• Title/Summary/Keyword: reducing atmosphere

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The Role of Weather and Climate Information as a Growth Engine for Passing the Gross Domestic Product per Head of $20,000 (국민소득 2만달러 달성의 성장엔진으로서 기상정보의 역할)

  • Kim, Yeong-Sin;Lee, Ki-Bong;Kim, Hoe-Cheol
    • Atmosphere
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    • v.15 no.1
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    • pp.27-34
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    • 2005
  • High quality meteorological information is the typical product of service business industry which can offer the investment initiative by reducing the uncertainty and by activating other related industries. It requires a high level of meteorological technology and of ability to transform such technology as merchandising products. According to the analysis of the WMO data, the level of Korean meteorological technology is comparable to that of the nation with $17,500, GDP per head. However, the income of the meteorological business agent earns in Korea is 8 billion 4 hundred million won which is less than a tenth of that made by the US or Japan. The potential for such business field in Korea will be strong enough, if one can overcome such weak points. In addition, the efforts made by the government to advance the meteorological technology have been actualized gradually. Korean government will have a chance that is comparable to offering jobs for 20,000 unemployed by creating incomes of 40 billion won by meteorological technology as a sustained economic growth engine. It is proposed that government stimulate demand and supply by focusing on sales quantity than the price. The key points for creating the new demand are marketing and outsourcing of weather and climate information by maintaining the cooperative relationship between private and public sector.

Eu$^{2+}$ Activated Green Phosphor $Ba_2CaMgSi_2O_8:Eu^{2+}$

  • Kim, Jeong-Seog;Piao, Ji Zhe;Choi, Jin-Ho;Cheon, Chae-Il
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1076-1078
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    • 2004
  • In this paper, we report $Eu^{2+}$ activated green phosphor $Ba_2CaMgSi_2O_8:Eu^{2+}$. This phosphor absorbs ultroviolet radation and emits a green visible light. The phosphors were synthesized by conventional solid state reaction method. Reagent grade $BaCO_3$, $CaCO_3$, MgO, $SiO_2$, $Eu_2O_3$ were used as raw materials. The raw materials were mixed thoroughly with an appropriate amount of ethanol in an agate mortar and then dried at 90 $^{\circ}C$ for 2 hours. The mixture was sintered at 900 $^{\circ}C$ for 2 hours and reheated at the mild reducing atmosphere 5% $H_2$ gas mixed with 95% $N_2$ gas at about 900 $^{\circ}C$ to 1250 $^{\circ}C$ for 2 hours. The photoluminescence spectra of the phosphor powders were measured by a fluorescent spectrophotometer. The crystal structure of phosphor powders were investigated by X-ray diffractometer.

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Effect of Natural Antioxidant and Packaging Material on the Oxidative Stability of Waffle (천연 항산화제와 포장재질이 Waffle의 산화 안정성에 미치는 영향)

  • 신언환;한규홍
    • Culinary science and hospitality research
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    • v.9 no.4
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    • pp.1-12
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    • 2003
  • This study was conducted to evaluating the antioxidative activities of waffle by natural antioxidants combination (tocopherol, rosemary extract and tea polyphenol) and packaging. Waffle stored at $25^{\circ}C$ and 35$^{\circ}C$ for 70 days were evaluated for acid value, peroxide value and Q$_{10}$ value. Tocopherol, either alone or with rosemary and tea polyphenol, was highly effective in inhibiting lipid oxidation of waffle at $25^{\circ}C$ and 35$^{\circ}C$. Especially among them, rosemary extract exhibited the best synergistic effect, as determined by peroxide value measurement. Waffle was then packaged under the following packing materials (OPP/DL/VMCPP, PET/DL/VMCCP). As the temperature condition, the modified atmosphere decrease in waffle package and increase peroxide value. This result indicated that the PET package was more effective in reducing oxidation than the OPP package.

