• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3080-3086
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• 2009

We have analyzed the output characteristics of a LGP with pyramid shaped pattern by using a 3-D simulation tool. The influences on the LGP output of various parameters such as the pattern shape, pattern occupation ratio, pattern size, and etching angle were investigated. Comparing the pyramid shaped pattern with hemispherical patterns, little difference was observed. And, it was proved that the pattern occupation ratio and etching angle have relatively large effects on LGP output characteristics, while the pattern size has no effect. Therefore, we can improve the LGP characteristics by optimizing pattern structure and distribution.

• Journal of Korean Society of Water and Wastewater
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• v.8 no.2
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• pp.1-11
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• 1994

This study was conducted to develop a new RBC process available for the effective removal of organic matters and nitrogen in sewage. The RBC process for the oxidation organic compounds and nitrification was designed to occur at the 1st-stage and next-stage RBC respectively. Then nitrified water was recycled to the denitrifying RBC located at the lower part of the 1st-stage RBC. Some results were summarized as follows. 1. The loading limitation was represented as $60g{\cdot}COD/gm^2/day$ in experiment of simultaneous removal of organic matter and nitrogen. The maxmum COD % removal was 85% at the load $35g{\cdot}COD/m^2/day$. 2. The $NO_3-N$ % removal was approximately 80% at the load $60g{\cdot}COD/m^2/day$ and the maximum $NO_3-N$ remaval rate was $3.9g{\cdot}COD/m^2/day$ and the overall C/N ratio of 11.0 as required to achive 80% of $NO_3-N$% removal. 3.$NO_3-N$ removal rate was rapidly decreased above the load $7g{\cdot}NH_4{^+}-N/m^2/day$ and the maximum $NO_3-N$ removal rate was $3.7g{\cdot}NO_3-N/m^2/day$. 4. Irrespective of the recycle ratio, the COD % removal at the system of 2-stage RBC unit was nearly constant as 89% while the maximum one in the 1st-stage unit was 77% in the case of 50% recycle. 5. The maximum COD % removal in the 3-stage RBC system was 93% while 1st-stage one being 80%, under the $NH_4{^+}-N$ load of $7.4g/m^2{\cdot}d$. Also maximum percentage of nitrification and denitrification was 69% and 41% respectively, under the same $NH_4{^+}-N$ load.

• The Journal of Korean Academy of Prosthodontics
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• v.27 no.1
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• pp.83-102
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• 1989

This study was done to analyze the sound distortion, before and after insertion of the palatal palates. For this study, 4 healthy subjects (3 males and 1 female, each 24-year-old), who were born in Seoul were recruited from K university, and 3 type palatal plates were fabricated, each palatal thickness being 1.0mm, 2.5mm, dentoalveolar portion 2.5mm and elsewhere 1.0mm, named B,C,D-type repectively, and informants's sounds of /사(sa), 서(se), 소(so), 수(su), 스($s\.{+}$), 시(si)/ were recorded, without plate, and with palatal plates of different types, in succession. A series of analysis were adminstered through a 16 Bit IBM PC/AT using linear combination methods. These experiments were analyzed by the Cepstrum (Weighted and Euclidian), Log Area Ratio, Linear prediction correlation methods The findings led to the following conclusions : 1. It was confirmed that the same consonant, /ㅅ(s)/, variously distorted by the following vowel. 2. By and large, 시($s\.{+}$) was the most distorted in all conditions, and (sa), 소(so) were the least distorted in each condition. 3. There were no persistant correlation of the palatal plate types, and sound distortions of each informant were diverse with no regularities. 4. There were persistent correaltion to the Cepstrum (Weighted, Euclidian), Log Area Ratio. However, Linear prediction correlation has a different alteration pattern.

