• The Journal of Korean Academy of Prosthodontics
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• v.27 no.2
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• pp.53-78
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• 1989

This study was taken to observe the changes of the residual stress in the alloy and to measure 3 dimensional distortions of the long span ceramo-metal bridge. The materials used in this study were Pors-on 4 (Pd-Ag alloy), and Ceramco and Vita VMK 68 powders. The residual stress of the alloy was measured on the six specimens (dia. 8m/m) by the X-ray diffraction stress analyzer according to the kind of ceramic powder and different measuring stages. And, for the measurement of the distortions, fifteen specimens of the anterior 8-unit ceramo-metal brige were fabricated and subjected to the 3-D coordinate measuring machine. Variables included the 2 kinds of a ceramic powder and the presence or absence of a splint bar at the cast metal framework. The measuring stages in both were after casting, after degassing and after glazing. The following conclusions were obtained : 1. The residual stress of the alloy showed increasing tendency for the tension by the ceramic fusing, but there was not significance. 2. The tendency of the distortions in the cast metal frameworks were decrease of the width, the anterior displacement and sagging. 3. The amount of the distortions at the degassing stage were greater than that at the ceramic fusing stage. 4. The splint bar was effective to control the distortion only at ceramic fusing stage. 5. The sagging distortion in the Ceramco firing were even through all measuring stages, but in the Vita firing, pronounced at degassing stage.

• Smart Structures and Systems
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• v.26 no.2
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• pp.227-239
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• 2020

Despite proven effectiveness and accuracy in laboratories, the existing damage assessment based on guided ultrasonic waves (GUWs) or acoustic emission (AE) confronts challenges when extended to real-world structural health monitoring (SHM) for railway tracks. Central to the concerns are the extremely complex signal appearance due to highly dispersive and multimodal wave features, restriction on transducer installations, and severe contaminations of ambient noise. It remains a critical yet unsolved problem along with recent attempts to implement SHM in bourgeoning high-speed railway (HSR). By leveraging authors' continued endeavours, an SHM framework, based on actively generated diffuse ultrasonic waves (DUWs) and a benchmark-free condition contrast algorithm, has been developed and deployed via an all-in-one SHM system. Miniaturized lead zirconate titanate (PZT) wafers are utilized to generate and acquire DUWs in long-range railway tracks. Fatigue cracks in the tracks show unique contact behaviours under different conditions of external loads and further disturb DUW propagation. By contrast DUW propagation traits, fatigue cracks in railway tracks can be characterised quantitatively and the holistic health status of the tracks can be evaluated in a real-time manner. Compared with GUW- or AE-based methods, the DUW-driven inspection philosophy exhibits immunity to ambient noise and measurement uncertainty, less dependence on baseline signals, use of significantly reduced number of transducers, and high robustness in atrocious engineering conditions. Conformance tests are performed on HSR tracks, in which the evolution of fatigue damage is monitored continuously and quantitatively, demonstrating effectiveness, adaptability, reliability and robustness of DUW-driven SHM towards HSR applications.

• Information Systems Review
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• v.8 no.2
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• pp.189-209
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• 2006

Business expects that IT investment would maximize the effects, like availability, timeliness, rapidity of information, by practical using of information technology for a strategic goal. However, it is not clear yet that IT investment would increase business productivity and could create profitability in the end-the linkage between IT investment and business KPI(Key Performance Indicator). In this case study(only provides post-evaluation case), we suggested integrated IT ROI(Return On Investment) methodology with a consistent and integrated view, on the base of practical implementation at Korean financial company. Especially, we evaluated connection between IT and business strategy, made business-related IT KPI development methodology, suggested framework for sustainable IT evaluation and management.

