• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.31-38
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• 2015

In order to achieve a high speed and high quality silicon wafer bonding, the room-temperature direct bonding using atmospheric pressure plasma and sprayed water vapor was developed. Effects of different plasma fabrication parameters, such as flow rate of $N_2$ gas, flow rate of CDA (clear dry air), gap between the plasma head and wafer surface, and plasma applied voltage, on plasma activation were investigated using the measurements of the contact angle. Influences of the annealing temperature and the annealing time on bonding strength were also investigated. The bonding strength of the bonded wafers was measured using a crack opening method. The optimized condition for the highest bonding strength was an annealing temperature of $400^{\circ}C$ and an annealing time of 2 hours. For the plasma activation conditions, the highest bonding strength was achieved at the plasma scan speed of 30 mm/sec and the number of plasma treatment of 4 times. After optimization of the plasma activation conditions and annealing conditions, the direct bonding of the silicon wafers was performed. The infrared transmission image and the cross sectional image of bonded interface indicated that there is no void and defects on the bonded wafers. The bonded wafer exhibited a bonding strength of average $2.3J/m^2$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.127-134
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• 2018

This study evaluated the effects of high air temperature and waterlogging duration on growth and yield of Kimchi cabbage. Air temperature treatments were applied with ventilation; optimal (set $20^{\circ}C$) and delayed ($30^{\circ}C$) in the greenhouses. The waterlogging treatment levels were implicated 0, 12, 24, 48, and 72 hours, respectively. The growth of Kimchi cabbage was significantly affected by waterlogging duration. The head weight decreased by combining severe waterlogging and high air temperature. Net photosynthetic rate under the combination of non-waterlogging and optimal air temperature was $22.6{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, which was the greatest, while that of 72 hours-waterlogging was rapidly decreased. The percentage of formality with 0, 12, and 24 hours-waterlogging was over 88%, however, those of 72 hours-waterlogging with optimal and delayed ventilation were 64 and 68%, respectively, which were dramatically reduced. The yields were more affected by waterlogging duration than air temperature treatment because of deducting as increased waterlogging periods. These results indicate that waterlogging treatment reduced the yield and quality of Kimchi cabbage, thus it will be feasible to enhance the harvest time when severe waterlogging in the field.

• Analytical Science and Technology
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• v.14 no.2
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• pp.131-139
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• 2001

There is personal difference in the concentrations of trace elements in human hair according to human life or history suck as occupation, race, sex, age, food habit, social condition and so on. It is also found that the individual's deviation of elemental concentrations is reflecting the degree of environmental pollutants exposure to human body, intakes of food and metabolism. To compare the degree of accumulation in the hair tissue, human hair samples were collected from five positions of head and analyzed by non-destructive neutron activation analysis with and without washing according to IAEA's recommended method. Analytical quality control is performed using the certified reference material. The relative error of Cu, Cr, Na, Co, Mg, As, Se, Zn and those of Mn, Ca, Fe, Sr are within ${\pm}5%$ and ${\pm}10%$, respectively and the relative standard deviation of elements are within ${\pm}10%$. The deviations between the individuals and hair sampling positions were estimated. The deviation of individual was seven times more than that of positions. Under the defined condition, the difference and the correlation of elemental concentrations were compared with two different groups, office and factory workers. The result can be used as a fundamental data for human health and environment assessment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1347-1355
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• 2015

In this study, the physicochemical properties, antioxidant capacities, and volatile flavor compounds of oriental melon wine prepared by freeze concentration after heat treatment (HA), ascorbic acid treatment (AAT), and heat and ascorbic acid treatment (HAAT) were investigated. During fermentation period, the melon wine by HAAT showed greater reduction of soluble solids and reducing sugar contents compared to other treatments. In addition, the melon wine treated with HAAT also showed a higher L value and lower browning index compared to other treatments. After aging, free sugar including fructose, and organic acids including citric acid, succinic acid, and malic acid were detected in all samples. For antioxidant activities and contents, HAAT treated wine showed greater antioxidant activities and total phenolic contents than those of others. In GC/MS analysis, a total of 33 volatile flavor compounds were identified. In the principal component analysis of volatile flavor compounds, principal components 1 and 2 represented 88.15% of the whole date distribution and showed opposite tendencies. Taken together, HAAT enhanced the antioxidant activities and sensory properties of oriental melon wine. Moreover, freeze concentration gave the different volatile flavor characteristics in oriental melon wine.

