• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.1-8
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• 2006

Higher density integration and adoption of new materials in advanced electronic package systems result in severe electrochemical reliability issues in microelectronic packaging due to higher electric field under high temperature and humidity conditions. Under these harsh conditions, metal interconnects respond to applied voltages by electrochemical ionization and conductive filament formation, which leads to short-circuit failure of the electronic package. In this work, in-situ water drop test and evaluation of corrosion characteristics for SnPb solder alloys in D.I. water and NaCl solutions were carried out to understand the fundamental electrochemical migration characteristics and to correlate each other. It was revealed that electrochemical migration behavior of SnPb solder alloys was closely related to the corrosion characteristics, and Pb was primarily ionized in both D.I. water and $Cl^{-}$ solutions. The quality of passive film formed at film surface seems to be critical not only for corrosion resistance but also for ECM resistance of solder alloys.

• Journal of Korean Medical classics
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• v.18 no.2 s.29
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• pp.1-19
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• 2005

통과대명대저명의가(通過對明代著名醫家), 온보파창시자설기(溫補派創始者薛己)$(1487{\sim}1559)$적생애화의학사상(的生涯和醫學思想), 득출여하결론(得出如下結論): 설기생여의학세가(薛己生於醫學世家), 종소학습유학화의학(從小學習儒學和醫學), 기부사후(其父死後), 체부진입태의원성료의사(替父進入太醫院成了醫士), 지후선후역임태의원이목(之後先後歷任太醫院吏目), 남경태의원원판(南京太醫院院判), 원사등직(院使等職), 병어1540년(44세)기관회향(幷於1540年(44歲)棄官回鄕), 전심여치료환자여저술(專心於治療患者與著述). 설기적저작대부분내(薛己的著作大部分內) 용이의안형식서사(容以醫案形式書寫), 기내용포함내과(其內容包含內科), 외과(外科), 부산과(婦産科), 소아과(小兒科), 침구과(鍼灸科), 치과(齒科), 안과(眼科), 골과(骨科), 본초등(本草等). 기본인친(其本人親) 자저술적유이(自著述的有以)${\ulcorner}$내과적요(內科摘要)${\lrcorner}$위시약12종(爲始約12種), 교주적유이(校注的有以)${\ulcorner}$부인대전양방(婦人大全良方)${\lrcorner}$위시8종(爲始8種), 교감적의서약유6종(校勘的醫書約有6種), 공계대약(共計大約) 유26종지다(有26種之多). 설기수(薛己受)${\ulcorner}$내경(內經)${\lrcorner}$, ${\ulcorner}$난경(難經)${\lrcorner}$급장원소화금원사대가적영향교심(及張元素和金元四大家的影響較深). 재사대가중(在四大家中), 우기수동원화단계적영향최심(尤其受東垣和丹溪的影響最深). 차외(此外), 가지기수교주의서적영향역교대(可知其受校注醫書的影響亦較大), 기통과박람군서(其通過博覽群書), 대담실천(大膽實踐), 광수자료(廣收資料), 선우총결(善于總結), 최종성료일명의가(最終成了一名醫家). 설기수이동원(薛己受李東垣)${\ulcorner}$비위론(脾胃論)${\lrcorner}$적영향(的影響), 강조비위적중요성(强調脾胃的重要性), 병수차제출비통혈적이론(幷首次提出脾統血的理論) 기여이동원적학설부동지처시(其與李東垣的學說不同之處是), 재치료화쇠토약형허한증시(在治療火衰土弱型虛寒證時), 주장이보화생토지법내치료(主張以補火生土之法來治療), 인위비여신적생리작용호위관련(認爲脾與腎的生理作用互爲關聯), 비토화생정미(脾土化生精微), 이자양신여명문(以滋養腎與命門) 반과래(反過來), 신여명문역대위토기온후작용(腎與命門亦對緯土起溫煦作用); 이재병리방면(而在病理方面), 비토구허(脾土久虛), 가치신허(可致腎虛), 신허즉불능생토(腎虛則不能生土), 역가치비허(亦可致脾虛). 설기적극반대명대의가수금원지유풍(薛己積極反對明代醫家受金元之遺風), 이한양약공하(以寒凉藥攻下), 혹남용지백이강화(或濫用知柏以降火), 극벌생기적작법(克伐生氣的作法), 이주장용편온적약물진행조보(而主張用偏溫的藥物進行調補), 기상용적전인처방유보중익기탕(其常用的前人處方有補中益氣湯), 사물탕(四物湯), 사군자탕(四君子湯), 육군자탕(六君子湯), 독삼탕(獨蔘湯), 삼부탕(蔘附湯), 육미환(六味丸), 팔미환(八味丸), 신기환(腎氣丸), 회양탕(回陽湯), 당귀보혈탕등(當歸補血湯等).

• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.209-230
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• 2014

There are three forms of REITs company in Korea that was first introduced in 2002. Each REITs have been listed on the KRX, its characteristics are different, but it is classified as a REITs company in all events. REITs current methods are applied uniformly manner that does not reflect the characteristics of the individual. REITs some, that is not seen unlike legislative intent, it is delisted, such as generating an investment loss of investors. In this study it is an object of the invention from the point of view of REITs business validity, to draw up operational support aggressive plans of the scheme. By improving the PF assesment system, to improve the relevance of REIT business and presenting policy direction to the activation of REITs. Through the sophistication of real estate finance utilizing REITs, policy for proper investment of general investors REITs funds were listed with the smooth flow must be realized. The results of this study, it can be utilized as basic data for policy to reflect the real estate policy for activation of the indirect financial investments.

• Journal of the Korean Electrochemical Society
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• v.5 no.2
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• pp.52-56
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• 2002

Tin oxide was coated on graphite particle by sol-gel method and an electrode with this material having microcrystalline structure for lithium ion battery was obtained by heat treatment in the range $400-600^{\circ}C$. The content of tin oxide was controlled within the range of $2.25wt\%\~11.1wt\%$. The discharge capacity increased with the content of tin oxide and also initial irreversible capacity increased. The discharge capacity of tin oxide electrode showed more than 350 mAh/g at the initial cycle and 300 mAh/g after the 30th cycle in propylene carbonate(PC) based electrolyte whereas graphite electrode without surface modification showed 140 mAh/g. When the charge and discharge rate was changed from C/5 to C/2, The discharge capacity of tin oxide and graphite electrode showed $92\%\;and\;77\%$ of initial capacity, respectively. It has been considered that such an enhancement of electrode characteristics was caused because lithium $oxide(Li_2O)$ passive film formed from the reaction between tin oxide and lithium ion prevented the exfoliation of graphite electrode and also reduced tin enhanced the electrical conduction between graphite particles to improve the current distribution of electrode.

• Applied Chemistry for Engineering
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• v.17 no.6
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• pp.575-579
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• 2006

Solid electrolyte interface is formed on a carbon electrode used as an anode in Li-ion battery, which can be of $Li^{+}$ intercalation/deintercalation during the first cycle. The passivation film formed by a solvent decomposition during the initial charge process affects cell performance and it was one of the main reason of an initial irreversible capacity. This paper describes the use, for the first time, of $Li_2CO_3$ as the additive for the formation of a passivation film on the carbon surface to suppress the initial irreversible reaction. Chronopotentiometry, cyclic voltammetry, and impedance spectroscopy were used to investigate the effects of the $Li_{2}CO_{3}$ additive. Scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction were also used to monitor changes in the surface morphology and composition of the passivation film formed by solvent decomposition and the precipitation of $Li_{2}CO_{3}$. The addition of $Li_{2}CO_{3}$ to a solution of 1 M $LiPF_{6}$/EC:MA (1:3, v/v) resulted in a decrease in the initial irreversible capacity and it was due to the suppression of the solvent decomposition on the electrode surface.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.400-408
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• 2003