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Dielectric Properties of Non-reducible X7R Dielectric Materials in $BaTiO_3$-$Er_2$$O_3$--MgO ($BaTiO_3$-$Er_2$$O_3$-MgO 첨가계를 이용한 내환원성 X7R 재질의 유전특성에 관한 연구)

  • 한영호;최상근;황진현
    • Journal of the Korean Ceramic Society
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    • v.38 no.7
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    • pp.615-620
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    • 2001
  • E $r_2$ $O_3$-MgO 복합 첨가가 BaTi $O_3$계 내환원성 X7R 재질의 유전특성에 미치는 영향에 대하여 환원성 분위기에서 연구하였다. (B $a_{1-x}$ E $r_{x}$)( $Ti_{1-y}$M $g_{y}$ ) $O_3$첨가계에서 1.0 mol% 이상 MgO의 복합첨가로 E $r_{Ba}$ 도너 불순물과 $Mg_{Ti}$ 억셉터 불순물이 전기적으로 보상되어, 환원성분위기 소결 후에도 $10^{10}$Ωcm 이상의 높은 절연저항을 나타내었다. E $r_2$ $O_3$가 첨가된 시편에서 MgO가 2.0 mol% 이상 첨가될 경우, 유전율의 온도안정성이 향상되어 X7R 규격을 만족시켰으며 1.0$mu extrm{m}$ 이하의 작고 균일한 입자가 관찰되었다. 한편, E $r_2$ $O_3$의 첨가량이 3.0 mol%로 증가함에 따라 유전율의 온도안정성이 향상되었으나 상대적으로 상온 유전상수값이 현저히 감소하였다.였다.다.

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Thermal Decomposition of $\beta$$-Sialon by Graphite (이연에 의한 $\beta$$-사이알론의 열분해)

  • 최상흘;이희철;이종진;서규식
    • Journal of the Korean Ceramic Society
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    • v.24 no.5
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    • pp.453-460
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    • 1987
  • β'-sialon(Z=2.7) specimens with <30%wt. graphite as a reducing agent were decomposed at 1350°up to 1,450℃ under the atmosphere of 90% N2-10%H2. The decomposition of β'-sialon was calculated from the change in Z-value, and the formation of new minerals was identified from X-ray diffraction patterns. The decomposition reactions of sialon were considered to yield a stable sialon close to β-silicon nitride and some aluminum compounds according to the following equations; β'-sialon(s)+C(s)+N2(g)→β2-sialon(metastable)+β3-sialon(stalbe phase) β2-sialon(s)+C(s)+N2(g)→β3-sialon(s)+AlN(s)+α-Al2O3(s)+15R(s)+SiO(g)+Al2O(g)+CO(g) Z-value; β2( 3.5)>β'( 2.7)>β3( 0.5) The decomposition rate of sialon was controlled by two mechanisms ; One was characterized by the interface area of contact, corresponding to an apparent activation energy of 50.5Kcal/mol in the initial stage, and the other by the diffusion, corresponding to that of 104.3Kcal/mol in the final stage of the decomposition.

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On the Study Of AlSiCa($Al_2O_3-SiC-C$) refractories: (I) Synthesis of raw material using domestic chnmotte (AlSiCa($Al_2O_3-SiC-C$)계 내화물 재료에 관한 연구: (I) 국산 chamotte로부터 원료분말합성)

  • Shim, Kwang-Bo;Joo, Kyoung;Auh, Keun-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.4
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    • pp.626-631
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    • 1997
  • AlSiCa powders were prepared from the domestic Hadong Kaolin ($Al_2O_3{\cdot}2SiO_2{\cdot}2H_2O$). As a result of the reaction of Hadong Kaolin and carbon powder at reducing atmosphere, $Al_2O_3{\cdot}SiC$ composite started to form at $1300^{\circ}C$ and completed at $1400^{\circ}C$. The optimum amount of carbon was 1:4 in mole ratio. It was found that only bright-green $\beta-SiC$ phase forms when the mixture was packed without carbon powder in alumina crucible.

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A Study on Standby Power and Reduced Power Consumption Control System for High-efficiency Module (대기전력 및 소비전력 절감을 위한 고효율 모듈제어 시스템에 관한 연구)

  • Lee, Myung-Hwan;Park, Yung-Teak;Chung, Hun-Suk;Kang, Ey-Goo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.5
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    • pp.334-339
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    • 2012
  • A study on electrical and electronic equipment will occur in the atmosphere, which is essential to cut the power to prevent the waste of power by power measurement technology development and to develop the technology to do this operation is the main core of standby power to detect and block it and return the configured for software and hardware, while the actual construction to ensure stability through field testing and debugging of problems improved accordingly, as well as ease of installation and so it could be done while the test. In addition, in terms of basic hardware switching of standby power when blocking, reducing stress and ensure stable operation and circuit design, power off and back to ensure stable operation even when a protection circuit is applied.

