• Title/Summary/Keyword: Drawn model

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Numerical Study on the Characteristics of Dual-Mode Scramjet Isolator (이중 모드 스크램제트 격리부 특성에 대한 수치해석적 연구)

  • Deng, Ruoyu;Kim, Heuy Dong;Jin, Yingzi
    • Journal of the Korean Society of Propulsion Engineers
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    • v.19 no.5
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    • pp.31-36
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    • 2015
  • As one of the most promising propulsive systems in the future, the dual-mode scramjet engine has drawn the attention of many researches. Detailed flow features concerned with the isolator play an important role in the dual-mode scramjet system. The 2D numerical method has been used for the dual-mode scramjet with wind tunnel. To validate the ability of the numerical model, numerical results have been compared with the experimental results. Overall pressure distributions show quite good match with the experimental results. Back pressure has been studied for maximum pressure rising. According to the results, pressure distribution of supersonic inlet section is not influenced by back pressure. The shock train is pushed towards upstream as the back pressure increases. The maximum value of back pressure without inlet unstart goes up rapidly and then keeps constant when the isolator length increases. The optimal length of isolator section ($L/H_{th}$) is 8.7 in this model.

A Study on the Flow Characteristics around a Hull Form of Coast-Canal Going Pusher-Barge (연안-운하 연계수송용 푸셔-바지 선형주위의 유동특성에 관한 연구)

  • Kim, Sung-Yong;Lee, Young-Gill;Lee, Seung-Hee
    • Journal of the Society of Naval Architects of Korea
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    • v.38 no.1
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    • pp.9-26
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    • 2001
  • In this paper. the development of a pusher-barge hull form which enables the continuous transportation along the coast and canal is performed. For the design stage of the hull forms. these are developed for Kyungin canal which is will be drawn up as the next contribution project of the Korean government are adopted. The model tests for the designed ship are carried out in the Inha University Towing Tank and the numerical simulations are done with a finite difference method based on MAC scheme. At first, the experiments are performed with designed model ships from low speed to high speed including service speed(6knots) among the corresponding designed speed. Resistance characteristics of designed ships are compared with experimental results of other several pusher-barge hull shapes. Next, the numerical simulations are performed for three cases, that is pusher only, barge only and pusher-barge condition in the designed speed. Each calculations are carried out in deep and restricted water condition. The flow characteristics around hulls in the latter condition are compared with those in the former condition.

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Experimental Study on Nonlinear Behaviors of A 1:12 Scale 10-Story Reinforced Concrete Frame with Nonseismic Details (비내진 상세를 가진 1:12축소 10층 R.C.골조의 비선형 거동에 관한 실험 연구)

  • Lee, Han-Seon;Kang, Kyi-Yong
    • Magazine of the Korea Concrete Institute
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    • v.11 no.1
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    • pp.255-266
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    • 1999
  • The objective of this experiment is to observe the elastic and inelastic behaviors of high-rise reinforced concrete frames having non-seismic details. To do this, a building frame designed according to Korean seismic code and detailed in the Korean conventional practice was selected. A 1:12 scale plane frame model was manufactured according to similitude law. A reversed lateral load test and a monotonic pushover test were performed under the displacement control. To simulate the earthquake effects, the lateral force distribution was maintained to be an inverse triangle by using a whiffle tree. From the tests, base shears, crack pattern, local rotations in the ends of critical members and the relations between interstory drift versus story shear are obtained. Based on test results, conclusions are drawn on the implications of the elastic and inelastic behaviors of a high-rise reinforced concrete frame having non-seismic details.

Behavior of Pile Groups in Granite Soil Under Lateral Loading (화강풍화토에서 수평력을 받는 무리말뚝의 거동)

  • Ahn, Kwangkuk;Ko, Pilhwan
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.5
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    • pp.69-73
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    • 2009
  • In this study, three dimensional numerical analyses were performed with variation of pile spacing (S=3D, 4D, 5D) to compare the behaviour of single pile and pile group with cap in granite soil. In order to compare and analyze the lateral resistance of single pile and pile group by changing pile spacing, the pile group with array of $1{\times}3$ was employed. To reduce the computation time the symmetric boundary condition was used. And Druker-Prager model and elasticity model were used for granite soil and for concrete pile and cap, respectively. Using the analyses results of pile group in granite soil under lateral loading, p-y curve for pile group and single pile with changing pile spacing was drawn. With p-y curve p-multiplier was evaluated. As a result of analysis, the value of p-multiplier was increased with increasing pile spacing under 1.0 due to pile shadow effects.