Chloride ion inside concrete destroys the so-called passive film surrounding reinforcing bars inside concrete so that the so-called salt attack accelerates corrosion which is the most critical factor for durability as well as structural safety of reinforced concrete structures. Recently, as a solution of the salt attack, the ground granulated blast-furnace slag(GGBFS) have been used as binder or blended cement more extensively. In this paper, characteristics of chloride ion diffusion for the GGBFS concrete, which is known to possess better resistance to damage due to the chloride ion penetration than ordinary portland cement(OPC) concrete possesses, are analyzed and a chloride ion diffusion model for the GGBFS concrete is proposed by modifying an existing diffusion model for the OPC concrete. The proposed model is verified by comparing diffusion analysis results using the model accelerated chloride penetration test results for concrete specimens as well as field test results for an RC bridge pier. Then, an optimal resistance condition to chloride penetration for the GGBFS concrete is obtained according to degrees of fineness and replacement ratios of the GGBFS concrete. The result shows that the GGBFS concrete has better resistance to chloride ion penetration than OPC concrete has and the resistance is more affected by the replacement ratio than the degree of fineness of the GGBFS.

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.136-140
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• 2000

A stainless steel separator for a molten carbonate fuel cell is usually coated with aluminum diffusive layer to protect its surface against corrosion by the molten carbonate at high temperatures. In this study, a relatively simple method was devised to form the aluminum diffusive layer on a stainless steel substrate. Slurry coating of aluminum on the substrate followed by heat treatment under reducing atmosphere at $650\~800^{\circ}C$ produced the aluminum diffusive layer of $25\~80{\mu}m$ thickness. The thickness of aluminum diffusive layer increased with increasing the temperature or duration of the heat-treatment. The corrosion resistance against molten carbonate under oxidizing atmosphere was significantly improved by aluminum diffusive layer formed by the sluny painting and heat treatment method. Moreover, the sample prepared in this study showed corrosion behavior similar to the sample with aluminum diffusive layer prepared by ion vapor deposition and heat treatment.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.470-483
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• 2003

This study analyzed the evolutionary content in 13 textbooks developed from the first to the 6th high school biology curriculum, The content analysis of textbooks, which were delineated nine component, was performed on the 80 evolutionary categories, According to the result, the proportion of the total evolutionary content in textbook increased from the textbooks developed by the Ist curriculum to the textbooks developed by the 6th curriculum, but the proportion of 'main narrative' in total evolutionary content was gradually decreased. It also showed that biology curriculum and points of view of textbook writers influenced on the proportion of evolutionary contents. On the whole, the topics of analysed textbooks exhibit insufficient diversity, Any categories- 'group selection', 'gene selection', 'gaps in fossil record', 'co-evolution', 'punctuated equilibrium', 'mosaic evolution', 'place of labor in human evolution', 'human race differentiation', 'criticism of "ontogeny recapitulates phylogeny", and 'human activities affecting evolution' - were not treated and others - 'theory of neutralism', 'theories of major episodes(excepting extinctions) found in the geologic time scale', 'sympatric speciation', 'clinal and area-effect speciation', 'polyploidy and evolution', 'gradualism' and 'evolution and origin of mammals' - were treated very lightly, the most emphasized topic was 'phylogeny in general' and 'formation of precells', 'miscellaneous' in the order of emphasis. 'Theory of natural selection' was lightly treated as just one of evolutionary theory though it should be emphasized as major theme of evolution. Also, the law of recapitulation, of which biologists doubt the validity, was discussed as an evidence of evolution in some textbooks. And the agents of genetic equilibrium disruption like genetic drift and migration were treated as of little importance. On the basis of above result, it was suggested that the textbook writers introduced the more meaningful evolutionary topics focused the theory of natural selection in explanation of evolution and evolution theory.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.11a
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• pp.72-72
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• 1998

