• Title/Summary/Keyword: practically

Search Result 2,907, Processing Time 0.041 seconds

A Study on Non-Fragile Controller Design for Parameter Uncertain Systems (파라미터 불확실성 시스템에 대한 비약성 제어기 설계에 관한 연구)

  • 박성욱;오준호
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.272-272
    • /
    • 2000
  • since the controller is part or the overall closed-Loop system, it is necessary that the designed controller be able to tolerate some uncertainty in its coefficients. The adequate stability and performance margins are required for the designed nominal controllers. In the paper. we study the method to design the non-fragile fixed-structured controller for real parametric uncertain systems. When we impose the controller parameter perturbation, the structure of the controller must be given. Therefore, we assume that the controller has fixed-structure. The fixed-structure controller is practically necessary especially when the robust controller synthesis results in a high-order controller. In SISO systems, we propose the robust controller design method using the Mapping theorem. In the method, the plant uncertainty and controller Parameter are of the multilineal form in the stability and performance conditions. Then, the controller synthesis problem is easily recast to Linear Programming Problem.

  • PDF

Diagnosis and Integrated Management of Major Fungal Fruit Rots on Kiwifruit in Korea

  • Kim, Gyoung Hee;Koh, Young Jin
    • Research in Plant Disease
    • /
    • v.24 no.2
    • /
    • pp.113-122
    • /
    • 2018
  • Ripe rot, Botrytis storage rot and Sclerotinia rot are major fungal diseases that lead to deterioration of fruit quality in Korea. Ripe rot, which is caused by Botryosphaeria dothidea, affects harvested fruits during post-storage ripening, while Botrytis storage rot, caused by Botrytis cinerea, affects harvested fruits during cold storage, and Sclerotinia rot, caused by Sclerotinia sclerotiorum, mainly affects immature fruits on the trees. Major fungal fruit rots tend to affect yellow- and red-fleshed cultivars of kiwifruit more severely because of the sharp increase in their cultivation acreage in recent years in Korea. In this review, we summarize symptoms and epidemiological characteristics of the major fungal fruit rots and propose integrated management methods of the diseases that can be practically utilized at the farmers' orchards in order to prevent the diseases based on our research works and field experiences and the research works of others conducted during the last three decades worldwide.

Development of an Engineering Reading & Writing Textbook and Analysis of Study Outcomes (공학 Reading & Writing 교재 개발 및 학습성과 분석)

  • Chung, Ho-Yeon;Jun, Oh-Sung;Yoo, Kyu-Sun;Jang, Mi-Young
    • Journal of Engineering Education Research
    • /
    • v.14 no.6
    • /
    • pp.51-59
    • /
    • 2011
  • The authors have developed a reading & writing textbook for engineering students to improve their communication capability, and also analyzed the outcomes that the students accomplished through the Engineering Reading and Writing class. The reading & writing textbook has been organized to be used as a guidebook with which the engineering students can practically solve the problems that they would face continuously after they finish their regular curriculum and when they are employed. The questionnaire survey analysis has been performed in order to evaluate the textbook contents, lecturing, and learning outcomes for the lecturers and students finished the engineering reading and writing classes. Desirable evaluation has been resulted in the broad areas: subject extraction from the readings, logical understanding, summarizing, practical writing, writing principle, etc.

A Resetting Scheme for Process Parameters using the Mahalanobis-Taguchi System

  • Park, Chang-Soon
    • The Korean Journal of Applied Statistics
    • /
    • v.25 no.4
    • /
    • pp.589-603
    • /
    • 2012
  • Mahalanobis-Taguchi system(MTS) is a statistical tool for classifying the normal group and abnormal group in multivariate data structures. In addition to the classification itself, the MTS uses a method for selecting variables useful for the classification. This method can be used efficiently especially when the abnormal group data are scattered without a specific directionality. When the feedback adjustment procedure through the measurements of the process output for controlling process input variables is not practically possible, the reset procedure can be an alternative one. This article proposes a reset procedure using the MTS. Moreover, a method for identifying input variables to reset is also proposed by the use of the contribution. The identification of the root-cause parameters using the existing dimension-reduced contribution tends to be difficult due to the variety of correlation relationships of multivariate data structures. However, it became possible to provide an improved decision when used together with the location-centered contribution and the individual-parameter contribution.

퇴적물 내 비소의 지구미생물학적 거동 연구

  • Lee Jong-Un;Lee Sang-U;Park Ji-Min;Kim Gyeong-Ung;Jeon Hyo-Taek;Jeong Myeong-Chae
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2006.04a
    • /
    • pp.111-114
    • /
    • 2006
  • The effects of indigenous bacteria on geochemical behavior of As in As-contaminated sediments (Hwachon mine and Myoungbong mine) after biostimulation with a variety of carbon sources were investigated under anaerobic condition. In Hwachon sediment, As was dramatically extracted from nonsterile sediment with time, reaching the highest concentration of $500{\mu}g/L$. The As leaching was likely caused by microbial dissolution of Fe oxides/oxyhydroxides with which As had been coprecipitated. However, in the case of Myoungbong sediment supplied with glucose, dissolved As decreased with time likely due to production of As sulfide(s) and subsequent precipitation, which resulted from bacterial reduction of $SO_4^{2-}$. The results implied that bacterial in-situ stabilization of As In subsurface has a potential to be practically applied.

