• Title/Summary/Keyword: Second-order Factor Analysis

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Reliability Estimation of Static Design Methods for Driven Steel Pipe Piles in Korea (국내 항타강관말뚝 설계법의 신뢰성평가)

  • Huh, Jung-Won;Park, Jae-Hyun;Kim, Kyung-Jun;Lee, Ju-Hyung;Kwak, Ki-Seok
    • Journal of the Korean Geotechnical Society
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    • v.23 no.12
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    • pp.61-73
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    • 2007
  • As a part of Load and Resistance Factor Design(LRFD) code development in Korea, in this paper an intensive reliability analysis was performed to evaluate reliability levels of the two static bearing capacity methods for driven steel pipe piles adopted in Korean Standards for Structure Foundations by the representative reliability methods of First Order Reliability Method(FORM) and Monte Carlo Simulation(MCS). The resistance bias factors for the two static design methods were evaluated by comparing the representative measured bearing capacities with the design values. In determination of the representative bearing capacities of driven steel pipe piles, the 58 data sets of static load tests and soil property tests were collected and analyzed. The static bearing capacity formula and the Meyerhof method using N values were applied to the calculation of the expected design bearing capacity of the piles. The two representative reliability methods(FORM, MCS) based computer programs were developed to facilitate the reliability analysis in this study. Mean Value First Order Second Moment(MVFOSM) approach that provides a simple closed-form solution and two advanced methods of FORM and MCS were used to conduct the intensive reliability analysis using the resistance bias factor statistics obtained, and the results were then compared. In addition, a parametric study was conducted to identify the sensibility and the influence of the random variables on the reliability analysis under consideration.

A Study of the Possibility of Building Energy Saving through the Building Data : A Case Study of Macro to Micro Building Energy Analysis (건물데이터를 통한 건물에너지 절감 가능성에 대한 연구 : 도시단위의 거시적 분석부터 미시적 건물에너지 분석사례)

  • Cho, Soo Youn;Leigh, Seung-Bok
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.11
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    • pp.580-591
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    • 2017
  • In accordance with 2015 Paris agreement, each individual country around the world should voluntarily propose not only its (individual) reduction target, but also actively develop and present expansion targets of its scope and concrete reduction goals exceeding the previous ones. Accordingly, it is necessary to prepare a macroscopic, long-range strategy for reducing energy consumption and greenhouse gas emissions, which can cover a single building, town, city and eventually even a province. The purpose of this research is to gather and compile government-acquired data from various sources and (in accordance with contents and specificity), combine building data by stages by using multi-variable matrix and then analyze the significance of combined data for each stage. The first order data presents the probability and the cost effectiveness of energy saving on the scale of a city or a province, based only upon general information, size and power consumption of buildings. The second order data can identify a pattern of energy consumption for a building of a specific purpose and which tends to consume a larger amount of energy during one particular season (than others). Finally, the third order data can derive influential factors (base load, humidity) from the energy consumption pattern of a building, and thus propose an informed and practical energy-saving method to be applied in real time.

A Study on the Relationship between Public Service Announcement on Child Abuse and the Perception of Reporting by People Obliged to Report Child Abuse (아동학대 공익광고와 아동학대 신고의무자의 신고인식의 관계 연구)

  • Seo, Bokhyun
    • Journal of The Korean Society of Integrative Medicine
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    • v.6 no.3
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    • pp.43-57
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    • 2018
  • Purpose : The act of reporting child abuse by people obliged to report child abuse is a way to detect long-term incidents of child abuse in early stages and to prevent a vicious cycle of social crimes. Thus, this study intends to enhance the reporting of child abuse through a study on the perception of people obliged to report child abuse through the public service announcement on child abuse. Methods : First, in order to identify the demographic characteristics of the subjects, the frequency and percentage were calculated. Second, in order to verify the reliability of the variables, Cronbach ${\alpha}$ was calculated. Third, in order to examine the perception of people obliged to report child abuse and the perception of reporting, a t-test (verification) and One-way ANOVA were conducted. Fourth, in order to identify the relationship between variables, a Correlation analysis was conducted. Result : The results show that people obliged to report child abuse did not perceive the public service announcement on child abuse positively and it varied depending on their jobs. The correlation between the public service announcement on child abuse and sub-factor of perceptions of reporting showed that a positive correlation was found in reliability, interest, understanding, perceiving the public service announcement on child abuse, perceiving severity and effectiveness, whereas a negative correlation was found in perceiving hazards. Conclusion : The education for preventing child abuse is required by the job type of people obliged to report. It is necessary to convey the message of effective public service announcement. The public service announcements on child abuse must be nationwide and long-term projects.

