• Title/Summary/Keyword: Direct Response

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A study on the treatment of a max-value cost function in parametric optimization (매개변수 종속 최적화에서 최대치형 목적함수 처리에 관한 연구)

  • Kim, Min-Soo;Choi, Dong-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.10
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    • pp.1561-1570
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    • 1997
  • This study explores the treatment of the max-value cost function over a parameter interval in parametric optimization. To avoid the computational burden of the transformation treatment using an artificial variable, a direct treatment of the original max-value cost function is proposed. It is theoretically shown that the transformation treatment results in demanding an additional equality constraint of dual variables as a part of the Kuhn-Tucker necessary conditions. Also, it is demonstrated that the usability and feasibility conditions on the search direction of the transformation treatment retard convergence rate. To investigate numerical performances of both treatments, typical optimization algorithms in ADS are employed to solve a min-max steady-state response optimization. All the algorithm tested reveal that the suggested direct treatment is more efficient and stable than the transformation treatment. Also, the better performing of the direct treatment over the transformation treatment is clearly shown by constrasting the convergence paths in the design space of the sample problem. Six min-max transient response optimization problems are also solved by using both treatments, and the comparisons of the results confirm that the performances of the direct treatment is better than those of the tranformation treatment.

Fit Analysis for Men's Bodice Pattern Using 3D Scans -Compared to Traditional Fit Evaluation- (3차원 바디 스캐너를 이용한 남성 상의 원형의 피트성 평가 -직접평가와의 비교-)

  • Paek, Kyung-Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.1
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    • pp.139-148
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    • 2009
  • In this study, we tried to verify the effectiveness of 3D scans of clothed participants from 20 to 24 year old men in fit analysis process. Carrying out fit analysis, we used 3D scan data and direct fit evaluation with the basic garments made as semi-fitted bodice pattern for men. The result of fit evaluation through 3D scan data showed the expert rated fitting items more positive than direct fit evaluation. Even though, generally there was a no significant difference in the response between 3D and direct fit analysis. Only there was a significant difference in the response to the specific place such as the center front line, neckline, shoulder seam, and etc. There was a no significant difference between the result of 3D scan and direct fit evaluation in the subjects' group. Also the result of assessment of 3D targeting consumers showed very positive and interested in using 3D scans for fit analysis. The ability to rotate the 3D scans for a variety of views proved to be a very effective process to analyze fit. Moreover, digital data is easily accessed at any locations and any time. Fit analysis using 3D scans could be great tool for not only fit evaluation in research but also better fitting in apparel industry.

Effect of Aspect Ratio on Direct Tensile Response of Strain Hardening Cement Composites with PET and PVA Fiber (PET 및 PVA섬유를 사용한 변형경화형 시멘트 복합체의 직접인장거동에서 섬유 형상비의 영향)

  • Jeon, Esther;Yun, Hyun-Do;Park, Wan-Shin;Kim, Yong-Chul;Kim, Yun-Su
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.913-916
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    • 2008
  • Direct tensile response of strain hardening cement composites(SHCC) depends primarily on the material's tensile response, which is a water cement ratio, direct function of fiber and matrix characteristics, the bond between them, and the fiber volume fraction. This paper discusses effect of aspect ratio of the direct tensile response of SHCC with PET and PVA fibers. The main variables considered include the aspect ratio of PET fibers(Aspect ratio, ${\ell}/d_f$ : 150, 300, 600). For the same mixture proportion, PET1.5+PVA0.5-300 and PET1.5+PVA 0.5-600(Aspect ratio 300, 600) showed better overall behavior(Pseudo strain-hardening, Multiple cracking) than specimens with PET1.5+PVA0.5-150(Aspect ratio 150). Tensile strain of PET1.5+PVA0.5-300 and PET1.5+PVA 0.5-600 at ultimate tensile stress were 0.5, 2.0% respectively.

