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>

중·고 필드하키 선수들의 스포츠 상해에 관한 연구

하태열,이기광,정종윤 창원대학교 체육과학연구소 2002 경남 체육연구 Vol.7 No.2

중·고 필드 하키선수들에게 발생하는 스포츠 상해 유형을 규명하기 위하여 2000년 제1회 중·고 연맹 회장기 대회에 참가한 남·여 하키 선수 434명을 대상으로 한 설문 조사를 분석한 결과 다음과 같은 결론을 얻었다. 첫째, 상해 빈도는 신체 부위별로 다리, 팔, 머리, 몸통 순으로 나타났다. 남·여별로는 다리부위에서는 여자, 상지부위에서는 남자가 부상 빈도가 높게 나타났다. 학교별로는 팔, 다리 부위의 부상빈도에 있어서 고등학교가 중학교보다 높게 나타났다. 위치별로는 GK가 다른 위치의 선수들보다 상대적으로 팔부위의 부상 빈도는 높고 다리 부위의 부상 빈도는 낮은 것으로 나타났다. 둘째, 상해 증상에 있어서는 피부와 근육상해가 뼈와 관절 상해 빈도의 약 3~4배 정도로 높게 나타났다. 위치별로는 유의한 차이가 나타나지 않았으나. 남자와 고등학교가 여자와 중학교에 비해서 피부와 근 상해의 빈도가 높은 것으로 나타났다. 셋째, 상해 이유에 있어서 본인 부주의에 의한 상해원인은 남자는 지나친 승부욕, 여자는 정신력 부족이 가장 높게 나타났으며, 고등학교는 과도한 연습, 중학교는 정신력부족이 가장 높게 나타났다. 시설결함에 의한 상해원인은 모두 장비 불량으로 인해 상해발생이 가장 높게 나타났으며, 장소부적응에 의한 상해원인에 있어서 모두 타구장 부적응에 의한 상해발생률이 가장 높은 것으로 나타났다.

간세포암의 십이지장침윤에 의한 상부위장관 출혈 1 예

유태현,한광협,박성하,김형길,문영명,한재호,조상호 대한소화기내시경학회 1999 Clinical Endoscopy Vol.19 No.2

Recent advances in both the diagnosis and treatment of hepatocellular carcinoma have improved the prognosis and changed the clinical significance of the recently increasing distant metastases. Distant metastases found after successful treament of the primary lesions are of great clinical significance for the treatment of hepatocellular carcinoma. The duodenum is a rare site of hematogenous metastases or direct invasion from hepatocellular carcinoma. A 23 year old man was admitted with upper gastrointestinal bleeding. He had been diagnosed with hepatocellular carcinoma and treated by a left lobectomy and chemoembolization. The patient was admittted for 12 months after the treatment of the primary tumor. Endoscopic examination revealed a mass in the duodenal bulb that protruded into the lumen. He died due to massive hematemesis. We report on a rare case of hepatocellular carcinoma with duodenal invasion in a 23-year-old male patient.

n-CdS_(0.46)Se_(0.54)/p-Cu_92-x)S_(0.46)Se_(0.54) 이종접합 태양전지의 제작과 그 특성에 관한 연구

유상하,최승평,이상열,홍광준,서상석,김혜숙,전승룡,윤은희,문종대,신영진,정태수,신현길,김택성,유기수 全北大學校 基礎科學硏究所 1994 基礎科學 Vol.16 No.-

승화방법에 의해 CdS_0.46Se_0.54 단결정을 성장하여 결정구조를 조사하고, Van der Pauw 방법으로 Hall effect를 측정하여 carrier density의 온도 의존성과 mobility의 온도 의존성을 조사하였다. 성장된 CdS_0.46Se_0.54 단결정을 치환반응하여 n-CdS_0.46Se_0.54/p-Cu_2-xS_0.46Se_0.54 이종접합 태양전지를 제작하였다. Spectral response, 전류-전압특성 및 전력변환 효율을 조사하여 그 결과로부터 개방전압은 0.48V, 단락 전류 밀도는 21mA/㎠, fill factor와 전력변환효율은 각각 0.75와 9.5%를 얻었다. CdS_0.46Se_0.54 single crystal was grown by a sublimation method. The crystal structure and the temperature dependence of carrier density and mobility of CdS_0.46Se_0.54 single crystal were studied. Heterojunction solar cells on n-CdS_0.46Se_0.54/p-Cu_2-xS_0.46Se_0.54 were fabricated by the substitution reaction. The spectral response, the J-U characteristics and the conversion efficiency of the n-CdS_0.46Se_0.54/p-Cu_2-xS_0.46Se_0.54 heterojunction solar cells were studied. The open-cricuit voltage, short-circuit density, fill factor and conversion efficiency of n-CdS_0.46Se_0.54/p-Cu_2-xS_0.46Se_0.54 heterojunction solar cells under 80mW/㎠ illumination were found to be 0.48V, 21mA/㎠, 0.75 and 9.5%, respectively.