Relation between Belief and Actual Practice of Instructor according to Education in Taekwondo Personality (태권도 지도자의 인성교육에 대한 신념과 지도실제와의 관계)

  • Lee, Jueng-Joo;Kim, Dong-Hyun
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.396-407
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    • 2012
  • The Purpose of this study was to examined the relation between Belief and Actual Practice of Instructor according to education in Taekwondo Personality. To get the purpose participants was selected 286 Taekwondo instructors. Selected data were analyzed for descriptive statistic, pearson relation analysis, and multi dimensional analysis with SPSS/PC 18.0. The result was as followed. First, there were different on frequency of important factors between belief and practice of Taekwondo personality based on Taekwondo instructor's cognitive. The order of ethological important factors on Taekwondo instructor's cognitive were manner, confidence, love, perseverance, bravery. But The order of ethological important factors on Taekwondo instructor's practice were manner, confidence, perseverance, leadership, honestly. Second, belief of Taekwondo personality based on Taekwondo instructor's cognitive has positive relationship with practice of Taekwondo personality in a part. There were positive relationship among factors of belief of Taekwondo personality but were lower positive relationship among factors of practice of Taekwondo personality. Taekwondo instructors' determination on teaching belief has positive effect on guidance factor, practical factor, variety factor, if the teaching belief has higher score then the teaching practice has higher practical teaching.

Needs Analysis on Secondary School Principals for Building Trust in Teachers (중등학교 교장의 교사신뢰 형성을 위한 요구도 분석)

  • Kwon, DaNam;Park, HwaChoon;Kim, DaeHyun;Lee, SangSoo;Byeon, YongCheol
    • Journal of the Korean Data Analysis Society
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    • v.20 no.6
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    • pp.3155-3167
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    • 2018
  • The purpose of this study was to investigate factor of principals' trust in teachers which principals of secondary school recognized and to explore their needs on building trust in teachers. For this purpose, this study used survey question of which investigated conception of principals' trust in teachers and performed with 296 secondary school principals. First, gap of two statuses was proven by t-test. Second, the order of priority was presented by Borich model. Third, the result of the locus for focus model was presented in the form of coordinate plane. Lastly, top priority and the second priority were determined. The result of this study was as following. 'Class management, instruction, and caring for students' category is highest in needs of secondary school principals on trust in teachers. Next, second priority category is 'partnership with parents'. It means secondary school principals recognize that students and parents are most important on education and their trust in teachers. Based on the review, finding and implications are discussed.

The Effect of Class Satisfaction among Students in the Department of Security Services on Career Decision Efficacy (경호학과 학생들의 전공수업만족도가 진로 결정 효능감에 미치는 영향)

  • Paek, Kyung-Hwa;Ji, Chi-Hwan
    • Korean Security Journal
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    • no.21
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    • pp.19-33
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    • 2009
  • This study attempted to investigate the effect of class satisfaction of the students majoring in the studies of security services on the efficacy of career decision. To do this, I chose 430 security services of the students majoring by the systematic stratified cluster random sampling as the subject of study. All data were analyzed the causal relationship of the collected equation. In order to do a data analysis used descriptive statistics analysis, t-test, one-way ANOVA and multiple regression analysis of SPSS. As a result, the following conclusion was drawn: First, it was found that there was not a statistically significant(learning factor, interpersonal relation, aptitude factor) difference in their major class satisfaction and career decision efficacy(goal choice, future plan, working information) according to gender. Second, it was found that there was a statistically signifiant difference in such factors as learning, interpersonal relations and aptitude, in relation to the difference in subfactor such as major class satisfaction and career decision efficacy. Third, it was found that the learning, aptitude and career factors of major class satisfaction had a statistically significant effect on the future plan. Fourth, it was found that he learning and career factors of major class satisfaction had a statistically significant effect on the resolution of the goal. Fifth, it was found that the aptitude and career factors of major class satisfaction had a statistically significant effect on job information. Sixth, it was found that the career factors of major class satisfaction had a statistically significant effect on the problem-solution. Therefore, we must first give priority to improve the class satisfaction. By doing this, we can raise the efficacy level of career decision.

