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Freight Transport Demand and Economic Benefit Analysis for Automated Freight Transport System: Focused on GILC in Busan (인터모달 자동화물운송시스템 도입을 위한 화물운송수요 및 사업편익분석 - 부산 국제산업물류도시를 중심으로-)

  • SHIN, Seungjin;ROH, Hong-Seung;HUR, Sung Ho;KIM, Donghyun
    • Journal of Korea Port Economic Association
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    • v.33 no.3
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    • pp.17-34
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    • 2017
  • This study aims to analyze the freight transport demand and benefit for the introduction of an automated freight transport system focusing on the Global Industry and Logistics City (GILC) in Busan. In pursuit of this aim, four alternatives were calculated - using the freight volume estimating methods and included, the number of businesses, the number of employees set up, future estimated cargo volume, and switched volume from other transport modes into the GILC. Economic benefits were analyzed against social benefits and costs accordingly. The result of the freight transport demand forecast found, the cargo volume of "Alternative 2-1" to be the most advantageous, applying the number of employee unit method and proportion of employees in Gangseo-gu, Busan. In addition to the conventional analysis of direct benefit items (reduction of transport time, traffic accidents and environmental costs), this study also considered additional benefit items (congestion costs savings, and road maintenance costs in terms of opportunity cost). It also considered advanced value for money research in guidance on rail appraisal of U.K, Federal Transport Infrastructure Plan 2003 of Germany, and RailDec of the United States. The study aims to further contribute to estimating minimum cargo transport demands and assess the economic feasibility of the introduction of new intermodal automated freight transport systems in the future.

Improvement of Electrical Characteristics in Double Gate a-IGZO Thin Film Transistor

  • Lee, Hyeon-U;Jo, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.311-311
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    • 2016
  • 최근 고성능 디스플레이 개발이 요구되면서 기존 비정질 실리콘(a-Si)을 대체할 산화물 반도체에 대한 연구 관심이 급증하고 있다. 여러 종류의 산화물 반도체 중 a-IGZO (amorphous indium-gallium-zinc oxide)가 높은 전계효과 이동도, 저온 공정, 넓은 밴드갭으로 인한 투명성 등의 장점을 가지며 가장 연구가 활발하게 보고되고 있다. 기존에는 SG(단일 게이트) TFT가 주로 제작 되었지만 본 연구에서는 DG(이중 게이트) 구조를 적용하여 고성능의 a-IGZO 기반 박막 트랜지스터(TFT)를 구현하였다. SG mode에서는 하나의 게이트가 채널 전체 영역을 제어하지만, double gate mode에서는 상, 하부 두 개의 게이트가 동시에 채널 영역을 제어하기 때문에 채널층의 형성이 빠르게 이루어지고, 이는 TFT 스위칭 속도를 향상시킨다. 또한, 상호 모듈레이션 효과로 인해 S.S(subthreshold swing)값이 낮아질 뿐만 아니라, 상(TG), 하부 게이트(BG) 절연막의 계면 산란 현상이 줄어들기 때문에 이동도가 향상되고 누설전류 감소 및 안정성이 향상되는 효과를 얻을 수 있다. Dual gate mode로 동작을 시키면, TG(BG)에는 일정한 positive(or negative)전압을 인가하면서 BG(TG)에 전압을 가해주게 된다. 이 때, 소자의 채널층은 depletion(or enhancement) mode로 동작하여 다른 전기적인 특성에는 영향을 미치지 않으면서 문턱 전압을 쉽게 조절 할 수 있는 장점도 있다. 제작된 소자는 p-type bulk silicon 위에 thermal SiO2 산화막이 100 nm 형성된 기판을 사용하였다. 표준 RCA 클리닝을 진행한 후 BG 형성을 위해 150 nm 두께의 ITO를 증착하고, BG 절연막으로 두께의 SiO2를 300 nm 증착하였다. 이 후, 채널층 형성을 위하여 50 nm 두께의 a-IGZO를 증착하였고, 소스/드레인(S/D) 전극은 BG와 동일한 조건으로 ITO 100 nm를 증착하였다. TG 절연막은 BG 절연막과 동일한 조건에서 SiO2를 50 nm 증착하였다. TG는 S/D 증착 조건과 동일한 조건에서, 150 nm 두께로 증착 하였다. 전극 물질과, 절연막 물질은 모두 RF magnetron sputter를 이용하여 증착되었고, 또한 모든 patterning 과정은 표준 photolithography, wet etching, lift-off 공정을 통하여 이루어졌다. 후속 열처리 공정으로 퍼니스에서 질소 가스 분위기, $300^{\circ}C$ 온도에서 30 분 동안 진행하였다. 결과적으로 $9.06cm2/V{\cdot}s$, 255.7 mV/dec, $1.8{\times}106$의 전계효과 이동도, S.S, on-off ratio값을 갖는 SG와 비교하여 double gate mode에서는 $51.3cm2/V{\cdot}s$, 110.7 mV/dec, $3.2{\times}108$의 값을 나타내며 훌륭한 전기적 특성을 보였고, dual gate mode에서는 약 5.22의 coupling ratio를 나타내었다. 따라서 산화물 반도체 a-IGZO TFT의 이중게이트 구조는 우수한 전기적 특성을 나타내며 차세대 디스플레이 시장에서 훌륭한 역할을 할 것으로 기대된다.