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Predicting the Accuracy of Breeding Values Using High Density Genome Scans

  • Lee, Deuk-Hwan;Vasco, Daniel A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.2
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    • pp.162-172
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    • 2011
  • In this paper, simulation was used to determine accuracies of genomic breeding values for polygenic traits associated with many thousands of markers obtained from high density genome scans. The statistical approach was based upon stochastically simulating a pedigree with a specified base population and a specified set of population parameters including the effective and noneffective marker distances and generation time. For this population, marker and quantitative trait locus (QTL) genotypes were generated using either a single linkage group or multiple linkage group model. Single nucleotide polymorphism (SNP) was simulated for an entire bovine genome (except for the sex chromosome, n = 29) including linkage and recombination. Individuals drawn from the simulated population with specified marker and QTL genotypes were randomly mated to establish appropriate levels of linkage disequilibrium for ten generations. Phenotype and genomic SNP data sets were obtained from individuals starting after two generations. Genetic prediction was accomplished by statistically modeling the genomic relationship matrix and standard BLUP methods. The effect of the number of linkage groups was also investigated to determine its influence on the accuracy of breeding values for genomic selection. When using high density scan data (0.08 cM marker distance), accuracies of breeding values on juveniles were obtained of 0.60 and 0.82, for a low heritable trait (0.10) and high heritable trait (0.50), respectively, in the single linkage group model. Estimates of 0.38 and 0.60 were obtained for the same cases in the multiple linkage group models. Unexpectedly, use of BLUP regression methods across many chromosomes was found to give rise to reduced accuracy in breeding value determination. The reasons for this remain a target for further research, but the role of Mendelian sampling may play a fundamental role in producing this effect.

Development Of Fashion Cultural Products using Traditional Korean Culture to Enhance Global Competition - Study on Face/Human Images for Digital Textile Printing -

  • Kim, Min-Ja;Lim, Ji-Ah;Yi, Jae-Yoon;Choi, Kyung-Hee
    • International Journal of Costume and Fashion
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    • v.6 no.2
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    • pp.11-27
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    • 2006
  • The purpose of this study is to develop highly valued fashion cultural items using Korean face and human images to enhance global competition. The methods of this study include: historical study on the face/human images which appear on the dress; design by stage according to Lamb & Kallal's apparel design process; development of products using digital textile printing technology; and case study by objective evaluation through Grant's alpha-beta model. The procedure and the results of this study are as follows: First, in the problem identification stage, the need to develop fashion cultural products of Korean face/human images which are symbolic, aesthetic, and functional was recognized in order to enhance global competition. Second, in the preliminary idea stage, the fashion cultural products and the components that meet the above 3 standards for design were determined and first design was drawn up. The source of the design was extrapolated from face/human images, which appeared on the murals of the ancient Korea, the portraits and custom paintings from the Chosun Dynasty. From these images, a total of 7 design series of T-shirts with an "ULGUL" logo, scarves, and artwalls were developed using "obangsaek" which are five Korean traditional colors including red, blue, black. white, and yellow on cottons and silks. Third, in the design refinement stage, based on the preference survey, more varying design methods were used to develop 25 new designs. Fourth, in prototype development stage, based on the preference survey conducted on fashion professionals and general public from the previous stage, which showed preference for T-shirts and scarves, 3 designs on T-shirts and 2 designs on scarves were printed and produced using the DTP (Digital Textile Printing). Fifth, in the evaluation stage, Grant's alpha-beta model was used to perform comparative evaluation on the symbolic, aesthetic, and functional criteria of the new designs over the existing ones. The new designs received excellent results in all three criteria and a special recognition was given to symbolism of the new designs.

A Study of Clothing Design in the Digital Age (디지털 시대의 의상 디자인 개발에 관한 연구)

  • 배리사;이인성
    • Journal of the Korean Society of Costume
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    • v.54 no.4
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    • pp.63-74
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    • 2004
  • This study shows that clothes to be just the same as the real thing can be Produced through the third dimension computer graphics, and then presents that not only the area of fashion design can be expanded in the virtual reality field by doing the simulation of the fashion show, but also the information can be made the real time public ownership and the communication can be fulfilled smoothly. In this study, analyzing the third dimension computer graphic programs to be used much at present, Alias Wavefront Company's Maya software which was the most effective in the clothes simulation and the clothes CAD SGS OptiTex 8.7 which went well substitutive for it were used of them. The conclusions of this study that got through the work manufacture are as follows: The first, if the file manufacturing in the clothes CAD by using the computer was stored, the pattern used 3D simulation was available because it could be summoned in 3D software. The second, if the data of DXF form in Maya program was summoned, they could not be applied by Maya Cloth supported in Nurbs only because they were recognized as the DXF_layer. So the curve along the outer lines of the pattern was drawn and Maya Cloth was applied to be possible to get the natural silhouette of clothes. The third, when the clothes were manufactured by 3D, if the draping character was applied according to the textile special quality, not only the control of textile's thickness, weight, quality feeling, and silhouette was available, but also the clothes were available to graft the special textile materials. The fourth, the natural motion of model was produced by capturing the actual model's walking action In order to produce the fashion show motion and also the dynamic fashion show was available by the angle of camera, the establishment of lighting, and etc. in the final rendering. The clothes manufactured by 3D are available to change the design by changing the materials, or by adding the details, or by utilizing the special materials on clothes. Therefore, the trial and error following at the clothes manufacture can be reduced. But the elevation of the rendering speed, the price down, the strengthening of personal security, and etc. are required.