배기가스 재순환에 의한 실린더 및 피스톤 마모에 미치는 영향에 관한 연구

황광성,김태규,정태상,김유영,하정호 진주산업대학교 산업과학기술연구소 2003 산업과학기술연구소보 Vol.- No.10

The effects of recirculated exhaust gas on the wear of cylinder liner, piston and piston rings have been investigated by the experiment with a two-cylinder, four cycle, indirect injection disel engine operating at 75% load and 1600 rpm spped. For the purpose of comparison between the wear rates of two cylinders with and without EGR, the recirculated exhaust gas is sucked into one of two cylinders after the soot among exhaust emissions is removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air into another cylinder. These experiments are carried out on the fuel injection at a fixed 15.3˚BTDC timing. It is found that firstly the mean wear amount of cylinder liner with EGR is more increased in the measurement positions of the second half than of the first and the mean wear amoount without EGR is almost uniform regardless of measurement positions, secondly the wear rates of the first and second piston ring(compression ring) thickness with EGR are more than twice, but the wear rate of oil ring thickness without EGR is more increased than that with EGR, and finally the wear rate of piston skirt with EGR is a little bit increased, but the piston head diameter is rather increased owing to soot adhesion and corrosion wear, and especially larger with EGR.

웨이브렛 신경망을 사용한 I-PD 제어계의 위치 제어

박광현,하홍곤,고태언 東義大學校産業技術開發硏究所 2003 産業技術硏究誌 Vol.17 No.-

많은 제어기법들이 이산시간영역 제어계에서 제어성능을 개선하기 위해서 제안되고 있다. 이 제어기법들을 이용한 제어계에서 계의 응답특성은 제어기의 이득에 관계한다. 특히 외란이나 부하변동에 의해서 계의 응답이 변할 때 제어기의 이득을 재조정할 필요가 있다. 본 논문에서는 I-PD 제어기를 웨이브렛과 신경망으로 설계하여 웨이브렛 신경망의 신축과 이동의 변수값을 선택하여 I-PD제어기의 이득이 자동적으로 역전파 알고리즘에 의해서 조정되도록 하였다. 이 제어기를 직류 서보 전동기를 구동원으로 하는 위치제어계에 적용하여 제어기의 제어성능을 실험을 통해 그 유효성을 검증하였다.

CROSS 공법을 이용한 폐수의 생물학적 처리에 관한 연구

박광하,심재도,권영두,강동수,김인호,정태명,황갑성 7개 국립대학교 환경연구 논문집 공동발행 위원회 2003 공업기술연구 Vol.3 No.-

This study aims to develop using a continuous removal of organic and settling solid(CROSS) to increase the efficiency of aeration system for wastewater treatment. To solve many problems of the conventional activated-sludge process, authors suggested a new CROSS model in conjunction with aeration systems in 1996. This system is characterized by utilizing an intensive aeration pipe with inlets at the lower portion and outlets at the higher portion in an aeration tank. Through the experiments on CROSS process, the average removal efficiences of BOD, COD_(Mn), SS, T-N and T-P were showed 98.8%, 93.9%, 98.0%, 71.3% and 49.8%. The average DO (Dissolved-Oxygen) concentration was constantly maintained at 8.0 mg/L by the intensive aeration which was accompanied by rapid reduction of BOD. Degradation of the organic matters in sewage then continued for the whole aeration period. The process demonstrated that it was very adaptive without seeding and returning the sludge. Compared to the activated sludge system, the system was very flexible for the continuous flow treatment. This preliminary assessment showed that the porous media in CROSS reactor is viable for the sewage treatment, since the porous media under the intensive aeration achieves acceptable effluent quality.

