후면 형상에 따른 결정질 실리콘 태양전지의 후면전계 형성 및 특성

김현호,김성탁,박성은,송주용,김영도,탁성주,권순우,윤세왕,손창식,김동환,Kim, Hyun-Ho,Kim, Seong-Tak,Park, Sung-Eun,Song, Joo-Yong,Kim, Young-Do,Tark, Sung-Ju,Kwon, Soon-Woo,Yoon, Se-Wang,Son, Chang-Sik,Kim, Dong-Hwan 한국재료학회 2011 한국재료학회지 Vol.21 No.5

To reduce manufacturing costs of crystalline silicon solar cells, silicon wafers have become thinner. In relation to this, the properties of the aluminium-back surface field (Al-BSF) are considered an important factor in solar cell performance. Generally, screen-printing and a rapid thermal process (RTP) are utilized together to form the Al-BSF. This study evaluates Al-BSF formation on a (111) textured back surface compared with a (100) flat back surface with variation of ramp up rates from 18 to $89^{\circ}C$/s for the RTP annealing conditions. To make different back surface morphologies, one side texturing using a silicon nitride film and double side texturing were carried out. After aluminium screen-printing, Al-BSF formed according to the RTP annealing conditions. A metal etching process in hydrochloric acid solution was carried out to assess the quality of Al-BSF. Saturation currents were calculated by using quasi-steady-state photoconductance. The surface morphologies observed by scanning electron microscopy and a non-contacting optical profiler. Also, sheet resistances and bulk carrier concentration were measured by a 4-point probe and hall measurement system. From the results, a faster ramp up during Al-BSF formation yielded better quality than a slower ramp up process due to temperature uniformity of silicon and the aluminium surface. Also, in the Al-BSF formation process, the (111) textured back surface is significantly affected by the ramp up rates compared with the (100) flat back surface.

망간단괴 매트상 모의 침출용액으로부터 용매추출-전해채취 공정에 의한 구리의 회수

김현호,박경호,남철우,윤호성,김민석,김철주,박상운,Kim, Hyun-Ho,Park, Kyung-Ho,Nam, Chul-Woo,Yoon, Ho-Sung,Kim, Min-Seuk,Kim, Chul-Joo,Park, Sang-Woon 한국자원리싸이클링학회 2016 資源 리싸이클링 Vol.25 No.1

망간단괴 매트상 침출액 조성으로 제조 된 모의 용액(Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L)으로부터 용매추출-전해채취 연속공정을 통해 구리를 분리-회수하기 위하여 규모 확대용 용매추출장치인 6단 혼합-침강기(mixer-settler : 추출 4단, 탈거 2단)와 전해조를 이용하였다. 용매추출의 경우 추출제로는 40%(v/v)의 LIX 84I, 탈거용액은 전해폐액(Cu 35.0 g/L, $H_2SO_4$ 180 g/L)을 사용하였으며 추출단과 탈거단의 O/A 비는 각각 1/1과 1.5/1 이었다. 용매추출공정의 구리의 추출율과 탈거율은 각각 96.7%와 91.0%이었으며 탈거액(전해액)의 구리, 니켈, 코발트 그리고 철의 농도는 각각 50~51 g/L, 25 ppm, 5 ppm 그리고 3 ppm 이었다. 전해채취공정은 $1.50A/dm^2$의 전류밀도에서 98.9%의 전류효율을 나타내었으며, 99.833% 순도의 금속 구리를 얻었다. A scale-up test with a continuous solvent extraction and electro-winning system was carried out to separate and recover copper from a synthetic sulfuric acid solution (Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L). The solution was introduced into mixer-settlers with four stages of extraction and two stages of stripping for continuous countercurrent solvent extraction to separate copper from nickel and cobalt. The loading was carried out using 40% LIX 84-I(v/v) as extractant with a phase ratio of A : O = 1 : 1. Meanwhile, the stripping was undertaken at a phase ratio of A : O = 1 : 1.5 using depleted electrolyte containing 35.0 g/L Cu and 180 g/L $H_2SO_4$ as stripping solution. The extraction and stripping efficiencies were found to be 96.7% and 91.0%, respectively. The copper composition of the stripped solution (pregnant electrolyte) was 50.0 g/L Cu with impurities of 25 ppm nickel, 5 ppm cobalt and 3 ppm iron. In the electro-winning process, copper metal of 99.833 purity was yielded with current efficiency of 98.9% and current density of $1.50A/dm^2$.

