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The Relations between Financial Constraints and Dividend Smoothing of Innovative Small and Medium Sized Enterprises (혁신형 중소기업의 재무적 제약과 배당스무딩간의 관계)

  • Shin, Min-Shik;Kim, Soo-Eun
    • Korean small business review
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    • v.31 no.4
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    • pp.67-93
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    • 2009
  • The purpose of this paper is to explore the relations between financial constraints and dividend smoothing of innovative small and medium sized enterprises(SMEs) listed on Korea Securities Market and Kosdaq Market of Korea Exchange. The innovative SMEs is defined as the firms with high level of R&D intensity which is measured by (R&D investment/total sales) ratio, according to Chauvin and Hirschey (1993). The R&D investment plays an important role as the innovative driver that can increase the future growth opportunity and profitability of the firms. Therefore, the R&D investment have large, positive, and consistent influences on the market value of the firm. In this point of view, we expect that the innovative SMEs can adjust dividend payment faster than the noninnovative SMEs, on the ground of their future growth opportunity and profitability. And also, we expect that the financial unconstrained firms can adjust dividend payment faster than the financial constrained firms, on the ground of their financing ability of investment funds through the market accessibility. Aivazian et al.(2006) exert that the financial unconstrained firms with the high accessibility to capital market can adjust dividend payment faster than the financial constrained firms. We collect the sample firms among the total SMEs listed on Korea Securities Market and Kosdaq Market of Korea Exchange during the periods from January 1999 to December 2007 from the KIS Value Library database. The total number of firm-year observations of the total sample firms throughout the entire period is 5,544, the number of firm-year observations of the dividend firms is 2,919, and the number of firm-year observations of the non-dividend firms is 2,625. About 53%(or 2,919) of these total 5,544 observations involve firms that make a dividend payment. The dividend firms are divided into two groups according to the R&D intensity, such as the innovative SMEs with larger than median of R&D intensity and the noninnovative SMEs with smaller than median of R&D intensity. The number of firm-year observations of the innovative SMEs is 1,506, and the number of firm-year observations of the noninnovative SMEs is 1,413. Furthermore, the innovative SMEs are divided into two groups according to level of financial constraints, such as the financial unconstrained firms and the financial constrained firms. The number of firm-year observations of the former is 894, and the number of firm-year observations of the latter is 612. Although all available firm-year observations of the dividend firms are collected, deletions are made in the case of financial industries such as banks, securities company, insurance company, and other financial services company, because their capital structure and business style are widely different from the general manufacturing firms. The stock repurchase was involved in dividend payment because Grullon and Michaely (2002) examined the substitution hypothesis between dividends and stock repurchases. However, our data structure is an unbalanced panel data since there is no requirement that the firm-year observations data are all available for each firms during the entire periods from January 1999 to December 2007 from the KIS Value Library database. We firstly estimate the classic Lintner(1956) dividend adjustment model, where the decision to smooth dividend or to adopt a residual dividend policy depends on financial constraints measured by market accessibility. Lintner model indicates that firms maintain stable and long run target payout ratio, and that firms adjust partially the gap between current payout rato and target payout ratio each year. In the Lintner model, dependent variable is the current dividend per share(DPSt), and independent variables are the past dividend per share(DPSt-1) and the current earnings per share(EPSt). We hypothesized that firms adjust partially the gap between the current dividend per share(DPSt) and the target payout ratio(Ω) each year, when the past dividend per share(DPSt-1) deviate from the target payout ratio(Ω). We secondly estimate the expansion model that extend the Lintner model by including the determinants suggested by the major theories of dividend, namely, residual dividend theory, dividend signaling theory, agency theory, catering theory, and transactions cost theory. In the expansion model, dependent variable is the current dividend per share(DPSt), explanatory variables are the past dividend per share(DPSt-1) and the current earnings per share(EPSt), and control variables are the current capital expenditure ratio(CEAt), the current leverage ratio(LEVt), the current operating return on assets(ROAt), the current business