• Journal of the Society of Naval Architects of Korea
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• v.43 no.1 s.145
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• pp.68-74
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• 2006

The welding distortion of a hull structure in the shipbuilding industry is inevitable at each assembly stage. This geometric inaccuracy caused by the welding distortion tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding distortion. The validity of the prediction method must be also clarified through experiments. For the purpose of reducing the weld-induced bending deflection, this paper proposes the mechanical tensioning method (MTM) as the optimum distortion control method. The validity of this method has been substantiated by a number of numerical simulations and actual measurements.

• Journal of IKEEE
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• v.23 no.2
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• pp.710-715
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• 2019

We consider parameter estimation in distributed systems in which measurements at local nodes are quantized in a non-regular manner, where multiple codewords are mapped into a single local measurement. For the system with non-regular quantization, to ensure a perfect independent encoding at local nodes, a local measurement can be encoded into a set of a great number of codewords which are transmitted to a fusion node where estimation is conducted with enormous computational cost due to the large cardinality of the sets. In this paper, we propose an efficient estimation technique that can handle the non-regular quantized data by efficiently finding the feasible combination of codewords without searching all of the possible combinations. We conduct experiments to show that the proposed estimation performs well with respect to previous novel techniques with a reasonable complexity.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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• pp.108-114
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• 2021

In this study, a multivariate function was applied to the genetic algorithm for D-type lugs currently used in shipyards to closely analyze the behavioral form of weight loss without double plates. An optimal lifting lug structure design without attachments is proposed. MATLAB R2016a was used to design features by applying multivariate functions to genetic algorithms. Furthermore, the design was achieved by deriving the optimal shapes of lugs using genetic algorithms. The shapes of the designed lugs were validated for structural bonding using the structural analysis program ANSYS 2020 R2, and a robust design of lugs with no appendages was developed.

• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2874-2879
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• 2020

Due to excess reactivity, fresh nuclear fuel often contains burnable poisons. This research looks at six different burnable poisons and their impacts on reactivity, material attractiveness, and waste management. An MCNP simulation of a PWR fuel pin was performed with a fuel burnup of 60 GWd/MTHM to determine when each burnable poison fuel type would decrease below a k_∞ of 1. For determining the plutonium material attractiveness in each burnable poison fuel type, the plutonium isotopic content of the used fuel was evaluated using Bathke's Figure of Merit formula. For the waste management analysis, the thermal output of each burnable poison fuel type was determined through ORIGEN decay simulations at 100 and 300 years after being discharged from the core. The performance of all six burnable poisons varied over the three criteria considered and no single burnable poison performed best in all three considerations.

• KIEAE Journal
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• v.8 no.6
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• pp.3-10
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• 2008

Since fire was founded in the world, human races have invented various heating methods. Ondol is traditional heating method in Korea. It is very the important work to trace the history and characteristics of Ondol which originated and was developed in the Korean peninsula. Especially, the study on Ondol will contribute to improving the present heating methods and predicting future ones. In this paper, we shall study through the analysis of documents such as oriental documents, the document of Choseon dynasty, European documents and American documents. In order to discover the origins of Ondol as one of the excellent heating method all over the world, This study aims at identifying the history and characteristics of Ondol in the Korean peninsula, through document analysis. Results of this study are as follows. 1) The first document about Ondol is Sookyongjoo(水經注), Chinese ancient geography book. Contents recorded in the book include the description related to Ondol at Kwankyesa temple which was located at the border land between Gogooryo(ancient Korea) and the northeast of China. 2) Ondol was popular heating method in Gogooryo(ancient Korea) and it was used in not only Gogooryo but also Silla Kingdom and Beakje Kingdom. Thereafter, it was also used widely in Goryo dynasty and Choseon dynasty. Thereby we know that Ondol has been used as a heating method for a long time in the Korean peninsula. 3) Ondol was covered with a floor paper since the beginning of Choseon dynasty. the paper made room clean and impacted on Korean life style. Because the floor was clean and warm, Koreans thus took off shoes and sat on the floor. 4) Ondol was spreaded to Jeju island in Korea before 16th century but wasn't used widely there. The reason was that Ondol was rare high class heating system and the weather was warm in Jeju island. 5) The overspreading of Ondol caused that poor people built roughly Ondol in the last of Choseon dynasty. So, the quality of Ondol gradually became lower and lower. 6) A westerner was impressed by the novelty of Ondol and Frank Lloyd Wright had played an important role to update and spread Ondol widely all over the world. Hailing Ondol as the ideal heating system, Frank Lloyd Wright began incorporating it in his buildings back in the U.S. and even invented a modified ondol system, using hot water running through pipes instead of the hot exhaust through flues.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.656-663
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• 2020

The study analyzed how F. L. Wright's architectural design concept changed based on Taliesin West (1940). According to the analysis, F. L. Wright was also influenced by the ancient Mayan civilization in addition to the Froebel block and Japanese culture. Wright realized the design style of Mayan civilization directly at the Biltmore Hotel, which is located near Taliesin West. Later, Wright's architectural design elements changed considerably. In particular, the local characteristics of Arizona, where Taliesin West is located, desert climate, and Cherokee Red, the color of ocatilla cactus growing in the desert, have been applied in his symbolic colors of his architecture. The following is a summary of the changed design concepts compared to before 1940: 1) A square module was used for floor plans before 1940 that later changed to a design concept called a circle and spiral. 2) The form of a column that simply emphasized its verticality changed to various shapes. 3) The gable roofs used in the early days of Wright's architecture changed to various forms that rose into the sky after 1940. This change was seen as the culmination of potential experiences that had not been realized before 1940.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.77-91
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• 1981

