• Title/Summary/Keyword: Path-analysis

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Corrosion Characteristics of Excavated Bronze Artifacts According to Corrosion Environment (부식 환경에 따른 출토 청동 유물의 부식 특성)

  • Jang, Junhyuk;Bae, Gowoon;Chung, Kwangyong
    • Korean Journal of Heritage: History & Science
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    • v.53 no.1
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    • pp.24-33
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    • 2020
  • In excavated bronze artifacts, corrosion products of various shapes and colors are observed due to multiple corrosion factors coexisting in the burial environment, and these corrosion products can constitute important data not only in terms of long-term corrosion-related information, but also in connection with preservation of artifacts. As such, scientific analysis is being carried out on the corrosion layer and corrosion products of bronze artifacts, and the corrosion mechanism and the characteristics of corrosion products elucidated, which is essential for interpreting the exposed burial environment and its association with corrosion factors inside the burial environment. In this study, after classifying excavated bronze artifacts according to alloy ratio and fabrication technique, comprehensive analysis of the surface of corrosion artifacts, corrosion layer, and corrosion products was carried out to investigate the corrosion mechanism, formation process of the corrosion layer, and characteristics of corrosion products. The study designated two groups according to alloy ratio and fabrication technique. In Group 1, which involved a Cu-Sn-Pb alloy and had no heat treatment, the surface was rough and external corrosion layers were formed on a part, or both sides, of the inside and the outside, and the surface was observed as being green or blue. α+δ phase selection corrosion was found in the metal and some were found to be concentrated in an empty space with a purity of 95 percent or more after α+δ phase corrosion. The Cu-Sn alloy and heat-treated Group 2 formed a smooth surface with no external corrosion layer, and a dark yellow surface was observed. In addition, no external corrosion layer was observed, unlike Group 1, and α corrosion was found inside the metal. In conclusion, it can be seen that the bronze artifacts excavated from the same site differ in various aspects, including the formation of the corrosion layer, the shape and color of the corrosion products, and the metal ion migration path, depending on the alloy ratio and fabrication technique. They also exhibited different corrosion characteristics in the same material, which means that different forms of corrosion can occur depending on the exposure environment in the burial setting. Therefore, even bronze artifacts excavated from the same site will have different corrosion characteristics depending on alloy ratio, fabrication technique, and exposure environment. The study shows one aspect of corrosion characteristics in specific areas and objects; further study of corrosion mechanisms in accordance with burial conditions will be required through analysis of the corrosive layer and corrosive product characteristics of bronze artifacts from various regions.

Analysis of Semen Parameters, Sperm Activity, and Fertility of Somatic Cell Cloned Hanwoo Bulls (체세포 복제 한우 수소의 정액 성상, 정자의 활동성 및 수정 능력 분석)

  • Bae, Seong-Hoon;Hwang, Seong-Soo;Yang, Byong-Chul;Go, Yeoung-Kyu;Kim, Dong-Hoon;Im, Gi-Sun;Choi, Hwa-Sik;Jin, Dong-Il;Yang, Boh-Suk;Seong, Hwan-Hoo
    • Reproductive and Developmental Biology
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    • v.31 no.3
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    • pp.139-143
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    • 2007
  • This study was performed to investigate the reproductive characteristics of the cloned Hanwoo bulls produced by SCNT. The semen ejaculated from the cloned bulls (C-38 and C-39) and normal Hanwoo bull was properly measured the volume, the number of sperm, and the viability of frozen-thawed sperm. The sperm activity was analyzed using computer assisted sperm analysis (CASA). To analyze fertilizing ability of the cloned bulls, in vitro fertilization and artificial insemination were performed using the frozen-thawed semen. There were no differences in semen volume, sperm concentration, and the viability of frozen-thawed sperm between cloned bulls and normal bull. The difference was statistically significant in total motility, curvilinear velocity (VCL), straight-line velocity (VSL), and average-path velocity (VAP) of both cloned bulls compared to those of normal Hanwoo bull, respectively (p<0.05). The cleavage and blastocyst development rate were not different between the groups. five cloned cows were artificially inseminated using the frozen-thawed semen of C-38, two of them became pregnant. Two second generation calves (one male and one female) were produced. Based on these results, the cloned Hanwoo bulls showed normal reproductive abilities of semen parameters and sperm activity to their comparators and produced cloned calves, although there are some individual differences on the parameters.