risk(RISKt), the current trading volume turnover ratio(TURNt), and the current dividend premium(DPREMt). In these control variables, CEAt, LEVt, and ROAt are the determinants suggested by the residual dividend theory and the agency theory, ROAt and RISKt are the determinants suggested by the dividend signaling theory, TURNt is the determinant suggested by the transactions cost theory, and DPREMt is the determinant suggested by the catering theory. Furthermore, we thirdly estimate the Lintner model and the expansion model by using the panel data of the financial unconstrained firms and the financial constrained firms, that are divided into two groups according to level of financial constraints. We expect that the financial unconstrained firms can adjust dividend payment faster than the financial constrained firms, because the former can finance more easily the investment funds through the market accessibility than the latter. We analyzed descriptive statistics such as mean, standard deviation, and median to delete the outliers from the panel data, conducted one way analysis of variance to check up the industry-specfic effects, and conducted difference test of firms characteristic variables between innovative SMEs and noninnovative SMEs as well as difference test of firms characteristic variables between financial unconstrained firms and financial constrained firms. We also conducted the correlation analysis and the variance inflation factors analysis to detect any multicollinearity among the independent variables. Both of the correlation coefficients and the variance inflation factors are roughly low to the extent that may be ignored the multicollinearity among the independent variables. Furthermore, we estimate both of the Lintner model and the expansion model using the panel regression analysis. We firstly test the time-specific effects and the firm-specific effects may be involved in our panel data through the Lagrange multiplier test that was proposed by Breusch and Pagan(1980), and secondly conduct Hausman test to prove that fixed effect model is fitter with our panel data than the random effect model. The main results of this study can be summarized as follows. The determinants suggested by the major theories of dividend, namely, residual dividend theory, dividend signaling theory, agency theory, catering theory, and transactions cost theory explain significantly the dividend policy of the innovative SMEs. Lintner model indicates that firms maintain stable and long run target payout ratio, and that firms adjust partially the gap between the current payout ratio and the target payout ratio each year. In the core variables of Lintner model, the past dividend per share has more effects to dividend smoothing than the current earnings per share. These results suggest that the innovative SMEs maintain stable and long run dividend policy which sustains the past dividend per share level without corporate special reasons. The main results show that dividend adjustment speed of the innovative SMEs is faster than that of the noninnovative SMEs. This means that the innovative SMEs with high level of R&D intensity can adjust dividend payment faster than the noninnovative SMEs, on the ground of their future growth opportunity and profitability. The other main results show that dividend adjustment speed of the financial unconstrained SMEs is faster than that of the financial constrained SMEs. This means that the financial unconstrained firms with high accessibility to capital market can adjust dividend payment faster than the financial constrained firms, on the ground of their financing ability of investment funds through the market accessibility. Futhermore, the other additional results show that dividend adjustment speed of the innovative SMEs classified by the Small and Medium Business Administration is faster than that of the unclassified SMEs. They are linked with various financial policies and services such as credit guaranteed service, policy fund for SMEs, venture investment fund, insurance program, and so on. In conclusion, the past dividend per share and the current earnings per share suggested by the Lintner model explain mainly dividend adjustment speed of the innovative SMEs, and also the financial constraints explain partially. Therefore, if managers can properly understand of the relations between financial constraints and dividend smoothing of innovative SMEs, they can maintain stable and long run dividend policy of the innovative SMEs through dividend smoothing. These are encouraging results for Korea government, that is, the Small and Medium Business Administration as it has implemented many policies to commit to the innovative SMEs. This paper may have a few limitations because it may be only early study about the relations between financial constraints and dividend smoothing of the innovative SMEs. Specifically, this paper may not adequately capture all of the subtle features of the innovative SMEs and the financial unconstrained SMEs. Therefore, we think that it is necessary to expand sample firms and control variables, and use more elaborate analysis methods in the future studies.

