• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.479-488
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• 2001

As the SoC designs complexity constantly increases, the simulation that uses their software models simply takes too much time. To solve this problem, FPGA-based logic emulators have been developed and commonly used in the industry. However, FPGA-based logic emulators are facing with the problems of which not only very low FPGA resource usage rate due to the very limited number of pins in FPGAs, but also the emulation speed getting slow drastically as the complexity of designs increases. In this paper, we proposed a new innovative emulation architecture and its software that has high FPGA resource usage rate and makes the emulation extremely fast. The proposed emulation system has merits to overcome the FPGA pin limitation by pipelined ring which transfers multiple logic signal through a single physical pin, and it also makes possible to use a high speed system clock through the intelligent ring topology. In this topology, not only all signal transfer channels among EPGAs are totally separated from user logic so that a high speed system clock can be used, but also the depth of combinational paths is kept swallow as much as possible. Both of these are contributed to achieve high speed emulation. For pipelined singnals transfer among FPGAs we adopt a few heuristic scheduling having low computation complexity. Experimental result with a 12 bit microcontroller has shown that high speed emulation possible even with these simple heuristic scheduling algorithms.

• Journal of Marine Life Science
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• v.5 no.2
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• pp.99-106
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• 2020

To investigate effect of variation in physiochemical conditions due to river discharge on phytoplankton, field surveys were conducted in the Seomjin and Yeongsan River estuaries from April to November 2016. The concentrations of DIN and DSi in Seomjin River estuary were gradually low as distance from upstream. On the other hands, the concentrations of DIN and DSi in Yeongsan River estuary were critically high at upstream, due to which is characterized as semi-enclosed eutrophic area. A total of 12 phytoplankton pigments were analyzed, and the distribution of each taxa was investigated using indicator for each phytoplankton taxa. Fucoxanthin, an indicator pigment of diatoms, showed an average of 0.61±1.00 ㎍ l^-1 and 0.76±1.22 ㎍ l^-1 in the Seomjin and Yeongsan River estuaries, respectively. Concentration of fucoxanthin was more than twice that of other pigments except chlorophyll a., indicating that diatoms were dominant taxa. Peridinin, an indicator pigment of dinoflagellate, showed some similar tendency to the microscopic observation, but mismatch results were also present, indicating a technical limitation of pigment analysis. Chlorophyll b, alloxanthin, and zeaxanthin, which are indicator pigments of green algae, cryptomonads, and cyanobacteria, were detected in both estuaries even though those taxa were not detected in microscopic observation. This indicates that the two estuaries were affected by freshwater species. Here, we can suggest that phytoplankton composition in estuary was directly influenced by the inflow from upstream. In particular, the phytoplankton population dynamics in Yeongsan River estuary was greatly associated with a large-scale artificial dyke, especially in summer rainy season. On the other hands, the seasonal and horizontal distribution of phytoplankton in Seomjin River estuary has changed along the salinity gradients and inflow-related changes.

• Journal of Internet of Things and Convergence
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• v.9 no.1
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• pp.71-76
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• 2023

Recently, in order to store and manage big data, research and development of a high-performance storage system capable of stably accessing large data have been actively conducted. In particular, storage systems in data centers and enterprise environments use large amounts of SSD (solid state disk) to manage large amounts of data. In general, SSD uses FTL(flash transfer layer) to hide the characteristics of NAND flash memory, which is a medium, and to efficiently manage data. However, FTL's algorithm has a limitation in using DRAM more to manage the location information of NAND where data is stored as the capacity of SSD increases. Therefore, this paper introduces FTL policies that apply virtual memory to reduce DRAM resources used in FTL. The virtual memory-based FTL policy proposed in this paper manages the map data by using LRU (least recently used) policy to load the mapping information of the recently used data into the DRAM space and store the previously used information in NAND. Finally, through experiments, performance and resource usage consumed during data write processing of virtual memory-based FTL and general FTL are measured and analyzed.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.1
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• pp.52-62
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• 2008

As various types of embedded devices are widely used, a technology that supports reuse of applications on multiple platforms is needed in order for time-to-market development of the applications. The interface middleware is one of such technology and it hides platform dependency from application programmers. Existing interface middleware such as the MT project, Xenomai and Legacy2linux have limitation in that the APIs provided by each of these middleware are fixed to a specific operating system, and the middleware does not provide dynamic expansion of its API set. In this paper, we propose a middleware which hides operating system dependencies and enables porting of applications on various operating systems. In addition, the middleware has scalable structure so that it is suitable for resource-limited embedded systems. The overhead of the middleware, i.e., the time delay occurred by the middleware is between $0.3{\mu}sec\;and\;5{\mu}sec$ in most cases. We believe that the amount of overhead is reasonable and does not hurt the performance of applications.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.1
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• pp.155-163
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• 2014

To enhance network efficiency, content-centric networking (CCN) proposes that intermediated network nodes on a content-delivery path temporally cache transmitted contents. Then if an intermediated node receives a content request message (Interest) for previously cached content, the node directly transmits the cached content as a response message (Data) to requestors and finishes the transmission of the received Interest. Since Interest is performed by intermediated network nodes, it is possible to efficiently transmit contents and to effectively solve a network congestion problem caused around contents sources. For that, CCN utilizes both content store to temporarily cache content and pending Interest table (PIT) to record Interest incoming Face. However, it has mentioned the possibility of denial service attack using both the limitation of PIT resource and fake Interests. In this paper, we briefly describe the presented PIT flooding attack utilizing fake Interest. Then we introduce new attack possibility using fake Data and propose a countermeasure for the proposed attack. Also we evaluate the performance of our proposal.

