• Title/Summary/Keyword: New formulation

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Mathematical Programming Approaches to GT Cell Formation: A Comparative Study

  • 원유경
    • Journal of the Korean Operations Research and Management Science Society
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    • v.16 no.2
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    • pp.137-137
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    • 1991
  • This paper compares and evaluates the performances of the two types of mathematical programming models for solving the machine-part cell formation problem in group technology manufacturing : indirect formulation relying on surrogate measure such as similarity coefficient and direct formulation seeking to minimize the number of exceptional elements. New indirect formulation, called the generalized p-median model. is proposed. Unlike existing p-median formulations, proposed formulation includes the classical cell formation problem in which only one process plan exsits for each part as a special case. The proposed new formulation can also deal with the cell formation problem in which alternative process plans exist for a part. The indirect formulation is compared with a new direct formulation which needs much fewer extra variables and constraints than existing direct formulations. Some significant findings from comparative experiment are discussed.

Mathematical Programming Approaches to GT Cell Formation: A Comparative Study

  • 원유경
    • Korean Management Science Review
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    • v.16 no.2
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    • pp.137-147
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    • 1999
  • This paper compares and evaluates the performances of the two types of mathematical programming models for solving the machine-part cell formation problem in group technology manufacturing : indirect formulation relying on surrogate measure such as similarity coefficient and direct formulation seeking to minimize the number of exceptional elements. New indirect formulation, called the generalized {{{{ { p}_{ } }}-median model. is proposed. Unlike existing {{{{ { p}_{ } }}-median formulations, proposed formulation includes the classical cell formation problem in which only one process plan exsits for each part as a special case. The proposed new formulation can also deal with the cell formation problem in which alternative process plans exist for a part. The indirect formulation is compared with a new direct formulation which needs much fewer extra variables and constraints than existing direct formulations. Some significant findings from comparative experiment are discussed.

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A simple method of stiffness matrix formulation based on single element test

  • Mau, S.T.
    • Structural Engineering and Mechanics
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    • v.7 no.2
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    • pp.203-216
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    • 1999
  • A previously proposed finite element formulation method is refined and modified to generate a new type of elements. The method is based on selecting a set of general solution modes for element formulation. The constant strain modes and higher order modes are selected and the formulation method is designed to ensure that the element will pass the basic single element test, which in turn ensures the passage of the basic patch test. If the element is to pass the higher order patch test also, the element stiffness matrix is in general asymmetric. The element stiffness matrix depends only on a nodal displacement matrix and a nodal force matrix. A symmetric stiffness matrix can be obtained by either modifying the nodal displacement matrix or the nodal force matrix. It is shown that both modifications lead to the same new element, which is demonstrated through numerical examples to be more robust than an assumed stress hybrid element in plane stress application. The method of formulation can also be used to arrive at the conforming displacement and hybrid stress formulations. The convergence of the latter two is explained from the point of view of the proposed method.

A New Formulation of System Reliability for Consecutive k out of n Structure with Sink-Source Pole

  • Oh, Chung-Hwan
    • Journal of Korean Society for Quality Management
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    • v.21 no.1
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    • pp.121-135
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    • 1993
  • The derived expressions and computations of the system reliability in the consecutive k out of n failure structure with sink-source pole are discussed and a new simplified formulation to compute the reliability of consecutive k out of $n^*$ failure system is presented, and the relations with system reliability when the number of first consecutive falied components from source is greater than k are presented in this paper. The new simplified formulation is illustrated in the numerical experiments.

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Development of the stable liquid formulation of Burkholderia cepacia YC5025, a biocontrol agent for cucumber anthracnose

  • Chung, Eu-Jeen;Chung, Young-Ryun
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.97.2-98
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    • 2003
  • A new and effective formulation using antagonistic bacteria, Burkholderia cepacia YC5025 in vegetable oil was developed for the biocontrol of anthracnose. The bacterial population in the formulation was maintained to 5x10/sup7/ cfu/ml upto 60 days at room temperature. Control efficacy of the formulation for anthracnose was over 80% by spraying of diluted suspension(x1,000) in growth chamber tests. On the contrary, the bacterial suspension in distilled water or bacterial culture broth containing same number of spores as the formulation had low control efficacy around 40% even 2-weeks storage after preparation. The shelf-life of the formulation was longer than that of bacterial preparation using clay minerals such as talc or bentonite. The mechanisms of newly developed bacterial formulation are possibly the formation of water film on the surface of cucumber leaves and inactivation of the bacteria in the vegetable oils during storage. Further field tests and improvements with new liquid bacteiral formulation need to be done for practical application.

