• Title/Summary/Keyword: Dividing

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Comparison of Injection Uniformity as the Dividing Plate Installation in Fuel Manifold (연료 매니폴드내의 분리판 장착에 따른 분사균일성 비교)

  • Yoo Doc-Koon;Cho Won-Kook;Seol Woo-Seok
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2006.05a
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    • pp.130-134
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    • 2006
  • The injection uniformity of the fuel manifold in a liquid rocket engine has been analyzed with dividing plates to improve the cooling performance at the face plate. Three dimensional computational fluid dynamics analysis has been performed to compare the injection uniformity for 5 candidate designs and has been verified to compare with the measured data for the optimal manifold design. For the case I and II, the coolant mass flux increases as the whole working fluid is enforced to flow under the dividing plate. The injection uniformity decreases due to the variation of mass flux at the end of dividing plate and the concentration of mass flow rate at the center of manifold. However case III and IV have uniform injection performance due to reduced mass flux concentration as the coolant can flow along both upper passage and lower passage of the dividing plate. Among the candidate designs, case IV is thought to be the optimal dividing plate with regard to cooling performance and injection uniformity.

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An Exploratory Study for Dividing Fashion Product Buyers (패션 시장세분화를 위한 탐색적 연구)

  • Kim, Yeon-Hee;Lee, Kyu-Hye
    • The Research Journal of the Costume Culture
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    • v.19 no.2
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    • pp.360-375
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    • 2011
  • The fashion market focuses on consumers and maximizes consumers' satisfaction. The fashion market has been segmented to better satisfy the variety of consumer group. Although market segmentation has been studied, efficiency and effectiveness of market segmentation continuously bring problems. Also, problems of prediction about real consumer behavior, and efficiency and effectiveness of standards are pointed out. The purpose of this study is to determine the most important variables for dividing fashion product buyers. This study was designed as qualitative study and in-depth interview was conducted. The in-depth interview was conducted with five experts in fashion intelligence agency. In-depth interview was completed by an analytic induction and an investigator triangulation. Questions were about characteristics, demographic characteristics, important factors and fashion buying relationship, and interests of current clothing shoppers. The results of qualitative research demonstrated that clothing shoppers, with their valuable consumption and selective buying behaviors, seek differentiated products. They also long for high quality apparel for its price, because of their valuable consumption and price centered tendency. They illustrated active sides, such as enthusiastic information searching and emotional or experiential consumption, rather than attitudinal sides. The variables for dividing fashion product buyers included: "innovative seeking", "symbolic seeking", "personalized seeking", "quality-seeking", "selective seeking", "price-seeking", "utility-seeking", "hedonic seeking", "sensitive seeking", "brand-seeking", "digital seeking", "information-seeking", and "eco-seeking".

A Study on Operations with Fractions Through Analogy (유추를 통한 분수 연산에 관한 연구)

  • Kim Yong Tae;Shin Bong Sook;Choi Dae Uk;Lee Soon Hee
    • Communications of Mathematical Education
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    • v.19 no.4 s.24
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    • pp.715-731
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    • 2005
  • There are five contexts of division algorithm of fractions such as measurement division, determination of a unit rate, reduction of the quantities in the same measure, division as the inverse of multiplication and analogy with multiplication algorithm of fractions. The division algorithm, however, should be taught by 'dividing by using reciprocals' via 'measurement division' because dividing a fraction by a fraction results in 'multiplying the dividend by the reciprocal of the divisor'. If a fraction is divided by a large fraction, then we can teach the division algorithm of fractions by analogy with 'dividing by using reciprocals'. To achieve the teaching-learning methods above in elementary school, it is essential for children to use the maniplatives. As Piaget has suggested, Cuisenaire color rods is the most efficient maniplative for teaching fractions. The instruction, therefore, of division algorithm of fractions should be focused on 'dividing by using reciprocals' via 'measurement division' using Cuisenaire color rods through analogy if necessary.

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Study on Dividing Two-phase Annular flow in a Horizontal Micro T-junction (수평 마이크로 T 자관에서의 2상 환상류 유동분배에 관한 연구)

  • Lee, Jun-Kyoung;Jo, Seong-Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.1
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    • pp.16-22
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    • 2011
  • The objective of the present study is to investigate the dividing two-phase flow in a horizontal micro T-junction with the same rectangular cross section, $800\;{\mu}m{\times}800\;{\mu}m$, experimentally. Air and water were used as the test fluids. The superficial velocity ranges of air and water were 15~20 m/s and 0.11~0.2 m/s, respectively. Dividing flow characteristics at the micro T-junction are different from those at the larger T-junctions (5~10 mm in hydraulic diameter). Compared with the results of previous works related with the T-junction with mini cross sections (about 5 mm), for lower range of gas separation, the fraction of the liquid separated through the branch decreases for the fixed fraction of the gas separation. But for higher range of gas separation, higher liquid separation could be found.

Analysis of Characteristics for a Dividing Flow in Open Channels (개수로 분류흐름에서의 특성분석)

  • Park, Seong-Soo;Lee, Jin-Woo;Cho, Yong-Sik
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.2
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    • pp.53-57
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    • 2009
  • The dividing flow in an open channel has a number of distinctive characteristics. One of these is that the separation zone interacts with a secondary motion along the inner wall of a branch channel, generating sediment accumulation. To investigate this phenomenon, a two-dimensional numerical model based on the shallow-water equations, RMA2, which calculates water surface elevations and horizontal-velocity components, was used to analyze the dividing flow. The obtained numerical results fully coincide with the laboratory measurements reported by Hsu et al.(2002). For the analysis of the numerical results, a separation zone-discharge rate relationship was proposed. To reduce the size of a separation zone, the topographies of diagonal and curved edges were proposed, smoothly connecting the upstream corner to branch channel.

