• 한국식품조리과학회지
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• 제26권5호
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• pp.511-520
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• 2010

The purpose of this article was to study how the 7Ps influence consumers' risk perception of eating at family restaurants in Seoul. In this study, frequency analysis, reliability analysis, factor analysis and path analysis (SEM) of the data were performed. First, reliability analysis confirmed that the 7Ps performance and risk data could be used in this investigation. Path analysis showed that the 7Ps significantly influenced customers' risk perception of eating at restaurants in Seoul. According to the results, product negatively influenced performance risk (p<0.05) and financial risk (p<0.001); price negatively influenced performance risk (p<0.001), financial risk (p<0.001), and time risk (p<0.01); place negatively influenced performance risk (p<0.01) and time risk (p<0.001); promotion negatively influenced financial risk (p<0.05) and time risk (p<0.001); process negatively influenced performance risk (p<0.001) and time risk (p<0.001); physical evidence negatively influenced performance risk (p<0.05) and financial risk (p<0.001); and people negatively influenced performance risk (p<0.05), financial risk (p<0.001), and time risk (p<0.001). As a result, we confirmed that 7Ps were an effective marketing tactic for reducing consumers' risk perception of eating at restaurants. Therefore, family restaurant companies are recommended to administer the 7Ps without additional cost.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1636-1639
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• 2005

The process equipment and remote handling for the deep geological disposal of high-level radioactive waste(HLW) should be checked prior to the operation in view of reliability and operability. In this study, the concept of virtual environment workcell is implemented to analyze and define the feasible disposal process instead of real mock-up, which is very expensive and time consuming. To do this, the parts of process equipment for the disposal and maintenance will be modeled in 3-D graphics, assembled, and kinematics will be assigned. Also, the virtual workcell for the encapsulation and disposal process of spent fuel will be implemented in the graphical environment, which is the same as the real environment. This virtual workcell will have the several functions for verification such as analyses for the equipment's work space, the collision detection, the path planning and graphic simulation of the processes etc. This graphic virtual workcell of the HLW disposal process can be effectively used in designing of the processes for the hot cell equipment and enhance the reliability of the spent fuel management.

• Journal of Electrical Engineering and Technology
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• 제12권6호
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• pp.2278-2288
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• 2017

Multilevel converter topologies are widely used in many applications. The cascaded H-bridge multilevel inverter (CHBMI), which is one of many multilevel converter topologies, has been introduced as a useful topology in high and medium power. However, it has a drawback to require a lot of switches. Therefore, the reliability of CHBMI is important factor for analyzing the performance. This paper presents a simple switch fault diagnosis method for single-phase CHBMI. There are two types of switch faults: open-fault and short-fault. In the open-fault, the body diode of faulty switch provides a freewheeling current path. However, when the short-fault occurs, the distortion of output current is different from that of the open-fault because it has an unavailable freewheeling current flow path due to a disconnection of fuse. The fault diagnosis method is based on the zero current time analysis according to zero-voltage switching states. Using the proposed method, it is possible to detect the location of faulty switch accurately. The PSIM simulation and experimental results show the effectiveness of proposed switch fault diagnosis method.

• 디지털산업정보학회논문지
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• 제12권1호
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• pp.71-79
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• 2016

The main security threats in MANET are integrity and non-repudiation. In the meantime, a lot of secure routing protocols have been designed in order to block these security threats. In this paper, partnership-based authentication technique is proposed in order to provide participation exclusion of network and non-repudiation for the nodes. The proposed technique is a technique that participates in data communication for only the nodes receiving the authentication through the authentication process for the nodes. For this, the proposed technique is largely consists of two steps. The first step is the process that issued the certificate after the reliability for the nodes participating in the network is evaluated. And in the second step, the key exchange agreement with the neighbor nodes is performed and data communication is made after setting security path with responding nodes. The level of security in data transmission is improved because the process of path setting is performed through cooperation with a neighboring nodes having high reliability during the course of these two steps. The superiority of proposed technique in this paper was confirmed through the comparative experiment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권1호
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• pp.45-61
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• 2010

In the communication channel, the received signal is affected by many factors that can cause errors. These effects mean that received signal strength (RSS) based methods incur more errors in measuring distance and consequently result in low precision in the location detection process. As one of the approaches to overcome these problems, we propose using direction calibration to improve the performance of the RSS-based method for distance measurement, and sequentially a weighted least squares (WLS) method using reliability factors in conjunction with a conventional RSS weighting matrix is proposed to solve an over-determined localization process. The proposed scheme focuses on the features of the RSS method to improve the performance, and these effects are proved by the simulation results.

