• Title/Summary/Keyword: BASE

검색결과 23,330건 처리시간 0.041초

베이스 가진을 받는 전자기 베어링계의 베이스 가속도 피드포워드 제어 (Base Acceleration Feedforward Control For An Active Magnetic Bearing System Subject To Base Motion)

  • Kang, Min-Sig
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2002년도 추계학술대회논문초록집
    • /
    • pp.399.2-399
    • /
    • 2002
  • This paper concerns on a non-rotating single-DOF beam-active magnetic bearing(AMB) system subject to arbitrary shaped base motion. In such a system, it is desirable to retain the beam within the predetermined air-gap under foundation excitation. Motivated form this, an adaptive acceleration feedforward control is proposed to reduce the base motion response without deteriorating other feedback control performances. Experimental results demonstrate the effectiveness of the acceleration feedforward control.

  • PDF

WORLD WIDE BASE STOCK TRENDS

  • Henderson, H.E.
    • 한국윤활학회:학술대회논문집
    • /
    • 한국윤활학회 2002년도 the technical trends in the world automobile and lubricant market
    • /
    • pp.55-62
    • /
    • 2002
  • Significant changes in the performance requirements of finished lubricants is having a pronounced impact on the quality and manufacturing approach for base stocks, the building block for these products. Separation processing is no longer capable of producing high yields of premium base stocks and is rapidly being replaced with hydroprocessing. Isoparaffins are the most desirable component because of their high Viscosity Index, low pour point and excellent stability. This paper will discuss industry trends and the drive towards higher quality base stocks. Manufacturing options are discussed and examples presented to demonstrate the performance of these premium base stocks.

  • PDF

의치상(義齒床) 개선(改選)에 관한 연구(硏究) (A Study on the Improvement of Denture Base construction)

  • 신무학
    • 대한치과기공학회지
    • /
    • 제14권1호
    • /
    • pp.133-138
    • /
    • 1992
  • The base of a metal base denture that is made of acrylic resin base and metal in lined by soft liner named silicon rubber and its merits are as follows. 1. It has a good retention and fastness. 2. It has a good comfort and stability. 3. It is easy to mix various kinds of base materials. 4. It is easy to repair. 5. The pressure of bone and mucosal tissue is decreased and bite force is dispersed.

  • PDF

기초분리방법을 이용한 교량 내진 설계 (Seismic Design of Bridges Using Base Isolation)

  • 황의승
    • 전산구조공학
    • /
    • 제4권4호
    • /
    • pp.107-116
    • /
    • 1991
  • Base isolation is the alternative tool to protect structures against the earthquake. Basic ideas are the flexibflity to reduce the response of the structure, energy dissipation to reduce the excessive deflection by flexibility, and the rigidity under the service load. Base isolation is specially good for bridges because it can be installed easily and be used for both new construction and rehabilitation. This paper describes the basic ideas of base isolation, various base isolation devices and design guidelines by AASHTO. It also introduces the applications in United States and New Zealand.

  • PDF

CFD를 이용한 유도탄 power-on 기저항력 해석 (NUMERICAL SIMULATION OF THE POWER-ON BASE DRAG OF A MISSILE BODY)

  • 최재혁;이은석;이광섭
    • 한국전산유체공학회지
    • /
    • 제20권2호
    • /
    • pp.16-22
    • /
    • 2015
  • The pressure is generally lower than that of the freestream at the base of a missile body due to the energy loss by the flow separation around the edge of the base. The base pressure changes in the presence of the thrust jet due to the interaction between the base flow of the missile and the jet flow. In this study, behavior of the missile base pressure by the change of the jet exit pressure and the freestream condition is investigated using the CFD(Computational Fluid Dynamics) method. Effects of the grid type and the freestream condition are tested. The results are compared with the semi-empirical predictions and the flight test data. The CFD results agree well with the flight test data. The semi-empirical predictions overestimate the base pressure when jet thrust is strong for low freestream speed.