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Establishment of the roof model and optimization of the working face length in top coal caving mining

  • Chang-Xiang Wang;Qing-Heng Gu;Meng Zhang;Cheng-Yang Jia;Bao-Liang Zhang;Jian-Hang Wang
    • Geomechanics and Engineering
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    • v.36 no.5
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    • pp.427-440
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    • 2024
  • This study concentrates on the 301 comprehensive caving working face, notable for its considerable mining height. The roof model is established by integrating prior geological data and the latest borehole rock stratum's physical and mechanical parameters. This comprehensive approach enables the determination of lithology, thickness, and mechanical properties of the roof within 50 m of the primary mining coal seam. Utilizing the transfer rock beam theory and incorporating mining pressure monitoring data, the study delves into the geometric parameters of the direct roof, basic roof movement, and roof pressure during the initial mining process of the 301 comprehensive caving working face. The direct roof of the mining working face is stratified into upper and lower sections. The lower direct roof consists of 6.0 m thick coarse sandstone, while the upper direct roof comprises 9.2 m coarse sandstone, 2.6 m sandy mudstone, and 2.8 m medium sandstone. The basic roof stratum, totaling 22.1 m in thickness, includes layers such as silty sand, medium sandstone, sandy mudstone, and coal. The first pressure step of the basic roof is 61.6 m, with theoretical research indicating a maximum roof pressure of 1.62 MPa during periodic pressure. Extensive simulations and analyses of roof subsidence and advanced abutment pressure under varying working face lengths. Optimal roof control effect is observed when the mining face length falls within the range of 140 m-155 m. This study holds significance as it optimizes the working face length in thick coal seams, enhancing safety and efficiency in coal mining operations.

The chemical reactivity of detecting tube detection equipment for incident responder (화학사고 초기대응자를 위한 검지관식 탐지장비의 반응성 연구)

  • Ahn, Seung-Young;Kim, Jungmin;Kim, Sungbum;Chun, Kwangsoo;Lee, Jin-Seon;Park, Choonhwa
    • Journal of the Society of Disaster Information
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    • v.10 no.1
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    • pp.33-39
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    • 2014
  • Chemical accidents are the cause of the accident site during the initial responders to quickly and easily see materials and concentration method for the U.S. Environmental Protection Agency(EPA) is widely used in the initial response team direct reading detection equipment used. Ministry of the tubular gas detection equipment to detect direct reading detection equipment used in the event of an accident scene, and shell-and-tube gas detector for rapid detection and identification and precise analysis of causative pollutants before about strategically can identify the quantitative and qualitative useful equipment. However, those who initially respond to the scene of a direct reading detection equipment and a simple lack of understanding of how to use the numbers only because of the way you want to check the accuracy of detection results have been raising questions about the increase. The scene of the accident in order to obtain an accurate detection results used in this paper, the Ministry of Environment of gas detectors detect tubular Kitagawa and Draeger detector tube to check the reactivity of the material on-site detection of early response of those who were to raise the accuracy of the results.

A Direct Torque Control System for Reluctance Synchronous Motor Using Neural Network (신경회로망을 이용한 동기 릴럭턴스 전동기의 직접토크제어 시스템)

  • Kim, Min-Huei
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.1
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    • pp.20-29
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    • 2005
  • This paper presents an implementation of efficiency optimization of reluctance synchronous motor (RSM) using a neural network (NN) with a direct torque control (DTC). The equipment circuit considered with iron losses in RSM is analyzed theoretically, and the optimal current ratio between torque current and exiting current component are derived analytically. For the RSM driver, torque dynamic can be maintained with DTC using TMS320F2812 DSP Controller even with controlling the flux level because a torque is directly proportional to the stator current unlike induction motor. In order to drive RSM at maximum efficiency and good dynamics response, the Backpropagation Neural Network is adapted. The experimental results are presented to validate the applicability of the proposed method. The developed control system show high efficiency and good dynamic response features with 1.0 [kW] RSM having 2.57 inductance ratio of d/q.

