• Bulletin of the Korean Mathematical Society
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• v.47 no.5
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• pp.889-905
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• 2010

In this paper, a distribution free approach to the parameter estimation of a simple bilinear model with periodic coefficients is presented. The proposed method relies on minimum distance estimator based on the autocovariances of the squared process. Consistency and asymptotic normality of the estimator, as well as hypotheses testing, are derived. Numerical experiments on simulated data sets are presented to highlight the theoretical results.

• Journal of Advanced Marine Engineering and Technology
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• v.14 no.2
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• pp.48-65
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• 1990

Numerical solutions of the Navier-Stokes equations, governing 2-dimensional, time-dependent, viscous, incompressible fluid flow past a square cylinde in an infinite region, are presented for Reynolds numbers $10^2$, $10^3$and $10^4$. Finite-difference scheme, based on SOLA-VOF is adopted and a discretization of the convection term for irregular grid is newly suggested by altering the original nonconservation form into conservation one. Distribution of finer grids around the body reveals fairly reasonable consistency with the experimental variables : drag coefficient, lift coefficient, Strouhal number, fluctuating pressure coefficient, etc.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.213-214
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• 2006

The results of investigations in screw design for metall injection molding (MIM) will be presented. The consistency of cavity pressure, metering time and MFQ (monitoring of feedstock quality; parameter measured during metering) was chosen to compare different screws. A simulation program was used to optimize the conveying and melting mechanisms in the plastification unit. The theoretical background of this simulation programm will be explained.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.640-645
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• 2001

In order to evaluate the change in plasma and fecal mineral content of calves to 6 days of age, and to clarify the relationship between electrolyte status and fecal consistency in calves at 6 days of age, data were collected from 52 Holstein calves. Fecal DM and Na of calves decreased at 6 days of age, but fecal Ca, P, Mg, K, Fe and Zn increased. Plasma Ca, inorganic P, Mg, Na, and Fe as well as blood hematocrit and hemoglobin of calves decreased at 6 days of age, but plasma alkaline phosphatase increased. Colostral Ca, P, Mg, Fe and Zn decreased with time postpartum, but colostral Na and K were not affected. The high plasma Na and K of calves at 6 days of age were influenced by the values at birth. There were negative correlations between fecal DM and fecal Na, and fecal K, of calves at 6 days of age, negative correlations between fecal DM and plasma Na, with plasma K. Plasma and fecal Na as well as plasma and fecal K of calves at 6 days of age were increased by the occurrence of diarrhea. These results suggest that the electrolyte status of calves at 6 days of age is adversely affected by the occurrence of diarrhea, and high plasma K and Na of calves at 6 days of age may be partly due to the electolyte status of calves at birth.

• Journal of Venture Innovation
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• v.1 no.2
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• pp.1-12
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• 2018

The applications of psychology principles in marketing areas were pervasived. As the importance of digital marketing has increased, the cases of applications of psychology principles in digital marketing areas also has increased. This study analnyzed digital marketing cases based on the psychology principles of social proof, scarcity and loss aversion, reciprocity, commitment and consistency, anchoring. Cases were analnyzed amomg USA and Korea in digital marketing areas. This attempt will facilitating interdisciplinary research. It also will improve customer engagement, increase customer life value, and develope virtuous circle of customer journey through optimal user interface and message strategies.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.165-171
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• 2014

PURPOSES : The objective of this study is to find Percentile Speed($V_p$) for Appraisal of Road Section with Recurring Congestion. METHODS : Percentile Speed($V_p$) is determined by correlation analysis of CSI that proposed existing literature. and CSI(Consistency Service Index) is a index that subtract service fail frequency from 100 points, and service fail is defined as traffic situation is driving less than 80kph speed. In this study, We analyzed the highest correlation percentile speed associated with CSI. This speed is chosen as a delay decision speed. In order to verifying reliability, it performed a comparison with the previous method. RESULTS : As a result, 30 percentile speed($V_{30}$) was decided as index speed for judgement of recurring congestion section, and through comparison with existing methods, we demonstrated that 30 percentile speed can be useful for judgement of recurring congestion section. CONCLUSIONS : This method to Determine recurring congestion section using the percentile speed($V_{30}$) was proposed for the first time in this paper. This method can be applicated more quickly and easily than existing method for determining of recurring delay section.