용매추출-전해채취법에 의한 망간단괴 매트상 모의 침출용액으로부터 코발트 회수

김현호,남철우,박경호,윤호성,김민석,김철주,박상운,Kim, Hyun-Ho,Nam, Chul-Woo,Park, Kyung-Ho,Yoon, Ho-Sung,Kim, Min-Seuk,Kim, Chul-Joo,Park, Sang-Woon 한국자원리싸이클링학회 2016 資源 리싸이클링 Vol.25 No.2

망간단괴 매트상 모의 침출용액에서 구리 용매추출과 수산화 침전법에 의해 구리와 철이 제거 된 용액(Co 1.91 g/L, Ni 14.65 g/L)으로부터 용매추출-전해채취 연속공정을 통해 코발트를 분리, 회수를 위한 규모확대 실험(망간단괴 기준 380 kg/day)을 수행하였다. 용매추출의 경우 추출제로는 NaOH로 45% 비누화 된 0.22 M Cyanex 272, 세정용액은 코발트 2 g/L(pH : 3.0), 탈거용액은 코발트 전해폐액(Co 36.0 g/L, $Na_2SO_4\;70g/L$, pH : 1.5)을 사용하였으며, 탈거된 유기상은 산과 증류수의 세척 공정을 통해 재사용하였다. 추출단, 세정단 그리고 탈거단의 O/A 비는 각각 1/1.5, 10/1 그리고 1.5/1 이었으며, 산세척과 수세척단의 O/A 비는 각각 1/1, 6/1이었다. 용매추출공정의 코발트의 추출율과 탈거율은 각각 99.8%와 99.88%이었으며 탈거액의 코발트와 니켈의 농도는 각각 40.27 g/L, 4 ppm이었다. 전해액의 pH 조절을 위해 전해폐액 순환 방식을 도입한 전해채취공정은 $0.563A/dm^2$의 전류밀도에서 67.0%의 전류효율을 나타내었으며, 99.963% 순도의 금속 코발트를 얻었다. A scale up tests (380 kg/day) using a continuous solvent extraction and electro-winning system was carried out to separate and recover cobalt from a solution containing 1.91 g/L Co and 14.65 g/L Ni. The solution was obtained during a process including solvent extraction and precipitation stages for removal of Cu and Fe from a synthetic sulfuric acid solution of manganese nodule matte. The optimal condition for solvent extraction was : solvent concentration of 0.22M Na-Cyanex 272 (45% saponified with NaOH) and O:A phase ratios of 1:1.5, 10:1 and 1.5:1 used in extraction, scrubbing and stripping stages, respectively. The extraction and stripping efficiencies were found to be 99.8% and 99.88%, respectively. The stripped solution contained 40.27 g/L Co with 4 ppm Ni. Cobalt metal of 99.963% purity was yielded with current efficiency of 67% and current density of $0.563A/dm^2$ during the electro-winning process.

요추(腰椎) 추간판(椎間板) 탈출증(脫出症)으로 인하여 발생한 소음인(少陰人) 요각통(腰脚痛) 치험 1례

김현호,김은이,김경선,임은철,정경숙,윤형선,Kim, Hyun-Ho,Kim, Eun-Yi,Kim, Kyung-Sun,Lim, Eun-Chul,Jung, Kyung-Suk,Yoon, Hyoung-Seon 사상체질의학회 2004 사상체질의학회지 Vol.16 No.3

1. Objectives The purpose of this study is to give an account of the effects of Korean herbal medicine therapy which is based on the Sasang Constitutional Medicine for the patient who has suffered from low back pain caused by the Herniated Lumbar Disc. 2. Methods Consulting her sungjeong(性情), Chehyungkisang(體形氣像) and QSCCII, we have diagnosed her as Soeumin(少陰人), and have prescribed Hyangbujapalmul-tang(香附子八物湯). 3. Results After the treatment, she felt her symptoms, low back pain, headache, and general condition, improved. 4. Conclusions This paper describes the process of management and changes of symptoms. We hope this paper useful to rehabilitatable treatment for low back pain caused by the Herniated Lumbar Disc through Sasang Constitutional Medicine.

