• Title/Summary/Keyword: tolerance analysis

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The Impact of Psychosocial Protective and Risk Factors on Problem Drinking among American Adolescents: Focused on Compensatory and Buffering Effects of Protective Factors (미국 청소년의 문제성 음주에 대한 심리사회적 보호변인과 위험변인의 역할 - 보호변인의 보상효과와 완충효과를 중심으로 -)

  • Kim, Young-Mi
    • Korean Journal of Social Welfare
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    • v.56 no.4
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    • pp.269-290
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    • 2004
  • The purpose of this study was to examine the impact of psychosocial protective and risk factors on problem drinking among American adolescents. In addition, this study investigated the compensatory and buffering effects of psychosocial protective factors. The sample consisted 4,362 10th graders taken from the Monitoring the Future Study 2002. This study performed the hierarchical regression analysis for data analyses. The main findings provided that friend influence, sensation-seeking, and tolerance of deviance had significant positive relationships with problem drinking as risk factors. This study also revealed that negative perception on drinking, parental bonding, school bonding, and prosocial activity had significant direct impacts in decreasing problem drinking, which explains the compensatory effect of protective factors. Additionally, this study showed that negative perception on drinking had a significant buffering effect moderating friend influence on adolescents' opportunities exposed to problem drinking. The results of this study suggest some practical implications for preventive intervention programs that target adolescent problem drinking.

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A Study of Methane Oxidation over Transition Metal (TM)/CeO2 (TM=Ni, Co, Cu, Fe) (전이금속이 담지된 세리아의 메탄 산화 반응에 대한 연구)

  • Ahn, Ki-Yong;Chung, Yong-Chae;Lee, Jong-Ho
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.4
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    • pp.346-352
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    • 2012
  • The properties of methane oxidation were studied in this research over transition metal containing $CeO_2$ (TM/$CeO_2$, TM=Ni, Co, Cu, Fe) with TM content of 5 wt. % at atmospheric pressure. The characteristics of catalysts were investigated by various characterization techniques, including XRD, GC, SEM and EPMA analyses. The catalytic tests were carried out in a fixed Rmix ratio of 1.5 ($CH_4/O_2$) in a fixed-bed reactor operating isothermally at atmospheric pressure. Only the Ni/$CeO_2$ catalysts showed syngas production above $400^{\circ}C$ via typical partial oxidation reaction whereas other catalysts induced complete oxidation resulting in the production of $CO_2$ and $H_2O$ in whole reaction temperature range. From the quantitative analysis on carbon deposition after catalytic tests, Cu/$CeO_2$ was found to show the highest resistance on carbon deposition. Therefore Cu can be proposed as an efficient catalyst element which can be combined with a conventional Ni-based SOFC anode to enhance the carbon tolerance.

Characteristics Analysis for Voltage, Current & Capacity of Condenser at Voltage Unbalance (전압 불평형시 콘덴서 전압, 전류, 용량 특성 해석)

  • Kim, Jong-Gyeum;Park, Young-Jeen
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.5
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    • pp.145-151
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    • 2010
  • Voltage unbalance is regarded as a power quality problem of significant at the user application. Although the voltages are quite well balanced at the transmission system, the voltage level of utilization can be unbalanced due to the unequal system impedances and the unequal distribution of single phase loads. Capacitor is generally used for power-factor compensation and reducing harmonics of non linear load with reactor. If voltage unbalance exists, current unbalance is generated and it will be reflected in the capacity variance. When the reactor and condenser are used at the same location, generally its trouble rate is high. And it is very important checking out that how the variance of voltage, current and capacity of condenser is proceeded by the voltage unbalance. In this paper, we calculated that voltage, current and capacity of condenser are within the tolerance limit of official regulations in the event of voltage unbalance with/without reactor.

Arthropod Diversity and Community Structure in Fields of Non-genetically Modified (GM) and Herbicide-tolerant GM Rice (PPO 저해 제초제 내성 유전자변형 벼가 절지동물군집에 미치는 영향)

  • Kim, Young-Joong;Lee, Joon-Ho;Back, Kyoungwhan;Kim, Chang-Gi
    • Korean journal of applied entomology
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    • v.54 no.4
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    • pp.335-343
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    • 2015
  • One of the primary concerns about the environmental risks of genetically modified (GM) crops is that they may have adverse effects on the local arthropod communities. In this study, we investigated whether the arthropod diversity and community structure in fields of GM rice tolerant to protoporphyrinogen oxidase (PPO)-inhibiting herbicides differ from those in non-GM (control) rice fields. The aim of this study was to assess the potential adverse effects of GM rice on the local arthropod communities. During the growing seasons in the study period, we collected arthropods from both fields by using yellow sticky traps and compared the diversity and community structure of arthropods from the two sites. Overall, the GM rice had no significant effect on the diversity of the local arthropod communities. In addition, multivariate analyses (permutational multivariate analysis of variance and nonmetric multidimensional scaling) showed that the structures of arthropod communities were not affected by the rice genotype (GM vs. non-GM), although these comparisons were made using data obtained at different sampling dates.

