• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.5
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• pp.975-982
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• 2006

To cope with the recent developments of info-communication technology and information infrastructure, and in particular, to respond to the environment of wire and wireless communication integration, and also to overcome the limit of the existing web-based Port-MIS, the Ministry of Maritime Affairs and Fisheries is developing a mobile Port-MIS public service system (hereinafter referred to as a mobile Port-MIS). Accordingly, this study analyzes the current situation of the mobile Port-MIS that is under operation of the lust stage, finding out the problems, and suggesting new measures to activate the mobile Port-MIS. We expect this study will be able to suggest a guideline to the government institutions or other related organizations that plan to introduce a mobile technology in the near future.

• Journal of Information Technology Services
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• v.6 no.3
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• pp.69-86
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• 2007

As most of firms related with P2P services change their free services into fee-charging services, the problems of intellectual property rights are solved to satisfactory extent. Accordingly, P2P systems become more popular with the general public. In this respect, it is thought to be very important to research on the critical factors affecting usage of P2P systems. Although it is strongly expected that the characteristics of users activities in virtual communities affect the intention to re-use P2P systems, relatively few attention have been paid to this question. Therefore, this paper is to present empirical evidence to explain how the characteristics of users activities in virtual communities affect re-use intention of P2P services. The theoretical contribution of this study is that the characteristics of users activities in virtual communities is theoretically derived from the comprehensive literature review and the logical reasoning, and that the research model of the relationship between the users activities' characteristics in virtual community and the re-use intention of P2P services is proposed and empirically validated, which is expected to expand explaining power of the TAM(Technological Acceptance Model). Also, the practical implication is to provide the guideline to support the successful strategic planning for development and.operation of P2P services through the virtual communities.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.3
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• pp.105-113
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• 2017

Considered as the "new normal" mode of learning, BL has become popular in recent years especially in University education. BL is defined as a learning approach that combines e-learning and face-to-face classroom learning. BL allows for more interactive and reflective learning environment resulting in enhancing learner-directed learning. The adoption of BL in university has made it significant to probe the crucial determinants that would entice instructors and learners to use BL and enhance learning satisfaction. The primary purpose of this study is to investigate the affecting factors of the satisfaction of BL in universities in terms of leaner's aspects. Learner's role is very important in BL, because learner should self-directed study for effective performance and satisfaction in BL environment. Based on prior studies motivation, self-efficacy, and educational expectancy were identified as affecting factors of satisfaction in BL. According to the result of multiple regression, all factors(motivation, self-efficacy, and educational expectancy) were found to be significantly related to the learner's satisfaction in BL. It can provide practical guideline on effective operation strategy for BL in universities.

• Transactions of Materials Processing
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• v.17 no.4
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• pp.278-283
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• 2008

This paper concerns the die face design for a heat protect panel aided by the finite element forming analysis in order to eliminate the surface defect and to improve the surface quality. The CAE procedure of the stamping process is introduced in order to reveal the reason of surface inferiorities and to improve surface quality. Complicated shape of the product induces the surface inferiorities such as wrinkling due to the insufficient restraining force of the forming blank and the non-uniform contact of the blank with the tools. This paper proposes a new guideline for the die design which includes the modification of tool shapes and addition of the draw-beads on the tool surface for ensuring the increased the restraining force with the uniform contact condition. The effectiveness of the proposed design is verified by the forming analysis and is confirmed by the tryout operation in the press shop. The analysis and test results show that the modified process parameters such as tool shapes and draw-beads can reduce the tendency of wrinkling and improve surface quality.

• Journal of Chest Surgery
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• v.26 no.11
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• pp.845-850
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• 1993

Post-Pneumonectomy Empyema[PPE] is a relatively uncommon but serious complication. And the management of it remains a disturbing and controversial area in the field of general thoracic surgery. Many methods have described and have had varying degrees of success. For the purpose of providing the guideline for management of post-pneumonectomy empyema, we reviewed our experiences of treatment of PPE from January 1985. to December 1992. There were 17 cases, which consist 7.9% of all pneumonectomy cases for that period. There were 13 male and 4 female patients with mean age of 47.1$\pm$ 16.2 yrs old. Both chest has the same incidence. The most common disease for prior pneumonectomy was tuberculosis, but the PPE was the most frequently occurred in empyema. The duration between pneumonectomy and PPE was 44.7 $\pm$81.1 months, where 58.8% of patients occurred within 1 month. Fever was the most frequent complaint and wound dischrge was detected in less than half of patients. There were 2 in-hospital mortalities.Mostly, in 13 cases, we did Eloesser operation. Five of them could finish second Clagett procedure, but one had recurrence. Four bronchopleural fistular patients underwent 3 single stage muscle flap closure and 1 direct closure with modified Clagett procedure. None had recurrence. Mean follow-up duration is 30.9\ulcorner22.3 months. There was 1 late death which was not related to PPE but to Malignancy recurrence.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.759-763
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• 2006

