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Character Analysis of Micro Fuse Fusing as a function of De-Rating technique (디레이팅 기법에 의한 마이크로 퓨즈 용단의 특성 분석)

  • Kim, Do-Kyeong;Kim, Jong-Sick
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.6
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    • pp.8-13
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    • 2015
  • Recently, Illumination industry of LED module has been focused to industry technology for energy conservation of nation. The LED device is excellent to power efficiency due to semiconductor light source element. And the application to the lighting circuit technology can be designed to the sensitive lighting system for human sensitivity control. In this paper, as a process for analyzing the operating temperature of standardized electronic device including LED device has analyzed about fusing character with in designed micro fuse for electronic device protection from the over current. Using the de-rating technique, which is performed to micro fuse fusing test in the range of $-30^{\circ}C{\sim}120^{\circ}C$ thermostatic chamber. To the output data in each temperature zone, it is performed to first-order linear fitting. Additionally, applying the resistance temperature coefficient and statistical data for the reliable analysis has derived to the metal element resistance of micro fuse with temperature change of the thermostatic chamber. As a research result, The changed temperature effect of thermostatic chamber was confirmed regarding fusing time change.

Control of Glass Infiltration at the Al2O3/Glass/Al2O3 Interface

  • Jo, Tae-Jin;Yeo, Dong-Hun;Shin, Hyo-Soon;Hong, Youn-Woo;Cho, Yong-Soo
    • Transactions on Electrical and Electronic Materials
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    • v.12 no.1
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    • pp.32-34
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    • 2011
  • A zero-shrinkage sintering process in which the shrinkage of the x-y axis is controlled to be zero is in great demand due to the high integration trend in ceramic modules. Among the zero-shrinkage sintering processes available, the glass infiltration method proposed in the preliminary study with an $Al_2O_3/Glass/Al_2O_3$ structure is one promising method. However, problems exist in regard to the glass infiltration method, including partially incomplete joining between $Al_2O_3$ and glass layers due to the precipitate of Ti-Pb rich phase during the sintering process. Therefore, we wish to solve the de-lamination problems and suggest a mechanism for delamination and the solutions in the zero-shrinkage low temperature co-fired ceramic (LTCC) layers. The de-lamination problems diminished using the Pb-BSi-O glass without $TiO_2$ in Pb-B-Ti-Si-O glass and produced a very dense zero-shrinkage LTCC.

Suitability Assessment of Domestic Natural Waters as a Culture Medium for Daphnia magna (Daphnia magna의 배양배지로서 국내 자연수의 적절성 평가)

  • Yeom, Dong-Hyuk;Jeon, Chan-Sig
    • Korean Journal of Ecology and Environment
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    • v.45 no.3
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    • pp.271-277
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    • 2012
  • The present study was conducted to assess the suitability of domestic natural waters as a Daphnia magna culture medium. In order to assess survival rate and reproductive output, young female daphnids (parent animals), aged less than 24 hours at the start of the test and produced in the Elendt M4 medium, were exposed to Elendt M4 medium, de-chlorinated tap water, and natural mineral water for 21 days. D. magna cultured in Elendt M4 medium (reference medium) and natural mineral water met the criteria of OECD No. 211, Daphnia magna Reproduction Test Guidelines in terms of percent adult survival, first day of reproduction, and average young production. However, the mortalities of adult daphnids observed in de-chlorinated tap water were more than 20% in two reproduction tests for 21 days. Mortality was observed on exposure days 13, 15, and 18 in de-chlorinated water. The use of D. magna is recommended in water of hardness >80 mg $CaCO_3\;L^{-1}$. However, the hardness of de-chlorinated tap water used in the present study was 50~53 mg $CaCO_3\;L^{-1}$. Therefore, it is judged that the delayed mortalities observed in de-chlorinated tap water were caused by a rapid decreased in hardness when the medium was changed from Elendt M4 to de-chlorinated tap water. When D. magna is cultured using domestic natural waters (underground water, surface water, and de-chlorinated water), the quality-control (QC) data should be maintained through a standardization for health assessment method, toxicity test method using reference chemical, test intervals of reference toxicant toxicity test, and data treatment and interpretation. In the long term, national research programs are needed for the development of test species which are representative of domestic aquatic environmental conditions among indigenous daphnids.