A Study on Stratified Charge GDI Engine Development - Combustion Analysis according to the Variations of Injection Pressure and Load - (연소실 직접분사식 성층급기 가솔린기관 개발에 관한 연구 - 연료분사압력과 부하변동에 따른 연소특성 해석 -)

  • Lee, Sang Man;Jeong, Young Sik;Chae, Jae Ou
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.9
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    • pp.1317-1324
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    • 1998
  • In general, DI gasoline engine has the advantages of higher power output, higher thermal efficiency, higher EGR tolerance and lower emissions due to the operation characteristics of increased volumetric efficiency, compression ratio and ultra-lean combustion scheme. In order to apply the concept of stratified charge into direct injection gasoline engine, some kinds of methodologies have been adapted in various papers. In this study, a reflector was adapted around the injector nozzle to apply the concept of stratified charge combustion which leads the air-fuel mixture to be rich near spark plug. Therefore, the mixture near the spark plug is locally rich to ignite while the lean mixture is wholly introduced into the combustion chamber. The characteristics of combustion is analyzed with the variations of fuel injection pressure and load in a stratified -charge direct injection single cylinder gasoline engine. The obtained results are summarized as follows ; 1. The MBT spark timing approached to TDC with the increase of load on account of the increase of evaporation energy, but has little relation with fuel injection pressure. 2. The stratification effects are apparent with the increase of injection pressure. It is considered by the development of secondary diffusive combustion and the increase of heat release of same region, but proceed rapidly than diesel engine. Especially, in the case of high pressure injection (l70bar) and high load (3.0kgf m), the diffusive combustion parts are developed excessively and results in the decrease of peak pressure than in the case of middle load. 3. The index of engine stability, COVimep value, is drastically decreased with the increase of load. 4. To get better performance of DI gasoline engine development, staged optimizaion must be needed such as injection pressure, reflector, intake swirl, injection timing, chamber shape, ignition system and so on. In this study, the I50bar injection pressure is appeared as the optimum.

5 Cases of Acute Pyelonephritis (급성(急性) 신우신염(腎盂腎炎)의 임상적(臨床的) 고찰(考察))

  • Kwon, Jeong-Nam;Kim, Young-Kyun;Ryu, Ju-Yeol
    • Journal of Sasang Constitutional Medicine
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    • v.13 no.2
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    • pp.194-204
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    • 2001
  • Purpose: In general, Acute Pyelonephritis is effectively treated with the use of antibiotics. However, some antibiotics are reported to cause side effects, and the abuse of antibiotics results in the increase of the disease's tolerance to antibiotics. Recently, I have effectively treated five cases of Acute Pyelonephritis by using only Constitution - Acupuncture and Herb, and therefore I would like to report about these cases. Methods: I diagnosed Acute Pyelonephritis of these five patients by confirming symptoms and employing a urine analysis with reagent strip(Multi $stix{\circledR}$). I used Kuon's method of constitutional diagnosis for the purpose of the diagnosis of the constitutional 8 morbidities. I relied on Sungjeong(性情) and Chehyungkisang(體刑氣像) in diagnosing Sasang Constitutions(四象人). I performed acupuncture on the left and right sides, depending on 8 constitutions, by employing Chang - temperament Inflammation Formula(臟系炎症方) that is used for the treatment of all kinds of chang-temperament inflammation diseases, as well as Bactericidal Formula(殺菌方) that is used for the treatment of all kinds of bacterially caused diseases. I prescribed by consulting the appearance of disease and general symptoms of each case with Dongyi Soose Bowon(東醫壽世保元)'s prescription symptoms. Result: Two of them showing severe symptoms were hospitalized, while three others took OPD treatment. The patient who was PANCREOTONIA and Soyangin improved through hospitalization for three days, another patient who was PULMOTONIA and Taeyangin with severe symptoms, improved through hospitalization for seven days, and completely recovered through OPD treatment later. The three others took only OPD treatment, and improved within 5-7 days. Conclusion: I confirmed that each of 8-constituions and Sasang Constitutions were all treated effectively without antibiotics.

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Effect of Amylase and Emulsifier on the Characteristics of the Bread Dough (Amylase와 유화제의 첨가가 빵 반죽특성에 미치는 영향)

  • Park, Bum-Joon;Hwang, Seong-Yun;Park, Cheon-Seok
    • Korean Journal of Food Science and Technology
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    • v.37 no.5
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    • pp.763-767
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    • 2005
  • Effect of ${\alpha}-amylase$ and various emulsifiers on characteristics of bread dough were examined. Fungal or bacterial ${\alpha}-amylase$ and various emulsifiers including monoglyceride (MG), sodium stearoyl-2-lactylate (SSL), and diacetyltartaric acid ester of mono- and diglycerides (DATEM) were added to bread dough both individually and as mixtures. Rheological characteristics of various bread doughs were examined through falling number, farinograph, alveograph, and rapid visco analysis. Results obtained showed falling number decreased via degradation of starch by ${\alpha}-amylase$. In farinogram, addition of ${\alpha}-amylase$ and emulsifiers in dough decreased consistency, water absorption, mechanical tolerance index, and dough development time. Farinogram characteristic was improved by adding SSL+MG to dough formula. Similar to farinogram addition of ${\alpha}-amylase$ and emulsifiers in alveogram of dough decreased overpressure, extensibility, swelling index, and deformation energy. Whereas addition of ${\alpha}-amylase$ did not affect pasting temperature, viscosity of dough tended to decrease.