A Structural Model for Quality of Life in Women Having Hysterectomies (여성의 자궁절제술후 삶의 질 구조모형)

  • 김숙남
    • Journal of Korean Academy of Nursing
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    • v.29 no.1
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    • pp.161-173
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    • 1999
  • The purpose of this study was to develope and test the structural model for quality of life in women having hysterectomies. A hypothetical model was constructed on the basis of previous studies and a review of literature. The conceptual framework was built around eight constructs. Exogenous variables included in this model were marital intimacy, importance of uterus, professional support, positive coping behavior and pre-operative symptoms. Endogenous variables were spouse's support, sense of loss and quality of life. Empirical data for testing the hypothetical model was collected using a self-report questionnare from 203 women having hysterectomies at the outpatient clinics of four general hospitals and a mail survey in Pusan City. The Data was collected from December, 1997 to January, 1998. Reliability of the eight instruments was tested with Cronbach's alpha which ranged from 0.639-0.915. For the data analysis, SPSS 7.5 WIN Program and LISREL 8.12 WIN Program were used for descriptive statistics and covariance structural analysis. The results of covariance structure analysis were as follows : 1. Hypothetical model showed a good fit with the empirical data. [$\chi$$^2$=6.93(df=5, P=.23), GFI=.99, AGFI=.94, RMSR=.019, NNFI=.97, NFI=.98, CN=440, standardized residuals(-2.14-2.10)] 2. For the parsimony of model, a modified model was constructed by deleting 3 paths and adding 1 path according to the criteria of statistical significance and meaning. 3. The modified model also showed a good fit with the data. [$\chi$$^2$=5.26(df=7, P=.63), GFI=.99, AGFI=.97, RMSR=.014, NNFI=1.02, NFI=.99, CN=710, standardized residuals(-1.46-1.70)] Results of the testing of the hypothesis were as follows : 1. Marital intimacy(${\gamma}$11=.78, t=14.37) and professional support(${\gamma}$13=.12, t=2.12) had a significant direct effect on the spouse's support. 2. Pre-operative symptoms(${\gamma}$25=.32, t=3.12), importance of uterus(${\gamma}$22=.20, t=2.61) and spouse's support($\beta$2l=-.19, t=-2.43) had a significant direct effect on the sense of loss. 3. Sense of loss($\beta$32=-.66, t=-9.83) had a direct effect on the quality of life. Marital intimacy had a direct(${\gamma}$31=.19, t=3.33), indirect(${\gamma}$31=.14, t=2.52) and total effect(${\gamma}$31=.25, t=4.41) on the quality of life. Professional support had a direct effect(${\gamma}$33=.11, t=2.07) and total effect(${\gamma}$33=.13, t=2.31) on the quality of life. The direct effect of pre-operative symptoms(${\gamma}$35=-.36, t=4.02) and positive coping behavior(${\gamma}$34=.15, t=2.06) had the insignificant effect on the quality of life while, due to the idirect effect these variables had overall significant effect on the quality of life. The results of this study showed that the sense of loss had the most significant direct effect on the quality of life. Marital intimacy, pre -operative symptoms and spouse's support had a significant direct effect on this sense of loss. These four variables, the sense of loss, marital intimacy, pre-operative symptoms and spouse's support, were identified as relatively important variables. The results of this study suggested that there is needed to determine if nursing intervention would alleviate this sense of loss and promote a greater quality of life in women who have had hysterectomies.

