• 한국국방경영분석학회지
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• 제10권1호
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• pp.23-39
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• 1984

Consider a failure model for a stochastic system. A shock is any perturbation to the system which causes a random amount of damage to the system. Any of the shocks can cause the system to fail at shock times. The amount of damage at each shock is a function of the sum of the magnitudes of damage caused from all previous shocks. The times between shocks form a sequence of independent and identically distributed random variables. The system must be replaced upon failure at some cost but it also can be replaced before failure at a lower cost. The long term expected cost per unit time criterion is used. Structural relationships of the optimal replacement policy under the appropriate regularity conditions will be developed. And these relationships will provide theoretical background for the algorithm development.

• 영어어문교육
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• 제7권2호
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• pp.55-75
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• 2002

The present study examined whether Kang's (1999) model of the relationships among language learning strategy use and language proficiency for the Asian students could be applied to a more heterogeneous group. In Kang's study, he collected information of language learning strategies of 957 foreign students learning English as a second language in American colleges through a questionnaire. He also measured the subjects' language proficiency with the Institutional Testing Program TOEFL (Test of English as a Foreign Language). This study analyzed the same data without the limitation of cultural identity. Structural equation modeling was used to model the relationships among strategy use and language proficiency. Then, the model of the present study was descriptively compared with Kang's (1999) model for the Asian students. The overall flow of the relationship paths appeared to vary very little across the two models, which would have indicated that the generalizability of Kang's (1999) model could be extended more than originally examined. (156)

• Archives of Pharmacal Research
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• 제29권7호
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• pp.582-586
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• 2006

Due to consumer reluctance to take synthetic drugs for nematode infections and the appearance of resistance to anthelminthic drugs, new drugs from natural products must be developed. Caenorhabditis elegans is one of the freely living nematodes and serves as a good model system for screening anthelminthic drugs. In this study, thirteen flavonoid derivatives were tested for anthelminthic activity and the relationships between their activities and structures were investigated. The structural information combined with the data for the larval growth inhibition of C. elegans provided meaningful structural insights in the search for new anthelminthic drugs.

• Structural Engineering and Mechanics
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• 제48권5호
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• pp.643-660
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• 2013

Reinforced concrete structures are vulnerable to high temperature conditions such as those during a fire. At elevated temperatures, the mechanical properties of concrete and reinforcing steel as well as the bond between steel rebar and concrete may significantly deteriorate. The changes in the bonding behavior may influence the flexibility or the moment capacity of the reinforced concrete structures. The bond strength degradation is required for structural design of fire safety and structural repair after fire. However, the investigation of bonding between rebar and concrete at elevated temperatures is quite difficult in practice. In this study, bond constitutive relationships are developed for normal and high-strength concrete (NSC and HSC) subjected to fire, with the intention of providing efficient modeling and to specify the fire-performance criteria for concrete structures exposed to fire. They are developed for the following purposes at high temperatures: normal and high compressive strength with different type of aggregates, bond strength with different types of embedment length and cooling regimes, bond strength versus to compressive strength with different types of embedment length, and bond stress-slip curve. The proposed relationships at elevated temperature are compared with experimental results.

• 가정과삶의질연구
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• 제30권3호
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• pp.69-82
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• 2012

The purpose of this study was to investigate the degree of sexual behavior. In particular, this study focused on the self-esteem, internet pornography addiction, and relationship satisfaction of freshmen as important predictors of sexual behavior and examined the dynamics of the relationships among the variables. The participants in this research were 1,806 university freshmen: 932 males and 828 females. All respondents submitted their answers on a self-report questionnaire. The data were analyzed with descriptive statistics and Pearson's correlations that used PASW 18.0, and AMOS 18.0, a statistical program for structural equation modeling(SEM), to estimate the hypothesized structural equation model. The major results of this study were as follows: (1) Relationship satisfactions mediated the relationships among self-esteem, internet pornography addiction, and sexual behavior. (2) Sexual behavior between male and female freshmen showed different influences on the test of the structural model invariance across the groups.

