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Articles 421 - 450 of 692

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Precise Measuring Cells For Quantitative And Qualitative Measurement, A.A. Begunov, B.M. Akhmedov, R.A. Ibragimov Feb 2020

Precise Measuring Cells For Quantitative And Qualitative Measurement, A.A. Begunov, B.M. Akhmedov, R.A. Ibragimov

Chemical Technology, Control and Management

The main provisions considered in assessing the accuracy of methods and measurement results are considered. It is shown that in the experimental assessment of various accuracy indicators, and also when analyzing the content of components in various gaseous media, the sorption-gravimetric measurement method is widely used, methods for measuring the mass of the sorbent and possible sources of error of this technique. Methods of measuring the mass of gas using specific surface areas, including taking into account the contact of gas with a solid material, and also, the amount of adsorbed gas and its pressure, temperature, type and size of …


Controlling And Forecasting The Reliability Of Integrated Circuits Of Radio Systems Transmitting Information, Abdulaziz M. Nazarov Prof, Dilmurod A. Davronbekov Prof. Feb 2020

Controlling And Forecasting The Reliability Of Integrated Circuits Of Radio Systems Transmitting Information, Abdulaziz M. Nazarov Prof, Dilmurod A. Davronbekov Prof.

Chemical Technology, Control and Management

The issues of forecasting the reliability of integrated circuits, which are the main element base of modern radio engineering information transmission systems, are considered. Methods of parametric and functional control are described to determine the correspondence of the static and dynamic parameters of microcircuits to the required values. A combined method for determining the operating parameters of microcircuits is also described. The advantage of this method in addition to the two above methods is indicated that it combines the function of controlling the operation of the entire control system. Two approaches for predicting reliability are given, as well as mathematical …


Features Of Hydration Process, Structure Formation And Curing Processes Of Mono And Polymineral Cement In The Presence Of Additives Of Solid Waste Of Soda Production, Nargis Shamadinova, Gulnora Abdukadirovna Tokhtakhunova Phd, Temur Azimovich Atakuziev, Shakhnoza Saidanvarovna Rakhimjanova Feb 2020

Features Of Hydration Process, Structure Formation And Curing Processes Of Mono And Polymineral Cement In The Presence Of Additives Of Solid Waste Of Soda Production, Nargis Shamadinova, Gulnora Abdukadirovna Tokhtakhunova Phd, Temur Azimovich Atakuziev, Shakhnoza Saidanvarovna Rakhimjanova

Chemical Technology, Control and Management

The influence of the additive of solid waste of soda production (SWSP) on the content of -C2S and C3S in cement studied. It was found that SWSP affects the density of the aluminum-containing minerals C3A and C4AF, in addition, in the presence of gypsum, their plasticizing properties improved. The introduction of SWSP additives during grinding of clinker intensifies the grinding process and made it possible to obtain a more plastic cement. It was proved that SWSP with CaCl2 content can be used as an additive to concrete and cement mortars - …


Investigating The Solution Properties Of Population Model Of Cross-Diffusion Model With Double Nonlinearity And With Variable Density, Dildora Kabilovna Muhamediyeva Feb 2020

Investigating The Solution Properties Of Population Model Of Cross-Diffusion Model With Double Nonlinearity And With Variable Density, Dildora Kabilovna Muhamediyeva

Chemical Technology, Control and Management

The models of two competing populations with double nonlinear diffusion and three types of functional dependencies are considered. The first dependence corresponds to the Malthusian type, the second to the Verhühlst type (logistic population), and the third to Olli-type populations. A common element of this kind of description is the presence of a linear source. Nonlinear sinks are also present in descriptions of populations of the Verhulst and Ollie type. Suitable initial approximations for a rapidly converging iterative process are proposed. Based on a self-similar analysis and comparison of the solutions of the Cauchy problem in the domain for an …


Techniques To Solve Decision-Making Problems, Dilnoz Tulkunovna Muhamediyeva, Bekmuratov Fayzievich Tulkun Feb 2020

Techniques To Solve Decision-Making Problems, Dilnoz Tulkunovna Muhamediyeva, Bekmuratov Fayzievich Tulkun

Chemical Technology, Control and Management

Solving decision-making problems in poorly formalized systems only with the help of deterministic and probabilistic methods is insufficient. To do this, it is necessary to widely apply the methods of hybrid intelligent systems and, especially, the methods of “soft” calculations (SoftCalculation, SoftComputing) and the directions of ComputationalIntelligence — intelligent computing technologies that are emerging on this theoretical and methodological base. An immune - fuzzy algorithm for the synthesis of fuzzy inference systems (FIS) is proposed. A two-stage adaptive FIS synthesis algorithm is described. At the first stage, the initial fuzzy parameters are clustered in order to reduce the number of …