이중합성 교량의 복합스터드 전단연결부의 정적강도 평가

김현호,심창수,윤광중,이필구,Kim, Hyun Ho,Shim, Chang Su,Yun, Kwang Jung,Lee, Pil Goo 한국강구조학회 2005 韓國鋼構造學會 論文集 Vol.17 No.5

철도교는 강성이 주요한 설계인자이기 때문에 기존의 2거더 교량의 구조적 효율성을 높이기 위해서 이중합성 구조를 가진 철도교를 제안하였다. 일반적으로 강합성 연속교를 설계할 경우, 부모멘트 구간에 존재하는 콘크리트 바닥판은 인장에 저항하지 못한다고 가정하고 바닥판 단면을 무시하게 된다. 부모멘트 구간에서는 합성단면의 강성이 감소하게 되므로 이를 보완하기 위해 강재단면이 커지게 되는데, 이러할 경우 변단면의 적용이 불가피하게 되고 강합성형으로서의 장점이 반감된다고 할 수 있다. 이와 같은 문제점을 해결하기 위한 다양한 접근법이 존재하지만 그 중에서도 경간을 확대하고 강성이 중요한 설계인자가 되는 경우에 적절하게 사용될 수 있도록 제안된 교량의 형태가 이중합성구조이다. 따라서 본 연구에서는 이중합성 전단연결부의 거동을 파악하기 위하여 수평스터드, 수평스터드와 수직스터드가 함께 배치된 복합스터드 부재에 대한 push-out 실험을 수행하였다. 실험결과의 분석을 통하여 기존의 설계식과의 비교를 수행하고 정적 거동을 평가하였다. A railway bridge with a double composite section is proposed to enhance the structural performance of existing two-girder bridges because the governing design parameter of railway bridges is the flexural stiffness. The concrete deck in negative moment regions is neglected in the design of continuous composite bridges assuming the concrete slab has no resistance to tension. Therefore, the flexural stiffness of the composite section in the negative moment region is reduced resulting in the increase of the depth of the steel section. In order to resolve this disadvantage, several methods are suggested and the double composite section is one of the excellent solutions for extending the span length and increasing the flexural stiffness. In this study, push-out tests on lying studs and mixed stud shear connection with lying and vertical studs were performed to investigate the behavior of the shear connection in the double composite section. Static strength of the shear connection was evaluated through the test results and numerical analyses.

Variation of Grain Traits in Landraces of Rice Collected from Vietnam

김현호,조재성,Kim, Hyun-Ho,Jo, Jae-Seong Institute of Agricultural Science 1997 Korean Journal of Agricultural Science Vol.24 No.2

베트남으로부터 수집된 총 437 벼 지역종을 사용하여 총 종자 단백질을 분석하기 위하여 SDS-PAGE와 phenol 반응을 수행하였다. 세 가지 다른 형태의 glutelin a subunit이 검출되었다. 60kDa의 분자량인 wx 단백질 수준은 세 그룹으로 분리되었는데, 이는 non-glutelin, intermediate, 그리고 glutelin 전분 유형이다 종자 저장 단백질과 wx 단백질의 변이에 의한 실험결과 지역종은 7그룹으로 구분된다. Glutelin a subunit의 A와 B형의 빈도분포는 벼 지역종이 수집된 위도에 따라서 변하였다. 페놀 반응에 대한 지리학적인 구배가 검출되었다. A total of 437 landraces of rice from Vietnam were analyzed for total seed protein by SDS-PAGE and phenol reaction. The different types of glutelin $\alpha$ subunits were detected. The level of wx protein with 60kDa molecular weight was divided into 3 groups, corresponding to non-glutinous, intermediate and glutinous starch types. Based on the variation in seed storage protein and wx protein, landraces were classified into 7 groups. Frequency distribution of types A and B of glutelin $\alpha$ subunits changed with the latitude at which rice landraces were collected. Geographical cline for phenol reaction was detected.

눈물점마개를 이용한 눈물샛길의 치료

김현호,정병진,신동수,이규원,Hyun Ho Kim,Byung Jin Jeong,Dong Su Shin,Kyoo Won Lee 대한안과학회 2007 대한안과학회지 Vol.48 No.4

Purpose: To evaluate the results and complications of the punctal plug insertion through lacrimal fistula. Methods: Four patients diagnosed with congenital lacrimal fistula had a punctual plug inserted through the lacrimal fistula without anesthesia from January to May 2005. Results: Mean follow-up period was 6.8 months. In two pediatric patients whose mean age was 5.0 years, the fistula was not associated with nasolacrimal duct. In two adult patients, it was associated nasolacrimal duct obstruction, whose mean age was 49.0 years. In all cases epiphora improved. There was a puncal plug prolapse in one case and no other complications. Conclusions: Punctal plug insertion is considered a simple and useful technique for lacrimal fistula without congenital nasolacrimal obstruction in children especially whose parents refuse general anesthesia. Punctal plug insertion can be useful to reduce scarring in adult patients that receive endoscopic dacryocystorhinostomy with nasolacrimal obstruction.

