• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.189-189
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• 2008

Due to the environmental issue vast research is going on to replace the widely used lead contented piezoelectric materials. Bismuth sodium titanate (abbreviated as BNT) based bismuth sodium titanate-barium titanate (abbreviated as BNBT) ceramic was prepared by using modified method rather than conventional mixed oxide method. This modification was made to improve the properties of BNT based ceramic. In this procedure $BaTiO_3$ (abbreviated as BT) was prepared using conventional mixed oxide method. Analytical grade raw materials of $BaCO_3$ and $TiO_2$ were weighted and ball milled using ethanol medium. The mixed slurry was dried and sieved under 80 mesh. Then the powder was calcined at $1100^{\circ}C$ for 2 hours. This calcined BT powder was used in the preparation of BNBT. Stoichiometric amount of $Bi_2O_3$, $Na_2CO_3$, $TiO_2$ and BT were weighted and mixed by using ball mill. The used calcination temperature was $850^{\circ}C$ for 2 hours. Calcined powder was taken for another milling step. BNBT disks were pressed to 15 mm of diameter and then cold isostatical press (CIP) was used. Pressed samples were sintered at $1150^{\circ}C$ for 2 hours. The SEM microstructure analysis revealed that the grain shape of the sintered ceramic was polyhedral and grain boundary was well matched where as the sample prepared by conventional method showed irregular arrangement and grain boundary not well matched. And sintered density was better (5.78 g/cc) for the modified method. It was strongly observed that the properties of BNBT ceramic near MPB composition was found to be improved by the modified method compare to the conventional mixed oxide method. The piezoelectric constant dB of 177.33 pC/N, electromechanical coupling factor $k_p$ of 33.4%, dielectric constant $K_{33}^T$ of 688.237 and mechanical quality factor $Q_m$ of 109.37 was found.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.340-343
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• 2008

A new pale yellow gerbera(Gerbera hybrida Hort.) cultivar 'Honey Cream' was developed from a cross between 'Princessa' and 'Picasso', followed by seedling and line selections at the Flower Research Institute, Gyeongnam Agricultural Research and Extension Services(ARES) in 2006. Three times evaluations were conducted from 2003 for the detailed characteristics of the new cultivar. 'Honey Cream' has semi-double type large flowers in good harmony with pale yellow(RHS, 11-D) ray floret and green center. It has good, stable flower shape and strong peduncle, and its vase life was 12.3 days. The average flower yield of 'Honey Cream' was about 48.5 stems per plant/year in greenhouse trails during 2003 and 2006. This cultivar was registered to the Korea Seed and Variety Service(KSVS) for commercialization in 2007. Year-round production of this cultivar is possible in the greenhouse condition in Korean climate.

• Journal of Sericultural and Entomological Science
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• v.18 no.2
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• pp.65-78
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• 1976

The mulberry small weevil, Baris deplanata ROELOFS, has highly infested mulberry trees in Korea. As the damage caused by the mulberry small weevil in mulberry fields has been increased over the country since 1969, the authors has carried out a series of biological and controlling studies on the pest from 1971 to 1972. The results obtained are summarized as follows. 1. The adult weevil is elongate oval in shape with black in color and the probocis is long as usual in curculionidae. The size of adult female is 3.30${\pm}$0.04mm in length, 1.47${\pm}$0.04mm in width, and the length of proboscis is 1.25${\pm}$0.014mm, while adult male is 3.28${\pm}$0.06mm in length, 1.40${\pm}$0.04mm in width, and the length of proboscis is 1.30${\pm}$0.02mm. The antenna is geniculate consisting of 12 segments. The terminal sternite of the abdomen has a pointed tip in male but not in female. 2. The egg is long oval in shape, milky white in color, 0.51${\pm}$0.05mm in length and 0.32${\pm}$0.02mm in width. 3. The mature larva is cylindrical and light yellowow in color except the head of dark brown, and legless, 3.88${\pm}$0.06mm in length, 1.40${\pm}$0.02mm width, each segment bearing many wrinkless and short setae. 4. The pupa is long oval, milky white and exarate, 3.53${\pm}$0.09 in length, 1.40${\pm}$0.03mm in width. 5. Majority of the species has one generation through a year and overwinters as adult in xylem of withered branch and come out again from late April to early May in next year. But some of the female oviposit in the same year and the offsprings overwinter as larva (0.4%) or pupa (0.1%) 6. The eggs are mostly laid under the cork layer of withered branch and the number of eggs deposited by an adult female is 73.44${\pm}$8.74, the average egg-laying period is 33.88${\pm}$6.04 days. The incubation period is 11.69${\pm}$0.39 days, the larval period 45.04${\pm}$1.63 and the pupal period 11.05${\pm}$0.49 days. The period of adult's activity is 46.7${\pm}$5.90 days. 7. The larvae feed on the cambium under the bark and adults feed on the winter bud, the latent bud, the leaf stalk and the base of newly shoot. 8. An active period of adults was observed during the period of 4 months from April to July. However, the peak of adult-density occurred in the early May (in the fields of spring-prunning) and early to middle June(in the fields of summer-prunning). 9. There is a positive correlation between the density of larvae and diameter and length of the branches. 10. The pattern of distributions of the adult of mulberry small weevil is negative binomial distribution. 11. The chalcid fly was disclosed to be a natural enemy which was parasite on the larvae of mulberry small weevil and its parasitic ratio was 11.9%. 12. Phosvel D, Malix D, Salithion EC, DDVP EC, and Phosvel EC were effective for the control of adults and Satchukoto-S EC, and Salithio EC were effective for the control of larvae.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.353-366
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• 1992

