• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.3
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• pp.134-140
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• 2002

Deep submicron NMOSFETs with elevated source/drain can be fabricated using self-aligned selective epitaxial growth(SEG) of silicon for enhanced device characteristics with shallow junction compared to conventional MOSFETs. Shallow junctions, especially with the heartily-doped S/D residing in the elevated layer, give hotter immunity to Yt roll off, drain-induced-barrier-lowering (DIBL), subthreshold swing (SS), punch-through, and hot carrier effects. In this paper, the characteristics of both deep submicron elevated source/drain NMOSFETs and conventional NMOSFETs were investigated by using TSUPREM-4 and MEDICI simulators, and then the results were compared. It was observed from the simulation results that deep submicron elevated S/D NMOSFETs having shallower junction depth resulted in reduced short channel effects, such as DIBL, SS, and hot carrier effects than conventional NMOSFETs. The saturation current, Idsat, of the elevated S/D NMOSFETs was higher than conventional NMOSFETs with identical device dimensions due to smaller sheet resistance in source/drain regions. However, the gate-to-drain capacitance increased in the elevated S/D MOSFETs compared with the conventional NMOSFETs because of increasing overlap area. Therefore, it is concluded that elevated S/D MOSFETs may result in better device characteristics including current drivability than conventional NMOSFETs, but there exists trade-off between device characteristics and fate-to-drain capacitance.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.133-144
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• 1998

International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. But, long-term & short-term interest rate is affected by Hanbo & Kia's bankruptcy, continuous large scale corporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge fund were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea. But if external factors from depreciation of yen and China's renminbi are instable, interest rate is expected to increase from capital's outflows. Third, if it is to decrease instability of foreign exchange rate from increase in surplus of future current account, credit rating's upwardness, stability of yen and renminbi, foreign exchange rate is expected to be stable. It is expected to have continuous stability from short-term interest rate to long-term interest rate in this empirical test.

• Architectural research
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• v.22 no.2
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• pp.63-73
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• 2020

This paper reports problems of current working environment on construction site in South Korea from a female laborers' point of view and proposes solutions to improve the environment. To investigate and analyze the problems, a questionnaire survey and a focus group interview were conducted with 341 engineers and 557 laborers. Among them female engineers and female laborers were 51 and 136 respectively. Findings are the facilities related with welfare facilities such as lavatories, shower rooms, lounges and changing room, etc. for women were not sufficient and even not installed only for women because all of the planners for the facilities were men and The Standard of Estimate does not consider gender distinction. The data on the trade and the number of female laborers were not recorded and this study confirmed the number and the proportion of female laborers according to construction progress i.e. the proportion of female laborers were 0% ~ 11% (average 6%) at 26 construction sites having 2% ~ 92 % construction progress. In order to solve these problems, gender education for the welfare facility planner is required and the current Standard of Estimate should be revised considering female laborers after collecting the site data for the number of female laborers according progress and the increase in the construction cost should be reflected in the contract amount accordingly. Conclusively temporary work planning related with welfare facilities should be established and conducted in terms of gender equality at construction sites. In addition, improving working environment on construction sites for female laborers will enhance the company's image and also helping solve the labor shortage problem by women laborers engaging in construction industry easily.

• Journal of Arbitration Studies
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• v.18 no.2
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• pp.173-199
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• 2008

A letter of credit transaction of the preexistence have been raising one's head fraud charge problem as a result of abusing the principles of independence and abstraction. Every society has certain rules and conventions which it regards as important and most of people in any society. The paper document means a document in a traditional paper form. The eUCP credit must specify the formats in which electronic records are to be presented. In these present times, the issuance of documentary credit are performed by the SWIFT(Society for Worldwide Inter bank Financial Telecommunication) system. The eUCP have been written to allow for presentation completely electronically or for a mixture of paper documents and electronic presentation. Presentation is deemed not to have been made if the Beneficiary's notice is not received. An electronic record that cannot be authenticated is deemed not to have been presented. The e-UCP is the supplement of current existing UCP but is superior to UCP under some circumstances. The document shall include an electronic record. The place for presentation of electronic records means an electronic address. The current e-UCP is not clear on this matter. We have to note followings in case of presenting the documents electronically and applying the e-UCP. There are three principles in the letter of credit transaction, that is to say, independence and abstraction, document dealing, strict compliance. IN the electronic letter of credit, these principles are called as independence and abstraction, electronic document dealing, strict compliance.

• Journal of Environmental Policy
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• v.9 no.4
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• pp.29-52
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• 2010

This paper analyzes the firm's financial characteristics, influence over the adoption of the ISO 14001 adoption in our analyses. We used the T-test, a logistic regression analysis. We chose 112 Steel Enterprises from Korea Accreditation Board. The independent variables are current ratio, debt ratio, fixed assets to net worth and fixed liabilities, gross margin on sales, total assets turnover, net sales growth rate. This study tests three hypotheses on management performance of adoption of ISO 14001. The main findings are as follows. The first hypothesis is supported in terms of debt ratio, fixed assets to net worth and fixed liabilities, net sales growth rate at the 1%, 5%, 5% significance level. The second one is supported in terms of current ratio, debt ratio, fixed assets to net worth and fixed liabilities at the 10%, 1%, 1% significance level. The third one is supported in terms of gross margin on sales, total assets turnover at the 1%, 10% significance level. These findings have important implications

• Korean Journal of Health Education and Promotion
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• v.33 no.5
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• pp.71-81
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• 2016