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The Effect of Self-status Factors on Self-Efficiency and Job Satisfaction of Fire Service Officials (소방공무원의 자아상태 요인이 자아효능감과 직무만족도에 미치는 영향)

  • Kim, Yeob-Rae;Lee, Hae-Young
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.145-154
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    • 2019
  • The purpose of this study is to analyze the self-status of fire service personnel to identify their effect on self-efficacy and job satisfaction, and to improve the performance of their tasks in the field and perform their tasks efficiently. A survey of 177 current firefighters in the southern city of Gyeonggi Province conducted a correlation analysis and regression analysis through SPSS 22.0. The first study found that in relation to the self-status factor and the self-efficacy factor of firefighting services, the self-efficacy is rather high and the self-regulating effect is very high. Second, the effects of the self-status factor on the self-efficacy were significant in order of type Adult (A), type Free Child (FC), and type Adapted Child (AC). Third, analysis of correlation between self-status factors and job satisfaction factors showed inadequate correlation in all job satisfaction factors for Critical Parent (CP) types, and static correlation in all job satisfaction for Nurturing Parent (NP) types. Type Adapted Child (AC) was less satisfying to itself, to itself, to pay, to promote, to co-workers. Thus, the current strategic approach based on rationality needs to be strengthened by lowering the authority of the Critical Parent (CP) function in terms of self-status factors and enhancing the Adapted Child (AC) function in the lower satisfaction level of the parent.

Simplified procedure for seismic demands assessment of structures

  • Chikh, Benazouz;Mehani, Youcef;Leblouba, Moussa
    • Structural Engineering and Mechanics
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    • v.59 no.3
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    • pp.455-473
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    • 2016
  • Methods for the seismic demands evaluation of structures require iterative procedures. Many studies dealt with the development of different inelastic spectra with the aim to simplify the evaluation of inelastic deformations and performance of structures. Recently, the concept of inelastic spectra has been adopted in the global scheme of the Performance-Based Seismic Design (PBSD) through Capacity-Spectrum Method (CSM). For instance, the Modal Pushover Analysis (MPA) has been proved to provide accurate results for inelastic buildings to a similar degree of accuracy than the Response Spectrum Analysis (RSA) in estimating peak response for elastic buildings. In this paper, a simplified nonlinear procedure for evaluation of the seismic demand of structures is proposed with its applicability to multi-degree-of-freedom (MDOF) systems. The basic concept is to write the equation of motion of (MDOF) system into series of normal modes based on an inelastic modal decomposition in terms of ductility factor. The accuracy of the proposed procedure is verified against the Nonlinear Time History Analysis (NL-THA) results and Uncoupled Modal Response History Analysis (UMRHA) of a 9-story steel building subjected to El-Centro 1940 (N/S) as a first application. The comparison shows that the new theoretical approach is capable to provide accurate peak response with those obtained when using the NL-THA analysis. After that, a simplified nonlinear spectral analysis is proposed and illustrated by examples in order to describe inelastic response spectra and to relate it to the capacity curve (Pushover curve) by a new parameter of control, called normalized yield strength coefficient (${\eta}$). In the second application, the proposed procedure is verified against the NL-THA analysis results of two buildings for 80 selected real ground motions.

