• Title/Summary/Keyword: Statistical power

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Effect of field location and spray device on pesticide residue in chilli peppers (농약 살포조건이 고추열매 중 잔류에 미치는 영향)

  • Son, Kyeong-Ae;Kang, Tae-Kyeong;Park, Byeong-Jun;Kim, Taek-Kyum;Gil, Geun-Hwan;Kim, Chan-Sub;Kim, Jin-Bae;Im, Geon-Jae;Lee, Key-Woon
    • The Korean Journal of Pesticide Science
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    • v.16 no.3
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    • pp.230-235
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    • 2012
  • This study was carried out to clarify effects of field location and sprayer on the level of pesticide residue in chilli peppers. As confirmed by statistical analysis, the residue levels in green pepper among three greenhouses did not show significant difference at the first day after spraying with the same engine sprayer and nozzle. But the residue levels in green peppers collected from the exposed outside of crop were 2 times higher than those from the hidden inside. The sampling site was one of variation elements of pesticide residue. The residue levels after application by knapsack engine powered sprayer were 1.7 times higher than those by manual compressed sprayer. As the spraying pressure of the engine power sprayer is 2 times higher than the commonly used pressure of the manual compressed sprayer, the pressure of the sprayer and nozzles were considered to affect on the residue levels in peppers.

Comparing Survival Functions with Doubly Interval-Censored Data: An Application to Diabetes Surveyed by Korean Cancer Prevention Study (이중구간중도절단된 생존자료의 생존함수 비교를 위한 검정: 한국인 암 예방연구 중 당뇨병에의 응용)

  • Jee, Sun-Ha;Nam, Chung-Mo;Kim, Jin-Heum
    • The Korean Journal of Applied Statistics
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    • v.22 no.3
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    • pp.595-606
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    • 2009
  • Two tests were introduced for comparing several survival functions with doubly interval-censored data and illustrated with data surveyed by Korean Cancer Prevention Study (Jee et al., 2005). The test which extended Kim et al. (2006)'s test to the doubly interval-censored data has an advantage over Sun (2006)'s test in terms of saving computation time because the proposed test only depends on the size of risk set, and also the proposed test is applicable to continuous failure time data as well as discrete failure time data unlike Sun's test. Comparing male with female groups on the incubation time of diabetes was highly different and the survival of female group was longer than that of male one. Regardless of gender, the difference in survival functions of four age groups was highly significant with p-value of less than 0.001. This trend was more remarkable for female group than for male one. Simulation results showed that the significance level of both tests was well controlled and the proposed test was better than Sun's test in terms of power.

Effect of Naeso-san on Gastric Motility between Normal Intact and Antral Dilatated Rats (내소산(內消散)의 정상 및 위 유문부 확장 흰 쥐의 위 운동성에 대한 효능)

  • Kim, Jin-Seok;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.29 no.1
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    • pp.117-129
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    • 2008
  • Background & Objective : Naeso-san(NSS) has been used for the treatment of functional dyspepsia, regarded as a gastric dysmotility disease. A main cause of gastric dysmotility is antral dilatation or antroduodenal uncoordination. Therefore, we investigated the effect of NSS on gastric motility and its mechanism of action, as well as the morphologic changes in antral dilatated rats. Methods : Antral dilatated rats were induced by wrapping a nonabsorbable rubber ring(D:6mm, W:4mm, T:1mm) around the 1st portion of the duodenum for 8 weeks. Then morphologic changes were investigated and compared with normal intact rats before and after 8 weeks. Gastric emptying was measured by administration of normal saline(NS) or NSS in normal intact and antral dilatated rats. In another series of experiments to evaluate the mechanism of NSS under delayed conditions, normal intact rats were treated with atropine sulfate(1mg/kg, s.c.), quinpirole HCl(0.3mg/kg, i.p.), $NAME(N^{G}-nitro-L-arginine$ methyl ester, 75mg/kg, s.c.) and cisplatin(10mg/kg, i.p.), respectively. The myoelectrical activity of the gastric smooth muscle was recorded in normal intact and antral dilatated rats. The contractile waves were measured for 30 minutes before and after administration of each solution(NS, NSS). Results : Body weight gain of antral dilatated rats was significantly lower than that of the controls. Futhermore, we found the thickness of the mucosal and muscular layers and surface area of the stomach increased significantly compared with controls. NSS 278㎎/㎏ improved gastric emptying more than normal saline or NSS 93mg/kg in normal intact(p=0.026) and antral dilatated rats(p=0.03). NSS enhanced gastric emptying significantly in the NAME treated group(p=0.002). NSS 278mg/kg increased the significant postprandial dominant power than that of NS in normal intact rats, whereas there was no statistical significance in antral dilatated rats. Conclusions : NSS stimulates gastric motility through the cholinergic pathway. We expect that pathologic model with antral dilatation can be used as an exprimental tool which is similar to dyspepsia and NSS would be effective especially in dysmotility-like functional dyspepsia with antral dilatation or impaired reservoir functions such as gastric adaptive relaxation.

