• Ocean Systems Engineering
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• v.10 no.2
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• pp.163-179
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• 2020

Considering the huge demand of several types of subsea equipment, as Christmas Trees, PLEMs (Pipeline End Manifolds), PLETs (Pipeline End Terminations) and manifolds for instance, a critical phase is its installation, especially when the equipment goes down through the water, crossing the splash zone. In this phase, the equipment is subject to slamming loads, which can induce impulsive loads in the installation wires and lead to their rupture. Slamming loads assessment formulation can be found in many references, like the Recommended Practice RP-N103 from DNV-GL (2011), a useful guide to evaluate installation loads. Regarding to the slamming loads, RP-N103 adopt some simplifying assumptions, as considering small dimensions for the equipment in relation to wave length, in order to estimate the slamming coefficient C_S used in load estimation. In this article, an experimental investigation based on typical subsea structure dimensions was performed to assess the slamming coefficient evaluation, considering a more specific scenario in terms of application, and some reduction of the slamming coefficient is achieved for higher velocities, with positive impact on operability.

• Journal of Korean Library and Information Science Society
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• v.19
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• pp.59-81
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• 1992

This study investigates Japanese-made Chinese Characters in JIS X 0212-1990(Code of the Su n.0, pplementary Japanese Graphic Character Set for Information Interchange). As a results of detailed investigation, it is found that the number of Japanese-made Chinese Characters in su n.0, pplementary set reaches to 69 characters. Among them, 29 characters are not listed even in the best known chinese character dictionary [대한화사전]. 30 characters are found in the chinese character dictionaries published in Korea, while 39 characters are not found in any of those dictionaries. The distinctive characteristic of Japanese-made Chinese characters is that those chinese characters are made in order to name the things, such as fishes, birds, trees, which do not have Chinese-made Chinese Characters.

• Korean Journal of Pharmacognosy
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• v.2 no.2
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• pp.99-118
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• 1971

The flora of Mt. Du Ryun were investigated by the authors from November 3, 1955 to July 21, 1970. 1) Mt. Du Ryun is located at Heanam-Gun, Junla-Nam Do, Korea (between longitude $126^{\circ}\;35'\;E$ and $126^{\circ}40'{\;}E$, and between $34^{\circ}25'$ N.L. and $34^{\circ}30'$ N.L. on the latitude.). Average temperature is $14.1^{\circ}C$, and precipitation per annum 1,488.7mm. 2) On the whole, the observed floral region consisted of 5 formas, 56 varieties, 770 species, 440 genera, 159 families, in 86 orders. 3) The medicinal plants in the area include 321 species, 242 genera and 120 families. 4) The region includes 2 formas, 7 varieties, 30 species in 24 families of evergreen trees. It was pointed out that this area is a typical warm zone in the Korean flora.

• Journal of Information Processing Systems
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• v.13 no.1
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• pp.104-113
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• 2017

In this paper, we present an approach to transmit data from the source to the destination through a minimal path (least-cost path) in a computer network of n nodes. The motivation behind our approach is to address the problem of finding a minimal path between the source and destination. From the work we have studied, we found that a Steiner tree with bounded Steiner vertices offers a good solution. A novel algorithm to construct a Steiner tree with vertices and bounded Steiner vertices is proposed in this paper. The algorithm finds a path from each source to each destination at a minimum cost and minimum number of Steiner vertices. We propose both the sequential and parallel versions. We also conducted a comparative study of sequential and parallel versions based on time complexity, which proved that parallel implementation is more efficient than sequential.

• Research in Plant Disease
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• v.29 no.3
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• pp.299-303
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• 2023

Rust symptoms on Meliosma myriantha trees have been noticed during disease surveys in Korea since 2010, with a high disease incidence frequently surpassing 90%. The causal fungus of the rust disease was identified as Neophysopella vitis based on the morphological investigation and molecular sequence analysis of the internal transcribed spacer (ITS) and large subunit (LSU) rDNA regions. This is the first report of rust disease caused by N. vitis on M. myriantha in Korea. A pathogenicity assay proved that M. myriantha serves as the aecial host of N. vitis as spermogonia and aeciospores were produced, which can infect the two uredinial hosts, Boston ivy (Parthenocissus tricuspidata) and Virginia creeper (Parthenocissus quinquefolia).