• The Korean Journal of Zoology
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• v.6 no.2
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• pp.21-27
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• 1963

This study is concerned with alterations in chromosomes (numbers and morphology) when the culture of Chinese hamster cells (FAF-28 strain) was treated by steroids, testosterone and DOC. 1. In 200 cells of normal untreated cells as control population the chromosome of stemline was decided as which was contained in 158 cells ; that is , in 79 percent of the population. The average chromosome number in above 20 cells observed was calculated as 23.95 with minimum limit at 20 and maximum limit at 70. 2. Many different chromosome numbers, ranging from 19 to 352 were observed in the 200 cells treated by testosterone. The diploid number of 22 showed the peak of variation curve was counted in 71 cells (35.5%) and an average chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome numbers in the 200 cells observed ranged from 20 to 181 , an average chromosome number was also found to be 30.09. 4. The chromosome component in the cultured normal FAF-28 cells with 22 diploid chromosomeswas as follows ; 9a) 2 paris were long and metacentric (LM), (b) 3 pairs were medium length and metacentric (MM), (c) 3 pairs were small and subtelocentric (SS) and (d) 3 pairs were small and metacentric (SM). 5. The twenty cells with 44 chromosomes were selected at random from each cell population treated with testosterone and DOC , so that chromosome idiogram and morphology could be studies. In the twenty cells of the testosterone treated population the average ratio of above four groups, LM ; MM;Ss:SM, was found to be 8.6 : 10.8:13.5:10.7. On the other hand, the average ratio in the same number of cells of the DOC treated one was 7.7 :11.4:12.5:12.7. 6. The five types of the altered chromosomes morphologically in the hundred cells selected at random from each cell population treated by testosterone and DOC were observed (Type I-V). The thirty-one altered chromosomes were found to be in the testosterone treated cell population and the sixteen in DOC treated.

• Journal of the Korean Home Economics Association
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• v.29 no.1
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• pp.51-58
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• 1991

This study was conducted to investigate the dietary and nutritional status supplied by group feeding for blue color and white color in Seoul and Kyunggi area. The results are summarized as follows : 1. Blue color and white color of the average food supply per person per day was 1370.0g. Blue color of the total fool supply was consisted of 35.1% grain, 44.1% vegetables. White color of the total fool supply was consisted of 31.8% grain, 44.0% vegetable. The amount of milk product, fruit and fat supply were very small. 2. Blue color and white color of the ratio of main dish and side dish supplied was 69 : 31, 60.0 : 39.7. 3. Main dish all is rice. Side dish ard kinds of soupes and Jigeai Johngol in the two groups. In the kind of side dish white color much more than blue color. Dessert are scarcely supplied in the two groups. 4. The mean daily supplies of energy and 9 nutrients were above the level of the R.D.A. Blue color and white color of the mean daily amount of energy supply was 2653.0㎉ 3022.6㎉. Blue color and white color of the ratio of carbohydrate, protein, and fat supplied was 68.4%, 18.6%, 13.1%, and 62.1%, 20.9%, 17.0%. 5. Blue color and white color of the average feeding cost amounts to 460won, 812won per meal. 6. Blue color; There were high correlations in supply amoung energy, protein, fat. Carbohydrate, calcium, iron, riboflavin, niacin. White color; There were high correlation in supply amoung energy, protein, carbohydrate, calcium, iron, thiamin, riboflavin, niacin, vit-C.

• Journal of the Korean Home Economics Association
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• v.26 no.4
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• pp.43-52
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• 1988

This study is intended to reveal the nutritional realities of school children due to their box lunch. The samples were chosen at random from the third grade to the sixth grade children in an elementary school in Seoul : 122 male and 111 female children, 233 children in all. among the subjects, 44.3% have a family of four, 34.3% have over 500,000 won of family income a month, and 44.3% of their mothers graduated from a high school. The average intake of calories is 573.6 Kcal, and the ratios of the calory intakes to the recommended amounts are 90.6% in the third grade children and from the fourth grade to the sixth grade, 79.5% in the male children and 82.9% in the female children. The average consumption of protein is 21.0g and the ratio of animal protein is 41.4%. the ratio of energy yield nutrients is 67.4% : 14.5 : 18.0 (carbohydrate : protein " fat). Considering the recommended amounts, the intake of protein is enough; the consumption of vit, A, thiamine, niacin are appropriate;and the intake of calories, Riboflabin and ascorbic acid, calcium, iron are deficient. Even though there is no significant difference between the socioeconomic factors (the standard of education of the subjects' mothers and family income0 and the intakes of calories and protein, there is a tendency that the consumption of protein intake si more abundant in the middle class than in any other class. The subjects' distribution of the physical growth index, is as follows; A (6.9%), B(19.3%), C(48.5%), D(13.7%) and E (11.6%). As the subjects' intake of calcium increases, the weight shows significant improvement (p<0.001). As the consumption of calories increases, the physical development shows significant improvement (p<0.05), and the weight shows significant increase (p<0.001).

