Electrical, Thermal, and Thermoelectric Transport Properties of Se-doped Polycrystalline Re2Te5

Se Woong Lee,Okmin Park,Hyun-Sik Kim,Won-Seon Seo,Sang-il Kim 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.12

Re2Te5 is considered a potential thermoelectric material because of its intrinsically low thermalconductivity, due to its complex crystal structure. Herein, a series of Se-doped Re2Te5 (Re2Te5-xSex, x = 0, 0.2,1, and 2) samples were synthesized, and their electrical and thermal transport properties were investigated. Pure orthorhombic Re2Te5 phases were successfully synthesized without any impurities for all compositions,and the continuous decrease in the calculated lattice parameters confirmed the substitution of Se atoms atthe Te sites. A maximum power factor of 0.135 mW/mK2was achieved for the sample with x = 0.2 at 880 K,mainly due to the increase in carrier concentration and electrical conductivity. The lattice thermalconductivity significantly decreased for all doped samples, which was attributed to the point defect phononscattering caused by Se doping. The thermoelectric figure of merit, zT reached a maximum value of 0.20 at880 K for Re2Te4.8Se0.2 (x = 0.2) sample, which was approximately 22% higher than that of the pristine Re2Te5sample. The weighted mobility, quality factor, and expected zT were calculated to evaluate the optimizationof the power factor and zT.

영어 복합명사의 의미분석

윤세웅 대한언어학회 1996 언어학 Vol.4 No.-

Yun, Se-Woong. 1996. The Semantic Analysis of English Compound Nouns. Linguistics 4, 169-192. A compound word can be defined as a combination of two or more units, though scholars' definitions are a little different. This paper uses the definition of compound nouns as units with noun function comprised of two or more nouns in order. In this paper, it is shown that what the differences between compound nouns and noun phrases are, and what the characteristics of compound nouns are. I try to introduce some linguists' theories about compound nouns, to find the problems in their theories, and to solve the problems using the conceptual structures of compound nouns based on Sows's conceptual structure theory. The basis of nouns are concepts. Therefore the basis of compound nouns are the combinations of concepts. The meaning of compound nouns depends on their conceptual relation types based on their conceptual structures. (Kwangju Women's University)

고강도강을 활용한 차량 경량화 동향 리뷰

김세호,윤재웅 대구대학교 산업기술연구소 2014 産業技術硏究 Vol.25 No.1

Weight reduction of the vehicle is strongly enforced globally due to the regulation of the fuel efficiency and emission. In this review, the R&D tends are briefly explained for the application of the high strength steel to vehicle structure for the weight reduction among many techniques. The weight portion of the body in white in the foreign exhibition shows that high strength steels are widely used with the newly developed stamping techniques. This review also illustrate stamping techniques such as hot press forming, roll forming, roll forming, servo-press and drawing process with 1Gpa-steel, which are widely appled to the manufacturing process of high strength auto-parts.

가솔린 기관의 사이클 시뮬레이션에 의한 성능과 배출가스 예측에 관한 연구

金世雄 金烏工科大學校 1988 論文集 Vol.9 No.-

The prediction of performance and exhaust emissions was wade for a spark ignition engine by cycle simulation. Several models were employed which included two-zone, thermodynamic combustion, heat transfers, chemical equilibrium, chemical kinetics for No emission. Predictions were compared with experimental data which was measured for emissions, combustion pressure and engine output. The calculated values of pressure and emissions according to operating conditions showed qualitative agreement with measured data except No concentration.

