A Model for Shortening the Length of Activities in Construction and Overhaul Planning: UPROB

2002 ◽  
Author(s):  
Niko Majdandzˇic´ ◽  
Slavko Sebastijanovic´ ◽  
Gordana Maticˇevic´ ◽  
Nebojsˇa Sebastijanovic´
Keyword(s):  
Mathematical Model ◽  
Thermal Energy ◽  
Input Data ◽  
Critical Path ◽  
Planning System ◽  
Task Completion ◽  
Assembly Lines ◽  
Total Cost ◽  
Activity Cost ◽  
Optimal Variation

This paper presents a mathematical model of the UPROB (planning system for construction and overhaul) system that was developed for tank assembly lines, construction of thermal energy structures, and for performing an overhaul in complex plants. Planning technology includes utilizing linear diagrams with a direct usage of input data from a plant’s database. A model has been developed to determine the critical path and also, to define steps for the most economical shortening of the entire plan. Several plan variations are developed (according to specified goals) and the management determines the optimal variation. After selecting a plan, it is possible to control and create work orders for individual tasks in certain activities. Task completion percentage, activity cost, and the total cost of the plan are also provided.

The Automatic Generation of a Mathematical Model for Machinery Systems

1973 ◽  
Vol 95 (2) ◽  
pp. 629-635 ◽  
Author(s):  
D. A. Smith ◽  
M. A. Chace ◽  
A. C. Rubens
Keyword(s):  
Mathematical Model ◽  
Graph Theory ◽  
Computer Program ◽  
Mechanical System ◽  
Input Data ◽  
Automatic Generation ◽  
Electrical Networks ◽  
Lagrange’S Equation ◽  
Detailed Explanation ◽  
Independent Loops

This paper presents a detailed explanation of a technique for automatically generating a mathematical model for machinery systems. The process starts from a relatively small amount of input data and develops the information required to model a mechanical system with Lagrange’s equation. The technique uses elements of graph theory which were developed for electrical networks. The basic identifications required for mechanical systems are: paths from ground to mass centers, the independent loops of parts, if any, and paths associated with applied force effects. The techniques described in this paper have been used successfully in a generalized computer program, DAMN.

scholarly journals AGV Brake System Simulation

2019 ◽  
Vol 10 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Daniel Varecha ◽  
Robert Kohar ◽  
Frantisek Brumercik
Keyword(s):  
Mathematical Model ◽  
Input Data ◽  
Initial Conditions ◽  
Brake System ◽  
Disc Brake ◽  
Hydraulic Control ◽  
Stopping Distance ◽  
Braking Force ◽  
Braking Process ◽  
The Mathematical Model

Abstract The article is focused on braking simulation of automated guided vehicle (AGV). The brake system is used with a disc brake and with hydraulic control. In the first step, the formula necessary for braking force at the start of braking is derived. The stopping distance is 1.5 meters. Subsequently, a mathematical model of braking is created into which the formula of the necessary braking force is applied. The mathematical model represents a motion equation that is solved in the software Matlab by an approximation method. Next a simulation is created using Matlab software and the data of simulation are displayed in the graph. The transport speed of the vehicle is 1 〖m.s〗^(-1) and the weight of the vehicle is 6000 kg including load. The aim of this article is to determine the braking time of the device depending from the input data entered, which represent the initial conditions of the braking process.

scholarly journals Predicting Temporal Exceptions in Concurrent Workflows

2012 ◽  
pp. 196-218 ◽  
Author(s):  
Iok-Fai Leong ◽  
Yain-Whar Si ◽  
Robert P. Biuk-Aghai
Keyword(s):  
Business Processes ◽  
Critical Path ◽  
Workflow Management ◽  
Business Environment ◽  
Complex Problem ◽  
Control Flow ◽  
Prediction Algorithm ◽  
Task Completion ◽  
Ripple Effect ◽  
Long Duration

Current Workflow Management Systems (WfMS) are capable of managing simultaneous workflows designed to support different business processes of an organization. These departmental workflows are considered to be interrelated since they are often executed concurrently and are required to share a limited number of resources. However, unexpected events from the business environment and lack of proper resources can cause delays in activities. Deadline violations caused by such delays are called temporal exceptions. Predicting temporal exceptions in concurrent workflows is a complex problem since any delay in a task can cause a ripple effect on the remaining tasks from the parent workflow as well as from the other interrelated workflows. In addition, different types of loops are often embedded in the workflows for representing iterative activities, and presence of such control flow patterns in workflows can further increase the difficulty in estimation of task completion time. In this chapter, the authors describe a critical path based approach for predicting temporal exceptions in concurrent workflows that are required to share limited resources. This approach allows predicting temporal exceptions in multiple attempts while workflows are being executed. The accuracy of the proposed prediction algorithm is analyzed based on a number of simulation scenarios. The result shows that the proposed algorithm is effective in predicting exceptions for instances where long duration tasks are scheduled (or executed) at the early phase of the workflow.

