• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.1
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• pp.75-83
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• 2008

We propose a welfare interface using multiple fecial features tracking, which can efficiently implement various mouse operations. The proposed system consist of five modules: face detection, eye detection, mouth detection, facial feature tracking, and mouse control. The facial region is first obtained using skin-color model and connected-component analysis(CCs). Thereafter the eye regions are localized using neutral network(NN)-based texture classifier that discriminates the facial region into eye class and non-eye class, and then mouth region is localized using edge detector. Once eye and mouth regions are localized they are continuously and correctly tracking by mean-shift algorithm and template matching, respectively. Based on the tracking results, mouse operations such as movement or click are implemented. To assess the validity of the proposed system, it was applied to the interface system for web browser and was tested on a group of 25 users. The results show that our system have the accuracy of 99% and process more than 21 frame/sec on PC for the $320{\times}240$ size input image, as such it can supply a user-friendly and convenient access to a computer in real-time operation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.7
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• pp.31-40
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• 2004

In this paper, we analyze mathematically the performance of the gated service scheduling in the Interleaved Polling with Adaptive Cycle Time(IPACT) was proposed to control upstream traffic for Gigabit Ethernet-PONs. In the analysis, we model EPON MAC protocol as a polling system and use mean value analysis. We divide arrival rate λ into three regions and analyze each region accordingly In the first region in which λ value is very small, there are very few ONUs' data to be transmitted. In the second region in which λ has reasonably large value, ONUs have enough data for continuous transmission. In the third region, ONUs' buffers are always saturated with data since λ value is very large. We obtain average packet delay, average Queue size, average cycle time of the gated service. We compare analysis results with simulation to verify the accuracy of the mathematical analysis. Simulation requires much time and effort to evaluate the performance of EPONs. On the other hand, mathematical analysis can be widely used in the design of EPON systems because system designers can obtain various performance results rapidly. We can design appropriate EPON systems for varioustraffic property by adjusting control parameters.

• Hwankyungkyoyuk
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• v.19 no.1 s.29
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• pp.1-13
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• 2006

This study was aimed to explore the level of awareness of Korean teachers and college students towards sustainable development(SD) and education for sustainable development(ESD). A survey was conducted to understand the present status of awareness of SD and ESD among 317 college students and 625 teachers in Korea from April to May of 2005. The questionnaire included items asking whether they heard about terms such as sustainability or sustainable development, the source of information on SD, the level of understanding or the urgent task for SD in Korea. It also included questions about experiences in participating in or conducting ESD, the need for ESD, important areas in and the modality for ESD and the willingness to participate in ESD. The results showed that the level of awareness on SD among teachers was low compared to college students, who have a relatively high level of access on SD issues through textbooks and classes in high school. Interestingly, most of college students replied that they never received any ESD, even though they learned SD in class. Both the teacher and student group thought that tile priority of sustainable development should be an 'environment-related' area in the social, economical and environmental perspectives. Most of the students and teachers considered the concept of SD as 'pursuing the balance between environmental protection and economic development.' Some of the teachers recognized the concept of sustainable development in the paradigm of continuous economic development. Both groups responded that the urgent task related to sustainable development is 'environmental protection' and the 'reduction of poverty.' On the other hand, they had experiences in teaching related to natural resources, gender equity, health, human rights, climate changes and other SD issues in class, but not under the name of ESD. They also emphasized 'critical thinking and problem solving & decision-making' in education. Most of the students and teachers responded that it was needed to carry out ESD, and that the way of life for SD would be the priority. It is suggested that various pedagogy and modalities according to various target groups should be considered in providing ESD. It is necessary to use more effective strategies for ESD rather than just introducing the concept of SD. Also, it is needed to review the ESD practices of teachers and improve the quality of education within the scope of ESD.