Antagonistic Regulation of Arabidopsis Growth by Brassinosteroids and Abiotic Stresses

  • Chung, Yuhee;Kwon, Soon Il;Choe, Sunghwa
    • Molecules and Cells
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    • v.37 no.11
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    • pp.795-803
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    • 2014
  • To withstand ever-changing environmental stresses, plants are equipped with phytohormone-mediated stress resistance mechanisms. Salt stress triggers abscisic acid (ABA) signaling, which enhances stress tolerance at the expense of growth. ABA is thought to inhibit the action of growth-promoting hormones, including brassinosteroids (BRs). However, the regulatory mechanisms that coordinate ABA and BR activity remain to be discovered. We noticed that ABA-treated seedlings exhibited small, round leaves and short roots, a phenotype that is characteristic of the BR signaling mutant, brassinosteroid insensitive1-9 (bri1-9). To identify genes that are antagonistically regulated by ABA and BRs, we examined published Arabidopsis microarray data sets. Of the list of genes identified, those upregulated by ABA but downregulated by BRs were enriched with a BRRE motif in their promoter sequences. After validating the microarray data using quantitative RT-PCR, we focused on RD26, which is induced by salt stress. Histochemical analysis of transgenic Arabidopsis plants expressing RD26pro:GUS revealed that the induction of GUS expression after NaCl treatment was suppressed by co-treatment with BRs, but enhanced by co-treatment with propiconazole, a BR biosynthetic inhibitor. Similarly, treatment with bikinin, an inhibitor of BIN2 kinase, not only inhibited RD26 expression, but also reduced the survival rate of the plant following exposure to salt stress. Our results suggest that ABA and BRs act antagonistically on their target genes at or after the BIN2 step in BR signaling pathways, and suggest a mechanism by which plants fine-tune their growth, particularly when stress responses and growth compete for resources.

Field Distribution of the Reverberation Chamber with Flat Diffusers Composed of Multiple Dielectric Materials (다중 유전체로 구성된 평탄형 Diffuser가 부착된 잔향실 내의 전자기장 분포에 관한 연구)

  • Kim, Young-Ryoul;Kim, Hye-Kwang;Rhee, Joong-Geun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.5 s.120
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    • pp.471-477
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    • 2007
  • This paper presents the characteristics of electromagnetic field uniformity in a reverberation chamber with flat diffusers composed of multiple dielectric materials that can be used as an alternative facility for the analysis, test and evaluation of electromagnetic interference and immunity. The field characteristics and the size of the test volume inside the reverberation chamber with the new diffuser of multiple dielectric materials are simulated and analyzed at $2.5{\sim}3$ GHz band. The FDTD method is used to analyze the field characteristics. The field uniformity, polarization characteristics and tolerance are improved by the new diffuser with smaller physical size. The reverberation chamber with flat diffusers composed of multiple dielectric materials shows better electromagnetic performance and larger test volume than normal chamber.

Marine Environmental Characteristics of Seagrass Habitat in Seomjin River Estuary (섬진강 하구역 잘피(Z. marina)서식지의 해양환경 특성)

  • Ji, Hyeong-Seok;Seo, Hee-Jeong;Kim, Myeong-Won;Lee, Moon Ock;Kim, Jongkyu
    • Journal of Ocean Engineering and Technology
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    • v.28 no.3
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    • pp.236-244
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    • 2014
  • This study considered a seagrass habitat in order to analyze the characteristics of a marine environment of seagrass located in the Seomjin river estuary, through an analysis of the distribution of the water depth, field observation, and three-dimensional numerical experiments using an EFDC model. The seagrass habitat was usually distributed at D.L(-) 0.5~0.0 m, and was hardly seen in the intertidal zone higher than that range. The distribution of the water temperature was within the range of $7.0{\sim}23.2^{\circ}C$, and the seagrass was demonstrated to have a strong tolerance to changes in the water temperature. In addition, the salinity distribution was found to be 27.2~31.0 psu, with suspended solids of 32.1 mg/L, which were higher than the previous research results (Huh et al., 1998), implying that there may be a reduction in the amount of deposits caused by the suspended solids. As for the sedimentary facies, they were comprised of 62.7% sand, 19.1% silt, and 18.2% clay, indicating that the arenaceous was superior and the sedimentary facies were similar to that of Dadae Bay. According to a numerical experiment, the maximum tidal current was 75 cm/s, while the tidal residual current was 10 cm/s, confirming that it sufficiently adapted to strong tidal currents. The erosion and deposition are predicted to be less than 1.0 cm/year. Thus, it is judged that the resuspension of sediments due to tidal currents and the changes in sedimentary facies are insignificant.