• Journal of Periodontal and Implant Science
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• v.48 no.2
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• pp.103-113
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• 2018

Purpose: The purpose of this retrospective study with 4-12 years of follow-up was to compare the marginal bone loss (MBL) between external-connection (EC) and internal-connection (IC) dental implants in posterior areas without periodontal or peri-implant disease on the adjacent teeth or implants. Additional factors influencing MBL were also evaluated. Methods: This retrospective study was performed using dental records and radiographic data obtained from patients who had undergone dental implant treatment in the posterior area from March 2006 to March 2007. All the implants that were included had follow-up periods of more than 4 years after loading and satisfied the implant success criteria, without any peri-implant or periodontal disease on the adjacent implants or teeth. They were divided into 2 groups: EC and IC. Subgroup comparisons were conducted according to splinting and the use of cement in the restorations. A statistical analysis was performed using the Mann-Whitney U test for comparisons between 2 groups and the Kruskal-Wallis test for comparisons among more than 2 groups. Results: A total of 355 implants in 170 patients (206 EC and 149 IC) fulfilled the inclusion criteria and were analyzed in this study. The mean MBL was 0.47 mm and 0.15 mm in the EC and IC implants, respectively, which was a statistically significant difference (P<0.001). Comparisons according to splinting (MBL of single implants: 0.34 mm, MBL of splinted implants: 0.31 mm, P=0.676) and cement use (MBL of cemented implants: 0.27 mm, MBL of non-cemented implants: 0.35 mm, P=0.178) showed no statistically significant differences in MBL, regardless of the implant connection type. Conclusions: IC implants showed a more favorable bone response regarding MBL in posterior areas without peri-implantitis or periodontal disease.

• Asia pacific journal of information systems
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• v.19 no.1
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• pp.147-165
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• 2009

Virtual community(VC) will increasingly be organized as commercial enterprises, with the objective of earning an attractive financial return by providing members with valuable resources and environment. For example, Cyworld.com in Korea uses several community services to enable customers of Cyworld to take control of their own value as potential purchasers of products and services. Although initial adoption is important for online network service success, it does not necessarily result in the desired managerial performance unless the initial usage is continuously related to the continuous usage and purchase. Particularly, the customer who receives relevant online services and is well equipped with online network services, will trust the online service provider and perceive less risk and experience more activities such as continuous usage and purchase. Thus, how to promote continued online service usage or, alternatively, how to prevent discontinuance is a critical issue for VC service providers to consider. By aggregating a wide range of information and online environments for customers and providing trust to its members, the service providers of virtual communities help to reduce the perceived risk of continuous usage and purchase. Drill down, online service managers realize that achieving strong and sustained customers who continuously use online service and purchase on it is crucial. Therefore, the research into this online service continuance will identify the relationship between the initial usage and the continuous usage and purchase. The research of continuous usage or post adoption has recently emerged as an important issue in the IS literature. Individuals' information systems(IS) continuous usage decisions are congruent with consumers' repeat purchase decisions. The TAM(Technology Acceptance Model) paradigm has been strongly confirmed across a wide range from product purchase on EC to online service usage contexts. The analysis of IS usage based on TAM has proven to be successful across almost online service contexts. However, most of previous studies have focused on only an area (i.e., VC or EC). Just little research has tried to analyze the relationship between VC and EC. The effect of some factors on user intention, captured through several theories such as TAM, has been demonstrated. Yet, few studies have explored the salient relationships of VC users' EC acceptance. To fill this gap between VC and EC research, this paper attempts to develop a research model that extends the TAM perspective in view of the additional contributions of trust in the service provider and trust in members on some factors that affect EC and VC adoption. In this extension, we applied the TAM-to-TAM(T2T) model, and analyzed the transfer effect of trust between these two TAMs. The research model was empirically tested on the context of a social network service. The model was to extend TAM with the trust concept for the virtual community environment from the perspective of tasks. By building an extended model of TAM and examining the relationships between trust and the existing variables of TAM, it is aimed to explain a user's continuous intention to use VC and purchase on EC. The unit of analysis in this paper is an individual user of a virtual community. The population of interest is the individual with the experiences in virtual community. The data for this paper was made available via a Web survey of VC users. In total, 281 cases were gathered for about one week, but there were some missing values in the sample and there were some inappropriate cases. Thus, only 248 cases were finally analyzed. We chose the structural equation analysis to test the hypotheses and it is better suited for explaining complex relationships than the other methods. In this test, AMOS was used to test the Structural Equation Model (SEM). Noticeable results have been found in the T2T model regarding the factors affecting the intention to use of virtual community and loyalty. Our result showed that trust transfer plays a key role in forming the two adoption beliefs. Overall, this study preliminarily confirms the salience of trust transfer in online service.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.253-260
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• 2013

