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.

국가 대표급과 제주도 고교 대표급 수영선수들의 그랩 스타트의 운동학적 분석

김철원,김승곤,오만원,임상용,김성찬,이창준,남사웅,이세형,류재청,신석종,김세민 濟州大學敎 體育科學硏究所 1998 체육과학연구 Vol.4 No.-

The purpose of the study was to undertaken to analysis the Grab starting technique between national representive team(3) and Cheju's representive team(3) with 3D cinematography. The conclusions obtained were as follows: Cheju's showed more elapsed time than national representive team on starting block. and more vertical than horizontal direction of COG position, more concentrated vertical velocity & acceleration than forward direction. Therefore It is necessory for cheju's to train balanced trust force in horizontal and vertical direction in grab starting technique.

공급사슬에서 수량할인과 수익공유를 반영한 계약

박세호(Se Ho Park),이영해(Young Hae Lee),조동원(Dong Won Cho) 한국SCM학회 2012 한국SCM학회지 Vol.12 No.2

One of the most important reasons in pursuit of supply chain management is to prevent sub-optimization caused by decentralized decision making over the various entities. As supply chain coordination approach to overcome such a setting, contract mechanisms have frequently been used. However, a coordinated supply chain might fail to provide additional profit to one of the players. In result, it is necessary that a contract mechanism is designed to achieve the same profit in a centralized situation (coordination) and to improve the benefit of all the supply chain players (winwin). In this paper, we address supply chain contract based on revenue sharing and quantity discount considering price and service level. We show that the trade parameters among different entities in the supply chain contract can be chosen to achieve coordination and a win-win outcome.

아동보호전문기관 사회복지사의 윤리적 딜레마와 의사결정에 관한 연구

이세원(Lee Se-Won) 한국사회복지학회 2008 한국사회복지학 Vol.60 No.1

본 연구는 아동보호전문기관 사회복지사들의 윤리적 딜레마와 의사결정을 중심으로 연구를 진행하여 그들의 윤리적 고충을 이해하는 동시에 실천적이고 정책적인 제언을 하는 데에 목적이 있다. 본 연구의 수행을 위하여 질적연구방법론 중에서도 현상학적 연구방법을 사용하였고, 14명의 아동보호전문기관 사회복지사와의 인터뷰 내용을 Colaizzi(1978)의 분석단계에 따라 분석하였다. 총 8개의 주제묶음과 26개의 소주제들을 통해 아동보호전문기관 사회복지사는 ‘정책/제도의 미흡함과 업무의 과다 속에서 피학대 아동을 만나면서 직접적이고 간접적인 윤리적 딜레마에 빠짐’을 대주제로 도출하고, 총 4개의 주제묶음과 9개의 소주제들을 통해 ‘책임과 부담을 떠안은 채로 최선이라 생각하며 의사결정을 수행함’을 대주제로 도출할 수 있었다. 이에, 이와 관련된 향후 논의점들을 제시하였다. The aim of this study is to understand the ethical struggles of Child Protective Service(CPS) social workers and to indicate some implications for future studies by conducting research focusing on their ethical dilemmas and decision-making. This study used qualitative methods, in particular the phenomenological approach and 14 in-depth semi-structured interviews with CPS social workers, and were conducted and analyzed using the procedures of Colaizzi(1978). This study looks at the following research questions: 1) What kind of ethical dilemmas do CPS social workers encounter? This means what ethical dilemmas do they directly or indirectly encounter because of policy or system inadequacies and huge caseloads. 2) How do the CPS social workers make decisions when they are faced with ethical dilemmas? Making the best decisions with all of their responsibilities and burdens is the focus of this question. This study suggests the following discussions: First, efforts to emphasize 'ethics' at CPS are needed. Second, proper policies and systems based on the Korean situation are needed so that CPS social workers won’t have to face 'needless' ethical dilemmas. Third, an index of ethical problems or ethical codes is necessary because principles are important to those social workers who face ethical dilemmas. Fourth, an ethical committee that protects the CPS social workers by supporting their decisions and being responsible for them is needed. Last, a debriefing system that reduces a CPS social worker's psychological trauma caused by ethical dilemmas should be available.