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Risk Factors of Work-related Low Back Pain in Manufacturing Workers (제조업 근로자들의 작업과 연관된 요통의 위험요인에 관한 연구)

  • Kim, D.H.;Shin, H.R.;Chun, J.H.;Kim, Y.W.;Kim, J.H.;Lee, C.U.
    • Journal of Preventive Medicine and Public Health
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    • v.26 no.1 s.41
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    • pp.20-36
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    • 1993
  • Work-related low back pain is one of the major factors that cause the loss of working power especially in actively working age, therefore controlling the work-related low back pain is one of the major issues in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the efficient control program of the work-related low back pain. The subjects were male workers employed at the manufacturing industry in Pusan with longer than 6 months' working duration. The data was collected by self-reported questionnaire and interview from May 1 to October 31,1992. The contents of questionnaire were as follows:. the experience of low back pain within the recent one month, general characteristics(age, marital status, education level, religion, regular exercise), physical characteristics(height, weight), employment status(working duration, daily working hours, rest during work, satis(action fur the job), type of work and working environments(posture, forward bending, lifting and movement, satisfaction for table and chair). The result was analyzed for 608 entire respondents by case-control comparative method. The number of cases was 152 with a history of work-related low back pain, so the relative frequency of self-reported work-related low back pain was 25.0%, and the number of controls was 344 without any history of low back pain. As a result, two characteristics of the employment status(working duration, satisfaction fur the job) and all characteristics of type of work and working environments showed a statistical significance between the case and control groups(p<0.01). The Oddb ratios of these variables for Work-related low back pain were calculated. They were 7.88 for the satisfaction fur chair, 7.86 for lifting and movement,3.31 for satisfaction for table, and 2.22 fur bending forward(p<0.01). And for the multivariate logistic regression analysis confirmed that unsatisfaction for table was independent risk factor for Work-related low back pain. In summary, though this study was based upon the self-reported questionnaire and the subjective complaints, the satisfaction for chair, lifting and movement, satisfaction for table, and bending forward concerned with the type of work and working environments were considered as the main factors causing the work-related low back pain, and the work-related low back pain may be preventable by the ergonomic control of these factors.

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The Impact of Competitive Environments on the Configuration of e-Biz Integration Determinants and the Business Performance (경쟁적 환경이 e-Biz통합의 결정요인 구성과 경영성과에 미치는 영향)

  • Han, Bong-Ho;Kim, Chul-Soo;Seo, Chang-Soo
    • Asia pacific journal of information systems
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    • v.21 no.2
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    • pp.59-87
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    • 2011
  • These days, firms are focusing on the improvement of relationships with business partners. The supply chain integrations are taking critical role in improving the relationships with business partners. In accordance with the development of the IT technology, it became possible for firms not only to integrate inner parts of the organization, but also to integrate the company with other organizations in the supply chain. Therefore, in e-Biz environments, it is imperative for firms to strengthen the core capacity through the supply chain, and to precisely determine the components of the determinants of e-Business integration which impact the firm performance. This study analyzed determinants that have impacts on e-business integration in e-business capacity perspectives in competitive environments. This study based on the premise that the resources and capacities that Grant(1991) and Hart(1995) emphasized do not directly influence the corporate performance. This study focused on the fact that corporate must create core competencies based on these capacities to establish competitive edge. Therefore, this study model analyzed to find out which e-Biz competencies are needed to integrate e-Biz according to competitive environment elements. This study designed to empirically analyze the impact of the e-Biz competencies to the e-Biz integration and to the corporate performance. Independent variables of this study-IT management, partner management, e-Biz knowledge, e-Biz establishment and proliferation, process innovation-are selected based on precedent studies on e-Biz competencies. We selected intermediate variables to verify that e-Biz competencies do not have direct impact on the corporate performance, but have impact on the e-Biz integration, which is intermediate effect. That is to verify that if the components of supply chain improve the integration level using e-Biz competencies, the overall supply chain performances will improve. Dependent variables are selected to verify that e-Biz integration has impacts on corporate performances. This study used factor analysis, path analysis, moderating effect analysis as statistical tests. First, we used exploratory factor analysis and confirmatory factor analysis to analyze reliability and validity. Because e-Biz competencies are presented variously by preceding studies, we used SPSS16.0 to verify if survey questionnaire used by theoretical backgrounds is properly composed. Second, we tested the property of structure model by AMOS. We did path analysis using AMOS16.0 to test structure that is composed of e-Biz competencies and e-Biz integration. Last, we tested moderating effects of measure factors. We analyzed 163 domestic companies to find out many significant suggestive points. First, relationship improvement capacity, e-business knowledge sharing capacity with business partners, and process innovation capacity are adopted as determinants of differentiation and competitive edges against competing firms. Second, e-business knowledge sharing capacity, and process innovation capacity are analyzed as the determinants of e-business integration in the firm which demand fluctuation in the market is high. On the other hand, among the determinants that require capturing ideas on new products, and strengthening the technological power, process innovation capacity are adopted as the determinants. These results provide us the foundation that the determinants that we have analyzed can impact the supply chain integration strategies which take into account the competitive environments.