• International Journal of Highway Engineering
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• v.17 no.6
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• pp.117-126
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• 2015

PURPOSES : This study prioritizes potential technology for establishing a safe work zone environment on roadways. We consider almost all conceivable technologies that enable mitigation of unexpected accidents for both road workers and drivers. METHODS : This study suggests a methodology to set the priority of potential technology for establishing a safe work zone environment by using the analytical hierarchy process (AHP). For this purpose, the AHP structure was first developed. Thereafter, a web-based survey was conducted to collect experts' opinions. Based on the survey results, weights associated with the relevant criteria of the developed structure were estimated. With the consistency index (CI) and consistency ratio (CR), we verified the estimated weights. In addition, a sensitivity analysis was performed to confirm whether the estimated weights were reliable. We finally proposed the priority for potential technology for establishing a safe work zone environment on roadways. RESULTS : In the first level, safety technology has the highest priority, and real-time information delivery for work zone, hazard warning for drivers, and temporal automated operation for traffic facilities were selected in the second level of hierarchy. CONCLUSIONS : The results imply that establishing the priority will be useful to establish a future road map for improving the work environment for road workers and drivers by employing appropriate protection facilities and developing safety systems.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.251-260
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• 2009

Objectives : To investigate reliability and validity of Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index. Methods : The reliablity, construct validity of the Korean WOMAC Index in the patient of knee osteoarthritis was investigated. Test-retest reliability was quantified with pearson's correlation coefficient and intraclass correlation coefficient. Internal consistency was quantified with Cronbach's ${\alpha}$. and construct validity with pearson's correlation coefficient by correlating of the Visual Analog Scale(VAS). Results : Test-retest reliability of Korean WOMAC Index for pain was 0.76 to 0.95, stiffness was 0.89 to 0.94, and physical function was 0.71 to 0.95. Intraclass correlation coefficient for pain was 0.76 to 0.94, stiffness was 0.54 to 0.89, and physical function was 0.70 to 0.95. Internal consistency were 0.94 and 0.94 for the first and second time, respectively. Construct validity for pain was 0.79, for stiffness was 0.66, and physical function was 0.67. Conclusions : The Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index is reliable, valid assessment tool in knee osteoarthritis.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.493-501
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• 2016

In-network storage is an effective technique for avoiding network congestion and reducing power consumption in continuous data collection in wireless sensor networks. In recent years, network coding based storage design has been proposed as a means to achieving ubiquitous access that permits any query to be satisfied by a few random (nearby) storage nodes. To maintain data consistency in continuous data collection applications, the readings of a sensor over time must be sent to the same set of storage nodes. In this paper, we present an efficient approach to updating data at storage nodes to maintain data consistency at the storage nodes without decoding out the old data and re-encoding with new data. We studied a transmission strategy that identifies a set of storage nodes for each source sensor that minimizes the transmission cost and achieves ubiquitous access by transmitting sparsely using the sparse matrix theory. We demonstrate that the problem of minimizing the cost of transmission with coding is NP-hard. We present an approximation algorithm based on regarding every storage node with memory size B as B tiny nodes that can store only one packet. We analyzed the approximation ratio of the proposed approximation solution, and compared the performance of the proposed coding approach with other coding schemes presented in the literature. The simulation results confirm that significant performance improvement can be achieved with the proposed transmission strategy.

• Journal of Intelligence and Information Systems
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• v.9 no.3
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• pp.49-63
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• 2003

This paper proposes and implements a tool for the development of efficient and reliable expert system. In the expert system the inference is executed, based on the knowledges stored in the knowledge base of specific domain. To acquire the reliable results of inference, the expert system requires the facilities which can access the various kinds of knowledge and maintain the consistency and accuracy of knowledge. In this context this paper implemented the knowledge management system which maintains the consistency and accuracy of knowledge, adding selectively the knowledges without error to the knowledge base by verifying their error before the knowledges are added to the knowledge base. At the same time this paper made the expert system call and use the procedural knowledge and the declarative knowledge in the data base so that it might use the various kinds of knowledge in the process of inference.