• Title/Summary/Keyword: Dart

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Numerical Analysis of Ramjet Inlet Duct Flows According to Flying Velocity (램제트 비행속도에 따른 Inlet Duct내 유입공기 유동장의 수치해석)

  • Ko, Hyun;Yoon, Woong-Sub;Lee, Jin-Ho
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2002.04a
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    • pp.57-58
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    • 2002
  • 램제트는 다른 여러 추진시스템에 비하여 획기적으로 증가된 사거리를 가지므로 가용범위의 확대는 물론, 목표물 타격 시 높은 명중률과 낮은 격추율을 가지는 효과적인 추진 시스템이다. 램제트 엔진을 장착한 미사일로는 프랑스의 Griffon, ASMP, 미국의 Bomarc, Talos, 영국의 Bloodhound, Sea dart, 소련의 SA4, SA6 등을 비롯하여 많은 종류가 개발되어 실전 배치되었다. 근래 들어 램제트는 군사전략과 전술적인 목적 이외에도 민간용으로도 그 실용성이 강조되고 있어 그 중요성은 날로 더할 것으로 예측된다. 램제트는 일반적인 공기흡입식 엔진과는 달리 엔진 내부에 기계적으로 구동되는 부분이 없이 충격파를 통과하면서 공기의 압력이 높아지는 현상인 램압축 현상을 이용하여 공기를 압축하게 되므로 엔진의 구조가 간단하고, 상대적으로 높은 비추력과 추력/중량비를 가진다. 램제트는 정지 상태에서는 작동되지 않으며 사용 가능한 최소의 압력비를 줄 수 있는 비행 마하수에 도달해야 램제트가 작동하게 된다. 따라서 이러한 비행속도를 줄 수 있는 별도의 추진장치가 필요하게 되는데 이와 같은 보조 추진장치로 부스터를 사용한다. 부스터가 엔진의 내부에 장착된 램제트를 일제형 램제트 (IRR: integral Rocket Ramjet)라 부르며, 현대의 전략미사일과 민간용 초음속 항공기의 엔진에 도입되어 활발한 연구가 진행 중이다. 램압력을 이용하여 압축하므로 램제트의 설계시 설계점 비행 속도에서 전압력 손실이 최소가 되도록 설계되어야 하며, 이를 실험이나 수치해석을 통해 확인하여야 한다.

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Analyzing empirical performance of correlation based feature selection with company credit rank score dataset - Emphasis on KOSPI manufacturing companies -

  • Nam, Youn Chang;Lee, Kun Chang
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.4
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    • pp.63-71
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    • 2016
  • This paper is about applying efficient data mining method which improves the score calculation and proper building performance of credit ranking score system. The main idea of this data mining technique is accomplishing such objectives by applying Correlation based Feature Selection which could also be used to verify the properness of existing rank scores quickly. This study selected 2047 manufacturing companies on KOSPI market during the period of 2009 to 2013, which have their own credit rank scores given by NICE information service agency. Regarding the relevant financial variables, total 80 variables were collected from KIS-Value and DART (Data Analysis, Retrieval and Transfer System). If correlation based feature selection could select more important variables, then required information and cost would be reduced significantly. Through analysis, this study show that the proposed correlation based feature selection method improves selection and classification process of credit rank system so that the accuracy and credibility would be increased while the cost for building system would be decreased.

Structural Characteristics of the Mongolian Costume called YosunOja - Focus on the Medieval Finds from the Tomb Minshui, Neimenggu - (몽골 요선오자의 구조적 특징 - 내몽골 명수묘 출토 요선오자를 중심으로 -)

  • Kim Moon-Sook
    • Journal of the Korea Fashion and Costume Design Association
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    • v.6 no.3
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    • pp.9-18
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    • 2004
  • This study focuses on the medieval Mongol costume called YosunOja. This dress consists of a blouse and a skirt, and some lines on the waist part. The purpose of the study is to analyse the structural characteristics of this costume, especially on the medieval remains from the tomb Mingshui in the district of Neimenggu. It can be analysed that this costume has three structural characteristics, which are the functional structure, sumptuous one, and the idea of Buddhism. The functional structure consists of the style with a blouse and a skirt, which gives enough surplus for the movement, the back-slash for the ease of the riding, and the dart in the front line which eliminates unnecessary surplus. The sumptuous structure is the many lines of the waist which show the maximization of the decoration, the extraordinary long sleeves, and the use of the expensive gold brocade which shows the wealth of the dresser. And also, the cutting of the fabric into the numerous segment may mean the medieval Mongols believed in Buddhism.

