• Title/Summary/Keyword: Loss of area

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A Study on the Functional Distribution of Port Hinterland Construction and Management among Governments: Focused on the Busan New Port (정부 간 항만배후단지 개발·관리 기능배분에 관한 연구: 부산항 신항 중심)

  • Kang, Yunho;Kim, Bo-Young
    • Journal of Navigation and Port Research
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    • v.42 no.3
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    • pp.227-236
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    • 2018
  • The Busan New Port and its hinterland have not operated smoothly due to the complicated laws and various related organizations. Thus, many projects involving the port are not matched with its purpose of establishment. In particular, a large-scale apartment complex, which was constructed without a negotiation among the related organizations, is disturbing the port's logistics function. Also, the construction and management of every traffic facilities are conducted by various organizations due to the functions for the facilities are dispersed among them, which has given rise to chaos and responsibility-shifting. As a result, worries about the friction among the organizations and the loss of function of the port hinterland exist. This paper analyzes the problems of inter-governmental functional distributions in the construction and management of the port hinterland of the Busan New Port based on the principles (theories) of functional distribution. In addition, this paper proposes improvements for the functional distribution. The results of the analysis indicated that the functions for housing and traffic facilities were duplicated and dispersed among organizations, resulting in an unclear division of responsibilities. Finally, the paper proposed solutions for the problems: the institutionalization of an administrative conference system among related organizations, using an integrated administration for a wide area (contracting-out, association among local governments), and establishing a special-purpose local government (association among local governments, BPA).

Development of DAP(Dose Area Product) for Radiation Evaluation of Medical and Industrial X-ray generator (의료 및 산업용 X-선 발생장치의 선량평가를 위한 면적선량계(DAP) 개발)

  • Kwak, Dong-Hoon;Lee, Sang-Heon;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.22 no.2
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    • pp.495-498
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    • 2018
  • In this paper, we propose an DAP system for dose evaluation of medical and industrial X-ray generator. Based on the DAP measurement technique using the Ion-Chamber, the proposed system can clearly measure the exposure radiation dose generated by the diagnostic X-ray apparatus. The hardware part of the DAP measures the amount of charge in the air that is captured by an X-ray. The high-speed processing algorithm part for cumulative radiation dose measurement through microcurrent measures the amount of charge captured by X-ray at a low implementation cost (power) with no input loss. The wired/wireless transmission/reception protocol part synchronized with the operation of the X-ray generator improves communication speed. The PC-based control program part for interlocking and aging measures the amount of X-ray generated in real time and enables measurement graphs and numerical value monitoring through PC GUI. As a result of evaluating the performance of the proposed system in an accredited testing laboratory, the measured values using DAP increased linearly in each energy band (30, 60, 100, 150 kV). In addition, since the standard deviation of the measured value at the point of 4 division was ${\pm}1.25%$, it was confirmed that the DAP showed uniform measurements regardless of location. It was confirmed that the normal operation was not less than ${\pm}4.2%$ of the international standard.

Eutrophication of Shellfish Farms in Deukryang and Gamagyang Bays (득량만과 가막양 패류양식장의 부영양화)

  • CHO Chang-Hwan;PARK Kyung-Yang;YANG Han-Serb;HONG Jae-Sang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.3
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    • pp.233-240
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    • 1982
  • Some environmental parameters on the shell-fish farms in Deukryang and Gamagyang Bays during summer in 1981 were determined to find an eutrophication level for the conservation of the farm. Chlorophyll-a content in the seawater in the Deukryang Bay in September was $1.0{\sim}5.0{\mu}g/l$ with an average of $2.5{\mu}g/l$ In the superficial bottom muds, contents of COD were 5-10 mg/g, ignition loss $5-9\%$, phaeophytin pigment $2{\sim}5{\mu}g/g$, and sulfide 0.1-0.3 mg/g dry mud in both bays. High contents of both organic matters and sulfide were found in the innermost area of the Deukryang Bay and in the north western part of the Gamagyang Bay. All quantities including chlorphyll-a in the water are little less than or similar to those of Hansan-Geoje Bay, one of the most productive shellfish farms in the southern coastal waters in Korea . Eutrophication on both water and bottom mud was under way like other shellfish farms but pollution indices on the bottom mud calculated from the data of CODs and phaeophytin pigments shelved 6-11, which is much lower than those of Jinhae Bay and of the Hansan-Geoje Bay. This means that the bottom muds are in an early stage of eutrophication, unlike the Jinhae and Hansan-Geoje Bays though the water, similar to the other bays, shows a middle stage of eutrophication.

