• 제목/요약/키워드: Profile approach

검색결과 610건 처리시간 0.025초

유한 요소법을 이용한 다단패스 형상압연 공정 해석 (Analysis of Multi-Pass Shape Rolling Processes using Finite Element Method)

  • 김홍준;김태효;황상무
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
    • /
    • pp.69-77
    • /
    • 1999
  • Roll profile design in spape rolling with a complex-shaped part depends on the designer's experience, which is general, is acquired through costly trial-and-error process. As a prerequisite for developing a scientific approach to roll profile design, we present a finite element model to simulate 3-D deformation of complex-shaped parts occuring in multi-pass sequence. Demonstrated is the process model's capability to deal with rolling of a complex-shaped part.

  • PDF

Coordinated Wide-Area Regulation of Transmission System for Voltage Profile Improvement and Power Loss Reduction

  • Asadzadeh, Babak;Golshannavaz, Sajjad
    • Transactions on Electrical and Electronic Materials
    • /
    • 제18권5호
    • /
    • pp.279-286
    • /
    • 2017
  • In this paper, an optimal approach for the wide-area regulation of control devices in a transmission network is proposed. In order to realize an improved voltage profile and reduced power loss, existing devices such as tap-changing transformers, synchronous machines, and capacitor banks should be controlled in a coordinated and on-line manner. It is well-understood that phasor measurement units in transmission substations allow the system operators to access the on-line loading and operation status of the network. Accordingly, this study proposes efficient software applications that can be employed in area operation centers. Thus, the implanted control devices can be regulated in an on-line and wide-area coordinated approach. In this process, efficient objective functions are devised for both voltage profile improvement and power loss reduction. Subsequently, sensitivity analysis is carried out to determine the best weighting factors for these objectives. Extensive numerical studies are conducted on an IEEE 14-bus test system and a real-world system named the Azarbayjan Regional Transmission Network. The obtained results are discussed in detail to highlight the promising improvements.

Application of the Direct Displacement Based Design Methodology for Different Types of RC Structural Systems

  • Malekpour, Saleh;Dashti, Farhad
    • International Journal of Concrete Structures and Materials
    • /
    • 제7권2호
    • /
    • pp.135-153
    • /
    • 2013
  • This study investigates the direct displacement based design (DDBD) approach for different types of reinforced concrete structural systems including single moment-resisting, dual wall-frame and dual steel-braced systems. In this methodology, the displacement profile is calculated and the equivalent single degree of freedom system is then modeled considering the damping characteristics of each member. Having calculated the effective period and secant stiffness of the structure, the base shear is obtained, based on which the design process can be carried out. For each system three frames are designed using DDBD approach. The frames are then analyzed using nonlinear time-history analysis with 7 earthquake accelerograms and the damage index is investigated through lateral drift profile of the models. Results of the analyses and comparison of the nonlinear time-history analysis results indicate efficiency of the DDBD approach for different reinforced concrete structural systems.

A finite element based approach to observe hydrodynamic pressure in reservoir adjacent to concrete gravity dam

  • Santosh Kumar, Das;Kalyan Kumar, Mandal;Arup Guha, Niyogi
    • Ocean Systems Engineering
    • /
    • 제12권4호
    • /
    • pp.385-402
    • /
    • 2022
  • This paper deals with the study of hydrodynamic pressure in reservoir adjacent to the concrete gravity dam subjected to dynamic excitation. Widely famous finite element method is used to discretize the reservoir domain for modelling purpose. Pressure is considered as nodal variable following Eulerian approach. A suitable nonreflecting boundary condition is applied at truncated face of reservoir to make the infinite reservoir to finite one for saving the computational cost. Thorough studies have been done on generation of hydrodynamic pressure in reservoir with variation of different geometrical properties. Velocity profile and hydrodynamic pressure are observed due to harmonic excitation for variation of inclination angle of dam reservoir interface. Effect of bottom slope angle and inclined length of reservoir bottom on hydrodynamic pressure coefficient of reservoir are also observed. There is significant increase in hydrodynamic pressure and distinct changes in velocity profile of reservoir are noticeable for change in inclination angle of dam reservoir interface. Change of bottom slope and inclined length of reservoir bottom are also governing factor for variation of hydrodynamic pressure in reservoir subjected to dynamic excitation.

The Impact of Consumer Evaluation on the Cause-Related Marketing

  • Lee, Chia-Lin
    • Asia Marketing Journal
    • /
    • 제19권1호
    • /
    • pp.1-17
    • /
    • 2017
  • Cause-related Marketing (CrM) has become an increasingly popular marketing approach over the past two decades. However, neither researchers nor organizations fully understand the determinants of a successful CrM partnership. This research fills this gap. Specifically, we employ the schema theory to explore circumstances in which the CrM alliance cannot achieve a success. We use a theoretical modeling approach to report that, when consumers' typicality-based cognitive process is assumed, the CrM activity with the partners' more-discrepant attribute profile cannot be evaluated favorably, but the attribute-level uncertainty about the CrM alliance is less likely to feedback to the two partners. Furthermore, we argue that, under the schema-plus-tag model, consumers may not like the CrM program with a similar attribute profile. Therefore, this CrM approach may fail. To our knowledge, we are the first to apply the schema theory to explain how a CrM alliance can achieve a success.

