• 한국통신학회논문지
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• 제30권9A호
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• pp.762-771
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• 2005

In this paper, an efficient Adaptive quality-of-service (QoS) traffic control scheme with priority scheduling is proposed for the multimedia traffic transmission over wireless access networks. The objective of the proposed adaptive QoS control (AQC) scheme is to realize end-to-end QoS, to be scalable without the excess signaling process, and to adapt dynamically to the network traffic state according to traffic flow characteristics. Here, the reservation scheme can be used over the wireless access network in order to get the per-flow guarantees necessary for implementation of some kinds of multimedia applications. The AQC model is based on both differentiated service model with different lier hop behaviors and priority scheduling one. It consists of several various routers, access points, and bandwidth broker and adopts the IEEE 802.1 le wireless radio technique for wireless access interface. The AQC scheme includes queue management and packet scheduler to transmit class-based packets with different per hop behaviors (PHBs). Simulation results demonstrate effectiveness of the proposed AQC scheme.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.1193-1196
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• 2005

In this paper, we presents a new multimedia service transmit method using IPv6. The IPv6 provides the address system of 128 bit and the address space which is infinite it provides. But it will not become the IPv4 and interchange not to be, it uses the DSTM Transition mechanism which will reach and the IPv4 center in the packet header the service type it will be able to support the service class of multi type (TOS) it secures the weak point of data transfer delay it puts a base in the IPv6. The efficiency of this proposed technique have been proven by MPEG-4 streaming video streaming of the IPv6 namely, 6Xtream embodied a order form/live streaming server and the client which it uses to be possible in base and real-time decoding method.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제19권4호
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• pp.229-245
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• 2015

In this study, I investigated how pre-service teachers (PSTs) proved three geometric problems by using Geometer's SketchPad (GSP) software. Based on observations in class and results from a test of geometric reasoning, eight PSTs were sorted into four of the five van Hiele levels of geometric reasoning, which were then used to predict the PSTs' levels of reasoning on three tasks involving proofs using GSP. Findings suggested that the ways the PSTs justified their geometric reasoning across the three questions demonstrated their different uses of GSP depending on their van Hiele levels. These findings also led to the insight that the notion of "proof" had somewhat different meanings for students at different van Hiele levels of thought. Implications for the effective integration of technology into pre-service teacher education programs are discussed.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2005년도 하계학술대회
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• pp.338-341
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• 2005

Recently there are increasing needs for Internet and various kinds of contents. These traffics for various contents need more amount of data to provide high-quality information and require various QoS depending on the characteristics of contents. However, current Internet service supports BE (Best Effort) service only, therefore IntServ (Integrated Service) scheme and DiffSserv (Differentiated Service) scheme are represented to support QoS in IP layer. This paper describes new scheme that provides QoS taking into account the traffic characteristics over Mobile IPv6 network based on IEEE 802.11e by decreasing signal process time using traffic class of DiffServ and evaluates the performance through computer simulation.

• 정보통신설비학회논문지
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• 제7권1호
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• pp.33-39
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• 2007

Recently there are increasing needs for Internet and various kinds of contents. These traffics for various contents need more amount of data to provide high-quality information and require various QoS depending on the characteristics of contents. However, current Internet service supports BE (Best Effort) service only, therefore IntServ (Integrated Service) scheme and DiffServ (Differentiated Service) scheme are represented to support QoS in IP layer. This paper describes new scheme that provides QoS taking into account the traffic characteristics over Mobile IPv6 network based on IEEE 802.11e by decreasing signal process time using traffic class of DiffServ and MAC and evaluates the performance through computer simulation.

