• Journal of the Korean Institute of Gas
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• v.10 no.1 s.30
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• pp.26-31
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• 2006

For the purpose of evaluating the availability of manifold safety devices installed in the LPG(Liquefied Petroleum Gas) refuelling stations, the quantitative analysis of the frequency on BLEVE(Boiling Liquid Expanding Vapor Explosion) scenario was performed. The amount of frequency reduction was the way of assessing safety devices availability. In this analysis, we could find out what sorts of safety devices are essential to satisfy acceptable social risk criteria and are prioritized to install in the future.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1442-1462
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• 2014

Packet classification is a key technology of the Internet for routers to classify the arriving packets into different flows according to the predefined rulesets. Previous packet classification algorithms have mainly focused on search speed and memory usage, while overlooking update performance. In this paper, we propose PreCuts, which can drastically improve the update speed. According to the characteristics of IP field, we implement three heuristics to build a 3-layer decision tree. In the first layer, we group the rules with the same highest byte of source and destination IP addresses. For the second layer, we cluster the rules which share the same IP prefix length. Finally, we use the heuristic of information entropy-based bit partition to choose some specific bits of IP prefix to split the ruleset into subsets. The heuristics of PreCuts will not introduce rule duplication and incremental update will not reduce the time and space performance. Using ClassBench, it is shown that compared with BRPS and EffiCuts, the proposed algorithm not only improves the time and space performance, but also greatly increases the update speed.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.57-64
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• 2007

Tree-ring dating can be used to date scientifically prehistoric timbers, historical buildings or woodcrafts. It gives a calendar year to each tree ring and produces the felling dates of logs or wood panels. In this study, we applied tree-ring dating to two medicine cabinets, known to be made in Kyônggi Province. Two cabinets were dated A.D. 1884 and 1874 to the last rings, respectively. Even with closed ages, two cabinets show different styles and structures. Tree-ring patterns indicated that the origins of woods for both cabinets would be near Sorak mountains and Kangneung area in Kangwon province.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.2
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• pp.139-149
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• 2012

A 3D stacked IC is made by multiple dies (possibly) with heterogeneous process technologies. Therefore, die-to-die variation in 2D chips renders on-package variation (OPV) in a 3D chip. In spite of the different variation effect in 3D chips, generally, 3D die stacking can produce high yield due to the smaller individual die area and the averaging effect of variation on data path. However, 3D clock network can experience unintended huge clock skew due to the different clock propagation routes on multiple stacked dies. In this paper, we analyze the on-package variation effect on 3D clock networks and show the necessity of a post silicon management method such as body biasing technique for the OPV induced 3D clock skew control in 3D stacked IC designs. Then, we present a parametric yield improvement method to mitigate the OPV induced 3D clock skew.

• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.32-36
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• 1996

Various culture conditions for cell growth and berberine production in cork tree (Phellodendron amurense Rupr.) were investigated. Callus was induced from cambium tissue of cork tree, and cultured on LS liquid medium supplemented with 0.5 mg/1 2,4-D, 0.1mg/1 BA, and 3% sucrose. Several factors enhancing berberine production and cell growth in cork tree cell cultures were found. Some of them enhanced both cell growth and berberine production, but others resulted in a decoupling of cell growth and berberine production with significant in the specific levels. High level of nitrate (80mM), high level of phosphate (8.98mM), and sucrose (7%), 1.0mg/l IAA were effective in berberine production, whereas low level of nitrate (40mM), and phosphate (2.25mM), and high level of sucrose (7%) in the medium were effective in cell growth. Two stage culture(first stage for cell growth, and second stage for berberine production) increased berberine production almost twice (5.06mg/g dry weight) as much as single stage cultures in berberine production.

• STI Policy Review
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• v.8 no.2
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• pp.75-93
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• 2017

Recently, global competition in the manufacturing sector is driving firms in the manufacturing sector to conduct product innovation projects to maintain their competitive edge. The key points of product innovation projects are 1) what the purpose of the project is and 2) what expected results in the target market can be achieved by implementing the innovation. Therefore, this study focuses on the performance of innovation projects with a business viewpoint. In this respect, this study proposes the "achievement rate" of product innovation projects as a measurement of project performance. Then, this study finds the best strategies from various innovation activities to optimize the achievement rate of product innovation projects. There are three major innovation activities for the projects, including three types of R&D activities: Internal, joint and external R&D, and five types of non-R&D activities - acquisition of machines, equipment and software, purchasing external knowledge, job education and training, market research and design. This study applies decision tree modeling, a kind of data-mining methodology, to explore effective innovation activities. This study employs the data from the 'Korean Innovation Survey (KIS) 2014: Manufacturing Sector.' The KIS 2014 gathered information about innovation activities in the manufacturing sector over three years (2011-2013). This study gives some practical implication for managing the activities. First, innovation activities that increased the achievement rate of product diversification projects included a combination of market research, new product design, and job training. Second, our results show that a combination of internal R&D, job training and training, and market research increases the project achievement most for the replacement of outdated products. Third, new market creation or extension of market share indicates that launching replacement products and continuously upgrading products are most important.

