• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.40-45
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• 1999

The effect of the addition of helium, neon, argon and xenon on the production of negative hydrogen ions has been studied in a magnetically confined dc filament discharge. The addition of helium and neon produced effects similar to an equivalent increase in hydrogen pressure. However, the addition of argon and low fractions of xenon produced significant increases in the negative ion density for hydrogen at pressures around 1 mTorr. The addition of argon and xenon, by increasing electron density and decreasing electron temperature, achieved conditions closer to optimum for negative ion production. The largest enhancement of negative hydrogen ion density occurred with the addition of argon; it is suggested that this is due to a resonant energy exchange between excited argon atoms and hydrogen molecules.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.85-91
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• 2016

Recently, luxury research has been interested the basis of the effect of charity on luxury brand. Some of their results showed that guilt reduction plays an important role in this mechanism. Current research focuses on the moderating effect of negative perception of production on the effect of charity and the moderated mediation of guilt reduction. An experiment using a well-known luxury brand is conducted. Results show that charity influences purchase intent toward luxury branded product positively and negative perception of production's main effect is negative. Charity x Production perception is significant. More importantly, moderated mediation of guilt reduction was significant, showing the mediated effect is greater when participants perceive the production negatively. Findings of this research provide theoretical and practical implications for the marketing of luxury brands, suggesting the new perspectives of ethic perception effect of production.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.683-686
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• 1999

Four mutants of Acetobacter xylinum BRC5 defective in gluconic acid production were isolated from UV-irradiated cells. The gluconic acid-negative mutants did not show glucose oxidase activity. The mutants were also defective in cellulose production. A randomly selected mutant grown in the Hestrin-Schramm medium (pH 6.0) supplemented with gluconic acid, however, was found to synthesize cellulose. The mutant grown in Hestrin-Schramm medium whose pH was adjusted to 5.0 with HC1 and contained no gluconic acid also produced cellulose. Wild-type cells grown under the same condition synthesized cellulose more rapidly than those grown in the pH 6.0 medium.

• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.41-45
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• 1999

Microbial cellulose has many potential applications due to its excellent physical properties. The production of cellulose from Acetobacter xylinum in submerged culture is, however, beset with numerous problems. The most difficult one has been the appearance of negative mutants under shaking culture conditions, which is deficient of cellulose producing ability. Thus genetic instability of Acetobacter xylinum under shaking culture condition made developing a stable mutant major research interest in recent years. To find a proper type of bioreactor for the production of microbial cellulose, several production systems were developed. Using a reactor system with planar type impeller with bottoms sparging system, it was possible to produce 5 g/L microbial cellulose without generating cellulose minus mutants, which is comparable to that of static culture system.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.511-515
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• 2007

White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSSV-PCR-negative fly epidemiologically decreases white-spot disease outbreaks. Here, we report a retrospective analysis of data from shrimp farms in the western coast of Korea where WSSV-PCR-negative brood stocks were used to stock rearing ponds. A total of 366 shrimp from Heuksan Island were sampled for WSSV with PCR. Of the tested shrimp, 7.2% (28 brood stocks) were identified as WSSV positive; only WSSV-PCR-negative shrimp were used for brood stocks. Total unit production (final shrimp production/ the area of the ponds) was higher, at 1.96, in ponds where WSSV-PCR-negative shrimp were used, as compared with 1.02 in other ponds in Korea in 2004. This retrospective analysis of WSSV in Korea may be useful to the shrimp aquaculture industry, suggesting a testable hypothesis that may contribute to the eventual control of WSSV outbreaks.

• Environmental and Resource Economics Review
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• v.12 no.1
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• pp.121-135
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• 2003

The main purpose of this paper is to estimate environmental preference of advanced countries for water and air pollution. In doing so, we introduce home production. That is, we assume that pollution has not only negative effect on utility but also positive effect on production. Thus if the former is greater that the latter effect, the total effect of pollution is negative. In this paper, we investigated this effect of advanced countries by using GMM estimator. The main finding is that in case of air pollution. This effect is negative. This implies that in case of air pollution, the disutility effect is greater that productivity effect.