레이저 형광법에 의한 프로세싱 플라즈마중의 입자 계측에 관한 연구

최상태,이광식,하장호,전용우,박원주 嶺南大學校 工業技術硏究所 1998 工業技術硏究所論文集 Vol.26 No.2

Armorphous materials have various structures that is determined by different manufacturing conditions. That is, the photoelectric characteristics of films manufactured by different conditions are totally different. The growth mechanism of a-Si should be understood in order to controll the characteristics and structures of these kinds of materials. In this study, we try to elucidate the particle behaviours in a processing plasma using a low pressure glow discharge. And because of difficulties understanding discharge mechanism, we have done the processing so far depending on the experimental methods that compare the thin film produced by varing discharge parameter with the results of micromachinary. But, this has a limitation in the development because it regards the plasma as a blackbox. Therefore, because it needs to observe the discharge parameters and plasma background gas systematically, we try make sure that the particle behaviours be made clean by using laser fluorescence method which is predominant in a phenomina measurement and special resolution.

이동 애드 혹 네트워크에서 QoS를 지원하는 AODV 라우팅 프로토콜

吳世德,趙榮泰,丁燦赫,金玄郁,李光培,姜景仁,朴京培,文泰洙,郭承郁,河載承 明知大學校 産業技術硏究所 2003 産業技術硏究所論文集 Vol.22 No.-

Abstract - In this paper, we propose a bidirectional mobile Ad Hoc routing protocol based on AODV(ad-hoc on-demand distance victor routing) with QoS(quality of service) support. At presence, wireless mobile communication focuses on how to efficiently support mobility of users more than QoS guarantee. However, in order to satisfy requirement of various applications which have been or will be served, QoS guarantee between end point is a very important issue. The existing AODV routing protocol is implemented to use only BE (Best Effort) service. However, actual wireless mobile environment requires to reduce a waste of communication resources and meet with the real-time change of data paths by setting up routes with QoS support, considering available communication resources at each node in advance. Therefore, in this thesis, we propose an adaptive QoS support method using hello message in order to rapidly meet with the change of available communication resources and to smoothly perform route maintenance. For performance evaluation, we analyzed the average date reception rate. At that time, we used evaluation parameters such as node's mobility -stop time, hello message period, and packet priority, considering the node's mobility and the number of best effort/QoS data flows. As results, we found that with our proposed method the average data reception rate was increased 16.3% for 0 mobility-stop second case and 4.7% for 300 mobility-stop second case.

단계적 온도 하강법을 이용한 췌도세포 냉동보존법

정인경,오승훈,김병준,양태영,이병완,하창영,노정현,정재훈,민용기,이명식,이문규,김광원 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.26 No.1