치과 기공사들에게서 나타나는 호흡기 증상과 이의 관련 요인

김웅철,오세윤,김지환,김진완,이준석,이가영,이세훈,유진호,김태석 高麗大學校 倂設 保健大學 保健科學硏究所 2001 保健科學論集 Vol.27 No.1

This study was carried out to investigate subjective respiratory symptoms and their attributable factors in Korean dental laboratory technicians. A questionnaire was mailed to randomly selected 1,900 dental laboratory technicians. Among them, 1,344 dental technicians completed the questionnaires and returmned them. Validity and reliability tests on the questionnaires were carried out before the main survey. To investigate risk factors on respiratory subjective symptoms, we performed analysis on distribution of characteristics, and then investigated univariate analysis and multiple logistic regression analysis. The prevalence rate of wheezing, cough and phlegm, and dyspnea was 4.8%, 33.9%, 54.9%, respectively. Statistically significant factors inducing subjective respiratory symptoms by multiple logistic regression analysis were sex, smoking, exercise, health examination, work hours a day, investment gas, investment dust, metal fume, resin vapor, and asbestos dust. Considering the results above, it seems that most subjective respiratory symptoms are related with health habits and occupational environmental-related factors. The result, consideration in mind, suggest that health promotion programs for smoking cessation, regular health examination, and physical exercise in health habit, and improvement on casting and resin work in dental technological environment be necessary.

좌전하행지의 제1대각선지 단독협착으로 인한 심근경색증환자의 심전도변화에 대한 관찰

서세웅 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

저자는 1986년 7월부터 1996년 9월까지 순천향대학교 의과대학 부속병원에서 허혈성 심질환으로 관동맥조영술을 시술받았던 환자 1143예중 제1대 각선지 단독협착으로 인한 급성심근경색증 환자를 선별하여 이들의 심전도변화를 비교 분석한 결과 다음과 같은 성적을 얻었다. 1. 대상환자는 5예이었고 모두 남자이었다. 연령분포는 40세부터 77세까지로서 평균 56.2세이었다. 허혈성심질환의 위험인자는 5예중 4예(80%)에서 흡연이 있었다. 2. 5예 모두(100%)가 사지유도 aVL에서 병적인 Q파를 보였다. ST절의 변화는 5예중 2예(40%)에서 보였고 T파 역위는 5예중 4예(80%)에서 보였다. 3. 5예 모두에서 전흉부유도 및 사지유도 Ⅱ, Ⅲ, aVF에서는 병적인 Q파를 보이지 않았다. 4. 제1대각선지의 협착정도는 70%부터 99%까지로 다양하였다. 이상의 결과로서 제1대각선지의 단독협착으로 인한 심전도변화는 사지유도 aVL에서 병적인 Q파를 보이면서 전흉부유도 및 사지유도, Ⅱ, Ⅲ, aVF등에서는 병적인 Q파를 보이지 않는 것이 특징이라고 생각되었으나 대상환자수가 적어서 향후 계속적인 관찰이 필요하며 나아가서는 심전도변화로써 제1대각선지 단독협착을 예측하는데 있어서의 예민도, 특이도 및 예측치에 대한 연구도 계속적으로 이루어져야 할 것으로 생각되었다. The author observed the electrocardiographic(ECG) changes in patients with acute myocardial infarction due to isolated first diagnonal branch obstruction from 1143 ischemic heart disease patients who had coronary angiography in the Soonchunhyang University Hospital from July, 1986 to September, 1996. The results are as follow ; 1. There were 5 patients who had acute myocardial infarction due to isolated first diagonal branch obstruction, all were male. Their age were between 40 and 77 years. 2. All patients(100%) had abnormal Q wave in lead aVL. However, in leads Ⅱ, Ⅲ, aVF and precordial leads, there was no abnormal Q wave. 3. The stenosis in the first diagonal branch were between 70% and 99% in diameter. From the above results, it is thought that there is a correlation between patients with acute myocardial infarction due to isolated first diagonal branch obstruction and abnormal Q wave in lead aVL. However there should be further observation.