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1269-1270
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• 2007

Carbon nanotubes (CNTs) are directly grown on W-tips at $700^{\circ}C$ using an ICP-CVD method. Sharpening of W-tip is done by electrochemical etch and their diameters are limited to range from $3{\mu}m$ to $5{\mu}m$. Catalysts for CNTs growth are formed by RF and DC co-sputtering systems using Ni and Co. The composition ratio of Ni and Co has been evaluated by energy dispersive x-ray spectroscopy (EDS). The micro-images of CNTs are monitored by field emission scanning electron microscope (FESEM). It is observed from Raman study that the intensity of the D-peak is increased by increasing the amount of Co catalyst. Furthermore, the measurement of field emission properties of CNTs show that the CNT grown on a single Co catalyst possess the greatest performance such as $V_{th}$=1,115V and $I_{max}=164{\mu}A$.

• Polymer(Korea)
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• v.32 no.6
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• pp.555-560
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• 2008

Polymer-modified mortars have been largely used as paving materials, flooring, waterproofing material, adhesives, anticorrosive linings, deck coverings, and other various materials. The various types and properties of the mixed polymer largely affect the characteristics of polymer-modified mortar that has been mixed with polymer latexes. Consequently, its application purposes are varied according to these properties. This paper investigates the typical properties of polymer-modified mortars that contain styrene and butyl acrylate latexes and styrene butadiene rubber. They are then tested to obtain air contents, water-cement ratios, flexural and compressive strengths, water absorption, and chloride-ion penetration. From the test results, the superior flexural strength of polymer-modified mortars is obtained at a S/BA-2 and a polymer-cement ratio of 20%. And, the water absorption and chloride ion penetration depth are greatly affected by the polymer-cement ratio rather than the types of polymer. In the polymer-modified mortar and concrete structures, aggregates are bound by such a co-matrix phase, resulting in the superior properties of polymer-modified mortar and concrete compared to conventional mortar and concrete.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.9-14
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• 2020

Left atrial enlargement (LAE) is an important diagnostic factor in dogs with myxomatous mitral valve disease (MMVD). It is associated with the onset of congestive heart failure (CHF). Recently, a new radiographic left atrial measurement called vertebral left atrial size (VLAS) was introduced. This can be considered as a left atrial enlargement above 2.3. It appears to be related to the severity of MMVD. However, serial changes in VLAS in relation to disease progression and improvement in patients have yet to be studied. This study aims to assess the value of VLAS as a left atrial size monitoring indicator by examining correlations with VHS, LA/Ao ratio and LVIDDN, and comparing serial changes in dogs. A total of 126 dogs were studied with their owners' consent. The dogs were classified into four MMVD groups (Control, B1, B2, C-D) following the ACVIM Guideline by performing a physical examination, radiography and echocardiography. Besides, 24 and 17 dogs were reevaluated to compare values in relation to the progression and improvement of MMVD. VLAS showed significant increase according to the progress of the MMVD stage. This was the same in the Maltese breed group. A strong positive correlation was found between LVIDDN, VHS, LA/Ao ratio, and VLAS. The results of this study found VLAS to be significantly different according to left atrium size, and there was a correlation between disease progression and VLAS levels in each dog. Therefore, VLAS may be used to detect changes in left atrium size as an additional monitoring index of MMVD.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.829-838
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• 2021

Purpose: The Air Spring Damper System (ASDS) is proposed when existing concrete structures that have not been seismic resistant for economic and technical reasons or low-rise concrete structures that are difficult to earthquake. Method: To conduct a study on the damping force antigen in the kinetic equation of free vibration, we analyze whether this device has damping ability as a damper experimentally and theoretically, and examine the possibility of field application. Result: The air damper system is considered to be more economical than steel hysteresis dampers even if the number of dampers increases due to its easy manufacture and construction and low restrictions on shape, size, material, etc. Conclusion: In an air spring damper system, it is essential to reduce the diameter of the air inlet/outlet hole to improve the damping ratio, and in this case, if the diameter exceeds a certain lower limit, consideration of the compressibility of air is required, so further research is needed.