A study on the impacts of infection control education on dental hygienists' perceptions for hepatitis type B and their practices to prevent infection (감염관리교육이 서울지역 치과위생사의 B형 간염에 대한 인식 및 감염방지행위 실천에 미치는 영향에 관한 연구)

  • Kim, Bo-Young;Park, Ji-Man;Park, Eun-Jin
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.4
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    • pp.287-297
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    • 2014
  • Purpose: The purpose of this study is to examine the impacts of infection control education on dental hygienists' perceptions for hepatitis B and their behaviors. Materials and methods: Study participants were chosen by random selection among dental hygienists working in Seoul, Korea. A total of 150 questionnaires were sent out for the survey from April 2013 to May 2013, of which 140-excluding incomplete responses-were used for the study. Chi-square tests and t-tests were used (SPSS 19.0), and post-hoc analysis was performed as well. The maximum significance level was 0.05. Results: Average 1.53 times infection control education was taken, but dental hygienists' perceptions for hepatitis B and their behaviors did not show statistical differences whether the education was done or not. Practices to prevent infection showed differences depending on categories, especially disinfection and sterilization were well performed by educated group. The most common reasons for not taking the education and noncompliance with infection prevention guidelines are lack of time and opportunity due to busy schedule. Conclusion: 1. The more highly educated, the greater number of patients per day, and the greater size of hospitals, the better infection control education was conducted. 2. Although hepatitis B is one of the most common chronic liver diseases in Korea, no significant correlation between perceptions of hepatitis B and infection control education was found. 3. Dental hygienists who received infection control education performed more efficient practices for protection against infections than those who did not.

Studies on Genetic Diversity and Phylogenetic Relationships of Korean Native Chicken using the Microsatellite Marker (Microsatellite Marker를 활용한 한국 토종닭 품종의 유전적 다양성 및 유연관계 분석)

  • Seo, Joo Hee;Oh, Jea-Don;Lee, Jun-Heon;Seo, Dongwon;Kong, Hong Sik
    • Korean Journal of Poultry Science
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    • v.42 no.1
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    • pp.15-26
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    • 2015
  • In this study, genotyping was executed by using 27 microsatellite markers for genetic diversity of 469 Korean Native Chickens [20 population, each population is 24 samples but Hanhyup A line is 13 samples). in total 469 samples were collected from National Institute of Animal Science (Korean Native Chicken (NR, NY, NG, NL and NW), Ogye (NO), Leghorn F,K (NF and NK), Black and Brown cormish (NH and NS), Rhode Island Red C, D (NC and ND), Total is 12 populations] and Hanhyup [H line (HH), F line (HF), G line (HG), V line (HV), S line (HS), W line (HW), Y line (HY), A line (HA), total is 8 populations]. [The allele number were observed 5 (ADL0268) to 20 (MCW0127) each markers. Observed heterozygostiy ($H_{obs}$), expected heterozygosity ($H_{exp}$), polymorphism Information Content (PIC) were observed 0.359 to 0.677, 0.668 to 0.881 and 0.646 to 0.869, respectively. Using these markers, the calculated the heterozygote deficit within chicken line ($F_{is}$) value each population from mean 0.117. Phylogenetic tree showing the genetic relationship among 20 population using standard genetic distance calculated from 27 microsatellite markers. genetic distances revealed the closest (0.175) between NC and ND. on the other hand, Farthest genetic distances (0.710) revealed between NF and HV. STRUCTURE analysis and Principal Components Analysis (PCA) showed that results of similar phylogenetic tree. The expected probability of identity values on random individuals (Total population and only Hanhyup line) was estimated at $8.80{\times}10^{-83}$ and $3.87{\times}10^{-117}$, respectively. In conclusion, This study shows the useful data that be utilized as a basic data of Korean Native Chicken breeding and development for commercial chicken industry to meet the consumer's demand.

The relationship between students' perceptions and practicability of the "Me and My Family Relations" unit and Family strength among middle school students (나와 가족관계' 단원에 대한 중학생의 긍정적 인식, 실천성 인식과 가족건강성)

  • Cho, Byung-Eun;Jung, Sun-Hee
    • Journal of Korean Home Economics Education Association
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    • v.19 no.1 s.43
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    • pp.99-114
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    • 2007
  • This study aims at investigating how middle school students perceive the content of the 'Me and My Family Relations' unit in the technology and home economics textbook, act on such perceptions and how this connects with their healthy family relations. In addition, the study also points at inquiring into what kind of differences and mutual influences can be found in the above-mentioned three factors according to family environment. With this objective. this research has analyzed survey data conducted on 401 7th grade middle school students residing in Incheon Greater city, collected by the random sampling method. The findings are as follow: First, the students were found to have positive perceptions on the 'family relations and communication' unit in the technology and home economics text book. However. they were also found to perceive that the content was not as realizable in their everyday family lives. Second, the number of students who perceived their family lives to be healthy was found to be quite high. The students perceived their family lives to be healthy projecting from such aspects as the degree of gratification and affection, extent of family bonding, communication patterns, and problem solving abilities, in the same order. In addition, the higher the families' socio-economic level, and in the cases that the students had working mothers and the fathers held higher degrees, the degree to which the families were perceived to be healthy was higher. Third, in investigating the influence that such factors as the students' family environment, the degree that students perceived the text book content positively, and the degree that the students perceive the content to be realizable have on healthy family relations, among these factors, the students' perceived degree of how healthy their family relations are had the most bearing over the above-mentioned factors. The second influential factor on how healthy family relations are was the family's affectional environment, found to be more influential than such factors as family type, the mother's employment status, living standards, and the parents' educational level. On the other hand, the perceived level of realizability was found to have a lower influence on the students' family relations than the perceived positivity.

