• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권12호
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• pp.5150-5169
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• 2015

Mobile Ad hoc NETworks (MANETs) are the best choice when mobility, scalability, and decentralized network infrastructure are needed. Because of critical mission applications of MANETs, network security is the vital requirement. Most routing protocols in MANETs assume that every node in the network is trustworthy. However, due to the open medium, the wide distribution, and the lack of nodes' physical protection, attackers can easily compromise MANETs by inserting misbehaving nodes into the network that make blackhole attacks. Previous research to detect the misbehaving nodes in MANETs used the overhearing methods, or additional ACKnowledgement (ACK) packets to confirm the reception of data packets. In this paper a special lightweight acknowledgement-based method is developed that, contrary to existing methods, it uses ACK packets of MAC layer instead of adding new ACK packets to the network layer for confirmations. In fact, this novel method, named PIGACK, uses ACK packets of MAC 802.11 to piggyback confirmations from a receiver to a sender in the same transmission duration that the sender sends a data packet to the receiver. Analytical and simulation results show that the proposed method considerably decreases the network overhead and increases the packet delivery ratio compared to the well-known method (2ACK).

• 한국병원경영학회지
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• 제16권4호
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• pp.67-84
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• 2011

The open Hospital Attending Physician System has been discussed and operated for developing the efficiency and the substitutes for an increase in medical expenses, for overlapping investment in medical resources, and for normalization of medical delivery system. This study assessed the related factors to the acceptance and introduction of Attending Physicians on ophthalmologist. Data was collected mail response to 179 ophthalmologists in 2005. Applying multilevel logistic regression, we examined the relationship between their acknowledgment, attitude and acceptance of the open Hospital Attending Physicians System. The percentage of participation in Hospital Attending was indicated to be 3.9%. The 44.7% of all participants agreed to adopting the Hospital Attending, 33.5% of doctors are willing to participate in the future. The positive and normal attitude of physician toward the Hospital Attending is 6.6 times (95%CI 1.315, 33.138) and 55.2 times(95%CI 11.352, 268.347) more than that of negative after adjustment for other variables. Attitude was found to be the important factor influencing physicians' participation in the Attending Hospital. Thus, it is need to development and implication for the strategies that lead the practical necessity and positive attitude toward the Attending Hospital.

• Journal of Communications and Networks
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• 제13권1호
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• pp.43-49
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• 2011

In this paper, a new medium access control (MAC) protocol entitled three-phase multiple access with continual contention resolution (TPMA-CCR) is proposed for wireless multi-hop ad hoc networks. This work is motivated by the previously known three-phase multiple access (TPMA) scheme of Hou and Tsai [2] which is the suitable MAC protocol for clustering multi-hop ad hoc networks owing to its beneficial attributes such as easy collision detectible, anonymous acknowledgment (ACK), and simple signaling format for the broadcast-natured networks. The new TPMA-CCR is designed to let all contending nodes participate in contentions for a medium access more aggressively than the original TPMA and with continual resolving procedures as well. Through the systematical performance analysis of the suggested protocol, it is also shown that the maximum throughput of the new protocol is not only superior to the original TPMA, but also improves on the conventional slotted carrier sense multiple access (CSMA) under certain circumstances. Thus, in terms of performance, TPMA-CCR can provide an attractive alternative to other contention-based MAC protocols for multi-hop ad hoc networks.

• 수산해양교육연구
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• 제27권3호
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• pp.614-624
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• 2015

Traditionally, fathers have been a bread earner and responsible for external matters as the head of household. However, the interest of today's fathers in their children has changed from that of the traditional fathers due to the increased employment of female, decreased birth rate and the trend of shared role in parenting. The purpose of this study was to identify the perception type of fathers of preschool children regarding obesity and the characteristics of the type by applying Q-methodology, and to create the basic data for the development of education programs for fathers or policy-making to prevent child obesity. Data were collected by applying 38 Q statements to 24 fathers of preschool children. Collected data were analyzed with the PC QUANL program. Results indicate that fathers' perception of obesity was divided into three types: 'management of physical activity and diet,' 'generous acknowledgment of reality' and 'compromised emphasis on homemade meal.' The 'compromised emphasis on homemade meal' type is those who consider homemade food important, although they sometimes suggest conditions to make their children cooperative for food. It was found that the subject of the study uniformly recognized that processed foods, fast foods or chocolates are harmful to health. The type of fathers' perception of obesity in preschool children was discussed, focusing on the perception type identified in this study.

• 한국의류학회지
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• 제21권3호
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• pp.487-501
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• 1997

Prepurchase decision making process was investigated for the female high school students grouped by fashion leadership. Differences in the fashion leadership were also investigated among the groups determined by demographic characteristics. Data were obtained from 600 female students attending at 4 different high schools in Seoul by self-administered questionnaires, and 430 were used for the data analysis. Respondents were divided into 5 groups by fashion leadership: innovators(6.3%), early adopters(29.8%) , early majority(43.7%) , late majority(16.9%) , laggards(3.3%) , The groups with higher monthly allowances and monthly clothing expenditures showed higher fashion leadership. At the problem recognition stage, students with higher fashion leadership felt buying needs more often than those with lower fashion leadership. At the information search stage, students with higher fashion leadership tended to use higher number of information sources and mass media, visited stores more often, spent more time and collected new information more often, and tended to show higher satisfaction levels with searched information than students with lower fashion leadership. Leaders tended to search information at bonded goods stores and small shops in the area, and laggards prefered to visit small stores in the market. At the alternative evaluation stage, students with higher fashion leadership reported to use higher number of evaluative criteria and consider brand name, acknowledgment of others, becomingness with wardrobe as important criteria for evaluating apparel products; those with lower fashion leadership thought utility, comfort, size, sewing quality an6 fit as key criteria.