원자력발전소 1차계통내 밸브의 경면처리(hardfa따1잉에 사용되는 재료는 $90~343^{\circ}C$의 고온과 높은 접촉응력 그리고 급격한 압력변화가 일어나는 환경에서 사용되기 때문에 내마모성과 내식성 그리고 cavitation erosion 저항성이 우수한 Co계 Stellite 합금이 현재 사용되어진다. 그러나 Co가 원력발전소 1차계통의 방사선장을 형성하는 주요 원소로 알려지면서 S Stellite 합금을 대체할 수 있는 Fe계 경면처리용 합금을 개발하려는 연구가 진행되고 있다. 현재 Fe계 경면처리용 합금의 개발은 적절환 팝금원소를 첨가하여 적충결함에너지를 낮춤 으로써 전위의 교차슬립을 억제하여 표면을 경화시키고, 소성변형을 억제하여 마모저항성을 향상시키려는 방법으로 연구가 진행되고 있다. 본 연구에서는 Fe-Cr-Ni-Si-C 합금에 Fe계 합금의 적충결함에너지를 감소시키는 것으로 알려진 vanadium을 0, 1, 2wt%첨가하여 첨가량의 변화가 cavitation erosion 저항성에 미치 는 영향을 조사하였다. Cavitation erosion 실험은 초음파를 이용하여 미세한 기포를 발생시키는 vibratory type으로 A ASTM G-32 규격에 따라 제작된 실험장치를 이용하여 $25{\pm}2^{\circ}C$의 온도의 증류수 속에 잠긴 상태에서 실시하였다. 시면은 지름 16mm, 두게 7mm의 버턴형태로 vanadium 첨가량을 변화시킨 조성을 아크 용융 방법을 이용하여 제작하였으며 hom끝단부에 부착하여 cavitation e erosion 저항성 살험을 하였다. 시편의 cavitation erosion 실험시간에 따른 무게감소량을 측 정하였으며 cavitation erosion 시킨 시편의 표면을 SEM으로 관찰하였다.겨지는 열전달 매체액 과 신규 부식억제제가 적용된 시스템 등 객관적으로 확인된 부식억제제 시스랩에 대 하여 다양한 평가 방법을 동원 비교분석하고자 하였다. 실험은 KSM 2142에 의한 무게감량법, 분극곡선 측정에 의한 $E_P$(공식개시전위), $E_R$(재부동태화전위) 측정, 시간에 따른 자연전위 변화 측정 빛 이때의 부식속도(선형분극법), 인위적인 피막 파괴 전,후 의 전위 변화 및 부식속도 측정법에 의한 국부부식 발달 저지능 등을 평가하여 각 실험결과를 비교분석하여 보았다. 수록 민감하여 304 의 IGSCC 와 매우 유사한 거동을 보인다. 본 강연에서는 304 와 600 의 고온 물에서 일어나는 IGSCC 민감도에 미치는 환경, 예민화처리, 합금원소의 영향을 고찰하고 이에 대한 최근의 연구 동향과 방식 방법을 다룬다.다.의 목적과 지식)보다 미학적 경험에 주는 영향이 큰 것으로 나타났으며, 모든 사람들에게 비슷한 미학적 경험을 발생시키는 것 이 밝혀졌다. 다시 말하면 모든 사람들은 그들의 문화적인 국적과 사회적 인 직업의 차이, 목적의 차이, 또한 환경의 의미의 차이에 상관없이 아름다 운 경관(High-beauty landscape)을 주거지나 나들이 장소로서 선호했으며, 아름답다고 평가했다. 반면에, 사람들이 갖고 있는 문화의 차이, 직업의 차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$

• Journal of Korea Technology Innovation Society
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• v.21 no.4
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• pp.1577-1605
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• 2018

This study analyzes China's technology billionaires. However, this study does not show the accumulating process of wealth in each of the Chinese billionaires, because there are many technology billionaires, but only deals with the macro analysis of the technology billionaire; the pattern of existence, comparison with other industries, the process of wealth creation reflecting China's particularity, and comparison with the world's technology billionaires. The findings of this study are as follows. First, more than 10 billion yuan of Chinese billionaires will emerge from 2004. Second, in the early days, illegal and corruption made rich, but the wealth of own efforts has gradually increased. Third, the real estate and manufacturing billionaires are still strong overall, but the growth of billionaires in technology, medicine and finance industry is remarkable. Fourth, in the case of the top 10 richest, four are from real estate, four from technology, and two from manufacturing and distribution. Most technology billionaires are in Guangdong, Zhejiang, Beijing and Shanghai. The determinants of the number of billionaires are GDP, exchange rate to US Dollar and Shenzen Stock Index, and those of technology billionaire are GDP and exchange rate. Given the relationship with existing theories, this study can be called the fifth type of billionaire research. Conceptually, the main reason for accumulating wealth is the search for policy opportunities, market opportunities and technology opportunities.