연구배경:최근 당뇨병의 새로운 치료법으로 시도되고 있는 췌도이식은 충분한 췌도수의 확보와 췌도생존율을 높이기 위한 면역억제제 사용이 제한점이 되고 있다. 본 연구의 목적은 이식 전 충분한 췌도 수의 확보를 위해 분리한 췌도를 냉동보존하는 방법을 확립하고 냉동보존한 백서 췌도세포의 시험관내 그리고 생체내 기능을 조사하였다. 방법:분리한 백서의 췌장소도를 48시간 배양한 후 한 시험관당 췌도세포 1000개씩 나누었다. 냉동보존은 6개의 시험관에 DMSO를 첨가한 후 초 냉각(supercooling), 핵화(nucleation)단계를 거친 후 99% isopropanol과 액체질소가 들어있는 dewer를 이용하여-0.25℃/분의 냉각속도로 -40℃까지 단계적으로 얼린후-70℃ 액체질소 탱크에 보관했다. 해동은 냉동시킨 vial들을 액체 질소 태으에서 꺼내 37℃ 항온조에 담가 급격히 해동시킨 후, 원심분리하여 상층액을 제거하고 각 vial에 0.75M sucrose 용액을 가한 후, 10% fetal calf serum이 함유된 RPMI 1640 media에서 배양하였다 각각 6개의 시험관에서 해동한 췌도들을 광학현미경 및 형광현미경하에서 췌도의 모양과 생존율에 대해 조사하고 인슐린 정적반응을 알아보았다. 또한 분리한 췌도를 냉동보존하지 않고 이식한 경우를 대조군(6마리)과 생체내 기능을 비교하였다. 결과:① 냉동보존후 획득한 췌도의 수와 생존율 해동후 획득한 췌도의 수는 해동시킨 당일날이 902±21, 24시간 배양 후에는 857±16, 72시간 후에는 817±18개로 점차 감소되었다. AO/PI 염색상 각 췌도의 생존율은 냉동 전을 100으로 하였을 때 해동당일, 24시간 후, 72시간 후가 각각 60±5, 80±5, 90±5%로 해동후 3일간 배양하였을 때 냉동전의 수준으로 회복하였다. ② 냉동보존후 췌도의 포도당에 대한 정적 인슐린 분비능:냉동직후 감소된 경향을 보였으나 해동후 3일간 배양한 췌도의 인슐린 분비는 냉동전과 통계적으로 의미있는 차이가 없이 냉동보존 전의 수준으로 회복되었다. ③ 냉동보존후 췌도의 포도당에 대한 동적 인슐린 분비능:냉동보존한 췌도를 해동후 3일째의 인슐린 동적 분비능은 냉동 전과 마찬가지로 자극 인슐린의 반응의 제1기와 2기가 잘 관찰되었다. ④ 냉동보존한 췌도세포 이식 후 혈당 변화:스트렙토조토신으로 유도된 당뇨병 쥐에 췌도이식 후 혈당은 냉동보존한 췌도이식군에서 대조군에 비해 혈당의 조절효과가 더 오래 지속되었다. 결론:소동물에서 단계적 온도 하강법을 이용한 췌도세포 냉동보존법을 확립하였으며 이는 기능, 구조 및 생존율에 큰 이상을 보이지 않았으므로 장차 사람의 췌도세포 동종이식시 부족한 췌도세포수를 극복하고 면역반응을 줄일 수 있는 매우 유용한 방법이 될 것으로 판단된다. Background : Although islet transplantation has been attempted to reverse the state of diabetes, achieving a critical number of islets and modulating the immune response limit the success of islet transplantation. Cryo-preservation of islets offers many important benefits for islet transplantation by collecting islets with a wide variety of HLA phenotypes and islet MHC expression. The aims of this study was to determine the optimal conditions for cryo-preservation by using a controlled cooling method and to evaluate in vitro and in vivo functional properties of the cryo-preserved islets. Methods : Collagenase-isolated, Ficoll-purified islets were cultured for 48 hours. They were aliquoted into freezing tubes (1000 islets per tube), equilibrated with 2M dimethyl sulfoxide (DMSO) in three steps, supercooled, nucleated, and controll-cooled at rate of 0.25℃/min to - 40℃ prior to storage at - 196℃. Rapid thawing and removal of DMSO with 0.75 M sucrose preceded 48 hour of culture and the morphology, viability, glucose-induced insulin secretion, and in vivo function of rats transplanted with cryopreserved islets was reexamined. Results : ① Recovery was 90.2±0.2%, 85.7±0.1% and 81.7±0.1% immendiately after, 24 hours and 72 hours after thawing respectively. The viability was 60±5%, 80±5%, 90±5% immediately after, 24 hours and 72 hours after thawing respectively. ② The glucose-stimulated-insulin secretion (GSIS) tended to decrease immediately after thawing, but GSIS increase to the level of pre-cryopreservation 72 hours after thawing. ③ The in dynamic GSIS, the first and the second phase of insulin secretion were well preserved in islets cultured for 72 hours after thawing. ④ The cryopreserved islets were cultured for 3 days and transplanted into renal sub-capsular space of streptozotocin (STZ) induced diabetic rats. The duration of normoglycemia in the STZ-induced diabetic rats transplanted with cryopreserved islets was significantly longer than of the fresh islets. Conclusion : The optimal condition of cryopreservation using the controlled cooling method was established in rat pancreatic islets. This cryopreservation method can be a feasible approach for human islet transplantation (J Kor Diabetes Asso 26:64~74, 2002).