• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권3호
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• pp.341-357
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• 2010

Forward Error Correction (FEC) techniques have been adopted to overcome packet losses and to improve the quality of video delivery. The efficiency of the FEC has been significantly compromised, however, due to the characteristics of the wireless channel such as burst packet loss, channel fluctuation and lack of Quality of Service (QoS) support. We propose herein an Adaptive Cross-layer FEC mechanism (ACFEC) to enhance the quality of video streaming over 802.11 WLANs. Under the conventional approaches, FEC functions are implemented on the application layer, and required feedback information to calculate redundancy rates. Our proposed ACFEC mechanism, however, leverages the functionalities of different network layers. The Automatic Repeat reQuest (ARQ) function on the Media Access Control (MAC) layer can detect packet losses. Through cooperation with the User Datagram Protocol (UDP), the redundancy rates are adaptively controlled based on the packet loss information. The experiment results demonstrate that the ACFEC mechanism is able to adaptively adjust and control the redundancy rates and, thereby, to overcome both of temporary and persistent channel fluctuations. Consequently, the proposed mechanism, under various network conditions, performs better in recovery than the conventional methods, while generating a much less volume of redundant traffic.

• Journal of Nutrition and Health
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• 제31권9호
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• pp.1498-1507
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• 1998

The purposes of this study were to : a) examine the current foodservice management practices of twenty-one seniors centers in charge of hoke-delivered meal programs, b) evaluate the attitudes of one hundred and ten recipients of meal service program, and c) provide feedback for the efficient and effective foodservice management for the elderly. Statistical data analysis was completed using the SAS package program for descriptive analysis, T-test, and ANOVA. The results of quantitative analysis indicated that the costs of meals, containers and special foods were mostly dependent on the support from local government(Seoul city). The centers where the volunteers were over seventy five p ercent of the workers were frtty-eight percent and sixty-seven percent of the subjects in food preparation and food delivery to the homebound clients, respectively. Meal preparation and food purchasing were mainly practiced by social welfare worker. Standardized recipes were not developed and meal preparation was controlled under the cook' and volunteers' experiences. The survey results of recipients who participated the home-delivered meals program showed that the mean of meal satisfaction score was rated over three point five in the five-point scale. There were significant differences between dependent variables(volunteer's kindness, plate waste, menu variety) and independent variables(sex, receiving periods and family type of the subjects). (Korean J Nutrition 31(9) : 1498-1507, 1998)

• 한국정보과학회논문지:정보통신
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• 제28권4호
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• pp.578-585
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• 2001

IP 멀티캐스트는 Best-Effort 서비스를 제공하므로 신뢰적인 전송을 보장하지 않는다. 최근 신뢰적인 전송을 보장하기 위한 다양한 접근이 시도되고 있지만, 인터넷상에서 확장성 있는 신뢰적인 멀티캐스트 전송을 구현하기엔 아직까지 미흡하다. 본 논문에서는 이를 극복하기 위해 확장성과 신뢰성을 지원하는 신뢰적인 멀티캐스트 구조 (RMA)를 제안한다. 제안하는 모델은 수신자 기반의 재전송 요청을 통해 신뢰성을 보장하는 한편, 멀티캐스트 라우터 가 피드백을 억제함으로써 확장성을 보장한다. 또한, 기존의 멀티캐스트 라우팅 정보를 최대한 활용하여 프로토콜 변경비용 및 오버헤드를 최소화한다. 성능분석 결과, 제안하는 모델은 확장성과 호환성 측면에서 기존의 연구보다 우수성을 보였다.

• 유통과학연구
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• 제17권11호
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• pp.27-34
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• 2019

Purpose: This study explored the improvement and the direction of the smart disaster management system newly attempted in South Korea by analyzing the utilization of the existing system. This study focuses on making it easy to apply to user tasks and improving on site information. Research design, data and methodology: Problems were identified through field surveys with administrators in charge of administration and public institutions based on GIS based status board for NDMS which is widely used in Korea. Also, this study attempted to generalize to specialists in disaster management who are more likely to use the system in the future. Results: We derived improvement plans and verified the results through expert feedback. The results show that the GIS based status board for NDMS is cumbersome to use due to the vast array of unnecessary information compared to the high expected utilization. Conclusions: We found that improving the speed and accuracy of the smart disaster management information delivery system is necessary. Also, it is important to identify reasons for not improve the willingness to use this technology in disaster management and to figure out the process by which field personnel makes decisions that smart disaster information cannot be used for disaster management.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권4호
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• pp.524-533
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• 2017

This paper presents a novel reset scheme for mm-scale sensing systems with stringent volume and area constraints. In such systems, multi-layer structure is required to maximize the silicon area per volume and minimize the system size. The multi-layer structure requires wirebonding connections for power delivery and communication among layers, but the area overhead for wirebonding pads can be significant. The proposed reset scheme exploits already existing power wires and thus does not require additional wires for system-wide reset operation. To implement the proposed reset scheme, a power management unit is designed to impose reset condition, and a reset detector is designed to interpret the reset condition indicated by the power wires. The reset detector uses a coupling capacitor for the initial power-up and a feedback path to hold the developed supply voltage. The prototype reset detector is fabricated in a $180-{\mu}m$ CMOS process, and the measurement results with the prototype mm-scale system confirmed robust reset operation over a wide range of temperatures and voltages.