An Analysis of Factors Affecting Job Stress and Job Satisfaction of the Physical Therapists in Korea (물리치료사의 스트레스와 직무만족도에 영향을 미치는 요인분석)

  • Lee, Ji-Hyun;Sohn, Ae-Ree
    • Journal of Korean Physical Therapy Science
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    • v.10 no.2
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    • pp.153-162
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    • 2003
  • The purpose of this study was to examine the working condition of physical therapists and the degree of job satisfaction. This study also was to identify the causes of job stress: to examine job stress and job satisfaction; and to find factors that affect job satisfaction for physical therapists in Korea. A self-administered questionnaire survey was conducted from February 17 to March 15 in 2003. Survey data was obtained from 255 therapists registered in Korean Physical-Therapists Association. Results were as follows: 1. The degree of job satisfaction was moderate. 2. The degree of stress with their work was a little high. 3. Duty itself is one of the main factors of job stress of physical therapists. Working atmosphere and the relationships with job colleagues turned to be closely related to the degree of satisfaction. 4. The longer their total term of service was and the older they are, the greater the satisfaction with work was. In conclusion, the physical therapists can be encouraged to do their work more energetically and voluntarily. At the same time, the feeling of mission can also grow by shortening of working hours, reducing the quantity of work, and offering more salary. It is also to recommend an effective performance of duty and the development of their medical service to be introduced.

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An Experimental Study to Determine Proper Lighting Conditions in Powder Rooms

  • Kim, Hyun-Ji;Lim, Jang-Hyeon;Kim, Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.12
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    • pp.54-62
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    • 2013
  • In this study, a mock powder room was installed with variable LED lighting environments in order to conduct the experiments. The experimental conditions include luminaire type, illuminance ratio, vertical illuminance and color temperatures. The evaluation methods used were the Semantic Differential Method and a subjective evaluation on activities through observation. The SD evaluation result factor analysis categorizes ideas into three factors: brightness, emotion, and glare. The vertical bracket or the combined luminaire (luminous panel+ Vertical bracket) has better brightness than luminous panel. A vertical illuminance of 500lx is not significantly difference as compared to 600lx, allowing 500lx to be considered standard. The emotional atmosphere is evaluated as being better at lower color temperature. The luminous panel is the best for reducing glare while the vertical bracket is the worst. The best conditions differ according to the illuminance ratio of the luminous panel and vertical bracket. In the subjective evaluation (satisfaction with lighting environment, suitability to activity) the combined luminaire and 4000K received the best evaluation.

Intercomparison of interannual changes in NDVI from PAL and GIMMS in relation to evapotranspiration over northern Asia

  • Suzuki Rikie;Masuda Kooiti;Dye Dennis
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.162-165
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    • 2004
  • The authors' previous study found an interannual covariability between actual evapotranspiration (ET) and the Normalized Difference Vegetation Index (NDVI) over northern Asia. This result suggested that vegetation controls interannual variation in ET. In this prior study, NDVI data from the Pathfinder AVHRR Land (PAL) dataset were analyzed. However, studies of NDVI interannual change are subject to uncertainty, because NDVI data often contain errors associated with sensor- and atmosphere-related effects. This study is aimed toward reducing this uncertainty by employing NDVI dataset, from the Global Inventory Monitoring and Modeling Studies (GIMMS) group, in addition to PAL. The analysis was carried out for the northern Asia region from 1982 to 2000. 19-year interannual change in PAL-NDVI and GIMMS-NDVI were both compared with interannual change in model-assimilated ET. Although the correlation coefficient between GIMMS-NDVI and ET is slightly less than for PAL-NDVI and ET, for both NDVI datasets the annual maximum correlation with ET occurs in June, which is near the central period of the growing season. A significant positive correlation between GIMMS-NDVI and ET was observed over most of the vegetated land area in June as well as PAL-NDVI and ET. These results reinforce the authors' prior research that indicates the control of interannual change in ET is dominated by interannual change in vegetation activity.

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