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.3
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• pp.149-157
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• 2009

The crossed cube, a variation of the hypercube, possesses a better topological property than the hypercube in its diameter that is about half of that of the hypercube. It has been known that an N-node complete binary tree is a subgraph of an (N+1)-node crossed cube [P. Kulasinghe and S. Bettayeb, 1995]. However, efficient embedding methods have not been known for the case that the number of nodes of the complete binary tree is greater than that of the crossed cube. In this paper, we show that an N-node complete binary tree can be embedded into an M-node crossed cube with dilation 1 and load factor [N/M], N>M$\geq$2. The dilation and load factor is optimal. Our embedding has a property that the tree nodes on the same level are evenly distributed over the crossed cube nodes. The property is especially useful when tree-structured algorithms are processed on a crossed cube in a level-by-level way.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.254-263
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• 1988

Contents and distribution of amino acids in the humic acid and fulvic acid fractions of different types ($R_p$, B, A, P) were investigated. Extracted humic and fulvic acids were purified and analyzed. The results are summarized as the following: (1) Composition of Humus The total humus ($H_T$), amount of humic acid (a), amount of fulvic acid (b), and ${\Delta}logK$ all decrease in the order of $R_p$ > B > A > P type. The same trend was observed in the total nitrogen and carbon. (2) Contents and composition of amino acids in humic acids. 1) The total amounts of amino acids in the humic acid fraction of different types were in the following order for soils under coniferous forest trees: $R_p$ > B > A > P type, but for soils under deciduous forest trees the order was P > A > $R_p$ > B type. There were positive correlationships between total amino acids and total carbon and ${\Delta}logK$ for humic acids from soils under coniferous forest trees, but a negative correlationship was existed. between total amino acids and C/N ratios. No significant correlation was found for samples taken from soils under deciduous forest trees. 2) The ratios of one group of amino acids to the others were compared. The ratios of acidic amino acids were in the order of P > $R_p$ > B > A type. those of neutral amino acids followed the order of $R_p$ > B > A > P type and those of the basic amino acids were in the order of B > A >$R_p$ > P type for soils under coniferous forest trees. Contents of total amino acids were in the order of the neutral > the acidic > the basic amino acids. For the soils under deciduous forest trees the order of the ratio was different. Acidic amino acids followed the order of A > P > B > $R_p$ type, neutral ones followed the order of P > $R_p$ > A > B type, and the basic amino acids did the order of $$P{\geq_-}$$ A > B $$\geq_-$$ $-R_p$ type where the difference was very small. 3) In general aspartic aicd, glycine and glutamic acid were the major components in all samples. Histidine, tyrosine and methionine belonged to the group contained in a small amount. (3) Contents and composition of amino acids in fulvic acids. 1) The total amounts of amino acids of different types of fulvic acids were in the order of $R_p$ > B > P > A type regardless of origin of samples. There were positive correlationships observed between the toal amino acids and total carbon and ${\Delta}logK$ for soils under coniferous forest trees. For soils under deciduous forest trees, positive correlationships were observed among total amino aicds, total nitrogen, total humus ($H_T$), total humic aicd (a), and ${\Delta}logK$, but a negative correlationship existed between total amino acids and C/N ratio. 2) Thr ratio among acidic amino acids, neutral amino acids and basic amino acids of different types were $R_p$ > B > P > A type. In this respect there was no difference between the two soils. 3) In general glycine, aspartic acid, and alanine were the major constituents in all samples of different types, while tyrosine and methionine were contained in a small amount. Virtually no amount of arginine was measured.