• 한국조리학회지
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• 제9권2호
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• pp.44-63
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• 2003

This study is about internet marketing of family restaurant through marketing mix and we found out the way which can make to activate by means of analysis of family restaurant's homepage. This study was done as following precedure. First, we've compared between characteristic was based on contents distinctive quality of family restaurant's homepage through the marketing mix. And in the next step, we've compared and ana lysed homepage of family restaurant which was chosed by the internet surfing. In the last, we evaluate strategy of marketing mix which is going well in the each field of business and then research of the way can improve internet-marketing. We draw the findings which is seperated by goods, price, promotion, distribution, other service according to marketing constituents. As a result of study, it is found that each company has given much more weight on some part in internet marketing's field of activity. In general, they put an emphasis on activity of goods and promotion. On the other hands they don't consider prices and delivery to be important compared with other parts. One of the most important things about internet-marketing is that fast and exact feedback and community makes each firm to be able to help to communicate with customer. It's like off-line-restaurant make use of free-coupon and an anniversary service.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권3호
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• pp.886-905
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• 2012

Set-top Box (STB) has evolved from being a device just sitting on top of a TV shelf to a device providing a gateway to the Internet for a home network, receiving services from multiple content providers, and enabling and ensuring Quality of Service (QoS) for the streaming media. IP Multimedia Subsystem (IMS), with its promise to provide a converged access network for multimedia service delivery (such as Triple play & Quadruple play services), has to guarantee QoS support. To enable QoS in IMS-based networks, we have designed a set-top box which provides feedback to the service provider to ensure end-to-end QoS. Our set-top box is designed to provide virtual platforms such that it can support multiple service providers. Each service provider is able to manage its own multimedia streams and ensures the desired network performance for each flow. The set-top box also works as a Home Gateway and provides end-to-end QoS support to the client nodes.

• 대한영양사협회학술지
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• 제8권3호
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• pp.318-327
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• 2002

The purposes of this study were to: a) examine charateristics of foodservice manaegment practices; b) investigate characteristics of recipients; c) analyze foodservice systems; and d) provide feedback for the efficient and effective foodservice management of welfare institutions for the homeless in Korea. A total of 27 sites was analyzed by questionnaire survey. Satatistical data analysis was completed using the SPSS package program for descriptive analysis. As results of site recipients' characteristics, 69% of total sites were males and 31% were female recipients. Average 60% of recipients were from 30 to 50 years old. Major diseases of recipients were high pressure, and obesity. According to the result of foodservice system analysis, the average meal cost per day was about 2,943 won and average food cost percentage was 29%. Average number of meals per day was about 600 meals. Mostl sites had one dietitian and 48.1% of sites had one cook as a full-time employee. In the part of procurement, dietitians were major chargers of sites for purchasing foods. Major purchasing method was the order and delivery contract. About a half of sites used cycle menu system and standardized recipies. Most of sites had recipients' survey systems for evaluating meal satisfaction. Dietitians at sites had problems on lack of cooking professionals and low meal cost budget for providing higher quality of foods to cure recipients. The results suggested that financial and systematical supports by the government would be very necessary to meet the goal of nutritional balanced meal services.

• Journal of Information Processing Systems
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• 제17권5호
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• pp.972-988
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• 2021

At present, DevOps environments are getting popular in software organizations due to better collaboration and software productivity over traditional software process models. Software artefacts in DevOps environments are vulnerable to frequent changes at any phase of the software development life cycle that create a continuous integration continuous delivery pipeline. Therefore, software artefact traceability management is challenging in DevOps environments due to the continual artefact changes; often it makes the artefacts to be inconsistent. The existing software traceability related research shows limitations such as being limited to few types of artefacts, lack of automation and inability to cope with continuous integrations. This paper attempts to overcome those challenges by providing traceability support for heterogeneous artefacts in DevOps environments using a prototype named SAT-Analyser. The novel contribution of this work is the proposed traceability process model consists of artefact change detection, change impact analysis, and change propagation. Moreover, this tool provides multi-user accessibility and is integrated with a prominent DevOps tool stack to enable collaborations. The case study analysis has shown high accuracy in SAT-Analyser generated results and have obtained positive feedback from industry DevOps practitioners for its efficacy.

• 유통과학연구
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• 제20권7호
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• pp.57-64
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• 2022

Purpose: The government of India has initiated the Covid-19 Vaccination drive from early January 2021. Vaccination is identified to be best option to protect the people across the globe. However, owing to fast wide spread of the Covid-19, the Vaccine Distribution is a major challenge owing various issues like temperature control, infrastructure, hesitancy, geographical diversity, and other critical factors. Various research is carried out globally to understand and study the Vaccine Distribution issues based on the respective country issues and factors. Research Design, Data, and Methodology: This research paper attempts to explore prominent factors that could be taken up on priority for better and effective vaccination program. The study tries to rank various factors and sub-factors affecting vaccine distribution in India. AHP methodology based on feedback from 22 experts from the Vaccine industry has been deployed to get the desired results. Result: The results show that factors vaccine approval process, geographical prioritization, power supply, infrastructure maintenance costs for vaccine storage, and vaccine pricing are the prominent factors of effective vaccination in the country. Conclusion: The role and need for district-level health officers towards vaccine storage has been brought forward. A long-term effective vaccination policy is needed for optimum vaccine distribution.