바이오매스 합성가스를 이용한 엔진 발전 시스템의 경제성 평가

문지홍(Ji Hong Moon),이정우(Jeung Woo Lee),방병열(Byung Ryeul Bang),김세원(Se Won Kim),이은도(Uen Do Lee) 한국열환경공학회 2010 한국열환경공학회 학술대회지 Vol.2010 No.추계

Biomass, a carbon neutral fuel, is one of the fastest growing renewable energy sources. In this study, economic feasibility of small scale power generation system using syngas from biomass has been investigated. Effects of important variables such as capital investment, cost of waste wood, renewable energy certificate(REC), system marginal price(SMP) on the benefit of business have been analyzed. Internal rate of return(IRR) was predicted as 16.90%, which implicates the business is promising based on the assumptions such as SMP of 137 Won/kWh, capital cost of 4.7 billion won, and waste wood price of 30 thousand won. Major factors affecting the benefit of business are as follows; system marginal price, operational rate, capital investment, expenditure of waste wood, certified emission reduction.

복숭아의 生理的 落果에 관한 硏究 : 복숭아의 生理的落果와 總糖, 窒素 및 水分과의 相關

元世鎬 東國大學校 1967 論文集 Vol.3-4 No.-

The physiological drop occurs heavily on peach trees. The lack of fertilization and the discontinuation of development of embryo are the causes of the physiological drop; and the total sugar, nitrogen and water in the fruits are the factors closely related to the discontinuation of development of embryo. It is said the deficiency of total sugar, nitrogen and water in the fruits cause the physiological drop, and the deficiency of nitrogen or water supply in the soil cause the physiological drop and also the excessive supply of nitrogen or water in the soil cause the physiological drop. It is easy to understand that the physiological drop occurs when the total sugar, nitrogen and water are short in the fruits, and also when the nitrogen or water supply were deficient in the soil, but it is a little hard to understand why the physiological drop eccurs when nitrogen or water is excessively supplied in the soil. Therefore this experiment was made to check the relationship between the physiological drop and the total sugar, nitrogen and water in the fruits, and nitrogen or water in the soil. The results obtained in this experiment are summarized as follows: 1. The dropped fruits contained less total sugar than the fruits not dropped. This means the deficiency of total sugar supply on the fuits is the cause of physiological drop. 2. The deficiency of nitrogen or water supply in the soil reduced absorptioin of them in the plant body; the nitrogen or water content ini the leaves were reduced and it caused the physiological drop; and the dropped fruits contained less nitrogen or water than the fruits not dropped. This means the short supply of nitrogen or water to a fruit causes physiological drop. 3. Excessive nitrogen or water supply in the soil results in the significant absorption of nitrogen or water in the plant body, and the leaves also contained more nitrogen or water, however, physiological drop occured in this case also. The dropped fruits contained less nitrogen or water than the fruits not dropped. In this case vegetative growth of the shoots and leaves were very vigorous. Also, when the excessive supply of nitrogen or water was given to the soil, the physiological drop takes place. This phenomenon, considered in the light of the above, because too much nitrogen or water was exhausted in the vegetative growth of shoots and leaves. As a result, it is supposed that has been caused by the short supply of nitrogen or water into the fruits.

체외순환 없이 시행한 관상동맥우회술의 조기성적

원태희,최세용,양인숙 이화여자대학교 의과대학 2005 EMJ (Ewha medical journal) Vol.28 No.1

Background : The advances in surgical techniques and stabilizing devices have made the off-pump coronary artery bypass (OPCAB) popular, and good results have been published. We analyzed the early results of OPCAB performed in our hospital. Materials and Methods : Between January 2004 and December 2004, 23 patients underwent OPCAB. There were 14males and 9 females with mean age of 62.6± 10.3years. Preoperative diagnoses were unstable angina in 13(57%), acute myocardial infarction in 9(39%), and stable angina in 1(4%). Preoperative angiographic diagnoses were three-vessel disease in 12 (52%), two-vessel disease in 8(35%), one-vessel disease in 1(4%), and left main disease in 2(9%). Results : The mean number of grafts was 2.6 ±0.9 per patient. Vessels accessed were left anterior descending artery in 23, diagonal branch in 14, obtuse marginal branch in 9, right coronary artery in 12, and posterior descending artery in 1. Left internal mammary artery were used in 22 patients and bilateral internal mammary arteries were used in 1 patient. There was no operative mortality. Postoperative complications were cerebral vascular accident in 1, postoperative bleeding which required operative management in 2, arrhythmia including atrial fibrillation in 5, and minor operative wound problem in 1. Pre-discharge graft patency was evaluated in 11 patients. One internal mammary artery graft was occluded in 11 internal mammary artery graft evaluated. The patency rate was 91%. Seventeen saphenous vein grafts were patent in 19 saphenous vein grafts and the patency rate was 89%. Conclusion : Our result of OPCAB is promising and OPCAB is suggested to be the ideal technique with less morbidity and mortality.

