• Journal of Internet Computing and Services
• /
• v.4 no.3
• /
• pp.47-55
• /
• 2003

Multicast protocols ore developed in order to support group communications efficiently, However. there still exist some issues to be solved for deploy multicast protocol in the public internet. This paper refers problem of existing Reliable Multicast Protocols and redesigns component function, and proposes enhanced reliable multicast transport protocol, This paper proposed a improved multicast transport scheme in NACK based reliable multicast. This scheme is much faster than by sender-initiated or receiver-initiated recovery and latency is smaller. Designed components are implemented in UNIX environment using C programming longuage. Then the protocol was evaluated performance through simulation. As the result, proposed protocol is better than existing protocols in both of transmission delay and packet loss. Especially, proposed protocol in this paper con be used in multicast services needed high reliability.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.4
• /
• pp.467-474
• /
• 2010

Stainless steel sheets are widely used as the structural material for railroad cars and commercial vehicles. Structures made of stainless steel sheets are commonly fabricated by gas welding, For the fatigue design of gas welded joints such as fillet joints, it is necessary to obtain design information of the stress distribution at the weldment as well as the fatigue strength of the gas-welded joints. Further, the influence of the geometrical parameters of gas-welded joints on stress distribution and fatigue strength must be evaluated. in this study, ${\Delta}P-N_f$ curves were obtained by fatigue tests. and, the ${\Delta}P-N_f$ curves were rearranged on the basis of the ${\Delta}{\sigma}-N_f$ relation for the hot-spot stresses at the gas-welded joints. These results, were used for conducting an accelerated life test(ALT) From the experiment results, an acceleration model was derived and factors were estimated. The objective is to obtain the information required for the analysis of the fatigue lifetime of fillet welded joints and for data analysis by the statistic reliability method to save time and cost and to develop optimum accelerated life prediction plans.

• Culinary science and hospitality research
• /
• v.15 no.1
• /
• pp.16-29
• /
• 2009

Although the effect of menu quality is very important in customer satisfaction and restaurant management, there are so many problems; many restaurants have not gotten out of their existing frames and ideas of customer services and management. Thus, this study chose some family restaurants, O, T, V, B, M in Seoul and Gwangju and examined the relationships of customer satisfaction, trust and revisit intention identified by their menu quality, using statistical data of total 199 copies of questionnaire. First, menu quality turned out to influence customer satisfaction partially. Second, customer satisfaction turned out to influence revisit intention. Third, trust of a customer turned out to influence revisit intention. In this respect, the image from menu quality of family restaurants perceived by customers must have affected customer satisfaction, trust, and revisit intention positively. Thus, it is expected that the study can contribute to working out effective business strategies in family restaurants in future.

• Journal of Digital Convergence
• /
• v.10 no.9
• /
• pp.137-149
• /
• 2012

It has become a crucial issue for IT service firms how to form positive relationships with their customers in order to retain existing customers and potential customers. To address this issue, many researchers have introduced the concept of consumer relationship proneness(CRP). This present study examines if CRP is related to trust and commitment that enhance the intention to reuse. Using PLS, we analyzed 200 data collected through a survey of global electronic company members experienced IT outsourcing services. As a result, CRP has a defined impact on both trust and commitment, and relationships between trust and commitment, commitment and reuse intention have a positive effect. On the other hand, trust does not affect reuse intention. Based on these results, it presents a discussion for future research and the implications for CRP.

• Composites Research
• /
• v.26 no.1
• /
• pp.29-35
• /
• 2013

Composite sandwich structure can improve the specific bending stiffness significantly and save the weight nearly 30 percent compared with the composite laminates. However, it has more inherent uncertainties of the material property caused by manufacturing process than metals. Therefore, the reliability-based probabilistic design approach is required. In this paper, the PMS(Probabilistic Margin of Safety) is calculated for the simplified fuselage structure made of composite sandwich to provide the probabilistic reasonable evidence that the classical design method based on the safety factor cannot ensure the structural safety. In this phase, the probability density function estimated by CMCS(Crude Monte-Carlo Simulation) is used. Furthermore, the RBDO(Reliability-Based Design Optimization) under the probabilistic constraint are performed, and the RBDO-MPDF(RBDO by Moving Probability Density Function) is proposed for an efficient computation. The examined results in this paper can be helpful for advanced design techniques to ensure the reliability of structures under the uncertainty and computationally inexpensive RBDO methods.