• Phonetics and Speech Sciences
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• v.8 no.4
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• pp.71-78
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• 2016

The purpose of this study is to investigate the effect of Japanese(L1) on the production of Korean accentual phrases(L2). Korean and Japanese have a similar prosodic structure. But different from Korean, Japanese is a pitch accent language. So each word has its own pitch accent. And pitch accents are maintained in the sentence intonation. This difference will have a negative influence on the production of Korean sentence intonation. For this study 4 Korean natives speakers and 10 advanced Japanese learners of Korean participated in the production test. The material analysed constituted 11 Korean sentences, six of which contain formally identical Sino-Korean and Sino-Japanese words. The results show that the initial pitch pattern of Korean accentual phrases was affected by Japanese pitch accent types and this interference was greater for formally identical Sino-Korean and Sino-Japanese words. But besides initial tones of accentual phrase, some positive interference was observed in the internal tonal pattern of accentual phrase. In the phonetic realization, the internal pitch range and initial pitch rising of accentual phrases was greater for Japanese learners of Korean than native speakers of Korean.

• The Journal of the Korean Society for Microbiology
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• v.9 no.1
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• pp.33-40
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• 1974

On the basis of pigment production and growth rate on L-J medium containing crocin, differentiation of opportunist mycobacteria belonging to photochromogens, scotochromogens, nonchromogens and rapid grower has been investigated. Among photochromgens, positive pigmentation of M. kansasii was differentiated from negative strain of M. marinum, Scotochromogen M. aquae was positive whereas M. scrofulaceum was negative. Rapid grower M. fortuitum was positive at 3 days test whereas M. smegmatis was negative. Subdivision of opportunist mycobacteria into four groups on the basis of growth rate and pigment production on L J medium containing gardenia extraction appeared to be a valuable adjunct to the Runyon's classification for the rapid presumptive identification of opportunist mycobacteria of different clinical significance.

• Journal of the Korean Home Economics Association
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• v.37 no.2
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• pp.145-158
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• 1999

The purpose of this study is to investigate the relationship between work-family conflict and job-life satisfaction of married female workers. Two data sets were used in this study. Both data sets were gathered from structured questionnaires and time dairies. The first data set was collected from 370 married female production workers in 1995 and the second set was collected from 143 married female clerical workers in 1996. Job and life satisfaction were measured on 5-point Likert scale where 5= very unsatisfied and 5= very satisfied. The overact means for both groups were 2.97, 3.09 for job and life satisfaction respectively The findings of this study are; 1) Clerical workers have significantely higher job and life satisfaction than production workers. 2) Multivariate analysis reveal that work-family conflict is negatively related to job satisfaction while income is positively related to job satisfaction. 3) In the path analysis model, work-family conflict has a negative direct effect and indirect negative effect mediated through job satisfaction on life satisfaction. Job satisfaction and husband's division of housework have a positive direct effect on life satisfaction. However, total labor time has a negative indirect effect mediated through work-family conflict on life satisfaction and income huts a positive indirect effect mediated through job satisfaction on life satisfaction.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.825-833
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• 2011

Forty-five Hisex commercial layers and forty-five local Saudi breed layers were used to determine the acceptable limit of short-term water restriction in the late phase of production, when the problem of high feed and water consumption is expected. The experiment was performed under hot and arid environmental conditions when the layers were at fifty weeks of age. Layers from each breed were randomly assigned in groups of five into nine floor pens. The average environmental temperature was 37.2-$38.6^{\circ}C$, and the relative humidity was between 20 to 37%. The trial was divided into 3 periods; control (1 week), water restriction (2 weeks) and rehydration (1 week). During the restriction period, layers from each breed were divided into three groups that received 20, 40, and 0% restriction of drinking water relative to their consumed water during the control period. During the study, feed and water consumption, body weight, changes in body weight, egg production, primary antibody response to SRBC, and rectal temperature were evaluated. Water restriction did not result in any clear effect on feed intake in either breed, however, commercial layers tended to consume less feed compared to the local breed. Body weight declined with water restriction during the first week of restriction in the commercial breed regardless of rate of restriction, but it was delayed until the second week in the local breed. Water restriction of 40% decreased egg production in both breeds but with a delay of 1 week in the local breed. Antibody level to SRBC was not affected by water restriction in the commercial line while it was highly affected in the local breed. A water restriction of 20% is considered to be an acceptable limit under the current experimental conditions without a negative effect on egg production in both breeds and considering the immune status of the local breed. Whereas, 40% restriction had a negative effect on egg production, and varied effects in the other traits in both breeds.