• 제목/요약/키워드: U-Value

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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
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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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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일부 남성근로자에서 ${\gamma}-GTP$와 관련된 요인에 대한 단면연구 (A Cross-Sectional Study on ${\gamma}-GTP$ and its Related Factors in Male Workers)

  • 김건엽;이종현;하영애;이경은;감신
    • Journal of Preventive Medicine and Public Health
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    • 제35권2호
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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.

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

  • 윤정옥
    • 한국문헌정보학회지
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    • 제52권1호
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    • pp.159-178
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    • 2018
  • 이 연구의 목적은 2006년부터 2017년까지 진행된 미국 National Endowment for the Arts가 지원하는 'The Big Read(TBR)' 지역사회 독서운동에서 선정된 책들의 특성 및 'One Book'과의 관계를 살펴보는 것이다. 2017년 12월 현재 NEA의 TBR에 참여한 1,407개 프로그램과 745개 지역사회, TBR Library 선정 책 56권을 분석한 결과는 TBR은 'One Book' 독서운동을 확장 및 보완하고 있으며, 이 독서운동 모형의 지속가능성을 확증하였다. TBR은 책 선정에서 독자적 지향점을 갖지만, 주제적 특성은 'One Book' 책 1,102권의 축소판과 같은 유사성을 가진다. 성장, 정의, 관용과 같은 인간의 보편적 가치 및 미국 내 다양한 민족과 문화 경험과 삶에 대한 관심을 반영한다. 'One Book'과 TBR의 가시적 성과는 계량하기 어려우나, 한 권의 책을 통한 소통의 가치는 지속가능함을 확인하였다.

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

  • 박성우;박현태;최선남
    • 한국어병학회지
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    • 제17권1호
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    • pp.21-28
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    • 2004
  • 양식 미꾸라지 (Misgurnus mizolepis)가 수중으로 잠입하지 못하고 양어지의 물표면에 배를 위로 한 채 힘없이 회전 유영을 하는 질병이 발생하였다. 병어는 복부가 팽만되어 있었으며, 해부하여 보면 소화관에 커다란 공기방울의 축적, 장염이 현저하였다. 병어를 혈액학적으로 조사한 결과 적혈구수, Ht치 및 Hb 농도는 건강어와 차이가 없었다. 병리조직학적으로는 아가미의 호흡상피의 증생과 새변의 유착, 소화관 상피세포의 출혈, 괴사 및 박리가 관찰되었다. 뒷지느러미와 항문사이를 실로 결박하여 항문으로부터 공기의 배출을 억제한 재현 실험에서 발병어와 같은 증상이 재현되었다. 따라서 이 병은 빠른 성장을 목적으로 고단백질 사료를 투여함으로서 장호흡을 위하여 마신 공기가 소화관내에 축적되고, 축적된 공기의 부력 때문에 물속으로 하강하지 못하게 되고, 또 소화관을 압박하여 소화관에 순환장애를 일으킨 결과 폐사한 것으로 추정된다.

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

  • 함춘호;조태선
    • 한국산학기술학회논문지
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    • 제17권9호
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    • pp.694-699
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    • 2016
  • 대중음악은 천한 것으로 여겨져 학술적인 가치를 인정받지 못하였고 이와 관련한 연구는 상당히 미흡한 실정이다. 따라서 지금의 음악교육은 전통음악을 제외하고 나면, 역사, 이론, 실연에 관한 모든 분야가 외국의 사례를 통해야만 하는 상황이다. 다소 늦은 감이 있지만 비로소 이 분야에 관한 연구의 필요성을 절감했다. 우선 비교적 가까운 역사인 미 8군으로 부터 시작된 밴드 음악에 초점을 맞추고, 그 중심에서 가장 큰 활약을 했던 신중현의 사이키델릭 음악을 시작점으로 하였다. 신중현의 편곡 기법이나 화성을 사용하는 방식은 미국의 것을 가져왔으나 선율 자체는 우리의 색깔을 지니고 있다. 그의 음악은 그 당시는 물론 시대를 뛰어넘어 후배 음악가들에 의해 계속 연주되고 있다는 점에서 높이 평가 받아야 마땅하다. 비록 일부분에 한정되어 있지만 본 연구는 우리 대중음악 역사의 한 장면을 되짚어보고 이에 관한 자료들을 남겨서 후배들에게 우리 대중음악의 뿌리를 조금이나마 알리고자 한다.

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

  • 김무군;박태곤;박근호
    • 한국응용과학기술학회지
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    • 제13권1호
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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$_6$

  • 조진호;홍성태
    • Bulletin of the Korean Chemical Society
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    • 제10권1호
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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)$O_6$.

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

  • 함승헌;최원준;이준형;임용수;강지현;강성규
    • 한국산업보건학회지
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    • 제29권3호
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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.

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

  • 장철용;김치훈;안병립;홍원화
    • 한국태양에너지학회 논문집
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    • 제31권2호
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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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    • 제25권1호
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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.