• Title/Summary/Keyword: Random effects

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The Effects of Cognitive Bias on Entrepreneurial Opportunity Evaluations through Perceived Risks in Entrepreneurial Self-Efficacy (창업가의 인지편향이 지각된 위험과 조절된 창업효능감에 따라 창업기회평가에 미치는 영향)

  • Kim, Daeyop;Park, Jaehwan
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.1
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    • pp.95-112
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    • 2020
  • This paper is to investigate how cognitive bias of college students and entrepreneurs relates to perceived risks and entrepreneurial opportunities that represent uncertainty, and how various cognitive bias and entrepreneurial efficacy In the same way. The purpose of this study is to find improvement points of entrepreneurship education for college students and to suggest problems and improvement possibilities in the decision making process of current entrepreneurs. This empirical study is a necessary to improve the decision-making of individuals who want to start a business at the time when various attempts are made to activate the start-up business and increase the sustainability of the existing SME management. And understanding of the difference in opportunity evaluation, and suggests that it is necessary to provide good opportunities together with the upbringing of entrepreneurs. In order to achieve the purpose of the study, questionnaires were conducted for college students and entrepreneurs. A total of 363 questionnaire data were obtained and demonstrated through structural equation modeling. This study confirms that there is some relationship between perceived risk and cognitive bias. Overconfidence and control illusions among cognitive bias have a significant relationship between perceived risk and wealth. Especially, it is confirmed that control illusion of college students has a significant relationship with perceived risk. Second, cognitive bias demonstrated some significant relationship with opportunity evaluation. Although we did not find evidence that excess self-confidence is related to opportunity evaluation, we have verified that control illusions and current status bias are related to opportunity evaluation. Control illusions were significant in both college students and entrepreneurs. Third, perceived risk has a negative relationship with opportunity evaluation. All students, regardless of whether they are college students or entrepreneurs, judge opportunities positively if they perceive low risk. Fourth, it can be seen from the college students 'group that entrepreneurial efficacy has a moderating effect between perceived risk and opportunity evaluation, but no significant results were found in the entrepreneurs' group. Fifth, the college students and entrepreneurs have different cognitive bias, and they have proved that there is a different relationship between entrepreneurial opportunity evaluation and perceived risk. On the whole, there are various cognitive biases that are caused by time pressure or stress on college students and entrepreneurs who have to make judgments in uncertain opportunities, and in this respect, they can improve their judgment in the future. At the same time, university students can have a positive view of new opportunities based on high entrepreneurial efficacy, but if they fully understand the intrinsic risks of entrepreneurship through entrepreneurial education and fully understand the cognitive bias present in direct entrepreneurial experience, You will get a better opportunity assessment. This study has limitations in that it is based on the fact that university students and entrepreneurs are integrated, and that the survey respondents are selected by the limited random sampling method. It is necessary to conduct more systematic research based on more faithful data in the absence of the accumulation of entrepreneurial research data. Second, the translation tools used in the previous studies were translated and the meaning of the measurement tools might not be conveyed due to language differences. Therefore, it is necessary to construct a more precise scale for the accuracy of the study. Finally, complementary research should be done to identify what competitive opportunities are and what opportunities are appropriate for entrepreneurs.

The Health Status of Rural Farming Women (농촌여성(農村女性)의 건강실태(健康實態)에 관한 연구(硏究))