결과지식의 정확성이 운동학습 효과에 미치는 영향

이세웅,박장평 江原大學校附設 體育科學硏究所 1992 江原大學校附設體育科學硏究所論文集 Vol.- No.17

The purpose of this study was to find out if there is any effect of the precision of knowledge of results on motor learning. Total twenty-four female students of middle school were used as subjects and divided into two groups, Quantitative KR and Qualitative KR. Each group consisted of twelve subject. The task of experiment was Liner Positioning task. The knowledge of results interval was fixed as immediately and post-knowledge of results in-terval was fixed as three seconds. As the results of experiment, the conclusions were made as follows : 1) Both quantitative KR and qualitative KR significantly have an effect on results of early performance. 2) In retention test to examine the ability of motor memory which is result of motor learning, quantivtative KR group is more excellent than Qualitative KR group and the effects are consistent.

구륜 이동 로봇의 위치추정을 위한 퍼지-유전자 제어기

한철웅,김종수,류평,오금곤,박세승 조선대학교 전자정보통신연구소 2000 電子情報通信硏究所論文誌 Vol.3 No.1

지능제어 기법중 하나인 퍼지-유전자 알고리즘은 매개변수 불확실성을 갖는 시스템을 제어하기 위한 새로운 제어 기법으로 사용되어지고 있다. 유전자 알고리즘에서, 돌연변이율은 국부적 최소화에 수렴하는 것을 방지하기 위하여 크게 설정하여야만 하지만, 전역 수렴 속도가 감소하는 문제점을 가지고 있다. 이러한 문제점을 개선하기 위하여 퍼지 논리와 유전자 알고리즘을 사용하여 제어기를 설계한다. 본 논문에서는 구륜이동 로봇의 목적궤적을 추적할 수 있는 제어기 설계를 제안한다. 제안된 제어기의 유용성은 모의실험을 통하여 보인다. Genetic algorithms, one of intelligent control methods, is used as new control approach to control the system including the parameter uncertainties In the genetic algorithm, the mutation rate must be set to high to prevent the convergence to local minimum, but it has the problem that the global convergence speed is decreased To enhance this problem, we design the controller by using the fuzzy logic and the genetic algorithm In this paper, we propose the controller design to track to the desired trajectory of the wheeled-mobile robot The validity of the proposed controller is showed through the simulation.

분산 파일 시스템 시뮬레이터의 설계 및 구현

嚴世雄,盧三赫 弘益大學校 科學技術硏究所 1996 科學技術硏究論文集 Vol.7 No.2

I/O subsystems are becoming a serious bottleneck of system performance. Recently, we have seen a concentration of research dedicated to alleviating this problem. Research in such areas as caching , prefetching, parallel file systems, and RAID are some examples. However, these studies have mostly concentrated on single stand-alone systems. The expansion of these ideas to distributed systems have been limited. This paper describes the simulation framework needed to extend the studies on these areas. Details of the design and implementation of a simulator for file systems in a distributed environment are described.

의문과 대답의 의미 분석

윤세웅 조선대학교 인문과학연구소 1994 인문과학연구 Vol.16 No.-

Natural language is a system of human communication. Language is a means to exchange information. The informative use of language is intimately linked to question answering. One might argue that there really is no separable assertoric use of language, that there is no way to get even close to understanding the way in which indicatives function if they are viewed in isolation. Whenever one tries to describe how something functions, one finds oneself looking for its goal or purpose. The main purpose of assertoric use of semantics is to convery information. If an assertion succeeds in this, it answers a question. As a matter of fact, this perspective is what drove us to. the study of questions. Our original interest was what we call epistemic pragmatics, an anslysis of the role of information in language use. The analysis aimed at was a logical one, and maybe for that reason tended to focus on the assertoric use of sentences. The present paper is organized as follows. We first concentrate on answers to single constituent interogatives, interrogative with a single occurrrence of a wh-term. Next we show that the treatment of multiple interrogatives and sentential (yes/no-) interrogatives is nothing but a straightforward generalization of the simple case. The notion of exhaustiveness, which also plays a predominant role in our analysis of wh-complements, and hence in that of interrogatives, will be seen to be of central importance in the analysis of linguistic answers just as well.