자동항해를 지원하는 적응형 웹 서핑 시스템 (An Adaptive Web Surfing System for Supporting Autonomous Navigation)

  • 국형준
    • 한국정보과학회논문지:소프트웨어및응용
    • /
    • 제31권4호
    • /
    • pp.439-446
    • /
    • 2004
  • 사용자 적응형 웹 서핑 시스템 설계를 위해 전체 시스템을 사용자 데이타 수집, 데이타 처리를 통한 사용자 프로파일 구축 및 개선, 그리고 사용자 프로파일의 적용을 통한 적응 등 세 단계로 나누어 접근할 수 있다. 본 연구가 설계한 세 부문의 에이전트들은 이들 각 단계에서 작업하며 상호 유기적인 협동을 통해 적응형 웹 서핑을 지원한다. 이들은 각각 대화식 인터페이스 에이전트(Interactive Interface Agent), 사용자 프로파일 에이전트(User Profile Agent), 그리고 자동항해 에이전트(Autonomous Navigation Agent)이다. 대화식 인터페이스 에이전트는 사용자 인터페이스를 제공하며 이를 통해 데이타를 수집하고 기계적 항해 지원을 수행한다. 사용자 프로파일 에이전트는 수집된 사용자 데이타를 처리하여 사용자 브라우징의 실시간에 사용자 프로파일을 동적으로 구축하고 갱신한다. 자동항해 지원 에이전트는 사용자 프로파일에 기초하여 사용자 관심과 가까운 웹 문서를 자동으로 선별하여 추천하는 자동 항해 모드를 제공한다. 본 연구가 제시하는 접근과 설계 방식은 향후 확장과 보완을 통해 실용 가능한 수준의 사용자 적응형 웹 서핑 시스템 구축에 활용될 수 있다.

열간압연 공정에서 롤 프로파일 예측모델 향상 (Improvement of Roll Profile Prediction Model in Hot Strip Rolling)

  • 정제숙;유종우;박해두
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2007년도 춘계학술대회 논문집
    • /
    • pp.229-232
    • /
    • 2007
  • In hot strip rolling, the work roll profile is one of the main factors in predicting and correcting the strip profile. Various studies concerning the wear profile and the thermal crown of work roll have been performed, and the results of these studies have shown that the work roll profile must be predicted accurately so as to efficiently control the strip qualities such as thickness, crown, flatness, and camber. Therefore, a precise prediction model of roll profile is called for in a perfect shape control system. In this paper, a genetic algorithm was applied to improve on the roll profile prediction model in hot strip rolling. In this approach, the optimal design problem is formulated on the basis of a numerical model so as to cover the diverse design variables and objective functions. A genetic algorithm was adopted for conducting design iteration for optimization to determine the coefficient of the numerical model for minimization of errors in the result of the calculated value and the measured data. A comparative analysis showed a satisfactory conformity between them..

  • PDF

잔류진동 저감을 위한 비대칭 S-curve 프로파일의 영점 배치법 (Zero Placement of the Asymmetric S-curve Profile to Minimize the Residual Vibration)

  • 하창완;류근호;김경수;김수현
    • 제어로봇시스템학회논문지
    • /
    • 제18권4호
    • /
    • pp.308-313
    • /
    • 2012
  • Robust tuning rules of the motion profile are proposed to minimize the residual vibration. For asymmetric S-curve profile, tuning rules are analytically formulated using Laplace-domain approach. When the system modeling is known exactly, by placing a single zero of the motion profile on the pole of the system, the residual vibration can be perfectly eliminated under undamped system. However, if there are some amounts of the modeling errors, the residual vibration significantly increases. To track this issue, the robust tuning rules against modeling error are discussed. One of the proposed robust tuning rules is placing the multiple zeros of the motion profile on the pole of the system, and the other is placing the zeros of the motion profile around the pole of the system. Thanks to the proposed robust tuning rules, motion profile becomes more robust to modeling errors while minimizing the residual vibration. By simulation, the effectiveness of the proposed robust tuning rules is verified.

열간압연 공정에서 롤 프로파일 예측모델 향상 (Improvement of Roll Profile Prediction Model in Hot Strip Rolling)

  • 정제숙;유종우;박해두
    • 소성∙가공
    • /
    • 제16권4호
    • /
    • pp.250-253
    • /
    • 2007
  • In hot strip rolling, the work roll profile is one of the main factors in predicting and correcting the strip profile. Various studies concerning the wear profile and the thermal crown of work roll have been performed, and the results of these studies have shown that the work roll profile must be predicted accurately so as to efficiently control the strip qualities such as thickness, crown, flatness, and camber. Therefore, a precise prediction model of roll profile is called for in a perfect shape control system. In this paper, a genetic algorithm was applied to improve on the roll profile prediction model in hot strip rolling. In this approach, the optimal design problem is formulated on the basis of a numerical model so as to cover the diverse design variables and objective functions. A genetic algorithm was adopted for conducting design iteration for optimization to determine the coefficient of the numerical model for minimization of errors in the result of the calculated value and the measured data. A comparative analysis showed a satisfactory conformity between them.

A Study on the Fluorine Effect of Direct Contact Process in High-Doped Boron Phosphorus Silicate Glass (BPSG)

  • Kim, Hyung-Joon;Choi, Pyungho;Kim, Kwangsoo;Choi, Byoungdeog
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제13권6호
    • /
    • pp.662-667
    • /
    • 2013
  • The effect of fluorine ions, which can be reacted with boron in high-doped BPSG, is investigated on the contact sidewall wiggling profile in semiconductor process. In the semiconductor device, there are many contacts on $p^+/n^+$ source and drain region. However these types of wiggling profile is only observed at the $n^+$ contact region. As a result, we find that the type of plug implantation dopant can affect the sidewall wiggling profile of contact. By optimizing the proper fluorine gas flow rate, both the straight sidewall profile and the desired electrical characteristics can be obtained. In this paper, we propose a fundamental approach to improve the contact sidewall wiggling profile phenomena, which mostly appear in high-doped BPSG on next-generation DRAM products.