• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.4
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• pp.352-356
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• 2011

The isolation performance of a linear vibration isolator is limited to the ratio of stiffness to mass it supports. The stiffness of the isolator must be large enough to hold the weight. This results in the deterioration of the isolation performance. Recently, to overcome this fundamental limitation, the HSLDS(high-static-low-dynamic-stiffness) magnetic vibration isolator was introduced and its isolation characteristic was investigated theoretically. In this paper, the isolation performance of the HSLDS magnetic isolator is examined experimentally. Considerable amount of experiments are performed by carefully considering nonlinear characteristics. The experimental results verify the practical usability promisingly and agree with the theoretical studies, i.e. its performance is largely dependent on the key design parameter.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.5
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• pp.100-107
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• 2000

The hydraulic couplings have been widely used in industries, automobile, and power-station drives including ships. A mathematical analysis by which the design and application of hydraulic couplings are made is used in conventional design formulae and general roto-dynamic theories. The fluid flow of hydraulic couplings can be considered to have two component, one circumferentially about the coupling axis, and the other passing fluid from the pump to the turbine in the plane of the coupling axis. Tests have been carried out on the full-scale production coupling. The performance test consists of taking measurement of torque of the fluid coupling for three different amount of working fluid inside with various loads to the output shaft. The purpose of this research is to construct the experimental test equipments and to establish a series of performance test for the domestically developed hydraulic couplings, and to obtain experimental results which can be used to improve the performance of the hydraulic coupling and to solve the practical problems confronted in operation.

• Knowledge Management Research
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• v.16 no.1
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• pp.1-19
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• 2015

Although the interaction effects of knowledge sourcing strategies vary depending on environmental conditions such as knowledge intensity, most prior empirical research have failed to prove the effects of environmental conditions on the relationship between knowledge sourcing strategies and firm performance. In order to fill this gap, this study examines how knowledge intensity affects the relationship between knowledge sourcing strategies and firm performance. The results of this study indicate the interaction effects of knowledge sourcing strategies in high knowledge intensity environment are different from the effects in low knowledge intensity environment. This study expands knowledge management research by identifying the effects of knowledge intensity on the relationship between knowledge sourcing strategies and firm performance. Furthermore, it offers valuable practical guidelines for managers in selecting successful combinations of knowledge sourcing strategies with the consideration of knowledge intensity.

• Knowledge Management Research
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• v.20 no.4
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• pp.1-22
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• 2019

The purpose of this study is to investigate the role of IT-enabled dynamic capability in the relationship between intellectual capital and innovation performance under Industry 4.0. We approach the intellectual capital from the perspective of the resource-based view and define the components of intellectual capital as human capital, social capital, and organizational capital. On the other hand, the IT-based dynamic capability means that the information technology and the utilization ability of the enterprise are combined to overcome the turbulent environment. The empirical results showed that the IT-enabled dynamic capabilities mediated the relationship between intellectual capital and innovation performance as it revealed in theory. And in terms of practical implications, we found the importance of an organization's information technology ability to effectively utilize intangible resources for organizational performance.

• 유체기계공업학회:학술대회논문집
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• 1998.02a
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• pp.63-72
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• 1998

This study Is on the performance prediction and design of sirocco fan. Slip coefficient is very important factor for the performance analysis of centrifugal-type fan. Because generally used slip coefficient equations of backward curved centrifugal fan are not appropriate for forward curved sirocco fan, in this study a proper slip coefficient equation for sirocco fan is suggested. Using this equation performance prediction program for sirocco fan is composed and also included the total noise prediction that include turbulent noise at the fan Inlet and boundary layer noise. A comparison between the values obtained from performance prediction program and experimental values shows that the program predicts the sirocco fan performance in a practical rate.

• Proceeding of KASS Symposium
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• 2005.05a
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• pp.227-235
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• 2005

The earthquake-resistant structural systems have to ensure the sufficient stiffness and ductility for the stability. For those purposes, recently, the performance design concept to increase the degree of absorbed energy level of structures has been proposed. One practical way of the performance design in the spatial structures is to apply the isolation system to boundary parts of roof system and sub-structure to obtain the target performance. So, it is necessary to examine the characteristics of dynamic behavior of spatial structures governed by higher modes rather than lower modes different from the cases of high rise buildings. The objectives of this paper are to develop the equivalent model to simplify the analytical processes and to investigate the dynamic behavior of roof system according to the mass and the stiffness of sub-structures as a fundamental study of performance design for the spatial structures.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.159-168
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• 2013

Construction projects have become increasingly complex in recent years, resulting in substantial safety hazards and frequent fall accidents. In an attempt to prevent fall accidents, various safety management systems have been developed. These systems have mainly been evaluated qualitatively and subjectively by practitioners or supervisors, and there are few tools that can be used to quantitatively evaluate the performance of safety management systems. We propose an expertise-based safety performance evaluation model (EXSPEM), which integrates a fuzzy approach-based analytic hierarchy process and a regression approach. The proposed model uses S-shaped curves to represent the degree of contribution by subjective expertise and is verified by a genetic algorithm. To illustrate its practical application, EXSPEM was applied to evaluate the safety performance of a newly developed real-time mobile detector monitoring system. It is expected that this model will be a helpful tool for systematically evaluating the application of a robust safety control and management system in a complex construction environment.

• Culinary science and hospitality research
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• v.14 no.2
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• pp.46-60
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• 2008

In the hotel industry, there are the production and consumption of services at the same time, considering direct contact between employees and customers. In this respect, this study was conducted based on more practical factors to grasp employees' feelings and conflicts. The results of this research are as follows. First, individual conflicts among hotel banquet employees influence devotion to the organization which has a direct effect on performance of management. Second, such devotion is closely correlated with the factors of the performance of management. Finally, managing employees' conflicts is the key factor to promote the performance of management. Under these circumstances, there should be more concern in solving problems among employees and special pro-grams for promoting job satisfaction and devotion which bring about more profits as well as a sense of achievement.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7C
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• pp.594-597
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• 2010

This paper estimates belief-propagation (BP) decoding performance of moderate-length irregular low-density parity-check (LDPC) codes with sphere bounds. We note that for moderate-length($10^3{\leq}N{\leq}4\times10^3$) irregular LDPC codes, BP decoding performance, which is much worse than maximum likelihood (ML) decoding performance, is well matched with one of loose upper bounds, i.e., sphere bounds. We introduce the sphere bounding technique for particular codes, not average bounds. The sphere bounding estimation technique is validated by simulation results. It is also shown that sphere bounds and BP decoding performance of irregular LDPC codes are very close at bit-error-rates (BERs) $P_b$ of practical importance($10^{-5}{\leq}P_b{\leq}10^{-4}$).

• Journal of Information Technology Applications and Management
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• v.20 no.4
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• pp.293-313
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• 2013

Preproject phase is an important but often ignored research area in information systems field although it has an undeniable importance for successful project. The purpose of this study is to identify factors affecting project performance in preproject phase and to find empirically critical factors among them. After deriving 9 factors through literature review including clear project definition, project leader position, staffing efforts, preproject team expertise, preproject knowledge scope, preproject partnering, top-management support, resource sufficiency, and project climate, the study investigate the influence of those factors on project performance. The study results reveal that clear project definition, project climate, resource sufficiency, pre-project knowledge scope, project leader position have significant impact on project process satisfaction, a measure of project performance, but the other factors do not. Based on the empirical results, the study discuss academic and practical implications.