Determination of Resistance Factors of Load and Resistance Factor Design for Drilled Shaft Based on Load Test (LRFD 설계를 위한 현장타설말뚝의 주면지지력 저항계수 산정)

  • Kim, Seok-Jung;Kwon, Oh-Sung;Jung, Sung-Jun;Han, Jin-Tae;Kim, Myoung-Mo
    • Journal of the Korean Geotechnical Society
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    • v.26 no.7
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    • pp.17-24
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    • 2010
  • Load Resistance Factor Design method is used increasingly in geotechnical design world widely and resistance factors for drilled shafts are suggested by AASHTO. However, these resistance factors are determined for intact rock conditions; by comparison, most of bedrocks in Korea have weathered condition, so that applying the AASHTO resistance factors is not reasonable. Thus, this study suggests the proper resistance factors for design of drilled shaft in Korea. The 22 cases of pile load test data from 8 sites were chosen and reliability-based approach is used to analyze the data. Reliability analysis was performed by First Order Second Moment Method (FOSM) applying 4 bearing capacity equations. As a result, when the Factor of Safety (FOS) was selected as 3.0, the target reliability indexes (${\beta}_c$) were evaluated as 2.01~2.30. Resistance factors and load factors are determined from optimization based on above results. The resistance factors ranged between 0.48 and 0.56 and load factors for dead load and live load are evaluated as approximately 1.25 and 1.75 respectively. However, when the target reliabilities are considered as 3.0, the resistance factors are evaluated as approximately 50% of the results when the target reliability index was 2.0.

An Exploratory Study on the Components of Visual Merchandising of Internet Shopping Mall (인터넷쇼핑몰의 VMD 구성요인에 대한 탐색적 연구)