Simulation of fuel bed ignition by wildland firebrands

2018 ◽  
Vol 27 (8) ◽  
pp. 550 ◽  
Author(s):  
O. V. Matvienko ◽  
D. P. Kasymov ◽  
A. I. Filkov ◽  
O. I. Daneyko ◽  
D. A. Gorbatov
Keyword(s):  
Mathematical Model ◽  
Pinus Sylvestris ◽  
Mathematical Modelling ◽  
Thermal Energy ◽  
Ignition Time ◽  
Pine Bark ◽  
Bark Sample ◽  
Airflow Velocity ◽  
Experimental Conditions ◽  
Series Of Experiments

A 3-D mathematical model of fuel bed (FB) ignition initiated by glowing firebrands originating during wildland fires is proposed. In order to test and verify the model, a series of experiments was conducted to determine the FB ignition time by a single pine bark and twig firebrand (Pinus sylvestris). Irrespective of the pine bark sample sizes and experimental conditions, the ignition of the FB was not observed. Conversely, pine twigs, under certain parameters, ignited the FB in the range of densities (60–105 kg m−3) and with the airflow velocity of ≥2 m s−1. The results of the mathematical modelling have shown that a single pine bark firebrand ≤5 cm long with a temperature of T ≤ 1073 K does not ignite in the flaming mode the FB, and only the thermal energy of larger particles is sufficient for flaming ignition of the adjacent layers of the FB. The analysis of the results has shown that the firebrand length is a major factor in the initiation of ignition. Comparison of the calculated and observed FB ignition times by a single firebrand have shown that our modelling accords well with the experimental results.

Cost Analysis and Fuzzy Control for Collapsible Container Usage Based on Closed-Loop Supply Chain Model

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
Xinyan Ou ◽  
Jorge Arinez ◽  
Qing Chang ◽  
Guoxian Xiao
Keyword(s):  
Mathematical Model ◽  
Fuzzy Control ◽  
Closed Loop ◽  
Control Method ◽  
Fuzzy Controller ◽  
Accurate Estimation ◽  
Chain Model ◽  
Market Demand ◽  
Total Cost ◽  
Logistic Cost

In the last decade, global competition has forced manufacturers to optimize logistics. The implementation of collapsible containers provides a new perspective for logistics cost savings, since using collapsible containers reduces the frequency of shipping freight. However, optimization of logistic cost is complicated due to the interactions in a system, such as market demand, inventory, production throughput, and uncertainty. Therefore, a systematic model and accurate estimation of the total cost and system performance are of great importance for decision making. In this paper, a mathematical model is developed to describe deterministic and stochastic scenarios for a closed-loop container dynamic flow system. The uncertainties in a factory and a supplier are considered in the model. The performance evaluation of the collapsible container system and total cost estimation are provided through model analysis. Furthermore, fuzzy control method is proposed to monitor the processing rate of the supplier and the factory and to adjust the rate of the supplier operation then further reduce the logistic cost. A case study with a matlab simulation is presented to illustrate the accuracy of the mathematical model and the effectiveness of the fuzzy controller.

scholarly journals Mathematical Model for Proactive Resequencing of Mixed Model Assembly Lines

2019 ◽  
Vol 33 ◽  
pp. 438-445
Author(s):  
Achim Kampker ◽  
Kai Kreisköther ◽  
Marius Schumacher
Keyword(s):  
Mathematical Model ◽  
Mixed Model ◽  
Assembly Lines ◽  
Mixed Model Assembly Lines ◽  
Mixed Model Assembly

A Simple Mathematical Model of Metal Hydride Elements for Thermal Powered Plants

1993 ◽  
Vol 207 (2) ◽  
pp. 89-94 ◽  
Author(s):  
V M Liventsov ◽  
A V Kuznetsov
Keyword(s):  
Mathematical Model ◽  
Dynamic Response ◽  
Thermal Energy ◽  
Metal Hydride ◽  
Simple Mathematical Model ◽  
Model Calculations ◽  
Stationary Method ◽  
Different Types ◽  
Simplified Mathematical Model

This paper proposes a model for metal hydride elements which are used as hydrogen accumulators for different types of thermal powered systems. The quasi-stationary method has been used to obtain a simplified mathematical model. Calculations to predict the dynamic response of a thermal energy engine have been made.

