• Geomechanics and Engineering
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• v.36 no.3
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• pp.231-245
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• 2024

In recent decades, the protection and vulnerability of civil structures under explosion loads became a critical issue in terms of security, which may cause loss of lives and structural damage. Concrete retaining walls also restrict soils and slopes from displacements; meanwhile, intensive temporary loading may cause massive damage. In the current study, the modified Johnson-Holmquist (also known as J-H2) material model is implemented for concrete materials to model damages into the ABAQUS through user-subroutines to predict the blasting-induced concrete damages and volume strains. For this purpose, a 3D finite-element model of the concrete retaining wall was conducted in coupled Eulerian-Lagrangian simulation. Subsequently, a blast load equal to 500 kg of TNT was considered in three different positions due to UFC 3-340-02. Influences of the critical parameters in smooth blastings, such as distance from a free face, position, and effective blasting time, on concrete damage rate and destroy patterns, are explored. According to the simulation results, the concrete penetration pattern at the same distance is significantly influenced by the density of the progress environment. The result reveals that the progress of waves and the intensity of damages in free-air blasting is entirely different from those that progress in a dense surrounding atmosphere such as soil. Half-damaged elements in air blasts are more than those of embedded explosions, but dense environments such as soil impose much more pressure in a limited zone and cause more destruction in retaining walls.

• The Korean Journal of Air & Space Law and Policy
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• v.25 no.2
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• pp.163-199
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• 2010

A frequent flyer program is a loyalty program offered by many airlines. Typically, airline customers enrolled in the program accumulate frequent flyer miles corresponding to the distance flown on that airline or its partners. There are other ways to accumulate miles. In recent years, more miles were awarded for using co-branded credit and debit cards than for air travel. Acquired miles can be redeemed for free air travel; for other goods or services, such as travel class upgrades, airport lounge access or priority bookings. The first modern frequent flyer program was created Texas International Airlines in 1979. This program was also adopted in Korean Air in 1984. Since then, the mileage programs have grown enormously. As of June 2009, the total member of two national airlines in Korea had been over thirty million. However, accumulated miles could be burden of airlines, because the korean corporations should record the annual financial report the accumulate mileage on a liability account by 'the international financial report standards(IFRS)' next year. The korean airlines need to minimize the accumulated miles, so that for instance Korean Airlines SKYPASS-miles expire 5 years after being earned. It means that miles earned on or after July 2008 will expire after five years if unredeemed. Thus, this paper attempt to analyze the unfairness of the mileage rules of korean airlines by examining a specific portion of the conditions relating to consumer protection, because many mileage users has difficulties using mileage programs and complained the amendment of the mileage rules. In conclusion, the contemporary mileage rules in Korea are rather unsatisfactory, because airlines is not only recognizing a mileage into a kind of benefit but also denying inheritance of mileage and the legal nature of mileage as a property right. It is necessary to amend relevant mileage rules in view of consumer protection, because air mileage is not simple benefit but a right of mileage user.

• Information Systems Review
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• v.14 no.3
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• pp.75-97
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• 2012

Fostering trusting belief in financial transactions is a challenging task in Internet banking services. Authenticated Certificate had been regarded as an effective method to guarantee the trusting belief for online transactions. However, previous research claimed that this method has some loopholes for such abusers as hackers, who intend to attack the financial accounts of innocent transactors in Internet. Two types of methods have been suggested as alternatives for securing user identification and activity in online financial services. Control transparency uses information over the transaction process to verify and to control the transactions. Outcome feedback, which refers to the specific information about exchange outcomes, provides information over final transaction results. By using these two methods, financial service providers can send signals to involved parties about the robustness of their security mechanisms. These two methods-control transparency and outcome feedback-have been widely used in the IS field to enhance the quality of IS services. In this research, we intend to verify that these two methods can also be used to reduce risks and to increase the security protections in online banking services. The purpose of this paper is to empirically test the effects of the control transparency and the outcome feedback on the risk perceptions in Internet banking services. Our assumption is that these two methods-control transparency and outcome feedback-can reduce perceived risks involved with online financial transactions, while increasing perceived trust over financial service providers. These changes in user attitudes can increase the level of user satisfactions, which may lead to the increased user loyalty as well as users' willingness to pay for the financial transactions. Previous research in IS suggested that the increased level of transparency on the process and the result of transactions can enhance the information quality and decision quality of IS users. Transparency helps IS users to acquire the information needed to control the transaction counterpart and thus to complete transaction successfully. It is also argued that transparency can reduce the perceived transaction risks in IS usage. Many IS researchers also argued that the trust can be generated by the institutional mechanisms. Trusting belief refers to the truster's belief for the trustee to have attributes for being beneficial to the truster. Institution-based trust plays an important role to enhance the probability of achieving a successful outcome. When a transactor regards the conditions crucial for the transaction success, he or she considers the condition providers as trustful, and thus eventually trust the others involved with such condition providers. In this process, transparency helps the transactor complete the transaction successfully. Through the investigation of these studies, we expect that the control transparency and outcome feedback can reduce the risk perception on transaction and enhance the trust with the service provider. Based on a theoretical framework of transparency and institution-based trust, we propose and test a research model by evaluating research hypotheses. We have conducted a laboratory experiment in order to validate our research model. Since the transparency artifact(control transparency and outcome feedback) is not yet adopted in online banking services, the general survey method could not be employed to verify our research model. We collected data from 138 experiment subjects who had experiences with online banking services. PLS is used to analyze the experiment data. The measurement model confirms that our data set has appropriate convergent and discriminant validity. The results of testing the structural model indicate that control transparency significantly enhances the trust and significantly reduces the risk perception of online banking users. The result also suggested that the outcome feedback significantly enhances the trust of users. We have found that the reduced risk and the increased trust level significantly improve the level of service satisfaction. The increased satisfaction finally leads to the increased loyalty and willingness to pay for the financial services.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.180-192
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• 1993