Study about the Association between Diabetes and the Targeted SNPs of TCF7L2 and FTO Genes (당뇨병에서 TCF7L2와 FTO 유전자의 특정 단일염기다형성과의 연관성 연구)

  • Hsia, Yu-Chun;Park, Jong-Hyung;Jun, Chan-Yong;Ko, Seung-Gyu;Choi, You-Kyung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.3
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    • pp.504-511
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    • 2010
  • Diabetes is a disease that contains a high concentration of glucose in blood and due to defects in either insulin secretion or insulin action. Although the distinctive causes and factors of diabetes have not been clarified, the genetic factors are suggested as a main susceptibility until now. SNP (Single Nucleotide Polymorphism), as the most common genetic variation, has an influence on personal susceptibility for diseases. A nonsynonymous SNP, which changes the amino acid of the protein and its function, is especially important. Therefore, this study hypothesized that there are associations between specific SNPs of the targeted genes. Transcription factor 7-like 2 (TCF7L2) and fat mass and obesity associated (FTO) genes were selected as target genes from the results of genome-wide association and other related research studies. Second, four nonsynonymous SNPs (three in TCF7L2 and one in FTO gene) were selected as target SNPs by using public database of NCBI (National Center for Biotechnology Information). The recruited personnel was classified into three subgroups of diabetes, impaired fasting glucose (IFG) and normal groups. The individual genotypes of each group were analyzed by resequencing. None of genetic variations at four targeted SNP sites was revealed in all samples of this study. However, this study found two new SNPs that were not reported in TCF7L2 gene. One is synonymous SNP, which is heterozygous of C/T and no amino acid change of asparagine/asparagines, was located at c1641 and found in one normal person. Another is nonsynonymous SNP, which is heterozygous of G/A, was located at c1501 and found in two samples. This new discovered nonsynonymous SNP induce the amino acid change from alanine to threonine. Moreover, this new nonsynonymous SNP was found among two persons, one of whom was a diabetes patient and the other one was a person at boundary between IFG and normal, suggesting that this variant might be associated with IFG or diabetes. Even if there is a limitation of sample number for statistical power, this study has an importance due to the discovery of new SNPs. In the future study, a large sample number of diabetes cohort will be needed to investigate the frequency and association with new discovered SNP.

Forecast study for active factor of V2B(Vehicle to Building) operation zero energy building using monte carlo method (몬테카를로방법을 이용한 V2B(Vehicle to Building) 운용 제로에너지빌딩의 액티브 요소 예측 연구)

  • Kim, Youngil;Kim, Insoo
    • Journal of Energy Engineering
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    • v.26 no.4
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    • pp.29-34
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    • 2017
  • Factors of Zero-Energy Building are divided into active and passive factor. Passive factor means insulation, heat bridge of building like insulation, windows and doors, awning, outside etc. and active factor means energy output and efficiency coefficient. Energy output of active factor is achieved by new generating energy. This study anticipated how many effects will be produced when not new generating energy but Vehicle to Building; V2B, bi-directional charging and discharging technology, is applied to Zero-Energy Building. In new generating energy, power generation will be anticipated by geography and climate, but in V2B, several input variable like user's discharging intention and number of usable charger etc. should be considered. We can check how much V2B contribute to the Zero-Energy Building by anticipated results, and that results should be anticipated by using probabilitic method because there is few statistical data. This study anticipate change of charging and discharging pattern, based by Demand Response slot, by using monte carlo method among the probabilitic methods.