Neuro-Fuzzy Modeling For Predictive Control Systems With Complex Technological Processes And Production, Yusupbekov Nodirbek, Shukhrat Gulyamov, Malika Doshchanova Feb 2020

Neuro-Fuzzy Modeling For Predictive Control Systems With Complex Technological Processes And Production, Yusupbekov Nodirbek, Shukhrat Gulyamov, Malika Doshchanova

Chemical Technology, Control and Management

The paper implements a modification of a fuzzy neural network, which is suitable for predictive control purposes. Adaptation of a multidimensional programmable controller based on a neural algorithm for the back propagation of forecasting errors is proposed, as well as neural parametric identification of a fuzzy mathematical model of complex technological processes and production based on experimental data and expert estimates.


Steady Algorithms For Synthesis Of Multidimensional Controlling Systems With Incomplete Information About The Object State, Uktam Farkhodovich Mamirov Feb 2020

Steady Algorithms For Synthesis Of Multidimensional Controlling Systems With Incomplete Information About The Object State, Uktam Farkhodovich Mamirov

Chemical Technology, Control and Management

In this paper, questions of forming and creation of steady synthesis algorithms of multidimensional controlling systems at incomplete information on object status are considered. It is shown that the matrix of feedback coupling on a status at the complete information is not determined. The different algorithms of steady calculation of a matrix pseudo-inverse to the matrix of outputs using these or those decomposition of matrixes are analyzed. Algorithms of iterative specification of a required solution of "skeletal" decomposition are given. The given expressions allow synthesizing the simplified computing procedures of synthesis of multidimensional controlling systems at incomplete information on object …


Importance Of Morphological Features In Orthoptera Identification, Kamilov Mirzoyan, Alisher Khamroev, Hudayberdiev Mirzaakbar Feb 2020

Importance Of Morphological Features In Orthoptera Identification, Kamilov Mirzoyan, Alisher Khamroev, Hudayberdiev Mirzaakbar

Chemical Technology, Control and Management

This article analyzes the problems of implementing image recognition methods and algorithms for identifying biological objects. The Orthoptera group was chosen as a biological object. Orthoptera is a taxonomic order of insects that includes grasshoppers, crickets, locusts, and others. Approaches to the formation and identification of features of Orthoptera species and the formation of training and control samples of their samples are proposed. Estimation algorithms (ACE) were chosen as algorithmic support for identifying Orthoptera collections. ACE is based on the principle of partial priority. Approaches to the formation of a training and testing complex based on the data from the …


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


Short-Term Truckload Spot Rates' Prediction In Consideration Of Temporal And Between-Route Correlations, Wei Xiao, Chuan Xu, Hongling Liu, Hong Yang, Xiaobo Liu Jan 2020

Short-Term Truckload Spot Rates' Prediction In Consideration Of Temporal And Between-Route Correlations, Wei Xiao, Chuan Xu, Hongling Liu, Hong Yang, Xiaobo Liu

Computational Modeling & Simulation Engineering Faculty Publications

Truckload spot rate (TSR), defined as a price offered on the spot to transport a certain cargo by using an entire truck on a target transportation line, usually price per kilometer-ton, is a key factor in shaping the freight market. In particular, the prediction of short-term TSR is of great importance to the daily operations of the trucking industry. However, existing predictive practices have been limited largely by the availability of multilateral information, such as detailed intraday TSR information. Fortunately, the emerging online freight exchange (OFEX) platforms provide unique opportunities to access and fuse more data for probing the trucking …


Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat Jan 2020

Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat

Electronic Theses and Dissertations, 2020-2023

One of the most important factors in a nation's development is energy availability. All the aspects of its economy are directly proportional to the energy resources. Oil is one of the most sought energy resources currently. Solar energy is one of the most important renewable sources of energy available to us. With oil deposits depleting and current global warming, there is an emphasis on using more and more renewable sources or clean energy. This has led to immense research on solar cells and how it could better be used to get maximum output. Storage of energy is another aspect that …


Investigating The Feasibility, Procedures, Benefits, And Challenges Of Using Mixed Reality In Construction Projects: An Electrical Layout Case Study, Samjhana Shakya Jan 2020

Investigating The Feasibility, Procedures, Benefits, And Challenges Of Using Mixed Reality In Construction Projects: An Electrical Layout Case Study, Samjhana Shakya

