• The Journal of Advanced Prosthodontics
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• v.12 no.3
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• pp.124-130
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• 2020

PURPOSE. The aim of this in vitro study was to evaluate the effect of sintering procedures on marginal discrepancies of fixed partial metal frameworks fabricated using different sintering-based computer-aided design and computer/aided manufacturing (CAD/CAM) techniques. MATERIALS AND METHODS. Forty resin die models of prepared premolar and molar abutment teeth were fabricated using a three-dimensional (3D) printer and divided into four groups (n = 10) according to the fabrication method of metal frameworks used: HM (via hard milling), SM (via soft metal milling), L25 (via direct metal laser melting [DMLM] with a 25 ㎛ layer thickness), and L50 (via direct DMLM with a 50 ㎛ layer thickness). After the metal frameworks were fabricated and cemented, five vertical marginal discrepancy measurements were recorded in each site (i.e., buccal, facing the pontic, lingual, and facing away from the pontic) of both abutment teeth under a stereomicroscope (×40). Data were statistically analyzed at a significance level of 0.05. RESULTS. No statistically significant differences (P>.05) were found among the four axial sites of metal frameworks fabricated by sintering-based CAD/CAM techniques. The HM and L25 groups showed significantly (P<.001) lower marginal discrepancy values than the SM and L50 groups. CONCLUSION. Marginal discrepancy in the sites facing the pontic was not influenced by the type of sintering procedure. All fabrication methods exhibited clinically acceptable results in terms of marginal discrepancies.

• Convergence Security Journal
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• v.23 no.1
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• pp.19-25
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• 2023

The current network environment provides a real-time interactive service from an initial one-way information prov ision service. Depending on the form of web-based information sharing, it is possible to provide various knowledge a nd services between users. However, in this web-based real-time information sharing environment, cases of damage by illegal attackers who exploit network vulnerabilities are increasing rapidly. In particular, for attackers who attempt a phishing attack, a link to the corresponding web page is induced after actively generating a forged web page to a user who needs a specific web page service. In this paper, we analyze whether users directly and actively forge a sp ecific site rather than a passive server-based detection method. For this purpose, it is possible to prevent leakage of important personal information of general users by detecting a disguised webpage of an attacker who induces illegal webpage access using traceback information

• The Journal of Society for e-Business Studies
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• v.18 no.1
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• pp.33-55
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• 2013

Information sharing behavior in the Internet has raised much interest. Recently, social network sites provide a new information sharing channel for the users who want to connect with others based on common social background or tastes. Especially, we focus that a social network site becomes one of major routes for information sharing about socially influential issues. Therefore, studying how information is diffused via a social network site may give theoretically, practically significant implication. Based on the assertion, we investigated user's behavior to mediate other user's information messages. We define information mediating behavior as concurrent actions of filtering and distributing behavior of the digital content that is originated from one of the connected users. In this study, we intended to understand the effects of information mediating behavior, and tried to understand characteristics of re-mediating of previously mediated information. Using an agent-based simulation model, we found that information mediating behavior increased the extent of information diffusion significantly. In addition, even a small degree of mediating probability could boost up the level of information diffusion in the case of a re-mediating condition. We believe that those findings provide remarkable insight of research and business application on both of information sharing and diffusion in a social network site.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.2
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• pp.404-420
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• 2021

In this paper, an automatic system of locating the indoor area with weak or no mobile signal was proposed and demonstrated experimentally by using the Internet of Things (IoT) technology. Nowadays, the technicians of mobile services providers need to go along with numerous heavy equipment to measure and record the mobile signal strength at outside environment. Recently, there are systems proposed to do such measurement at outdoor area by using the IoT technology automatically. However, these works could not be applied in the indoor area since there are difficulties to do the indoor mapping and positioning. In this work, the Bluetooth Low Energy (BLE) was used to tackle these two difficulties. After a proper placement of BLE in the testing site, while the technician walk around with a handheld analyzer, the data can be obtained accordingly for further analysis in the proposed system which includes the construction of floor plan, detection of mobile signal strength and suggestion of indoor base stations. The gift wrapping and centroid algorithms were used during the analysis. The experimental results showed that the proposed system successfully demonstrated the indoor mapping, positioning of weak mobile signal area and suggestion of indoor base stations for the normal rectangular rooms with an area of 100 m² on single floor.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.127-139
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• 1993

