• 제목/요약/키워드: material factors

검색결과 4,088건 처리시간 0.03초

피삭제와 공구재종의 상관관계에 근거한 절삭조건의 최적화 (Optmization of Cutting Condition based on the Relationship between Tool Grade and Workpiece Material(I))

  • 한동원;고성림
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 춘계학술대회 논문집
    • /
    • pp.1038-1043
    • /
    • 1997
  • To adapt the neural network proess for the purpose of determination of optimal utting onditions (optimal cutting speed and feed rate), some selection strategies for the machining factors are necessary, which is considered planning cutting process. In this case, factors that have both nonlinearity and strong relationship must be selected. Although tool grade and chemical properties of workpiece material have strong effect to cutting speed, it's not easy to find a analytic relation between them. In this paper, a mathematical method for determining the optimal amount of cutting (depth of cut, feed rate) is presented by tool goemetry and heat generation during cutting process. And various tool grade and workpiece material groups ase classified based on its chemical properties. Thier chemical composition and hardness are used as input pattern for neural network learnig. The result of learning shows the relationship between tool grade and workpiece material and it is proved that it can be used as a sub-system for automatic process planning system.

  • PDF

일축 압축하중 하 다공성 폴리우레탄폼의 재료비선형 거동 및 미세구조 변화 (Material Nonlinear Behavior and Microstructural Transition of Porous Polyurethane Foam under Uniaxial Compressive Loads)

  • 이은선;고태식;이치승
    • 한국재료학회지
    • /
    • 제27권12호
    • /
    • pp.688-694
    • /
    • 2017
  • Porous materials such as polymeric foam are widely adopted in engineering and biomedical fields. Porous materials often exhibit complex nonlinear behaviors and are sensitive to material and environmental factors including cell size and shape, amount of porosity, and temperature, which are influenced by the type of base materials, reinforcements, method of fabrication, etc. Hence, the material characteristics of porous materials such as compressive stress-strain behavior and void volume fraction according to aforementioned factors should be precisely identified. In this study, unconfined uniaxial compressive test for two types of closed-cell structure polyurethane foam, namely, 0.16 and $0.32g/cm^3$ of densities were carried out. In addition, the void volume fraction of three different domains, namely, center, surface and buckling regions under various compressive strains (10 %, 30 %, 50 % and 70 %) were quantitatively observed using Micro 3D Computed Tomography(micro-CT) scanning system. Based on the experimental results, the relationship between compressive strain and void volume fraction with respect to cell size, density and boundary condition were investigated.

Material attractiveness of unirradiated depleted, natural and low-enriched uranium for use in radiological dispersal device

  • Ahn, Jihyun;Seo, Hee
    • Nuclear Engineering and Technology
    • /
    • 제53권5호
    • /
    • pp.1652-1657
    • /
    • 2021
  • Nuclear materials can be utilized not only for peaceful uses, but also for military purposes; hence, the international community has devoted itself to the control, management and safeguarding of nuclear materials. Nuclear materials are of varying degrees of usability for development of nuclear weapons. Thus, several methods for assessing the attractiveness of nuclear materials for nuclear weapons purposes have been proposed. When these methods are applied to unirradiated depleted, natural, and low-enriched uranium (DU, NU, and LEU), they are certainly classified as non-attractive nuclear materials. However, when nuclear material attractiveness is to be evaluated for potential radiological dispersal device (RDD) uses, it is required to develop a different method for the different aspects and factors. In the present study, we derived a novel method for evaluating nuclear material attractiveness for use in RDD development. To this end, the specific activity and dose coefficient were identified as the two sub-factors, and, in consideration of those, the mass causing detrimental health effects was determined to be the main factor impacting on nuclear materials attractiveness. Based on this factor, the attractiveness of unirradiated DU, NU, and LEU for RDD use was qualitatively compared with that of 137Cs.

