• International Journal of Highway Engineering
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• v.9 no.4
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• pp.205-213
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• 2007

Strength relationships are presented through experimental data from the concrete strength tests in this study. Various strength tests such as the compressive, flexural, and splitting tensile strength and the modulus of elasticity are included. An experimental work was performed to determine the various strength characteristics for various mix designs. Three different coarse aggregates such as granite, limestone, sandstone were used and included were fine aggregates such as natural sand, washed sand and crushed sand. Also included was cement amount as experimental variable. It was confirmed that each strength value with respect to curing time is to follow a typical strength development curve. With this somewhat reliable test results various strength relationships such as flexural strength-compressive strength, splitting tensile strength-compressive strength, modulus of elasticity-compressive strength, splitting tensile strength-flexural strength were analyzed through statistics. Experimental data were well fitted to the 0.5-power relationship of flexural strength and compressive strength which has been commonly accepted. The splitting tensile strength is expected to be best in the linear relationship from the flexural strength data. Finally splitting tensile strength was found to be proportional to the 0.87 power of the cylindrical compressive strength.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4227-4239
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• 2013

Knowledge transfer occurs in various social contexts, within individuals and groups, and, thus, is closely linked to social networks in an organization. This paper applies social network theory and social identity theory to knowledge management area. The subject of this study was organization members who transfer their knowledge. 296 questionnaires were collected and analyzed. The results are as follows. First, in-group and out-group's tie strength have a significant effect on knowledge transfer. Second, the study shows that the knowledge transfer influences positively individual, team and organizational performance. Lastly, the study verifies that the applied knowledge has a moderating effect on the relationship of the in-group's tie strength and knowledge transfer.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.267-279
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• 2009

A numerical model that can simulate the nonlinear behavior of ultra high strength fiber reinforced concrete (UHSFRC) structures subjected to monotonic loading is introduced. The material properties of UHSFRC, such as compressive and tensile strength or elastic modulus, are different from normal strength reinforced concrete. The uniaxial compressive stress-strain relationship of UHSFRC is designed on the basis of experimental result, and the equivalent uniaxial stress-strain relationship is introduced for proper estimation of UHSFRC structures. The steel is uniformly distributed over the concrete matrix with particular orientation angle. In advance, this paper introduces a numerical model that can simulate the tension-stiffening behavior of tension part of the axial member on the basis of the bond-slip relationship. The reaction of steel fiber is considered for the numerical model after cracks of the concrete matrix with steel fibers are formed. Finally, the introduced numerical model is validated by comparison with test results for idealized UHSFRC beams.

• Explosives and Blasting
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• v.21 no.4
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• pp.23-35
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• 2003

This study is to clarify the comparative relationship and a mechanical anisotropy of rock on the subject of granite distributed in the Namwon area Uniaxial compressive and Brazilian strengths with respect to the horizontal and vertical axes of granite are shown the linear relation. In the case of the result of the p-wave velocity measurement. it is represented that the velocity of vortical direction is faster about 10 to 15% than other two horizontal directions. The difference between velocities is caused by a developmental pattern of microcracks distributed in rock. Moreover, this result is very consistent with the result investigated through thin sections. The proportion of uniaxial compression strength to Index of point load strength ($Is_{(50)}$) is 18~20 times in case of granite. Uniaxial compressive strength is relatively good relationship with point load strength, Schmidt hammer rebound value, and tensile strength point load strength of them is the best comparative relationship. It is indicated that point load test is the most useful tool to estimate uniaxial compressive strength, comparing with other experimental methods.

• Asia Marketing Journal
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• v.9 no.3
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• pp.33-73
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• 2007

This paper explores major factors that drive relationship quality and strength in business-to-business transactions. Three major factors, including offering characteristics, managers' interpersonal factors (similarity, expertise), and relational factors (relationship length, cooperation, and dependence), were proposed to affect relationship quality, and indirectly affect relationship strength. In addition, both economic/instrumental dimension (offering characteristics) and affective, relational dimensions (trust and commitment) are also expected to influence relationship strength. In the empirical study which used the textile-dyeing company managers' ratings of local exporters, structural equation modeling presented a well-fit evidence that relationship quality variables and strength are influenced by their proposed antecedents. Specifically, it was found that all characteristics (except relationship length) have direct effect on their relationship quality with local exporters, and indirectly impact on relationship strength which was measured along dimensions of intention to continue the business relationship in the future and the current share of business given to a local exporter. Together with the minor influence that instrumental dimension (offering characteristics) has on relationship strength, this study suggests that the willingness to remain in business relationship or current proportion of business shared is influenced more by affective assessment like relationship quality than by calculative motivation.