The World Health Organization(WHO) has recommended population of sleep disturbance as one of the environmental health indicators. But the percentage of respondents who felt highly sleep disturbed, that is, %HSD can???thave application to sleep disturbance from instantaneous noise. Therefore, this study has been carried out to present the technique for assessing sleep disturbance on instantaneous noise quantitatively. The study of sleep disturbance on night time instantaneous railway noise has been undertaken. Noise monitor has been in operation from 22 hours to 7 hours during 6 nights at 12 locations. To assess instantaneous noise induced sleep disturbance, it was decided to measure body movement by actiwatch. %motility was used as indicators of sleep disturbance. %motility is the expected value of probability of motility value during 7 epochs (105s) of any noise event. The measures of instantaneous motility have been related to measures of instantaneous railway noise events. The relationship shows that %motility is a good predictor for assessing sleep disturbance and Korean is more sensitive to noise than European although the railway noise have been considered in this study. This study can be extended to assessing long-term sleep disturbance and give a guideline far policy decision.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.1096-1110
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• 2014

Whipping/springing research started in the 50'ies. In the 60'ies inland water vessels design rules became stricter due to whipping/springing. The research during the 70-90'ies may be regarded as academic. In 2000 a large ore carrier was strengthened due to severe cracking from North Atlantic operation, and whipping/springing contributed to half of the fatigue damage. Measurement campaigns on blunt and slender vessels were initiated. A few blunt ships were designed to account for whipping/springing. Based on the measurements, the focus shifted from fatigue to extreme loading. In 2005 model tests of a 4,400 TEU container vessel included extreme whipping scenarios. In 2007 the 4400 TEU vessel MSC Napoli broke in two under similar conditions. In 2009 model tests of an 8,600 TEU container vessel container vessel included extreme whipping scenarios. In 2013 the 8,100 TEU vessel MOL COMFORT broke in two under similar conditions. Several classification societies have published voluntary guidelines, which have been used to include whipping/springing in the design of several container vessels. This paper covers results from model tests and full scale measurements used as background for the DNV Legacy guideline. Uncertainties are discussed and recommendations are given in order to obtain useful data. Whipping/springing is no longer academic.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2207-2212
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• 2008

The next generation of Korean high-speed train under development will be designed for the maximum operating speed of 350km/h and maximum speed of 400km/h. This high-speed operation may cause the noise and vibration problems around tunnel exit due to the higher micro-pressure wave than present level. In this study, the nose shape optimization was conducted for the countermeasure against these problems. Axi-symmetric solver was used for numerical simulation, and response surface was used for efficiency of optimization process. Also the multi-step optimization was conducted to find out more accurate optimal shape. Through these analysis and optimization, it was found out that the optimal nose shapes for minimization of micro-pressure wave are definitely different along the nose length variation. And the mechanism of micro-pressure wave reduction was closely investigated by the analysis of generation process of compression wave in tunnel. The results are expected to be used as design guideline for performance improvement of the next generatin of Korean high-speed train.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.4
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• pp.318-324
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• 2005

The objectives of this paper are to study the heat transfer characteristics on enhanced surfaces, to develop experimental correlations of friction factor and Nusselt number, and to provide a guideline for optimum operation conditions at low temperature boiling for practical refrigeration applications. The working fluid (water, EG $30\%$) flows inside the enhanced tube and R134a boils on the outer surface. Two different types of Turbo-B tubes (Tube I and Tube II) are tested in the present study. The results show that Tube I gives a higher heat transfer coefficient with higher friction factor than Tube II. The present study provided experimental correlations for friction factor and heat transfer coefficient with error bands of ${\pm}5\%\;and\;{\pm}\;15\%$, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.231-239
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• 2014

This paper represents a method of existing building energy simulation using energy audit data. Energy audit must be carried out for reasonable analysis, because characteristics of existing buildings such as efficiency of fan, pump, flow rate, pressure, COP and operating schedule could be changed during the building operation. These building characteristics should be measured to estimate actual energy consumption of the existing building. In this study, we conducted energy audit and calculated energy savings for a 7-stories building as a case-study. The energy audit data were used to calibrate the building model of EnergyPlus simulation. Baseline model validated according to M&V guideline index. As a result, building characteristics are significant parameters making a big impact on energy savings in existing buildings.