Increase of $CoQ_{10}$ Production Level by the Coexpression of Decaprenyl Diphosphate Synthase and 1-Deoxy-D-xylulose 5-Phosphate Synthase Isolated from Rhizobium radiobacter ATCC 4718 in Recombinant Escherichia coli

  • Seo, Myung-Ji;Im, Eun-Mi;Nam, Jung-Yeon;Kim, Soon-Ok
    • Journal of Microbiology and Biotechnology
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    • v.17 no.6
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    • pp.1045-1048
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    • 2007
  • Two genes, dps encoding decaprenyl diphosphate synthase and dxs encoding 1-deoxy-D-xylulose 5-phosphate synthase, were isolated from Rhizobium radiobacter ATCC 4718. DNA sequencing analysis of the dps and dxs genes revealed an open reading frame of 1,077 bp and 1,920 bp, respectively. The heterologous expression in Escherichia coli BL21(DE3) was carried out in order to identify their functions. Recombinant E. coli BL21(DE3) harboring the dps gene produced $CoQ_{10}$ as well as $CoQ_8$ and $CoQ_9$, whereas E. coli harboring only the dxs gene produced more $CoQ_8$ compared with the wild-type E. coli. Additionally, the coexpression of dps and dxs genes in E. coli was carried out. The recombinant E. coli harboring only the dps gene produced $0.21{\pm}0.04\;mg/l$ of $CoQ_{10}$, whereas the coexpressed E. coli with dps and dxs genes produced $0.37{\pm}0.07\;mg/l$ of $CoQ_{10}$. HPLC analysis also showed that the $CoQ_{10}$ fraction (100% of the total CoQs distribution) was increased from $15.86{\pm}0.66%$ (only dps) to $29.78{\pm}1.80%$ (dps and dxs).

Effect of Graded Levels of Tallow in the Diet on Performance, Digestibility of Fat, Lipogenesis and Body Lipid Deposition of the Weaned Piglet

  • Reis de Souza, T.C.;Aumaitre, A.;Mourot, J.;Peiniau, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.4
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    • pp.497-505
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    • 2000
  • Thirty piglets weaned at 24.5 d of age ($6.9{\pm}0.5kg$) randomly alloted to 3 treatments were used to investigate the effect of dietary tallow on average performance, digestibility of nutrients, metabolic utilization of energy and body composition at 25 kg. Weaned piglets respond to increasing levels of dietary tallow from 0 to 4% and 8% by digestive and metabolic adaptation. Apparent fecal digestibility of fat (AFDf) was highly correlated with the level of dietary tallow (X as % of fat extracted after HCl hydrolysis) by the following curvilinear equation of regression: $AFDf=33.8+6.9X-0.3X^2$. Feed intake expressed as DE was only significantly increased at the higher inclusion level of tallow. But neither average daily gain, nor feed conversion was affected by the addition of fat. On the other hand, body composition at 25 kg was equally affected, by both levels of supplementary fat; dry matter and energy content in the body were significantly higher (p<0.01) in piglets receiving tallow. As a consequence, the energy cost of the live weight gain was also increased from 23 to 24.7 MJ DE/kg (p<0.02) and the efficiency of energy deposition was decreased from 3.2 to 2.8 MJ DE/MJ deposited energy (p<0.01) in the presence of dietary tallow. An increase in the level of fat stimulated the activity of pancreatic lipase up to a constant value of $22{\pm}1.4IU/mg$ protein but conversely depressed the activity of amylase from 300 to 100 IU/mg of protein. The activity of liver acetyl CoA carboxylase and malic enzyme in the perirenal fat were low lind not affected by dietary fat; the activity of glucose-6-phosphate dehydrogenase was high. Opposite to that, the activity of acetyl CoA carboxylase and malic enzyme in the perirenal and backfat were higher than in the liver and both were significantly reduced by the inclusion of fat in the diet. A direct deposition of dietary fat has been demonstrated by increasing the energy and lipid content of the empty body weight gain between 7 and 25 kg of live weight, and decreasing the efficiency of digestible energy utilization.