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A Study on Pattern of Concert Dress Preference Design (연주복 선호 디자인에 따른 패턴 연구 - 피아노와 성악 중심으로 -)

  • Park, Sung-Yul;Hong, Jung-Min
    • Fashion & Textile Research Journal
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    • v.5 no.5
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    • pp.465-469
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    • 2003
  • The present study revealed; that (1) The students majoring in a piano course were the preference type of the performance dress - best line was designed of upper form chest. It was 1.5cm shorter than armhole line, the princess line was preferred Top one piece without sleeves which was designed with slim by bottom line through west dart form best line. The expression method was showing embroidery and bidding, colors were in order to white, ivory, black and blue style. The material was in order to silk with glorious shinning, silk satin and race style. (2) The students majoring in a vocal music were the preference type of the performance dress - the princess line was designed shorter, the west line of back and forth was preferred the one piece of bulk style divided with three partitions. Neck line was 5cm shorter than the middle of back, 9cm shorter than the side neck position, 9cm shorter than the middle of forth, sweet heart neck line with circular sleeve designed 7cm shorter than the side neck position. Colors were in order to ivory, red and yellow style. The material was in order to silk with glorious shinning silk satin and race style.

A Study on the Low Waist Slacks Pattern for the Schoolgirl of a Tween Generation (트윈세대 여학생을 위한 로우 웨이스트 슬랙스 패턴 연구)

  • Shin, Ki-Young;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.18 no.6
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    • pp.1165-1178
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    • 2010
  • This study is aimed at developing low waist slacks pattern with high satisfaction measurements and beauty for the tween generation girls. For this study, the research method was as follows. By extracting and analyzing industrial and educational slacks pattern, beautiful and motion-suitable slacks pattern will be created. This study presents the ideal slacks pattern that has great fit to tween generation girls by comparing and analyzing the previous 2 slacks pattern studies and the real clothing test. The constructed pattern in the 1st step was modified and adjusted from the best industrial patterns' the location of waist line, waist line gradient, rear waist bottom crotch, hip bottom crotch, dart length, the ease of hip girth, the fitness of rear bottom crotch line which were not well-estimated. The 2nd step was appearance and movement test based on the 1st study. In The 3rd step, the 2nd step was chosen as the final slacks study pattern for its superior appearance & movement satisfaction comparing with other patterns.

A Study on the Bodice and Sleeve Patterns for Middle-aged Women (중년여성을 위한 기본 원형설계)

  • 정혜락;함옥상
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.1
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    • pp.105-115
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    • 2000
  • This study was intended to find body pattern of middle aged women and make new experimental basic pattern for upper-half of the body for them. This experimental pattern on the idea of body pattern analysis was prepared. For experimental pattern, the prototype basic model was chosen with the best qualified D model from the four meaningful existing patterns. After several steps of correction experimental pattern was made. Comparing with basic D model, the new experimental pattern composed of additional bust girth by 1cm, wider back waist by 0.5cm than front waist and additional armhole by 0.5cm keeping the same size for back and front widths. Making a shoulder line up by 3cm the armhole became deeper accordingly and the room for girth has been transferred to length. Front neck girth became deeper downward but back neck girth risen a little bit. Side line of the bodice formed with inward slope taking from the waist line by 2cm. Instead of dart, modified side line slope was more practical by its function and appearance. Abdominal girth which is lower than waist girth by 8.5cm kept in same size with bust girth. Then abdominal girth became more comfortable. New experimental pattern with changes has been examined in function and appearance. In conclusion, the new experimental basic pattern for the middle-aged women has been proved more practical for both in bodice and sleeve than other existing ones in terms of function and appearance.

