무연 BaTiO₃-(Bi_0.5K_0.5)TiO₃ PTCR 세라믹과 PTCR 특성에 미치는 Nb₂O₅의 효과

정영훈,박용준,이미재,이영진,백종후,최진수,이우영,Jeong, Young-Hun,Park, Yong-Jun,Lee, Mi-Jae,Lee, Young-Jin,Paik, Jong-Hoo,Choi, Jin-Soo,Lee, Woo-Young 한국재료학회 2008 한국재료학회지 Vol.18 No.9

Positive temperature coefficient of resistivity (PTCR) characteristics of (1-x)$BaTiO_3-x(Bi_{0.5}K_{0.5})TiO_3$ ceramics doped with $Nb_2O_5$ were investigated in order to develop the Pb-free PTC thermistor available at high temperatures of > $120^{\circ}C$. The PTCR characteristics appearing in the ($B_{i0.5}K_{i0.5})TiO_3$ (< 5 mol%) incorporated $BaTiO_3$ ceramics, which might be mainly due to $Bi^{+3}$ ions substituting for $Ba^{+2}$ sites. The 0.99$BaTiO_3-0.01(Bi_{0.5}K_{0.5})TiO_3$ ceramics showed good PTCR characteristics of a low resistivity at room temperature (${\rho}_r$) of $31{\Omega}{\cdot}cm$ a high ${\rho}_{max}/{\rho}_{min}$ ratio of $5.38{\times}10^3$, and a high resistivity temperature factor (${\alpha}$) of $17.8%/^{\circ}C$. The addition of $Nb_2O_5$ to 0.99$BaTiO_3-0.01(Bi_{0.5}K_{0.5})TiO_3$ ceramics further improved the PTCR characteristics. Especially, 0.025 mol% $Nb_2O_5$ doped 0.99$BaTiO_3-0.01(Bi_{0.5}K_{0.5})TiO_3$ ceramics exhibited a significantly increased ${\rho}_{max}/{\rho}_{min}$ ratio of $8.7{\times}10^3$ and a high ${\alpha}$ of $18.6%/^{\circ}C$, along with a high $T_c$ of $148^{\circ}C$ despite a slightly increased ${\rho}_r$ of $31{\Omega}{\cdot}cm$.

연골 조직 재생을 위한 나노섬유/알지네이트 복합 재료 스캐폴드의 제작

장진아(Jinah Jang),이종완(Jongwan Lee),설영준(Yeong-Joon Seol),정영훈(Young Hun Jeong),조동우(Dong-Woo Cho) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10

Three-dimensionally polycaprolactone(PCL) nanofiber reinforced alginate hydrogel scaffold were fabricated for the regeneration of functional cartilage construct with G-glucono-δ-lactone(GDL) cross linker that was applied to alginate hydrogel crosslinking with calcium carbonate (CaCO<SUB>3</SUB>) to maintain its structural integrity. In order to analyze new types of PCL nanofiber/alginate gel composite scaffold, four kinds of PCL nanofiber/alginate hydrogel composite scaffold were fabricated depends on the amount of nanofiber using dual-nozzle electrospinning process. Young’s moduli of each composite scaffolds were increased better than alginate only structure, also its value nearly approached normal articular cartilage. In conclusion, these results indicate feasibility of the new type of functional scaffold for cartilage regeneration from PCL nanofiber/alginate hydrogel composite scaffold.

최근의 단군관련 인식혼란과 과제

정영훈(Jeong. Young-hun) 고조선단군학회 2002 고조선단군학 Vol.7 No.-

Dangun was the ongll1 of Korean's national identity and was the symbol of Korean nation's homogeneity and national pride. For more than 700 years, Koreans thought Dangun as their ethnic ancester and historical starting point. The consciousness of Dangun's descendants changed Korean people into one modem nation. And many national integration devices like Gaecheonjeol(OOA~'rJ), one of the national holiday which commemorates the Dangun's state founding day, and Hongikingan(~L~ A.rf39), the ultimate aim of offical education which derived from Dangun mith. These phenomena can be called by Dangun nationalism. But in recent years Dangun's status as an integration simbol was weekened. Positivist hystorians insisted that Dangun's founding state was only myth and not a historically existed fad. Individualists and Universalists thought that Dangun symbol was combined with totalitarian and authoritarian ideology.Despite these attacks proper counterplans were not presented. On the contrary the recognitions of the people who were attached to Dangun became more irrational. Dangun nationalism is now nearly in cnSlS. This Article examines the actual condition of the recent cognitive confusion on Dangun and discusses the present meanings of Dangun. The author of this article thinks that Dangun is a necessary device for the 21th century's Korean people. In this article the author discusses the reasons why Dangun is required, and on this viewpoint proposes some alternatives to disentangle the chaos.

