• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.211-219
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• 2004

A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces stric시y related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials. In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.

• Journal of the HCI Society of Korea
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• v.10 no.1
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• pp.19-27
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• 2015

As the mobile content industry is growing, mobile health (m-health) market is expanding based on various contents. It has developed in the way of utilizing health contents through mobile device such as smart phone among young people. This study aims to examine the usage of m-health application and factors of continuous usage among students in Seoul National University. The result is expected to provide a foundation for future health promotion programs utilizing m-health. The study analyzes the difference of application usage tendency based on demographic characteristic and the continuous usage, and compared the level of knowledge, attitude, belief, and practice (KABP) of mobile health application. 28% of the total sample population uses the application continuously, and their KABP level was higher than that of users that stopped using. This study goes beyond the previous studies of service satisfaction and acceptance analysis on the marketing level, and is meaningful in that it has analyzed the m-health application usage from the public health point of view.

• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.97-108
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• 2005

This study is to estimate differences, relationships and related factors of environmental risk perception and perceived benefit among residents and workers. A self-administered questionnaire survey using a structured instrument was carried out to residents and workers in industrial area during April, 2002. Total number of participants were 657 including 329 residents and 328 workers. Participants assessed environmental risk perception, self- assessed knowledge, trust in authorities and perceived benefit associated with 10 products manufactured in industrial area. There were difference in environmental risk perception, knowledge and trust in authorities and perceived benefit among residents and workers. Especially, trust in authorities and perceived benefit were statistically significant difference among residents and workers. Inverse relationships between environmental risk perception and perceived benefit have been observed for different products. In other words, the greater the perceived benefit, the lower the perceived risk, and vice versa. Factors mostly associated with participant's characteristics of environmental risk perception were age. marriage status (workers), education level (workers). There was statistically significant difference. Perceived benefit was statistically significant difference with sex, marriage status, residence duration, education level (workers). Related factors of environmental risk perception among residents and workers were age, trust in authorities. And factors affecting the perceived benefit were sex, age, education level (workers), and trust in authorities (workers). According to the results, people having high trust in the authorities perceived less risks than people having low in the authorities. To improve the communication of risk information, further study focus on assessment of experts, government and stakeholder in industrial area. Methodologies of this study can be used as the basis for investigating the structure of public perception of environmental products risks and benefit, designing a public information and risk communication program, and developing policy actions to improve acceptance.

• The Journal of the Korea Contents Association
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• v.16 no.9
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• pp.22-39
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• 2016

How to obtain the financial resources has not been sufficiently addressed, although the unification of Korea incurs enormous cost. This study explains what tax payers of Korea think with regard to the unification tax which is a contradictory issue as a financial resource. The authors analyzed demographic factors, an initial attitude to unification and tax system, and the degree of knowledge as independent variables affecting the intention to pay the unification tax. Furthermore, through the prospect theory, the authors found out how the attitudes of tax payers change by providing them with different messages according to whether they support or oppose the unification tax. The results showed that a group who are male, a group who are old, and a group with high income tend to support the unification and the unification tax more than others. And the results presents that a group who has more interests in both the unification and the unification tax and a group who has more knowledge about the unification and the tax system have more willingness to pay the unification tax than others. In addition, with regard to the persuasive effect of distinct message types, a message which conceals the cost of attitude change was demonstrated to be more effective than a message which emphasizes the benefit.

• The Journal of the Korean dental association
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• v.47 no.5
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• pp.291-296
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• 2009

Purpose : The aim of this studγ was to evaluate the patient's and dentist's perspective and knowledge on rapid human immunodeficiency virus screening test in dental setting. Material and Methods: In March 2009, 100 patients and 100 dentists at College of Dentistry, Yonsei University were provided an attitude assessment survey. Results : Results were analyzed for acceptance of testing and potential barriers. 94% of patients agreed to take a rapid HIV screening test and 77% of dentists were willing to provide the test to their patients. Also the current knowledge state of patients and dentists on HIV infection was not accurate as expected. Conclusion : Overall, dental clinic patients widely accepted the offer of rapid oral HIV screening. Rapid HIV screening test in the dental setting ran be an important option to increase the number of individuals who know their HIV status.

• The Journal of Korean Academic Society of Nursing Education
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• v.3
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• pp.26-33
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• 1997