Electronic Theses and Dissertations

Innovation and development of technology in the field of visualization have affected the way of designing, presenting, and interacting of the design in the architecture and construction industry. With the invention of the Mixed Reality (MR) device, HoloLens, 2016, many researchers and construction practitioners have marched their research of implementing the MR application in the construction industry. However, there is scarce research on the MR application review, the workflow of using BIM models with the HoloLens, its implementation in the site, and the benefits and challenges of the MR application in the construction site. The gap in the research needs …


Mathematical Modeling, Optimal Control And Stability Analysis For Dynamic Supply Chains, Yasser Alberto Davizon Jan 2020

Mathematical Modeling, Optimal Control And Stability Analysis For Dynamic Supply Chains, Yasser Alberto Davizon

Open Access Theses & Dissertations

Dynamic supply chains (SC) are important to reduce inventory, to enable the flow of materials, and maximize profits. By this, dynamic SC require proper decision-making with effective performance and synchronization. In operations and production planning processes, decision-makers develop convenient and suitable decisions, to validate their hypoThesis about which decisions incorporate more profit while reducing costs on enterprise operations. Based on this, inventory management plays a crucial point in the supply chain analysis. In general, SC processes raw material, cash, and information flows, taking into account the demand profile of the system. This research work presents the mathematical modeling, optimal control, …


Internet Of Things For Sustainable Mining, Abdul Salam Jan 2020

Internet Of Things For Sustainable Mining, Abdul Salam

Faculty Publications

The sustainable mining Internet of Things deals with the applications of IoT technology to the coupled needs of sustainable recovery of metals and a healthy environment for a thriving planet. In this chapter, the IoT architecture and technology is presented to support development of a digital mining platform emphasizing the exploration of rock–fluid–environment interactions to develop extraction methods with maximum economic benefit, while maintaining and preserving both water quantity and quality, soil, and, ultimately, human health. New perspectives are provided for IoT applications in developing new mineral resources, improved management of tailings, monitoring and mitigating contamination from mining. Moreover, tools …


Internet Of Things In Sustainable Energy Systems, Abdul Salam Jan 2020

Internet Of Things In Sustainable Energy Systems, Abdul Salam

Faculty Publications

Our planet has abundant renewable and conventional energy resources but technological capability and capacity gaps coupled with water-energy needs limit the benefits of these resources to citizens. Through IoT technology solutions and state-of-the-art IoT sensing and communications approaches, the sustainable energy-related research and innovation can bring a revolution in this area. Moreover, by the leveraging current infrastructure, including renewable energy technologies, microgrids, and power-to-gas (P2G) hydrogen systems, the Internet of Things in sustainable energy systems can address challenges in energy security to the community, with a minimal trade-off to environment and culture. In this chapter, the IoT in sustainable energy …


Route Planning For Long-Term Robotics Missions, Christopher Alexander Arend Tatsch Jan 2020

Route Planning For Long-Term Robotics Missions, Christopher Alexander Arend Tatsch

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many future robotic applications such as the operation in large uncertain environment depend on a more autonomous robot. The robotics long term autonomy presents challenges on how to plan and schedule goal locations across multiple days of mission duration. This is an NP-hard problem that is infeasible to solve for an optimal solution due to the large number of vertices to visit. In some cases the robot hardware constraints also adds the requirement to return to a charging station multiple times in a long term mission. The uncertainties in the robot model and environment require the robot planner to account …


The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1 Dec 2019

The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1

Tanzania Journal of Engineering and Technology (TJET)

Worldwide, every day human beings generate millions of tons of Faecal Sludge (FS), which is rich in water, nutrients, energy, and organic compounds. Yet FS is not being managed in a way that permits us to derive value from its reuse, while at the same time, millions of farmers struggle with depleted soils and lack of water. In most of the developing countries, energy for cooking is mainly derived from cutting of trees, either as wood or charcoal. Resource recovery and reuse from FS can create livelihoods, enhance food security, support green economies, reduce waste and contribute to cost recovery …


Resource Allocation And Task Scheduling Optimization In Cloud-Based Content Delivery Networks With Edge Computing, Yang Peng Dec 2019

Resource Allocation And Task Scheduling Optimization In Cloud-Based Content Delivery Networks With Edge Computing, Yang Peng

Operations Research and Engineering Management Theses and Dissertations

The extensive growth in adoption of mobile devices pushes global Internet protocol (IP) traffic to grow and content delivery network (CDN) will carry 72 percent of total Internet traffic by 2022, up from 56 percent in 2017. In this praxis, Interconnected Cache Edge (ICE) based on different public cloud infrastructures with multiple edge computing sites is considered to help CDN service providers (SPs) to maximize their operational profit. The problem of resource allocation and performance optimization is studied in order to maximize the cache hit ratio with available CDN capacity.