[특집-단군신화연구] 한국인의 정체성과 홍익인간이념

정영훈(Jeong Young-Hun) 고조선단군학회 2002 고조선단군학 Vol.6 No.-

This Article discusses the Hongikinghan(弘益人間) ideology in connection with the Korean's identity. Hongikinghan was the ideal of the Korean's first national foundation in 2333 B.c., and was the educational aim in the Education Law 1948 A.D.. And it means the greatest service for the benifit of humanity. In Dangun Mith(檀君神話) which depicted the progress of Korean's first founding State, Hongikinghan was described as the ideal of founding state. Seeing in this context Koreans can be explained as the people who began their history with the Hongikinghan ideology, united into community by that ideology, and accepted it as the principle of individual life. Hongikinghan was settled down as the educational ideal by the first Korean government in 1948. It can be said that from the time of begining modem history Koreans chose the Hongikinghan ideology as their principle of individual and social life, and decided it as the educational principle in raising their children. Hongikinghan pursues the life and society which helps the man broadly. So Koreans can be explained as the people who dreamed the happy community which respects man as the final aim and determined the serving life toward the neighbors and community. But if we see in the<br/> viewpoint of Hongikinghan we must say with a heavy heart that today's Koreans are living in the self-loss conditions and self-betrayal history. Today's Koreans are living under a anti-community value sense and anti-Hongikinghan thinking way such as egoistic individualism and immoral epicurism. Koreans must recover the native identity and ideals which accepted the Hongikinghan ideology as the principle of life. And Hongikinghan must be a term which dipicts the present and future identity of Korean.

이송모터 전류신호를 이용한 공구파손 검출

정영훈(Young Hun Jeong) 한국기계가공학회 2015 한국기계가공학회지 Vol.14 No.6

Tool condition monitoring plays one of the most important roles in the improvement of both machining quality and productivity. In this regard, various process signals and monitoring methods have been developed. However, most of the existing studies used cutting force or acoustic emission signals, which posed risks of interference with the machining system in dynamics, fixturing, and machining configuration. In this study, a feed motor current signal is used as a process signal representing process and tool states in tool breakage monitoring based on an adaptive autoregressive model and unsupervised neural network. From the experimental results using various cases of tool breakage, it is shown that the developed system can successfully detect tool breakage before two revolutions of the spindle after tool breakage.

『광장』과 사르트르 철학의 관련성

정영훈 ( Young Hun Jeong ) 한국현대문예비평학회 2006 한국문예비평연구 Vol.- No.21

대종교와 유교

정영훈 ( Young Hun Jeong ) 東洋哲學硏究會 2002 東洋哲學硏究 Vol.29 No.-

개천절, 그 ‘만들어진 전통’의 유래와 추이 그리고 배경

정영훈(Jeong, Young-Hun) 고조선단군학회 2010 고조선단군학 Vol.23 No.-

This paper discusses the origins, instutionalization process and background of the Gaecheon-jeol(開天節) Gaecheon-jeol is one of the national holidays of Korea. The date is October 3. It was commemorated from 1909 the late Chosun period, and was legislated as a national holiday in 1949 by Korean Government.’ Certainly the Gaecheon-jeol is a kind of ’Invenyed Tradition’. But it was not fabricated in a day. It was based on the resources which long Korean history had bequeathed. And it was not invented by state power or capital on the purpose of ruling purpose. But it was proposed by patriotic nationalists who devoted themselves to the welfare of their compatriots. It also was not invented for a power, and there are no conspiracy for domination to people. The Gaecheon-jeol started with the purpose to liberate and integrate the Korean people. And the hopes of Korean people to make a community beyond individual interests were comboned with the Gaecheon-jeol celebration. We can say Gaecheon-jeol was a product of nationalism. But Gaecheon-jeol’s nationalism was different to that of post-modernists. It also had no connection with dictatorship, aggression, chauvinism and totalitarianism.