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The History and Characteristics of Korean Traditional Ondol(Gudle) studied through Document Analysis (문헌에 의해 분석된 한국 전통 온돌(구들)의 역사와 특성)

  • Kim, June Bong;Jeong, Sang Kyu
    • KIEAE Journal
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    • v.8 no.6
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    • pp.3-10
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    • 2008
  • Since fire was founded in the world, human races have invented various heating methods. Ondol is traditional heating method in Korea. It is very the important work to trace the history and characteristics of Ondol which originated and was developed in the Korean peninsula. Especially, the study on Ondol will contribute to improving the present heating methods and predicting future ones. In this paper, we shall study through the analysis of documents such as oriental documents, the document of Choseon dynasty, European documents and American documents. In order to discover the origins of Ondol as one of the excellent heating method all over the world, This study aims at identifying the history and characteristics of Ondol in the Korean peninsula, through document analysis. Results of this study are as follows. 1) The first document about Ondol is Sookyongjoo(水經注), Chinese ancient geography book. Contents recorded in the book include the description related to Ondol at Kwankyesa temple which was located at the border land between Gogooryo(ancient Korea) and the northeast of China. 2) Ondol was popular heating method in Gogooryo(ancient Korea) and it was used in not only Gogooryo but also Silla Kingdom and Beakje Kingdom. Thereafter, it was also used widely in Goryo dynasty and Choseon dynasty. Thereby we know that Ondol has been used as a heating method for a long time in the Korean peninsula. 3) Ondol was covered with a floor paper since the beginning of Choseon dynasty. the paper made room clean and impacted on Korean life style. Because the floor was clean and warm, Koreans thus took off shoes and sat on the floor. 4) Ondol was spreaded to Jeju island in Korea before 16th century but wasn't used widely there. The reason was that Ondol was rare high class heating system and the weather was warm in Jeju island. 5) The overspreading of Ondol caused that poor people built roughly Ondol in the last of Choseon dynasty. So, the quality of Ondol gradually became lower and lower. 6) A westerner was impressed by the novelty of Ondol and Frank Lloyd Wright had played an important role to update and spread Ondol widely all over the world. Hailing Ondol as the ideal heating system, Frank Lloyd Wright began incorporating it in his buildings back in the U.S. and even invented a modified ondol system, using hot water running through pipes instead of the hot exhaust through flues.