  • Park, Jung-Eun
    • Journal of agricultural medicine and community health
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    • v.15 no.2
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    • pp.97-106
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    • 1990
  • 1. Background Women's health and their involvement in health care are essential to health for everyone. If they are ignorant, malnourished or over-worked, the health &-their families as well as their own health will suffer. Women's health depends on broad considerations beyond medicine. Among other things, it depends upon their work in farming. their subordination to their families, their accepted roles, and poor hygiene with poorly equipped housing and environmental sanitation. 2. Objectives and Contents a. The health status of rural women : physical and mental complaints, experience of pesticides intoxication, Farmer's syndrome, experiences of reproductive health problems. b. participation in and attitudes towards housework and farming c. accessibility of medical care d. status of maternal health : fertility, family planning practice. induced abortion, and maternal care 3. Research method A nationwide field survey, based on stratified random sampling, was conducted during July, 1986. Revised Cornell Medical index(68 out of 195 items). Kawagai's Farmers Syndrome Scale, and self-developed structured questionnaires were used to rural farming wives(n=2.028). aged between 26-55. 4. Characteristics of the respondents mean age : 40.2 marital status : 90.8% married mean no. of household : 4.9 average years of education : 4.7 yrs. average income of household : \235,000 average years of residence in rural area : 36.4 yrs average Working hours(household and farming) : 11 hrs. 23 min 5. Health Status of rural women a. The average number of physical and mental symptoms were 12.4, 4.7, and the rate of complaints were 22.1%, 38.8% each. revealing complaints of mental symptomes higher than physical ones. b. 65.4% of rural women complained of more than 4 symptoms out of 9, indicating farmer's syndrome. 11.9 % experienced pesticide overdue syndrome c. 57.6% of respondents experienced women-specific health problems. d. Age and education of respondents were the variables which affect on the level of their health 6. Utilization of medical services a. The number of symptoms and complaints of respondents were dependent on the distance to where the health-care service is given b. Drug store was the most commonly utilized due to low price and the distance to reach. while nurse practitioners were well utilized when there were nurse practitioner's office in their villages. c. Rural women were internalized their subordination to husbands and children, revealing they are positive(93%) in health-care demand for-them but negative(30%) for themselves d. 33.0% of respondents were habitual drug users, 4.5% were smokers and 32.3% were alcohol drinkers. and 86.3% experienced induced-abortion. But most of them(77.6%) knew that those had negative effects on health. 7. Maternal Health Care a. Practice rate of contraception was 48.1% : female users were 90.9% in permanent and 89.6% in temporary contraception b. Induced abortions were taken mostly at hospital(86.3%), while health centers(4.7%), midwiferies(4.3%). and others(4.5%) including drug stores were listed a few. The repeated numbers of induced abortion seemed affected on the increasing numbers of symptoms and complaints. c. The first pre-natal check-up during first trimester was 41.8%, safe delivery rate was 15.6%, post-natal check-up during two months after delivery. Rural women had no enough rest after delivery revealing average days of rest from home work and farming 8.3 and 17.2. d. 86.6% practised breast feeding, showing younger and more educated mothers depending on artificial milk 8. Recommendations a. To lessen the multiple role over burden housing and sanitary conditions should be improved, and are needed farming machiner es for women and training on the use of them b. Health education should begin at primary school including health behavior and living environment. c. Women should be encouraged to become policy-makers as well as administrators in the field of women specific health affairs. d. Women's health indicators should be developed and women's health surveillance system too.

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The effects of career exploration programs using career portfolio and teacher-directed on the career maturity and career identity in middle school students (커리어포트폴리오형 및 교사주도형 진로탐색 프로그램이 중학생의 진로성숙도와 진로정체감에 미치는 효과)

  • Shin, Im-Sun;Jang, Yoon-Ok
    • Journal of Korean Home Economics Education Association
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    • v.24 no.1
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    • pp.85-104
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    • 2012
  • The purpose of this study was to carry out the career portfolio and the teacher-directed career exploration program in the unit of 'Industry and Career' of Technology·Home Economics and to find out how much those programs affect on career maturity and career identity in middle school students. The subjects were third-grade students who were selected at random from a middle school in Daegu. The subjects were divided into 60 for career portfolio group, 60 for teacher-directed group, and 60 for control group. Those programs were conducted totally in 9 sessions once or twice a week, and each session took 45 minutes. For pretest and post test, the questionnaire consisting of career maturity scale and career identity scale was used. To analyze data, ANCOVA was used and Scheffe test was conducted to examine significant differences between three groups. The main result of this study was the following : First, students who participate in the career portfolio and the teacher-directed career exploration program are more improved than those who have not been taught anything in determinacy and purpose of career maturity. Also, students who join in the career portfolio career exploration program are much more improved than those who join in the teacher-directed career exploration program in confidence and preparedness of career maturity. Second, students who join in the career portfolio career exploration program are more improved than those who join in the teacher-directed career exploration program in stability, goal directivity and assertiveness of career identity. Also students who participate in the lecture-oriented career exploration program are more improved meaningfully than those who have not been taught anything in the task orientation of career identity.