This study has been carried out for the publication of colored illustrations of Korean fungi. The fresh higher fungi were collected and photographed, for the most part, at Gwangneung, Kyonggi Province, Mt. Yongmun in Kyonggi Province, Mt. Sokri in Chungcheong Province, Mt. Jiyee in Kyeongsang Province, Mt. Mudeug in Jeonra Province, and Mt. Hanra in Jeuju Island from September 1, 1980 to August 31, 1981. These higher fungi were made colored slides and dried specimens, then classified. According to the investigated result, colored slides and classification for the common 151 species were completed among 620 spp. which were known all of the fungi in Korea. They were included 2 classes, 37 families, 89 genera, 149 species, 1 variety and 1 forma. Their world distributions were investigated. Fifteen species of them, that is, Aleuria aurantia (Fr.) Fuckel, Patella scutellata (St. Amans) Lambotte, Calocora viscosa Fr., Hygrocybe turunda (Fr.) Karst, Suillus pictus (Peck) Smith et Thiers, Marasmius purpureostriatus Hongo, Pleurocybella porrigens (Fr.) Sing., Lepiota bresadoiae Schulzer, Russula aurata Fr., Lactarius hygrophoroides Berk. et Br., Thelephora multipartita Fr., Inonotus mikadoi (Lloyd) Imaz, Antrodia mollis (Sommerf.) Karst, Ganoderma neo-japonicum Imaz. and Tyromyces lacteus (Fr.) Murr. were found to be new in Korea. In addition their common names and descriptons were prepared. According to study plan, this paper pressed only one page in colored plate among 151 species.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.102-112
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• 2010

By understanding physiological characters of plants and the environment, plant design should decide the relationship with other plants from the designer's curiosity of the plant's color, texture, form and other aspects. There are a traditional tendency that many designers put the plant's color ahead of other aspects. This study explores 4 gardens of Gertrude Jekyll's Munstead Wood, Vita Sackvill-West's Sissinghurst, Christopher Lloyd's Grest Dixter and Lawrence Johnston's Hidcote Manner. The flower border of Munstead is started with light grey and blue at the edge and it gets stronger colors like red and orange as the line comes to the middle. It is noticeable that white an blue colors were used unlike before. Sissinghurst made use of purple color which was very seldom used before and Dixter added orange to magenta color that was already there, giving a strong visual effect and through juxtaposition it could realize the wanted effect. A strong red border line was created in Hidcote Manner. Above mentioned designers arranged various colors so that visitors can experience different spacial senses according to observer's direction. In the cognitive space the main color and the secondary color arranged leading to the fact that the observer recognizes it as a whole. In plant design time means seasonal performance which influences the main color arrangement like gradation or contrast. Moreover, space determines the color's zone when it comes to plant design.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.19-30
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• 2012

For digital data compression, the quantization is the main part of the lossy source coding. In order to improve the performance of quantization, the vector quantizer(VQ) can be employed. The encoding complexity, however, exponentially increases as the vector dimension or bit rate gets large. Much research has been conducted to alleviate such problems of VQ. Especially for high bit rates, a constrained VQ, which is called the sample-adaptive product quantizer(SAPQ), has been proposed for reducing the hugh encoding complexity of regular VQs. SAPQ has very similar structure as to the product VQ(PQ). However, the quantizer performance can be better than the PQ case. Further, the encoding complexity and the memory requirement for the codebooks are lower than the regular full-search VQ case. Among SAPQs, 1-SAPQ has a simple quantizer structure, where each product codebook is symmetric with respect to the diagonal line in the underlying vector space. It is known that 1-SAPQ shows a good performance for i.i.d. sources. In this paper, a study on designing 1-SAPQ for the first-order Markov process. For an efficient design of 1-SAPQ, an algorithm for the initial codebook is proposed, and through the numerical analysis it is shown that 1-SAPQ shows better quantizer distortion than the VQ case, of which encoding complexity is similar to that of 1-SAPQ, and shows distortions, which are close to that of the DPCM(differential pulse coded modulation) scheme with the Lloyd-Max quantizer.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.401-411
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• 1989

The embryos of Pinus taeda, P. rigida, and P. taeda ${\times}$ rigida were cultured for adventitious shoot regeneration in vitro. Culture media were modified from Gresshoff and Doy (MGD), Murashige and Skoog (MMS), Lloyd and McCown (MLM), and Schenk and Hildebrandt (MSH). NAA was added to initiation media at a concentration of 0.1 or 0.01 mg/l. BAP was used at the concentrations of 0.1. 0.5, 1, 2, or 5mg/l. Each explant was induced for 3-4 weeks on solid medium. All explants were cultured up to 16 weeks. Illumination was about $1506{\pm}540lux$ at the level of the tissues in the growth room with a temperature of $25{\pm}2^{\circ}C$. A 16-hour photoperiod per 24 hours was used. Half-strength medium was used for all the subcultures. For shoot production by loblolly pine, MMS, MLM, or MSH is preferred with 5 mg/l BAP with either 0.1 or 0.01 mg/l NAA. For shoot production by pitch pine, MMS, MLM, or MSH is recommended with 2 or 5 mg/l BAP with 0.1 mg/l NAA. For shoot production by the hybrid pine, MMS or MLM is more effective with 1, 2 or 5 mg/l BAP with 0.1 mg/l NAA. There were no differences recognized among the species tried in the patterns of bud formation and shoot development. Different composition of media, in major and minor salts or possibly in vitamins, should be tested for the two developmental stages of adventitious shoots ; the induction of shoot buds and the elongation of them into shoots.