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Vitamin D and Risk of Respiratory Tract Infections in Children: A Systematic Review and Meta-analysis of Randomized Controlled Trials (비타민 D와 소아 호흡기 감염의 위험성: 무작위 대조 연구에 대한 체계적 문헌고찰 및 메타분석)

  • Ahn, Jong Gyun;Lee, Dokyung;Kim, Kyung-Hyo
    • Pediatric Infection and Vaccine
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    • v.23 no.2
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    • pp.109-116
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    • 2016
  • Purpose: Recent observational studies have found that vitamin D deficiency is associated with respiratory tract infections. However, randomized controlled trials (RCTs) regarding the efficacy of vitamin D in childhood respiratory tract infection (RTI) have yield inconsistent results. We performed a systematic review and meta-analysis to evaluate the association between vitamin D supplementation and the risk of RTI. Methods: A comprehensive search was conducted using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trial. Randomized controlled trials of vitamin D supplementation for prevention of RTI in children were included for the analysis. Cochrane Collaboration's tool for assessing the risk of bias was used to assess the quality of the studies. Pooled risk ratios with 95% confidence intervals (CIs) were meta-analyzed using Review Manager 5.3. Results: A total of seven RCTs were included in the meta-analysis. According to a random-effects model, the risk ratio for vitamin D supplementation was 0.82 (95% CI: 0.69-0.98) and $I^2=62%$ for heterogeneity. On subgroup analysis, heterogeneity decreased in the subgroup with follow-up less than 1 year, participants ${\geq}5years$ of age, patients subgroup, and subgroup with dosing daily. Funnel plot showed that there might be publication bias in the field. Conclusions: The present meta-analysis supports a beneficial effect of vitamin D supplementation for the prevention of RTI in children. However, the result should be interpreted with caution due to limitations including a small number of available RCTs, heterogeneity among the studies, and potential publication bias.

A study on the status of the Dental Health of Adults (일 지역 성인의 구강건강실태에 관한 조사연구)

