• JSTS:Journal of Semiconductor Technology and Science
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• 제11권2호
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• pp.80-87
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• 2011

Low temperature hole transport characteristics of gate-all-around p-channel metal oxide semiconductor (PMOS) type silicon nanowire field-effect-transistors with the radius of 5 nm and lengths of 44-46 nm are presented. They show coexisting two single hole states randomly switching between each other. Analysis of Coulomb diamonds of these two switching states reveals a variety of electrostatic effects which is originated by the potential of a single hole captured in the trap near the nanowire.

• Gut and Liver
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• 제12권6호
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• pp.633-640
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• 2018

Background/Aims: Obesity is a risk factor for gastroesophageal reflux disease (GERD), with several studies demonstrating positive associations between body mass index (BMI) and GERD symptoms. However, little is known about the effect of BMI changes on erosive esophagitis (EE). In this study, we investigated whether BMI reduction could resolve EE. Methods: A retrospective cohort study was performed to assess the natural course of EE according to changes in BMI. Participants undergoing health check-ups from 2006 to 2012 were enrolled, and 1,126 subjects with EE were included. The degree of esophagitis was measured by upper endoscopy and serially checked over a 5-year follow-up. Logistic regression and Cox proportional hazards models were used to investigate the association between BMI reduction and EE resolution. Results: Substantial weight loss is associated with EE resolution. The adjusted odds ratio for EE resolution was 1.44 (95% confidence interval [CI], 1.09 to 1.92) among participants with a decrease in BMI compared to those with no decrease in BMI. The EE resolution rate was related to the degree of BMI reduction. The effect of weight loss on EE resolution was higher among subjects who lost more weight. Compared with subjects with no decrease in BMI, the hazard ratios for EE resolution were 1.09 (95% CI, 0.89 to 1.35), 1.31 (95% CI, 1.01 to 1.72) and 2.12 (95% CI, 1.44 to 3.12) in subjects with BMI reductions of ${\leq}1$, 1-2, and >$2kg/m^2$, respectively. Conclusions: EE resolution is associated with a decrease in BMI, and weight loss is potentially an effective GERD treatment.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.40-47
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• 2014

In this paper, $Al_2O_3$ film deposited by thermal atomic layer deposition (ALD) with diluted $NH_4OH$ instead of $H_2O$ was suggested for passivation layer and anti-reflection (AR) coating of the p-type crystalline Si (c-Si) solar cell application. It was confirmed that the deposition rate and refractive index of $Al_2O_3$ film was proportional to the $NH_4OH$ concentration. $Al_2O_3$ film deposited with 5 % $NH_4OH$ has the greatest negative fixed oxide charge density ($Q_f$), which can be explained by aluminum vacancies ($V_{Al}$) or oxygen interstitials ($O_i$) under O-rich condition. $Al_2O_3$ film deposited with $NH_4OH$ 5 % condition also shows lower interface trap density ($D_{it}$) distribution than those of other conditions. At $NH_4OH$ 5 % condition, moreover, $Al_2O_3$ film shows the highest excess carrier lifetime (${\tau}_{PCD}$) and the lowest surface recombination velocity ($S_{eff}$), which are linked with its passivation properties. The proposed $Al_2O_3$ film deposited with diluted $NH_4OH$ is very promising for passivation layer and AR coating of the p-type c-Si solar cell.

• 논리연구
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• 제6권2호
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• pp.69-81
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• 2003

이 논문에서 우리는 (축약 원리가 없는) 연관 체계 EW은 이웃 체계들을 다룬다. 구체적으로 우리는 확장 원리를 포함하지만 축약 원리를 포함하지 않는 E (Ee-W) 체계, 특수 주장 specialized assertion(sa) 원리를 포함하지 않는 Ee-W (Ee-Wsa) 체계, 자기 배분 self-distribution(sd) 원리를 포함하지 않는 Ee-W (Ee-Wsd) 체계, 그리고 체인chain(c) 원리와 축약 원리를 포함하는 Ee 체계들의 확장 Eec-Wsa, Eec-Wsd, Eec-W, Eec를 다룬다. 우리는 루트리 마이어 의미론을 사용해서 이 체계들을 위한 완전성을 보인다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권6호
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• pp.581-588
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• 2013

This paper presents a study of the process temperature dependence of $Al_2O_3$ film grown by thermal atomic layer deposition (ALD) as a passivation layer in the crystalline Si (c-Si) solar cells. The deposition rate of $Al_2O_3$ film maintained almost the same until $250^{\circ}C$, but decreased from $300^{\circ}C$. $Al_2O_3$ film deposited at $250^{\circ}C$ was found to have the highest negative fixed oxide charge density ($Q_f$) due to its O-rich condition and low hydroxyl group (-OH) density. After post-metallization annealing (PMA), $Al_2O_3$ film deposited at $250^{\circ}C$ had the lowest slow and fast interface trap density. Actually, $Al_2O_3$ film deposited at $250^{\circ}C$ showed the best passivation effects, that is, the highest excess carrier lifetime (${\tau}_{PCD}$) and lowest surface recombination velocity ($S_{eff}$) than other conditions. Therefore, $Al_2O_3$ film deposited at $250^{\circ}C$ exhibited excellent chemical and field-effect passivation properties for p-type c-Si solar cells.