• 한국지역사회생활과학회지
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• 제26권3호
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• pp.523-540
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• 2015

This study examines the structural relationships between service quality, satisfaction, and behavioral intentions in responsible tourism. In particular, the study focuses on moderating effects of age. Data were collected from 471 tourists from seven responsible tourism agencies. SPSS 20.0 and AMOS 18.0 were used for frequency, reliability, exploratory factor, confirmatory factor, and path analyses. The results of a exploratory factor analysis yield two dimensions of service quality (functional quality and technical quality). The results of structural equation modeling indicate that functional quality and technical quality had positive effects on satisfaction, which in turn had a positive effect on behavioral intentions. In addition, age moderated the relationships between service quality, satisfaction, and behavioral intentions such that functional quality had a positive effect on satisfaction in the group of tourists in their twenties and thirties and that functional quality and technical quality were important factors for tourists in their forties. The results are expected to help responsible tourism communities better manage service quality to increase tourist satisfaction.

• Computers and Concrete
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• 제18권6호
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• pp.1175-1194
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• 2016

Nonlinear models, capable of taking into account all the phenomena involved in the cracking and in the failure of lightly reinforced concrete beams, are nowadays available for a rigorous calculation of the minimum reinforcement. To simplify the current approaches, a new procedure is proposed in this paper. Specifically, the ductility index, which is lower than zero for under-reinforced concrete beams in bending, is introduced. The results of a general model, as well as the data measured in several tests, reveal the existence of two linear relationships between ductility index, crack width, and the amount of steel reinforcement. The above relationships can be applied to a wide range of lightly reinforced concrete beams, regardless of the geometrical dimensions and of the mechanical properties of materials. Accordingly, if only a few tests are combined with this linear relationships, a new design-by-testing procedure can be used to calculate the minimum reinforcement, which guarantees both the control of cracking in service and the ductility at failure.

• 한국식생활문화학회지
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• 제22권5호
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• pp.582-589
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• 2007

The purpose of this study was to measure the causal relationships among affective belief, environmental belief, subjective norm, attitude and meat consumption behavior. A total of 318 questionnaires were completed. Structural equation model was used to measure the causal relationships among the constructs. Results of the study demonstrated that the structural analysis result for the data also indicated excellent model fit. The effects of affective belief, environmental belief and subjective norm on attitude were statistically significant. The effects of affective belief, environmental belief and subjective norm on meat consumption were statistically significant. As expected, attitude had a significant effects on behavioral intention. Moreover, attitude played a mediating role in the relationship between affective belief and meat consumption, environmental belief and meat consumption, subjective norm and meat consumption. Consumption played a mediating role in the relationship between attitude and behavioral intention. In conclusion, based on structural analysis, a model was proposed of interrelations among affective belief, environmental belief, subjective norm, attitude, meat consumption and intention. It should be noted that the original model was modified and should, preferably, be validated in future research. Other variables may be incorporated to form models that consist of new antecedent and consequence pairs.

• 한국조리학회지
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• 제23권1호
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• pp.48-57
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• 2017

With the increasing popularity of mobile commerce, restaurant service has become one of the leading service categories. Thus, this study attempted to understand the shopping behavior of restaurant mobile consumers by focusing on their shopping orientations. Specifically, this study investigated the structural relationships among shopping orientations, perceived value, concentration, and purchase intention in restaurant mobile commerce. Data analysis employing a structural equation approach was carried out for this study. Results revealed that, first, a consumer's shopping orientations was found to have a positive influence on perceived value, with time/convenience orientation possessing a stronger influence on perceived value than other factors (economic and hedonic). Second, a consumer's perceived value was found to affect concentration and purchase intention. Third, a consumer's concentration also appeared to influence purchase intention.

• International Journal of Concrete Structures and Materials
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• 제10권4호
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• pp.435-450
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• 2016

Experimental studies were conducted on 36 grouted splices to investigate their mechanical performance under four loading schemes: (1) incremental tensile loading, (2) repeated tensile loading, (3) cyclic loading at high stress, and (4) cyclic loading at large strain. Load-deformation responses of the grouted splices under cyclic loadings were featured with pinching effect and stiffness degradation compared to those responses under tensile loadings. The shape of the hysteresis loops of load-deformation curves was similar to that under incremental tensile loading. For the purpose of structural analysis, stress-strain relationships were presented for grouted splices under various loadings.