• Title/Summary/Keyword: Master Model

Search Result 641, Processing Time 0.023 seconds

A STUDY ON THE ACCURACY OF DENTAL CAST AND DIE MATERIALS USING PHOTO-SCANNING (사진 주사(走査)를 이용한 치과용 모형재의 정확도에 관한 연구)

  • Yang, Seong-Wook;Lim, Ju-Hwan;Cho, In-Ho
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.34 no.2
    • /
    • pp.320-334
    • /
    • 1996
  • Dental cast and die materials are essential material using in almost dental prsthodontic procedure and it's most important requirement is accuracy for reqorducing the oral anatomical structures. In this study, 5 abutments A, B, C, D, E were fabricated on the metal master model to simulate the arch form and specimens were poured with 4 cast materials. Inter-abutment distances, A-B, A-C, A-D, A-E, B-C, B-D were calculated using the photo-scanning and the deviations from the metal master model were also evaluated. The results were as follows; 1. The distance between A-B, A-C, A-D, A-E, B-C, B-D of the abutments A, B, C, D, E of each cast material was calculated. And after comparing the deviations between the metal master model. $Fujirock^{(R)}$ showed the lowest value with $0.20{\pm}0.22mm$, and the deviation increased in the order of $Suprastone^{(R)}$, Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. 2. In each calculation area, the difference in measurements between cast material and metal master model showed singificant difference between A-B and Cross arch measure-ments of A-D, B-D, A-E(p<0.05). 3. The difference in measurements between cast material and metal master model in the A-B area showed $Fujirock^{(R)}$ to be the lowest with $0.05{\pm}0.04$mm and increased in the order of Die $Keen^{(R)}$, $Suprastone^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and $Suprastone^{(R)}$, Epoxy $Die^{(R)}$ (p<0.05). 4. The difference in measurements between cast material and metal master model in the B-C area showed $Fujirock^{(R)}$ to bo the lowest with $0.17{\pm}0.11$mm and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Die $Keen^{(R)}$, Epoxy $Die^{(R)}$(p<0.05). 5. The difference in measurements between cast material and metal master model in the B-D area showed $Fujirock^{(R)}$ to bo the lowest with $0.13{\pm}0.07$mm, Epoxy $Dies^{(R)}$and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fuji-rock^{(R)}$ and Die Keen(p<0.05). 6. In this experiment, Epoxy $Dies^{(R)}$ showed mean contraction in every calculation area. And when reconstruction cross arch restorations it is thought that distortion should be considered in every cast material.

  • PDF

Production planning in fish farm (어류양식장 생산계획에 관한 연구)

  • EH, Youn-Yang
    • The Journal of Fisheries Business Administration
    • /
    • v.46 no.3
    • /
    • pp.129-141
    • /
    • 2015
  • Because land based aquaculture is restricted by high investment per rearing volume and control cost, good management planning is important in Land-based aquaculture system case. In this paper master production planning was made to decide the number of rearing, production schedule and efficient allocation of water resources considering biological and economic condition. The purpose of this article is to build the mathematical decision making model that finds the value of decision variable to maximize profit under the constraints. Stocking and harvesting decisions that are made by master production planning are affected by the price system, feed cost, labour cost, power cost and investment cost. To solve the proposed mathematical model, heuristic search algorithm is proposed. The model Input variables are (1) the fish price (2) the fish growth rate (3) critical standing corp (4) labour cost (5) power cost (6) feed coefficient (7) fixed cost. The model outputs are (1) number of rearing fish (2) sales price (3) efficient allocation of water pool.