• The Korean Journal of Financial Management
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• v.27 no.1
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• pp.121-156
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• 2010

Back-door-listing can be viewed both as M&A and an alternative to IPO. If IPO is an access to the capital market through regulations, back-door-listing would be the way of entering the market through trading. Back-door-listing can be a better choice considering the common wisdom that regulations hinder the functioning of free market system. One would, however, prefer IPO, for the informational asymmetry isless severe in case of IPO. This paper examines if IPO is superior to back-door-listing as to the informational efficiency. The excess buy-and-hold returns of the Kosdaq back-door-listing firms are estimated over the three-year-period since the event. They are compared against the excess buy-and-hold returns of the Kosdaq IPO firms over the same period of time. The results confirm this paper's prediction that IPO should be more information-efficient. Both IPO and back-door-listing firms start with high short-term excess returns and end up with long-term under-performance. However, back-door-listing firms show more significantly damaging long-term results. Furthermore, back-door-listing firms record poorer accounting results over the research period. These results imply that there exists fad at the time of both events and, in case of back-door-listing, this fad is reinforced by the possibility of window dressing.

• Journal of Environmental Policy
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• v.10 no.2
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• pp.3-19
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• 2011

Nagoya Protocol designed to establish criteria about material trade of biological genetic resources(ABS) was adopted in the 10th conference of the Parties to the Convention on Biological Diversity. In the course of the negotiation for adoption of the protocol, there was conflict between developed and developing countries, resource-rich and poor countries, and multinational corporations and environmentalists. This study investigates conflict process, subjects, issues and major factors in the negotiation case, and analyzes the negotiation by using the Conflict Management Process. To develope conflict management strategies for various conflict cases, we examine previous studies and analyze the intersectional conflict factors of this case and general cases, such as Fundamental side, Resource-allocation side, and Communication/Information-sharing side. These analyses of conflict prevention/resolution of the ABS negotiation show the importance of building mutual trust among stakeholders, enhancing mediator training, and constructing appropriate legislative/policy systems for successful conflict management.

• The Korean Journal of Air & Space Law and Policy
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• v.21 no.2
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• pp.97-121
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• 2006

Inter-Korean exchanges using civil aviation has been continuing since the temporary direct air route from Pyongyang to Seoul was opened on June 15th, 2000 for the summit meeting with North Korea. In this paper, I analyze the North Korea Aviation law by focusing on the differences with South Korean Aviation law. While South Korean Aviation law is modeled on the Pandect system, North Korean Aviation law can only be understood by looking at North Korea's socialist ideology. Therefore, North Korean Aviation law has some expressions which can hardly be understood. With respect to the source of aviation law, both South and North Korea are in compliance with the Convention on International Civil Aviation (Signed at Chicago, on 7 December, 1944). Thus, they established the aviation law based on the standards and recommendations provided by ICAO. For this reason, they have similar legal systems and composition. From this analysis, a few differences are also derived regarding aircraft ownership, airports, airline liability, aircraft accident investigation organization and aviation insurance. It is important to note that this paper has a particular limitation. Not only is the information about North Korean law very limited, but North Korea also does not provide easy access to its national legal codes. This paper describes the legal comparison of South and North Korea by focusing on the formation and framework of North Korean aviation law.

• Journal of KIISE:Software and Applications
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• v.31 no.4
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• pp.467-477
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• 2004

While recommender systems were used by a few E-commerce sites former days, they are now becoming serious business tools that are re-shaping the world of I-commerce. And collaborative filtering has been a very successful recommendation technique in both research and practice. But there are two problems in personalized recommender systems, it is First-Rating problem and Sparsity problem. In this paper, we solve these problems using the associative relation clustering and “Lift” of association rules. We produce “Lift” between items using user's rating data. And we apply Threshold by -cut to the association between items. To make an efficiency of associative relation cluster higher, we use not only the existing Hypergraph Clique Clustering algorithm but also the suggested Split Cluster method. If the cluster is completed, we calculate a similarity iten in each inner cluster. And the index is saved in the database for the fast access. We apply the creating index to predict the preference for new items. To estimate the Performance, the suggested method is compared with existing collaborative filtering techniques. As a result, the proposed method is efficient for improving the accuracy of prediction through solving problems of existing collaborative filtering techniques.