• 한국컴퓨터정보학회논문지
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• 제6권3호
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• pp.50-55
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• 2001

비 신뢰성 네트워크에서 실시간 비디오 전송을 위한 에러 복원 (Error Resilience)기법들을 살펴보고자 한다. 소스 코딩 단계에서 에러 제어를 위해서 각 디코더는 에러검출(Error Detection). 재동기화 (Resynchronization) 그리고 에러감춤 (Error Concealment)을 할 수 있어야 한다. 더군다나 소스 코더를 채널환경에 맞추기 위한 코딩제어(Coding Control)를 통해서 반송정보에 대한 적절한 처리 기법을 논하였다. 우리는 채널환경에 맞춘 소스코딩을 목적으로 한 에러 추적 (Error Tracking), 에러 국한 (Error Confinement) 그리고 참조그림선택 (Reference Picture Selection) 기법을 검토하고 비교하고자 한다. 그리고 피드백 기반 소스코딩이 미디언 서버에 저장되어 있는 이전에 압축된 비디오와 어떻게 관련되어 있는지 살펴보고자 한다.

• 산경연구논집
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• 제12권12호
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• pp.25-33
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• 2021

Purpose: This paper estimates the impact of the epidemic crisis on election outcomes through investigating the effect of Covid19 crisis on election results of 21st General Election held in April 15th 2020 in Korea. Research design, data and methodology: This study employs Ordinary Least Square (OLS) method using district-level data from Seoul and Gyeonggi province available at National election data in Korea. Results: Despite the current crisis in Korea, Covid-19 has had positive effects on voter turnout on average, after controlling for other factors. On the other hand, the effect of Covid-19 on the voter turnout was negative in districts with a larger aging population and higher health insurance premiums. In addition, Covid-19 negatively impacted vote shares for the incumbent party, while its rival party saw gains in their votes. Conclusion: The effect of Covid-19 election outcomes in Korea is distinct from other countries due to the nationwide acknowledgment of the Korean government's achievement in managing the epidemic. This implies that the crisis management ability of a government is crucial in gaining support for an incumbent party in future elections. Countries facing upcoming elections need to implement acceptable Covid-19 restriction policies as well as economic support for compensation to reap similar benefits.

• 동아시아경상학회지
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• 제9권4호
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• pp.81-92
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• 2021

Purpose - Work stress environment is expanding alongside the speed of worldwide change and psychological well-being concerns are coming about because pressure over-burden can bring about lost workdays, lower representative usefulness, and high occupation turnover rates. For this reason, this study investigates to provide how practitioners can manage employee work stress using health psychology based on prior studies. Research design, Data, and methodology - Qualitative textual research involves collecting and analyzing various non-numeric data to establish different concepts or opinions in prior literature. That means that the present researcher carried out qualitative research in multiple ways, investigating many kinds of previous textual data, such as prior published peer-reviewed resources and case studies analysis. Result - The results revealed that directed symbolism has been displayed to improve prosperity and tranquility among employees with an assortment of persistent infections. Like diaphragmatic breathing, reflection practices consolidate zeroing in on a particular article or sensation (like breathing) while at the same time separating from other distracters and controlling inward encounters (for example, feelings, musings) through non-critical acknowledgment. Conclusion - This research proposes that intellectual rebuilding or figuring out how to perceive maladaptive musings and change them to reflect more versatile; judicious idea examples can fundamentally further develop temperament, diminish pressure, and reduction negative feelings for employees.

• Structural Monitoring and Maintenance
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• 제6권2호
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• pp.161-171
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• 2019

There have been a few checking frameworks intended to ensure and improve the nature of their regular habitat. The greater part of these frameworks are constrained in their capacities. In this paper, the insightful checking framework intended for debacle help and administrations has been exhibited. The ideal administrations, necessities and coming about plan proposition have been indicated. This has prompted a framework that depends fundamentally on ecological examination so as to offer consideration and security administrations to give the self-governance of indigenous habitats. In this sense, ecological acknowledgment is considered, where, in light of past work, novel commitments have been made to help include based and PC vision situations. This epic PC vision procedure utilized as notice framework for avalanche identification depends on changes in the normal landscape. The multi-criteria basic leadership strategy is used to incorporate slope data and the level of variety of the highlights. The reproduction consequences of highlight point discovery are shown in highlight guide coordinating toward discover steady and coordinating component focuses and effectively identified utilizing these two systems, by examining the variety in the distinguished highlights and the element coordinating.

• International Journal of Computer Science & Network Security
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• 제22권6호
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• pp.319-331
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• 2022

The latest global COVID-19 pandemic has made the use of facial masks an important aspect of our lives. People are advised to cover their faces in public spaces to discourage illness from spreading. Using these face masks posed a significant concern about the exactness of the face identification method used to search and unlock telephones at the school/office. Many companies have already built the requisite data in-house to incorporate such a scheme, using face recognition as an authentication. Unfortunately, veiled faces hinder the detection and acknowledgment of these facial identity schemes and seek to invalidate the internal data collection. Biometric systems that use the face as authentication cause problems with detection or recognition (face or persons). In this research, a novel model has been developed to detect and recognize faces and persons for authentication using scale invariant features (SIFT) for the whole segmented face with an efficient local binary texture features (DLBP) in region of eyes in the masked face. The Fuzzy C means is utilized to segment the image. These mixed features are trained significantly in a convolution neural network (CNN) model. The main advantage of this model is that can detect and recognizing faces by assigning weights to the selected features aimed to grant or provoke permissions with high accuracy.