Une approche sur l' espace $anthropom\'{e}trique$ et l' espace $kinesth\'{e}sique$ (공간해석에 대한 인체지각론적 접근)

  • Lee Bong-Soon
    • Journal of Science of Art and Design
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    • v.3
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    • pp.33-61
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    • 2001
  • Dans les arts modernes, nous ressentons souvent un $probl\`{e}me$ $disloqu\'{e}par$ rapport aux humains. Ceci ne viendrait-il pas $peut-\^{e}tre$ do notre $pens\'{e}e$ dans l' $\'{e}change$ culturelle entre le monde et nous qui s' appuie trop une $temporalit\'{e}$ et logique? Cette $the\`{s}e$ approche ce $probl\`{e}me$ $\`{a}$ travers one perception anthropologique do monde, en $\'{e}tudiant$ les arts tridimensionnels avec ses $\'{e}schelles$ qui deviennes plus on plus agrandis. Maurice Merleau-Ponty, dans son livre 'la $ph\'{e}nom\'{e}nologie$ de la perception', bien $r\'{e}sumait$ une $intersubjectivit\'{e}$ entre l' espace et nous. Selon lui, l' homme prend conscience do la forme des objets avec son environnement parce quil est un corps on interaction avec eux. Donc nous $r\'{e}f\'{e}rons$ ce livre pour notre set. Et on essayera ici d' $\'{e}tudier$ le travail do Constantin Brancusi, de Alberto Giacometti, do Richard Serra et do quelques d' autres travaux d' artistes L' oeuvre do Brancusi 'la Colonne sans fin', la taille plus de 29 m, produit one impression sur le spectateur relativement $\grave{a}$ la forme continue et $r\'{e}p\'{e}t\'{e}e$ $\`{a}$ linfini de $mani\'{e}re$ unifome. La pratique de Giacometti qui tenait compte do son envergure et de la longueur do son corps ainsi que do distance et de la mesure do sos bras, Il $d\'{e}formait$ aussi les silhouettes et transformait les objects en les $\'{e}tirant$ dans la perspective. Rosalind Krauss parler $\`{a}$ loeuvre do Serra, dans son livre 'l' originalit de lavant-garde et sutres mythes modernistes' (pp. 319-333), le spectateur est toujours on mouvement on liaison entre l' horizon do corps et celui do monde. Cette $transitivit\'{e}$ abstraite $r\'{e}ciproque$ entre le regardeur et le $regard\'{e}$, qui est comme le sujet de nombreuses oeuvres do Serra. Cependant le Maximalisme est $\`{a}$ l' origine Minimalisme qui s' $\'{e}tend$ dans ses efforts $th\'{e}oriques$ jusqu' au l' espace architecturale. Ces sculptures do grandes dimensions so situent autour de $b\^{a}timent$ ou dans lespace environnementale, comme ils sent l' architecture et le paysage. On suppose ici, leurs concepts de l' espace $\'{e}largit$ $\`{a}$ celui d' architecture. La sculpture et l' architecture $r\'{e}ciproque$ l' espace tridimensionnel entre eux, mais selon l' argument do Herbert Read pour la distinction de ces deux arts originaux sont, deux saisies de l' espace, ici englobant, $l\`{a}$ $englob\'{e}$. On $\'{e}tudie$ dans co set de concept de l' espace et de l' $\'{e}chelle$ d' objet par rapport au corps humain.

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The Effects of SO2 and NH3 on the N2O Reduction with CO over MMO Catalyst (MMO 촉매와 CO 환원제에 의한 N2O 분해에서 SO2 및 NH3 영향 연구)

