Sodium–Metal Halide and Sodium–Air Batteries

Ha ,, Seongmin,Kim ,, Jae‐,Kwang,Choi, Aram,Kim, Youngsik,Lee, Kyu Tae WILEY‐VCH Verlag 2014 ChemPhysChem Vol.15 No.10

<P>Impressive developments have been made in the past a few years toward the establishment of Na-ion batteries as next-generation energy-storage devices and replacements for Li-ion batteries. Na-based cells have attracted increasing attention owing to low production costs due to abundant sodium resources. However, applications of Na-ion batteries are limited to large-scale energy-storage systems because of their lower energy density compared to Li-ion batteries and their potential safety problems. Recently, Na-metal cells such as Na-metal halide and Na-air batteries have been considered to be promising for use in electric vehicles owing to good safety and high energy density, although less attention is focused on Na-metal cells than on Na-ion cells. This Minireview provides an overview of the fundamentals and recent progress in the fields of Na-metal halide and Na-air batteries, with the aim of providing a better understanding of new electrochemical systems.</P>

ACCase 저해 제초제 cyhalofop-butyl에 대한 경남지방 수집종 피의 저항성

원종찬,원옥재,하준,임일빈,강광식,변종영,박기웅,이증주,Won, Jong Chan,Won, Ok Jae,Ha, Jun,Im, Il-Bin,Kang, Kwang Sik,Pyon, Jong Yeong,Park, Kee Woong,Lee, Jeung Joo 한국잡초학회한국잔디학회 2018 Weed & Turfgrass Science Vol.7 No.2

Repeated use of ACCase inhibiting herbicides for a long time has resulted in increases of resistant Echinochloa oryzicola populations in paddy fields in middle west area of Korea. This study aims to investigate current status of herbicide resistant E. oryzicola in Gyeongsangnam-do, in which there is less information about herbicide resistance. For resistance frequency and dose-response study, seeds from 100 individual plants of E. oryzicola in Gyeongsangnam-do were collected and tested with cyhalofop-butyl. Seven percent of plants from Gyeongsangnam-do was resistant at a recommended rate of cyhalofop-butyl. $GR_{50}$ values (herbicide rates required to reduce plant growth 50%) for one representative resistant populations and five susceptible populations were $738g\;a.i.\;ha^{-1}$ and 66-234 (average 147)$g\;a.i.\;ha^{-1}$, respectively, indicating average 5 times difference in resistance. Although lower rate of frequency of herbicide resistance in Gyeongsangnam-do than in Jeollabuk-do, increases of herbicide resistance are expected in this area because of increases of direct seeded rice fields and increases of dependence on a specific herbicide. Therefore, it is necessary to monitor herbicide resistance regularly and conduct integrated herbicide resistance management in this area. 경남지역 제초제 저항성 피의 발생현황과 저항성 정도를 알아보기 위하여 벼 재배 논에서 100개체의 피 종자를 수집하여 ACCase 저해제인 cyhalofop-butyl에 대한 약량반응 실험을 수행한 결과, 수집한 피의 7%가 저항성으로 조사되었다. 선발된 감수성 5개체의 $GR_{50}$값은 평균 $147g\;a.i.\;ha^{-1}$로 나타났고, 함양 지역의 저항성 개체의 $GR_{50}$값은 $738g\;a.i.\;ha^{-1}$ 로 R/S (ratio of resistance to sensitivity)값은 5.01배로 나타났다. 현재 경남지역에서의 저항성 피의 발생 수준은 낮은 것으로 나타났지만, 저항성 피의 확산을 지연시키거나 막기 위해서는 주기적인 저항성 피의 모니터링과 체계적인 저항성 잡초 관리방안을 마련하여 수행할 필요가 있다.

전산화단층사진상을 이용한 하악관의 위치 및 하악골의 피질골 두께에 관한 연구

하쌍용,고광준,송남규 大韓口腔顎顔面 放射線學會 1997 Imaging Science in Dentistry Vol.27 No.1

The location of the mandibular canal and the cortical thickness of the mandible is important in the practice of dentistry. This study was performed on twenty chosen dry mandibles, which were of adults and included fully erupted premolars and molars. The purpose of this study was to evaluate the location of the mandibular canal and the cortical thickness of the mandible on computed tomograms and to aid in the surgical treatment plans. The obtained results were as follows; 1. The horizontal distance between the mandibular canal and the buccal external border was 6.6±0.9mm on S?(mesial root of the first molar),and it was increased posteriorly. The horizontal distance between the mandibular canal and the lingual external border was 4.1±1.1mm on S?, and it was decreased posteriorly. 2. The vertical distance between the alveolar crest and the mandibular canal was 16.9±1.6mm on S?, and it was decreased posteriorly. The vertical distance between the inferior border of mandible and the mandibular canal was 8.8±1.3mm on S?, and it was increased anteriorly and posteriorly. 3. The thickness of the buccal cortical plate was 2.2±0.4mm on S?. and it was increased posteriorly. But, that of the lingual cortical plate was 2.0±0.6mm on S? and it was decreased posteriorly. 4. The area of the buccal cortical plate was 66.5±1.0mm²on S? and it was increased posteriorly. But, that of the lingual cortical plate was 65.8±0.9mm²on S? and it was decreased posteriorly.

