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Measurement of electron temperature and density using Stark broadening of the coaxial focused plasma for extreme ultraviolet (EUV) lithography

  • Lee, Sung-Hee;Hong, Young-June;Choi, Eun-Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.475-475
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    • 2010
  • We have generated Ar plasma in dense plasma focus device with coaxial electrodes for extreme ultraviolet (EUV) lithography and investigated an emitted visible light for electro-optical plasma diagnostics. We have applied an input voltage 4.5 kV to the capacitor bank of 1.53 uF and the diode chamber has been filled with Ar gas of pressure 8 mTorr. The inner surface of the cylindrical cathode has been attatched by an acetal insulator. Also, the anode made of tin metal. If we assumed that the focused plasma regions satisfy the local thermodynamic equilibrium (LTE) conditions, the electron temperature and density of the coaxial plasma focus could be obtained by Stark broadening of optical emission spectroscopy (OES). The Lorentzian profile for emission lines of Ar I of 426.629 nm and Ar II of 487.99 nm were measured with a visible monochromator. And the electron density has been estimated by FWHM (Full Width Half Maximum) of its profile. To find the exact value of FWHM, we observed the instrument line broadening of the monochromator with a Hg-Ar reference lamp. The electron temperature has been calculated using the two relative electron density ratios of the Stark profiles. In case of electron density, it has been observed by the Stark broadening method. This experiment result shows the temporal behavior of the electron temperature and density characteristics for the focused plasma. The EUV emission signal whose wavelength is about 6 ~ 16 nm has been detected by using a photo-detector (AXUV-100 Zr/C, IRD). The result compared the electron temperature and density with the temporal EUV signal. The electron density and temperature were observed to be $10^{16}\;cm^{-3}$ and 20 ~ 30 eV, respectively.

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A Cross-Sectional Study on ${\gamma}-GTP$ and its Related Factors in Male Workers (일부 남성근로자에서 ${\gamma}-GTP$와 관련된 요인에 대한 단면연구)

  • Kim, Keon-Yeop;Lee, Jong-Hyun;Ha, Young-Ae;Lee, Kyung-Eun;Kam, Sin
    • Journal of Preventive Medicine and Public Health
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    • v.35 no.2
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    • pp.169-174
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    • 2002
  • Objective : To investigate gamma-Glutamyltransferase (${\gamma}-GTP$) and its related factors in male industrial workers. Method : Five hundred and tony male workers without heart disease, diabetes mellitus, renal disease, hepatitis, and other liver diseases were surveyed in October 1998. Blood samples were collected to test for ${\gamma}-GTP$, total-cholesterol and fasting blood glucose. A self-administered questionnaire survey on life style was also done. Results : The total geometric mean value of ${\gamma}-GTP$ was 30.6 U/L. According to a univariate analysis: age, BMI(body mass index, $kg/m^2$), alcohol consumption, current smoking, stress, diastolic blood pressure, and blood total cholesterol were significantly associated with ${\gamma}-GTP$(p<0.05). From a multiple regression analysis: BMI, alcohol consumption, current smoking, diastolic blood pressure and total-cholesterol were significantly related to ${\gamma}-GTP$(p<0.05). Coffee consumption was negatively related to ${\gamma}-GTP$, but not significantly. Conclusion : We recommend that a change in health behavior (i.e. reducing alcohol intake, controlling BMI and not smoking) is necessary to decrease ${\gamma}-GTP$ in male workers.

An Analysis of Books Selected in 10 Years of 'The Big Read' Reading Initiative ('The Big Read' 독서 이니셔티브 10년과 선정 책의 분석)

  • Yoon, Cheong-Ok
    • Journal of the Korean Society for Library and Information Science
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    • v.52 no.1
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    • pp.159-178
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    • 2018
  • The purpose of this study is to understand the characteristics of books selected for 'The Big Read' community reading initiative of the National Endowment for the Arts from 2006 to 2017 and its relation with 'One Book, One City' community reading campaign in the U.S.A. An analysis of 1,407 TBR programs and 745 participating communities, and 56 books from TBR Library shows that TBR expands and complements 'One Book' reading campaigns, and confirms the sustenance of this innovative model. TBR Libray books were selected with TBR's own criteria, but their features are generally very similar to those of 1,102 books selected for 'One Book' programs. They often reflect some interests in such universal values as coming of age, justice, integrity, etc. and diverse cultural experiences and life. The outcomes of 'One Book' and TBR cannot be qualitatively measured, but their sustainable value of communication through one selected book has been well proved.