• JSTS:Journal of Semiconductor Technology and Science
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• 제11권2호
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• pp.73-79
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• 2011

This paper describes a reset-free delay-locked loop (DLL) for a memory controller application, with the aid of a hysteresis coarse lock detector. The coarse lock loop in the proposed DLL adjusts the delay between input and output clock within the pull-in range of the main loop phase detector. In addition, it monitors the main loop's lock status by dividing the input clock and counting its multiphase edges. Moreover, by using hysteresis, it controls the coarse lock range, thus reduces jitter. The proposed DLL neither suffers from harmonic lock and stuck problems nor needs an external reset or start-up signal. In a 0.13-${\mu}m$ CMOS process, post-layout simulation demonstrates that, even with a switching supply noise, the peak-to-peak jitter is less than 30 ps over the operating range of 500-1200 MHz. It occupies 0.04 $mm^2$ and dissipates 16.6 mW at 1.2 GHz.

• 한국환경교육학회지:환경교육
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• 제15권1호
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• pp.115-124
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• 2002

The purpose of this research is to analyze the contents related to environmental education(EE) in the elementary school textbooks for the following areas: well-balanced EE, and development of EE curriculum/teachers' guide in elementary school level. For the purpose of this analysis, elementary school teachers, education administrators and EE specialists were involved. Eleven content areas of EE, namely: natural environment, artificial environment, population, industrialization, natural resources, pollution, environmental conservation, environment sanitation, environment ethics, environmentally sound and sustainable development(ESSD), and daily li(e as a consumer, were analyzed. The results of the analysis are as follows: 1. There are total 1,140 contents related to EE in the elementary school textbooks of 7th Korea National Curriculum. 2. The textbooks of grade 6 contain the most number of EE contents, while the least number is in the textbooks of grade 3. 3. The subject that includes EE contents equally in its textbooks is social studies, and the subjects that relate a lot to EE are Korean language, science, and social studies respectively. 4. The content areas that are included a lot in textbooks are' natural environment', 'pollution', and' environmental conservation' respectively, while the contents of 'population','industrialization', 'ESSD' are included to a lesser degree. The content area most frequently mentioned in the textbooks is 'pollution', and the number of the contents are increasing along with the grade level. 5. Generally, the content areas of 'population', 'industrialization', and 'natural resources' are reflected in the textbooks to a lesser degree than others. 'Industrialization' is not included in the textbooks of grade 2, while 'population' is not included in ones of grade 4. According to the result, more concern about balanced EE in content areas is needed at the elementary school level. Similar studies tot K and secondary school levels are needed. The developmental study of EE guide book and teacher training for teaching EE using the book are also recommended.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.53-60
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• 2014

Different kinds of post-deposition annealing (PDA) by a rapid thermal process (RTP) are used to enhance the field-effect passivation of $Al_2O_3$ film in crystal Si solar cells. To characterize the effects of PDA on $Al_2O_3$ and the interface, metal-insulator semiconductor (MIS) devices were fabricated. The effects of PDA were characterized as functions of RTP temperature from $400{\sim}700^{\circ}C$ and RTP time from 30~120 s. A high temperature PDA can retard the passivation of thin $Al_2O_3$ film in c-Si solar cells. PDA by RTP at $400^{\circ}C$ results in better passivation than a PDA at $400^{\circ}C$ in forming gas ($H_2$ 4% in $N_2$) for 30 minutes. A high thermal budget causes blistering on $Al_2O_3$ film, which degrades its thermal stability and effective lifetime. It is related to the film structure, deposition temperature, thickness of the film, and annealing temperature. RTP shows the possibility of being applied to the PDA of $Al_2O_3$ film. Optimal PDA conditions should be studied for specific $Al_2O_3$ films, considering blistering.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2002년도 춘계학술발표논문집 (상)
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• pp.453-456
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• 2002

J2EE(Java 2 Enterprise Environment) 프레임워크는 확장성 있는 다단계(multi-tie.) 분산 어플리케이션을 만들기 위한 컴포넌트 소프트웨어 개발의 주요 기술로 자리를 잡고 있다. 따라서 컴포넌트 기반의 소프트웨어 개발 도구에서도 EJB 를 포함한 J2EE 프레임워크 개발을 필수적으로 지원하여야 한다. 본 논문에서는 J2EE 프레임워크 개발 및 적용에 있어서 모델링이나 개발 못지 않게 중요한 단계인 컴포넌트에 대한 표준 디스크립터 작성 및 어플리케이션 서버 탑재에 대한 확장성 있고 자동화된 방법을 제안한다.

• 한국환경교육학회지:환경교육
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• 제13권2호
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• pp.51-62
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• 2000

This study examined the current status of school environmental education (EE) in Germany, and attempted to propose strategies to develop school EE in Korea. The study intended to accomplish the following goals: First, this study attempted to examine the developmental process of school EE in Germany. Second, exemplary cases of site-based experiential education in Germany are selected and analysed to develop pedagogical strategies in school EE in Korea. The strategies for development proposed in this study can be summarized as follows: First, the focus of EE should go beyond that of "solving or curing"environmental problems and pollutions, and need to be re-directed to pursue an "education for sustainable development", a new paradigm for future EE. Second, EE should increasingly integrate outdoor site-based, experiential programs into the currently classroom-based and knowledge-driven forms of education, not only to maximize its educational effect but also and knowledge-driven forms of education, not only to maximize its educational effect but also to coordinate the instruction of EE in the context of the educational reform agenda, currently undergoing since the late 1990s, in Korea. Third, teaching-learning materials for EE should be variously developed, and programs should be encouraged to serve local needs and circumstances for effective classroom practices, and criteria for standardization and professionalization should be sought in developing these programs. Fourth, it is recommended that the Ministry of Environment secure funds to facilitate the local school authorities at the municipal and provincial levels to operate a mobile environmental support system, equivalent to the function of the "Lumbricus"in Germany. Fifth, an external support network should be established among the support agencies for EE. Especially, a professional agency or institute to academically support school EE and a special planning committee for enhancing EE need to be established for resource and personal development. Parents′voluntary participation should also be encouraged to establish a tripartite network of "school-community-government" to support and facilitate school EE.