• Title/Summary/Keyword: D-efficient designs

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Robust Designs of the Second Order Response Surface Model in a Mixture (2차 혼합물 반응표면 모형에서의 강건한 실험 설계)

  • Lim, Yong-Bin
    • The Korean Journal of Applied Statistics
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    • v.20 no.2
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    • pp.267-280
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    • 2007
  • Various single-valued design optimality criteria such as D-, G-, and V-optimality are used often in constructing optimal experimental designs for mixture experiments in a constrained region R where lower and upper bound constraints are imposed on the ingredients proportions. Even though they are optimal in the strict sense of particular optimality criterion used, it is known that their performance is unsatisfactory with respect to the prediction capability over a constrained region. (Vining et at., 1993; Khuri et at., 1999) We assume the quadratic polynomial model as the mixture response surface model and are interested in finding efficient designs in the constrained design space for a mixture. In this paper, we make an expanded list of candidate design points by adding interior points to the extreme vertices, edge midpoints, constrained face centroids and the overall centroid. Then, we want to propose a robust design with respect to D-optimality, G-optimality, V-optimality and distance-based U-optimality. Comparing scaled prediction variance quantile plots (SPVQP) of robust designs with that of recommended designs in Khuri et al. (1999) and Vining et al. (1993) in the well-known examples of a four-component fertilizer experiment as well as McLean and Anderson's Railroad Flare Experiment, robust designs turned out to be superior to those recommended designs.

Monitoring of Clinical Trials: Issues and Recammendations

  • Fleming Thomas R.;Demets David L.
    • 대한예방의학회:학술대회논문집
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    • 1994.02b
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    • pp.270-284
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    • 1994
  • Interim analyses of randomized trials enable investigators to make more efficient use of limited research resources and to satisfy ethical requirements that a regimen be discontinued as soon as it has been established to have an inferior efficacy/toxicity profile. Unfortunately. the integrity and credibility of these trials can be compromised if inappropriate procedures are used in monitoring interim data. 'In this paper we discuss how group sequential designs provide useful guidelines that enable one to satisfy the valid objectives of interim monitoring while avoiding undesirable consequences, and we consider how flexible one can be in the way such designs are implemented. We also provide motivation for the role of data-monitoring committees in preserving study integrity and credibility in either government- or industry-sponsored trials. In our view. these committees should have multidisciplinary representation and membership limited to individuals free of apparent significant conflict of interest, and ideally should be the only individuals to whom the data analysis center provides interim results on relative efficacy of treatment regimens. Finally. we discuss some important practical issues such as estimation following group sequential testing, anal ysis of secondary outcomes after using a group sequential design applied to a primary outcome, early stopping of negative trials. and the role of administrative analyses.

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A Study of 3D Digital Fashion Design Using Kazmir Malevich's Formative Elements as AI Prompt (카지미르 말레비치의 조형적 요소를 AI 프롬프트로 활용한 3D 디지털 패션디자인 연구)

  • Jooyoung Lee
    • Journal of Fashion Business
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    • v.28 no.3
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    • pp.122-139
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    • 2024
  • Image-generated AI is rapidly emerging as a powerful tool to augment human creativity and transform the art and design process through deep learning capabilities. The purpose of this study was to propose and demonstrate the feasibility of a new design development method that combined traditional design methods and technology by constructing image-generated AI prompts based on artists' formative elements. The study methodology consisted of analyzing Kazmir Malevich's theoretical considerations and applying them to AI prompts for design, print pattern development, and 3D digital design. This study found that the suprematist works of Kazmir Malevich were suitable as design and print pattern prompts due to their clear geometric shapes, colors, and spatial arrangement. The AI-prompted designs and print patterns produced diverse results quickly and enabled an efficient design process compared to traditional methods, although additional refinement was required to perfect the details. The AI-generated designs were successfully produced as 3D garments, thereby demonstrating that AI technology could significantly contribute to fashion design through its integration with artistic principles. This study has academic significance in that it proposes a prompt composition method applicable to fashion design by combining AI and artistic elements. It also has industrial significance in that it contributes to design innovation and the implementation of creative ideas by presenting an AI-based design process that can be practically applied.

Reductions in the Cost and Risk of Interior Construction Using 3D CG Design (3차원 CG설계를 이용한 실내건축공사의 원가 및 리스크 절감)

  • Lee, Jun-Seob;Bang, Hong-Soon;Kim, Ok-Kyue
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.285-286
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    • 2021
  • These days, interior construction is performed to prevent the deterioration of old building finishings or to make distinctive designs. In case of interior construction, a construction cost is estimated through basic 2D drawings in the design step. Accordingly, an efficient construction plan and direction is established according to budget. In such a case, construction is dependent on 2D drawings. At that time, a risk can occur easily. This study is aimed at reducing the cost and risk of interior construction by implementing 3D drawings with the use of the visual data of 2D drawings. For accurate analysis, 2D drawings were completed, and then 3D interior construction modeling for various buildings was conducted with the 3D modeling software 3D Max. According to the 3D modeling, it reduced the cost and risk more than 2D drawings based design, and influenced the improvement in the understanding of orderers and workers.

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Development of High-Definition PDP TV with High-Efficient Hexagonal Array Structure

  • Lee, Byung-Hak;Heo, Eun-Gi;Yoon, Cha-Keun;Lee, Kwang-Sik;Cho, Yoon-Hyoung;Yoo, Min-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.347-350
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    • 2003
  • Optimization of the luminance, luminous efficiency, and address voltage margin characteristics has been made on the delta color array PDP with various hexagonal shape subpixels. The optimal subpixel and electrode designs are obtained for the 42-inch high-definition PDP ($1,366{\times}768$) with the fine pixel pitch less than 0.7 mm. The hexagonal delta array structure shows more improved characteristics than that of the normal delta array structure with rectangular shape subpixels.