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An Influence of Additional Metals over Ni/SiO2 or Ni/Al2O3 on the Formation of CFC-1113 from CFC-113 (CFC-113로부터 CFC-1113의 합성시 Ni/SiO2(또는 Al2O3) 촉매상에서 다른 금속의 첨가효과)

  • Kim, JinHo;Park, Kun-You;Ha, Baik-Hyon
    • Applied Chemistry for Engineering
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    • v.10 no.2
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    • pp.237-241
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    • 1999
  • Nickel was impregnated on the $SiO_2$ and $Al_2O_3$ supports and applied to the reduction reaction of CFC-113 ($CF_2Cl$-$CFCl_2$) with hydrogen to 3FCl ($CF_2$=CFCl, CFC-1113). The conversion was rapidly declined on the Ni/$SiO_2$(or $Al_2O_3$) and the deactivation accelerated as the increase of Ni content. However, the selectivity of 3FCl was maintained at around 80% level. The simultaneous coprecipitation of copper and lithium on Ni/$Al_2O_3$ improved both the conversion and selectivity to 3FCl, but an excessive amount of lithium reduced the conversion as well as the selectivity of 3FCl. However, in the case of Ni/$SiO_2$, the conversion was greatly reduced possibly due to a loss of silica support with high surface area by the reaction of $SiO_2$ with HF. Such a reduction in conversion also can be ascribed to the decrease in active sites, caused by the addition of alkali metal compound, LiOH.

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Characterization of Schottky Diodes and Design of Voltage Multiplier for UHF-band Passive RFID Transponder (UHF 대역 수동형 RFID 태그 쇼트키 다이오드 특성 분석 및 전압체배기 설계)

  • Lee, Jong-Wook;Tran, Nham
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.7 s.361
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    • pp.9-15
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    • 2007
  • In this paper, we present the design of Schottky diodes and voltage multiplier for UHF-band passive RFID applications. The Schottky diodes were fabricated using Titanium (Ti/Al/Ta/Al)-Silicon (n-type) junction in $0.35\;{\mu}m$ CMOS process. The Schottky diode having $4{\times}10{\times}10\;{\mu}m^{2}$ contact area showed a turn-on voltage of about 150 mV for the forward diode current of $20\;{\mu}A$. The breakdown voltage is about -9 V, which provides sufficient peak inverse voltage necessary for the voltage multiplier in the RFID tag chip. The effect of the size of Schottky diode on the turn-on voltage and the input impedance at 900 MHz was investigated using small-signal equivalent model. Also, the effect or qualify factor of the diode on the input voltage to the tag chip is examined, which indicates that high qualify factor Schottky diode is desirable to minimize loss. The fabricated voltage multiplier resulted in a output voltage of more than 1.3 V for the input RF signal of 200mV, which is suitable for long-range RFID applications.

A Case Study on Selecting Sites for Wetland Restoration - Focusing on the Research Survey of National Inland Wetlands Monitoring in 2016 - (복원대상습지 선정 사례 연구 - 2016년 전국내륙습지 모니터링 결과를 중심으로 -)

  • Lee, Jung-Hwan;Lee, Chang-Su;Kim, Mi-Jeong
    • Journal of Environmental Impact Assessment
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    • v.28 no.1
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    • pp.71-81
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    • 2019
  • This study aims to provide basic data for the decision-making process in selecting sites for wetland restoration projects. To this end, the current list of demaged wetlands was identified based on the findings from the nationwide monitoring project in 2016 targeted at wetlands in inland areas. Then, to determine the necessity of restoration for these demaged sites, the cause of demage was investigated, and their conservation value was examined from an ecological and legal perspective. The 2016 monitoring project identified a total of 20 demaged wetlands, of which one site was deemed to have high conservation value through analysis of its ecological and legal values and on-site reviews. The results of this study are expected to support policymakers' decision-making in selecting wetlands for restoration projects since it identifies priority sites among demaged wetlands that require immediate restoration efforts. It should also be pointed out that wetlands in South Korea cannot benefit from legal protection despite their high conservation value unless they have a designated status as protected areas.

Receiver Operating Characteristic Analysis for Prediction of Postpartum Metabolic Diseases in Dairy Cows in an Organic Farm in Korea