• Progress in Medical Physics
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• v.14 no.1
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• pp.8-14
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• 2003

The spinal cord dose is the one of the limiting factor for the radiation treatment of the head ＆ neck or the thorax region. It is not an easy task to maintain the spinal cord dose below tolerance and to keep the clinically acceptable dose to the PTV in this region. To overcome this problem, the spinal cord partial block technique (PBT) with the dynamic Multi-Leaf Collimator (dMLC) has been developed. This technique is an extension of the conventional treatment planning. In the beginning the beam directions are selected as same as the conventional treatment planning to encompass the PTV, then the partial block are designed to shield the spinal cord. The plan comparisons between the conventional therapy plan and the PTB plan were performed to evaluate the validity of this technique. The mean dose and the dose volume histogram (DVH) were used as the plan comparison indices. A series of quality assurance (QA) was performed to guarantee the reliable treatment. The QA consisted of the film dosimetry for the verification of the dose distribution and the point measurements. The PBT plan generated better results than the conventional treatment plan and it was proved to be useful for the H＆N region.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.84-91
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• 2006

This study was carried out to comparatively evaluate growth characteristics of rice cultivars under rice-mono (conventional) and rice-Chinese milk vetch (Vetch) cropping system. Six rice cultivars such as Geumobyeo, Pungmibyeo, Hwayeongbyeo, Sobibyeo, Junambyeo and Dongjinbyeo were tested in 2005. The results obtained are summarized as follows ; plant height and culm length of all the tested cultivars at heading and harvest time were shorter in rice-vetch cropping system than conventional, however, nitrogen content of rice plants at heading and harvesting time was higher in rice-vetch cropping system. The total amount of nitrogen of rice plants was higher in conventional than rice-vetch cropping system. Nitrogen content of rice plant and uptake of Pungmibyeo was the highest of all the tested cultivars in both cropping systems. Generally, grain yietd ef tested cultivars seemed to be higher in conventional than rice-vetch cropping system. And it was the highest in Junambyeo as compared to those of other cultivars. Head rice ratio and protein content were higher in rice-vetch cropping system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.379-385
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• 2006

This experiment was carried out to investigate the optimum planting density in low fertilizing cultivation of machine transplanting in rice field of Honam Agricultural Research Institute, NICS for $2004{\sim}2005$. Sobibyeo which belongs to medium maturing variety and Nampyeongbyeo which belongs to medium-late maturing variety were transplanted on May 30. In this experiment, there was no significant difference in heading date between planting density and nitrogen fertilization rate, and heading dates were August 8 in Sobibyeo, and August 14 in Nampyeongbyeo respectively. In relation to lodging character, lodging Index was high where the nitrogen fertilization rate and planting density were high. As planting density increases, panicle number per $m^{2}$ increased irrespective of nitrogen fertilization rate. When nitrogen was 6 kg/10a, rice yield of Sobibyeo was more where planting density was 90 hill per $3.3m^{2}$, and that of Nampyeongbyeo was more where planting density was 80 hill per $3.3m^{2}$. When nitrogen was 9 kg/10a, rice yield of Sobibyeo was more where planting density was 100 hill per $3.3m^{2}$, and that of Nampyeongbyeo was more where planting density was 110 hill per $3.3m^{2}$. Head rice rate of brown rice was higher when planting density increased, and was higher at 6 kg/10a nitrogen rate than 9 kg/10a nitrogen rate in all varieties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.3
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• pp.235-243
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• 1985

A survey of 113 children, aged 4 to 6 years, of the San Cheon a day care center, located in the upland, over populated, poor area of Seoul City, was conducted from July 28 to September 6, 1982, to investigate the dietary and nutritional status, and prevalence of parasitic inpection. House size was 10.1 Pyung; number of households per house, 3.1; number of family member per household, 4.8; and number of family members living together per room, 3.7; on the average. Only 49% of households possess own houses and the others live in the rented houses. About 40% of mothers were engaged income-producing activities within or outside of the home. Mean values of height, weight, arm circumference, girth of chest, and girth of head ranged from 98.4 to 102.2% of KIST mean. However, 13% of the subjects were assessed as undernutrition for 'weight for height'. Mean value of hemoglobin was $12.9{\pm}2.9\;g/dl$ and mean hematocrit value was $35.2{\pm}5.5%$; 17.9% of the subjects were proven to be anemic according to the criteria of the WHO. The positive prevalence of parasitic inpection was 3.3%, significantly lower than that observed in any other area, probably because of community parasitic control project. Intakes of energy and nutrients except thiamin and ascorbic acid were far below RDAs. Carbohydrates for energy provided 71. 2 to 73.8% of total energy intake; protein accounted 11.3 to 12.2%; fat provided 14.5 to 16.6%. Energy intake was divided among breakfast, lunch, evening meal and snack, on the average, in a percentage of 22.0; 23.4; 24.4; 30.2. There was significant correlation between pattern of food consumption and nutrient intakes. The nutrient intakes and quality of foods were highly correlated to the maternal factors, especially mother's educational level. The study suggested that development of nutrition guides for mother and children would be needed to improve nutritional status of those young children.