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EFFECTS OF MOISTENING OF ETCHED DENTIN AND ENAMEL SURFACES ON BOND STRENGTH (산 표면처리후 상아질과 법랑질 표면의 습윤이 결합강도에 미치는 영향)

  • Lee, Kwang-Won;Park, Soo-Joung;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.20 no.1
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    • pp.328-341
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    • 1995
  • I. Shear Bond Strength to Air-dried and Remoistened Dentin.. The effect of air-drying and remoistening of acid-conditioned dentin before priming with the primer of All-Bond 2(BISCO. INC., U. S. A.) on shear bond strength(SBS) was investigated. Ninty freshly extracted sound human molars were divided at random into 9 groups of 10 teeth each. SBSs were meaured for acid-conditioned and non-conditioned dentin to which the primer and bonding agent of All-Bond 2 and composite resin(Z-100, 3M Dental Products, U. S. A.) were applied. The following values(Mean${\pm}$ SD, MPa) were obtained for the groups conditioned with 10% phosphoric acid for 15 seconds: Group l(blot dried) $6.7{\pm}4.1$ ; Group 2(10 seconds dried) $16.1{\pm}5.3$ ; Group 3(20 seconds dried) $15.4{\pm}4.8$ ; Group 4(30 seconds dried) $15.2{\pm}6.3$ ; Group 5(10 seconds dried/remoistened) $26.4{\pm}2.6$ ; Group 6(20 seconds dired/remositened) $22.2{\pm}2.7$ ; Group 7(30 seconds dried/remoistened) $21.5{\pm}4.1$. For the non-conditioned groups the values were: Group 8 (blot dried) $13.3{\pm}2.6$ ; Group 9(10 seconds dried) $12.9{\pm}3.5$. The data were analyzed using ANOVA. In the acid-conditioned groups, mean values of SBS for the air-dried specimens(Grps. 2, 3 and 4) and the 20 and 30 seconds dried/remoistened specimens (Grps. 6 and 7) were significantly lower than that of blot dried specimens.(p<0.05) The value for 10 seconds dried/remoistened specimens (Grp. 5), however, was not statistically different compared to that of blot dried specimens.(p>0.05) In the non-conditined groups, there was no statistical difference between blot dried and 10 seconds dried specimens.(p>0.05) The results suggest that the acid-conditioned dentin surface is more vulnerable to dentin bonding when it is air-dried or even remoistened after long period of drying. II. Shear bond stengh to the moistened and primed enamel. The effect of moistening and priming of enamel compared to the air-drying of enamel on the shear bond strength of enamel bonding agent was investigated. The experiment was divided into 4 groups each containing 10 caries-free maxillary incisor teeth. Shear bond strength values were measured for the primed and non-primed enamel to which All-Bond 2 and Z-100 were applied. The following values(MPa) were obtained for the primed groups pretreated with 32 % phosphoric acid for 15 seconds. : Group 1 (10 seconds dried) $29.8{\pm}2.2$ ; Group 2(moistened) $26.8{\pm}5.4$. For the non-primed groups the values were: Group 3(10 seconds dried/primed) $27.6{\pm}5.0$ ; Group 4(mostened/primed) $28.2{\pm}3.5$. The data were subjected to statistical analysis using ANOVA. The results showed that mean shear bond strengths among the experimental groups were not statistically different. (p>0.05) Conclusively, It is suggested that the bonding ability to enamel is not decreased by the moistening and priming of the enamel.

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Embryo Production in Superior Hanwoo Donors and Embryo Transfer (우수 한우의 수정란 생산 및 이식)