• The Journal of the Korea Contents Association
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• v.14 no.4
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• pp.513-521
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• 2014

The purpose of this research is to develope and implement a convergent educational contents based on theoretical background of integrated education using agent based modeling in the ubiquitous learning environment. The structure of this contents consists of three modules that were designed by trans-disciplinary concept and situated learning theory. These three modules are: convergent problem presenting module, resource of knowledge module and learning of agent based modeling and IT tools module. After the satisfaction survey of the implemented content, out of 5 total value, the average value was 3.86 for effectiveness, 4.13 for convenience and 3.86 for design. The result of the survey shows that the users are generally satisfied. By using this u-learning contents, learners can experience and learn how to solve the convergent problem by utilizing IT tools without any limitation of device, time and space. At the same time, the proposal of structural design of contents can be a good guideline to the researchers to develop the convergent educational contents in the future.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.133-139
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• 2015

This study is aimed at suggesting the establishment strategy of human resource development through the tax support system under the "Tax incentive limitation law" provided for job creation and employment retention, by which the improvement measurements for utility maximization. The study results are briefly summarized as follows: At first, It's necessary to permit overlapping deduction of the tax favor for encouragement of job creation and employment retention, i.e. tax exemption and tax credit, and to exclude a company from the object for the alternative minimum tax application for maximization of the effect on employment inducement. Secondly, It's necessary to establish tax exemption and a tax credit on the surplus of the minimum wage standard. At last, It's also necessary to abolish, or expand the sunset period of tax support on a large scale to enhance the predictability of human resources management. These discussion are made through the convergence both employment policies and tax laws.

• The Journal of Pediatrics of Korean Medicine
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• v.29 no.4
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• pp.29-38
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• 2015

Objectives We aimed to identify the effectiveness of photobiomodulation using low level laser therapy (LLLT), light emitting diode (LED) and others on the growth of the length of the growth plate by reviewing literatures. Methods We searched literatures using PubMed, Science Direct, CINAHL, Korea Traditional Knowledge Portal (KTKP), Oriental Medicine Advanced Searching Integrated System (OASIS), China Knowledge Resource Integrated Database (CNKI), Japan Science and Technology Information Aggregator, Electronic (J STAGE), and Japan National Institute of Informatics Scholarly and Academic Information Navigator (CiNii) using the keywords "Growth plate" "Epiphyseal growth" "Epiphyseal plate" and "Laser", "light emitting diode (LED)", "near-infrared light", and "photobiomodulation". Search range included only original article which provided English abstract were selected. The search strategy contained no language limitation. Results A total 556 studies were found. Then, 551 were excluded by scanning titles and abstracts and finally 5 articles were selected. Five articles were RCTs using rodents. Two of the 5 articles used InGaAlP Laser (630-685 nm), and the other 3 articles used GaAlAs Laser (780, 820, and 870 nm) to investigated the effects of LLLT on the growth of the length of the epiphyseal cartilage and the number of chondrocytes and thickness of each zone of the epiphyseal cartilage. Two articles concluded that LLLT had a beneficial effect on the longitudinal growth of the growth plate. In growth of the epiphyseal plate, there were no significant differences in others. Conclusions It is might that LLLT influenced on the growth of epiphyseal plate by positive affect. However, further rigorous RCTs are warranted.

• Journal of the HCI Society of Korea
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• v.2 no.1
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• pp.41-47
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• 2007

This study aims to empirically examine the effect of feedback on attention recovery. The role of feedback has been proven to be positive in particular to extend the limitation of attention resource. We studied the impact of feedback on attention by varying its type and modality. An experimental system was developed to observe how accurately the participants performed the pattern-matching task with differential feedback provided on a real-time basis based on the ADHD diagnostic model. Six university students participated in this study with 6 different feedback conditions and controlled conditions. The participants experienced the feedbacks before experiment. They was asked two hundred tasks in four feedback conditions. The difference of feedback effect according to different modality is to find within a subject. The results indicated that the combined feedback of cognitive with perceptual stimulus led better performance than the combined of perceptual feedbacks.

• The Journal of Fisheries Business Administration
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• v.38 no.2
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• pp.103-129
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• 2007

Prior research on the fishery village tourism has mainly focused on the development and activities in the field, but lacking in strategic approaches. To overcome such a limitation, this study intends to measure visitors' authenticity on Gijang Anchovy Festival, test reliability and validity of the measurement items, and to identify the relationships among variables by a regression analysis of visitors' satisfaction. Authenticity means the value of existence. The types of tourism in fishing villages have been classified as fishery tourism, resource tourism and ecotourism and each of them has its own authenticity. Based on previous research, this study classified it into three factors such as objective authenticity, experiential authenticity and inauthenticity. To analyze the current situation of Daebyeon Anchovy Festival, measurement scales were developed and survey was conducted on the visitors for the three days from April 20 to 23, 2007. A total of 211 questionnaires were distributed and 208 were collected, The questionnaire contains 25 items on authenticity and 4 items on satisfaction and all the items were measured on the 7 Likert scale. It also has 8 items on demographic characteristics. On the test of reliability and validity of the authenticity, 24 items were used, Cronbach's was 0.7 and correlation was higher than 0.3. Factors of objective authenticity, experiential authenticity and inauthenticity were drawn from the factor analysis, which means that the 24 items may be used to measure authenticity of fishery festivals. The findings show that the evaluation score was 4.89 for objective authenticity, 4.36 for experiential authenticity, and 4.24 for inauthenticity. On the test of the hypotheses, the path coefficients were estimated 0.087 for objective authenticity, 0.202 for experiential authenticity and 0.503 for inauthenticity on the visitors' satisfaction. This suggests some meaningful marketing strategies for Gijang Anchovy Festival. First of all, the anchovy festival should focus on motivating visitors to revisit the festival by identifying individual traits, making a pleasant festival oriented toward family visitors, and providing more experience programs about anchovy.