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APPLICATION OF VISUALLISP PROGRAMMING LANGUAGE TO 3D SLUICE MODELING

  • Nguyen Thi Lan Truc;Po-Han Chen
    • International conference on construction engineering and project management
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    • 2007.03a
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    • pp.337-345
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    • 2007
  • Nowadays, it is convenient to use 3D modeling tools for general planning before construction. Normally, a 3D model is built with 3D CAD such as 3D Studio Max, Maya, etc. or simply with AutoCAD. All these software packages are effective in building 3D models but difficult to use, because many provided functions and tools require prior knowledge to build both 2D and 3D designs. Moreover, the traditional method of building 3D models is most time-consuming as experienced operators and manual input are required. Therefore, how to minimize the building time of 3D models and provide easy-to-use functions for users who are not familiar with 3D modeling becomes important. In this paper, the VisualLISP programming language is used to create a convenient tool for efficient generation of 3D components for the AutoCAD environment. This tool will be demonstrated with the generation of a 3D sluice, an artificial passage for water fitted with a valve or gate to stop or regulate water flow. With the tool, users only need to enter the parameters of a sluice in the edit box and the 3D model will be automatically generated in a few seconds. By changing parameters in the edit box and pressing the "OK" button, a new 3D sluice model will be generated in a short while.

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Efficient Approximation Method for Constructing Quadratic Response Surface Model

  • Park, Dong-Hoon;Hong, Kyung-Jin;Kim, Min-Soo
    • Journal of Mechanical Science and Technology
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    • v.15 no.7
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    • pp.876-888
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    • 2001
  • For a large scaled optimization based on response surface methods, an efficient quadratic approximation method is presented in the context of the trust region model management strategy. If the number of design variables is η, the proposed method requires only 2η+1 design points for one approximation, which are a center point and tow additional axial points within a systematically adjusted trust region. These design points are used to uniquely determine the main effect terms such as the linear and quadratic regression coefficients. A quasi-Newton formula then uses these linear and quadratic coefficients to progressively update the two-factor interaction effect terms as the sequential approximate optimization progresses. In order to show the numerical performance of the proposed method, a typical unconstrained optimization problem and two dynamic response optimization problems with multiple objective are solved. Finally, their optimization results compared with those of the central composite designs (CCD) or the over-determined D-optimality criterion show that the proposed method gives more efficient results than others.

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Comparative Studies on the Structural Design of Double Hull Tanker and Mid-deck Tanker (이중 선각 유조선과 중간 갑판 유조선의 구조설계 비교 연구)

  • Seung-Soo Na;Jae-Seon Yum
    • Journal of the Society of Naval Architects of Korea
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    • v.37 no.2
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    • pp.100-108
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    • 2000
  • As U.S. congress and I.M.O. have recently adopted strengthened MARPOL73/78 regulations on marine pollution, it is necessary to develope a new type of tankers such as Double hull tanker(D/H Tanker) and Mid-deck tanker(M/D Tanker) and so on. Because most of researches are concentrated on the volume of oil spill due to collision of ships, in this paper, a structural design program for D/H Tankers and M/D Tankers is developed to suggest the effective type of tankers by comparing structural characteristics between their types. By this program, minimum hull weight designs of D/H tankers and M/D tankers considering tank arrangement are performed and the design results are compared each other. The efficient types of hull structure for the minimum weight design between D/H tankers and M/D tankers is proposed.

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An Efficient Design of a DC-Block Band Pass Filter for the L-Band

  • Kaur, Avneet;Malhotra, Jyoteesh
    • Transactions on Electrical and Electronic Materials
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    • v.18 no.2
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    • pp.62-65
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    • 2017
  • In this paper, three DC Block designs are presented which efficiently meet the need of modern-day compactsize wireless communication systems. As one of the important parts of a complete system design, the proposed microstrip-based DC block with coupled transmission lines efficiently attenuates unwanted frequencies that cause damage to the system. The compact-sized DC block structures are created by incorporating an extended coupled-line section with a radial stub, an enveloped coupled-line section, and using alternate up-down meandering techniques. The structures are analyzed for the L-Band using a high-resistive silicon substrate. At a resonating frequency of 1.575 GHz, the designed DC Block structures have a return loss better than -10 dB, an insertion loss of around -1 dB, and also possess wide pass-band characteristics.

Structural Safety Evaluation of Hydraulic Steering System for Ship (선박용 유압 조타 시스템의 구조적 안전성 평가)

  • Lee, Moonhee;Son, Insoo;Yang, Changgun
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.4_2
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    • pp.661-667
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    • 2020
  • The optimal shape modeling of core parts through 3D modeling and structural analysis for the development of small and medium-sized ships. The goal is to improve the efficient structure of the hydraulic system for controlling the rudder among the core steering parts in small and medium-sized ships. Through 3D modeling and structural analysis, a new concept of tiller parts and a double-acting hydraulic cylinder control system were proposed and operational structural stability was evaluated. Structural analysis of the three different tiller designs that can be replaceable onto existing fishing vessels was conducted to derive the final shapes. The emphasis was placed on evaluating the structural stability of the key drive components, the tiller, pin, and cylinder rodin the maximum torque condition of the hydraulic cylinder.