• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.3
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• pp.359-364
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• 2010

The objective of this study is to propose an effective method for measurement and analysis of fatigue crack. A technique that can measure the statue of fatigue crack propagation fast and correctly for enhancing safety of constructions and securing reliability is necessary. Moreover, the crack propagation behavior characteristics evaluation technique has to be developed using this technique. In this paper, fatigue crack was caused via the fatigue experiment with repeated load on the CT specimen that is made up of STS304. Fatigue crack propagation was measured by tracing the position of the maximum temperature according to the cycles using infrared thermography. The crack growth characteristics was evaluated by applying the moment values on the measuring area to the measured value. As a result of this study, the possibility that the infrared thermography could be applied to measure the fatigue crack was identified. Moreover, it was identified that fatigue crack propagation have a relationship with the moment value of construction.

• Smart Structures and Systems
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• v.12 no.2
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• pp.209-233
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• 2013

With an annual growth rate of about 30%, wind energy systems, such as wind turbines, represent one of the fastest growing renewable energy technologies. Continuous structural health monitoring of wind turbines can help improving structural reliability and facilitating optimal decisions with respect to maintenance and operation at minimum associated life-cycle costs. This paper presents an integrated monitoring system that is designed to support structural assessment and life-cycle management of wind turbines. The monitoring system systematically integrates a wide variety of hardware and software modules, including sensors and computer systems for automated data acquisition, data analysis and data archival, a multiagent-based system for self-diagnosis of sensor malfunctions, a model updating and damage detection framework for structural assessment, and a management module for monitoring the structural condition and the operational efficiency of the wind turbine. The monitoring system has been installed on a 500 kW wind turbine located in Germany. Since its initial deployment in 2009, the system automatically collects and processes structural, environmental, and operational wind turbine data. The results demonstrate the potential of the proposed approach not only to ensure continuous safety of the structures, but also to enable cost-efficient maintenance and operation of wind turbines.

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.1-6
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• 2008

The safety management of the LNG industry which shows huge growth recently, become an essential element. So the necessity of development for the pre-existing LNG storage/transport facility has been shown up and the improvement of information technology (IT) of these days make it possible to synthesize several models for integrated LNG facilitiy safety management system. This system will contains risk analysis/assessment technology, explosion, leakage and diffusion model construction technology, real-time monitoring and fault diagnosis technology, and reliability progression technology of process information through data reconciliation. The final integrated safety management system will contribute the increase of LNG industry's safety and exportation of technique.

• Industrial Engineering and Management Systems
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• v.13 no.2
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• pp.172-184
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• 2014

Economic growth with rising household income has put more vehicles on the roads worsening traffic congestion, road accidents, and air and noise pollution. This situation is further aggravated by the potential working population who choose to drive to work instead of taking public transportation. Public bus transport (PBT) plays an important role in alleviating these problems. PBT is underutilized in Malaysia, and there is an opportunity to increase ridership without substantial investment. Therefore, this study was conducted to investigate the factors that influence the use of PBT in Malaysia. The data were collected using structured questionnaires from 400 respondents. The results of the analysis show that the twin factors consisting of perceived satisfaction of and perceived importance by users towards safety and comfort of facilities and services offered by PBT are significantly related to intention to use those services. The satisfaction of availability of season tickets, the importance of reliability of bus schedule and time table, and the importance of ticket pricing are also significant. By providing insights for both public bus operators and the government, this paper contributes to mitigate the underutilization of PBT in Malaysia and the consequences of putting more vehicles on the roads. From the theory perspective, this paper also contributes by extending the theory of reasoned-action to transportation studies.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.863-872
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• 2021

The main goal of this research is to understand how small and medium enterprises (SMEs) owners in Oman perceive the factors that drive or impede their growth and sustainability. Based on survey data of 395 SMEs in Oman, factor analysis was conducted to check if all the items load as one factor in each of the constructs. The results show that all the items measuring motivators and barriers loaded significantly for the respective scales, with high reliability (Cronbach alpha for Motivators = 0.991 and Barriers = 0.995). Relationships between the demographic factors of entrepreneurs and firm characteristics were tested and it was found that all the four variables: age of the entrepreneur (p = 0.00), qualification of the entrepreneur (p = 0.00), SME sector (p = 0.00), and age of the firm (p = 0.00) have a significant relationship with both the Motivators and the Barriers. The findings of this study could have significant implications for policymakers in Oman and other Middle Eastern countries. Since SMEs face similar problems and are given priority around the world, the findings could be applicable to other countries, as well. The findings also add important results to the empirical literature on SMEs.

• Journal of Korean Dental Science
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• v.15 no.2
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• pp.101-111
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• 2022

The purpose of laboratory tests in the field of oral medicine can be divided into two categories: (1) medical evaluation of patients with systemic diseases that are planning to receive dental care and (2) diagnosis of patients with certain oral diseases. First, laboratory tests are commonly used to evaluate patients with systemic diseases who need dental management. A combination of multiple tests is usually prescribed as a test panel to diagnose and assess a specific disease. Test panels closely related to oral medicine include those for rheumatoid arthritis, connective tissue disease/lupus, liver function, thyroid screening, anemia, and bleeding disorders. Second, laboratory tests are used as auxiliary diagnostic methods for certain oral diseases. They often provide crucial diagnostic information for infectious diseases caused by bacteria, fungi, and viruses that are associated with pathology in the oral and maxillofacial regions. Laboratory tests for infectious diseases are composed of growth-dependent methods, immunologic assays, and molecular biology. As the field develops, further application of laboratory tests, including synovial fluid analysis in temporomandibular joint disorders, salivary diagnostics, and hematologic biomarkers associated with temporomandibular disorders and orofacial pain conditions, is currently under scrutiny for their reliability as diagnostic tools.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.73-81
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• 2023