Moment Analysis (MA) of Lysozyme in Cation Exchange High Performance Liquid Chromatography (HPLC) (양이온교환 고성능액체크로마토그래피에서 라이소자임의 모멘트 분석)

  • Ko, Kwan Young;Kim, In Ho
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.487-493
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    • 2016
  • The moment analysis of lysozyme was implemented using chromatograms that were obtained from weak cation exchange column in high performance liquid chromatography system. Three elution sodium phosphate buffers containing 1.0, 0.75, 0.5M sodium chloride were used. Experiments were conducted by varying flow rate, elution sodium chloride concentration, and lysozyme solute concentration. The general rate (GR) model was employed to calculate the first moment and the second moment. By plotting $L/u_0$ vs. $({\mu}_1-t_0)/(1-{\varepsilon}_e)(1-{\varepsilon}_i)$] equilibrium constants (K) were obtained from first moment analysis. Intra-particle diffusivity was obtained from theoretical plate number data. Based on the results of moment analysis, van Deemter plots were drawn in order to investigate the contributions of $H_{ax}$, $H_f$, and $H_d$ to total Height Equivalent to a Theoretical Plate (HETP, $H_{total}$). The effect of intra-particle diffusion ($H_d$) was the most dominant factor contributing to HETP while external mass transfer ($H_f$) was negligible factor.

An Integrated Model of Cybersickness: Understanding User's Discomfort in Virtual Reality (사이버멀미 통합 모델: 가상현실 사용자의 불편감 현상 연구)

  • Chang, Eunhee;Seo, Daeil;Kim, Hyun Taek;Yoo, Byounghyun
    • Journal of KIISE
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    • v.45 no.3
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    • pp.251-279
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    • 2018
  • Users can experience cybersickness when interacting with virtual reality (VR). The symptoms of cybersickness are similar to those of motion sickness which include eye fatigue, disorientation, and nausea. Despite the longstanding interest of user's discomfort, inconsistent results have been drawn on the underlying mechanisms and solutions of cybersickness. In this study, we propose an integrated view of cybersickness connecting causes of the symptoms, human perception model, and measurements of cybersickness. Cybersickness-related factors of previous research are reorganized into content, hardware, and human factors as well as analyzed in terms of VR fidelity. Also, pros and cons that measure the degree of cybersickness are discussed.

Preventive Effects of Nokyongdaebotang on Hyperlipidemia Rats (녹용대보탕(鹿茸大補湯) 투여에 의한 흰쥐의 고지혈증(高脂血證) 예방(豫防)에 관한 실험 연구)

  • Lee Sang-Woon;Jeong Chan-Gil;Kuim Kwang-Ho;Soh Kyung-Sun
    • Journal of Society of Preventive Korean Medicine
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    • v.7 no.2
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    • pp.107-119
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    • 2003
  • In order to study the preventive effects of hyperlipidemia depending on endogenous and exogenous methods of induction, after observing what happens when Nokyongdaebotang, a strengthening up treatment is orally administrated into the ways that cause hyperlipidemia either by the exogenous hyperlipidemia condition model method, which is the way where you orally administrate the cholesterol that was dissolved in olive oil, or the endogenous hyperlipidemia model method, where it uses the injecting the Triton WR-1339 vein method, or to the already inducted white rats, the following conclusions could be drawn. 1. The endogenous induction method, cholesterol diet, helps preventing Total Cholesterol, TG, and LDL-Cholesterol, Free Fatty Acid, Phospholipid's augmentation within the blood in the white rats that is being induced or just inducted with hyperlipidemia 2. The exogenous induction method, Triton WR injection, helps preventing Total Cholesterol, TG, and LDL-Cholesterol, Free Fatty Acid, Phospholipid's augmentation within the blood in the white rats that is being induced or just inducted with hyperlipidemia 3. The HDL-Cholesterol did not increase in regard. This is considered to be because when the geological features the HDL-Cholesterol increases proportionally. In deference to the above results, Nokyongdaebotang, which strengthens the vitality, showed that it helps prevent white rats that is being induced or just inducted with hyperlipidemia no matter whether it is endogenous or exogenous.

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