• Convergence Security Journal
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• v.8 no.1
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• pp.35-42
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• 2008

While an information system and administration for an application that a user contacts with raise a head by an important problem, a system approach and methodology for administration are mentioned. Authentication technology of various configuration is used, but non-efficiency by complicated authentication administration and operation inappropriate use are for a successful expansion of various and new business of wire/wireless environment. In addition, under the mobile computer environment with different authentic method each other, it is difficult at all to expect flexible and continuous service. Under the ubiquitous computing environment, It is very important thing plan to research and develop compatibility and the side of variance authentication plan that preservation characteristics are helped. Hereby, This paper look around an requirement items and authority mechanism for the administration and the operation mechanism of the distributed authentication considering expansion possibility of the ubiquitous computing environment not only fixed computing environment but also mobile computing. In future, we expect it by can guide positive participation about distributed authentication technique of the genuine ubiquitous environment.

• Journal of Environmental Science International
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• v.26 no.9
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• pp.1013-1021
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• 2017

Exposure to Diesel Particulate Matter (DPM) potentially causes adverse health effects (e.g. respiratory symptoms, lung cancer). Due to a lack of data on Elemental Carbon (EC) exposure levels in underground copper ore mining (unlike other underground mining industries such as non-metallic and coal mining), this case study aims to provide individual miners' EC exposure levels, and information on their work practices including use of personal protective equipment. EC measurement was carried out during different work activities (i.e. drilling, driving a loader, plant fitting, plant operation, driving a Specialized Mining Vehicle (SMV)) as per NIOSH Method 5040. The copper miners were working 10 h/day and 5 days/week. This study found that the most significant exposures to EC were reported from driving a loader (range $0.02-0.42mg/m^3$). Even though there were control systems (i.e. water tanks and DPM filters) on the diesel vehicles, around 49.5% of the results were over the adjusted recommendable exposure limit ($0.078mg/m^3$). This was probably due to: (1) driver's frequently getting in and out of the diesel vehicles and opening the windows of the diesel vehicles, and (2) inappropriate maintenance of the diesel vehicles and the DPM control systems. The use of the P2 type respirator provided was less than 19.2%. However, there was no significant difference between the day shift results and the night shift results. In order to prevent or minimize exposure to EC in the copper ore mine, it is recommended that the miners are educated in the need to wear the appropriate respirator provided during their work shifts, and to maintain the diesel engine and emission control systems on a regular basis. Consideration should be given to a specific examination of the diesel vehicles' air-conditioning filters and the air ventilation system to control excessive airborne contaminants in the underground copper mine.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.7
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• pp.31-36
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• 2004

In comparison with in-plane lasers, predicting the output power and differential quantum efficiency of Vertical-Cavity Surface-Emitting Lasers(VCSELs) is very difficult due to the distributed Bragg reflector(DBR) layers. Therefore, effective cavity model and transfer matrix method have been adapted in order to calculate the output power and differential quantum efficiency The effective cavity model is inappropriate to calculate output power and differential quantum efficiency while it is practically adequate to calculate the threshold gain and threshold current density The reason is that the effective cavity model can not take account of the absorption in GaAs stack layer right below the metal aperture. In this paper, we have compared the threshold current and differential quantum efficiency calculated by using transfer matrix method with effective cavity model and we have made a study of the validity of the effective cavity model. Finally, we have confirmed the versatility of the transfer matrix method with these studies.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.619-631
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• 2009

The purpose of this study was to provide basic information to school foodservice employees so that they can meet their professional responsibilities by understanding the relationship of job burnout, job engagement, job stress and level of job satisfaction and analyze the influence between these factors according to the general characteristics of the employees. The subjects included employees at 426 school foodservices in Busan. The mean job engagement was significantly different in the reason that cooks chose this profession(p<0.05), and readiness to quit(p<0.001). The mean job stress was significantly different in different age groups(p<0.01), cooking certification(p<0.01), reason that cooks chose this profession(p<0.01), and readiness to quit(p<0.05). The mean job stress was significantly different in the reason cooks chose this profession(p<0.01), and readiness to quit(p<0.05). In terms of the level of satisfaction of coworkers, the subfactor of job burnout, 'self-confidence' and 'achievement' had positive influences (p<0.01) and for the level of satisfaction of the work, it had positive influences on 'achievement'(p<0.01) and negative influences on 'exhaustion' (p<0.01). In terms of the level of satisfaction of co-workers and work, the subfactor of job engagement, 'absorption' had positive influences(p<0.01). Among the level of job satisfaction, for the level of satisfaction of pay, the subfactor of job stress, 'unstable job' had negative influences(p<0.01) and 'role conflict' had positive influences(p<0.05). For the level of satisfaction of co-workers, the subfactor of job stress, 'role conflict' had negative influences(p<0.01), and for the level of satisfaction of work, 'inappropriate circumstance' and 'unstable job' had negative influences (p<0.01).