• 수산해양교육연구
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• 제17권3호
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• pp.305-323
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• 2005

To reveal secondary teachers' in-service education needs, in-depth interviews were conducted with 15 individual teachers based on semi-structured questions and qualitative data analysis procedures were adopted. They wanted to have; a. more knowledge of one's subject, subject related information, culture and common sense, counseling psychology, foreign language, and the 7th curriculum, b. better skills of student-centered teaching-learning methods, guidance and class management, good use of computers, and educational evaluation, c. improved attitudes regarding democratic problem solution processes, conversation with and service to students from their viewpoints, commitment to preparations for teaching, educational innovation and improvement, elimination of improperness, and pride of teaching job.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.471-474
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• 2016

본 논문은 각 국가에서 생산되는 농축산물에 관련되어 국제적으로 제공받을 수 있는 연관 서비스 리스트를 찾아주는 표준을 제안함으로써, 농축산물의 클래스 수준 식별자를 이용하여 연관된 서비스 리스트를 보유하고 있는 네임서버를 찾고 저장되어 있는 서비스 리스트를 사용자에게 제공하는 것을 목적으로 한다.

• 한국유통학회지:유통연구
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• 제2권1호
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• pp.59-85
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• 1997

The automobile industry in Korea has grown to the fifth in the world in terms of production capacity. In spite of the production growth, the marketing aspects such as distribution and customer service in the auto industry are still behind the world-class. Thus, the major purposes of this paper are as follows. The first is to analyze competitive structure of the industry and to compare distribution strategies of the major auto firms(Hyundai, Daewoo, and Kia). The second is to theoretically explain the transition from the vertical marketing system to the dealer system using transaction cost analysis. The third is to compare auto distribution channels in Korea with those in the U.S. and Japan. Finally, an optimal channel stucture in the auto industry is suggested after reviewing five alternative channel structures such as corporate-owned VMS, sales-specializing firm, multiplex system(VMS+limited dealer system), dual sales channel, and advanced dealer system. In the short-run, sales-specilizing firm was suggested as an optimal channel system to enhance customer satisfaction by integrating sales and customer service. In the long-run, advanced dealer system through regional differentiation was desirable for an optimal channel structure by organically integrating new car sales, used car sales, and after service to provide total marketing service to customers.

• Restorative Dentistry and Endodontics
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• 제47권1호
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• pp.5.1-5.11
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• 2022

Objectives: This study aimed to assess the clinical longevity of a bulk-fill resin composite in Class II restorations for 3-year. Materials and Methods: Patient record files acquired from the 40 patients who were treated due to needed 2 similar sizes Class II composite restorations were used for this retrospective study. In the experimental cavity, the flowable resin composite SDR was inserted in the dentinal part as a 4 mm intermediate layer. A 2 mm coverage layer with a nano-hybrid resin composite (CeramX) was placed on SDR. The control restoration was performed by an incremental technique of 2 mm using the nano-hybrid resin composite. The restorations were blindly assessed by 2 calibrated examiners using modified United States Public Health Service criteria at baseline and 1, 2, and 3 years. The data were analyzed using non-parametric tests (p = 0.05). Results: Eighty Class II restorations were evaluated. After 3-years, 4 restorations (5%) failed, 1 SDR + CeramX, and 3 CeramX restorations. The annual failure rate (AFR) of the restorations was 1.7%. The SDR + CeramX group revealed an AFR of 0.8%, and the CeramX group an AFR of 2.5% (p > 0.05). Regarding anatomical form and marginal adaptation, significant alterations were observed in the CeramX group after 3-years (p < 0.05). The changes in the color match were observed in each group over time (p < 0.05). Conclusions: The use of SDR demonstrated good clinical durability in deep Class II resin composite restorations.

• 한국컴퓨터정보학회논문지
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• 제24권4호
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• pp.113-121
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• 2019

The purpose of the study is to identify the influence of learning participation on learning outcomes in programming courses. Based on the literature review, learning participation is composed of three sub components: participation in preview, class, and review. Learning outcomes are categorized by academic achievement, learning satisfaction, and learning motivation. A survey was conducted with 267 students enrolled in programming courses from three IT departments at Myongji College. Findings revealed that participation in review and participation in class predicted all sub components of learning outcomes. Participation in review was found to have a greater effect on learners' achievement and participation in class was found to have a greater impact on learning satisfaction and motivation. However, the results showed that participation in class was not an influential factor for learning outcomes. Implications for enhancing learning participation and suggestions for future research are also discussed.