Objectives: Tobacco marketing encourages smoking initiation of non-smokers, especially adolescents, and it hinders quit intention of those who smoke or who attempt to quit smoking. Article 13 of the WHO Framework Convention on Tobacco Control(WHO FCTC) requests a comprehensive ban on tobacco advertising, promotion and sponsorship(TAPS). Ratified the Convention in 2005, Korea has partially implemented the provisions. However, online marketing regulations are still insufficient. Methods: Based on relevant national and international regulations, this research designed monitoring mechanism for online tobacco marketing and studied 1,404 websites to identify current situation of online sales and advertisement of tobacco in Korea. Results: This study found that online trade of tobacco products are overtly conducted, while tobacco advertising with flavoring and misleading descriptors are also prevalent. Also, online tobacco marketing facilitate adolescents' access to tobacco product and that advertising and promotion activities lead to tobacco purchase without difficulties. Conclusions: Fundamental solution to prevent online tobacco advertisement and promotion is banning online sales of tobacco and conducting a regular monitoring for compliance. Korean government should consider establishing an official surveillance system for online tobacco advertisement, followed by a comprehensive ban on TAPS to fulfill its obligation as a Party to the FCTC.

• Journal of the Korean Electrochemical Society
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• v.9 no.4
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• pp.170-177
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• 2006

Optimum design of flow channel in the separation plate of Proton Exchange Membrane Fuel Cell is very prerequisite to reduce concentration over potential at high current region and remove the water generated in cathode effectively. In this paper, fully 3 dimensional computational model which solves anode and cathode flow fields simultaneously is developed in order to compare the performance of fuel cell with parallel and interdigitated flow channels. Oxygen and water concentration and pressure drop are calculated and i-V performance characteristics are compared between flows with two flow channels. Results show that performance of fuel cell with interdigitated flow channel is hi민or than that with parallel flow channel at high current region because hydrogen and oxygen in interdigitated flow channel are transported to catalyst layer effectively due to strong convective transport through gas diffusion layer but pressure drop is larger than that in parallel flow channel. Therefore Trade-off between power gain and pressure loss should be considered in design of fuel cell with interdigitated flow channel.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.127-127
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• 2011

전하 트랩형 비휘발성 메모리는 10년 이상의 데이터 보존 능력과 빠른 쓰기/지우기 속도가 요구 된다. 그러나 두 가지 특성은 터널 산화막의 두께에 따라 서로 trade off 관계를 갖는다. 즉, 두 가지 특성을 모두 만족 시키면서 scaling down 하기는 매우 힘들다. 이것의 해결책으로 적층된 유전막을 터널 산화막으로 사용하여 쓰기/지우기 속도와 데이터 보존 특성을 만족하는 Tunnel Barrier engineered Memory (TBM)이 있다. TBM은 가운데 장벽은 높고 기판과 전극쪽의 장벽이 낮은 crested barrier type이 있으며, 이와 반대로 가운데 장벽은 낮고 기판과 전극쪽의 장벽이 높은 VARIOT barrier type이 있다. 일반적으로 유전율과 밴드갭(band gap)의 관계는 유전율이 클수록 밴드갭이 작은 특성을 갖는다. 이러한 관계로 인해 일반적으로 crested type의 터널 산화막층은 high-k/low-k/high-k의 물질로 적층되며, VARIOT type은 low-k/high-k/low-k의 물질로 적층된다. 이 형태는 밴드갭이 다른 물질을 적층했을 때 전계에 따라 터널 장벽의 변화가 민감하여 전자의 장벽 투과율이 매우 빠르게 변화하는 특징을 갖는다. 결국 전계에 민감도 향상으로 쓰기/지우기 속도가 향상되며 적층된 유전막의 물리적 두께의 증가로 인해 데이터 보존 특성 또한 향상되는 장점을 갖는다. 본 연구에서는 SiO2/Al2O3 (2/3 nm)와 SiO2/HfAlO (2/3 nm)의 이중 터널 산화막을 증착 시킨 MIS capacitor를 제작한 후 터널 산화막에 전하가 트랩되는 것을 피하기 위하여 다양한 열처리 온도에 따른 current-voltage (I-V), capacitance-voltage (C-V), constant current stress (CCS) 특성을 평가하였다. 급속열처리 공정온도는 600, 700, 800, 900 ${^{\circ}C}$에서 진행하였으며, 낮은 누설전류, 터널링 전류의 증가, 전하의 트랩현상이 최소화되는 열처리 공정의 최적화 실험을 진행하였다.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.305-319
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• 2002

International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. But, long-term ＆short-term interest rate is affected by Hanbo ＆ Kia's bankruptcy, continuous large scale coporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge md were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea. But if external factors from depreciation of yen and China's renminbi are instable, interest rate is expected to increase from capital's outflows. Third, if it is to decrease instability of foreign exchange rate from increase in surplus of future current account, credit rating's upwardness, stability of yen and renminbi, foreign exchange rate is expected to be stable. It is expected to have continuous stability from short-term interest rate to long-term interest rate in this empirical test.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.41-50
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• 2008

In this study, an improved scheme for distance-based registration (DBR) is proposed and its performance is analyzed. In the DBR, when a mobile station (MS) enters a new cell, it calculates the distance between last registered cell and current cell and registers its location if the distance reaches reference distance D. In this study, two-location DBR (TDBR) is proposed to improve the performance of the DBR. In the TDBR, an MS stores not only last registered location area (LA) but also previously registered LA, and then no registration is needed when the MS crosses two LAs stored already. However, since the TDBR may increase paging cost, trade-off is necessary between decreased registration cost and increased paging cost. In this study, the performances of two schemes are analyzed and compared using 2-dimensional random walk mobility model in hexagonal cell configuration. We show that our mathematical analysis is accurate by comparing with simulation. From the numerical results for various circumstances, it is shown that our proposed TDBR outperforms current DBR in most cases.