This study was devised to purify the compound from tuna that have cytotoxic activities against various cancer cell lines and to observe its immunopotentiating activities. The cytotoxic compound was partially purified 277 fold, from petroleum ehter extract (crude extract) of tuna by silicic acid column chromatography (fraction D) and thin layer chromatography (Spot I). Cytotoxic activity was monitored using human colon cancer cell, HCT-48. The active compound (Spot I) was composed of seven materials which are fatty acids of four kinds ($C_{14:0},\;C_{16:0},\;C_{17:1},\;and\;C_{18:0}$) and unknown three fat materials. The active compound has cytotoxic activities against various cancer cell lines, that is, murine leukemic lymphocytes (L1210, P388) and human rectal (HRT-18) and colon cancer cells (HCT-48, HT-29). The patterns of size distribution of HCT-48 cells in the medium containing tuna extract were shifted to direction of the small size region. Also, the microscopic shape of HCT-48 cells were shrinked and distracted. The number of plaque forming cell and immunoglobin fraction of serum protein obtained from tuna-treated mice were increased, but natural killer cell activity was not affected.

• Korean Institute of Interior Design Journal
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• no.40
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• pp.34-41
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• 2003

A purpose of this study is to comprehend a concept of 'Open Space', realization of a deconstruction, presented in his works, based on a deconstruction and surrealism Coop Himmelblau's philosophical contemplation and to look into how this concept is interpreted in spaces. A concept of 'Open Space' is functioned as not a singular meaning but a multiple meaning accompanied with other formative ingredient and contemplation, scientific paradigm and a realation with a surroundings. The concept of 'Open Space' in their architentural space is applied. First, the space openness that represents to the extreme a concept 'Open Space', as a 3D designing ways that demolishes a structure and outgrows an ex siting thinking pattern, represents multiple grade spaces and an anti-gravity space. In a material, using glass and iron provides a spacial transparency and through this, visibly liberal sense that an interior and exterior is felt as an unification. Second, an non-expressive box pattern repulses to a spatial rank nature, outgrowing an uniform geometrical system, through demolishing a geometrical system, an edge and fold pattern. This is, as an anti-gravity, dynamic a typical structure, outgrowing an orthogonal system, interpreted as a composite meaning without division in spatial area. Third, the collage is used to represent a complexity and pluralism in representing 'Open space'. The collage that forms a image through combining a fragmentary elements into being a space change, composite constitution and spatial amusement. Thus, It is worthwhile to study how the collage that forms a diverse shape will be developed making what impact as an age and surroundings changed. As we contemplate in former part, Coop Himmelblou has deployed 'deconstruction beyond deconstruction' realm as just their midterm concept in their works like the words 'The architecture must climb', the deconstructive architect. A studying for their works reflecting the 'Open Space' concept based on deconstruction must be lasted and this enables us to comprehend space concept containing an architecture and interior design.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.1 s.26
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• pp.37-43
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• 1988

