• 제목/요약/키워드: significance verification

검색결과 226건 처리시간 0.024초

능동포집법과 확산포집법에 의한 작업환경 중 포름알데히드 농도 비교 (Comparison of formaldehyde concentration in working environment between passive sampling method and impinger sampling method)

  • 함성애;문덕환
    • 한국산업보건학회지
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    • 제16권4호
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    • pp.346-355
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    • 2006
  • The purpose of this study was conducted to ascertain the difference between impinger and passive sampling methods in the process of sampling and analyzing on airborne formaldehyde. Formaldehyde generating workplaces included in this study comprised four types of manufacturing industry such as two workplaces of products of wood, cork, straw and plaiting materials manufacturing industries, one casting metal manufacturing industry, and one parts and accessories for motor vehicles and it′s engines manufacturing industry. Workplaces contained in this study were located in some manufacturing area of Busan industrial complex and this study was carried out during a period from January 2003 to December 2004. Analytical accuracy, precision and detection limit of two methods was compared. Exposure level of its airborne concentration was evaluated in formaldehyde generating workplaces those were classified by types of industry, working process, and time. The results were as follows ; 1. A rate of recovery was 107.1% in impinger method and 101.8% in passive method, and precision was 7.79% in impinger method and 4.40% in passive method. There was no statistical significance in analytical accuracy and precision between two methods. A limitation of detection was 0.011 ppm in passive method which was lower than that of impinger method (0.020 ppm) by 1.8 times. 2. Airborne formaldehyde concentration of impinger method was different from passive method. It′s concentration by passive method was higher by 5.1 times than that by impinger method in the parts and accessories for motor vehicles and it′s engines manufacturing industry (P<0.05). Only in molding process among several types of processes, formaldehyde concentration in passive method was higher by 5.1 times than that in impinger method (P<0.05). Furthermore, formaldehyde concentration in passive method was higher by 1.7 times than that in impinger method (P<0.05) in the first half of year 2003. 3. The geometric mean of formaldehyde concentration in impinger method was lower than that in passive method, but there was no statistical significance of formaldehyde concentration by the difference of sampling method. In conclusion, it is difficult to conclude which is better between the two sampling methods because of no statistical significance for the difference of concentration. Because of lacks of certified passive sampling and analytical method, at present situation, studies on verification of accuracy and precision, obstructive reaction against validity on its exposure assessment, and research to develop domestically manufactured passive sampler in terms of cost-effectiveness should be continuously carried out.

Phylogenetic Analysis of the HIV-1 nef Gene from Korean Isolates

  • Lee, Dong-Hun;Yeup Yoon;Lee, Chan-Hee
    • Journal of Microbiology
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    • 제41권3호
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    • pp.232-238
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    • 2003
  • Previous phylogenetic studies on human immunodeficiency virus type 1 (HIV-1) isolated from Korean patients suggest that the major subtype of Korean isolate is subtype B. In this subtype, some of the Korean isolates seem to be clustered exclusively of foreign isolates. Presence of this so-called “Korean clade” among Korean isolates is unique but needs verification since the number of Korean isolates used in previous studies was limited. This study aimed to identify the presence of the “Korean clade” by molecular phylogenetic analysis using all the Korean nef gene sequences registered in the NCBI GenBank (N=243) together with 32 reference strains and 77 foreign isolates. Extensive analysis of the nef gene nucleotide sequences by neighbor-joining method revealed the following. Most (83.1 %) of the Korean isolates belonged to subtype B, and 81.2% of subtype B were clustered together and excluded foreign isolates (bootstrap value=91.9% ). Within Korean subtype B cluster, no characteristic subcluster formation was evident since the bootstrap values for the subcluster were very low. Due to limited information, the phylogenetic analysis failed to identify the epidemiological linkage among specific groups such as homosexuals and hemophiliacs within the Korean subtype B cluster. Detailed analysis and epidemiological information are needed to clarify the origin and significance of the Korean subtype B cluster.

검체검사 관련 법제도의 문제점 및 발전방향 (Problems and Developing Directions of the Legal System Related to Laboratory medical testing)

  • 황유성;정정일
    • 의료법학
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    • 제9권2호
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    • pp.209-229
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    • 2008
  • When we are totalizing the lawsrelated to the medical, as the Laboratory medical testing is a kind of the medical act, it is the regulation that the medical technologist can analyze the specimen using in vitro diagnostic devices and diagnosticdrugs under the guidance of doctor or dentist from a corresponding medical institution and can report through verification and interpretation. However, in real medical fields, 'the guidance of doctor' is seriously in-sufficient or even the person who is not the medical technologist is executing. Furthermore the cases that produce inspection results with devices or reagents which are not validated nor approved have been frequently occurred. The result of Laboratory medical testing derived from this procedure can become the important information for the disease control of a country, and also can be decisive to the definite diagnosis and the prognostic monitoring about the patient disease. In spite of its significant medical act to be applicable to an unique proof with the related expert appraisal result in the medical mal-practice lawsuit, our reality in which the quality control is not properly working due by the costs and the labor shortage related to the Laboratory medical testing is quietly in bad condition. Even from now, the government should recognize the significance of the Laboratory medical testing and must achieve more strict administrative management as well as the law maintenance.