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A Study about the Effect of Team Members' Entrepreneurial Intention, Diversity, and Supporting Activities of Assistants on Team Learning Effectiveness and Educational Satisfaction in the Entrepreneurial Education of University Students through Team Learning (팀 학습을 통한 대학생의 창업교육에 있어서 팀원의 창업의지, 다양성 및 조력자의 지원활동이 팀 학습 유효성 및 창업교육 만족도에 미치는 영향에 관한 연구)

  • Choi, Joong Seog
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.4
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    • pp.159-174
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    • 2017
  • The purpose of this study was to examine whether the entrepreneurship education through team learning positively influences the effectiveness of team learning and the satisfaction of entrepreneurship curriculum. To do this, we analyzed the questionnaire data of 149 students who took the entrepreneurship course that was conducted by the team learning method focused on problem solving task among the entrepreneurship courses opened in the venture autonomous major. First, we examined the effect of team learning effectiveness and entrepreneurial education satisfaction on the effectiveness of the team learning by individual's intention for startup, diversity of team members, and supporting activities of assistants as independent variables. For this, hierarchical regression analysis was conducted to examine whether independent variables influenced the effectiveness of team learning, and whether the effectiveness of team learning mediates between these independent variables and entrepreneurial education satisfaction. The results of this study support the hypothesis that supporting activities of assistants will influence team learning effectiveness. However, the hypothesis that individual's intention for startup or team diversity influences team learning effectiveness was rejected. On the other hand, the results of the regression analysis show that individual's intention for startup has a significant effect on the satisfaction of entrepreneurship education. In addition, the effectiveness of team learning was found to be influential on the educational satisfaction, and it was verified that the effectiveness of team learning was mediating between the supporting activities of assistants and the satisfaction of entrepreneurship education. Especially, as a result of the hierarchical regression analysis, it was found that the significance of the supporting activities of assistants decreased remarkably. This suggests that the mediating path that affects the satisfaction of entrepreneurship education is very meaningful through the effectiveness of the team learning although the supporting activities of assistants are partially mediated. As a result of this study, it was found that the supporting activities of assistants are important in the team learning entrepreneurship education and it is also confirmed that the individual's intention for startup is also important. Especially, supporting activities of assistants were found to be an important factor affecting the satisfaction of entrepreneurship education through the effectiveness of team learning. Therefore, I think that it is essential to designing a practical education course that meets individual's intention for startup in the entrepreneurship education of university students and networking with the participation of internal and external experts or entrepreneurs. In addition, I think that it is necessary to think more thoughtfulness about the composition of team members in the team learning, and to provide more meticulous support to the effectiveness of the team learning.

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FACTORS AFFECTING CHILDREN'S DENTAL UTILIZATION: AN APPLICATION OF THE ANDERSEN MODEL (앤더슨 뉴만모형을 이용한 아동의 치과의료이용행태에 영향을 미치는 요인에 관한 연구)

  • Kim, Soo-Nam;Lee, Heung-Soo;Kim, Kyung-Hey;Kim, Dae-Eop;Park, Deug-Hee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.1
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    • pp.162-170
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    • 1998
  • The purpose of this study is to provide framework for understanding children's dental utilization. In this paper Andersen-Newman's model is applied to the use of dental visits. This model consists of predisposing, enabling, and need components that describe a person's decision to use dental health services. One thousand, nine hundred seven children and their mothers were selected for the study. The children were fourth grade to sixth grade in elementary schools in Iksan city, Korea. Models are operationalized using stepwise multiple regression analysis and path analysis. The number of independent variables used in the analysis was 39 in total, ie 32 predisposing components, 6 enabling components, and 1 need component. Children's Dental utilization was measured based on the number of visits. The data collected by means of a questionnaire survey. In this study, the amount of variance by the model was 25 percent. Predisposing factors had the greatest effect on utilization. Number of restricted activity days caused by oral disease, having a regular dental care, and susceptibility on oral disease of children were found to have significant major effects on dental utilization of children. Mother's dental visits was most important factor affecting dental utilization of children.

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Development of Analytic Hierarchy Process or Solving Dependence Relation between Multicriteria (다기준 평가항목간 중복도를 반영한 AHP 기법 개발)