  • PDF

Slip Coefficients between Steel Plates Fixed with High Tension Bolts (고장력볼트로 체결되는 철판 사이의 미끄럼계수)

  • Kim, Choong-Hyun
    • Tribology and Lubricants
    • /
    • v.24 no.6
    • /
    • pp.338-342
    • /
    • 2008
  • Tensile test results using three kinds of steel structure specimens are measured and compared. Slip coefficient between shot blasted steel plates was greater than 0.6. For the case of the plates coated with Super zinc, it revealed that the coefficients were greater than 0.5. On the other hand, Super epoxy coating decreased its slip coefficient less than 0.25. Steel plates coated with Super zinc are proved to be practically applicable to the steel structures with anti-corrosion characteristics and clean surfaces.

Effects of Blank Design factors on Stretch Flange Forming of the Tailored Blank Using Taguchi Method (다구찌법을 이용한 테일러드 블랭크의 신장플랜지 성형에 미치는 설계 인자의 영향 분석)

  • 백승엽;권재욱;이경돈
    • Transactions of Materials Processing
    • /
    • v.9 no.4
    • /
    • pp.339-347
    • /
    • 2000
  • For the successful forming of tailored blank, it is important to control the deformation of the stretch flange mode, which is strong1y dependent upon the location of weld line and blank shape. In order to investigate the effects of tailored blank design factors on the stretch flange forming, we made the model die which can simulate stretch flange mode. Taguchi method was employed to analyze the sensitivity of blank design factors for the forming of tailored blank. From the results of experiment S/N ratios were calculated and using Variance Analysis, significance of parameters and optimal condition of each factors were extracted. Based on these analyses, the weld line height and the strength ratio and the arc center height were selected as effective parameter. The analysed result was practically applied for Side outer panel stamping process.

  • PDF

Development of Clinical Practice Guideline for Hwabyung (2) - Tools for Development - (화병 임상진료지침 개발 연구 (2) - 지침 개발에 활용되는 도구 -)

  • Chung, Sun-Yong;Kim, Jong-Woo
    • Journal of Oriental Neuropsychiatry
    • /
    • v.20 no.2
    • /
    • pp.153-162
    • /
    • 2009
  • Objectives : The approach to Hwabyung from all angles is needed to develop the clinical practice guideline. To achieve this approach, various tools should be used practically and systematically. Methods : We gather the tools based on multi aspects of Hwabyung's characteristics. The tools will be used to each steps of clinical practice guideline development. Results : For the clinical practice guideline, there should be applied many kinds of tools, such as for decision and assesment, survey with oriental medicine property, collecting individual stress information, mental and psychological trait, and related or following disease. Conclusions : Application of many objective tools provides the evidence-based medical approaches for development of clinical practice guideline for Hwabyung.

  • PDF

Shape Design of Guillotined Shear Cutters for Steel Pipes (강관의 Guillotine 전단날 형상 설계)

  • Cho Haeyong;Lee Sangmin;Lee Sungkil;Kim Yongyun
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.22 no.2
    • /
    • pp.105-112
    • /
    • 2005
  • The guillotined cutting process for the pipe was studied in this paper. Until now guillotining mechanism can not be practically applied in the industries because of the deformation of sheared section around cutting area, the coarse sheared surface, and the burs. To find optimum shapes of blade, several types of blade were experimentally studied. The cutting force normal to the axial direction of the pipe was compared with the theoretical result based on the cutting energy. The experimental maximum cutting forces were very good agreement with the theoretical results. It also discussed that the design parameters of guillotining system such as the blade shape and the clearance between the blade and the die made effects to the deformation of the cutting cross section area. The results show that the guillotining method can be applicable to the pipe cutting system by optimizing the blade shape and the clearance between the blade and the die of the guillotined cutting system with respect to the sheared pipe material.

A study on the Minimum-Time Path Decision of a Soccer Robot using the Variable Concentric Circle Method (가변 동심원 도법을 이용한 축구로봇의 최단시간 경로설정에 관한 연구)

  • Lee, Dong-Wook;Lee, Gui-Hyung
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.19 no.9
    • /
    • pp.142-150
    • /
    • 2002
  • This study describes a method of finding an optimal path of a soccer robot by using a concentric circle method with different radii of rotation. Comparing with conventional algorithms which try to find the shortest path length, the variable concentric circle method find the shortest moving time. The radius fur the shortest moving time for a given ball location depends on the relative location between a shooting robot and a ball. Practically it is difficult to find an analytical solution due to many unknowns. Assuming a radius of rotation within a possible range, total path moving time can be calculated by adding the times needed for straight path and circular path. Among these times the shortest time is obtained. In this paper, a graphical solution is presented such that the game ground is divided into 3 regions with a minimum, medium, and maximum radius of rotation.