinics(45%)(P<0.01) 2. The problem of dental mechanic manpower was due to a small salary and inferior working environment(35% each)(P<0.01) 3. Some of them discount dental mechanical charges in manufacturing dental prosthesis appliances(36.7%)(P<0.01) 4. Many of them employed unlicensed dental technicians(61.7%)(P<0.01) As a counterplan for the aforementioned, I think that the whole dental mechanics should cooperate in breaking off the customary custom to allow a discount on the dental mechanical charges and readjust the dental mechanical charge to a realistic level so as to contribute to the development of the dental mechanical community and the vetterment of the public oral hygience.

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A Study on the Environment Planning of Exhibition Space for Conservation of Collection in a Museum (박물관자료의 보존을 위한 전시공간 환경계획에 관한 연구)

  • Jung, Sung-Wook
    • Korean Institute of Interior Design Journal
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    • v.17 no.2
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    • pp.91-101
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    • 2008
  • The purpose of this study is to suggest the design guidelines of exhibition space for conservation of collection in a museum. With the purpose of this study, examined the concept and a condition of conservation which is focused on deterioration in a exhibition space, investigated the actual condition of total 42 facilities and analyzed the specific instance which is excellent by factor of environment plan. Hereupon, the results of this study are as follows. First, exhibition space should be equipped with sufficient 'Filtering Space' before the outdoor and located central territory in a museum facility. Second, exhibition space should be partition off an area into the quality of collection, and then controlled by each of them. Third, in consideration of the annual air fluctuation of our country, the database which is adaptable for setting up the standard of temperature and RH must be prepared. Fourth, it is necessary to establish a 'Reference Exhibition Room' which is formed cellular type and a 'Garnering Exhibition Center'. Fifth, for the prevention of deterioration which is generated in exhibition space, the showcase must be high air-tight. Sixth, it is necessary to reduce a inside space of high air-tight showcase. Seventh, art-sorb is suitable for control the organic matter of collection and a except of fiber optics is not suitable for lighting of showcase. Eighth, wall-type showcase should be have air-chamber which is formed like museum storage and run over 8 hours a day.

Numerical Analysis and Experiments for the Stratification of the Hot Water Storage (수축열조의 온도 계층화에 대한 수치해석 및 실험적 연구)

  • Yang, Y.S.;Baek, N.C.;Kim, H.J.;Yoo, J.I.;Lee, J.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.3
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    • pp.187-197
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    • 1993
  • In this study, the numerical analysis and experiments of the hot water storage using the thermal stratification techniques were carried out. The CPU time for a typical run of the the thermal stratification up to 900 seconds took one week for a $81{\times}31$ mesh size and 10 days for a $118{\times}31$ mesh size, respectively, for a cylindrical shape of the storage. In the initial stage, the numerical results were in favorable agreement with the experimental results, but it showed that the temperature gradients in the storage decreased gradually with time. It was also found that the increase of ${\delta}t$ decreased the convergent speed due to the intensive fluctuation of the velocity field in every iteration. The increase of numbers of grids is projected to forecast a more accurate result, but it made the computing time longer and woul slow down convergence. At the experiments of the flow visualization, it was confirmed that the thermal stratification was apparently built up due to the installation of diffuser at the lower part of the storage. Thus, the thermal performance of the storage could be improved by installing the diffusers at the inlet and outlet.

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Battery Lifetime Enhancement Technology Using Recovery Effect (회복효과를 이용한 배터리 사용시간 연장기술)

  • Jang, Yong-Ju;Lee, Seong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.6
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    • pp.33-38
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    • 2011
  • In recent years, mobile devices and high-hearth because of the multi-functional, battery usage is increasing. But compared to the required computing power increases the battery's energy capacity of the research is going slowly. In this paper we use the battery discharge characteristics, can be used in battery research and to increase the effective capacity, wireless transmission of power from the system just by turning off the technology to extend battery life is explained. Experimental transmission of images through the standard battery drain intervals according to measuring battery life, and applications used in these experiments and heuristic to optimize battery run time was achieved.

The effect of security factors on the continuance of Internet banking usage among Malaysians

  • Normalini, M.K.
    • Asia-Pacific Journal of Business
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    • v.6 no.1
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    • pp.27-43
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    • 2015
  • The objective of the present study is to identify the security factors that influence customer trust towards intention to continue using Internet banking in Malaysia. The participants are individual Internet banking users in Peninsular Malaysia. Data was collected through self-administered questionnaires distributed using the drop-off and pick-up (DOPU) technique to bank branch managers who then passed the questionnaires to their customers. A total of 413 respondents completed the questionnaires. The SPSS statistical analysis software package and Partial Least Squares statistical method were used for data analysis and hypothesis testing. The results show that authentication, confidentiality, data integrity and non-repudiation are significant factors that influence customer trust towards intention to continue using Internet banking. Trust plays a critical role in influencing the intention to continue using Internet banking in Malaysia while perceived privacy does not. An understanding of the factors identified in this study will enable Internet banking providers to effectively and efficiently enhance the security of services and thereby promote continued usage of Internet banking among customers. The findings of this study are thus expected to be of great use to Internet banking providers as improvements in Internet banking security will increase business in the long run.

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