We investigated the toxicological effects of Aroclor 1254 on the fertilized eggs, embryos and larvae of the olive flounder Paralichthys olivaceus. The survival rate and hatching success of the embryos decreased significantly in treated groups in an Aroclor 1254-dose-dependent manner. Significant differences were found at ${\geq}5{\mu}g/L$ Aroclor 1254 compared to the control group. Hatching success occurred at ${{\leq}}10{\mu}g/L$ Aroclor 1254, which was not significantly different to the control. Embryo malformation increased significantly at ${\geq}1{\mu}g/L$, and included yolk-sac and tail-flexure abnormalities. There was a significant decrease in the survival rate of the larvae at ${\geq}5{\mu}g/L$, which was accompanied by the malformations described above. Notably, concentrations as low as $1{\mu}g/L$ caused a significant increase in abnormalities in the larvae, including incidences of multi-focal hemorrhages, pericardial and yolk-sac edema, inhibition of swim bladder inflation and severe developmental delay. The responses to Aroclor 1254-induced toxicity were generally similar among fertilized eggs, embryos and larvae from three separate flounder hatcheries: Cheju Island, Yeosu and Chungnam, South Korea. These results indicate the high acute toxicity of Arolcor 1254 concentrations of which as low as $1{\mu}g/L$ in olive flounder larvae can affect unhatched embryos. To conclude, the average $LC_{50}$ values for Aroclor 1254 in the embryos and larvae were 50.92 and $3.08{\mu}g/L$, respectively. Additionally, the average $EC_{50}$ values, based on the rate of damage were 14.72 and 5.6$1{\mu}g/L$, respectively.

• Spatial Information Research
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• v.12 no.2
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• pp.151-163
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• 2004

This study aims to develop a standard protocol by which users can exchange data information efficiently between KOSDIC and GIS. The ultimate goal from this study is to propose a data exchange format using KOSIC. The background of this study is that GIS industry sector is vigorously developing linked to spatial information construction such as UIS, LIS, EIS, AM/FM through supporting by regional government institution. According to do, the format of data transformation becomes major issue. GIS data can easily transfer to CAD version but when CAD data convert to GIS format (DWG->DXF->SHP) cannot get high success rate due to errors and problems. In addition, CAD data feature is made from oriental structure which is made of point and line faeture so that GIS system is impossible to data transformation. In the reason, the biggest problem is discordance of symbolization in integration and standard of data format. By investigation the usability of this study, conclusion are drawn efficient alternative plan in data transformation. Though this wort we will be able to provide a better transformation of data conversion between CAD format and GIS format. Accordingly, it is of important to enrich the integrated construction information infrastructure, which accommodates ever-changing constructions environment.

• Environmental Engineering Research
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• v.15 no.2
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• pp.105-109
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• 2010

The European Union (EU) Water Framework Directive (WFD) (2000/60/EC) was transposed into Irish law by Statutory Instrument Nos. 722 of 2003, 413 of 2005 and 218 of 2009, which set out a new strategy and process to protect and enhance Ireland's water resources and water-dependent ecosystems. The Directive requires a novel, holistic, integrated, and iterative process to address Ireland's natural waters based on a series of six-year planning cycles. Key success factors in implementing the Directive include an in-depth and balanced treatment of the ecological, economic, institutional and cultural aspects of river basin management planning. Introducing this visionary discipline for the management of sustainable water resources requires a solemn commitment to a new mindset and an overarching monitoring and management regime which hitherto has never been attempted in Ireland. The WFD must be implemented in conjunction with a myriad of complimentary directives and associated legislation, addressing such key related topics as flood/drought management, biodiversity protection, land use planning, and water/wastewater and diffuse pollution engineering and regulation. The critical steps identified for river basin management planning under the WFD include: 1) characterization and classification of water bodies (i.e., how healthy are Irish waters?), 2) definition of significant water pressures (e.g., agriculture, forestry, septic tanks), 3) enhancement of measures for designated protected areas, 4) establishment of objectives for all surface and ground waters, and 5) integrating these critical steps into a comprehensive and coherent river basin management plan and associated programme of measures. A parallel WFD implementation programme critically depends on an effective environmental management system (EMS) approach with a plan-do-check-act cycle applied to each of the evolving six-year plans. The proactive involvement of stakeholders and the general public is a key element of this EMS approach.