This study was conducted to investigate bird community and to suggest a proper way how to manage and protect bird community in Sobaeksan National Park. The survey was carried over 3 main trail districts by line transect method to figure out influence factor of inhabitation of wild birds from February to October in 1992. The study results as follows: The observed birds were belong to 9 orders l2 families 58 species, they also have Sparrow Hawk dccipiter nisus, Kestrel Faleo tinnunculus(natural monument no. 323). Scops Owl I'otus scops(natural monument no. :324), Black Woodpecker Dryoaepus martius(natural monument no. 242. R). White-backed Woodpecker Dendroaepos leuotes(R) and Gray-backed Thrush Turdus hortulorum(R). These birds a]so classified into 31 species for residents. 17 species for summer visitor, 6 species for winter visitor. 4 species for passage migrant, respectively. Species richness was 38 species at spry, 33 species at summer. 26 species at autumn and 22 species at winter. The density was 3.00 ea /ha at spring, 2.37 ea /ha at summer, 3.62 ea /ha at autumn and 2.88 ea /ha at winter. Breeding bird community in Sobaeksan National Park was dominated by Hole, Bush-nesting guild and Canopy-foraging guild. Natural vegetation of 900m altitude in 1st section and the grassy plain in 2nd section are to be protected absolutely for the habituation of wild birds. Species richness in 3rd section was higher than any other section owe to a various habitat such as valley. open lands, orchid, farm land and forest etc. Food plants and broad-leaved forest is to be managed for the provision of opulent food resources in autumn and winter, user is to be managed for the successful propagation of wild birds in spring and autumn.

• Fire Science and Engineering
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• v.28 no.3
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• pp.10-19
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• 2014

The fast evacuation from fire floors to evacuation floors in high-rise building fires can minimize the human damage. In this study, an evacuation instrument, which are applicable to the high-rise buildings of adaptable escape mechanisms by the current NFSC 301 (national fire safety code 301), were selected to analyze the applicability in the high-rise buildings over 11th floor through the site adaptability test. The results of the site test were as follows. The elevator type evacuation instrument of new concept developed as a new technology by compensating the defect of evacuation instrument limiting in the high-rise buildings over 11th floor had completed the stability test and the performance certification test in fire stations, which there were no problems in the introduction of the elevator type evacuation instrument as an escape mechanism in the high-rise buildings. The elevator type evacuation instrument using escapers' weight without using electric power was an escape mechanism that many people could evacuate in a short period of time when a fire broke out in the high-rise buildings. In particular, The elevator type evacuation instrument operated by nonpower had the adaptability as a customized escape mechanism considering user characteristics in the buildings for the disabled or patients with an advanced disease.

• Journal of Acupuncture Research
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• v.26 no.6
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• pp.101-110
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• 2009

Objectives : We developed and proposed a guideline for safety and performance assessment of electric cupping apparatus(Class 2 medical device). Methods : We drafted the guideline for safety and performance assessment of electric cupping apparatus by referring the existing standards and guideline, based on online questionnaire for Korean medical doctors and measurement data from commercially available products. Physical dimension of cups and inner vacuum pressure were acquired for the measurement in order to achieve the purposes. Results : This guideline only can be applied to electric cupping apparatus for enhancing blood circulation by employing negative pressure generated by electricity. Seven items of appearance and label, operation test of pump, variation test of input electricity, vacuum level test, vacuum sustain test, cup-size dependent test, noise level test are suggested for evaluation subjects and methods required for electric cupping devices. Requirements for the design and development of electric cupping devices are suggested: vacuum level indicator, vacuum generation rate, pressure control, valve detachment stability, cup comparability, safety measure, surge protection, user friendliness, instruction for use (IFU). Conclusions : We proposed a guideline for safety and performance assessment of electric cupping apparatus to improve the quality of relating products and aid the commercialization of them, by aiming higher industrial competitiveness of the medical device sectors in Korea. Discussion with related institutes such as industry, academy and government is further required. Public hearings also need to be held prior to the establishment of a final guideline and standard.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.97-102
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• 2015