Problem-Based Learning(PBL) is at the forefront of educational reform. The acceptance of PBL as an educational approach with wide application represents a major change in thinking about educational processes and their relationships to the wider community. In 1969, PBL as a method was introduced at the Medical School of McMaster University in Hamilton, Canada. The most important advantages in PBL are acquiring knowledge that can be retrieved and applied, learning to learn(self-directed learning) and learning to analyze and solve Problems. PBL is widely used within the sector where it had its origin, namely health profession education. A generally accepted starting point in the development of a problem-based curriculum is the set of professional competencies of future graduates, which describe the typical problems professionals have to deal with. Formulating learning objectives highly depends on the format and content of the presented problems. Contrary to that, in a classic course in higher education, it is customary that teachers express objectives in a compulsory subject matter. Curricula which advocate problem-based learning generally use case studies in the form of paper cases, simulations and real patients with the intention of stimulating classroom discussion of clinical and basic science concepts within a problem-solving framework. One goal of using paper cases is to stimulate the learning of basic science within a clinical situation. Through self-directed study the students solve problems and explore the psycho-social dimensions within the cases. The general outcome based on the program evaluation research of PBL is that PBL students respond positively about the learning experience. In summary, PBL is a curriculum design and a teaching/learning strategy which simultaneously develops higher order thinking and disciplinary knowledge bases and skills by placing students in the active role of practitioners(or problem solvers) confronted with a situation(ill-structured problem) which reflects the real world.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.539-542
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• 2006

According as acceptance an order results of plant industry increases, ability of plant project management is required and necessity about information technology is augmented. For required information technology, developing information present conditions that consist of partial or unit system of domestic plant companies by synthetic system, development of systematic plant information system that supply standard direction presentation, tools and know-how about information technology need. This study achieved basic research that set information strategy and target by reflect trend of such plant industry, analyze future IT technology trend, international information environment, policy trend etc. and execute SWOT analysis of plant information system through this and present confrontation ways. It is presented confrontation ways by SWOT analysis through this research; (1) Development of education contents that can come forth competent person of plant industry, (2) Practical use of communication means that can offer by real time about informations connected with plant, (3) Offer of knowledge contents that supply various and useful inside and outside of the country's plant knowledge

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1575-1588
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• 2017

In order to develop a domestic research roadmap for severe accidents, a special committee was established by the Korean Nuclear Society. One of the subcommittees discussed the characteristics and the relevant technical issues in the stages of fission product release and physical forms of radionuclide release and transport. The group members developed a tree to identify fission product release phenomena by tracing failures of individual defense-in-depth barriers and added possible countermeasures against failure. For each elemental issue, they searched for technical problems by examining the phenomena, accident management actions, and regulatory aspects relevant to the mitigation features for containment, including mitigation strategies against containment bypass accidents. Regulatory concerns, including the source term and the acceptance criteria for radionuclide release, were also considered. They identified further research needs regarding important technical issues based on the degree of the current knowledge level in Korea and in foreign countries, looking at the significance and urgency of issues and the expected research period required to reach an advanced level of knowledge. As a result, the group identified the 12 most important and urgent issues, most of which were expected to require mid-term and long-term research periods.

• The Journal of Advanced Prosthodontics
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• v.7 no.6
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• pp.437-445
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• 2015

PURPOSE. A survey was conducted to assess the impact of a TED-like educational session on participants' willingness to accept dental implant therapy. MATERIALS AND METHODS. Volunteers interested in having information about dental implant therapies were recruited and asked to complete a two-part survey before and after an educational session. The initial survey elicited demographic information, self-perceived knowledge on dental implants and willingness to this kind of treatment. A "TED-style" presentation that provided information about dental implant treatments was conducted before asking the participants to complete a second set of questions assessing the impact of the session. RESULTS. The survey was completed by 104 individuals, 78.8% were women and the mean age was $66.5{\pm}10.8$. Before the educational session, 76.0% of the participants refused dental implants mainly due to lack of knowledge. After the educational session, the rejection of dental implants decreased by almost four folds to 20.2%. CONCLUSION. This study proved that an educational intervention can significantly increase willingness to accept treatment with dental implants in a segment of the population who is interested in having information about dental implant therapy. Furthermore, educational interventions, such as TED-like talks, might be useful to increase popular awareness on dental implant therapy.

• Journal of Microbiology and Biotechnology
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• v.32 no.6
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• pp.681-698
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• 2022

The Nile tilapia Oreochromis niloticus, Atlantic salmon Salmo salar, rainbow trout Oncorhynchus mykiss, olive flounder Paralichthys olivaceus, common carp Cyprinus carpio, grass carp Ctenopharyngodon idella and rohu carp Labeo rohita are farmed commercially worldwide. Production of these important finfishes is rapidly expanding, and intensive culture practices can lead to stress in fish, often reducing resistance to infectious diseases. Antibiotics and other drugs are routinely used for the treatment of diseases and sometimes applied preventatively to combat microbial pathogens. This strategy is responsible for the emergence and spread of antimicrobial resistance, mass killing of environmental/beneficial bacteria, and residual effects in humans. As an alternative, the administration of probiotics has gained acceptance for disease control in aquaculture. Probiotics have been found to improve growth, feed utilization, immunological status, disease resistance, and to promote transcriptomic profiles and internal microbial balance of host organisms. The present review discusses the effects of single and multi-strain probiotics on growth, immunity, heamato-biochemical parameters, and disease resistance of the above-mentioned finfishes. The application and outcome of probiotics in the field or open pond system, gaps in existing knowledge, and issues worthy of further research are also highlighted.