  • Kim, Dohee;Choi, Woojae;Ro, Younghye;Hong, Leegon;Kim, Seongdae;Yoon, Ilsu;Choe, Eunhui;Kim, Danil
    • Journal of Veterinary Clinics
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    • v.39 no.5
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    • pp.199-206
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    • 2022
  • Postpartum diseases should be predicted to prevent productivity loss before calving especially in organic dairy farms. This study was aimed to investigate the incidence of postpartum metabolic diseases in an organic dairy farm in Korea, to confirm the association between diseases and prepartum blood biochemical parameters, and to evaluate the accuracy of these parameters with a receiver operating characteristic (ROC) analysis for identifying vulnerable cows. Data were collected from 58 Holstein cows (16 primiparous and 42 multiparous) having calved for 2 years on an organic farm. During a transition period from 4 weeks prepartum to 4 weeks postpartum, blood biochemistry was performed through blood collection every 2 weeks with a physical examination. Thirty-one (53.4%) cows (9 primiparous and 22 multiparous) were diagnosed with at least one postpartum disease. Each incidence was 27.6% for subclinical ketosis, 22.4% for subclinical hypocalcemia, 12.1% for retained placenta, 10.3% for displaced abomasum and 5.2% for clinical ketosis. Between at least one disease and no disease, there were significant differences in the prepartum levels of parameters like body condition score (BCS), non-esterified fatty acid (NEFA), total bilirubin (T-bil), direct bilirubin (D-bil) and NEFA to total cholesterol (T-chol) ratio (p < 0.05). The ROC analysis of each of these prepartum parameters had the area under the curve (AUC) <0.7. However, the ROC analysis with logistic regression including all these parameters revealed a higher AUC (0.769), sensitivity (71.0%), and specificity (77.8%). The ROC analysis with logistic regression including the prepartum BCS, NEFA, T-bil, D-bil, and NEFA to T-chol ratio can be used to identify cows that are vulnerable to postpartum diseases with moderate accuracy.

Burning Behavior of Flooring Materials in the Cone Calorimeter and Evaluation of Toxic Smoke (콘 칼로리미터를 이용한 건축 바닥재의 연소거동과 가스유해성 평가)

  • Lee, Jang-Won;Lee, Bong-Woo;Kwon, Seong-Pil;Lee, Byoung-Ho;Kim, Hee-Soo;Kim, Hyun-Joong
    • Journal of the Korean Wood Science and Technology
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    • v.36 no.1
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    • pp.45-53
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    • 2008
  • The burning behaviors of board for flooring materials were investigated using cone calorimetry at an incident heat flux of $50kWm^{-2}$. Seven domestic flooring materials were used to observe the burning behavior of maximum heat release rate, total heat release and average heat release rate. The experimental data indicated that the medium density fiberboard (MDF) flooring had higher release rate than the other flooring materials. Also, the mass loss of MDF flooring was higher than the other floors. When measuring the smoke production from burning, PE fiberboard flooring and PVC Plastic Resin Sheet showed higher carbon monoxide and carbon dioxide yield than the others. The average smoke release of both carbon dioxide and carbon monoxide through specific extinction area was similar. Toxic smoke measurement from flooring materials were determined by the mouse stop motion, and the results indicated that MDF flooring contains more toxic material than the other flooring materials.

A Study on Delay Time Building of Underpass for Small Car (소형차 전용 지하차도 도입에 따른 지체도 분석에 관한 연구)

  • Lee, Young-Woo
    • International Journal of Highway Engineering
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    • v.13 no.3
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    • pp.131-137
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    • 2011
  • The development of underground space essentially leads to increase in construction cost and installation of a large structure also acts as a factor deteriorating fine sight of the city. Accordingly, there recently is a trend to make city center structures light and small if possible. In this study, for efficient development of underground space, we analyzed the change in the average delay time in comparison to the existing underpass and the influence thereof using a microscopic simulation software VISSIM 5.20 after controlling heavy vehicles not to use the underpass and to detour using the intersection above the underpass, and gradually increasing the ratio of heavy vehicles in accordance with v/c of the access road in order to examine efficiency of introducing an underpass exclusive to small cars at an underground road installed and being operated in a city road area, and presented installation standard for underpass exclusive to small vehicles adequate to the traffic characteristics. Considering the findings of the study, introduction of underpass exclusive to small cars judged to be beneficial in the aspects of reduction in the economic loss resulting from land purchase, environmental damage due to construction of large traffic structures and environment-friendly green traffic.

The effect of geochemical characteristics and environmental factors on the growth of cultured Arkshell Scapharca broughtonii at several shellfish-farming bays on the South coast of Korea (남해 연안 피조개 (Scapharca broughtonii) 양식장의 환경특성)

  • Choi, Yoon Seok;Jung, Choon-Goo
    • The Korean Journal of Malacology
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    • v.32 no.3
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    • pp.149-155
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    • 2016
  • To assess the effects of environmental factors on the sustainability of cultured ark shell Scapharca broughtonii production, we investigated the habitat characteristics of shellfish-farming bays (Gangjin Bay, Yeoja Bay, Keoje Bay and Deukryang Bay). We measured the physiochemical parameters (temperature, salinity, dissolved oxygen, nutrients, chemical oxygen demand and Chlorophyll a) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several shellfish-farming bays to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain sizes for Gangjin Bay, Yeoja Bay and Keoje Bay were similar, at the ratio of silt and clay in comparison with Deukryang bay of it. The C/N ratio was more than 5.9, reflecting the range arising from the mix of marine organisms and organic matter. The C/S ratio (more than 4.2) showed that the survey area had anoxic or sub-anoxic bottom conditions. The index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. We suggested that the growth of ark shell Scapharca broughtonii in the shellfish-farming bay was effected by the various environmental conditions.