• Agrochemical news magazine
• /
• v.22 no.5 s.168
• /
• pp.2-4
• /
• 2001

• Journal of Digital Convergence
• /
• v.10 no.8
• /
• pp.81-90
• /
• 2012

This study is to establish the effects on B2B(Business-to-Business) industrial product market of the Marketing Communication which used in B2C(Business-to-Customer) has influences on Trust and Trust has influences on Long-Term Orientation through survey targeting 177 wholesale and retail dealers of Air-Tool distribution. Accordance with these conclusions, The Trust that the customer felt for Supplier was a positive influence on Long-Term Orientation. Also advertising of marketing communication is useful for increasing the Trust. Thus, to increase Long-Term Orientation on B2B, supplier needs to increase Trust and to find another marketing communication factors increased Trust is needed.

• Management & Information Systems Review
• /
• v.32 no.5
• /
• pp.193-231
• /
• 2013

As developed IT, Word-of-Mouth(WOM) used varied terms as buzz marketing and viral marketing, and impressed that importance. Despite introduced new marketing tool on managers and professionals, online word-of-mouth including SNS lack of study on social network what based viral in marketing. In social network, patterns of relationship between individuals influence each other individual behaviors. Therefore this research grouped friendship-network and advice-network by characteristics, studied on trust of information source that antecedents of word-of-mouth in network. This study examined that affect- and cognition based trust affect WOM acceptance as WOM behaviors and examined effect of type of product as moderating variable. Additional this literature studied that WOM acceptance affect WOM recommend. To find the Influence of Trust on Word-of-Mouth Behaviors, a survey has done 206 samples(undergraduate students). The results of this study are as following : First, type of trust different friendship network and advice network. Affect-based trust is outstanding in friendship network than in advice network, while cognition-based trust stands out in advice network than another. Second, affect- and cognition based trust positive affect WOM acceptance. Contrary to expectations, what is preconceived trust in network have a similar effect for WOM acceptance regardless of type of trust. Third, WOM acceptance positive affect WOM recommend. Fourth, affect based trust affect WOM acceptance of hedonic product rather than utilitarian product. Upon especially in friendship network terms, affect-based trust has a more effect on WOM acceptance than cognition-based trust. This study has many implications. First, it is important that trust what have an influence WOM acceptance grouped affect- and cognition based trust. Second, it confirmed that trust is antecedents of positive WOM. Third, it is important that network grouped friendship network and advice-network by trust. Fourth, it gave managerial implications that they have to supply WOM through which network by type of product. We This study classified network and trust based on previous study. Then it examined relations between WOM behaviors. Further research could do enrich various things for example various age group, valence of message, quality of information.

• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06d
• /
• pp.181-183
• /
• 2012

WBAN(Wireless body area network)에서 사용되는 저 출력 센서 디바이스는 상당한 패킷 손실률을 발생시키며 데이터의 신뢰성을 떨어뜨리는 원인이 된다. 기존의 IEEE 802.15.4 MAC 프로토콜은 데이터 오류 발생 시 수신한 전체 데이터를 재전송하기 때문에 불필요한 에너지 소모와 오버헤드가 발생된다. 특히 WBAN 환경에서 인체 내부에 이식되는 디바이스의 경우 배터리 교체의 어려움과 초 저전력을 요구하기 때문에 노드의 수명 유지를 위해 사용되는 전력 소모량도 중대한 문제가 되고 있으며, 전체 데이터를 재전송하는 기존의 방식에서 발생하는 에너지 소모는 노드의 수명을 단축시키는 원인이 된다. 본 논문에서는 저전력과 신뢰성을 요구하는 WBAN 환경에서 수신 오류율 변화에 따른 데이터 동적 블록화 기법을 사용하여 재전송 데이터의 크기를 줄인다.

• Korean Journal of Materials Research
• /
• v.10 no.3
• /
• pp.184-190
• /
• 2000

We investigated the effect of filler content on the thermo-mechanical properties of modified ACA composite materials by incorporation of non-conducting fillers and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACA s composites with different content of non-conducting fillers, differential scanning calorimeter (DSC), and thermo-gravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), and thermo-mechnical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in the content of filler brought about the increase of Tg^{DSC}$ and $Tg^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significantly affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.