Multi-period reverse logistics network design with emission cost

2017 ◽  
Vol 28 (1) ◽  
pp. 127-149 ◽  
Author(s):  
Sajan T. John ◽  
Rajagopalan Sridharan ◽  
P.N. Ram Kumar
Keyword(s):  
Mathematical Model ◽  
Network Design ◽  
Reverse Logistics ◽  
Planning Horizon ◽  
Mixed Integer ◽  
Single Type ◽  
Reverse Supply Chain ◽  
Design Decisions ◽  
Content Type ◽  
Total Cost

Purpose The purpose of this paper is to develop a mathematical model for the network design of a reverse supply chain in a multi-product, multi-period environment. The emission cost due to transportation activities is incorporated into the model to reduce the total cost of emission and study the significance of inclusion of emission cost on the network design decisions. Design/methodology/approach Mixed integer linear programming formulation is used to model the network. The developed model is solved and analysed using the commercial solver LINGO. Findings The mathematical model provides a unified design of the network for the entire planning horizon comprising of different periods. A reduction in the total cost of emission is achieved. The analysis of the problem environment shows that the network design decisions significantly vary with the consideration of emission cost. Research limitations/implications A single mode of transportation is considered in this study. Also, a single type of vehicle is considered for the transportation purpose. Practical implications The developed model can aid the decision makers in making better decisions while reducing the total emission cost. The quantification of the emission cost due to transportation activities is presented in an Indian context and can be used for future studies. Originality/value An all-encompassing approach for the design of reverse logistics networks with explicit consideration of product structure and emission cost.

Image Mosaic Technology Based on Matlab Simulation

2014 ◽  
Vol 556-562 ◽  
pp. 4990-4993
Author(s):  
Chang Kun Shao
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Matrix Theory ◽  
Planning System ◽  
Rate Of Return ◽  
Image Mosaic ◽  
Matlab Simulation ◽  
Tourism Planning ◽  
Sports Tourism ◽  
Characteristic Values

This paper uses multivariate planning mathematical model to establish sports tourism planning system, and introduces multiple matrix theory, extracts four characteristic values of the tourist traffic, service, security and environment, realizes the multivariate planning of tourism system. This paper uses the MATLAB software to do numerical simulation on proportion and the expected rate of return for the four characteristic values in planning, we get the multivariate distribution nephogram and rendering nephogram, finally use image mosaic technique of MATLAB to synthetize green planning blueprint of sports tourism. It provides the technical reference for the research on city sports tourism planning.

scholarly journals MODELS OF GENERATION OF INPUT DATA OF TRAINING OF NEURAL NETWORK MODULES FOR DIAGNOSTIC OF DISEASES IN UROLOGY

2019 ◽  
pp. 116-122
Author(s):  
Mykola Ivanovych Fedorenko
Keyword(s):  
Neural Network ◽  
Mathematical Model ◽  
Input Data ◽  
Probabilistic Approach ◽  
Training Data ◽  
Digital Data ◽  
Training Methods ◽  
Training Procedure ◽  
Network Modules ◽  
Parameter Values

The subject of the research presented in the article is neural network modules (NNMs), which are used to solve problems in the practice of diagnosing diseases in urology. This work aims to develop a mathematical model for generating a multitude of uroflowmetric parameters, in particular, graphs of uroflowrograms of the required volume, used as input data for NNM training. Objective: to develop a mathematical model for the formation of uroflowmetric parameters using a probabilistic approach based on a uniform "white noise". To develop an effective algorithm for the procedure for generating new parameter values and tools for its implementation. Methods used: NNM training methods, mathematical modeling methods, digital signal processing methods, tools for generating and processing random numerical sequences, digital data filtering methods. The following results were obtained: when creating and implementing a mathematical model for generating a large amount of training data, the requirements of randomness are taken into account when obtaining new values of uroflowmetric parameters. And at the same time, the obtained noise values are filtered to values of a given range, which are percentage-wise comparable to the amplitude value of the uroflowmetric parameter. Conclusions. The scientific novelty of the results is as follows: the NNM training method for recognizing diseases in urology has been improved by developing a mathematical model to generate uroflowmetric parameters for NNM training. The presented model allows you to create the necessary amount of data for training neural network modules in the course of experimental research on the recognition of diseases. The generation of uroflowmetric parameters is based on adding noise to the parameter values. This allows you to change the input data of the NNM training in a given range. This ensures the creation of the required input volume of the NNM training procedure. In the future, this contributes to the testing process of trained neural network modules with reliable information on the diagnosis of diseases in urology.

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