• Title/Summary/Keyword: base paper

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WORLD WIDE BASE STOCK TRENDS

  • Henderson, H.E.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10a
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    • pp.55-62
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    • 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.

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

  • 황의승
    • Computational Structural Engineering
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    • v.4 no.4
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    • pp.107-116
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    • 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.

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A Study on Implementation of 3D CAD Library for Injection Mold Base and Mold Components (사출금형 몰드베이스와 몰드 금형 부품의 3차원 CAD라이브러리 구축에 관한 연구)

  • Lee, Cheol-Soo;Park, Gwang-Ryeol;Kim, Yong-Hoon
    • IE interfaces
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    • v.12 no.3
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    • pp.480-486
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    • 1999
  • Mold base design is one of the most critical steps in production of plastic parts. This paper presents an efficient method for generating a 3D CAD library for injection mold base and mold components. In this paper, a new description language (DL)formats are proposed. These DL formats can represent the geometric feature, the variable dimensions and the assembly structures of mold base and its components. And the processes of adding the mold components and creating the mold assemblies can be performed very easily and efficiently by using DL scripts. Proposed method has been tested by implementation of 3D library with DL scripts and DL-interpreter with C language. The DL and interpreter are independent of CAD system. They were applied to the automatic mold base designing system which works on Unigraphics V15. The system is developed with UG API function under Windows-NT environment.

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A study on the Base Plate to reduce vibration for Refrigerator (Base Plate 연구를 통한 냉장고 진동 저감 방안 고찰)

  • Kim, Jung-Seon;Thuy, Tran Ho Vinh;Kook, Jung-Hwan;Wang, Se-Myung;Lee, Dong-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.340-343
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    • 2007
  • In this paper, we present our method to reduce vibration of the base plate of a refrigerator by avoiding resonance between base plate and compressor operation. To verify the modes of the base plate, FE models of the base plate with free-free condition and applied boundary condition were built and validated by results from experimental modal analysis. Operating Deflection Shape analysis was applied to find the sensitive area on the base plate during compressor operation. In optimization process, Finite Difference Method - based sensitivity analysis is used to detect the most sensitive area. Finally, based on this numerical result, we will make beads on the base plate to reduce vibration of refrigerator.

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Modeling and Countermeasure for Positioning Stage Base Vibration (위치결정 스테이지 베이스 진동 모델링 및 저감기법 개발)

  • Park, Ah-Yeong;Lim, Jae-Gon;Hong, Seong-Wook
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.19 no.4
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    • pp.476-484
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    • 2010
  • Precise positioning stages are often employed for precise machinery. For the purpose of vibration isolation, these precise positioning stages are mounted on a heavy base structure which is supported by compliant springs. Then the base structure is subjected to residual vibration due to the reactive force and vertical moving load induced by the stage motion. This paper investigates the vibration behavior of a positioning stage base and the associated vibration suppression technique. A dynamic model is developed to investigate the base vibration due to the reactive force and moving load effects by the moving stage. An input shaping technique is also developed to suppress the residual vibrations in base structures. Simulations and experiments show that the developed dynamic model adequately represents the base vibration and that the proposed input shaping technique effectively removes the residual vibrations from the positioning stage base.

Real-time hybrid substructuring of a base isolated building considering robust stability and performance analysis

  • Avci, Muammer;Botelho, Rui M.;Christenson, Richard
    • Smart Structures and Systems
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    • v.25 no.2
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    • pp.155-167
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    • 2020
  • This paper demonstrates a real-time hybrid substructuring (RTHS) shake table test to evaluate the seismic performance of a base isolated building. Since RTHS involves a feedback loop in the test implementation, the frequency dependent magnitude and inherent time delay of the actuator dynamics can introduce inaccuracy and instability. The paper presents a robust stability and performance analysis method for the RTHS test. The robust stability method involves casting the actuator dynamics as a multiplicative uncertainty and applying the small gain theorem to derive the sufficient conditions for robust stability and performance. The attractive feature of this robust stability and performance analysis method is that it accommodates linearized modeled or measured frequency response functions for both the physical substructure and actuator dynamics. Significant experimental research has been conducted on base isolators and dampers toward developing high fidelity numerical models. Shake table testing, where the building superstructure is tested while the isolation layer is numerically modeled, can allow for a range of isolation strategies to be examined for a single shake table experiment. Further, recent concerns in base isolation for long period, long duration earthquakes necessitate adding damping at the isolation layer, which can allow higher frequency energy to be transmitted into the superstructure and can result in damage to structural and nonstructural components that can be difficult to numerically model and accurately predict. As such, physical testing of the superstructure while numerically modeling the isolation layer may be desired. The RTHS approach has been previously proposed for base isolated buildings, however, to date it has not been conducted on a base isolated structure isolated at the ground level and where the isolation layer itself is numerically simulated. This configuration provides multiple challenges in the RTHS stability associated with higher physical substructure frequencies and a low numerical to physical mass ratio. This paper demonstrates a base isolated RTHS test and the robust stability and performance analysis necessary to ensure the stability and accuracy. The tests consist of a scaled idealized 4-story superstructure building model placed directly onto a shake table and the isolation layer simulated in MATLAB/Simulink using a dSpace real-time controller.