Development of Analytical Reference Material for Proficiency Test of Pesticide Multi-residue Analysis in Tomato (토마토 농약다성분분석 정도관리용 분석표준물질 개발)

  • Kim, Jong-Hwan;Oh, Young-Gon;Choi, Sung-Gil;Hong, Su-Myeong;Kim, Sun-bae;Woo, In-Duk;Kim, Jun-Young;Seo, Jong-Su
    • Korean Journal of Environmental Agriculture
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    • v.35 no.3
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    • pp.223-233
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    • 2016
  • BACKGROUND: This study was to develop a analytical reference material including twenty pesticides in tomato. To use it for proficiency test, the suitability of homogeneity, storage stability, assigned values and uncertainty for analytical reference material were important.METHODS AND RESULTS: In order to develop a analytical reference material of tomato for multi-residue analysis of pesticides, twenty-pesticides were treated in tomato and the samples were frozen and homogenized. The homogeneity, stability, assigned value and uncertainty were calculated according to the requirements of the KS A ISO Guide 35, KS Q ISO 13528 and EURL-PT protocol. The values of the within-bottle standard variation(swb) and the between-bottle standard variation(sbb) were 0.9~6.5% of assigned value and the uncertainty(u*bb) due to inhomogeneity was also calculated as 0.6~1.9% for all pesticides. This indicated that it was satisfactory to be used as a analytical reference material. The storage stabilities of twenty-pesticides at room temperature and freezing conditions were assessed according to the requirement of the KS Q ISO Guide 35. All pesticides were stable at room temperature (20~30℃) for 8 days and freezing (-20℃) for 23 days.CONCLUSION: The feasibility of analytical reference material for pesticide multi-residue analysis in a tomato matrix was investigated. Homogeneity of within/between-bottle, uncertainty and stabilities at room temperature and freezing condition were satisfactory for a use of proficiency test and quality control. From these results, a analytical reference material would be applicable to monitor the proficiency test of pesticide analysis organizations to improve the reliability and consistency.

A taxanomic study on section Acutae of Carex L. in Korea (Cyperaceae) (한국산 사초속 왕비늘사초절의 분류학적 연구)

  • Oh, Yong Cha;Lee, Hyun Jin
    • Korean Journal of Plant Taxonomy
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    • v.31 no.3
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    • pp.183-222
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    • 2001
  • Morphological characters of section Acutae of the genus Carex (Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope (SEM) and a light microscope (LM). Morphological characters such as length and width of stem. leaf, bract, spike, scale, perigynium and achene, and shape of cross-sectioned stem, spike, scale, apex of scale, perigynium, beak of perigynium and achene, and epidermal pattern of perigynium, achene and leaf (shape of fundamental epidermal cell and cell wall, type of silica body, shape of beak epidermal cell and cell wall in perigynium, subsidiary cell shape. size and frequency of stomatal complex of leaf were useful for the identification of the observed 11 taxa. C. cinerascens, C. heterolepis and C. forficula have been confused due to similar morphological characters. C. cinerascens, C. heterolepis and C. forficula were distinct. however with respect to from width of leaf, shpae of scale, apex of scale, perigynium, beak of perigynium, and epidermal patterns of achene and leaf.

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A National Survey on Utilization of Pattern Identification among Korean Medicine Doctors (전국 한방의료기관 한의사 대상 한의 변증활용 현황 조사)