  • 정영숙
    • Korean Journal of Health Education and Promotion
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    • v.17 no.1
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    • pp.95-113
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    • 2000
  • The purpose of this study is to investigate the state of the dental health of adults, used self-reporting qestionnaire as objects of 923 residents living in nine districts at random among the sites of eleven town located in a County. The level of knowledge on dental health of adults in a County was 65.6 points out of 100 points, comparatively low. Accodingly, it is necessary for entire adults to have a dental health-related education and get high standard of knowledge. Especially, educational approach should be performed for groups of 40-49 years old, 50-59 years old, above 60 years old, male, no educational background, having only elementary and middle school education, not having any jobs, engaging in agriculture, doing business on their own and so on. When planning the contents of health education, one actually has to include the habit of amalgam, the factor in influencing on dental health as well as show an example such as how to brush teeth, checking point of proper brushing, how to grip toothbrush. The attitude score related to dental heath was 71.2 points out of 100 points, relatively low. Consequently, the change of attitude related the dental health among entire adults is necessary, particularily, the strategical approach is essential to change dental health connected to attitude positively for groups of male, having high school education background, office workers and the civil service. Besides, among dental health related symtoms, more that 30-40% of objects showed negative attitude toward as the following cases; in case that plaque or food debris are attached to the teeth (40.8%), upper and lower teeth do not fit together(40.3%), you cannot sleep well because of toothache(31.0%), more than one tooth fall out(31.0%), you have loosing teeth(30.6%), the approach should be conducted to form attitude that dental care is necessry. The state of dental health through dental health related symtoms was 33.3 points out of 100 points, which was fairly satisfactory. However, dental treatment for the state of dental health should be executed in case of comparison of the dental health state according to general characteristics, the group who are above 60 years old, have elementary school education background, engage in aggriculture who are not good in dental health state as opposed to other groups. Furthermore, there should be dental care needs according to dental health related symtoms, particularly, more than 60-70% of objects have experienced symtoms that plaque or food debris attached to the teeth, tartar is on the teeth so dental treatment should be peformed for a large number of adults. In addition, for the people who have indications that there was a cavity, more than one tooth loss, chilled teeth, toothache when chewing, loose teeth, upper and lower teeth do not fit together, you cannnt sleep well due to the toothach, etc, there should be care through dental treatment. The actual conditions of the hygine of the mouth was relatively good and the difference of the actual state of dental health care in terms of general characteristics showed in only gender; female was more careful in dental health. Comparing the state of oral health synthetically, when they have symtoms, only 34.8% of objects go to a dentist, 60.7% are using passive or negative care such as gargling, tolerating or ignoring. There was many symtoms to care through dental therapy such as plaque or food debris get in between the teeth, tartar on the teeth, teeth are very cold, more than one tooth fallout, loose teeth, there is wrong amalgam, and so on, among symtoms to care passively or negatively. Therefore the education for proper treatment program should be performed. As a result of dental health-related knowlege, attitude, health state, verification of correlation between the actual condition of care, the higher the dental heath-related knowldege becomes, the more positive the dental health-related attitude is, and the state of dental health, that is, the standard of the symtom of dental health diminishes. the care for dental health executed through more active method and the more positive dental health-related attitude is, the more active means they performed. Consequently, the high level of dental health-related knowledge should be necessary, the more positive the dental health-related attitude was, the more active method they adopted, therefore, the program is needed to form attitude related to the dental health positively. As the knowledge on dental health is increasing, the attitude is also positive, after all, the plan to increase the standard of knowledge on dental health should be contrived through education program related to dental health.

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Analysis of Microsatellite DNA Polymorphism for Parentage Testing in Dog Breeds (개의 친자감정을 위한 Microsatellite DNA 다형성 분석)

  • Cho, G. J.;Cho, B. W.;Kim, S. K.;Lee, K. W.;Kim, Y. K.
    • Journal of Animal Science and Technology
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    • v.45 no.2
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    • pp.191-198
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    • 2003
  • This study was carried out to investigate a usefulness of the microsatellite DNA markers for individual identification and parentage verification in three dog breeds. A total of 59 random dog (31 Chiwawa, 20 Poongsan, 8 Labrador Retriever) samples were genotyped by using 14 markers (Chiwawa dog), 16 markers (Poongsan dog), and 12 markers (Labrador Retriever dog) among the 17 international standard markers (PEZ1, 3, 5, 6, 8, 10, 11, 12, 13, 15, 16, 17, 20, 21, FHC2010, FHC2054 and FHC2079), respectively. The number of alleles per locus varied from 4 to 14 with a mean value of 6.07 in Chiwawa dog, 2 to 9 with a mean of 4.75 in Poongsan dog, and 3 to 5 with a mean of 4.00 in Labrador Retriever dog. Observed heterozygosity was ranged 0.419${\sim}$0.968 (mean 0.755), 0.300${\sim}$0.950 (mean 0.597) and 0.125${\sim}$0.750 (mean 0.604), and expected heterozygosity was ranged 0.432${\sim}$0.883 (mean 0.711), 0.262${\sim}$0.817 (mean 0.559) and 0.425${\sim}$0.808 (mean 0.660) in these three dog breeds. PIC value was ranged 0.397${\sim}$0.856 (mean 0.659), 0.222${\sim}$0.772 (mean 0.503) and 0.354${\sim}$0.717 (mean 0.563) in these three dog breeds. Of the 17 markers, PEZ1, PEZ3, PEZ6, PEZ10, PEZ12 loci, PEZ1, PEZ6, PEZ13 loci, and PEZ8, PEZ12 loci have relatively high PIC value (>0.7) in Chiwawa dog, Poongsan dog and Labrador Retriever dog, respectively. The exclusion probability was ranged 0.240${\sim}$0.741, 0.111${\sim}$0.616, and 0.198${\sim}$0.529, and the combination of microsatellite loci was 0.9999, 0.9991, and 0.9968 in Chiwawa dog, Poongsan dog and Labrador Retriever dog, respectively. These results can give basic information for developing parentage verification and individual identification system in these three dog breeds.