An Overturn disease of Cultured Mud Loach (Misgurnus mizolepis) (미꾸라지 (Misgurnus mizolepis)의 뒤집힘병에 관한 연구)

  • Park, Seong-U;Park, Hyeon-Tae;Choe, Seon-Nam
    • Journal of fish pathology
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    • v.17 no.1
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    • pp.21-28
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    • 2004
  • In late summer of 2001, a new disease "overturn disease" occurred among mud loach (Misgurnus mizolepis) cultured in a farm Chonbuk Province. The fish exhibited a lethargic, erratic and spiral swimming at the water surface. Affected fish showed swollen abdomen with accumulation of air bubbles in the intestinal canal. The bubbles were much larger in the anterior part than in the posterior part. Hematological and histopathological examinations were done. No significant differences were found in RBC count, Ht value and Hb concentration between the diseased and the healthy fish. Gill filaments showed proximal hyperplasia of the respiratory epithelia and fusing of the gill lamella. Hemorrhage and necrosis occurred in the intestinal epithelia and within the lamina propria, and the mucosal epithelia were separated from the muscularis. Hepatocytes underwent atrophy. In the fish experimentally tied between the annal fin and the anus by a thread to confirm accumulation of air bubbles within intestine, accumulation of air bubbles was confirmed. This disease in mud loach appeared to be induced by circulatory disturbances in the intestinal wall owing to accumulation of air bubbles in the alimentary canal after fed high protein diet throughout all culturing period.

A Study on the 1970's Korean Psychedelic Rock (focusing on Shin, Joong-hyun) (1970년대 한국의 사이키델릭 록에 관한 연구 -신중현의 작품을 중심으로-)

  • Ham, Chun-Ho;Cho, Tae-Seon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.694-699
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    • 2016
  • The study of popular music in Korea has been looked down on in terms of its academic value, which has led to the demise of research into this topic. Unlike classical music, all areas of study of pop music (history, theory, and performance) in Korea inevitably rely on curriculums and courses in foreign countries. This study focuses on the era of the Eighth U.S. Army when modern band music first arose in Korea to discuss the important role played by Shin Joong Hyun's Psychedelic music style. Shin Joong Hyun's new approach to arranging and harmonizing included the qualities of Western music, but kept the melody lines of our own traditional style. Shin Joong Hyun's music is still being played by today's musicians decades later and it definitely deserves to be praised for generations to come. Although this study only covers a limited portion of our pop music history, its purpose is to provide future generations of musicians with knowledge on the roots of our pop music culture.

A Study on the Photoisomerization of Monolayer Film of Long Chain Fatty Acids Containing Azobenzene (아조벤젠을 함유한 장쇄 지방산 단분자 막의 광이성화 현상에 관한 연구)

  • Kim, Moo-Goon;Park, Tae-Gone;Park, Keun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.13 no.1
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    • pp.75-85
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    • 1996
  • The absorption spectra of synthesis of long chain fatty acid containing azobenzene start from p-(p'-hydroxy phenyl azo)-benzoic acid was investigated by ultraviolet spectrophotometery in chloroform solvent at the various temperature. In addition, The pressure-area of the water-air interface was obtained and the LB film was fabricated onto a quartz slide and quartz crystal by conventional Langmuir-Blodgett(LB) method. The UV absorption spectra of Langmuir-Blodgett(LB) film on quartz slide and spectrum of monolayer formed on quartz crystal have been measured. Long chain fatty acid containing azobenzene are induced phtoisomerization by the application of u. v. and visible light irradiation alternatively the reversibility of phtoisomerization was more clear difference when the number of $C_{n}$ increased but, not so good at $C_{14}-azo$. At the pressure-area isotherms, the value of surface pressure increment were decreased when the number of $C_{n}$ increased. A surface pressure of 20mN/m was obtained as a proper one for a film deposition. The photoisomerization at LB films were induced by application of UV and visible light irradiation alternatively. So the LB film of long chain fatty acid containing azobenzene has possibility to being applied to functional molecular devices such as photomemory and light switching.

Preparation, Structural and Magnetic Properties of Ordered Perovskite (BaLa)(MgMo)O$_6$

  • Choy Jin-Ho;Hong Seung-Tae
    • Bulletin of the Korean Chemical Society
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    • v.10 no.1
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    • pp.8-12
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    • 1989
  • The polycrystalline powder of (BaLa)(MgMo)$O_6$ has been prepared at $1350^{\circ}C$ in a nitrogen flowing atmosphere. The powder X-ray diffraction pattern indicates that (BaLa)(MgMo)$O_6$ has a cubic perovskite structure ($a_0$ = 8.019(3) $\AA)$ with 1:1 ordering or $Mg^{2+}$ and $Mo^{5+}$ in the oxide lattice. The infrared spectrum shows two strong absorption bands with their maxima at 600(${\nu}3$) and 365(${\nu}4$) cm-1, which are attributed to $2T_{1U}$, modes of molybdenum octahedra MoO6 in the crystal lattice. According to the magnetic susceptibility measurement, the compound shows a paramagnetic behavior which follows the Curie-Weiss law below room temperature with the effective magnetic moment 1.60(1){$\mu}B$, which is consistent with that of spin only value ($1.73{\mu}B$) for $Mo^{5+}$ ($4d^1$ electronic configuration). From the thermogravimetric and X-ray diffraction analyses, it has been found that (BaLa)(MgMo)$O_6$ decomposes gradually into $BaMoO_4$, $MoO_3$ and unidentified phases above $900^{\circ}C$ in an ambient atmosphere, absorbing about 0.25 mole $O_2$ per mole of Mo ion, which also supports that oxidation state of $Mo^{5+}$ in the (BaLa)(MgMo)$O_6$.