  • Son D.S.;Han M.H.;Choe C.Y.;Choi S.H.;Cho S.R.;Kim H.J.;Ryu I.S.;Choi S.B.;Lee S.S.;Kim Y.K.;Kim S.K.;Kim S.H.;Shin K.H.
    • Journal of Embryo Transfer
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    • v.21 no.2
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    • pp.147-156
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    • 2006
  • The objective of this study was to supply excellent genetic resources to livestock farms by transferring embryos produced by genetically superior Korean cows (Hanwoo). Eighty Hanwoo donors were superovulated with gonadotropin ($Folltrpin^(R)\;or\;Antorin^(R)$) for 4 days combined with or without progesterone releasing intravaginal device (CIDR) insertion. The collected fresh or frozen-thawed embryos were transferred to 226 farm recipients. In this study, the effect of CIDR insertion in combination with gonadotropin ($Folltrpin^(R)$) treatments initiated at the random stage of estrous cycle on embryo production was evaluated and compared to conventional superovulation protocol. Moreover, the effect of gonadotropin ($Antorin^(R)$) dose in CIDR-treated Hanwoo donors on the embryo yield was determined. In addition, the effects of embryos (fresh vs. frozen-thawed), embryo transfer person, seasons and farms on the pregnancy rate were evaluated. In Hanwoo donors, CIDR insertion in combination with $Folltrpin^(R)$ treatments regardless of estrous detection resulted in increased numbers of total ova (6.5 vs. 5.8) and transferable embryos (3.9 vs. 3.2) compared to the conventional superovulation protocol (p<0.01). In CIDR-treated Hanwoo donors, the higher dose of $Antorin^(R)$ (36 vs. 28 mg) resulted in the increased number of transferable embryos (8.3 vs. 5.4, p<0.05). The embryos (fresh 43.9% vs. frozen-thawed 23.1%) and embryo transfer person (53.9 vs. $0{\sim}16.7%$) significantly affected the pregnancy rate after embryo transfer (p<0.01). These results suggest that CIDR-based superovulation protocol may be effectively used for production of superior Hanwoo embryos and, multiple ovulation and embryo transfer in Hanwoo might be effectively applied for livestock improvement if pregmancy rate with frozen-thawed embryos and embryo transfer skill would be improved.

Alterations of Heart Rate Variability upon β3-Adrenergic Receptor Polymorphism and Combined Capsaicin, Sesamin, and L-Carnitine in Humans (복합 캡사이신, 세사인, 그리고 카르니틴과 베타3 유전자 다형에 대한 심박수 변이성의 영향)

  • Shin, Ki-Ok;Kim, Hyun-Jun;Kang, Sung-Hwun
    • Journal of Life Science
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    • v.18 no.3
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    • pp.291-297
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    • 2008
  • We investigated whether 1) the combined capsaicin (75 mg), sesamin (30 mg), and L-carnitine (900 mg) (CCSC) ingestion enhances autonomic nervous system (ANS) activities including thermogenic sympathetic activity as energy metabolic modulator, 2) ${\beta}_3-AR$ polymorphism of each subject influences with ANS activity. Seven healthy males $(22.0{\pm}0.5\;yr)$ volunteered for this study. The cardiac autonomic nervous activities evaluated by means of heart rate variability of power spectral analysis were continuously measured during 5 min every 30 min for total 120 min resting condition with CCSC or placebo oral administration chosen at random. The results indicated that, there are not $Arp/Arg^{64}$ variants of the ${\beta}_3-AR$ genotypes in our subjects. There were not also significant differences in heart rate during rest between both trials. The difference of ANS activity did not reach the statistical significance between both trials. However, the significant improvement showed TOTAL power, HF component, and the indices of SNS and PNS activities before and at 30 min after CCSC ingestion (p<0.05, respectively). In conclusions, although each component of combined CCSC is associated with lipolysis and/or fat oxidation, the combined CCSC consumption is not influenced in stimulation of thermogenic sympathetic activity as modulator of energy metabolism. In rather, our results suggested that CCSC ingestion improves the balance of both SNS and PNS activities. Therefore, it will be considered many combined nutrient components for ergogenic and/or lipolysis effects as well as genetic variants affecting ANS activity in further studies.

The Correlations between Renminbi Fluctuations and Financial Results of Venture Companies in the Floating Exchange Rate (변동환율제도하의 위안화 환율변동과 벤처기업의 재무성과 간 상관관계 연구)