  • Chang, Kil Sang;You, Kyung-Chang
    • Applied Chemistry for Engineering
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    • v.20 no.6
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    • pp.653-657
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    • 2009
  • Nitrous oxide is a typical greenhouse gas which is produced from various organic or fossil fuel combustion processes as well as chemicals producing plants. $N_2O$ has a global worming potential of 310 times that of $CO_2$ on per molecule basis, and also acts as an ozone depleting material in the stratosphere. However, its removal is not easy for its chemical stability characteristics. Most SCR processes with several effective reducing agents generally require the operation temperature higher than $450^{\circ}C$, and the catalytic conversion becomes decreased significantly when NOx is present in the stream. Present experiments have been performed to obtain basic design data of actual application concerning the effects of $SO_2$ and $NH_3$ on the interim and long term activities of $N_2O$ reduction with CO over the mixed metal oxide (MMO) catalyst derived from a hydrotalcite-like compound precursor. The MMO catalysts used in the experiments, have shown prominent activities displaying full conversions of $N_2O$ near $200^{\circ}C$ when CO is introduced. The presence of $SO_2$ is considered to show no critical behavior as can be met in the $NH_3$ SCR DeNOx systems and the effect of $NH_3$ is considered to play as mere an impurity to share the active sites of the catalysts.

Carpal Tunnel Syndrome Among Male French Farmers and Agricultural Workers: Is It Only Associated With Physical Exposure?

  • Roquelaure, Yves;Jego, Sylvaine;Geoffroy-Perez, Beatrice;Chazelle, Emilie;Descatha, Alexis;Evanoff, Bradley;Garlantezec, Ronan;Bodin, Julie
    • Safety and Health at Work
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    • v.11 no.1
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    • pp.33-40
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    • 2020
  • Background: Exploratory study to investigate whether co-exposure to physical wrist stressors and chemicals is associated with carpal tunnel syndrome (CTS) in French male farmers and agricultural workers. Methods: Cross-sectional study of 711 men aged 30-65 years and working as either farmers or agricultural workers in 2009-2010 within a cohort covered by the French Agricultural Workers' and Farmers' Mutual Benefit Fund. CTS and exposure to physical wrist stressors and chemicals were assessed using a self-administered questionnaire. Associations between CTS and personal/medical factors, exposure to physical wrist stressors, exposure to chemicals, and co-exposure to physical wrist stressors and chemicals were studied using multivariate logistic regression models. Results: Forty-four men {5.6% [95% confidence interval (CI) 4.0-7.7]} reported that they had suffered from unilateral/bilateral CTS during the last 12 months. CTS was associated with age, current smoking [odds ratio (OR) = 2.1 (1.0-4.5)], and exposure to physical wrist stressors [OR = 2.6 (1.1-5.9)]. An association was found between CTS and co-exposure to physical wrist stressors and chemicals [OR = 3.3 (0.8-14.3), p = 0.044] in comparison with the no-exposure group. Conclusions: This exploratory study shows an association of CTS with exposure to biomechanical wrist stressors in male farmers and agricultural workers and suggests an association of CTS with co-exposure to physical wrist stressors and chemicals. Owing to the limitations of the study, this result must be confirmed by a prospective study with objective assessments of the outcome and exposure before drawing conclusions on the possible synergistic effects of mechanical stressors and chemicals on the impairment of the median nerve.

Characteristics of Catalysts System of NGOC-LNT-SCR for CNG Buses (CNG 버스용 NGOC+LNT+SCR 촉매시스템의 특성)

  • Seo, Choong-Kil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.626-631
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    • 2019
  • The policy-making and technological development for the supply expansion of eco-friendly automobiles has been continuing, but the internal combustion engines still accounts for about 95%. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. This study is a basic study for the post-Euro-VI exhaust response of CNG buses, and it is to investigate the basic characteristics according to Pd substitution transition metal effect, catalyst volume effect and space velocity. A catalysts was prepared and tested using a model gas reactor. The NGOC catalyst with 3Pd exhibited the highest catalytic activity with 22% at $300^{\circ}C$, 48% at $350^{\circ}C$ and about 75% at $500^{\circ}C$. 3Co NGOC containing 3wt% of transition metal was excellent in oxidation ability, and it was small in size of 2nm, and the degree of catalyst dispersion was improved and de-NO/CO conversion was high. The volume of the NGOC-LNT-SCR catalyst system was optimal in the combination of 1.5+0.5+0.5 with a total score of 165, considering $de-CH_4/NOx$ performance and catalyst cost. For SV $14,000h^{-1}$, the $CH_4$ reduction performance was the highest at about 20%, while the SV $56,000h^{-1}$ was the lowest at about 5%. If the space velocity is small, the flow velocity decreases and the time remaining in the catalyst volume become long, so that the harmful gas was reduced.