The considered problem is formulated as a multi-stage stochastic linear …


Insulation Sensitivity Analysis For An Optimized Fabric Shelter Off-Grid Hybrid Energy System, Jay F. Pearson, Torrey J. Wagner, Steven Schuldt Oct 2019

Insulation Sensitivity Analysis For An Optimized Fabric Shelter Off-Grid Hybrid Energy System, Jay F. Pearson, Torrey J. Wagner, Steven Schuldt

Faculty Publications

During military and disaster relief operations, connecting to an established electrical grid is rarely an option. In these situations, camps consisting of poorly insulated fabric shelters are predominantly powered by inefficient diesel generators that require frequent fuel resupply. In order to reduce the fuel demand of these generators, camps may utilize photovoltaic-battery systems. This paper presents an innovative cost-performance model capable of optimizing solar array size, battery backup system, and shelter insulation type to minimize the operating cost of powering a single fabric shelter. Model performance was evaluated using one year of insolation, weather and energy requirement data from a …


Toolpath Planning Methodology For Multi-Gantry Fused Filament Fabrication 3d Printing, Hieu Trung Bui Aug 2019

Toolpath Planning Methodology For Multi-Gantry Fused Filament Fabrication 3d Printing, Hieu Trung Bui

Graduate Theses and Dissertations

Additive manufacturing (AM) has revolutionized the way industries manufacture and prototype products. Fused filament fabrication (FFF) is one of the most popular processes in AM as it is inexpensive, requires low maintenance, and has high material utilization. However, the biggest drawback that prevents FFF printing from being widely implemented in large-scale production is the cycle time. The most practical approach is to allow multiple collaborating printheads to work simultaneously on different parts of the same object. However, little research has been introduced to support the aforementioned approach. Hence a new toolpath planning methodology is proposed in this paper. The objectives …


Economic Model Predictive Control And Process Equipment: Control-Induced Thermal Stress In A Pipe, Helen Durand Jul 2019

Economic Model Predictive Control And Process Equipment: Control-Induced Thermal Stress In A Pipe, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Recent work on economic model predictive control (EMPC) has indicated that some processes may be operated in a more economically-optimal fashion under a time-varying operating policy than under a steady-state operating policy. However, a concern for time-varying operation is how such a change in operating policy might impact the equipment within which the processes being controlled are carried out. While under steady-state operation, the operating conditions to which equipment would regularly be exposed can be estimated, this would be more difficult to assess thoroughly a priori under time-varying operation. It could be explored whether the EMPC could be made aware …


Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga Jun 2019

Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Research methodology is among the very important part in a research work. It is the heart which describe the activities necessary for the completion of the research work. Research methodology provides a plan of investigation considered to obtain answers to research problems and it depends on the context of application. This paper presents the research methodology adopted when developing Tanzania Secondary Schools e-Learning (TanSSe-L) system, a learning management system (LMS) which was successfully developed through customization of Moodle open source LMS. TanSSe-L system is a context centered platform for secondary schools in Tanzania. TanSSe-L system was developed using a number …


Linking Quality Management Practices With Performance Of Manufacturing Industries In Tanzania, Mussa Iddi Mgwatu Dr. Jun 2019

Linking Quality Management Practices With Performance Of Manufacturing Industries In Tanzania, Mussa Iddi Mgwatu Dr.

Tanzania Journal of Engineering and Technology (TJET)

Local products of manufacturing industries in Tanzania are subjected to intense competition in the markets. Product quality is one of key factors that play a considerable role for manufacturing industries to win the competitive advantage. This paper attempts to analyse the extents of quality management practices (QMP) and manufacturing performance (MP) as well as to examine the linkage between practices and performance. Data was collected from seventy-eight (78) manufacturing industries in Dar es Salaam region using questionnaires comprising of both single-item and multi-item questions. Descriptive statistics was used to quantify the extent of quality management practices and manufacturing performance (MP) …


Improving Power Network Resilience Against Threats, Hamzeh Davarikia Jun 2019

Improving Power Network Resilience Against Threats, Hamzeh Davarikia

LSU Doctoral Dissertations

The work reported in this dissertation aims at developing a practical tool for utility transmission planners to improve the power network resilience against high-impact, low-frequency events (HILF). Such events rarely happen, but when occurred are catastrophic. In this dissertation, we studied the impact of HILF from the static and dynamic point of view and proposed the planning strategy to lower the devastating effect of the HILF.