  • Sun, Zhong Yuan;Chang, Seog-Ju;Na, Seung-Hwa
    • 한국벤처창업학회:학술대회논문집
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    • 2010.08a
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    • pp.139-160
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    • 2010
  • On July 21st in 2005, People's Bank of China (PBOC) turned the currency peg against the U.S. dollar into managed currency system based on a basket of unnamed currencies under China's exchanged rate regime. This change means that China's enterprises are not free from currency fluctuations. The purpose of this study is to analyze the relations between Renminbi fluctuations in the floating exchange rate and financial results of venture companies. The process and outcomes of this study are as follows, First, in order to measure the financial results of venture companies, I choose venture companies in Shandong Province listed on the Shanghai Stock Exchange (SSE) at random and several quarter financial sheets according to safety ratios, profitability ratios, growth ratios, activity ratios. Second, I arrange the daily Renminbi exchange rate data announced from July 21st, 2005 to December 31st, 2008 by PBOC into the quarterly data. Third, in order to confirm the relations between Renminbi fluctuations and financial results of venture companies, I carry out Pearson's correlation analysis. As a result, the revaluation of the Chinese Renminbi has weakly negative effects on debt ratio, total assets turnover ratio and equity turnover ratio in statistics. But the revaluation of the Chinese Renminbi is not related to other financial index in statistics. The result of this study is that the revaluation of the Chinese Renminbi has little influence on the export and import of Chinese venture companies and certifies the fact that Chinese venture companies have much foreign currency assets. In addition to avoid the currency exposure risk, this study shows the effective method about currency exposure risk which adjusts proportion of Renminbi to foreign currency.

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Comparative Evaluation on Sperm Parameter of Transgenic Pigs with General Pigs (형질전환 돼지의 정자와 일반돼지의 정자성상에 대한 비교평가)

  • Park, Sang Hyoun;Lee, Gunsup;Lee, Joo Yung;Kim, Kyung Woon;Byun, Sung-June;Ock, Sun A;Hwang, Seongsoo;Yang, Hyeon;Woo, Jae-Seok;Oh, Keon Bong
    • Journal of Embryo Transfer
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    • v.32 no.3
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    • pp.227-233
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    • 2017
  • Pig has been known to be one of the most feasible animals as a bioreactor to produce pharmaceuticals in milk and as a mediator in xenotransplantation research. Previously, we generated transgenic pigs for both purposes, which were expressing Factor 8, vWF, hTPA, and hEPO in milk, along with expression of MCP at GalT gene locus ($GalT^{-MCP/-MCP}$) as well as expressing MCP at GalT gene loci with CD73 expression ($GalT^{-MCP/+}/CD73$). In this study, we performed comparative analyses of sperm parameters between wild type male (WT) pig and those transgenic males to examine the effects of transgenes integrated into the pigs on motility, morphology, viability, and acrosome integrity of the spermatozoa. Our results showed that the rates of actively motile spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 85.0%, 83.3%, 82.5%, 83.3%, 82.5%, 77.5%, and 78.7%, respectively. Whereas, the rates of morphologically normal spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 90.0%, 80.0%, 80.0%, 83.3%, 85.0%, 91.8%, and 80.8%, respectively. In addition, the viability in spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 93.9%, 82.4%, 89.9%, 83.9%, 87.4%, 92.8%, and 83.6%, respectively. The rates of spermatozoa with normal acrosome integrity in WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 98.1%, 98.6%, 98.6%, 98.7%, 98.1%, 99.5%, and 95.1%, respectively. There were no significant differences in motility, morphology, viability, and acrosome integrity of the spermatozoa among WT, Factor 8, vWF, hTPA, and hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs. These mean that neither random integration nor targeted integration of the transgene into chromosome of pig effect on characteristics of spermatozoa. Ultimately, the transgenic male pigs subjected in this study could apply to propagate their progenies for production of human therapeutic proteins and advancing the xenotransplantation research.

Genotype $\times$ Environment Interaction of Rice Yield in Multi-location Trials (벼 재배 품종과 환경의 상호작용)

  • 양창인;양세준;정영평;최해춘;신영범
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.6
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    • pp.453-458
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    • 2001
  • The Rural Development Administration (RDA) of Korea now operates a system called Rice Variety Selection Tests (RVST), which are now being implemented in eight Agricultural Research and Extension Services located in eight province RVST's objective is to provide accurate yield estimates and to select well-adapted varieties to each province. Systematic evaluation of entries included in RVST is a highly important task to select the best-adapted varieties to specific location and to observe the performance of entries across a wide range of test sites within a region. The rice yield data in RVST for ordinary transplanting in Kangwon province during 1997-2000 were analyzed. The experiments were carried out in three replications of a random complete block design with eleven entries across five locations. Additive Main effects and Multiplicative Interaction (AMMI) model was employed to examine the interaction between genotype and environment (G$\times$E) in the biplot form. It was found that genotype variability was as high as 66%, followed by G$\times$E interaction variability, 21%, and variability by environment, 13%. G$\times$E interaction was partitioned into two significant (P<0.05) principal components. Pattern analysis was used for interpretation on G$\times$E interaction and adaptibility. Major determinants among the meteorological factors on G$\times$E matrix were canopy minimum temperature, minimum relative humidity, sunshine hours, precipitation and mean cloud amount. Odaebyeo, Obongbyeo and Jinbubyeo were relatively stable varieties in all the regions. Furthermore, the most adapted varieties in each region, in terms of productivity, were evaluated.