투과형 광탄성 실험법에 의한 지능성 FRP의 파괴지연 효과에 관한 연구 (A Study on the Effect of Fracture Delay of Intelligent FRP by Transparent Photoelastic Experimental Method)

  • 이효재;황재석
    • 대한기계학회논문집A
    • /
    • 제23권11호
    • /
    • pp.1904-1911
    • /
    • 1999
  • The most effective material in the shape memory alloy(SMA) is the TiNi alloy, because its shape recovery characteristics are very excellent. We molded the composite material with shape memory function. The fiber of it is $Ti_{50}-Ni_{50}$ shape memory alloy and matrix of it is epoxy resin(Araldite B41, Hardner HT903. Ciba Geigy), its adhesive and optical sensitivity are very excellent. It was assured that the composite material could be used as model material of photoelastic experiment for intelligent materials or structures. In this research, the composite material with shape memory function is used as model material of photoelastic experiment. Photoelastic experimental hybrid method is developed in this research, it is assured that it is useful on the obtaining stress intensity factor and the separation of stress components from only isochromatic data. The measuring method of stress intensity factor of intelligent material by photoelastic experiment is introduced. In the mode I state, we can know that stress intensity factors are decreased more than 50% of stress intensity factor of room temperature when temperature of fiber is greater than 4$0^{\circ}C$, prestrain greater than 5% and fiber volume ratio greater than 0.42% and that stress intensity factors are decreased by 100% when fiber volume ratio is greater than 0.84%, prestrain greater than 5% and temperature greater than 60 $^{\circ}C$.

INTERMINGLER에 대하여 (The Airjet INTERMINGLER is Widely Used in Textile Field)

  • 김은상
    • 기술사
    • /
    • 제33권5호
    • /
    • pp.33-37
    • /
    • 2000
  • Now many IHTERMINGLER manufactures are under developing new types which can decrease the air consumption and at the same time can improve the efficiency of operating. The material and surface finish of yarn chamber is important factors to make INTERMINGLER. Normally ceramic material and tungsten carbide is used for yarn chamber but now chemical diffusion process for metal is widely used for material and it is very successful considering the hardness of surface.

  • PDF

에폭시계 보수재료의 재료특성 및 내구성능 분석 (A Study on the Material Properties and Durabilities of Epoxy-Type Repairing Materials)

  • 김도겸;이장화;박승범
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
    • /
    • pp.659-664
    • /
    • 1997
  • RC structures can deteriorate for many defective factors. In the repair and retrofit works of concrete, epoxy resins are widely used as repair materials. The object of this study is to investigate the material properties and durabilities of epoxy resins which are commonly used in repairing concrete. The material properties such as line-expansion modulus, viscosity, microstructure and physical parameter as well as the durabilities such as gravity change, tensile strength, elongation change were carried out.

  • PDF

주축 설계에 영향을 미치는 베어링 파라미터에 관한 연구 (A Study on the Bearing Parameters Effect on Main Spindle Design of Machine Tool)

  • 한강근
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1997년도 추계학술대회 논문집
    • /
    • pp.94-100
    • /
    • 1997
  • The purpose of this study is to investigate the effects of operation factors of a typical main spindle system on its efficiency. Among important factors, material type of ball-bearing, bearing-lubricant type and main spindle bearing preload are taken into considered.

  • PDF

프로야구 경기환경요인이 관람만족에 미치는 영향 (Influence of Factors of Baseball Stadium Environment on Spectating Satisfaction of Professional Baseball)

