• Title/Summary/Keyword: ultra-high performance

Search Result 978, Processing Time 0.031 seconds

Computer Simulation and Control performance evaluation of Ultra Precision Positioning Apparatus using DC Servo Motor (DC Servo Motor를 이용한 초정밀 위치결정기구의 컴퓨터 시뮬레이션 및 제어성능 평가)

  • 박기형;김재열;윤성운;이규태;곽이구;송인석;한재호
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.9 no.6
    • /
    • pp.164-169
    • /
    • 2000
  • Recently, High accuracy and precision are required in various industrial field especially, semiconductor manufacturing apparatus, Ultra precision positioning apparatus, Information field and so on. Positioning technology is a very important one among them. As such technology has been rapidly developed, this field needs the positioning accuracy as high as submicron. It is expected that the accuracy of 10nm and 1nm is required in precision work and ultra precision work field, respectively by the beginning of 2000s. High speed and low vibration are also needed. This work deals with the design method and control system of Ultra precision positioning apparatus. Control performance and stability analysis were performed in advance by modeling and designing the controller with Simulink.

  • PDF

Machinability Evaluation of Endmill Tool through Development of Ultra-fine Grain Grade Cemented Tungsten Carbide Material (초미립 초경소재 개발을 통한 엔드밀 공구의 성능 평가)

  • 김홍규;서정태;권동현;김정석;강명창
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.10a
    • /
    • pp.865-869
    • /
    • 1997
  • In recent years, there has been increasing demand of ultra-fine grain graded cemented tungsten carbide material with high hardness and toughness which is used as high speed cutting tool for development in semiconductor, electronics and die/mold industry, which bring into limelight high-precision, high-efficient machining of sculptured surfaces. This paper deals with the performance of variation in the ultra-fine grain graded cemented tungsten carbide material such as grain size, hardness and density varied according to the volume of added elements, Co or TaC, and he changing of mixing, sintering process. Also, the performance of developing material with uniformed grain size of 0.5${\mu}{\textrm}{m}$ is compared with other domestics' & foreign companies' with analyzing and cutting performance testing.

  • PDF

HPC(High Performance Computer) Linux Clustering for UltraSPARC(64bit-RISC processor) (UltraSPARC(64bit-RISC processor)을 위한 고성능 컴퓨터 리눅스 클러스터링)

  • 김기영;조영록;장종권
    • Proceedings of the IEEK Conference
    • /
    • 2003.11b
    • /
    • pp.45-48
    • /
    • 2003
  • We can easily buy network system for high performance micro-processor, progress computer architecture is caused of high bandwidth and low delay time. Coupling PC-based commodity technology with distributed computing methodologies provides an important advance in the development of single-user dedicated systems. Lately Network is joined PC or workstation by computers of high performance and low cost. Than it make intensive that Cluster system is resembled supercomputer. Unix, Linux, BSD, NT(Windows series) can use Cluster system OS(operating system). I'm chosen linux gain low cost, high performance and open technical documentation. This paper is benchmark performance of Beowulf clustering by UltraSPARC-1K(64bit-RISC processor). Benchmark tools use MPI(Message Passing Interface) and NetPIPE. Beowulf is a class of experimental parallel workstations developed to evaluate and characterize the design space of this new operating point in price-performance.

  • PDF

A Review on Structural Behavior, Design, and Application of Ultra-High-Performance Fiber-Reinforced Concrete

  • Yoo, Doo-Yeol;Yoon, Young-Soo
    • International Journal of Concrete Structures and Materials
    • /
    • v.10 no.2
    • /
    • pp.125-142
    • /
    • 2016
  • An overall review of the structural behaviors of ultra-high-performance fiber-reinforced concrete (UHPFRC) elements subjected to various loading conditions needs to be conducted to prevent duplicate research and to promote its practical applications. Thus, in this study, the behavior of various UHPFRC structures under different loading conditions, such as flexure, shear, torsion, and high-rate loads (impacts and blasts), were synthetically reviewed. In addition, the bond performance between UHPFRC and reinforcements, which is fundamental information for the structural performance of reinforced concrete structures, was investigated. The most widely used international recommendations for structural design with UHPFRC throughout the world (AFGC-SETRA and JSCE) were specifically introduced in terms of material models and flexural and shear design. Lastly, examples of practical applications of UHPFRC for both architectural and civil structures were examined.

Creep Properties of Ultra High Strength Concrete at High Temperature under Loading (재하와 가열을 받은 초고강도 콘크리트의 크리프 특성)

  • Lee, Young-Wook;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Yoon, Min-Ho;Kim, Hong-Seop;Lee, Jun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2014.05a
    • /
    • pp.286-287
    • /
    • 2014
  • Performance degradation of Ultra High Strength Concrete occurs more than that of normal strength concrete at high temperature. Thus, strain of concrete subjected to high temperature and loading is one of the core assessment items for evaluating performance of structures. Therefore, in this study, creep of ultra high strength concrete subjected to various temperature conditions and 25%, 40% loading was evaluated. As the results, Creep strain increased with increase of temperature and loading. Creep strain of concrete at high temperature is influenced by loading.