Selection Responses for Milk, Fat and Protein Yields in Zimbabwean Holstein Cattle

  • Mandizha, S.;Makuza, S.M.;Mhlanga, F.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.7
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    • pp.883-887
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    • 2000
  • One way of evaluating the effectiveness of a dairy breeding program is to measure response to selection. This may be direct or indirect. The objectives of this study were to estimate expected progress for direct selection on milk, fat and protein yields; to estimate the expected correlated responses on indirect selection for milk, fat and protein yields in Zimbabwean Holstein cattle and to establish the effect of selection intensity on responses. The Animal Model contained fixed effects of herd, year of calving, calving month, dry period, milking frequency and additive effects pertaining to cows, sires and dams. AIREML software package was used to analyse the data. The genetic and phenotypic parameters obtained in this study were used to compute direct and correlated responses to selection. Because of the higher heritabilities in first parity, genetic progress was found to be greater when selection was practised on first parity cows as compared to later lactations. It is therefore recommended that older cows in the herd be replaced with improved heifers so as to enhance genetic progress.

A Direct Injection-mixing Total-flow-control Boom Sprayer System (주입식 총유량 자동제어방식 분관 방제기의 개발)

  • 구영모
    • Journal of Biosystems Engineering
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    • v.21 no.2
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    • pp.155-166
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    • 1996
  • A direct injection sprayer was designed using the concepts of injection mixing and total flow control, flowrate-based system compensating for the variation of forwarding speed. A metered rate, proportionally to the actual diluent flow rate, of a tracer chemical was injected directly into the diluent stream. The injection of chemical may improve the precision and safety of chemical application process. The control system was evaluated for the variables of the control interval, tolerances and sensitivities of flow regulation valve and injection pump. Performance of the system was assessed as that the response time of flow rate, response time of injection rate, absolute steady state error, and the coefficient of variance(C.V.) of concentration were 8.5 and -0.53 seconds, 0.067 lpm(0.8%) and 3.15%, respectively, at optimal parameters of control interval of 1.0 sec, fast sensitivity of flow regulation valve, medium sensitivity of injection pump and medium tolerance of flow rate. Performance of the system can be improved by increasing the sensitivity of flow regulating valve and employing a high resolution velocimeter, such as Doppler radar.

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Study for the Controller Design of a Direct Drive Servo Valve (직접구동형 서보밸브의 제어기 설계에 관한 연구)

  • 이성래;김종열;김치붕
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.136-136
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    • 2000
  • The direct drive servo valve(DDV) is composed of a DC rotor, link, valve spool and displacement sensor(LVDT) where the spool is directly coupled to the DC motor through the link. Since the DDV is a kind of one-stage valve, the robust controller is required to overcome the flow force effect on the spool motion. The mathematical equations are derived and the stability, accuracy and response speed of a DDV are investigated analytically using a linearized system block diagram. Proportional control, PID control. Time-Delay control, Sliding Mode control, and Proportional control using the load pressure are applied to DDV to find which one shows the best control performance. The digital computer simulation results show that the proportional control using the load pressure satisfies the design requirement of response speed and steady state error regardless of the variation of load pressure,

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Transient Response Analysis of Frame Structures Using the Finite Element-transfer Stiffness Coefficient Method (FE-TSCM) (유한요소-전달강성계수법을 이용한 골조 구조물의 과도응답해석)

  • 최명수;문덕홍;김성진
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.9
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    • pp.674-684
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    • 2002
  • In order to decrease remarkably the computation time and storage used in the direct integration method without the loss of accuracy, authors suggest a new transient analysis algorithm. This algorithm is derived from the combination of three techniques, that is, the transfer technique of the transfer stiffness coefficient method, the modeling technique of the finite element method, and the numerical integration technique of the Newmark method. In this paper, the transient analysis algorithm of a frame structure is formulated by the proposed method. The accuracy and computation efficiency of the proposed method are demonstrated through the comparing with the computation results by the direct integration method for three computation models under various excitations.