A Web-based 'Patterns of Care Study' System for Clinical Radiation Oncology in Korea: Development, Launching, and Characteristics (우리나라 임상방사선종양을 위한 웹 기반 PCS 시스템의 개발과 특성)

  • Kim, Il Han;Chie, Eui Kyu;Oh, Do Hoon;Suh Chang-Ok;Kim, Jong Hoon;Ahn, Yong Chan;Hur, Won-Joo;Chung, Woong Ki;Choi, Doo Ho;Lee, Jae Won
    • Radiation Oncology Journal
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    • v.21 no.4
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    • pp.291-298
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    • 2003
  • Purpose: We report upon a web-based system for Patterns of Care Study (PCS) devised for Korean radiation oncology. This PCS was designed to establish standard tools for clinical quality assurance, to determine basic parameters for radiation oncology processes, to offer a solid system for cooperative clinical studies and a useful standard database for comparisons with other national databases. Materials and Methods: The system consisted of a main server with two back-ups in other locations. The program uses a Linux operating system and a MySQL database. Cancers with high frequencies in radiotherapy departments in Korea from 1998 to 1999 were chosen to have a developmental priority. Results: The web-based clinical PCS .system for radiotherapy in www.pcs.re.kr was developed in early 2003 for cancers of the breast, rectum, esophagus, larynx and lung, and for brain metastasis. The total number of PCS study items exceeded one thousand. Our PCS system features user-friendliness, double entry checking, data security, encryption, hard disc mirroring, double back-up, and statistical analysis. Alphanumeric data can be input as well as image data. In addition, programs were constructed for IRB submission, random sampling of data, and departmental structure. Conclusion: For the first time in the field of PCS, we have developed a web-based system and associated working programs. With this system, we can gather sample data in a short period and thus save, cost, effort and time. Data audits should be peformed to validate input data. We propose that this system should be considered as a standard method for PCS or similar types of data collection systems.

A Study of Health Condion and Shift Service of the Nurse in (종합병원 간호사의 교대근무와 건강상태에 관한 연구)

  • Kim, Soon-Ok
    • Journal of Korean Academy of Nursing Administration
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    • v.3 no.1
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    • pp.119-133
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    • 1997
  • Continuing shift service of clinical nurses can be not only the cause of occupational dissatisfaction by being connected with the change of circadian rhythm and the burden of duties to be applicable to such changes. But also of inviting the lowering of nursing quality by being affected to the resignation of the nurses as the threat to the health of the nurses. This study has selected 500 nurses at random under non-probability sampling who have been serving by shift in 7 general hospitals which have over 400 sickbeds for the purpose of cross-sectional survey design from Sep. 7 through 20, 1996. Standardized modification of the CMI has been used which was designed for Koreans with Cornell Medical Index developed by Broadman and his fellow workers as the study device. The structure of the device was composed of 35 questions on physical appeal(Chronbach's ${\alpha}=8507$) and 22 questions of mental appeal(Cronbach's ${\alpha}=.8166$ totalling 57 questions. The collected data has been computerrized by using SPSS. General character, present symptom, perceived symptom and others are sought by practical number and percentage, and the health condition comparison followed by general characters was conducted by t-test and ANOVA. The post test was by Duncan's test by the level of p<.05. 1) The items of the answer that they have the physical symptom presently by 50% or over of the nurses were as "Do you often have spells of severe dizziness", "Are your eyes often red or inflamed", "Does press or pain in the head often make like miserable", "Are your ankles often badly swollen", "Do pains in the back make it hard for you to keep up with your work". 2) The items of the answer by over 50% of the nurses as the mental symptom at present were "do you fell bad when criticized?", "Do you get angry when everything is against your will?", "do you get angry when ordered to do this and that?", "do you feel uneasy by such a trifle thing?", "do you tremble or are you freightened by sudden sound?". The mental and physical symptoms which have appeared presently in connection with the shift service have been agreed with each other. But the physical condition has been worse than the mental one. 3) In the physical health conditions followed by demosociological character, there were the significant differences by sex, religion and place of residence(p<.05), and in the mental health conditions, there were the significant differences by age, marital status, residence place and the required time for attending hospital(p<.05). 4) There was significant difference by the degree of satisfaction about the duty in both the physical and mental health conditions. In short, the higher the degree of duty satisfaction, the better the health conditions. 5) There were the significant difference according to the times of night duty and whether they take the drug or not or the kinds of the drugs in the physical health conditions related with the characters of night shift. Mental health conditions in the night shift case showed significant differences according to their taking drug or not or the kinds of the drugs(p<.05). I can confirm that the nurses have been affected continuously by the shift service mentally and physically. The maintenance of the physical and mental health of the nurses and its promotion are very important problem to guarantee the quality nursing in the performance of the nursing service continuously and effectively, so the hospital should make every effort to improve the duty conditions by finding out the causes affecting to their health. In the nursing management viewpoint, I think that elevating the satisfaction degree about the duty would be a great help to the promotion of physical and mental health conditions. But what is most important is that the nurses themselves should take care of themselves in maintaining the good conditions in their service in the hospital.