  • PDF

Structural Design of an Ultra High-rise Building Using Concrete Filled Tubular Column with 780 N/㎟ Class High-strength Steel and Fc150 N/㎟ High-strength Concrete

  • Matsumoto, Shuichi;Hosozawa, Osamu;Narihara, Hiroyuki;Komuro, Tsutomu;Kawamoto, Shin-ichiro
    • International Journal of High-Rise Buildings
    • /
    • v.3 no.1
    • /
    • pp.73-79
    • /
    • 2014
  • In recent years, the performance requested for which an ultra-high rise buildings is diversified. Large spans are designed in order to gain wide workspace. Column positions are shifted in middle stories to provide space different from neighboring floors. Moreover, in the bottom layers of the building, it is becoming more important to expand freedom to plan flexibility such as creating publically opened wide atria that gives attractive free space. Earthquake-proof criteria is also changing not only human life protection deign but also a design that allows functional continuity. In order to achieve thee needs, as one of technology, we have developed ultra-high strength concrete filled tubular (CFT) columns of the box section that combine ultra-high strength concrete with specified strength of $150N/mm^2$ and ultra-high strength steel material with tensile strength of $780N/mm^2$. In this paper, the outline of development of an ultra-high strength CFT column is reported. Also, the structural design of the ultra-high-rise building using the CFT columns is reported.

A Study on the Manufacture and Application of Ultra-high Strength Concrete (초고강도 콘크리트의 제조 및 현장적용성에 관한 연구)

  • Choi, Il-Ho;Jung, Yang-Hee;Kim, Ook-Jong;Lee, Do-Bum
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2007.11a
    • /
    • pp.1-4
    • /
    • 2007
  • Because reinforced concrete structures were being high more and more in recent year, concrete was being demanded high performance of high strength and high fluidity. But various characteristics must be confirmed besides guarantee of demand strength in ultra-high strength concrete. In ultra-high strength concrete, autogenous shrinkage and drying shrinkage grow big because of a low water cement ratio and much quantity of binder. So dangerousness of crack generation grow big in early ages. And ultra-high strength concrete is influenced by use materials more than ordinary strength concrete. In this study we were examined mix design, atuogenous shrinkage and pumpability of ultra-high strength concrete to apply on the ground.

  • PDF

Sensitive Product Design of Ultra High Performance Concrete (UHPC) (감성 콘크리트 블루투스 스피커 (콩스) 제품 디자인)

  • Kim, Kyuong-Hwan;Kim, Byoung-Il
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2020.06a
    • /
    • pp.197-198
    • /
    • 2020
  • A study was conducted on UHPC production using the silicone mold method. UHPC (Ultra-High-Performance Concrete) has the advantage of being able to shape the product in a free-form shape on concrete, but when mass-producing products in one design, such as electronic products, rather than one-time products such as buildings and decorations Demolition is difficult with wood and mold. This study uses silicone molds, UHPC mix to ensure fluidity, self-integrating performance and mechanical performance Prototyping was done proportionally.

  • PDF

A Study on Fire Resistance Performance Evaluation for Field Application of Ultra-High Strength Concrete (초고강도 내화 콘크리트의 현장 적용을 위한 내화성능 평가에 관한 연구)

  • Baek, Young-Woon;Yuk, Tae-Won;Park, Dong-Soo;Kim, Han-Sol;Lee, Hang-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2023.11a
    • /
    • pp.41-42
    • /
    • 2023
  • The physical performance of high-strength concrete deteriorates when exposed to high temperatures such as fire. In particular, in the case of ultra-high-strength concrete, there is a high possibility of explosion due to internal water pressure and thermal expansion due to the tight internal structure. In this paper, a fire resistance certification test was conducted for field application of ultra-high-strength fire-resistant concrete, and the fire resistance performance (temperature rise of main rebar) was compared according to the structural concrete cover thickness. As a result, when the covering thickness was 40 mm, three structures did not meet the certification standards, and when the covering thickness was 50 mm, all structures met the fire resistance certification standards.

  • PDF

A Study for Application of 180 MPa Ultra High Performance Concrete to Compressive Members (180MPa 초고성능 콘크리트의 압축 부재에의 적용성에 대한 연구)

  • Min, Kyung-Hwan;Choi, Hong-Shik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.7
    • /
    • pp.4930-4935
    • /
    • 2015
  • In the actual research fields, the studies for applications of 180 MPa ultra high performance concrete (UHFRCC) to compressive members are limited due to its very high compressive strength. In this study, in order to find its practical use, UHPC was producted by using twin-shaft mixer batch plant. Also, to get basic research data for the design specification of UHPC compressive members, a series of draft experiments, including short columns with square and circular sections, were performed and its failure modes and behaviors were assessed.