  • 송기한;홍상연;정성봉;전경수
    • Journal of Korean Society of Transportation
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    • v.20 no.7
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    • pp.15-22
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    • 2002
  • Transportation project appraisal should be precise in order to increase the social welfare and efficiency, and it has been evaluated by only a single criterion analysis such as benefit/cost analysis. However, this method cannot assess some qualitative items, and cannot get a proper solution for the clash of interests among various groups. Therefore, the multi-criteria analysis, which can control these problems, is needed, and then Saaty has developed one of these methods, AHP(Analytic Hierarchy Process) method. In AHP, the project is evaluated through weighted score of the criteria and the alternatives, which is surveyed by a questionnaire of specialists. It is based on some strict suppositions such as reciprocal comparison, homogeneity, expectation, independence relationship between multi-criteria, but supposing that each criterion has independence relation with others is too difficult in two reasons. First, in real situation, there cannot be perfect independence relationship between standards. Second, individuals, even though they are specialists of that area, do not feel the degree of independence relation as same as others. This paper develops a modified AHP method for solving this dependence relationship between multi-criteria. First of all. in this method, the degree of dependence relationship between multi-criteria that the specialist feels is surveyed and included to the weighted score of multi-criteria This study supposes three methods to implement this idea. The first model products the degree of dependence relationship in the first step for calculating the weighted score, and the others adjust the result of weighted score from the basic AHP method to the dependence relationship. One of the second methods distributes the cross weighted score to each standard by constant ratio, and the other splits them using Fuzzy measure such as Bel and Pl. Finally, in order to validate these methods, this paper applies them to evaluate the alternatives which can control public resentments against Korean rail path in a city area.

A Comparative Analysis of Childcare Expansion and Social Investment in Sweden, France, Germany, the UK, Japan and South Korea (스웨덴, 프랑스, 독일, 영국, 일본, 한국의 아동 돌봄 체제와 사회투자에 대한 비교 연구)

  • An, Mi-Young
    • 한국사회정책
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    • v.20 no.2
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    • pp.169-193
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    • 2013
  • This paper examines how a social investment approach can be applied in a comparative analysis of childcare arrangements. We compared changes in Sweden, France, Germany, the UK, Japan and Korea during the 2000s, focusing on four dimensions of social investment: activation, gender equality, quality of care, and the degree of state's intervention in the family. We considered leave systems and the number of children enrolled in formal care and education facilities as indicators for labour market activation. For gender equality, women's position in employment is considered with respect to labour market participation rates, proportion of permanent employment, and wage-sex ratio. Quality of care concerns child-to-staff ratio and care provided with government quality control. The state's intervention was measured as social spending on families as proportions of GDP and total social spending. Our analysis provides empirical evidence that Sweden and France are pioneers in this arena and that the UK, Germany, Korea, and Japan are path-shifters in their care paradigms, albeit to varying degrees. Is the social investment approach an adequate paradigm for care? In a normative sense, this approach has potential. However, the following issues remain unaddressed: gender equality should be achieved through an expansion in good-quality jobs, fathers should be encouraged to take on childcare duties, and families should have universal access to good-quality childcare services controlled by the government.

Revision of Nutrition Quotient for Elderly in assessment of dietary quality and behavior (식사의 질과 식행동 평가를 위한 노인영양지수 개정 연구)

  • Lim, Young-Suk;Lee, Jung-Sug;Hwang, Ji-Yun;Kim, Ki-Nam;Hwang, Hyo-Jeong;Kwon, Sehyug;Kim, Hye-Young
    • Journal of Nutrition and Health
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    • v.55 no.1
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    • pp.155-173
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    • 2022
  • Purpose: This study was undertaken to update the Nutrition Quotient for Elderly (NQ-E), which reflects dietary quality and behavior among Korean older adults. Methods: The first 29 items of the measurable food behavior checklist were obtained from a previous NQ-E checklist, recent literature reviews, and national nutrition policies and recommendations. One-hundred subjects (50 men and 50 women) aged ≥ 65 years living in the Seoul Metropolitan Area, including Gyeonggi Province, completed a pilot survey from March to April 2021. Based on the results of the pilot study, we conducted factor analysis and frequency analysis to determine whether the items of the survey were properly organized and whether the distribution of answers for each evaluation item was properly distributed. As a result, we reduced the number of items on the food behavior checklist and used 23 items for the national survey. Nationwide, 1,000 subjects (472 men and 528 women) aged > 65 years, completed the checklist survey, which was applied using a face-to-face survey method from May to August 2021. The construct validity of the NQ-E 2021 was assessed using confirmatory factor analysis, LISREL. Results: Seventeen food behavior checklist items were selected for the final NQ-E 2021. Checklist items addressed three factors: balance (8 items), moderation (2 items), and practice (7 items). Standardized path coefficients were used as the weights of items to determine nutrition quotients. NQ-E and three-factor scores were calculated according to the weights of questionnaire items. Conclusion: The updated NQ-E 2021 produced by structural equation modelling provides a suitable tool for assessing the dietary quality and behavior of Korean older adults.

