• The KIPS Transactions:PartC
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• v.14C no.4
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• pp.349-358
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• 2007

Ethernet Passive Optical Network(EPON), which is one of PON technologies for realizing FTTx(Fiber-To-The-Curb/Home/Office), can cost-effectively construct optical access networks. In addition, EPON can provide high transmission rate up to 10Gbps and it is compatible with existing customer devices equipped with Ethernet card. To effectively control frame transmission from ONUs to OLT EPON can use Multi-Point Control Protocol(MPCP) with additional control functions in addition to Media Access Control(MAC) protocol function. For EPON, many researches on intra- and inter-ONU scheduling algorithms have been performed. Among the inter-ONU scheduling algorithms, IPS(Interleaved Polling with Stop) based on polling scheme is efficient because OLT assigns available time portion to each ONU given the request information from all ONUs. Since the IPS needs an idle time period on uplink between two consecutive frame transmission periods, it wastes time without frame transmissions. In this paper, we propose a dynamic bandwidth allocation algorithm to increase the channel utilization on uplink and evaluate its performance using simulations. The simulation results show that the proposed Two-phase Cycle Danamic Bandwidth Allocation(TCDBA) algorithm improves the throughput about 15%, compared with the IPS and Fast Gate Dynamic Bandwidth Allocation(FGDBA). Also, the average transmission time of the proposed algorithm is lower than those of other schemes.

• Journal of the Korean Home Economics Association
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• v.27 no.2
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• pp.75-83
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• 1989

In this study, effect of heat treatment on phytic acid, phosphorus compounds, and minerals in Korean soybean varieties was investigated. Results were summarized as follwo: 1. In the soybeans tested, protein content ranged from 34.6 to 44.6%, lipid content from 15.4 to 20.2%, fiber content from 4.8 to 6.1% and ash content from 4.5 to 5.9%. 2. Content range for phytic acid in soybean varieties was 1,300 to 1,542mg/100g and its mean was measured 1,392mg/100g. With increasing of the temperature, the phytic acid tends to be destroyed, especially at 6$0^{\circ}C$ the loss was averaged about 20%. 3. Total phosphorus content in soybean ranged from 607 to 681mg/100g and the decending order of phosphors content in soybean varieties was Millyang > Hwangkeum > Kwangkyo > Danyoup > Hill > Jangyoup. It was also destroyed with increasing temperature. 4. Phytate phosphorus content range in soybean was from 315.6 to 318.0mg/100g and decreased with increasing temperature. 5. Inorganic phosphorus content ranged from 95.5 to 110.0mg/100g and it was increased by temperature rising among soybean varieties. 6. Phytate phosphorus to total phosphorus ratio ranged from 5.2 to 5.7 and decreased by temperature rising. 7. The content of nonphytate phosphorus varied widely between soybean varieties and decreased with temperature increase. 8. The content of calcium, iron and magnesium ranged from 15.7 to 25.7mg/100g from 8.8 to 16.8mg/100g and from 121.9 to 143.6mg/100g respectively. The content of Mg showed small difference among soybean varieties. The change of mineral content with heat treatment in soybean did not give any meaningful change mineral content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.4 no.1
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• pp.19-23
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• 1975

From a study of the nutrient and gelation substances in Korean persimmon such as Jangdongsi, Pasi, Teabongsi, Kurigam, Nabjackgam, Gamsi and Hucks: The results obtained are summerized as follows: 1. According as persimmon changes into mellowed persimmon in the same kind the ammounts of sugar was increased, while the ammounts of fiber was decreased, but there was little difference in the other nutrient contents. 2. The ratio of 'Ca' and 'P' in persimmons in generally balanced at 1 : 2.5 3. Compared to the standard combination ratio of gelation substance, pectin in the persimmons was over but acid and sugars were very low.

• Fashion & Textile Research Journal
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• v.16 no.1
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• pp.145-152
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• 2014

The usage of textile-based sensors has increased due to their many advantages (compared to IT sensors) when applied to body assessment and comfort. Textile-based sensors have different detecting factors such as pressure, voltage, current and capacitance to investigate the characteristics. In this study, textile-based sensor fabrics with sheath-core type conductive yarns were produced and the relationship between capacitance changes and applied load was investigated. The physical and electric properties of textile-based sensor fabrics were also investigated under various laminating conditions. A textile based pressure sensor that uses a sheath-core conductive yarn to ensure the stability of the pressure sensor in the textile-based sensor (the physical structure of the reaction characteristic of the capacitance) is important for the stability of the initial value of the initial capacitance value outside the characteristic of the textile structural environment. In addition, a textile based sensor is displaced relative to the initial value of the capacitance change according to pressure changes in the capacitance value of the sensor due to the fineness of the high risk of noise generation. Changing the physical structure of the fabric through the sensor characteristic of the pressure sensor via the noise generating element of laminating (temperature, humidity, and static electricity) to cut off the voltage output element to improve the data reliability could be secured.