결막이완증에서 지짐술과 봉합술의 병행효과 4예

김현호,신동수,이규원.Hyun Ho Kim. M.D.. Dong Su Shin. M.D.. Kyoo Won Lee. M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.5

Purpose: We performed cauterization and suturing without resection and evaluated the technique`s efficacy in the treatment of conjunctivochalasis. Methods: Four eyes of three patients diagnosed with conjunctivochalasis were treated with cauterization and suturing. After opening the eyelids, the loosened bulbar conjunctiva was pulled down tensely. After local anesthesia near the inferior fornix (about 8 mm below the limbus), the bulbar conjunctiva and Tenon`s capsule were gripped together by bipolar cautery (UM 150A). The cauterization was performed in one second. Still gripped by the bipolar cautery, the bulbar conjunctiva and Tenon`s capsule were fixed to the sclera with Vicryl 6-0. Identical procedures were performed on two other sites along the inferior fornix. The suture stitch were removed 10 days after the surgical procedure. Results: The objects were 4 eyes of 3 patients (1 male, 2 females with an average age of 63 years). The mean follow-up period was 4 months. There were no recurrences or any postoperative complications caused by cauterization. Conclusions: We successfully treated conjunctivochalasis with a simple procedure of conjunctival fixation to the sclera through cauterization and suturing.

무선 ad-hoc 네트워크 환경에서 균형화된 에너지 소비를 위한 효율적인 라우팅 알고리즘

김현호,김정희,강용혁,엄영익,Kim, Hyun-Ho,Kim, Jung-Hee,Kang, Yong-Hyeog,Eom, Young-Ik 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.11A

무선 ad-hoc 네트워크 환경에서 이동 호스트의 배터리 수명을 최대화하는 것은 시스템의 수명과 성능을 향상시키므로 매우 중요하다. 이동 호스트들은 라우팅 역할을 수행하므로 네트워크의 구조와 이동 호스트들의 위치에 따라 이동 호스트들의 에너지 소비의 차이가 발생된다. 본 논문에서 각 이동 호스트는 에너지 트리를 유지하며, 메시지 트리 패킷을 이용하여 이웃 이동 호스트들의 에너지의 양을 주기적으로 파악한다. 이동 호스트는 패킷을 전송하기 위한 라우팅 경로를 설정할 때 에너지 트리와 너비우선 탐색을 이용하여 에너지 소비가 가장 적절한 경로를 선택한다. 제안기법은 무선 ad-hoc 네트워크 환경에서 각 이동 호스트의 에너지의 양이 균등하게 사용됨으로써 제한된 배터리 용량을 가진 이동 호스트들이 최대한 오랫동안 동작하므로 시스템의 수명과 성능을 향상시킨다. It is very important to maximize the battery durability of mobile host in wireless ad-hoc network environments, because it extends the durability and Performance of the system. Since mobile hosts play a routing role, the network structure and the location of mobile hosts create a difference of energy consumption of mobile hosts. In this paper, each mobile host maintains energy tree and evaluates the amount of the energy of the neighboring mobile hosts by using message tree packet by periods. When mobile host sets up a routing path to send a packet, it selects the most proper path in order to consume energy effectively by using energy tree and breadth first search. In this paper, we suggest that, in wireless ad-hoc network environments, if each mobile host consumes balanced energy, mobile hosts of which energy capacity is limited can work as long as it can. Therefore, the durability and performance of the system can be extended.

반응성 스퍼터링법으로 형성시킨 PZT 커패시티의 P-E 이력곡선의 이동현상 및 피로 특성 연구

김현호,이원종,Kim, Hyun-Ho,Lee, Won-Jong 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.11

[ $PZT(Pb(Zr,Ti)O_3)$ ] thin films were deposited by multi-target reactive sputtering method on $RuO_2$ substrates. Pure perovskite phase PZT films could be obtained by introducing Ti-oxide seed layer on the $RuO_2$ substrates prior to PZT film deposition. The PZT films deposited on the $RuO_2$ substrates showed highly voltage-shifted hysteresis loop compared with the films deposited on the Pt substrates. The surface of $RuO_2$ substrate was found to be reduced to metallic Ru in vacuum at elevated temperature, which caused the formation of oxygen vacancies at the initial stage of PZT film deposition and gave rise to the voltage shift in the P-E hysteresis loop of the PZT capacitor. The fatigue characteristics of the PZT capacitors under unipolar wane electric field were different from those under bipolar wane. The fatigue test under unipolar wane showed the increase of polarization. It was thought that the ferroelectric domains which had been pinned by charged defects such as oxygen vacancies and the charged defects were reduced in number by combining with the electrons injected from the electrode under unipolar wave, resulting in the relaxation of the ferroelectric domains and the increase of polarization.