Globalized cities are currently showing changes due to autonomous driving (AD). It is also maximizing globalization connections in cities where autonomous mobility is as complex as AD. The purpose of this study is to reveal that cities that realize AD and mobility will grow into globalized cities. Several cities, including New York and Shanghai, have attempted and are in progress, but failed cities are increasing. Although the technology of AD and the trust of citizens are prioritized, the city that has built the city's infrastructure is expected to be a city that has succeeded in AD. This is because commercialized cities or AVs will become hubs for mobility globalization, excluding rapid climate change or AV companies, and empirical analysis has been conducted that if AVs fail in metropolitan New York due to urban complexity (population density), urban economy size (GRDP), patents, number of consumers, infrastructure public EV chargers, and road quality. It examines whether the realization of AD by region and country affects overall national innovation. As a result, even if AV succeeds in large cities such as New York, Seoul, which has a higher population density (complexity), has a negative meaning, and a more similar Tokyo has a positive meaning. It can be seen that regional research on AV should also be prioritized in large cities such as Shanghai. This means that in order for AV to be realized in each city, the construction of AI infrastructure data must be actively changed to establish globalization of cities for economic growth as autonomous mobility.

• Asia pacific journal of information systems
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• v.34 no.1
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• pp.1-25
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• 2024

Consumer demand for e-commerce services has skyrocketed due to the introduction of social distancing standards and lockdown measures that countries have taken to combat the pandemic. There has been a notable surge in the popularity of on-demand delivery services, with a significant influx of new users turning to the e-platform for assistance. This research paper tries to identify the enablers of E-commerce Utility and Service Quality and establish a connection using total interpretive structural modelling (TISM). Enablers are the building blocks for providing customers with an enhanced and more consistent service experience contributing to service quality. The enablers and the linkages thus established hold valuable insights for e-commerce marketers, aiding them in effectively reaching their customers, and achieving desired growth outcomes. The TISM- based model and the MICMAC analysis identified two barriers; website design and personalization as the decisive attributes of e-commerce service quality, possessing strong driving power and weak dependence. Furthermore, the factors of reliability, responsiveness, information, and ease of use form the linkage zone, indicating that any action taken on these factors would not only influence other factors but also have a reciprocal effect on them.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.1
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• pp.103-111
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• 2017

In this study, the thermomechanical stress and fatigue analysis of a high voltage and high current (3,300 V/1200 A) insulated gate bipolar transistor (IGBT) module used for electric locomotive applications were performed under thermal cycling condition. Especially, the reliability of the copper wire and the ribbon wire were compared with that of the conventional aluminum wire. The copper wire showed three times higher stress than the aluminum wire. The ribbon type wire showed a higher stress than the circular type wire, and the copper ribbon wire showed the highest stress. The fatigue analysis results of the chip solder connecting the chip and the direct bond copper (DBC) indicated that the crack of the solder mainly occurred at the outer edge of the solder. In case of the circular wire, cracking of the solder occurred at 35,000 thermal cycles, and the crack area in the copper wire was larger than that of the aluminum wire. On the other hand, when the ribbon wire was used, the crack area was smaller than that of the circular wire. In case of the solder existing between DBC and base plate, the crack growth rate was similar regardless of the material and shape of the wire. However, cracking occurred earlier than chip solder, and more than half of the solder was failed at 40,000 cycles. Therefore, it is expected that the reliability of the solder between DBC and base plate would be worse than the chip solder.

• International Commerce and Information Review
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• v.16 no.1
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• pp.25-42
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• 2014

Since the reform and opening up in 1978, Chinese economy has been increasing rapidly with a high growth rate, but after 2012 the growth rate decreased as the reform of economic system. While economy in Africa began booming since 2000. Influenced by Global Financial Crisis and European Debt Crisis, economy in Africa slightly slowed down, but it was rebounding apparently from 2010. The urgent demand for energy and the sharp increasing in foreign exchange reserve pushes China to seek overseas markets. As Africa keeps a well relationship with China and the complementarity between China and Africa economy, Africa becomes one of the target markets for China's foreign development. Recently more and more enterprises begin to invest in Africa market. But till now the study on Africa mainly focuses on theoretical research based on real cases, and empirical research are very few and need to be increased. This thesis studies the influence of enterprise feature; local market feature and investment in foreign market on the result satisfaction of Chinese enterprises that invest in Africa markets. At the same time this thesis also studies and analyzes the market access strategy and marketing strategy for Chinese enterprises after entering overseas markets and put forward effective recommendation and suggestion for these enterprises. In order to proceed this study, 317 Chinese enterprises which invest in Africa have been investigated by me. And frequency analysis, reliability analysis, factor analysis, and simple regression analysis have also been conducted by SPSS18.0 APP to verify the hypothesis. The study result suggests that onlu investment in foreign market affects the Performance satisfaction of Chinese enterprises. And the market access strategy and marketing strategy play a role of the mediational effects when Chinese enterprises are investing in Africa.