In order to obtain basic information for the extablishment of effectivce industrial safety programmes in heavy industries & construction companies, accident records for 366 injured workes were collected from January, 1989 to December 1991 and analyzed. The results were as follows : 1. The over-all incidence rate of industrial accidents was 2.98% per year 2. Accidents were common in the workers who are in thirties and twenties. 3. According to the duration of services, the workers with jobs on above than 3 years was the most frequent victims (64.2%) 4. According to the view point of working time, the highest incidence was observed just before the end of the work (17:00-19:00). 5. According to the month of year, the incidence was higher in August(14.0%) and May(14.2%), and lowest in January (3.3%) 6. The most common type of accidents was overexertion (24.9%). 7. According to the job, the highest incidence was observed fabrication. 8. According to the site of injuries, the incidence was higher the truck (27.0%) and fingers (25.1%).

• International Journal of Contents
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• v.7 no.2
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• pp.26-31
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• 2011

People with obesity or over-weight need nutritional intervention to reduce their weight, because weight loss reduces the incidence rate of chronic diseases such as hypertension, type II diabetes, cardiovascular diseases and cancer in obese people. This study was to develop a system for individualized weight control program available both for wired and wireless internet users. This system is especially useful to users carrying wireless internet mobile device. If they input their physical information (height, weight and waist circumference) and mineral levels measured by hair tissue mineral analysis, the system provides evaluation of their health status and metabolic related functions such as endocrine and carbohydrate tolerance. Based on these evaluations, food menus are then offered to them to manage their health status and to improve their metabolic related physiological functions in a personalized way. The system also provides more information for recommended foods, such as nutritional information, food ingredients, recipes, and videos related to cooking. Bibimbap was selected as an example dish for customized contents for mobile web. Bibimbap is one of the most well-known Korean traditional dishes prepared with various kinds of ingredients including several different kinds of vegetables, meat, and egg so that it is a low calorie dish as well as a well-balanced diet. Therefore, this system developed in this study allows the mobile users to access web site through wired wireless internet everywhere and provides a customized content to the users to manage their weight and finally to achieve a desirable weight.

• The Korean Journal of Air & Space Law and Policy
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• v.5
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• pp.101-118
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• 1993

Generally there is no law and liability system which applies particulary to commercial space ventures. There are several international treaties and national statutes which deal with space ventures, but their impact on the liability of commercial space ventures has not been significant. Every state law in the United States will impose both tort and contract liability on those responsible for injuries or losses caused by defective products or by services performed negligently. As with the providers of other products and services, those who participate in commercial space ventures have exposure to liability in both tort and contract which is limited to the extent of the resulting damage The manufacturer of a small and cheap component which caused a satellite to fail to reach orbit or to operate nominally has the same exposure to liability as the provider of launch vehicle or the manufacturer of satellite into which the component was incorporaded. Considering the enormity of losses which may result from launch failure or satellite failure, those participated in commercial space ventures will do their best to limit their exposure to liability by contract to the extent permitted by law. In most states of the United States, contracts which limit or disclaim the liability are enforceable with respect to claims for losses or damage to property if they are drafted in compliance with the requirements of the applicable law. In California an attempt to disclaim the liability for one's own negligence will be enforceable only if the contract states explicitly that the parties intend to have the disclaimer apply to negligence claims. Most state laws of the United States will refuse to enforce contracts which attempt to disclaim the liability for gross negligence on public policy grounds. However, the public policy which favoured disclaiming the liability as to gross negligence for providers of launch services was pronounced by the United States Congress in the 1988 Amendments to the 1984 Commercial Space Launch Act. To extend the disclaimer of liability to remote purchasers, the contract of resale should state expressly that the disclaimer applies for the benefit of all contractors and subcontractors who participated in producing the product. This situation may occur when the purchaser of a satellite which has failed to reach orbit has not contracted directly with the provider of launch services. Contracts for launch services usually contain cross-waiver of liability clauses by which each participant in the launch agrees to be responsible for it's own loss and to waive any claims which it may have against other participants. The crosswaiver of liability clause may apply to the participants in the launch who are parties to the launch services agreement, but not apply to their subcontractors. The role of insurance in responding to many risks has been critical in assisting commercial space ventures grow. Today traditional property and liability insurance, such as pre-launch, launch and in-orbit insurance and third party liability insurance, have become mandatory parts of most space projects. The manufacture and pre-launch insurance covers direct physical loss or damage to the satellite, its apogee kick moter and including its related launch equipment from commencement of loading operations at the manufacture's plant until lift off. The launch and early orbit insurance covers the satellite for physical loss or damage from attachment of risk through to commissioning and for some period of initial operation between 180 days and 12 months after launch. The in-orbit insurance covers physical loss of or damage to the satellite occuring during or caused by an event during the policy period. The third party liability insurance covers the satellite owner' s liability exposure at the launch site and liability arising out of the launch and operation in orbit. In conclusion, the liability in commercial space ventures extends to any organization which participates in providing products and services used in the venture. Accordingly, it is essential for any organization participating in commercial space ventures to contractually disclaim its liability to the extent permitted by law. To achieve the effective disclaimers, it is necessary to determine the applicable law and to understand the requirements of the law which will govern the terms of the contract. A great deal of funds have been used in R&D for commercial space ventures to increase reliability, safety and success. However, the historical reliability of launches and success for commercial space ventures have proved to be slightly lower than we would have wished for. Space insurance has played an important role in reducing the high risks present in commercial space ventures.