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Geant4-DICOM Interface-based Monte Carlo Simulation to Assess Dose Distributions inside the Human Body during X-Ray Irradiation

  • Kim, Sang-Tae
    • International Journal of Contents
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    • 제8권2호
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    • pp.52-59
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    • 2012
  • This study uses digital imaging and communications in medicine (DICOM) files acquired after CT scan to obtain the absorbed dose distribution inside the body by using the patient's actual anatomical data; uses geometry and tracking (Geant)4 as a way to obtain the accurate absorbed dose distribution inside the body. This method is easier to establish the radioprotection plan through estimating the absorbed dose distribution inside the body compared to the evaluation of absorbed dose using thermo-luminescence dosimeter (TLD) with inferior reliability and accuracy because many variables act on result values with respect to the evaluation of the patient's absorbed dose distribution in diagnostic imaging and the evaluation of absorbed dose using phantom; can contribute to improving reliability accuracy and reproducibility; it makes significance in that it can implement the actual patient's absorbed dose distribution, not just mere estimation using mathematical phantom or humanoid phantom. When comparing the absorbed dose in polymethly methacrylate (PMMA) phantom measured in metal oxide semiconductor field effect transistor (MOSFET) dosimeter for verification of Geant4 and the result of Geant4 simulation, there was $0.46{\pm}4.69%$ ($15{\times}15cm^2$), and $-0.75{\pm}5.19%$ ($20{\times}20cm^2$) difference according to the depth. This study, through the simulation by means of Geant4, suggests a new way to calculate the actual dose of radiation exposure of patients through DICOM interface.

Experimental and numerical verification of hydraulic displacement amplification damping system

  • Chung, Tracy Sau-Kwai;Lam, Eddie Siu-Shu;Wu, Bo;Xu, You-Lin
    • Structural Engineering and Mechanics
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    • 제33권1호
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    • pp.1-14
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    • 2009
  • Hong Kong is now recognized as an area of moderate seismic hazard, but most of the buildings have been designed with no seismic provision. It is of great significance to develop effective and practical measures to retrofit existing buildings against moderate seismic attacks. Researches show that beam-column joints are critical structural elements to be retrofitted for seismic resistance for reinforced concrete frame structures. This paper explores the possibility of using a Hydraulic Displacement Amplification Damping System (HDADS), which can be easily installed at the exterior of beam-column joints, to prevent structural damage against moderate seismic attacks. A series of shaking table tests were carried out with a 1/3 prototype steel frame have been carried out to assess the performance of the HDADS. A Numerical model representing the HDADS is developed. It is also used in numerical simulation of the shaking table tests. The numerical model of the HDADS and the numerical simulation of the shaking table tests are verified by experimental results.

조모-어머니 관계질이 조모-손자녀 유대감에 미치는 영향: 공동양육의 매개효과를 중심으로 (Effect of Grandmother-Mother Relationship on Grandmother-Grandchildren Ties: Focusing on the Mediating Effect of Coparenting)

  • 최혜정;안정신
    • Human Ecology Research
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    • 제58권2호
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    • pp.149-161
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    • 2020
  • This study showed that the association between grandmother-mother relationship and grandmother-grandchildren ties is mediated by the coparenting. Participants consisted of 329 grandmothers who were rearing preschool aged grandchildren in the Seoul and Gyeonggido area. SPSS 23.0 performed descriptive statistical analysis and correlation analysis. The structural equation model was estimated with AMOS 23.0. Parameters were estimated using the maximum likelihood method. Model fit index used the chi-square statistic, the goodness of fit index (GFI), the Turker-Lewis index (TLI), the comparative fit index (CFI), the root mean square error of approximation (RMSEA). The mediation effect analysis followed a two-step verification process; direct and indirect effect. In addition, statistical significance of the indirect effect was examined using a bootstrapping procedure. The results are as follows. First, a positive correlation was found between the grandmother-mother relationship, grandmother-grandchildren ties, and coparenting. Second, the association between grandmother-mother relationship and grandmother-grandchildren ties is mediated by coparenting. The results of this study suggest that the quality of the grandmother's relationship with mothers and cooperative coparenting is important to building relationships with grandchildren. In addition, coparenting can be an important mechanism for grandmother-mother relationships and grandmother-grandchild ties. Based on the results of this study, we discussed ways to improve the grandmothers' relationship quality with the mother and strengthen parenting ability.