플랙셔 힌지를 이용한 접합공정 평행도 측정

정영훈(Young Hun Jeong),정승원(Seung Won Jung),윤원수(Won Soo Yun),진송완(Songwan Jin),박철우(Cheol Woo Park) 한국생산제조학회 2011 한국생산제조시스템학회 학술발표대회 논문집 Vol.2011 No.4

In this study a sensor for parallelism measurement for a bonding process was developed. To measure the inclination angle between two planes, four flexures based on leaf spring was introduced to the sensor design and the bending strains of four flexures were used in the estimation of inclination angles which were roll and pitch. Consequently, it was demonstrated that the estimation accuracy of the inclination angles could be improved to be three-times higher than that of prescale pressure film in existing method.

안호상과 일민주의의 단군민족주의

정영훈(Jeong, Young-Hun) 고조선단군학회 2018 고조선단군학 Vol.39 No.-

안호상은 이승만정부에서 초대 문교부장관을 역임한 인물이다. 그는 단군민족주의로부터의 큰 영향속에 학문과 실천운동을 전개한 대표적인 인물이라 할 수 있다. 특히 단군민족주의의 종교방면 전개라 할 수 있는 대종교와의 인연이 중요한데, 그는 청년기에 대종교에 입교하였고 노년기에는 교단의 최고 수장 직도 수행했었다. 이 논문에서는 안호상의 활동노선과 학문연구 및 일민주의 정치이론을 단군민족주의와의 관련속에서 분석하였다. 논문에서 다루고 있는 문제는 다음과 같은 3가지이다. 첫째, 안호상의 활동과 사상을 단군민족주의와의 관련 속에 검토하고자 하였다. 그가 단군민족주의자가 된 과정과 단군민족주의의 실천과 활성화를 위해 힘쓴 내역을 살폈다. 둘째, 안호상의 일민주의를 특히 단군민족주의와 연계속에 살피고자 하였다. 단군민족주의가 발굴한 자료들에 기초하였고 단군민족주의적 민족적 공동운명론을 정책적으로 구체화하였음을 밝혔다. 셋째, 안호상의 단군민족주의를 평가해보고자 하였다. 논문에서는 안호상의 사상과 학문을 전체주의・국가주의・파시즘・유사역사학이라고 매도하기만 하는 것은 부적절하다는 점을 지적하였다. 그가 전개하는 민족적 공동운명체론은, 개인자유주의를 넘어서 공동체적 통합과 행복으로 나아가는 사상적 대안으로서 나름의 의미를 갖는다고 보았다. 중독・왜독・양독의 삼독극복론과 연구성과들 역시 우리의 학술연구 자세에 대해 반성하게 하고 역사와 문화에 대한 상상력을 보강해준다. 그러나 반공 노선과 대한민국 국가를 민족・단군・통일 등과 같은 가치・과제보다 우선시한 것이나, 전쟁 및 좌우대결 과정에 빚어진 민족적 희생과 이승만의 독재권력 강화에 대해 침묵한 것은 단군민족주의의 기본지향에서 이탈한 것이라 할 수 있다. 그리고 위대한 민족사에 대해 과도하게 집착하면서 과학적 엄밀성에서 후퇴한 것 역시 신채호가 정립했던 단군민족주의적 국학정신으로부터 크게 퇴보한 것이라 평가하였다. AhnHoSang was the first minister of the Ministry of Education of Lee Seung-man Government. He was a representative figure who was influenced by Dangun-nationalism in academic and practice movement. He joined Daejonggyo, the religious development of Dangun-nationalism, in his youth and carried out the presidency of Daejonggyo in his last years. Ilminism, AhnHoSang’s political theory was the ideology which was expressed with the socio-political idea of Dangun-nationalism. This paper deals with following 3 problems. (1) What were the relevancies between AhnHoSang and Dangun-nationalism? And how did he endeavor to consolidate the Dangun-nationalism? (2) What correlations were between Ilminism and Dangun-nationalism? And how were the idea of national common destiny embodied in Ilminism? (3) Is it proper to evaluate Ilminism as totalitarianism, statism, fascism and dictatorship? If not why?