• Journal of the Korean Home Economics Association
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• v.17 no.3
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• pp.13-21
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• 1979

The purpose of this study were : (1) to analyze the commercial sizes in Korea , (2) to investigate the designs and materials of one-piece dresses, and (3) to ascertain the prices and tendency to sale of dresses. A questionaire and the interviews with some producers were used for this study. The questionaire was made with many items after the pretest. For the statistical analysis, 99 dresses were used among 141 dresses which were examined. The observation of ten observers was made in markets(group A), department stores (group B), and commercial agents of manufacture (group C). The period of observation was from April 10 to May 4 , 1979. The results of this study indicated that : (1) According to makers , the commercial sizes in Korea were different. The sizes were based on only waist in group A , body measurements in group B, and either of them in group C. (2) In dress style, the box dresses were popular in three groups. (3) The type of sleeve in group A, B and C showed in following order : set in sleeve > dropped shoulder > raglan sleeve. (4) The most necklines were finished with collars. The shirtwaist collars were popular in group A and C and the flat collars in group C. (5) In dress material , cotton/polyester was popular in group A, wool in group B, and silk in group C. The use of natural fiber and color in three groups decreased in following order : C>B>A. (6) The prices of dresses were from 10,000 to 35,000 won in group A, form 23,8000 to 49, 800 won in group B, and from 12,500 to 90,000 won in group C. (7) In case of group C, the elements which had influence on sale were color, design, and price.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.2
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• pp.449-454
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• 2006

This research was planned and executed to evaluate how the nutritional composition and antioxidants contents and antioxidative activity of Hongsambak. Also, can effect health conditions of people who are suffering from diet-related disease like obesity and hyperlipidemia by taking healthy foods with Hongsambak in a form of nutritional supplement with our daily meals. With this observation, we found out that Hongsambak has high content of dietary fiber and effect on antioxidative activity. We concluded that we could apply the components in a form of various foods. The information we received from this conclusion will be a basic information on how we can apply oriental medicinal resources into other foods and in the field of functional food research, which already draes sizable attention world-wide.

• International Journal of Human Ecology
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• v.9 no.1
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• pp.17-27
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• 2008

Black garments can lose color, image, and be the main cause of color staining when washed with other laundry that can cause color contamination from interaction with other garments. To know the fiber-based dye fastness for colored garments, 4-5 pieces of various fibers of different fabrics were selected; cotton, linen, wool, silk, rayon, acetate, polyester, and nylon. To determine the colorfastness to washing and crocking, the black fabrics were washed with alkali and neutral detergents under the Laund-O-Meter method under the Crockmeter method. In an alkali detergent laundering conditions, most colored samples did not undergo color or light fastness. However, most of the stained fabrics slightly changed in K/S values while other samples underwent severe changes. With neutral detergent laundering, sample fabrics underwent less shrinking, and had less naps. The stained fabrics also underwent less change in K/S values. With time-repeatedly-washing the original sample went through colorfastness to lose color. In crocking fastness, most samples produced good to excellent results under dry conditions but produced relatively low crocking fastness under wet conditions. Natural fibers especially showed lower crocking fastness than artificial fibers. In conclusion, garments of the same color should be laundered together. The black garments that are washed using neutral detergents can decrease the amount of damage from color change. While it is the responsibility of garment producers to provide appropriate quality indications they should also provide adequate instructions for consumers to understand and appropriately cope with the quality indications in order to contribute to establishing a correct laundering method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.523-526
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• 2004

가입자단에서의 병목현상 해결과 통신방송융합서비스의 제공을 위해 가입자망 기술은 디지털화된 HFC와 상하향 100Mbps이상의 속도를 제공하는 FTTH(Fiber To The Home)로 진화될 것으로 예측되며, 궁극적으로는 FTTH로 수렴될 것으로 전망되고 있다. FTTH는 통신과 방송이 융합된 다양한 신규서비스로 새로운 수익을 창출할 것으로 기대되나, 대규모 투자가 필요한 상황에서 정확한 수요 예측은 통신 회사들의 네트워크 구축 관련 의사결정에 필수적인 요인이다. 이를 위해 본 논문에서는 경쟁서비스로 천이가 용이한 통신서비스의 특징을 고려하여 FTTH의 수요예측을 실시하였다. 1차 전문가 설문을 통해 서비스간 전이형태를 모형화하였으며, 이를 토대로 FTTH 서비스로의 천이에 의해 추가적인 확산이 일어나는 변형된 Bass모형을 제안하였다. FTTH 서비스의 확산요인을 분석한 후 이를 토대로 2차 전문가 설문을 통해 각 계수를 추정하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5A
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• pp.317-325
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• 2012

In this study, to evaluate the shrinkage behavior of ultra high performance fiber reinforced concrete (UHPFRC) under restrained condition, restrained shrinkage test was performed according to ring-test mostly used at home and abroad. Ring-test was performed with the various thicknesses and radii of inner steel ring to give different degree of restraint. Free shrinkage and tensile tests were carried out simultaneously to estimate the degree of restraint, stress relaxation, and shrinkage cracking potential. Test results indicated that the average steel strain and residual tensile stress were reduced as the thicker inner steel ring was used, whereas degree of restraint was increased. The steel strain, residual tensile stress and degree of restraint were hardly affected by the size of radius of inner ring. In the case of all ring specimens, shrinkage crack did not occur because the residual tensile stress was lower than the tensile strength. About 39~65% of the elastic shrinkage stress was relaxed by the sustained interface pressure, and the maximum relaxed stress was increased as the thicker inner ring was applied. Finally, the degree of restraint with age was predicted by performing non-linear regression analysis, and it was in good agreement with the test results.

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.186-187
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• 2002

광통신의 최종 목적은 각 가정까지 광섬유를 연결하여 일반인들도 많은 정보를 신속하고 쉽게 접할 수 있게 하는 것, 즉, 광가입자망(Fiber To The Home, FTTH)의 실현이라고 할 수 있다. 그러나 여러 가지 문제점으로 인해 아직까지는 일부 실험 지역 내에 국한되어 있다. 광가입자망의 실현을 위한 이론적 방법으로 광섬유를 정보 전달소에서 각 가정까지 직접 연결하는 것이 있으나, 이 방법은 경제적 면에서 경쟁력을 갖출 수 없을 뿐 아니라 물리적인 부피 증가로 인해 현실적으로 실현 불가능하다고 할 수 있다. (중략)