Bridgman법에 의한 CdIn₂Te₄ 단결정 성장과 defect 연구

하종호,홍명석,홍광준 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.2

수평 전기로에서 CdIn₂Te₄ 다결정을 합성하여 Bridgeman 법으로 3단 수직 전기로에서 CdIn₂Te₄ 단결정을 성장하였다. 성장된 결정의 특성은 x선 회절과 광발광 측정으로 조사하였다. CdIn₂Te₄ 단결정 시료는 Laue에 배면 반사법에 의해서 (001)면으로 성장되었음을 확인하였다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293K에서 각각 8.61×10^(16) /㎤, 242 cm²/V·s였다. CdIn₂Te₄ 단결정의 광흡수와 광전류 spectra를 293K에서 10K까지 측정하였다. 광흡수 스펙트럼으로부터 band gap E_(g)(T)는 Varshni 공식에 따라 계산한 결과 1.4750eV-(7.69×10^(-3) eV/K)T²/(T+2147 K)임을 확인하였다. 막 성장된(as-grown) CdIn₂Te₄ 단결정 시료를 Cd-, In-, Te 분위기에서 열처리하여 10K에서 photolumine science(PL) spectra를 측정하여 점 결함의 기원을 알아보았다. CdIn₂Te₄ 단결정내에서 내재된 결함들의 기원을 10 K에서 광발광을 측정하여 연구되었다. PL 측정으로부터 얻어진 V_(Te), Cd_(int), 그리고 V_(Cd) Te_(int)는 주개와 받개로 분류되어졌다. CdIn₂Te₄ 단결정 시료를 Cd 분위기에서 열처리하면 n형으로 변환됨을 알 수 있었고, In 분위기에서 열처리하면 열처리 이전의 PL spectra를 보이고 있어서 I₂, I₁ 및 S.A emission에 의한 PL peak에는 영향을 주지 않는다고 보았다. A stoichiometric mixture for CdIn₂Te₄ single crystal was prepared from horizontal electric furnace. The CdIn₂Te₄ single crystal was grown in the three-stage vertical electric furnace by using Bridgman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. The (001) growth plane of oriented CdIn₂Te₄ single crystal was confirmed from back-reflection Laue patterns. The carrier density and mobility of CdIn₂Te₄ single crystal measured with Hall effect by van der Pauw method are 8.61×10^(16) ㎤ and 242 ㎠/V·s at 293K, respectively. The temperature dependence of the energy band gap of the CdIn₂Te₄ single crystal obtained from the absorption spectra was well described by the Varshni's relation, E_(g)(T) = 1.4750 eV - (7.69× 10^(-3) eV)T²/(T+ 2147). After the as-grown CdIn₂Te₄ single crystal was annealed in Cd-, In-, and Te-atmospheres, the origin of point defects of CdIn₂Te₄ single crystal has been investigated by the photoluminescence(PL) at 10 K. The native defects of V_(Te), Cd_(int), and V_(Cd), Te_(int) obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Cd-atmosphere converted CdIn₂Te₄ single crystal to an optical n-type. Also, we confirmed that In in CdIn₂Te₄ did not form the native defects because In in CdIn₂Te₄ single crystal existed in the form of stable bonds.

동시공학적 측면에서의 R.P.(Rapid Prototyping) 기술 적용에 관한 연구

河光哲 서원대학교 예술문화연구소 2000 예술문화논총 Vol.9 No.-

In the 1990's, with competing products in every market segment-most produced with similar technologies, similar features and materials, and almost identical pricing; design may soon be the only element that differentiates one product from another. Industrial design is not merely a function. Design provides the essential link between engineering, manufacturing, and the market place, and in essence, is the primary ingredient to present and future success. These trends, coupled with rapid development in information technology, crate a far mor important role for industrial designers. It is no longer enough for industrial designers to be artists or stylists. The new generation of industrial designers will manage information, understand business, markets, materials and processes, as well as participate as equal partners with other organizational elements on cross-functional product development teams. Being competitive as an industrial designer will require adaptability and a progressive attitude toward product development. Companies will have to reduce product development "cycle time" to quickly get a product from the drawing board to market. It will also be necessary to generate a continuous stream of new products that can target market niches for increased market penetration, share, and company image. Designers and design firms will have to be adaptive to survive. They have to embrace the time and material saving capabilities of emerging computer technologies, which can provide the benefits of concurrent product development process. Using computers to model the complicated and sophisticated shapes of today's products correctly has become a trend. However, designers and model makers are still making the physical models by hand. Model-making is essential part of product development. We simply cannot overlook the importance of the accuracy of design models and engineering prototypes because they are the only means of real evaluation before the final products are made. By incorporating the R.P. technology in our product development cycle in right manner, we can eliminate the possbible reinterpretation in the successive departments by reading the 2D drawings. We have numerous computer-aided design systems available to us today. However, the key is implementation. By carefully evaluating different systems and the needs will only guarantee the perfect match for you and your companies and provide the leading edge.