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.10
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• pp.22-28
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• 1998

Signal transmission and crosstalk of coupled bondwires buried in plastic packages are analyzed using the Method of Moments and the Fourier Transform algorithm. It is also shown that the quasi-static crosstalk model of SPICE is inappropriate for designing the high-speed plastic packages. Plastic packaging material, increasing the self and mutual capacitances, is found to be helpful for the signal transmission integrity due to the dielectric compensation effect. However, it is also observed that the plastic material increases the crosstalk due to the radiation-enhanced mutual coupling effect. By investigating the geometrical and material dependence of the pulse transmission and crosstalk, it is found that the radiation-enhanced coupling effect is significant for most of typical bondwire geometries and plastic package materials. These calculation results can be effectively used for designing plastic packages of high-speed digital IC's and monolithic RFIC's.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.69-79
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• 2015

As the distribution rate of a smart phone which can actualize even augmented reality is getting higher, the application scope of a smart phone is sharply increasing. However, in spite of various functions of it, there is still lack of learning app. Mobile equipments can bring no spatial-temporal restriction of learning to a learner, but they can tempt a learner into inappropriate spaces. In this sense, learning app is necessarily needed to motivate and keep learner's inner desire. This thesis suggested considerations when learning mobile app is designed by analyzing motivation strategy of ARCS Theory and UI of web based contents. Also, a design method of mobile learning app was suggested based on a procedural model of mobile learning app adapting ARCS Theory.

• Journal of the Korea Safety Management & Science
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• v.16 no.3
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• pp.195-200
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• 2014

Occupational fatal injury rate per 10,000 population of Korea is still higher among the OECD member countries. To prevent fatal injuries, the causes of accidents including human error should be analyzed and then appropriate countermeasures should be established. There was an severe converter furnace accident resulting in five people death by chocking in 2013. Although the accident type of the furnace accident was suffocation, many safety problems were included before reaching the death of suffocation. If the safety problems are reviewed throughly, the alternative measures based on the review would be very useful in preventing similar accidents. In this study, we investigated the converter furnace accident by using human error analysis and accident scenario analysis. As a result, it was found that the accident was caused by some human errors, inappropriate task sequence and lack of control in coordinating work by several subordinating companies. From the review of this case, the followings are suggested: First, systematic human error analysis should be included in the investigation of fatal injury accidents. Second, multi man-machine accident scenario analyis is useful in most of coordinating work. Third, the more provision of information on system state will lessen human errors. Fourth, the coordinating control in safety should be performed in the work conducting by several different companies.

• Journal of the Korean Society of Safety
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• v.33 no.1
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• pp.66-72
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• 2018

This study analyses the types, related operations, facilities, and causes of chemical accidents in Korea based on the RISCAD classification taxonomy. In addition, human error analysis was carried out employing different human error classification criteria. Explosion and fire were major accident types, and nearly half of the accidents occurred during maintenance operation. In terms of related facility, storage devices and separators were the two most frequently involved ones. Results of the human error-based analysis showed that latent human errors in management level are involved in many accidents as well as active errors in the field level. Action errors related to unsafe behavior leads to accidents more often compared with the checking behavior. In particular, actions missed and inappropriate actions were major problems among the unsafe behaviors, which implicates that the compliance with the work procedure should be emphasized through education/training for the workers and the establishment of safety culture. According to the analysis of the causes of the human error, the frequency of skill-based mistakes leading to accidents were significantly lower than that of rule-based and knowledge based mistakes. However, there was limitation in the analysis of the root causes due to limited information in the accident investigation report. To solve this, it is suggested to adopt advanced accident investigation system including the establishment of independent organization and improvement in regulation.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.3
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• pp.87-106
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• 2013

Objectives We will provide basic information on bee venom clinical tests and aid the practical use of bee venom in such tests, through examination of RCT research related to bee venom that was reported domestically. Methods We collected 365 articles on Bee venom study result from the OASIS system using the Keyword 'bee venom, apitoxin, apitherapy, bee sting'. The initially selected theses were primarily screened for clinical research. Out of these, case studies and non randomized controlled trial (non-RCT) were ruled out. As a result, 39 studies of randomized controlled trial (RCT) research were chosen as the subjects of study. Results RCT research related to bee venom was first presented in 2003, and 39 studies have been published until 2012. 18 studies were tests to confirm the effectiveness of bee venom, 7 studies were comparisons between SBV and BV, and 13 studies were comparisons with other types of treatment. Research conducted through appropriate randomization methods were 20 studies, and inappropriate randomization methods were used in 19 studies. In therms of Jadad score, 12 studies received 4~5 points, 15 studies received 1-3 points, and 12 studies received zero point. Conclusions In order to assure good quality RCT research, appropriate guidelines should be provided, and proper evaluation standards should be established. In-depth study is needed concerning the difference of responses to treatment according to the types of treatment received. A standardization of treatment should be reached as a result.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.6
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• pp.378-387
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• 2007

To enhancing the exercise effect, exercise management systems are introduced and generally used. They create the proper exercise program through exercise prescription after determining the personal body status. When the exercise programs are created, they will consider $2weeks{\sim}3months$ period. And, existing exercise programs cannot respect with personal exercise habits or exercise period which are changing variedly. If exercise period is long, it can be caused inappropriate exercise about user current status. To solve these problems in legacy systems, this paper proposes a Context Aware Exercise Model (CAEM) to provide the exercise program considering the user context. Also, we implemented that as Intelligent Fitness Guide (IFG) System. The IFG system is selectively received necessary measurement values as input values according to user's context. If exercise kinds, frequency and strength of user are changing, that system creates the exercise program through exercise optimization algorithm and exercise knowledge base. As IFG is providing the exercise program in a real time, it can be managed the effective exercise according to user context.