미쉐린 레스토랑 선택속성 중요도와 만족도에 관한 연구 - 스타 레스토랑과 빕 구르망 레스토랑을 중심으로 - (A Study on Importance and Satisfaction of Michelin Restaurant Selection Attributes - Starred Restaurants and Bib Gourmand Restaurants -)

  • 도현욱
    • 한국식생활문화학회지
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    • 제35권1호
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    • pp.55-64
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    • 2020
  • This study on the importance and satisfaction of selection attributes for customers using Michelin restaurants. The survey was conducted on 309 respondents who had visited and used restaurants by classifying the Michelin restaurants into starred restaurants and Bib Gourmand restaurants. The data was collected and the frequency analysis, t-test verification, and IPA analysis were performed using the SPSS 25.0 statistical program. The results of the study examined the difference between the importance and satisfaction of the choice of starred restaurants. Overall, the importance was higher than satisfaction. The importance of hygiene and cleanliness was recognized by many customers that the expectation for the overall Starred restaurants was very high. Bib Gourmand, showed that the importance was higher than satisfaction. In terms of importance and satisfaction, the taste of food is the most important and the satisfaction is high. Comparing the IPA analysis of the attributes of 1) hygiene and cleanliness, food quality, convenience, and facade of food, 2) service professionalism and variety of menus, 3) food price, atmosphere and amount, and 4) the attitude and kindness of the employees were shown. This study has great significance in providing practical basic data for the management of domestic Michelin restaurants.

과수재배지 비점오염부하량 추정회귀식 비교 검증 (Verification of Nonpoint Sources Runoff Estimation Model Equations for the Orchard Area)

  • 권헌각;이재운;이윤정;천세억
    • 한국물환경학회지
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    • 제30권1호
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    • pp.8-15
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    • 2014
  • In this study, regression equation was analyzed to estimate non-point source (NPS) pollutant loads in orchard area. Many factors affecting the runoff of NPS pollutant as precipitation, storm duration time, antecedent dry weather period, total runoff density, average storm intensity and average runoff intensity were used as independent variables, NPS pollutant was used as a dependent variable to estimate multiple regression equation. Based on the real measurement data from 2008 to 2012, we performed correlation analysis among the environmental variables related to the rainfall NPS pollutant runoff. Significance test was confirmed that T-P ($R^2=0.89$) and BOD ($R^2=0.79$) showed the highest similarity with the estimated regression equations according to the NPS pollutant followed by SS and T-N with good similarity ($R^2$ >0.5). In the case of regression equation to estimate the NPS pollutant loads, regression equations of multiplied independent variables by exponential function and the logarithmic function model represented optimum with the experimented value.

Factors Affecting Customer Brand Preference toward Electric Vehicle in Bangkok, Thailand

  • VONGURAI, Rawin
    • The Journal of Asian Finance, Economics and Business
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    • 제7권8호
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    • pp.383-393
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    • 2020
  • The purpose of this research is to identify factors affecting consumer's brand preference toward environment-friendly products like electric vehicles in Bangkok, Thailand. The researcher conducted the study based on a quantitative approach and adapted a nonprobability sampling as a convenience sampling method. The data were collected from 400 respondents living in Bangkok, who are 18 years old and above, with significant knowledge of electric vehicles. This study adapted the Structural Equation Model (SEM) and Confirmatory Factor Analysis (CFA) to examine the model accuracy, reliability and verification influence of various variables. The results revealed that social influence has significant effect on environment concern as well as a positive effect on attitude. The initial significance of environment concern leads to a positive effect on fuel efficiency, followed by brand preference. Lastly, attitude has a significant effect on brand preference as attitude of consumers toward environment-friendly products affects the encouragement of brand preference, which largely depends on individual opinion. From an environmental concern, the researchers identified fuel efficiency and attitude having a positive and significant effect on brand preference toward environment-friendly products for electric vehicles. The authors also found that environmental concern and social influences on green purchasing behavior were significantly interrelated.

레스토랑 고객의 선택 속성에 관한 실증적 연구 (A Study on the Choice Properties of Restaurant Customer's Characteristics)

  • 이광옥;최희중
    • 한국조리학회지
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    • 제13권4호
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    • pp.1-18
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    • 2007
  • The purpose of this study is to investigate the properties of restaurant customer's choice and to present the desirable service of restaurants. The experimental data were collected from the questionnaire answered by 182 restaurant customers in Seoul. One-way ANOVA and $x^2$(Chi-square) verification analysis were performed with the SPSS WINDOW 10.0 program to investigate statistical significance of the data. As the results, it was revealed that the food factor was most important when the customers choose a restaurant. And then, the importance of the choice properties was in the following order, that is, the food factor, the hygiene and cleanness factor, the employee's service factor, the visiting convenience factor, the indoor mood factor, the menu factor, the amenity factor for children. In addition, it was confirmed that some choice properties of the customers are dependent on the general characteristics such as sex, age, occupation, income etc. Therefore, it is essential that restaurants should provide various services related with the choice properties by understanding the choice properties according to the customer's characteristics.

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