  • Yeo, Minkyung;Park, Kihyun;Jang, Eunsu;Lee, Youngseop
    • Journal of Society of Preventive Korean Medicine
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    • v.19 no.3
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    • pp.45-55
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    • 2015
  • Objective : The aim of this study was to survey the present utilization of pattern identification(PI) in the clinical field among Korean Medicine Doctors. Method : This survey was conducted from Oct. 1 to Oct. 31, 2014 by face-to-face interview using structured questionnaire. The subjects were 400 korean medicine doctors who worked in hospitals or clinics. The questionnaire consisted of two sections - a demographics section(i.e., sex, age, clinical experience, place of work, residence and so on) and the main research section(i.e., the PI utilization rate, the utilization of PI systems, the utilization of PI in the clinical domain and in the treatment domain, the correlation between utilization PI and so on). Results : This study revealed that subjects used the PI to 66.7% of their patients on average. The utilization rate of PI in patients was significantly higher for female physicians than for male physicians, for physicians worked in clinics than for physicians who worked in hospitals and for physicians with more than 10 years clinical experience than for physicians with less than 10 years clinical experience. In the utilization of PI systems, Visceral PI was most as 92.0%. There were significant difference on the PI utilization rate according to utilization of Meridian and Collateral PI, Triple Energizer PI, Defense, Qi, Nutrient and Blood PI, Six-Meridian PI and Six Excesses PI. As a result of analysing the PI utilization rate by clinical domain and in the treatment domain, the Treatment and the Drug Treatment showed the highest values. Among utilized PI systems, the correlation coefficients between Defense, Qi, Nutrient and Blood PI and Triple Energizer PI showed the highest value, but the correlation coefficients between Sasang Constitutional Medicine with the each PI showed substantially lower value. Conclusion : The results of this study demonstrate that usage of PI was higher than usage of U code(in KCD) usage in clinical field. we suggested that additional studies on using PI and developing more appropriate standardized tool should be conducted to widen scope of PI's utilization.

A Variational Inequality Model of Traffic Assignment By Considering Directional Delays Without Network Expansion (네트웍의 확장없이 방향별 지체를 고려하는 통행배정모형의 개발)

  • SHIN, Seongil;CHOI, Keechoo;KIM, Jeong Hyun
    • Journal of Korean Society of Transportation
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    • v.20 no.1
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    • pp.77-90
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    • 2002
  • Network expansion has been an inevitable method for most traffic equilibrium assignments to consider intersection movements such as intersection delays. The drawback of network expansion is that because it dramatically increases network sizes to emulate possible directional movements as corresponding links, not only is complexities for building network amplified, but computational performance is shrunk. This paper Proposes a new variational inequality formulation for a user-optimal traffic equilibrium assignment model to explicitly consider directional delays without building expanded network structures. In the formulation, directional delay functions are directly embedded into the objective function, thus any modification of networks is not required. By applying a vine-based shortest Path algorithm into the diagonalization algorithm to solve the problem, it is additionally demonstrated that various loop-related movements such as U-Turn, P-Turn, etc., which are frequently witnessed near urban intersections, can also be imitated by blocking some turning movements of intersections. The proposed formulation expects to augment computational performance through reduction of network-building complexities.

Microarray-Based Gene Expression Profiling to Elucidate the Effectiveness of Woowhangchongshim-won on ICH Model in Rats (Microarray 분석법 활용을 통한 뇌출혈 흰쥐에서의 우황청심원 효능 평가)

  • Kim, Hyung-Woo;Cho, Su-Jin;Kim, Bu-Yeo;Jeong, Byeong-Han;Bong, Sung-Jeon;Kim, Yong-Seong;Lee, Jang-Sik;Kwon, Jeong-Nam;Kim, Young-Kyun;Cho, Su-In
    • The Korea Journal of Herbology
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    • v.22 no.4
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    • pp.253-260
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    • 2007
  • Objectives : Intracerebral hemorrhage (ICH) is characterized by breakdown of blood vessels within the brain parenchyma. Fundamental therapeutic strategies for ICH, particularly those aimed at neuroprotection, have to be established. So in this experiment, the effects of Woowhangchongshim-won, a traditional prescription formula for treating Cerebral Apoplexy in Asian countries, were investigated. Methods : After intraperitoneal injection of chloralhydrate, rats were placed in a stereotaxic frame. ICH was induced by injection of 1 U collagenase type IV and drug was administered orally for 10 days. The molecular profile of cerebral hemorrhage in rat brain tissue was measured using micro array technique to identify up- or down- regulated genes in brain tissue. These genes induced by brain damage were mainly concerned with general metabolic process such as primary metabolic process, cellular metabolic process, macromolecule metabolic process, and biosynthetic process. Results : The number of genes increased in control and not-changed in experiment was 374, and decreased in control and not-changed in experiment was 527. We are concerned with genes that can be recovered by treatment with medicine, it is especially interesting to above types of genes. Conclusions : Upon medicine treatment to the rat having cerebral hemorrhage, expressions of some genes were restored to normal level. Further analysis using protein interaction database identified some key molecules that can be used for elucidation of therapeutical mechanism of medicine in future.

