• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.1190-1193
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• 2009

최근 무선네트워크의 급격한 발달로 이동 중에도 통신을 할 수 있는 요구사항에 IETF에서는 Mobile IPv6(MIPv6)라는 기술을 제안하였다. MIPv6는 IPv6환경에서 모바일 노드(모바일 노드)가 이동을 하면서도 통신을 할 수 있는 기술인데, 실제 상용망에서는 사용되지 않고 있다. 그 이유는 모바일 노드에 이동성을 제공하는 모바일 스택의 탑재가 높은 오버헤드를 가지고 있고, 시그널링 비용이 많이 들기때문이다. 이와 같은 문제를 해결하기 위해서 지난 해 Proxy Mobile IPv6(PMIPv6)가 표준화 되었다. PMIPv6는 모바일 노드에 이동성을 제공하는 모바일 스택을 올리지 않고 네트워크 엔티티가 대신 모바일 스택을 가지고 시그널링을 처리하기 때문에 결과적으로 시그널링 비용을 줄였다. 하지만 PMIPv6에서는 인접한 네트워크 사이에서 패킷을 전송할 때 MAG간의 통신이 가능하지 않고, 오직 LMA를 통하여 대응 노드(대응 노드)에게 패킷을 전송할 수 있다. 게다가 같은 서브넷에 있는 대응 노드에게 패킷을 전송할 때도 LMA를 거치게 되는 불필요한 과정이 발생한다. 게다가 LMA를 통하여 패킷을 전송하는 방식은 지연과 리오더링(Re-Ordering)을 발생시켜본 패킷 재전송을 유발하여 전송 품질을 떨어뜨리게 된다. 본 논문에서는 인접한 MAG간의 통신, 또는 같은 서브넷 내에서의 통신에서 LMA를 거치지 않고 통신을 할 수 있는 방안으로 블룸 필터를 이용한 통신 기법을 제안한다.

• Journal of Educational Research in Mathematics
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• v.16 no.1
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• pp.1-23
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• 2006

It is regarded as critical to analyse and re-appreciate Euclidean geometry for the sake of improving school geometry This study, a critical analysis of demonstrative plane geometry in current secondary school mathematics with an eye to the viewpoints of 'Elements of Geometry', is conducted with this purpose in mind. Firstly, the 'Elements' is analysed in terms of its educational purpose, concrete contents and approaching method, with a review of the history of its teaching. Secondly, the 'Elemens de Geometrie' by Clairaut and the 'histo-genetic approach' in teaching geometry, mainly the one proposed by Branford, are analysed. Thirdly, the basic assumption, contents and structure of the current textbooks taught in secondary schools are analysed according to the hypothetical construction, ordering and grouping of theorems, presentations of proofs, statements of definitions and exercises. The change of the development of contents over time is also reviewed, with a focus on the proportional relations of geometric figures. Lastly, tile complementary way of integrating the two 'Elements' is explored.

• Journal of Distribution Science
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• v.14 no.10
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• pp.153-164
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• 2016

Purpose - In general, large companies have larger organizations, funds, and systems to provide more effective and efficient services in the market. However, development needs to support the livelihood of ordinary citizens who work for small businesses as well. This research suggests that a new distribution channel, called a "foothold style Kosa mart," that cooperates jointly with a distribution center and a large discount mart can provide direct solutions to small and mid-size distributors. This new distribution channel can achieve a limited type of "Nadle shop (small supermarket) foster project" related to building a joint distribution center and improvement in wholesale supply. Research design, data, and methodology - Data about the Korea distribution situation, the Nadle stores, and the logistics centers were collected from literature, Statistics Korea, journals, and reports. Specifically, we investigated information about Kosa Mart and Nadle stores. We focused on the redesign of the distribution center for the Nadle store. Results - The Kosa Mart distribution center now includes 18 warehouses, and has been handling 2000-3000 items. Most of the warehouses have been simply designed and items loaded and stored without refrigeration; thus, it is possible to store only products of certain manufactured goods. The current logistics center has no wholesale function because it failed to resolve the joint purchasing and product supply issues of competitively priced products. Conclusions - This study aimed to identify ways to strengthen the competitiveness of small- and medium-sized retailers. A Kosa Mart redesign aims to unifying the logistics center, stores, and customers. First, the joint wholesale logistics system, equipped with an integrated ordering system, needs to process customer orders and store orders at the same time. Second, excellent small business product development has to connect with production. Third, the store composition needs to support a shipping hub. Fourth, the Mart differentiates itself from convenience store goods by supplying regional and specialized products to customers. Fifth, a service buying agent and direct transactions between producers and consumers need to be established, and exhibits and displays of goods need to be improved.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.11
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• pp.54-61
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• 2003