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Stability Improvement of Amlodipine Maleate Tablets using Aqueous Polymer Coating Technique (친수성 폴리머 제피를 이용한 말레인산암로디핀 정제의 안정성 개선)

  • Choi, In-Sik;Shin, Taek-Hwan;Choi, Sung-Up;Lee, Jae-Hwi;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.34 no.5
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    • pp.407-411
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    • 2004
  • New formulations of amlodipine maleate tablet have been investigated to enhance the stability of the drug against light and humidity. Three kinds of amlodipine maleate tablets were prepared. One is prepared by previously known formulation (formulation C), the others were by new formulations using hydrophilic polymer $(Opadry^{\circledR})$ coated granules (formulations A and B). Amlodipine maleate powder was coated with $Opadry^{\circledR}$ to produce the coated granules and it was mixed with other excipients to produce the tabletting mass of new formulations A and B. Dissolution rate of newly formulated tablets was over 80% within 10 minutes in 0.01 M HCl medium, and its dissolution pattern was similar to that of $Norvasc^{\circledR}$ tablet. After 6 months storage under accelerated conditions, residual drug contents of tested formulations (A and B) were not significantly different from formulation C, ranging from 96.2 to 100.4%. Meanwhile, dissolution amount of formulation C was significantly reduced compared to that of formulation A (p<0.05), showing formulation A was more stable than unprotected formulation C at the accelerated conditions. Results of appearance, hardness and disintegration remained unchanged during stability study. In conclusion, it showed that the new formulations had enhanced the stability characteristics and hydrophilic coating technique was an alternative and promising method to improve the stability of amlodipine maleate tablet.

Exploratory Structural Analysis on Eight Positions for New Formulations in Jingyuequanshu by Network Analysis (네트워크 분석을 이용한 『영악전서(景岳全書)』 신방팔진(新方八陣)의 탐색적 구조 분석)

  • Jeong, Yunkyeong;Kim, Hyungsuk;Kim, Hyunho;Park, Young-Jae;Park, Young-Bae
    • The Journal of Korean Medicine
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    • v.35 no.3
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    • pp.49-59
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    • 2014
  • Background: Eight positions for new formulations in Jingyuequanshu is a unique classifying system and each position can be presented as a network. Network analysis is an effective method of visualizing the relationship of textual information. Purpose: This study aimed to analyze the structure of the eight positions for new formulations in Jingyuequanshu, and to acquire information about composing materia medica. Methods: We constructed an initial database and binary matrix of eight positions for new formulation in Jingyuequanshu, including its herbs and formulations. With this data, we carried out frequency and network analysis. Results: We analyzed each of the eight positions for new formulation, entire positions, and five positions after removing 'causal/cold/hot' positions. We found that the formulas of the causal position are distributed throughout the new formulation, and those of the cold and hot positions are also distributed similarly but the two groups are exclusive to each other. The other 5 positions are distributed exclusively to one another. Conclusions: Eight positions for new formulation of Jingyuequanshu were classified into three axes by exploratory network analysis. One is an axis of causal position, another is an axis of cold/hot positions, and the last is an axis of the other five positions.

On the Extension of Insecticidal Activity and the Preparation of New Mixture with Diazinon (농약의 약효증진을 위한 첨가제 효과에 관하여;Diazinon제를 중심으로)

  • Cho, Jeong-Rye;Lee, Kyu-Seung
    • Korean Journal of Environmental Agriculture
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    • v.15 no.1
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    • pp.105-115
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    • 1996
  • In this paper, we reviewed the degradation factors of diazinon which was known to be easily degraded by soil microorganisms and lost of its activity. Under submerged soil condition, the contribution of microorganisms to diazinon degradation was about 40% and these microorganisms preferred soil humus as substrates to diazinon itself. The effect of monooxygenase activity in submerged soil was more important than esterase activity on diazinon degradation and these enzymes were inhibited by several chemicals such as piperonyl butoxide(PBO), EPN and tricyclazole. From these results, new formulation type of diazinon (PBO and triphenyl phosphate were added to commercial diazinon formulation by 0.1% respectively.) and diazinon mixture formulation (diazinon was mixed with EPN, tricyclazole and carbofuran in equal amount) were prepared. The new formulation type of diazinon showed better insecticidal activity by 12% and more delayed diazinon degradation in ten days than commercial diazinon.

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A New Mathematical Formulation for the Classical Assembly Line Balancing Problem

  • Shin, Doo-Young;Lee, Daeyong
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.2
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    • pp.217-228
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    • 1994
  • This paper presents a new integer formulation (Type III ALB) for a single model assembly line balancing problem. The objective of the formulation is to minimize the total idle time, which is defined as the product of the number of work stations and the cycle times minus the total work content. This formulation considers currently existing Type I (minimizing the number of work stations for a given cycle time) and type II (minimizing the cycle time for a given number of work stations) formulations as its special cases and provides the global minimum solutions of the cycle time and the number of work stations. This information would be of great value to line designers involved in designing new assembly lines and rebalancing old lines under flexible conditions. Solution methods based on combination of Type I and Type II approaches are also suggested and compared.

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Analysis of RC beams subjected to shock loading using a modified fibre element formulation

  • Valipour, Hamid R.;Huynh, Luan;Foster, Stephen J.
    • Computers and Concrete
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    • v.6 no.5
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    • pp.377-390
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    • 2009
  • In this paper an improved one-dimensional frame element for modelling of reinforced concrete beams and columns subjected to impact is presented. The model is developed in the framework of a flexibility fibre element formulation that ignores the shear effect at material level. However, a simple shear cap is introduced at section level to take account of possible shear failure. The effect of strain rate at the fibre level is taken into account by using the dynamic increase factor (DIF) concept for steel and concrete. The capability of the formulation for estimating the element response history is demonstrated by some numerical examples and it is shown that the developed 1D element has the potential to be used for dynamic analysis of large framed structures subjected to impact of air blast and rigid objects.