• Journal of Biosystems Engineering
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• v.20 no.3
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• pp.245-249
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• 1995

In this study power requirements to saw shoots with circular saw were determined by measuring and analyzing the required maximum torque to provide the information for the mechanization of Korean pine cone harvest. Two levels of feed rate of shoots, 10.4mm/s and 20.8mm/s, three levels of sawing speed 5.8㎧, 11.6㎧, and 17.4㎧, and 14 levels of shoot diameter from 7.7 to 18.1mm were used as variables. 1) The maximum torques were significantly affected by all three variables. The average maximum torque, 18.2 N-cm for feed rate of 20.Bmm/s was greater as much as 80% of 10.1 N-cm for feed rate of 10.4mm/s. 2) As the sawing speed was increased from 5.8㎧ to 11.6㎧ and 17.4㎧, the maximum torques were decreased to 14.8N-cm, 8.5N-cm, and 7.IN-cm, respectively when the feed rate was 10.4mm/s. The maximum torque ranged from 4.5 to 19.3N-cm as shoot diameter increased from 7.7 to 18.1mm. The minimum power requirements to saw shoots of 18.1mm with circular saw was 30W for the feed rate of 10.4mm/s. 3) The maximum torques were 28.6N-cm, 14.6N-cm, and 11.4N-cm when sawing speeds were 5.8㎧, 11.6㎧, and 17.4㎧, respectively when the feed rate was 20.8mm/s and these torques were increased as much as 93%, 36%, and 61% of those for the feed rate of 10.4mm/s. The maximum torque increased from 9.7N-cm to 30.7N-cm as shoot diameter increased from 7.7 to 18.1mm. The minimum power requirements to saw shoots of 18.1mm was 54W which was 1.8 times of 30W for the feed rate of 10.4mm/s.

• The KIPS Transactions:PartA
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• v.11A no.6
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• pp.459-468
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• 2004

Sharing XML trees on mobile devices has become more and more popular. Optimistic replication of XML trees for mobile devices raises the need for reconciliation of concurrently modified data. Especially for reconciling the modified tree structures, we have to compare trees by node mapping which takes O($n^2$) time. Also, using semantic based conflict resolving policy is often discussed in the literature. In this research, we focused on an efficient reconciliation method for mobile environments, using edit scripts of XML data sent from each device. To get a simple model for mobile devices, we use the XML list data sharing model, which allows inserting/deleting subtrees only for the repetitive parts of the tree, based on the document type. Also, we use keys for repetitive part subtrees, keys are unique between nodes with a same parent. This model not only guarantees that the edit action always results a valid tree but also allows a linear time reconciliation algorithm due to key based list reconciliation. The algorithm proposed in this paper takes linear time to the length of edit scripts, if we can assume that there is no insertion key conflict. Since the previous methods take a linear time to the size of the tree, the proposed method is expected to provide a more efficient reconciliation model in the mobile environment.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.24-29
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• 2013

This study was carried out for preliminary feasibility review to investigate work efficiency of chestnut harvest using yield net and to find a way to reduce the cost for purchasing and managing yield net. To this end, we conducted a survey of 6 forest farm houses in Cheongyang, Gongju and Buyeo regions where yield nets are being used efficiently. Cost-benefit analysis based on Net Present Value and Benefit Cost Ratio was used to examine the investment profitability. While regions of Cheongyang A, Cheongyang B and Buyeo A are profitable in spite of no subsidy for purchasing yield net from the government, the regions of Gongju A, Gongju B and Buyeo B are not profitable without subsidy. When an 80% of subsidy for purchasing yield nets is provided, the forest farm houses in Cheongyang A, Cheongyang B, Buyeo A and Gongju B regions are found to be profitable while those in Gongju A and Buyeo B regions are still not profitable. We consider that the different results come from the differences in the planting method of chestnut, labor efficiency, labor skill and the orchard conditions such as slop. Finally, several efforts for government and cultivator are suggested to expand the use of yield net; planting chestnut in line, establishing installation and management methods, supporting the cost for purchasing yield net and studying detailed effects besides profitability issue.