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Brassiere Pattern Design Using the 3D Information - Application of Ruled Surface- (3차원 정보가 반영된 브래지어 패턴 설계 -Ruled surface의 활용-)

  • 이예진;홍경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.11
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    • pp.1536-1543
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    • 2004
  • Garment is made by a 2D pattern and should be fitted to a human body which has 3D characteristics. Therefore, to design a pattern more effectively, the use of 3D information of a human body and the investigation of relationship between the 3D garment and 2D pattern are necessary. In this work, ruled surface method was used to reflect the 3D information of a human body for a pattern design. The images of the brassiere line on the woman's dress form were captured by phase-shifting projection moire system and the 3D information on the design line was obtained. 2D patterns on the various parts of the brassiere were developed directly from the 3D data by the ruled surface method. In addition, design line, the area and the amount of dart were quantified. And then we verify the appropriateness of the ruled surface method to the 2D pattern development by measuring the distribution of the space between women's figure and segmented clothing item. It was found that the ruled surface method is useful to transform the 3D design line to the 2D pattern, if we followed the steps suggested in this paper.

Analysis on Torso Somatotype of Adult Females by Tight Fitting Technique (입체재단에 의한 성인여성의 체간부 유형분석)

  • 홍정민
    • Journal of the Korean Society of Costume
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    • v.42
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    • pp.163-172
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    • 1999
  • The purpose of this study is to classify the types of torso of adult females using the tight fitting technique and pattern development figure. The subjects are 106 females of 19 to 24 years old. 59 different items are measured from body surface development and analyzed by factor analysis and cluster analysis. The results are as follows; 1. Eight somatotype factors are obtained through factor analysis and orthogonal rotation by the method of Varimax Factor 1 is the length of upper body factor 2 the length of lower body factor 3 the circumference and width of the back of upper body factor 4 the circumference and width of front torso factor 5 the dart type of the back of upper body factor 6 the size of the back neck factor 7 the type of the front shoulder and factor 8 the size of the back arm hole. 2. As a result of cluster analysis the somatotype of torso is classified into 5 types. Type 1 is normal in length circumference and width of upper body. Type 2 is shortest length circumference and width of torso. Type 3 is long in length circumference and width of torso. Type 4 is normal length and short in circumference and width especially short in bust circumference. Type 5 is longest in length circumference and width of torso.

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A Study on the Production Conditions of Circular Knit of Domestic Women's Apparel Industry (국내 여성복 업체의 환편니트 제품 생산현황 조사)

  • Oh, Ji-Yeong
    • Fashion & Textile Research Journal
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    • v.18 no.5
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    • pp.637-646
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    • 2016
  • The goal of this study is to provide basic data on developing circular knit basic pattern for women in their 20's. Production conditions of circular knit product pattern making among domestic women's apparel industry was researched, and collected data on sizes and ease amounts from woven and circular knit pattern were compared and analyzed. According to the result of the survey, product measurements adjusted to the actual body size fit for the brand's image were used, and the common problem among manufacturers and consumers regarding circular knit products turned out to be change in size and form due to stretching. For the basic pattern of circular knit, stretching quality was reflected in the woven basic pattern based on plain stitch(single knit) and then dart was removed and ease amount was reduced. The result of looking into size and ease amount about woven and circular knit torso & sleeve block shows that there is a significant difference among chest circumference, hip circumference, bi-shoulder length, interscye back, interscye front, scye depth, upper arm circumference and wrist circumference, and it was clear that circumference and width on the areas around the wrist tended to fit around the body more when circular knit was used instead of woven fabric.

A Study on the Development of a Torso Prototype for Chinese Women

  • Chang, Hee-Kyung;Sohn, Hee-Soon;Im, Soon
    • Journal of Fashion Business
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    • v.7 no.6
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    • pp.32-49
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    • 2003
  • The purpose of this study is to examine the characteristics and differences of Chinese adult women's torsos by sampling Chinese college women and measuring their torsos and thereupon, develop a torso prototype fitting their torso characteristics and thereby, improve the fitness of the clothing products exported to China. For this purpose, body sizes were comparatively measured between Chinese and Korean college women to determine the differences of body shapes between the two groups, and thereupon, a torso prototype was produced. Then, the prototype was checked with senses, and was modified and complemented three times. In the final torso prototype, waist front and back length was reduced in consideration of Chinese women's body shapes, and neck side - nipple length was extended because Chinese women's chests are pushed out, and additionally, front shoulder dart volume was readjusted. In addition, the fitness of the prototype was tested by setting the S and L size intervals as well as the basic size (M). It is hoped that the results of this study would be useful to the Korean clothing companies exporting their products to China.