  • Kim, Kwang-Seok;Shin, Jong-Kuk;Koo, Dong-Mo
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.2
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    • pp.19-45
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    • 2008
  • This study is to empirically examine the primary dimensions of visual merchandising (VMD) of internet shopping mall, namely store design, merchandise, and merchandising cues, to be a attractive virtual store to the shoppers. The authors reviewed the literature related to the major components of VMD from the perspective of the AIDA model, which has been mainly applied to the offline store settings. The major purposes of the study are as follows; first, tries to derive the variables related with the components of visual merchandising through reviewing the existing literatures, establish the hypotheses, and test it empirically. Second, examines the relationships between the components of VMD and the attitude toward the VMD, however, putting more emphasis on finding out the component structure of the VMD. VMD needs to be examined with the perspective that an online shopping mall is a virtual self-service or clerkless store, which could reduce the number of employees, help the shoppers search, evaluate and purchase for themselves, and to be explored in terms of the in-store persuasion processes of customers. This study reviewed the literatures related to store design, merchandise, and merchandising cues which might be relevant to the store, product, and promotion respectively. VMD is a total communication tool, and AIDA model could explain the in-store consumer behavior of online shopping. Store design has to do with triggering a consumer attention to the online mall, merchandise with a product related interest, and merchandising cues with promotions such as recommendation and links that induce the desire to pruchase. These three steps might be seen as the processes for purchase actions. The theoretical rationale for the relationship between VMD and AIDA could be found in Tyagi(2005) that the three steps of consumer-oriented merchandising are a store, a product assortment, and placement, in Omar(1999) that three types of interior display are a architectural design display, commodity display, and point-of-sales(POS) display, and in Davies and Ward(2005) that the retail store interior image is related to an atmosphere, merchandise, and in-store promotion. Lee et al(2000) suggested as the web merchandising components a merchandising cues, a shopping metaphor which is an assistant tool for search, a store design, a layout(web design), and a product assortment. The store design which includes differentiation, simplicity and navigation is supposed to be related to the attention to the virtual store. Second, the merchandise dimensions comprising product assortments, visual information and product reputation have to do with the interest in the product offerings. Finally, the merchandising cues that refer to merchandiser(MD)'s recommendation of products and providing the hyperlinks to relevant goods for the shopper is concerned with attempt to induce the desire to purchase. The questionnaire survey was carried out to collect the data about the consumers who would shop at internet shopping malls frequently. To select the subject malls, the mall ranking data announced by a mall rating agency was used to differentiate the most popular and least popular five mall each. The subjects was instructed to answer the questions after navigating the designated mall for five minutes. The 300 questionnaire was distributed to the consumers, 166 samples were used in the final analysis. The empirical testing focused on identifying and confirming the dimensionality of VMD and its subdimensions using a structural equation modeling method. The confirmatory factor analysis for the endogeneous and exogeneous variables was carried out in four parts. The second-order factor analysis was done for a store design, a merchandise, and a merchandising cues, and first-order confirmatory factor analysis for the attitude toward the VMD. The model test results shows that the chi-square value of structural equation is 144.39(d.f 49), significant at 0.01 level which means the proposed model was rejected. But, judging from the ratio of chi-square value vs. degree of freedom, the ratio was 2.94 which smaller than an acceptable level of 3.0, RMR is 0.087 which is higher than a generally acceptable level of 0.08. GFI and AGFI is turned out to be 0.90 and 0.84 respectively. Both NFI and NNFI is 0.94, and CFI 0.95. The major test results are as follows; first, the second-order factor analysis and structural equational modeling reveals that the differentiation, simplicity and ease of identifying current status of the transaction are confirmed to be subdimensions of store design and to be a significant predictors of the dependent variable. This result implies that when designing an online shopping mall, it is necessary to differentiate visually from other malls to improve the effectiveness of the communications of store design. That is, the differentiated store design raise the contrast stimulus to sensory organs to promote the memory of the store and to have a favorable attitude toward the VMD of a store. The results that navigation which means the easiness of identifying current status of shopping affects the attitude to VMD could be interpreted that the navigating processes via the hyperlinks which is characteristics of an internet shopping is a complex and cognitive process and shoppers are likely to lack the sense of overall structure of the store. Consequently, shoppers are likely to be alost amid shopping not knowing where to go. The orientation tool enhance the accessibility of information to raise the perceptive power about the store environment.(Titus & Everett 1995) Second, the primary dimension of merchandise and its subdimensions was confirmed to be unidimensional respectively, have a construct validity, and nomological validity which the VMD dimensions supposed to have a positive correlation with the dependent variable. The subdimensions of product assortment, brand fame and information provision proved to have a positive effect on the attitude toward the VMD. It could be interpreted that the more plentiful the product and brand assortment of the mall is, the more likely the shoppers to favor it. Brand fame and information provision as well affect the VMD attitude, which means that the more famous the brand, the more likely the shoppers would trust and feel familiar with the mall, and the plentifully and visually presented information could have the shopper have a favorable attitude toward the store VMD. Third, it turned out to be that merchandising cue of product recommendation and hyperlinks affect the VMD attitude. This could be interpreted that recommended products could reduce the uncertainty related with the purchase decision, and the hyperlinks to relevant products would help the shopper save the cognitive effort exerted into the information search and gathering, which could lead to a favorable attitude to the VMD. This study tried to sheds some new light on the VMD of online store by reviewing the variables mentioned to be relevant with offline VMD in the existing literatures, and tried to link the VMD components from the perspective of AIDA model. The effect size of the VMD dimensions on the attitude was in the order of the merchandise, the store design and the merchandising cues.It is said that an internet has an unlimited place for display, however, the virtual store is not unlimited since the consumer has a limited amount of cognitive ability to process the external information and internal memory. Particularly, the shoppers are likely to face some difficulties in decision making on account of too many alternative and information overloads. Therefore, the internet shopping mall manager should take into consideration the cost of information search on the part of the consumer, to establish the optimal product placements and search routes. An efficient store composition would be possible by reducing the psychological burdens and cognitive efforts exerted to information search and alternatives evaluation. The store image is in most part determined by the product category and its brand it deals in. The results of this study support this proposition that the merchandise is most important to the VMD attitude than other components, the manager is required to take a strategic approach to VMD. The internet users are getting more accustomed and more knowledgeable about the internet media and more likely to accept the internet as a shopping channel as the period of time during which they use the internet to shop become longer. The web merchandiser should be aware that the product introduction using a moving pictures and a bulletin board become more important in order to present the interactive product information visually and communicate with customers more actively, therefore leading to making the quantity and quality of product information more rich.

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