Force Feedback Control of 3 DOF Haptic Device Utilizing Electrorheological Fluid (ER 유체를 이용한 3 자유도 햅틱 장치의 힘 반향 제어)

  • Han, Y.M.;Kang, P.S.;Choi, S.B.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.11a
    • /
    • pp.213-216
    • /
    • 2005
  • This paper presents force feedback control performance of a 3DOF haptic device that can be used for minimally invasive surgery (MIS). As a first step, a 3DOF electrorheological (ER) joint is designed using a spherical mechanism. And it is optimized based on the mathematical torque modeling. Subsequently, the master haptic device is manufactured by the spherical joint. In order to achieve desired force trajectories, model based compensation strategy is adopted for the ER master. Therefore, Preisach model fur the PMA-based ER fluid is identified using experimental first order descending (FOD) curves. A compensation strategy is then formulated through the model inversion to achieve desired force at the ER master. Tracking control performances for sinusoidal force trajectory are presented, and their tracking errors are evaluated.

  • PDF

A Simulation Model for Master Production Schedule (MPS) Evaluation System (기준생산계획 평가 시스템을 위한 시뮬레이션 모델)

  • 최성훈
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 1998.03a
    • /
    • pp.106-110
    • /
    • 1998
  • Some successful scheduling systems are based on simulation technique. However, they are relatively expensive. A cost-effective solution is to apply general-purpose simulation software to the scheduling system. This paper is concerned with developing a simulation model for MPS(Master Production Schedule) evaluation system. The target system of the model is PC production system. AIM (Analyzer for Improving Manufacturing system), a well-known manufacturing oriented simulation software, is used for modeling tool. Eventually, the model can be included into an MPS evaluation system as simulation module and a scheduler can use the system to verify the MPS in advance.

  • PDF

The effects of scaling factors and quantization in sensors on free motion of teleoperation system

  • Hwang, Dal-Yeon;Cho, SangKyu;Park, Sanguk
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1997.10a
    • /
    • pp.1512-1515
    • /
    • 1997
  • One of the advantages of master-slave teleoperation is scaling concept such as position scaling, force scaling Meanuhile, lots of quantization effects are generated from position and force sensors in the master and slave manipulator. In this paper, to show the output error caused by the quantizaion effects from the position sensor and position scaling factor, simulation is done for free motion without contact in slave side. Transfer functiion model in which the quantization effect is assumed to be a disturbance input to the system is derived. Model shows that Jacobian, scaling factors, and controller affect the output by quantization effects form esnsors. One dof master and slave are used for simulation. In our study, the higher sensor resolution decreases the output error form quantization. Scaling factors can amplify the quantizatiion effects form the sensors in master and slave manipulators.

  • PDF

A Master Data Management Framework for Medium-Sized Companies (중견기업을 위한 마스터 데이터 관리 프레임웍)

  • Park, Kwang-Ho
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.31 no.4
    • /
    • pp.66-76
    • /
    • 2008
  • In medium-sized enterprises that comprise of multiple business branches and companies, various types of information systems are constructed and operated. One of the difficult problems these enterprises face is that integrated information cannot be delivered due to loosely managed mater data. This paper proposes an effective master data management framework for these enterprises. The framework is designed after comparing a tightly controlled centralization model with a coordinated centralization model. Through a case study on a customer master data integration project, the practicality of the framework is explored.

A Study on Tool Offset for Cutting of the Polyurethane Foam (폴리우레탄폼 절삭가공시 공구보정에 관한 연구)

  • Min, Se-Hong;Kim, Hei-Song
    • Journal of the Korean Society of Safety
    • /
    • v.15 no.2
    • /
    • pp.31-35
    • /
    • 2000
  • After constructing master model utilizing CAD data originated by sketch, product NC data for polyurethane foam using digitized master model data. And model cutting is performed utilizing specially developed polyurethane foam cutting tool in machining center. In this study, it is discussed to construct concept of tool offset, method of tool offset and feature tolerance, etc., that is impossible for cutting of the polyurethane foam by CNC machine.