• The Journal of Information Technology
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• v.4 no.2
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• pp.83-102
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• 2001

International Courier Service can be used for on campus pick-up and delivery of small items on a pre-arranged basis or on call. Same day service is available for important items at a minimal fee. As e-commerce develops, effective procurement and delivery become even more critical success factors, offering great opportunities to the transportation and logistics Industry in an e-Commerce World. Much of the logistics industry has developed, or is developing systems to operate in the new e-market to capture new electronic tailer clients and enhance relationships with current customers. Supply chain solutions based on EC links will eventually become standard, leaving some companies behind. fresh opportunities and reduced entry barriers to new competitors via e-commerce pose a major threat to the present logistics industry. supply chain systems developers and industry consultants that subcontract physical transport of goods to contractors may encroach on traditional logistics industry business. In this paper I tried to explain various aspects of the physical distribution service through international courier service in an e-commerce world and survey the logistics strategy of international courier service companies against development of electronic commerce based on our companies, logistics strategy.

• Korean Management Science Review
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• v.22 no.2
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• pp.109-133
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• 2005

The exponential growth of the on-line shopping mall has been the advent of buying and selling products and services over the internet. In these circumstances, this paper presents the importance of understanding and managing the purchasing behavior of on-line shopping mall customers. The main purpose of this research is to find out the antecedents of customer trust and to conceptualize and investigate the relationship between endogenous mediating variables(such as customer trust, attitude, loyalty, relationship involvement) and purchasing and/or repurchasing intention in internet shopping mall. The empirical findings are as follows : First, the three antecedents of customer trust( EC system characteristics, psychological propensity, and trustworthiness) had the positive effects on the formation of site trust. Second, we found out that there were direct or indirect relationships between the mediating variables and on-line purchasing and/or repurchasing intention. In Particular, the direct effects of customer attitude on customer loyalty and buying intention were rejected, but the indirect effects through relationship involvement were accepted. This means that the relationship marketing is probably more important for the success of internet shopping mall Third, there were no direct relationship between the mediating variables and the repurchasing intention, but most researches in the brick and mortar, the proposition are supported. This implies that repurchasing intention was intensified by the indirect path, such as site trust $\longrightarroe$ attitude $\longrightarroe$ involvement $\longrightarroe$ loyalty $\longrightarroe$ purchasing intention $\longrightarroe$ repurchasing intention. So, the internet marketers must make an effort not only to strengthen the direct casual linkage between them but also to consolidate the indirect connections leading to boost purchasing and repurchasing intention.

• Journal of the Economic Geographical Society of Korea
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• v.6 no.1
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• pp.119-144
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• 2003

This study attempts to figure out the impact of Information and communication technologies (ICTs) on spatial structure and to speculate on spatial strategies in the electronic economy from a geographical perspective. The unprecedented development of ICTs based on the explosive use of the Internet was enough to lead to the expectation that physical distance would not be a significant barrier in business activities. In fact, however, at least at a current stage, the development of ICTs has not automatically removed the inequality in spatial structure. The accessibility to electronic space is different by economic and social status within a country as well as between countries. The importance of place, locality, and place-specific assets has been strengthened in the global economy. Physical proximity is still of great importance because it helps to minimize transaction costs, to exploit place-specific social networks, and to accumulate credibility for successful businesses. Likewise, the development of electronic commerce such as B2B and B2C EC also does not necessarily result in the ignorance of place and locality. Rather, the recognition of the importance of spatial strategies is extremely important for the success in online businesses. As a conclusion, the spatial dimension becomes more important in the digital era for successful businesses and balanced regional developments than ever before. The need for the improvement of ICT infrastructures, the development of human resources, and the establishment of regional innovation systems in peripheral areas cannot be overemphasized even in the digital era.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.335-339
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• 2019

The white peach scale (Pseudaulacaspis pentagona) is a significant pest of trees belonging to the Rosaceae family. We investigated the effect of ten insecticides on hatching rate of first instar white peach scale larvae (crawlers). The insecticides are Dinotefuran WG, Benfuracarb WG, Pyrifluquinazon WG, Clothianidin SG, Buprofezin WP, Buprofezin+Imidacloprid SC, Buprofezin+Etofenprox WG, Buprofezin+Thiacloprid SC, Benfuracarb+Buprofezin WG, Acetamiprid+Buprofezin EC. We observed that several crawlers emerged in early May, with the average number being 45.7. Hatching period was approximately 14 days, and the hatching success rate was approximately 77.7%. Overwintering females produced an average of 58.7 eggs. All insecticides achieved 100% mortality in crawlers. Our results suggest that these insecticides can effectively control white peach scale when used at the crawler stage.