• The Research Journal of the Costume Culture
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• v.23 no.3
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• pp.384-399
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• 2015

The purpose of this study is to empirically investigate consumers' clothes shopping orientation factors and perceived risk factors affecting the purchase intention for fashion products in social commerce. For this study, questionnaires were given to 500 adults in their 20s~30s who had experience of using social commerce related to general products or services. To analyze the results of this study, we conducted descriptive analysis, factor analysis, reliability analysis, a chi-square independence test, and hierarchical regression analysis using SPSS 18.0. The results were as follows. First, social commerce users'clothes shopping orientations were classified into the pursuit of pleasure, brand, fashion innovation, trend, and utility, and the perceived risks were classified into the risks related to products, consumer service, loss of purchase opportunity, confidence in the web site, economy, and security. Second, clothes shopping orientation factors and perceived risk factors had a somewhat significant influence on the purchase intention for fashion products. Third, there was a significant difference between sexes regarding the influences of the clothes shopping orientation factors and perceived risk factors for the purchase intention of fashion products. Finally, this study aims to provide useful information for fashion companies to enable them to establish specific strategies that can influence consumers'purchase behaviors through social commerce.

• Journal of Information Technology Applications and Management
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• v.17 no.2
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• pp.71-90
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• 2010

Electronic learning(or e-learning) has created hype for companies, universities, and other educational institutions. It has led to the phenomenal growth in the use of web-based learning and experimentation with multimedia, video conferencing, and internet-based technologies. Many researchers are interested in the factors that affect to the performance of e-learning or e-learning services. In this sense, this study is aimed at proposing e-learning system reuse prediction models in which e-learner intention to reuse influence factors(i.e., system accessibility, system stability, information clarity, information validity, self-regulated efficacy, computer self-efficacy, perceived usefulness, perceived ease of use, flow, and parental expectation) affect e-learner intention to reuse positively. A web survey was conducted for the full members of the e-learning education institute A in Seoul, Republic of Korea, an exclusive e-learning company that provides real time video lectures via the desktop conferencing system. The web survey was conducted for 20 days from November 5, 2009, through the e-learning web site of the company A. In this study, three data mining techniques were used : the multivariate discriminant analysis, CART, and C5.0 algorithm. This study was conducted to provide the e-learning service providers, e-learning operators, and contents developers with marketing and management strategies for improving the e-learning service companies, based on the data mining analysis results.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.395-402
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• 2017

Social network service provides an excellent platform for people seeking for advices. This research analyzed the effect of rational and emotional response and social distance on people's acceptance for advices online by the construal level theory. An experiment was completed to test the relationship between advisers and questioners and verify the content of online feedback would influence people's acceptance for advices on social network site. The online response included emotional advice and rational advice. Social distance between advisers and questioners was divided to close social distance condition and distant social distance condition. The study showed: (1) comparing with emotional advice, rational advice had a higher persuasive effect in both close and distant social distance conditions; (2) the impact of feedback from people with close social distance was stronger than the impact of the advices from people with distant social distance; (3) there existed an interaction effect between social distance and affective advice. The results revealed that the adviser's affective expression and relationship with the questioner would interactively impact the online persuasive effect.