Revision of Nutrition Quotient for Korean adults: NQ-2021 (한국 성인을 위한 영양지수 개정: NQ-2021)

  • Yook, Sung-Min;Lim, Young-Suk;Lee, Jung-Sug;Kim, Ki-Nam;Hwang, Hyo-Jeong;Kwon, Sehyug;Hwang, Ji-Yun;Kim, Hye-Young
    • Journal of Nutrition and Health
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    • v.55 no.2
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    • pp.278-295
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    • 2022
  • Purpose: This study was undertaken to revise and update the Nutrition Quotient (NQ) for Korean adults, a tool used to evaluate dietary quality and behavior. Methods: The first 31 items of the measurable food behavior checklist were adopted based on considerations of the previous NQ checklist, recent literature reviews, national nutrition policies, and recommendations. A pilot survey was conducted on 100 adults aged 19 to 64 residing in Seoul and Gyeonggi Province from March to April 2021 using a provisional 26- item checklist. Pilot survey data were analyzed using factor analysis and frequency analysis to determine whether checklist items were well organized and responses to questions were well distributed, respectively. As a result, the number of items on the food behavior checklist was reduced to 23 for the nationwide survey, which was administered to 1,000 adults (470 men and 530 women) aged 19 to 64 from May to August 2021. The construct validity of the developed NQ (NQ-2021) was assessed using confirmatory factor analysis, linear structural relations. Results: Eighteen items in 3 categories, that is, balance (8 items), moderation (6 items), and practice (4 items), were finally included in NQ-2021 food behavior checklist. 'Balance' items addressed the intake frequencies of essential foods, 'moderation' items the frequencies of unhealthy food intakes or behaviors, and 'practice' items addressed eating behaviors. Items and categories were weighted using standardized path coefficients to calculate NQ-2021 scores. Conclusion: The updated NQ-2021 appears to be suitable for easily and quickly assessing the diet qualities and behaviors of Korean adults.

Revision of Nutrition Quotient for Korean adolescents 2021 (NQ-A 2021) (청소년 영양지수 (NQ-A 2021) 개정에 관한 연구)

  • Ki Nam Kim;Hyo-Jeong Hwang;Young-Suk Lim;Ji-Yun Hwang;Sehyug Kwon;Jung-Sug Lee;Hye-Young Kim
    • Journal of Nutrition and Health
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    • v.56 no.3
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    • pp.247-263
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    • 2023
  • Purpose: This study was conducted to update the Nutrition Quotient for Adolescents (NQ-A), which is used to assess the overall dietary quality and food behavior among Korean adolescents. Methods: The first 30 candidate items of the measurable eating behavior checklist were obtained based on a previous NQ-A checklist, the results of the seventh Korea National Health and Nutrition Examination Survey data, Korea Youth Risk Behavior Survey data, national nutrition policies and dietary guidelines, and literature reviews. A total of 100 middle and high school students residing in Seoul and Gyeonggi Province participated in a pilot study using the 25-item checklist. Factor analysis and frequency analysis were conducted to determine if the checklist items were organized properly and whether the responses to each item were distributed adequately, respectively. As a result, 22 checklist items were selected for the nationwide survey, which was applied to 1,000 adolescent subjects with stratified sampling from 6 metropolitan cities. The construct validity of the updated NQ-A 2021 was assessed using confirmatory factor analysis. Results: Twenty checklist items were determined for the final NQ-A 2021. The items were composed of three factors: balance (8 items), moderation (9 items), and practice (3 items). The standardized path coefficients were used as the weights of items to determine the nutrition quotients. NQ-A 2021 and 3-factor scores were calculated according to the weights of questionnaire items. The weight for each of the 3 factors was determined as follows: balance, 0.15; moderation, 0.30; and practice, 0.55. Conclusion: The updated NQ-A 2021 is a useful instrument for easily and quickly evaluating the dietary qualities and eating behaviors of Korean adolescents.