• Smart Structures and Systems
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• v.26 no.5
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• pp.657-666
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• 2020

A rotational pulse-echo ultrasonic propagation imager that can inspect cylindrical specimens for material nondestructive evaluations is proposed herein. In this system, a laser-generated ultrasonic bulk wave is used for inspection, which enables a clear visualization of subsurface defects with a precise reproduction of the damage shape and size. The ultrasonic waves are generated by a Q-switched laser that impinges on the outer surface of the specimen walls. The generated waves travel through the walls and their echo is detected by a Laser Doppler Vibrometer (LDV) at the same point. To obtain the optimal Signal-to-Noise Ratio (SNR) of the measured signal, the LDV requires the sensed surface to be at a right angle to the laser beam and at a predefined constant standoff distance from the laser head. For flat specimens, these constraints can be easily satisfied by performing a raster scan using a dual-axis linear stage. However, this arrangement cannot be used for cylindrical specimens owing to their curved nature. To inspect the cylindrical specimens, a circular scan technology is newly proposed for pulse-echo laser ultrasound. A rotational stage is coupled with a single-axis linear stage to inspect the desired area of the specimen. This system arrangement ensures that the standoff distance and beam incidence angle are maintained while the cylindrical specimen is being inspected. This enables the inspection of a curved specimen while maintaining the optimal SNR. The measurement result is displayed in parallel with the on-going inspection. The inspection data used in scanning are mapped from rotational coordinates to linear coordinates for visualization and post-processing of results. A graphical user interface software is implemented in C++ using a QT framework and controls all the individual blocks of the system and implements the necessary image processing, scan calculations, data acquisition, signal processing and result visualization.

• The Journal of Information Systems
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• v.27 no.2
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• pp.197-219
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• 2018

Purpose The purpose of this study is to examine what motivates users to adopt one of the emerging applications for collaborative consumption of sharing economy. Using the self-determination theory, motivation theory and TAM(Technology Acceptance Model) as the theoretical framework, this study illustrates important factors that influence adoption of collaborative consumption service. We develops the ICTs(Information and Communications Technologies) initiatives and motivation model to collaborative consumption. Design/methodology/approach This paper makes use of a quantitative methodology using survey questionnaire that allows for the measurement of the eight constructs(System Availability, Contents Quality, Design & Personalization, Security & Privacy, Emotional & Social Value, Economic Value, Attitude, Adoption & Consumption) contained in the hypothesized theoretical model on the basis of the prior literatures. Data collected from a sample of 227 respondents who have used the collaborative consumption services and provided the foundation for the examination of the proposed relationships in the model. Findings This study has the following implications for the users and providers of CC platforms and services. The ICTs initiatives (System Availability, Contents Quality, Design & Personalization, Security & Privacy) are the influential factors that motivate the emotional and social value to CC. On the other hand, The ICTs initiatives (System Availability, Contents Quality) are not very significant factors of economic value to CC. The empirical analysis result indicate that there are significant causal effect among emotional & social value, economic value, and adoption to CC. This study provides important theoretical implications for innovation adoption research through an empirical examination of the relationship between ICTs initiatives, motivation factors to collaborative consumption in the sharing economy.

• Journal of Korean Academy of Nursing
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• v.29 no.3
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• pp.639-655
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• 1999

An explanatory design was employed to identify the relationship of physical, emotional & social readjustment and social support of post hospitalized stroke patients and their caregivers. A convenient sample of 254 patients who given follow-up care at the outpatient department after discharge and 225 caregivers were recruited. Mental Status Questionnaire (MSQ), Social Support Inventory Stroke Survivors (SSISS), Illness intrusiveness(II), Instument Activity of Daily Living(IADL), Center of Epidemilogic Studies-Depression(CES-D), social activity and caregiver burden were used for measurement in this study. Results showed patient's physical level measured by IADL and psychological level measured by depression were high. But social activity was low. Cognitive function, depression & social activity were not significantly different by the posthospitalized period, but IADL was. The source of professional support was mostly the physician at the outpatient department. The family support was found significantly related to patient's depression & social activity and caregiver's subjective burden. Professional support was found significantly related to patient's IADL & depression. Illness intrusiveness as a mediating variable was a sig nificantly predicting power on patient's IADL & depression. The path analysis was used to identify the variables to predict the physical, emotional, and social status of patients. As a result, patient's age, cognitive function, illness intursiveness and professional support significantly predicted the level of IADL ; patient's cognitive function, illness intrusiveness and family support significantly predicted the level of depression ; and patient's age and family support significantly predicted the level of social activity of posthospitalized stroke patients. Based upon these results, the rehabilitation programs to reduce the illness intrusiveness and improve cognitive funtion were recommended for the readjustment of the stroke patients. This model of the readjustment of the posthospitalized stroke patients is recommended as the framework for care of the stroke patients.