Acute Hydrogen Cyanide Poisoning in a Plating Worker and Workplace Measurement (도금 사업장 근로자에게 발생한 시안화수소 급성중독과 작업환경평가)

  • Ham, Seunghon;Choi, Won-Jun;Lee, Junhyung;Lim, Yong su;Kang, Jihyun;Kang, Seong-Kyu
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.29 no.3
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    • pp.336-342
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    • 2019
  • Introduction: An unexpected death was reported in a beginner immediately after starting the work at a plating factory. After the incident, air sampling was performed using a simulation of the situation as it had been at the time. Methods: To evaluate the airborne concentration of hydrogen cyanide, a total of six samples were collected: one personal sample, three area samples, and two background samples (office and outdoors). Hydrogen cyanide measurement was performed according to the standard sampling protocol recommended by the U.S. NIOSH (National Institute of Occupational Safety and Health). Results: The highest concentration of hydrogen cyanide was 0.938 ppm measured in a sample collected from the plating bath area with local exhaust ventilation. This value was approximately 20% of the ceiling occupational exposure limit. The personal sample showed a concentration of 0.135 ppm. Samples collected near the bath in which the incident occurred and a dehydrator showed hydrogen cyanide concentrations of 0.236 ppm and 0.101 ppm, respectively. Hydrogen cyanide was not detected in the background samples (office and outdoors). Conclusions: It is necessary to use proper ventilation systems and respirators in plating factories to prevent acute poisoning. Furthermore, it is important to educate and train new workers dealing with toxic substances.

Thermal Performance Assessment of Insulated door by experiment. (실측 실험을 통한 단열문의 열성능 평가)

  • Jang, Cheol-Yong;Kim, Chi-Hoon;Ahn, Byung-Lip;Hong, Won-Hwa
    • Journal of the Korean Solar Energy Society
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    • v.31 no.2
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    • pp.47-52
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    • 2011
  • Currently, Exterior wall's U-value about building envelope is 0.36 W/$m^2K$(Central Region), but window's one is 2.1 W/$m^2K$ according to air gap of glazing, filling gas, coating and type of windows. The door"s one is 1.6~5.5 W/$m^2{\cdot}K$ depending on material and configuration of door. As such, energy loss per unit of door is considerably larger like windows. The door for the recognition was relatively low because energy loss through the door is relatively small compared to window area. In this paper, thermal performance was analyzed through simulation targeting the door which has thermal break that can improve the insulation performance and doesn't have one. As a results of simulations, case1 was calculated as the average of 1.63 w/m2k and case 2 was calculated as the average of 4.14 w/m2k. The thermal performance of door depends on the type and condition of insulations. As a results of final simulations, Case1 was calculated as 1.06 w/m2k and Case2 was calculated as 1.27 w/m2k. As a results of the experiments, thermal performance of case 1 was measured as 1.28 w/m2k. Error between experiments and simulations is considered problems encountered when creating the samples. The effect of door frame on the overall thermal performance is slight because it's a small proportion of the door frame.

Issues on Particular Market Situation to Calculate Dumping Margin of Korean Steel Products by the USA

  • Wang, Jingjing;Choi, Chang Hwan
    • Journal of Korea Trade
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    • v.25 no.1
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    • pp.89-111
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    • 2021
  • Purpose - The U.S. Trade Preference Expansion Act (TPEA) of 2015 enables the US Department of Commerce (DOC) to inflate dumping margin when the particular market situation (PMS) exists in the exporter's home market. DOC applied PMS provisions to the steel products from Korea. This paper analyzes whether DOC's calculation by using the regression analysis is consistent with WTO rules. Design/methodology - This paper analyzes the PMS application in law and regression analysis that extends the data period from 10 years to 18 years using the same economic model with DOC, and changes the country group according to the quantities of steelmaking capacity. Findings - Results show that DOC's argument conflating the sales-based with cost-based PMS designed to inflate dumping margins might not be consistent with WTO Antidumping Agreement Article 2.2 and 2.2.1.1 in which costs shall normally be calculated on the basis of records kept by the exporter, providing generally accepted accounting principles and reasonably reflection of the costs and PMS that exists in the Korean steel product markets. Even if it will be consistent, DOC's calculated margin by the regression analysis using a 10-year data is a big gap (5 times) compared with an 18-year data projection and different countries' data through the same methodology, which is a huge gap of regression coefficient. It means that dumping margin would be very wide range from 7.8% to 38.54% and unstable to calculate. Inflating dumping margin by DOC using regression analysis would not only be inconsistent with WTO rules, but also projection result is unreliable. Originality/value - Literature papers have mainly analyzed WTO law itself. This paper however, would be the first attempt to analyze the DOC's new way of dumping margin calculation in both manners of law and an empirical methodology perspective at the same time.