• The KIPS Transactions:PartD
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• v.18D no.3
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• pp.157-168
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• 2011

Recently flash memory has been being utilized as a main storage device in mobile devices, and flashSSDs are getting popularity as a major storage device in laptop and desktop computers, and even in enterprise-level server machines. Unlike HDDs, on flash memory, the overwrite operation is not able to be performed unless it is preceded by the erase operation to the same block. To address this, FTL(Flash memory Translation Layer) is employed on flash memory. Even though the modified data block is overwritten to the same logical address, FTL writes the updated data block to the different physical address from the previous one, mapping the logical address to the new physical address. This enables flash memory to avoid the high block-erase cost. A flashSSD has an array of NAND flash memory packages so it can access one or more flash memory packages in parallel at once. To take advantage of the internal parallelism of flashSSDs, it is beneficial for DBMSs to request I/O operations on sequential logical addresses. However, the B-tree structure, which is a representative index scheme of current relational DBMSs, produces excessive I/O operations in random order when its node structures are updated. Therefore, the original b-tree is not favorable to SSD. In this paper, we propose AS(Always Sequential) B-tree that writes the updated node contiguously to the previously written node in the logical address for every update operation. In the experiments, AS B-tree enhanced 21% of B-tree's insertion performance.

• The KIPS Transactions:PartC
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• v.14C no.5
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• pp.417-424
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• 2007

Mesh networks using WLAN technology have been paid attention as a key wireless access technology. However, many technical issues still exist for its successful deployment. One of those issues is the routing problem that addresses the path setup through a WLAN mesh network for the data exchanges between a station and a wired network. Since the characteristics of a WLAN mesh network can be very dynamic, the use of single routing protocol would not fit for all environments whether it is reactive or proactive. Therefore, it is required to develop an adaptive routing protocol that modifies itself according to the changes in the network parameters. As a logical first step for the development, an analytical model considering all the dynamic features of a WLAN mesh network is required to evaluate the performance of a reactive and a proactive routing scheme. In this paper, we propose an analytical model that makes us scrutinize the impact of the network and station parameters on the performance of each routing protocol. Our model includes the size of a mesh network, the density of stations, mobility of stations. and the duration of network topology change. We applied our model to the AODV that is a representative reactive routing protocol and DSDV that is a representative proactive routing protocol to analyze the tradeoff between AODV and DSDV in dynamic network environments. Our model is expected to help developing an adaptive routing protocol for a WLAN mesh network.

• The KIPS Transactions:PartA
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• v.19A no.1
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• pp.35-44
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• 2012

Traditional technologies that are used to improve the performance of hard disk drives show many negative cases if they are applied to solid state drives (SSD). Access time and block sequence in hard disk drives that consist of mechanical components are very important performance factors. Meanwhile, SSD provides superior random read performance that is not affected by block address sequence due to the characteristics of flash memory. Practically, it is recommended to disable prefetching if a SSD is installed in a personal computer. However, this paper presents a combinational method of a prefetching scheme and a memory management that consider the internal structure of SSD and the characteristics of NAND flash memory. It is important that SSD must concurrently operate multiple flash memory chips. The I/O unit size of NAND flash memory tends to increase and it exceeded the block size of operating systems. Hence, the proposed prefetching scheme performs in an operating unit of SSD. To complement a weak point of the prefetching scheme, the proposed memory management scheme adaptively evicts uselessly prefetched data to maximize the sum of cache hit rate and prefetch hit rate. We implemented the proposed schemes as a Linux kernel module and evaluated them using a commercial SSD. The schemes improved the I/O performance up to 26% in a given experiment.