In this paper, an efficient non-scan design-for-testability (DFT) method for controller circuits is proposed. The proposed method always guarantees a short test pattern generation time and complete fault efficiency. It has a lower area overhead than full-scan and other non-scan DFT methods and enables to apply test patterns at-speed. The proposed method also shortens the test application time through a test pattern re-ordering procedure. The efficiency of the proposed method is demonstrated using well known MCNC'91 FSM benchmark circuits.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.2 s.314
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• pp.27-36
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• 2007

Changeable biometrics identify a person using transformed biometric data instead of original biometric data in order to enhance privacy and security in biometrics when biometric data is compromised. In this paper, a novel scheme which generates changeable face templates for statistical appearance-based face recognition is proposed. Two different original face feature vectors are extracted from two different appearance-based approaches, respectively, each original feature vector is normalized, and its elements are re-ordered. Finally a changeable face template is generated by weighted addition between two normalized and scrambled feature vectors. Since the two feature vectors are combined into one by a two to one mapping, the original two feature vectors are not easily recovered from the changeable face template even if the combining rule is known. Also, when we need to make new changeable face template for a person, we change the re-ordering rule for the person and make a new feature vector for the person. Therefore, the security and privacy in biometric system can be enhanced by using the proposed changeable face templates. In our experiments, we analyze the proposed method with respect to performance and security using an AR-face database.

• Archives of design research
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• no.18
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• pp.165-174
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• 1996

In the I950s the German firm Braun began to pursue a policy of uncompromising modem design for products aimed at the upper reaches of the market. Dr. Fritz Eichler as a head of design with Hans Gugelot and Otl Aicher in the Graduate School VIm developed the guide line of Braun Design strategy as the foundation of the corporate identity programme. In 1955 Dieter Rams joined the staff, and was largely responsible for establishing the formal characteristics of Braun Design and its further development. In the mid-1950s complete product programme of the firm Braun began to be re-designed, and these undoubtedly hit the market. New design line of the firm Braun, was an exclusive avantgarde movement at that time, which became to be the epitome of the idea of an objectifiable "Good Form". By the result in the 60s and 70s, when Braun product program was completely re-designed to the new line, Braun Design had a decisive influence on the design scene of the world. Braun Design is essentially functional and concrete, which depends on perfect fulfillment of purpose, precision, safety, durability, the quality of the product and, more recently, environmental compatibility is similarly balanced and unified approach, eliminating every unnecessary detail and concentrating on ordering essential elements. elements.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.1
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• pp.48-59
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• 2009

Next generation mobile communication system will have various access networks and provide seamless multimedia data service to mobile nodes. The WiNGS system, one of these access network, has superior RAT(Radio Access Technology) and network connectivity other than previous ones. In this paper, we propose link-layer SR-ARQ between mobile node and WAGW to solve packet re-ordering problem during handover. In the proposed scheme, we apply the adaptive timer at the SR-ARQ sender to reduce unnecessary packet retransmission during handoff and delayed NAK algorithm at the SR-ARQ receiver for delaying NAK response due to temporary out-of-sequenced frames. We evaluate the performance of the proposed scheme by implementing the new SR-ARQ protocol at the link-layer using ns-2 simulator, and show the handover performance is improved greatly by preventing unnecessary retransmission.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.429-436
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• 2017