• Korean Journal of Environment and Ecology
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• v.28 no.4
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• pp.457-471
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• 2014

This study aims to present an evaluation scheme to improve the problems in tree shapes and tree growth which were identified through shape and growth assessments of landscape trees currently planted in Haedoji Park, Songdo, Incheon Metropolitan City after plant structure status and propriety review for funtion of space and concept of planting. Suitability the planting concept was evaluated according to function of space. The result indicated that the shade planting areas accounted for 29.5% of the the shade spaces area. 58.7%, respectively planting areas of visual landscape. And 11.8%, respectively planting areas of buffer. Because the planting areas was lacked according to the park established spatial configuration of central facilities and the result of plant young trees. Plant structure status required consideration with plant structure, density, size, growth status for improve planting function. The tree assessment was performed on a total of 28 species and 600 trees of which 22 species and 209 trees were planted in the buffer zone, 8 species and 71 trees in the shade zone, 16 species and 266 trees in the visual landscape zone, and 4 species and 54 trees in the ecological landscape zone. The trees were divided into grades based on their assessment score and were statistically grouped by the functional zone in where they are planted and by tree species to verify their significance. The tree shape assessment was an average of 56.6 points and the tree growth assessment was an average of 76.0 points. Using the results of the tree assessments, the tree standards for each functional space were identified and a concept of optimum planting and cultivating was applied. When applying the shape assessment results by zone to the concept of planting, since trees for buffering require high functionality they received E's, the lowest grade; as trees for ecological landscaping require diverseness and naturalness, they received D's; since trees for shading require utilization, they received C's as trees with branching at the main stems were considered; and since trees for visual landscaping required aesthetical value, they received A's and B's. When applying the growth assessment results by zone to the concept of planting, based on planting foundations of favorable and poor, for buffering, visual landscaping, and ecological landscaping, trees from grades A to E could be planted, and for shading, trees from grades A to C could be planted. For a cultivation plan that could improve the growth of the trees, we proposed that the topography of the land be selected considering the tree's characteristics and that a method of pot seeding be used. Also, to improve the shape of the trees, we proposed that poles be used to improve the growth of vertically-straight stems, an appropriate planting density be applied for reasonable branch growth, manage tree shape to maintain good crowning, and better manage fertilization to maintain a reasonable crown density.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.409-414
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• 1995

This study was carried out for the analysis and comparison about the noise diminution effects by the height, width and density of Euonymus japonica wall, the distance of sound source, the distance of sound receiver, the height of sound source, and the height of sound receiver. The results obtained were summarized as follows; 1. After the establishment of tree wall, the volume of noise diminution measured 6.8dB and the effects of noise diminution measured heigher than before by 10.6% and t-value was significant at the 1% level 2. In simple correlation between the effects of noise diminution and variables, the density of tree wall was found as the most significant factor, and the last were found in the order of the distance of sound receiver, the width of tree wall, and the distance of sound source. 3. In partial correlation coefficients the effects of noise diminution and variables, the density of tree wall (r=-0.959) was found as the most significant factor, and the last were found in order of the distance of sound receiver (r=-0.906) and the width of tree wall (r=-0.753). 4. The estimated equation to measure the effects of noise diminution according to variables (the height of tree wall, the width of tree wall, the density of tree wall, the distance of sound source, the distance of sound receiver, the height of sound source, and the height of sound receiver) was $Y=69.520-1.672X_1-1.656X_2-0.066X_3-0.248X_4-3.134X_5-0.222X_6-0.343X_7$, and the coefficient of determination of this estimated equation was highly found as 0.950. 5. In semi-partial correlation coefficient the effects of noise diminution were found in the order of the density of tree wall, the distance of sound receiver, the width of tree wall, and the height of tree wall from the highest to the lowest. Therefore, it was considered that the density of tree wall, the distance of sound receiver, the width of tree wall and the distance of sound source should be controlled effectively to increase the effects of noise diminution by Euonymus japonica wall.

• Communications for Statistical Applications and Methods
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• v.16 no.4
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• pp.579-586
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• 2009

We have used multifactor dimensionality reduction(MDR) method to study interaction effect of statistical model in general. But MDR method cannot be applied in all cases. It can be applied to the only case-control data. So, two methods are suggested E-MDR and D-MDR method using regression tree algorithm and dummy variables. We applied the methods on the identify interaction effects of single nucleotide polymorphisms(SNPs) responsible for longissimus mulcle dorsi area(LMA), carcass cold weight(CWT) and average daily gain(ADG) in a Hanwoo beef cattle population. Finally, we compare the results using permutation test.

• Korean Journal of Plant Taxonomy
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• v.35 no.3
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• pp.175-186
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• 2005

Cladistic analysis was performed to reveal the interspecific relationship of nine taxa of Korean Diplazium (Woodsiaceae). A total of 29 taxa with 20 taxa of eastern asiatic species as ingroup and three taxa of Athyrium as outgroup, were analyzed with 17 morphological characters. Diplazium nipponicum, recently found from Jeju Island, was most closely related to D. chinense by having the acuminate apex of pinnule segment and fascicled fronds. Diplazium nipponicum was distinguished from D. chinense by having scales and pinnule segments of serrated margin, and non-overlapped pinnules. Diplazium nipponicum and D. chinense were closely related to D. mesosorum and D. hajizoense in sequence, by having long acute apex in pinnae. These species formed same clade with D. subtripinnatum, which is endemic to Japan and D. kawakamii, which is distributed in Japan and Taiwan.