조림묘목 mulching mat 제조용 base paper의 물리적 특성 연구 (Studies on the Physical Properties of Base Paper for the Manufacture of Mulching Mat for Afforestation Seedling)

  • 김형진;오동근;유영정
    • 펄프종이기술
    • /
    • 제41권1호
    • /
    • pp.37-43
    • /
    • 2009
  • In this study, the physical properties of base paper for the manufacture of mulching mat for afforestation seedling were investigated. The base paper for mulching mat was prepared by stock conditions of PAE and AKD addition into the screened slurry of KOCC for the strengthening effects of wet tensile and burst strength. The optimum additions of PAE and AKD were considered at 2% and 0.5%, respectively. The accelerated aging by ISO 5630-1 and wet heat aging method under hot water for 2 kinds of commercial mulching and wet strength paper were compared with the base paper prepared for mulching mat manufacture. The accelerated aging test for the base paper prepared for mulching mat manufacture resulted in the same tendency of physical properties as two kinds of commercial products. However, the results of wet heat aging test under hot water indicated that the physical strength for base paper prepared was much higher than others. In addition, the opacity behavior for base paper prepared was enough effects to obstruct weeds growth by isolating transmission of sunlight.

커피에 의한 의치상 레진의 색 변화에 관한 연구 (THE COLOR CHANCE OF DENTURE BASE RESINS BY COFFEE)

  • 한상훈;동진근;진태호
    • 대한치과보철학회지
    • /
    • 제31권4호
    • /
    • pp.523-531
    • /
    • 1993
  • The purpose of this study was to investigate the color change of denture base resins by coffee. Denture base resins for this study were Triad VLG Denture Base (Dentsply, York Div. U.S.A.), Premium Super-20 (Lang Dental Mfg. Co., Inc., U.S.A.) for denture base, Toughron Rebase (Miki Chemical Prod., Kyoto, Japan), Jet Repair Acrylic (Lang Dental Mfg. Co., Inc., U.S.A.), Triad Reline (Dentsply, fork Div. U.S.A.) and Tokuso Rebase (Tokuyama Soda Co., Ltd., Japan) for denture rebase. Twenty specimens of each denture base resin were made and polished. The color of specimens was measured by colorimeter (Model Tc-6FX, Tokyo Denshoku Co. Japan), and they were stored in coffee for three weeks and then color changes were measured. The obtained results were as follows : 1. The L*, a*, b* and the E*ab values of all denture base resins were changed after three weeks. 2. The amount of color change on L*, a*, b* and the E*ab value of each specimens showed different patterns. 3. The b* values of Triad Reline materials were changed more than the other materials. 4. The E*ab values of Triad Denture Base materials were changed more than the other materials.

  • PDF

動力傳達용 齒車設計를 中心으로 한 機械要素 設計의 엑스퍼트 시스템 開發硏究 I (Development of Expert System for Designing Power Transmission Elements, Especially of Gear Drives (I) - Building and Operation of Data Base for Designing and Trouble-Shooting of Gear Drives -)

  • 정태형;구보애삼
    • 대한기계학회논문집
    • /
    • 제11권6호
    • /
    • pp.1014-1025
    • /
    • 1987
  • 본 연구에서는 기계요소중에서도 그 성능에 미치는 인자의 수가 많고 또 그 영향이 복잡하고 난해하며 아직도 경험적 요소가 수많이 남아있으면서도 공업적으로 매우 중요한 동력전달용 치차장치를 예로 들어 그 설계, 제작, 손상 및 트러블슈팅을 하기 위한 엑스퍼트시스템을 개발하려고 한다.

객체지향 데이터베이스를 이용한 지식베이스 모형(OOKS) 개발 (Development of OOKS : a Knowledge Base Model Using an Object-Oriented Database)

  • 허순영;김형민;양근우;최지윤
    • 지능정보연구
    • /
    • 제5권1호
    • /
    • pp.13-34
    • /
    • 1999
  • Building a knowledge base effectively has been an important research area in the expert systems field. A variety of approaches have been studied including rules, semantic networks, and frames to represent the knowledge base for expert systems. As the size and complexity of the knowledge base get larger and more complicated, the integration of knowledge based with database technology cecomes more important to process the large amount of data. However, relational database management systems show many limitations in handing the complicated human knowledge due to its simple two dimensional table structure. In this paper, we propose Object-Oriented Knowledge Store (OOKS), a knowledge base model on the basis of a frame sturcture using an object-oriented database. In the proposed model, managing rules for inferencing and facts about objects in one uniform structure, knowledge and data can be tightly coupled and the performance of reasoning can be improved. For building a knowledge base, a knowledge script file representing rules and facts is used and the script file is transferred into a frame structure in database systems. Specifically, designing a frame structure in the database model as it is, it can facilitate management and utilization of knowledge in expert systems. To test the appropriateness of the proposed knowledge base model, a prototype system has been developed using a commercial ODBMS called ObjectStore and C++ programming language.

  • PDF