동진강 유역 비점오염원 정밀조사

원찬희,정팔진,김민정,조선영,김세훈,김종천 전북대학교 공학연구원 ( 구 전북대학교 공업기술연구소 ) 2002 工學硏究 Vol.33 No.-

Nonpoint source pollution(NSP) arises due to agriculture activity and it is quite an extensive and complicated problem in order to control and has received a great deal of concern during the recent years, whereas point source are known to originate from an estimated volume of contaminant discharged from a distinguishable source. Extensive research work have been conducted and presented in the past with regard to the various characteristics of watershed on Dong Jin River(DJR), however there are certain drawbacks of existing survey for determining important polluting sources, distribution features of pollutants and estimated load of the organic and nutrients from the creeks. Unfortunately, investigation for loadings originating due to agricultural drainage was not satisfactory, although the regional consideration for DJR across Kim Je Field(KJF) as an agricultural area receives a reasonable source point in the agri-pollution management. Therefore it was necessary to carry out a thorough investigation into the diffuse sources resulting, to form the pollution-developing estimation and to evaluate the output roperties and determining various factors in the generation of non-point pollution. Eventually, this research work would serve as an useful tool for the development of predictive pollution management for DJR. Non-point sources in the present work were classified as municipal non-treated sewage water discharged into the river, loadings through agricultural drainages in the dry/wet field and inadequate treatment of wastewater generated from livestocks. The entire duration of the research work was from December-2001 to July-2002. Site measurement were conducted during various season, in a dry season(December), in rainfall, in seed-sowing time and also collecting data from the rural public organizations related to water management was done and examined and examined during the mid of research work. Similarly, domestic wastewater loadings due to population was based on area unit, as City, Country, Up, Myon, Dong, Ri. The Dong Jin River watershed contains small three Creeks, KoBu(KB), DongJin(DJ, including JeongEup(JE) and ChilBo(CB), WonPyong(WP). It was further divided into 32 sub-watersheds which comprises of further 5,18,9 watersheds in the creeks respectively. The results obtained from research work are presented as follows. Animal productions have marked differences in the rate of pollutant loadings reported in the following sequence: DJ(only CE)>WP>CB>KB, in a case of Korean cow and milk cow. However, it was revealed that WP creek became significantly higher than any other livestocks. According to statistical data for land use, rice field(369.0㎢) and forest(378㎢) have much occupation prior to dry paddies(125.0㎢), residential land(32.0㎢) and others(5.0㎢). Especially, rice fields receives 2.5∼3 times than dry paddies in size.

切接時 接着部의 비닐被覆이 活着 및 生育에 미치는 影響

元世鎬 東國大學校 1965 論文集 Vol.2 No.-

In order to promote the formation of healing tissues by preventing dryness of sion and contact portion of sion in veneer-grafting, the grafted plant has usually been mounted with soil only as high as the upper portion of sion or else painted by grafting wax. But, if contact portion of sion is wrapped and tied with vinyl, the grafting operation would be simpler and the cost would be less; and the following are the data of my research work regarding the above statement. 1. In the sections where the grafted portion was painted with grafting wax or wrapped and tied by vinyl, the sion and its contact portion were prevented from becoming dry; the rate of union of the sion was far better. Therefor it is found that wrapping of grafted portion by vinyl bring higher efficiency in veneer-grafting operation. It is the best method form the economical aspect. 2. No differences were recognized on the growth of grafted plants in all sections through germination, green tip and subsequent stages.

잠복원발종양의 원발병소 진단시 내시경 유도하 생검 및 구개편도적출의 진단적 의의

김세헌,김광문,이준협,이승수,서진원,홍원표 대한이비인후과학회 1998 대한이비인후과학회지 두경부외과학 Vol.41 No.3