The purpose of this study is to compare Jegory with Simii, and to understand the construction of Jegory, assuming that Jegory is related to Simii system. The results obtained are as follows ; 1. Teie-ku-li was the first record among the name of Jegory in literature, was called about A.D. 1408. 2, When Jegory and Simii were cut, front-back width and sleeve length standarded on the width of cloth. 3. The cutting of Jegory disposed to seperate right and left width, to connect front and back width up to the middle term of Chosen Dynasty Period. 4. The sewing order of the Simii was Dungsol-Jindong-Baerae-Sougu. The sewing order of the Jegory in $\ulcorner$ The Book of Chosen sewing$\lrcorner$ was Shoulder-Jindong-Baerae-Sup-Dungsol-Kit and in literature of 1960's it was similar to Simii. 5. The lined clothes in $\ulcorner$The Book of Chosen Sewing$\lrcorner$ was sewn to put the inside in the surface, different from the literature of 1960's. 6. In Chosen Dynasty Period the shape of Simii depended on $\ulcorner$Moon Kong Ka Rye$\lrcorner$, but it was changed to similar to Jegory in the latter term. 7. The empty void in Jegory offers usefulness. It relates to Oriental negativism that yin is more useful than yang.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.2
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• pp.11-18
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• 2016

This study focused on examining the possibility for recycling of Fe-Si electric sheet. We manufactured Fe-6.5Si mother alloy using by Fe-Si electric sheet scrap for transformer core materials. And then, soft magnetic alloy powder which diameter and shape were $45{\sim}150{\mu}m$ and sphere type was prepared by gas atomization process. As we compared to commercial Fe-6.5Si powder, its diameter distribution and microstructure of recycled powder was a similar. To investigate the possibility of reusing the soft magnetic composite sheet for electronics, recycled powder was treated to have a high aspect ratio (AR), and we finally obtained the 65~66 AR and $2.3{\mu}m$ thickness powder. To release the residual stress of powder, heat treatment was conducted under $300{\sim}400^{\circ}C$, $N_2$ gas. And then, soft magnetic sheet was made by tape casting process using by those powders. After the density and permeability of tape was measured, and we confirmed that the recycled Fe-Si electric sheet scrap was possible to reuse the soft magnetic materials of electronics.

• Fashion & Textile Research Journal
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• v.16 no.6
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• pp.1001-1007
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• 2014

We surveyed the wearing characteristics of hip protectors. The problems of existing hip protectors were identified and the directions for improvement were presented. The evaluation of wearing characteristics was conducted on the 100 elderly women (60 to 85 years) with 5 types of hip protector. The questionnaire was composed of history and characteristics on falling, hip protector acceptance, preference, use characteristics and improvement requirements. The result of wearing characteristic evaluation indicated that 52% of the subject experienced falling in winter. Incidents resulting from falling occurred: outdoors (74.5%), bathroom (10.9%), and kitchen (5.5%). Body parts to be protected were in several areas: 35.6% for lumbar, 26.9% for hip joint, and 15% for hip bone. Participants prefer a belt B type design at a rate of 56.9% because it provided a sense of stability by clinging to the body and upholding the waist. Belt B type was the most appropriate in terms of fit, allowance, mobility, and design except pad thickness. To reduce the risk of hip fracture, hip protector needs to be designed in consideration of user's type of fall and body shape. The pattern and size of a hip protector has to be improved in regards to the amount of discomfort. An objective evaluation is needed for the ergonomic design of a hip protector based on and analysis of 3D body image of the elderly and the shock-absorbing quality of pad.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.5
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• pp.35-47
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• 2011

Dynamic characteristics of a flow control valve, which plays an important role in thrust and O/F control of liquid rocket engines, have been analyzed by the AMESim simulator modeling. The speed control method was proposed for the control of the flow valve equipped with a BLDC motor. The experimental results demonstrated the feasibility of systematical application as well as the performance of the speed control method. Moreover, the speed control method for BLDC motor is much simpler than the P control method in complex flow systems. With the speed control method, the control flow characteristics were evaluated according to plunger shapes. Consequently, same plunger shape proved to be more efficient in the mixture ratio control operated by two flow valves. It was also shown that the appropriate modification of plunger shapes could reduce the mixture ratio perturbation by 0.5%.

• Journal of Ocean Engineering and Technology
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• v.28 no.5
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• pp.440-451
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• 2014

A multi-static SONAR system consists of the transmitters and receivers separately in space. The active target echoes are received along the transmitter-target-receiver path and depend on the shape and aspect angle of the submerged objects at each receiver. Thus, the target echo algorithm used with a mono-static system, in which the transmitter and receiver are located at the same position, has limits in simulating the target echoes for a multi-static SONAR system. In this paper, a target echo modeling procedure for a 3D submerged object in space is described based on the Kirchhoff approximation, and the SONAR system is extended to a multi-static SONAR system. The scattered field from external structures is calculated on the visible surfaces, which is determined based on the locations of the transmitter and receiver. A series of experiments in an acoustic water tank was conducted to measure the target echoes from scaled targets with a single transmitter and 16 receivers. Finally, the numerical results were compared with experimental results and shown to be useful for simulating the target echoes/target strength in a multi-static SONAR system.