Runoff Estimation Considering Dividing Watershed (유역 분할을 고려한 유출량 산정)

  • Lee, Jong-Hyeong;Yoon, Seok-Hwan
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.1 s.24
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    • pp.57-66
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    • 2007
  • The purpose of this study is both the variation of hydrologic topographical informations extracted by using WMS and the quantitative effect of rainfalll-runoff simulation due to dividing watershed. Miho stream basin in Geum river was selected by this study. Watershed dividing method are determined by area, channel slope and channel length. Hydrological response of divided watershed using Clark method, SCS method and Snyder method was compared with actual measured flood hydrograph. As a results, area-based watershed dividing method are particularly suitable the hydrologic applications using SCS method. This study can be used as basic data for the phase of the runoff variation in Miho stream basin.

A Study of Complex Distillation Arrangements Using Dividing Wall Columns for Improved Depropanizing, Debutanizing and Deisobutanizing Fractionation of NGL (천연가스액 중 프로판, 부탄, 이소-부탄의 개선된 분리회수를 위한 분리벽형 증류탑을 이용한 복합 증류배열에 관한 연구)

  • Nguyen, Van Duc Long;Jang, Sungkeun;Lee, Moonyong
    • Korean Chemical Engineering Research
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    • v.51 no.2
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    • pp.245-249
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    • 2013
  • The depropanizing, debutanizing and deisobutanizing fractionation steps of processing natural gas liquids were improved through studying complex distillation arrangements, including the double dividing wall column arrangement (DDWC), the sequence including a dividing wall column (DWC) and a bottom DWC (BDWC), and the sequence including a DWC and a BDWC with top vapor recompression heat pump. These arrangements offer benefits by decreasing reboiler and condenser power consumption. Reducing the number of columns and their diameters can potentially reduce construction costs. The result also showed that operating cost could be reduced most significantly through novel combinations of internal and external heat integration: bottom dividing wall columns employing a top vapor recompression heat pump.

A study of leggings patterns using a 3D virtual simulation program - Focused on the women in 30's - (3D 버츄얼 시뮬레이션을 이용한 레깅스 패턴 연구 - 30대 여성을 중심으로 -)

  • Shin, JiA
    • Journal of the Korea Fashion and Costume Design Association
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    • v.25 no.4
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    • pp.93-106
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    • 2023
  • The study is to develop and present a leggings pattern that is suitable for the human body by using a standard body type avatar for a female in her 30s. As a research method, the average body type was selected from adult women in their 30s, and the appearance was evaluated using the CLO software program. The data analysis of this study compared the dimensions and shape of each part by legging. The leggings pattern suggested based on the above research results was determine to be a total length of 80.6cm and hip length of 24cm, and the knee length was set by dividing the legging in half from the waist to the hem and then adding 5cm. These figures were evaluated higher than Company D in terms of the adequacy of the upper part of the front and rear plates of Company A as well as the adequacy of the knee lines. Company A's figures were applied and corrected. For the front plate, the waist circumference was divided by 4, and 3.5cm was removed, and the hip circumference was set by dividing the hip circumference by 4, and 3.8cm was removed. In the appearance evaluation results Company D was highly evaluated in the suitability evaluation of the waist and hips, and the waist and hips were set using the pattern of Company D. The length of the front panel was modified by dividing the hip circumference by 4 and adding 1.8cm to the length, and the length of the back panel was modified by dividing the hip circumference by 3 and adding 8cm after dividing the hip circumference by 0.8cm.

The Flow Characteristics in Dividing Ducts (분지덕트 내의 유동특성)

  • Lee, Haeng-Nam;Park, Gil-Moon;Lee, Duck-Gu
    • The KSFM Journal of Fluid Machinery
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    • v.5 no.4 s.17
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    • pp.19-25
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    • 2002
  • The flow characteristics in a bifurcated duct are investigated experimentally. Physical properties such as mean velocity vectors, mean vorticity, and total pressure distributions are obtained for three different Reynolds numbers (578, 620, 688) using PIV measurements and CFD analysis. Also, two different dividing ducts ($90^{\circ},\;60^{\circ}$) were selected for study. The results of this study would be useful to the engineers designing flow systems for heating, ventilation, air conditioning and waste-water purification plants.

Improvement of Efficiency about $TiO_2$ Layer Multi-dividing Effect in Dye-sensitized Solar Cell (염료감응형 태양전지의 $TiO_2$ Layer 다분할 효과에 따른 효율 향상 연구)

  • Son, Min-Kyu;Seo, Hyun-Woong;Lee, Kyoung-Jun;Hong, Ji-Tae;Kim, Hee-Je
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.425-427
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    • 2008
  • Active area of dye-sensitized solar cell (DSSC) has an effect on the efficiency of DSSC. As the active area increases, the efficiency goes down in a general way. This is caused by the increase of internal resistance in DSSC. The internal resistances are related to various resistant elements. The charge transfer processes at Pt counter electrode and the sheet resistance of TCO are two of these resistant elements. In this study, we try to divide the active area into several small sections in a large sized cell to reduce these two internal resistant elements. As a result, we find out that the fill factor is increased and then the conversion efficiency is improved as the number of dividing active area into several small sections is increased.

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