  • PDF

Development of Rapid Tooling using Investment Casting & R/P Master Model (R/P 마스터 모델을 활용한 정밀주조 부품 및 쾌속금형 제작 공정기술의 개발)

  • Jeong, Hae-Do;Kim, Hwa-Young
    • Journal of Korea Foundry Society
    • /
    • v.20 no.5
    • /
    • pp.330-335
    • /
    • 2000
  • Functional metal prototypes are often required in numerous industrial applications. These components are typically needed in the early stage of a project to determine form, fit and function. Recent R/P(Rapid Prototyping) part are made of soft materials such as plastics, wax, paper, these master models cannot be employed durable test in real harsh working environment. Parts by direct metal rapid tooling method, such as laser sintering, by now are hard to get net shape, pores of the green parts of powder casting method must be infiltrated to get proper strength as tool, and new type of 3D direct tooling system combining fabrication welding arc and cutting process is reported. But a system which can build directly 3D parts of high performance functional material as metal park would get long period of system development, massive investment and other serious obstacles, such as patent. In this paper, through the rapid tooling process as silicon rubber molding using R/P master model, and fabricate wax pattern in that silicon rubber mold using vacuum casting method, then we translated the wax patterns to numerous metal tool prototypes by new investment casting process combined conventional investment casting with rapid prototyping & rapid tooling process. With this wax-injection-mold-free investment casting, we developed new investment casting process of fabricating numerous functional metal prototypes from one master model, combined 3-D CAD, R/P and conventional investment casting and tried to expect net shape measuring total dimension shrinkage from R/P pare to metal part.

  • PDF

Rasch Analysis of the Korean Western Ontario McMaster (KWOMAC): In the Out-Patients Over 65 Years With Osteoarthritis of the Knee (한국판 Western Ontario MacMaster(WOMAC)의 Rasch분석)

  • Koh, Eun-Kyung;Yi, Chung-Hwi
    • Physical Therapy Korea
    • /
    • v.14 no.1
    • /
    • pp.82-89
    • /
    • 2007
  • The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is a valid and widely used instrument for the assessment of osteoarthritis patients. In this study, data was obtained from the out-patients with painful osteoarthritis of the knee. One hundred-three out-patients were interviewed by physical therapists. In an exploratory way, a Korean version of the KWOMAC was analyzed for unidimensionality, item separation, and item difficulty using the Winsteps programs. Ninety-five patients with osteoarthritis of the knee over 65 years were analyzed for Rash analysis. In the analysis several functional items poorly fit to the model. These items included "heavy domestic duties" and "standing". In the pain domain, one item ("at night while in bed") did not fit the model. In the stiffness domain one item ("after sitting, lying, or resting later in the day") did not fit the model. Although 4 items from the 3 domains (pain, stiffness, function domain) do not fit well, the KWOMAC domains were confirmed by Rasch analysis. Thus the KWOMAC needs to be further examined before it can be used to properly determine the health status of the elderly with OA.

  • PDF

Structural Variation of Alu Element and Human Disease

  • Kim, Songmi;Cho, Chun-Sung;Han, Kyudong;Lee, Jungnam
    • Genomics & Informatics
    • /
    • v.14 no.3
    • /
    • pp.70-77
    • /
    • 2016
  • Transposable elements are one of major sources to cause genomic instability through various mechanisms including de novo insertion, insertion-mediated genomic deletion, and recombination-associated genomic deletion. Among them is Alu element which is the most abundant element, composing ~10% of the human genome. The element emerged in the primate genome 65 million years ago and has since propagated successfully in the human and non-human primate genomes. Alu element is a non-autonomous retrotransposon and therefore retrotransposed using L1-enzyme machinery. The 'master gene' model has been generally accepted to explain Alu element amplification in primate genomes. According to the model, different subfamilies of Alu elements are created by mutations on the master gene and most Alu elements are amplified from the hyperactive master genes. Alu element is frequently involved in genomic rearrangements in the human genome due to its abundance and sequence identity between them. The genomic rearrangements caused by Alu elements could lead to genetic disorders such as hereditary disease, blood disorder, and neurological disorder. In fact, Alu elements are associated with approximately 0.1% of human genetic disorders. The first part of this review discusses mechanisms of Alu amplification and diversity among different Alu subfamilies. The second part discusses the particular role of Alu elements in generating genomic rearrangements as well as human genetic disorders.