• Journal of the Korea Computer Industry Society
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• v.5 no.9
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• pp.1101-1110
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• 2004

In the first quarter of 2004, there were about 1 billion 348 million mobile phone users worldwide with a penetration rate of only 29%. Korea ranks among the highest in the use of mobile communication, having over 36 million mobile phone subscribers with a mobile phone penetration rate of 75% as of May 2004. Since the introduction of wireless Internet service in May 1999, the number of subscribers rose to 34.5 million with 95.3% of the total mobile phone subscribers using wireless Internet services in May 2004, largely due to continued investments by telecommunication service providers, improvement of mobile handsets (color and digital camera phones) and implementation of policies on mobile number portability. In the Korean wireless Internet market, there are many user complaints since the service providers are competing with each other through TV commercial sales and phone discounts rather than improving their call quality, services and billing systems. therefore there is a growing need to improve the billing systems through means such as the implementation of reasonable payment plans according to consumer use, development of a wireless Internet billing system that can predict the number of users and establishment of pricing standards for controlled data (head, tail, etc...) as well as menu information by testing the texts. multimedia, video and other types of content provided by the three major mobile communication companies. The purpose of this study is to promote wireless Internet services and protect user rights by proposing a reasonable way to improve the billing systems for wireless Internet services after conducting a comparative analysis of file size and billing data of each of the service providers through a verification test on a packet billing system for wireless Internet services.

• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.35-45
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• 1996

After transplantation of groin free flap was sucessed by the Daniel and Taylor in 1973, the reconstruction of plastic surgery was extensive and universal due to rapidly developement of anatomic study of the donor site and technique of microvascular surgery. The free tissue transfers is possible to be early activity and rehabilitation by one stage operation. It currently available allow transfer of specific tissue quality as bone, muscle, nerve to achieve a functional and cosmetic result as well as the most favorable secondary defect. But free flaps require critical, skillful technique and lengthy operating time. Also it has disadvantage of donor site morbity at the large tissue transfer. Authors were transferred with 107 cases in 103 patients from May 1987 to June 1996, and then we analysed free tissue transfer to acquire more increased sucess rate, satisfactory functional and cosmetic results. The sexual distribution was male prominent in 79 cases(76.7%), female in 24(23.3%) and age was variable distribution from 3 to 76 years old. The cause of defects was most prevalent in trauma of traffic and industrial accident in 51 cases(49%). The common recipient site were lower extremities in 47 cases(43.9%), upper extremities in 28 cases(26.5%), head and neck in 25 cases(23.4%), and trunk in 7 cases(6.5%). The type of transfer were free skin flaps in 46 cases(43%), free muscle or musculocutaneous flaps in 31 cases(29%), free vasculized or osteocutaneous flaps in 10 cases(9.3%), and specilized free flaps in 20 cases(18.7%). The anastomosis of artery was end to end anastomosis in 94 cases(87.9%), end to side anastomosis in 13 cases(12.1%) and all vein was end to end anastomosis. The number of anastomosed vessels were one artery one vein in 62 cases(57.9%), one artery two vein in 45 cases(42.1%) and vein graft was performed only one case. The postoperative mornitoring were used with temperature, color of flap, capillary refilling time, ultrasonogram, bone scan, doppler, and endoscopy. The reexploration was performed in 9 cases(8.4%), and then flap was loss in 3 cases(2.8%). Accordingly overall success rate was 97.2%. The postoperative complication was early vascular occlusion, hematoma, partial necrosis and late bulkiness, scarring, color dismatch etc. Therefore, free tissue transfer is the preferred method of treatment, even through conventional local and distant flaps are available.