The method of using database technology to process rules of Rule-Based System

  • Zheng, Baowei;Yeo, Jeong-Mo
    • Journal of information and communication convergence engineering
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    • v.8 no.1
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    • pp.89-94
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    • 2010
  • The most important of rule-base system is the knowledge base that determines the power of rule-base system. The important form of this knowledge is how to descript kinds of rules. The Rule-Base System (RBS) has been using in many field that need reflect quickly change of business rules in management system. As far, when develop the Rule-Based System, we must make a rule engine with a general language. There are three disadvantage of in this developed method. First, while there are many data that must be processed in the system, the speed of processing data will become very slow so that we cannot accept it. Second, we cannot change the current system to make it adaptive to changes of business rules as quickly as possible. Third, large data make the rule engine become very complex. Therefore, in this paper, we propose the two important methods of raising efficiency of Rule-Base System. The first method refers to using the Relational database technology to process the rules of the Rule-Base System, the second method refers to a algorithm of according to Quine McCluskey formula compress the rows of rule table. Because the expressive languages of rule are still remaining many problems, we will introduce a new expressive language, which is Rule-Base Data Model short as RBDM in this paper.

Positioning of Wireless Base Station using Location-Based RSRP Measurement

  • Cho, Seong Yun;Kang, Chang Ho
    • Journal of Positioning, Navigation, and Timing
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    • v.8 no.4
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    • pp.183-192
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    • 2019
  • In fingerprint-based wireless positioning, it is necessary to establish a DB of the unmeasured area. To this end, a method of estimating the position of a base station based on a signal propagation model, and a method of estimating the information of the received signal in the unmeasured area based on the estimated position of the base station have been investigating. The purpose of this paper is to estimate the position of the base station using the measured information and to analyze the performance of the positioning. Vehicles equipped with a GPS receiver and signal measuring equipment travel the service area and acquire location-based Reference Signal Received Power (RSRP) measurements. We propose a method of estimating the position of the base station using the measured information. And the performance of the proposed method is analyzed on a simulation basis. The simulation results confirm that the accuracy of the positioning is affected by the measured area and the Dilution of Precision (DOP), the accuracy of the position information obtained by the GPS receiver, and the errors of the signal included in the RSRP. Based on the results of this paper, we can expect that the position of the base station can be estimated and the DB of the unmeasured area can be constructed based on the estimated position of the base stations and the signal propagation model.

Traffic analysis of the CDMA base station with repeaters using time delay devices (CDMA 시스템에서 Time Delay를 이용한 기지국과 중계기 Traffic 분석)

  • 조웅호;진용옥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.9A
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    • pp.1348-1358
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    • 2000
  • The paper contributes to a traffic analysis for the CDMA cellular base station with repeater which are operated in a cell site. Usually the repeaters' traffic of the CDMA cellular system hardly could be separated from that of the base station because the links of the repeaters are divided from RF circuits of the base station. The paper introduces a traffic measuring method that separates the traffic of repeaters from that of the base station using time delay device. To get general results we use a single BTS(Base station Transceiver Subsystem) with three repeater as well as a single BTS with a single repeater. Then we proved that the traffic of the repeaters could separate from that of the base station clearly.

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Design of Grid Accounting System based on Policy (정책 기반 Grid Accounting System 설계)

  • 장경익;허영선;황호전;김법균;곽의종;장행진;안동언;정성종
    • Proceedings of the IEEK Conference
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    • 2002.06c
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    • pp.115-118
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    • 2002
  • This paper designs Accounting structure for local users to policy base in Grid environment that integrate distributed Supercomputing resources geographically. Policy base virtual user Accounting system controls unnecessary increase of discrete Computing each local Accounting information. Also, This paper described method to manage do resources of each local system to policy base and presented way to process expense cost when used resources.

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