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An Assessment of Notice Exposure by Job and Dosimeter Parameters Setting in Automobile Press Factory (자동차 프레스 공정에 있어서 직무 및 누적소음기 설정치 차이에 따른 작업자의 소음노출 평가)

  • Jeong, Jee Yeon;Park, Seunghyun;Yi, GwangYong;Lee, Naroo;You, Ki Ho;Park, Junsun;Chung, Ho Keun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.11 no.3
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    • pp.190-197
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    • 2001
  • Noise-induced hearing loss(NIHL) was the highest rate (43.5%~58.5% from 1996 to 1998) of positive findings through specific medical program in Korea. There were much more NIHL at workers of automobile manufacturing factories than other manufacturing factories. The specific aim of the present study was to determine the noise exposure of automobile press lines, according to their job titles, press line types(auto, semiauto), dosimeter parameters setting. There were a total 11 press lines sampled at a automobile manufacturing company. Among those press lines, 10 press lines were autolines with acoustic enclosure, one semiauto press line was no aucostic enclosure Noise exposure data were sampled for an work shift using noise dosimeter, which recorded both time-weighted average(TWA) and 1-min average. The mean OSHA TWA(Korea TWA with threshold 90) was $80.7dB(A){\pm}4.7dB(A)$ for leader, $82.8dB(A{\pm}4.5dB(A)$ for pallette man, $76.7dB(A){\pm}4.3dB(A)$ for press operators, $76.6dB(A){\pm}5.6dB(A)$ for crane operators, $77.1dB(A){\pm}2.8dB(A)$ for forklift drivers, whereas the mean NIOSH TWA was $88.9dB(A){\pm}1.7dB(A)$ for leader, $89.6dB(A){\pm}2.1dB(A)$ for pallette man, $86.7dB(A){\pm}1.8dB(A)$ for press operators, $88.5dB(A){\pm}2.0dB(A)$ for crane operators, $87.7dB(A){\pm}1.0dB(A)$ for forklift drivers. While L10 for NIOSH TWA samples was 84.8 dB(A) ~ 87.3 dB(A), L10 for OSHA TWA samples was 69.5 dB(A) ~ 77.4 dB(A). L10 means that the TWA for 90% of the samples exceeded L10. Among OSHA TWA(Korea TWA with threshold 90) samples for pallette man, 7.7 % exceeded 90 dB(A), the OSHA permissible exposure level, but OSHA TWA samples for the other job titles didn't. Among NIOSH TWA samples, the samples over 85 dB(A), the NIOSH recommended exposure limit, was 100% (leaders), 83.3 %(operators), 97.4%(palletteman), 100%(forklift drivers), 91.7 %(crane operator). The results of One-way random effects analysis of variance models shows that the difference between job titles was significant by OSHA TWA(p<0.05), but not significant by NIOSH TWA(p>0.05). NIOSH TWA samples were significantly higher than OSHA TWA samples(P<0.05). Regression analysis was used to obtain relationships between OSHA TWA samples and NIOSH TWA samples. In this case the coefficient of determination = 0.90, which shows the high degree association between two methods. Regression equation, NIOSH TWA = 0.552 * OSHA TWA + 42.13 dB(A), shows that if OSHA TWA is known, NIOSH TWA can be predicted by the equation. The mean TWA difference between threshold 80 dBA and 90 dBA was significant(p<0.01). While the TWA noise exposures were 7.7% above the Korea(OSHA) PEL, they were more than 83.3% over NIOSH REL. Automobile workers were exposed to noise level that could be potentially damaging to their hearing. It found that there is approximately 25% excess risk of hearing loss even if a worker is protected to the PEL in according to NIOSH study.

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