• 제어로봇시스템학회논문지
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• 제6권6호
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• pp.433-440
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• 2000

To flexibly evaluate performance and reliability of a real-time system which is intrinsically characterized by stringent timing constraints to generate correct responses, we propose fuzzyrandom variables and build a discrete event model embedded with fuzzy-random variables. Also, we adapt fuzzy-variables to a path-space approach, which derives the upper and lower bounds of reliability by using a semi-Markov model that explicitly contains the deadline information. Consequently, we propose certain formulas of state automata properly transformed by fuzzy-random variables, and present numerical examples applying the formulas to RTP(Rapid Thermal Process) to show that a complex system can be properly evaluated based on this model by computer simulation.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권7호
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• pp.363-369
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• 2000

To flexibly evaluate performance and reliability of an electric power system in the aspect of the real-time system which is intrinsically characterized by stringent timing constraints fails catastrophically if its control input is not updated by its digital controller computer within a certain time limit called the hard deadline, we propose fuzzy-random variables and build a discrete event model embedded with fuzzy-random variables. Also, we adapt fuzzy-variables to a path-space approach, which derives the upper and lower bounds of reliability by using a semi-Markov model that explicitly contains the deadline information. Consequently, we propose certain formulas of state automata properly transformed by fuzzy-random variables, and present numerical examples applying the formulas as well.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권4호
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• pp.499-507
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• 2018

Autonomous Underwater Vehicle (AUV), which are becoming more and more important in ocean exploitation tasks, needs energy conservation urgently when sailing the complex mission path in long time cruise. As hull lines optimization design becomes the key factor, which closely related with resistance, in AUV preliminary design stage, uncertainty parameters need to be considered seriously. In this research, Myring axial symmetry revolution body with parameterized expression is assumed as AUV hull lines, and its travelling resistance is obtained via modified DATCOM formula. The problems of AUV hull lines design for the minimum travelling resistance with uncertain parameters are studied. Based on reliability-based optimization design technology, Design For Six Sigma (DFSS) for high quality level is conducted, and is proved more reliability for the actual environment disturbance.

• 품질경영학회지
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• 제11권2호
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• pp.10-17
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• 1983

The former paper (Part I) studies two methods for searching and determining the simple paths in an acyclic or a cyclic network. The two methods are computer programmed as subroutines (SPLP1 and SPLP2) for various use. And a few examples of its applications are discussed Another paper (Par II) studies the reliability computation for a network by using the Event Space Methods. A computer program is developed for the computation by applying the SPLP2 subroutine subprogram. In this paper the former results are summarized with another computer program for reliability computation by using the Path Tracing Methods. The two subroutines appear in the Appendix as reference for others. The programs can be used in the reliability computation of reducible and irreducible structure networks.

• Geomechanics and Engineering
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• 제17권6호
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• pp.597-606
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• 2019

Ultrasonic Time-of-Flight Diffraction (TOFD) techniques are useful methods for non-destructive evaluation of fracture characteristics. This study focuses on the reliability and accuracy of ultrasonic diffraction methods to estimate the depth of rock fractures. The study material includes three different rock types; andesite, basalt and ignimbrite. Four different ultrasonic techniques were performed on these intact rocks. Artificial near-surface fracture depths were created in the laboratory by sawing. The reliability and accuracy of each technique was assessed by comparison of the repeated measurements at different path lengths along the rock surface. The standard error associated with the predictive equations is very small and their reliability and accuracy seem to be high enough to be utilized in estimating the depth of rock fractures. The performances of these techniques were re-evaluated after filling the artificial fractures with another material to simulate natural infills.