  • 황선환;김홍설
    • 한국콘텐츠학회논문지
    • /
    • 제12권1호
    • /
    • pp.508-515
    • /
    • 2012
  • 이 연구는 프로야구 관람 만족에 영향을 미치는 다양한 요인의 규명을 통하여 프로야구 관람률 및 관람 만족을 제고시킴으로써 궁극적으로 건전 여가활동으로서의 관람 스포츠 문화를 정착시키는 데 그 목적이 있다. 이러한 목적을 달성하기 위하여 본 연구는 D시에서 열린 2011시즌 6월 14일 프로야구 경기 직접관람자를 모집단으로 설정한 다음 유층집락무선표집법(stratified cluster random sampling method)을 이용하여 표본을 추출하였으며 유효표본 614명을 최종 조사 자료로 활용하였다. 본 연구의 조사도구는 설문지였으며, Wakefield와 Sloan(1995), Hansen과 Gauthier(1989), Jeffrey(1997), Green(1995) 등이 개발하고 김홍설(1999)이 번안하여 사용한 설문지였다. 본 연구는 SPSSPC+ V. 18.0 프로그램을 이용하여 상관분석(correlation), 회귀분석(regression)을 실시하였으며 이를 통해 얻어진 연구결과 및 논의를 토대로 다음과 같은 결론을 도출하였다. 첫째, 경기장 요인은 관람만족에 영향을 미친다. 둘째, 관람 비용 요인은 관람 만족에 영향을 미친다. 셋째, 관람 촉진 요인은 관람 만족에 영향을 미친다.

패션 이미지 유형(類型)과 디자인 요소(要素)와의 관계(關係)(I) (A Relationship Between Fashion Image Types and Design Factors(I))

  • 김일분;유태순
    • 패션비즈니스
    • /
    • 제1권3호
    • /
    • pp.19-34
    • /
    • 1997
  • The role of fashion image in modern society is being diversified from product planning to consumer satisfaction. In this research, after surveying female college students, the diversified modern fashion image was patterned. On the analogy of the relationship between these patterned image and design factors, the following conclusion was obtained. 1. The most popular styles are jacket and pants suits, three-piece outfits, tight mini-skirts and X-silhouette. Little decoration is used in general. simplicity is shown as trend by utility fabrics in single color-black, brown, beige and blue-with no pattern. Various materials such as wool, cotton, wool or cotton blended with other materials, silk, satin, knit, lace, vinyl and leather are used. 2. Fashion image is divided into four factors; factors that show fad, dignity, activity and simplicity. 3. Factors that show fad; style of tops, material of bottoms and length of bottoms reflect fad. blousons, three-piece outfits, pants rather than skirts, X-silhouette and mini-skirts are prevailing. Vinyl, leather, knit, lace and satin are the materials well used. 4. Factors that show dignity; Style and material of tops, the way of top and bottom pieces are matched and length of bottom or pieces reveal the characteristics. Jackets, blouses, half-coats and one-piece outfits rather than two-pieces are popular. Tight skirts in natural or midi length or pleated skirts are common. Wool, wool blended with other materials, leather and X-silhouette are design factors that reveal dignity well. 5. Design factors that show active image; Straight pants, three-piece outfits, T-shirts, shirt -blouses, vests, and blausons are popular. Knit and lace are used for tops, leather and vinyl are used for bottom pieces and cotton is widely used. Y- or H-silhouette are used to show active image.

  • PDF

Preparation and Characteristics of Leather-like Material from Shark Intestines

  • Byun Hee-Guk;Je Jae-Young;Kim Se-Kwon
    • Fisheries and Aquatic Sciences
    • /
    • 제5권2호
    • /
    • pp.136-140
    • /
    • 2002
  • Every year fish skin, bone and intestines are discarded as processing waste material. The use of fish processing waste material is more economical and environmental-friendly. The leather-like material was produced using shark intestine. Physical charactistics such as tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were measured, and compared with those of a commercial leather product. The values of tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were $3.3kg/mm^2$, $53\%$, 13.0kg/mm and $18kg/cm^2$, respectively. Elongation $(l09\%)$ of the leather-like material coated with lacquer was higher than that of a commercial leather material, and the other factors were similar. The tensile strength and tongue tearing strength of the leather-like material was higher than those of shoes leather, but bursting strength was lower. These results suggested a potential value to use the leather-like material from shark intestines as a substitute for commercial leathers.