A design thinking-based collaborative workshop in which various stakeholders in the milk processing industry circulation ecosystem participated shows a new problem innovation paradigm that encourages the spread of practical prototyping culture. in the expression of empathy and collective intelligence among members on facing issues, the conversion of collaboration and communication methods, the business handling of the organization based on the design work method as 'creativity mechanism'. In this workshop, which was promoted in three stages of 'approach to problems', 're-definition of problems', and 'experience-based future vision design', participants themselves redefine real problems in terms of the accuracy of feed orders between feed suppliers and livestock farmers, ordering of feeds on time, cost reduction of feed supply and present new alternatives and expanded business areas. The results suggested in this workshop suggest the usefulness of design thinking in business innovation in that they presented how to approach the problem and a creative thinking system to find its solution to direct and indirect stakeholders of the industry as well as the improvement of supply and demand rate of livestock feed and quality.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1999.04a
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• pp.426-426
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• 1999

;There are many sources of uncertainty in a typical production and inventory system. There is uncertainty as to how many items customers will demand during the next day, week, month, or year. There is uncertainty about delivery times of the product. Uncertainty exacts a toll from management in a variety of ways. A spurt in a demand or a delay in production may lead to stockouts, with the potential for lost revenue and customer dissatisfaction. Firms typically hold inventory to provide protection against uncertainty. A cushion of inventory on hand allows management to face unexpected demands or delays in delivery with a reduced chance of incurring a stockout. The proposed strategies are used for the design of a probabilistic inventory system. In the traditional approach to the design of an inventory system, the goal is to find the best setting of various inventory control policy parameters such as the re-order level, review period, order quantity, etc. which would minimize the total inventory cost. The goals of the analysis need to be defined, so that robustness becomes an important design criterion. Moreover, one has to conceptualize and identify appropriate noise variables. There are two main goals for the inventory policy design. One is to minimize the average inventory cost and the stockouts. The other is to the variability for the average inventory cost and the stockouts The total average inventory cost is the sum of three components: the ordering cost, the holding cost, and the shortage costs. The shortage costs include the cost of the lost sales, cost of loss of goodwill, cost of customer dissatisfaction, etc. The noise factors for this design problem are identified to be: the mean demand rate and the mean lead time. Both the demand and the lead time are assumed to be normal random variables. Thus robustness for this inventory system is interpreted as insensitivity of the average inventory cost and the stockout to uncontrollable fluctuations in the mean demand rate and mean lead time. To make this inventory system for robustness, the concept of utility theory will be used. Utility theory is an analytical method for making a decision concerning an action to take, given a set of multiple criteria upon which the decision is to be based. Utility theory is appropriate for design having different scale such as demand rate and lead time since utility theory represents different scale across decision making attributes with zero to one ranks, higher preference modeled with a higher rank. Using utility theory, three design strategies, such as distance strategy, response strategy, and priority-based strategy. for the robust inventory system will be developed.loped.

• Journal of Elementary Mathematics Education in Korea
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• v.13 no.1
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• pp.75-95
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• 2009

The purpose of the study was to investigate the scaffolding processes of children in mathematical problem solving. 3 groups of 4th grade students participated in the study and the researchers proceeded the study for 4 months. The procedures of this research were as followings. First, when the learners solved the problems, the categories of scaffolding processes(by way of unit line coding belong in open codings, the categories were made 25 concepts and integrated 20 subcategories) were produced the 7 results: invite to the learning, set the problems, affective aids, attempt self learning, re-ordering between learners and affirmation self learning. Second, the processes of scaffolding in mathematic problem solving resulted in condition, the present condition, action/interaction and the outcomes. Third, the cognitive and affective aids that discovered in the scaffolding processes were considered the main categories of learner's scaffolding processes in solving the mathematic problems. In conclusion, first, the learners' scaffolding processes, based on Vygotsky's "the zone of proximal development" in selection and presentation of mathematic problems, are very diverse. Peers' affective aids are very important in solving the problems. Second, learners in the scaffolding processes exchange the cognitive and affective aids with each other with joy and earnestness, and the aids can give assistance to all the participants. Third, in the results of observation and analysis in learners' scaffolding processes, it is meaningful to know how they think. Finally, the learners' scaffolding processes are a little unsystematic and illogical compared to those of adults, but those of scaffolders are so similar to those of learners' cognitive and affective systems that they can provide teachers with many merits in understanding and teaching learners.