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Increasing Accuracy of Stock Price Pattern Prediction through Data Augmentation for Deep Learning (데이터 증강을 통한 딥러닝 기반 주가 패턴 예측 정확도 향상 방안)

  • Kim, Youngjun;Kim, Yeojeong;Lee, Insun;Lee, Hong Joo
    • The Journal of Bigdata
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    • v.4 no.2
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    • pp.1-12
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    • 2019
  • As Artificial Intelligence (AI) technology develops, it is applied to various fields such as image, voice, and text. AI has shown fine results in certain areas. Researchers have tried to predict the stock market by utilizing artificial intelligence as well. Predicting the stock market is known as one of the difficult problems since the stock market is affected by various factors such as economy and politics. In the field of AI, there are attempts to predict the ups and downs of stock price by studying stock price patterns using various machine learning techniques. This study suggest a way of predicting stock price patterns based on the Convolutional Neural Network(CNN) among machine learning techniques. CNN uses neural networks to classify images by extracting features from images through convolutional layers. Therefore, this study tries to classify candlestick images made by stock data in order to predict patterns. This study has two objectives. The first one referred as Case 1 is to predict the patterns with the images made by the same-day stock price data. The second one referred as Case 2 is to predict the next day stock price patterns with the images produced by the daily stock price data. In Case 1, data augmentation methods - random modification and Gaussian noise - are applied to generate more training data, and the generated images are put into the model to fit. Given that deep learning requires a large amount of data, this study suggests a method of data augmentation for candlestick images. Also, this study compares the accuracies of the images with Gaussian noise and different classification problems. All data in this study is collected through OpenAPI provided by DaiShin Securities. Case 1 has five different labels depending on patterns. The patterns are up with up closing, up with down closing, down with up closing, down with down closing, and staying. The images in Case 1 are created by removing the last candle(-1candle), the last two candles(-2candles), and the last three candles(-3candles) from 60 minutes, 30 minutes, 10 minutes, and 5 minutes candle charts. 60 minutes candle chart means one candle in the image has 60 minutes of information containing an open price, high price, low price, close price. Case 2 has two labels that are up and down. This study for Case 2 has generated for 60 minutes, 30 minutes, 10 minutes, and 5minutes candle charts without removing any candle. Considering the stock data, moving the candles in the images is suggested, instead of existing data augmentation techniques. How much the candles are moved is defined as the modified value. The average difference of closing prices between candles was 0.0029. Therefore, in this study, 0.003, 0.002, 0.001, 0.00025 are used for the modified value. The number of images was doubled after data augmentation. When it comes to Gaussian Noise, the mean value was 0, and the value of variance was 0.01. For both Case 1 and Case 2, the model is based on VGG-Net16 that has 16 layers. As a result, 10 minutes -1candle showed the best accuracy among 60 minutes, 30 minutes, 10 minutes, 5minutes candle charts. Thus, 10 minutes images were utilized for the rest of the experiment in Case 1. The three candles removed from the images were selected for data augmentation and application of Gaussian noise. 10 minutes -3candle resulted in 79.72% accuracy. The accuracy of the images with 0.00025 modified value and 100% changed candles was 79.92%. Applying Gaussian noise helped the accuracy to be 80.98%. According to the outcomes of Case 2, 60minutes candle charts could predict patterns of tomorrow by 82.60%. To sum up, this study is expected to contribute to further studies on the prediction of stock price patterns using images. This research provides a possible method for data augmentation of stock data.

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