The long line fishing machine is combined with motor and two disc rollers has used on the small size fishing-boat under 1 ton located in near Jeollanam-do seaside. The long line fishing motor is controlled only one direction because the fishing line is loaded heavily at pulling up. On this paper we made the long line fishing 400W power motor controller which it was usually applied under 1 ton fishing boat, and designed the controller using PWM chip, Half bridge driver and MOSFET for one direction motor control. Furthermore some user convenience devices were added like battery indicator and safety protection circuit for battery overdischarge and battery source wire mismatch connection. So we protected the battery from overdicharging when the battery voltage was below 11.5V and fishermen didn't need to worry about source lines misconnection anymore. We confirmed the test version of controller was the good working condition at land and sea.

• Fire Science and Engineering
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• v.31 no.1
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• pp.10-17
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• 2017

Securing fire safety using only fire-fighting facilities is difficult because causes of modern fire vary, such as architectural structures and building use patterns. In order for fire safety to be guaranteed by enacting and revising fire regulations reflecting the fire hazard characteristics and user's characteristics, the introduction of fire influence evaluation (fire risk assessment) system needs to be considered in a timely manner to be adopted but unfortunately two attempts before have failed. In this study, a fire case of urban lifestyle housing was surveyed to introduce a fire influence evaluation system and a field survey on the actual condition of the 414 urban lifestyle housing buildings and fire & evacuation simulation results of one representative building in Suyoung-gu and Nam-gu District of Busan Metropolitan City were analyzed. The necessity, procedures and implementation method of fire influence evaluation system were questioned and tested by the professional fire experts, fire officers and firefighters and architects. On the basis of these facts, introduction of (fire influence evaluation system) should be absolutely adopted and the fire department and fire regulation are eligible to implement the system. Therefore, fire regulation needs to be enacted or revised in accordance with the new fire environment and fire safety system that needs to be built up. Accordingly, aggressive promotion through public hearings on the necessity of fire impact assessments, consensus among departments and fostering experts to carry out fire influence evaluation system will be the core.

• Journal of the Korea Convergence Society
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• v.7 no.4
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• pp.155-162
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• 2016

Communication of art and the expansion of roles are some of the important discourses of art. For a while, many attempts were made to overcome the enjoyment of art by only a few elites and the alienation of roles. In the meanwhile, due to its formative nature, media art has contributed to the various expansion of roles as a familiar art in society and by communicating with the public in various play contents and industrial context. This study will take a step further and examined whether media art can assess and be used in social issues through the characteristic analysis of 'media art information visualization.' The general field of information visualization only focuses on the clarity of information delivery, so it is effective for intuitively identifying various information. However, stiff visual expression must improve user-friendly functions in an era in which users' sensibility is increasing, and it only focuses on the effectiveness of information delivery that its secondary social problem such as personal information protection must be compensated. Thus, this research analyze the characteristics of case works to examine how the visualization of media art information can approach social problems creatively, seek the expansion of the role of art and compensate the areas that general information visualization is missing.

• CRM연구
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• v.1 no.1
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• pp.23-48
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• 2006

Internet B2C marketplace such as 'Auction', 'G Market', 'Daum onket' etc.(called open market) has grown sharply in sales about yearly 100% rate increase in recent 1-2 years in Korea. Although Open marketplace has much reputation and the customer loyalty, almost of merchants participated in open market, which size in sales are medium/small, has poor reputation and trust. Consumers, who have to get in touch with untrustworthy merchants for trade in openmarket, perceive high trade risk which undergo the monetary damages such as 'merchandise never received'. This examines what factors consumer trust develop in online marketplace. This study explores several perceived risk factors in an open market by factor analysis and multi-regression to prove the relationships between the degree of trust for the merchants and the perceived trade risk. 133 data collected from the open market user data in this survey. In this study, the consumer's trade satisfaction in open market is low by 4.2 point degree of 7 point likert scale. and perceives 4 trade risk factors such as (1) 'failure to honor warranty or guarantee' (2) 'defective/poor goods in quality' (3) 'merchandise never received or received late' (4) 'poor information'. the degree of merchant's trust has significant relationship with the degree of perceived risk(sig. = 0.0000, $R^2=.327$) We find that the open market has to enhance the relationship marketing of trust by developing the strategies.