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A Study on the Development of KPI for Measuring Performance of B2B e-Commerce Guarantee Intermediary Service based on RFID (RFID기반 B2B 전자상거래 보증 중계 서비스의 성과관리를 위한 KPI 개발에 관한 연구)

  • Han, Chang-Hee;Kim, Min-Kwan;Kim, Jung-Min;Shin, Yun-Ho
    • Information Systems Review
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    • v.11 no.3
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    • pp.63-82
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    • 2009
  • In B2B e-Commerce(Business to Business Electronic Commerce) market, many companies use B2B e-Commerce Guarantee Service. Guarantee service raised the stability of collect debts for seller, and made purchase fund for buyer. The purpose of this study is development of KPI (Key Performance Index) for measuring performance and improving service quality. Through analysis for 'B2B e-Commerce Guarantee Intermediary Service based on RFID', the study developed KPI and made the case. The study suggests KPI of B2B e-Commerce Guarantee Intermediary Service based on RFID by IT BSC(Balanced Scorecard) model. The process of developing KPI is 4 phase. First phase is connection between service goal and KPI, second phase is make a KPI pool, third phase is development of standard for valuating and selecting index, the last phase is defining and applying of index. This study suggests the standard of measuring performance in B2B e-commerce Guarantee Service and guidelines on revitalization of service in B2B e-commerce industry and the other industry.

Policy Suggestions to Korea from a Comparison Study of the United States, the United Kingdom, Germany, the Netherlands, and Denmark's Polices on Risk Assessment of Contaminated Soils (토양오염 지역의 위해성 평가에 관한 외국 정책의 비교분석 및 우리나라의 정책 개선에 관한 고찰)

  • Park Yong-Ha;Yang Jay-E.;Ok Yong-Sik
    • Journal of Soil and Groundwater Environment
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    • v.10 no.5
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    • pp.1-10
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    • 2005
  • Policies of the United States, the United Kingdom, the Netherlands, Germany and Denmark were compared and analyzed on risk assessment of contaminated sites. These countries were chosen from a feasible preliminary analysis of 18 countries of the European Union and the U. S. All the countries selected met two major criteria : I) implementation of risk assessment to determine the soil contamination and remediation targets of contaminated sites, ii) use of soil guidance values and risk assessment as complementary measures to determine soil contamination. Suggested policy improvements to Korea regarding these issues include i) legislation of a rational risk assessment methodology of contaminated sites, and ii) enactment of collaboration of risk assessment with the soil guidance values. To establish effective risk assessment legislation, additional in-depth research on social, economic and long-term effects of the proposed risk assessment methodologies, as well as the mutual consent of all parties including academia, industry, and administration will be necessary. Linking risk assessment with soil guidance values would be applicable to a site contaminated where the contaminant concentration exceeds a certain soil guidance value. In parallel, application of risk assessment to a site where a contaminant concentration is naturally different such as mining sites would be plausible. The policy suggestions above are not yet conclusive due to a lack of policy implementation, and simulation. Thus, additional research on developing risk assessment methodology is needed. Nevertheless, initiation of the suggested policy would increase the efficacy of Korean policy regarding the survey and remediation of contaminated sites.