新경제5個年計劃에 대한 評價

姜光夏 서울대학교 경제연구소 2001 經濟論集 Vol.40 No.2

新경제5개년계획은 수립 · 집행과정에서 다른 5개년계획과는 차이를 보이고 있다. 즉 계획의 입안을 민간부문에서 한 것이라든가, 발전모델이 아니라 개혁프로그램이라든가, 5년 동안 지속적으로 추진되지 못했다든가 등 여러 가지 특징을 보여주었다. 또한 현시점에서 볼 때 우리 정부가 만든 마지막 5개년계획이다. 따라서 新경제5개년계획에 대한 評價는 매우 의미있는 일이라 하겠다. 新경제계획은 재정, 금융, 행정규제에 대한 제도개혁과 국민의식개혁을 주축으로 하는 改革과 성장잠재력의 강화, 국제시장기반의 확충, 국민생활여건의 개선에 대한 經濟施策 등 크게 두 가지 부분으로 나누어져 있다. 계획의 목표와 정책이 원칙적인 면에서 시의적절하고 중요하다는 점에서 긍정적인 반면, 구체적 실천방안과 지속적인 추진이라는 점에서는 부정적인 평가를 내릴 수 있다 新경제5개년계획에 대한 評價를 통해 經濟計劃의 必要性에 대한 論議에도 하나의 좋은 資料를 제공할 수 있을 것이다.

기존 철근콘크리트 프레임의 내진성능 개선을 위한 재생 시스템의 개발

하기주,김광연 경운대학교 산업기술연구소 2000 産業技術硏究論文誌 Vol.3 No.1(B)

In this study, experimental research was carried out to evalulate the hysteretic behavior of reinforced concrete frame designed by high performance techniques, using carbon fiber plate, K-type bracing system with or without steel frame. Experimental programs were accomplished to evaluate the structural performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. Specimens(RFCP, RFKB, RFKB-F), designed by the improvement of earthquake-resistant performance, were attained more load-carrying capacity and stable hysteretic behavior.

SPICE를 이용한 다이나믹 D 플립플롭의 성능 연구

하영철,양광진,임영도,홍창희 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.1

In this paper, we analyze two D flip-flop generally considered to be fastest (and most widely used), and compare their speed performance and their speed performance and their robustness against clock skew when a two-phase clocking scheme is applied. The effect of click skew on their speed and proper logic operation is analyzed and verified with SPICE simulation.

新經濟 100日 計劃

姜光夏 서울대학교 경제연구소 2000 經濟論集 Vol.39 No.3

新경제 100일 計劃을 계획 수립 및 목표 설정, 계획 집행 및 수단 설정을 중심으로 평가해 보기로 한다. 신경제 100일 계획은 신경제 5개년 계획의 성공적인 추진을 위한 준비단계로 수립한 계획으로서 경제개혁을 위한 체력보강에 주목적이 있었다. 이러한 제약 때문에 처음부터 한계가 있는 경제계획이 되었으며, 결과적으로도 상호 모순이 되는 정책방향과 정책수단이 혼재한 계획이었다. 그 결과 신경제 5개년 계획의 추진에 오해와 혼선을 가져오기도 하였다. 그러나 경기활성화와 규제완화에는 어느 정도 성공한 긍정적인 측면도 있다.

꽃게 껍질을 이용한 키토산의 제조 및 Escherichia coli의 생육 억제효과

하정욱,이광현,황용일 慶南大學校 附設 工業技術硏究所 1996 硏究論文集 Vol.14 No.1

고분자당류인 키토산은 가식성 포장제, 항암제, 생물응집제, 항균물질등으로 폭넓은 이용성을 갖는다. 다량으로 폐기되고 있는 갑각류의 껍질을 효율적으로 이용하기 위하여 꽃게 껍질에서 키틴을 분리정제한 후 탈아세틸화하여 키토산을 제조하였다. 제조된 키토산은 탈아세틸과정 중 NaOH의 농도와 처리시간에 비례하여 탈아세틸화도가 증가하며, 저분자화되는 경향을 보였다. 대장균, Escherichia coli O157:NM을 공시균으로 하여 생육억제효과를 시험한 결과 고분자량의 키토산보다 저분자량의 키토산이 억제효과가 높았다. 이는 제조된 키토산의 항균효과가 탈아세틸화도와 분자량과 상관관계가 있음을 시사하였다. Chitosan was well known as an available material preparing for edible film, antiturmor agent, biocoagulant, and antimicrobiotics etc. For the effective use of Crustacean shell, chitin was prepared from the shell of Blue crab, and chitosan was made through the deacetylation of above chitin. Chitosan prepared from Blue crab, and showed higher degree of deacetylation and lower molecular weight according to the higher concentration and longer treatment time of NaOH in the deacetylation process. The antimicrobial effect of chitosan prepared on Escherichia coli revealed that the chitosan of lower molecular weight had of antimicrobial effect than of that higher molecular weight. The antimicrobial effect of chitosan depends on the degree of deacetylation and its molecular weight.