A Study on Grade Comparison Difference Analysis of the Gifted Children in IT (정보영재아동의 학년별 차이 비교 분석에 관한 연구)

  • Jun, Woochun;Hong, Suk-Ki
    • Journal of Internet Computing and Services
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    • v.15 no.5
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    • pp.25-32
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    • 2014
  • In the current information and knowledge-based society, a nation's economy power heavily depends on IT-related industry and technology. In this sense, most countries are trying to foster IT industry by developing new and innovative IT technologies. Traditionally, only a few talented persons have been leading the whole IT industry. Thus, it is very important and necessary to identify and support the gifted children in IT in early ages for development of IT industry. The purpose of this paper is to investigate study performance of the gifted children in IT for different grades. Our research is focused on especially 4th grade students, 5th grade students, and 6th grade students in elementary schools. Among various abilities of the gifted children in IT, in this paper, we are interested in programming ability and logical thinking ability. To our best knowledge, there is no research work on study performance depending on different grades of the gifted children in IT. For this purpose, the gifted students in gifted science education center attached in a university at Seoul Metropolitan Area are selected and their test scores for 8 years were collected and analyzed. The statistical analysis results show that there is no significant difference among 4th grade students, 5th grade students, and 6th grade students for programming ability and logical thinking ability. We hope that this result can help suggest and propose study contents, curriculum, principles and laws for the gifted education in IT.

Study on analysis of the Corporate requirements and CPND Value chain for e-book Market Activation (전자책 시장 활성화를 위한 기업 요구사항과 CPND 가치사슬 분석)

  • Na, Yun-Bin;Yu, Jong-Sun;Lee, Seoung-Ha
    • Journal of Digital Convergence
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    • v.14 no.4
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    • pp.163-171
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    • 2016
  • This study derived the policy implications and market strategies by analysis the e-book companies requirements & the CPND value chain structure, in order to revitalize the e-book market in Korea. Specifically, we examined the prospect of e-book market in Korea, current situations of production and distribution, awareness of service utilization and requirements for support policy with targets of 30 companies. As a research, the most needed item for e-book companies is 'PR and marketing support to enter and open the markets'(27%), which is the highest. 'Financial support such as labor costs and business expenses', 'support for retraining personnel to develop the expertise in respective fields' are followed and they account for 22%. Currently, the most effective support item is the external support program(35%) and funding power(30%) is followed. Unlike a paper book market, e-book is turned into a platform business in terms of the value chain. Based on these research content, e-book market activation and corporate competitive strategy was derived as follows : 1)literacy reinforcement about SNS marketing and e-pub3 authoring tool. 2)statistical DB construction of retail sales channels. 3)diversification of the billing system. 4)The quality of the e-book content certification.

A study of the psychosomatic self-reported symptoms of the dental technology students (치기공과 재학생의 건강관련 심신 자각증상에 관한 연구)

  • Kwon, Soon-Suk
    • Journal of Technologic Dentistry
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    • v.35 no.2
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    • pp.157-171
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    • 2013
  • Purpose: This study aims to present a database for the development of a healthcare management program based on the survey and analysis of self reported psychosomatic symptoms among the current dental technology students. Methods: Subjects of our study are 480 dental technology major students enrolled in a third year college located Gyeonggi, Chungcheong, and Gangwon province. Using a random sampling, we conducted a self-report survey from August 30, 2011 to October 28, 2011 and 418 reports were collected as feedback and we put an analysis on them. Results: 1. The average physical self symptom was 20.49, which is higher than the average mental self symptom(18.54). Of the subcategories of psychosomatic self symptom, we observed multiple subjective symptoms as the highest one(37.77), and aggression as the lowest(13.77). 2. As to gender, both physical and mental self symptom were statistically significant with the scale score of(p<.001). The scale score of subcategories is as follows; multiple subjective symptoms(I, p<.001), eye and skin(B, p<.001), digestive(C, p<.001), impulsiveness(H, p<.001), lie scale(L, p<.001), mental instability(J, p<.001), depression(K, p<.001), aggression(F, p<.001), irregularity of life(G, p<.001), mouth and anal(D, p<.05), nervousness(E, p<.05). 3. As for obesity, statistical significance was shown with the scale scores of physical self symptom(p<.001), multiple subjective symptoms(I, p<.001), digestive(C, p<.001), aggression(F, p<.001), depression(K, p<.01), irregularity of life(G, p<.01), respiratory(A, p<.05), eye and skin(B, p<.05), impulsiveness(H, p<.05), mental instability(J, p<.05). The scale scores in the environmental quality and life satisfaction were shown as follows; depression(K, p<.001), lie scale(L, p<.01), and irregularity of life(G, p<.05). 4. We employed multiple regression analysis to take account of general factors affecting psychosomatic self symptoms, and drew that the explanatory power of the model was proved with the scales of physical self symptom(4.1%) and mental self-symptom(3.6%). Obesity was a factor that affects physical self symptom with the scale score of(p<.01), and environmental quality and life satisfaction(p<.01) and obesity(p<.05) affect mental self symptom. Conclusion: In this analysis we observed obesity of dental technology students can influence their psychosomatic self symptoms. In this sense, it would be reasonable to develop a healthcare management and education programs that help the students maintain a healthy weight and promote their health.