• Journal of the Korean GEO-environmental Society
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• v.7 no.2
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• pp.33-42
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• 2006

Eighteen biotite granites on Andong area and twenty seven igneous rocks(diorite, granite, andesite, rhyolite) on Yeosu area were tested to evaluate the correlations between the uniaxial compressive strength values, as determined by the standard uniaxial compression test, and the corresponding results of the ultrasonic velocity. The variability of test results for each test was evaluated by calculating the coefficient of determination or variation. Results indicate that strong correlations exist between the results of uniaxial compression vs the point load, Schmidt hammer and ultrasonic velocity test. The correlation equations for predicting compressive strength using different methods are presented along with their confidence limits. Ultrasonic velocity test used provide reliable estimates of compressive strength.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.9-15
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• 2011

The flexural behavior of the UHPFRC rectangular beam which has 100 MPa, 140 MPa compressive strength were compared with that of the typical RPC rectangular beam which has same geometrical shape, prestressd force and 160 MPa compressive strength. UHPFRC beam was not reinforced at all and the variable of test is fraction of steel fiber, compressive strength of concrete, method of prestressing and ratio of prestressing bar. The behavior of UHPFRC beam was analysed by relationship of moment - curvature and load - deflection. Simple modeling of stress-strain of UHPFRC was proposed. Based on the proposed constituted, the flexural moment-curvature relationship was calculated and compared with experimental data on prestressed UHPFRC beams. Good agreement between calculated strengths and experimental data is obtained.

• Journal of the Korea Concrete Institute
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• v.13 no.5
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• pp.447-456
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• 2001

Many investigators have tried to represent the nonlinear behavior of stress-strain relationship of concrete using mathematical curves. Most of empirical expressions for stress-strain relationship, however, have focused on old age concrete, and were not able to represent well the behavior of concrete at an early age. Where wide understanding on the behavior of concrete from early age to old age is very important in evaluating the durability and service life of concrete structures. In this paper, effect of 5 different strength levels and ages of from 12 hours to 28 days on compressive stress-strain relationship was observed experimentally and analytically. Tests were carried out on $\phi$100${\times}$200mm cylindrical specimens water-cured at 20${\pm}$3$^{\circ}C$. An analytical expression of stress-stain relationship with strength and age was developed using regression analyses on experimental results. For the verification of the proposed model, the model was compared with present and existing experimental data and some existing models. The analysis shows that the proposed model predicts well experimental data and describes well effect of strength and age on stress-strain relationship.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.169-175
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• 2011

Strength is one of the very important factors to evaluate the physical properties of concrete. Aggregate forms the most parts in concrete. Cement as a binder in concrete is also closely related to strength. This experiment was tested to understand the effect of the characteristics of aggregate and cement on the relationship between concrete compressive strength and Shear Wave velocity. It was experimented by the different types of cement and maximum coarse aggregate sizes. Type I cement and rapid setting cement was used. Aggregates from three different regions were used. Aggregate of 19mm and 13mm maximum coarse aggregate sizes was used for grading. The relationship between compressive strength and Shear Wave velocity was tested under the condition of same mixture. LA wear test was used to quantify the characteristics of aggregate. As a result, the relationship between concrete compressive strength and Shear Wave velocity was affected by the types of cement, but regular relationship was appeared regardless of types of aggregate, grading and abrasion ratio.

• 한국경영정보학회:학술대회논문집
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• 2007.11a
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• pp.361-366
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• 2007

정보시스템 아웃소싱(이후 아웃소싱으로 기술) 시장이 성장하고 있는 현실 속에서 기업에서는 아웃소싱을 통하여 많은 편익을 얻을 것으로 기대하고 있다. 이에 아웃소싱에 대한 기존 연구는 아웃소싱의 관리형태를 계약으로 대표되는 공식적인 관리와 신뢰로 대표되는 비공식적인 관리로 분류하고 이것이 아웃소싱 현장에서 어떤 성과를 가져오는가를 평가하였다. 하지만 아직까지 아웃소싱 결과에 만족하는 기업은 그리 많지 않은 실정이다. 본 연구는 기존 연구와 달리, 첫째, 통합적 관점에서 서비스 사용자의 아웃소싱 관리메커니즘 전개가 어떤 요인의 영향을 받는가를 알아보고, 둘째, 이렇게 전개된 아웃소싱 관리메커니즘의 정도가 아웃소싱 성과에 어떤 영향을 주는가를 검증해보고자 하였다. 특히 아웃소싱 관리메커니즘과 아웃소싱 성과의 관계에 있어 관계관리강도의 매개역할에 대하여 중점적으로 살펴보았다. 연구결과, 계약준비능력, 관계관리능력 등의 두 요인이 아웃소싱 관리메커니즘에 양(+)의 영향을 준다는 점을 실증적으로 검증하였다. 둘째, 아웃소싱 관리메커니즘과 아웃소싱 성과 둘 간의 관계를 관계관리강도가 매개하는 것을 확인하였다. 도출 결과를 중심으로 아웃소싱 관리에 대한 실무적인 시사점과 향후 연구방향을 논의하였다.