• Journal of KIISE:Software and Applications
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• v.36 no.1
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• pp.1-9
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• 2009

In heterogeneous and distributed computing environments, with an increasing number of Web services providing similar functionalities, the reliability of Web services is a critical decision factor. To fulfill the open business model such as cooperation among enterprises, several Web services can be composed into the upper level business transaction. In Web services composition, the reliability of services is more and more critical. Though each unit Web service can be reliable, the reliability of the composed service is not guaranteed. Thus a way to efficiently assess and select composed Web services is needed. In this paper, we define new metrics for measuring the trust value of Web services, and propose an evaluation method to predict the trustworthy degree of the composed services based on the metrics. We also define a conceptual framework to support optimal Web services selection based on the proposed trust evaluation method. By selecting using the quantitative measurement rather than intuitive selection of the service user, it allows the service users to select the high reliable service meeting their quality requirements well.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.291-301
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• 2011

This research describes the comparison broker's role and its effectiveness measurement framework of comparison shopping. We verified seller-led comparison challenge method provide comparison information of products to buyers more efficiently. Buyer's satisfaction of purchase (S) can be defined as an interactive function between seller's competitiveness vector (P) of products that supplied to the market, and buyer's informed level vector (B) of products that is known from a lot of sources. Then the buyer's informed level can be changed through the information analysis among products by transformation process using comparison matrix (C). So the role of comparison shopping is to construct a comparison matrix and to serve it to the buyers, and to change the buyer's informed level. The changed informed level influences a buyer's satisfaction, that improved satisfaction of purchase is defined as the effectiveness of comparison shopping. As a perfect construction and usage of comparison matrix is impossible, a more efficient method for improving the comparison effectiveness is the comparison challenge. This research shows that comparison shopping makes 9.32% and comparison challenge makes 19.11% enhancement of comparison effectiveness through television market data experiments.

• Korea Journal of Hospital Management
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• v.18 no.4
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• pp.113-130
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• 2013

The aim of this article is to propose a framework for standardization of knowledge based on a case study of clinical operation to guide initial hospital knowledge management projects. Both quantitative and qualitative data for the project from 2009 through 2012 were collected for analysis. In a study of knowledge management project of a lab in S Hospital's Eye Center, this research examines the standardization of operational knowledge for competence enhancement of the lab. The lab defined and standardized the knowledge concern of the lab operation and the in-group from 2008. Organizations are often unaware of the potential value of tacit knowledge in both clinical and administrative area. The main finding from the case study is that analysis of such tacit knowledge of a lab in a hospital can be transformed into explicit knowledge for organizational capabilities such as improved quality, responsiveness and competitive advantage. Concepts from Nonaka's theory are used to investigate processes of knowledge standardization, examining the strategic value of tacit knowledge and the need to rely primarily on internal documentation processes. Since there has been limited research on hospital knowledge management. it may also be useful to researchers in generating propositions for further study.

• Journal of Korea Port Economic Association
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• v.28 no.1
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• pp.203-227
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• 2012

Based on the review of the existing studies, this study built the conceptual framework describing the structural relationships among port service quality dimensions(port internal service quality, external service quality, interaction quality), customer satisfaction, customer trust and customer loyalty. In specific, switching barrier was included as moderator in customer satisfaction and customer loyalty relationships. The subjects are the customers who use the Busan New Port. A survey using 317 customers was conducted, Confirmatory factor analysis was conducted to test the validity of the measurement model, and AMOS analysis approach was used to gain important insights into how customer retention in the port business can be ensured. Results in this paper indicate that customer trust and satisfaction are identified as antecedents of the port service quality dimensions. Customer satisfaction positively influences trust. Customer trust and satisfaction positively influence loyalty. Switching barrier positively moderates the relationship of customer satisfaction and customer loyalty. Finally, this study suggests that the implications of these findings and offers directions for future research.