In the static analysis, we consider the steady-state situation of the power grids and plan to protect the grid’s components, i.e., generators, buses, and transmission lines, to maximize preserving demand in a disastrous situation. …


(Poster) Internal Restoration And Modernization Of A 1948 Wwii Era Jukebox, Miles Furr, Cristiana Olarinre, Joel Carpenter, Elijah Knox, George Ricco, Paul Talaga, Suranga Dharmarathne Mar 2019

(Poster) Internal Restoration And Modernization Of A 1948 Wwii Era Jukebox, Miles Furr, Cristiana Olarinre, Joel Carpenter, Elijah Knox, George Ricco, Paul Talaga, Suranga Dharmarathne

ASEE IL-IN Section Conference

Using Six Sigma guidelines under the sponsorship of The University of Indianapolis in cooperation with the client, Brugh Industrial Engineering, this project is to modernize the functionality and interface of a Rockola Model 1428 Jukebox while maintaining its vintage appeal. The process of modernization includes meeting today's industrial safety standards, incorporating ethernet protocol, and utilizing a programmable logic controller, PLC. The jukebox is a showcase of current automation technology. Lighting has been upgraded from fluorescent and incandescent bulbs to addressable nano pixel LEDs. The amplifier, coin system, and record selection system were revitalized to OEM operation standards. All switches within …


An Integrated Approach For Remanufacturing Job Shop Scheduling With Routing Alternatives., Ling Ling Li, Cong Bo Li, Li Li, Ying Tang, Qing Shan Yang Mar 2019

An Integrated Approach For Remanufacturing Job Shop Scheduling With Routing Alternatives., Ling Ling Li, Cong Bo Li, Li Li, Ying Tang, Qing Shan Yang

Henry M. Rowan College of Engineering Departmental Research

Remanufacturing is a practice of growing importance due to increasing environmental awareness and regulations. However, the stochastic natures inherent in the remanufacturing processes complicate its scheduling. This paper undertakes the challenge and presents a remanufacturing job shop scheduling approach by integrating alternative routing assignment and machine resource dispatching. A colored timed Petri net is introduced to model the dynamics of remanufacturing process, such as various process routings, uncertain operation times for cores, and machine resource conflicts. With the color attributes in Petri nets, two types of decision points, recovery routing selection and resource dispatching, are introduced and linked with places …


36% Reduction In Fuel Resupply Using A Hybrid Generator & Battery System For An Austere Location, David J. Chester, Torrey J. Wagner, Douglas S. Dudis Mar 2019

36% Reduction In Fuel Resupply Using A Hybrid Generator & Battery System For An Austere Location, David J. Chester, Torrey J. Wagner, Douglas S. Dudis

Faculty Publications

The DOD energy policy is to increase energy security resiliency, and mitigate costs in the use and management of energy[1] Forward operating bases (FOBs) are remote, austere base camps that support an operationally defined mission with a limited or no ability to draw from an energy grid and have historically relied on diesel-powered generators for the primary production of energy.[2] Generators are sized to meet a theoretical peak demand, but steady state loads are far below this peak, resulting in under-loaded generators.[3] Under-loaded diesel generators decrease efficiency and increase the need for maintenance, affecting the lifespan of …


Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler Mar 2019

Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler

Master's Theses

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …


On Accounting For Equipment-Control Interactions In Economic Model Predictive Control Via Process State Constraints, Helen Durand Feb 2019

On Accounting For Equipment-Control Interactions In Economic Model Predictive Control Via Process State Constraints, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Traditionally, chemical processes have been operated at steady-state; however, recent work on economic model predictive control (EMPC) has indicated that some processes may be operated in a more economically-optimal fashion under a time-varying operating policy. It is unclear how time-varying operating policies may impact process equipment, which must be investigated for safety and profit reasons. It has traditionally been considered that constraints on process states can be added to EMPC design to prevent the controller from computing control actions which create problematic operating conditions for process equipment. However, no rigorous investigation has yet been performed to analyze whether, when a …


A Sustainable Prototype For Renewable Energy: Optimized Prime-Power Generator Solar Array Replacement, Nathan Thomsen, Torrey J. Wagner, Andrew J. Hoisington, Steven J. Schuldt Jan 2019

A Sustainable Prototype For Renewable Energy: Optimized Prime-Power Generator Solar Array Replacement, Nathan Thomsen, Torrey J. Wagner, Andrew J. Hoisington, Steven J. Schuldt

Faculty Publications

Remote locations such as disaster relief camps, isolated arctic communities, and military forward operating bases are disconnected from traditional power grids forcing them to rely on diesel generators with a total installed capacity of 10,000 MW worldwide. The generators require a constant resupply of fuel, resulting in increased operating costs, negative environmental impacts, and challenging fuel logistics. To enhance remote site sustainability, planners can develop stand-alone photovoltaic-battery systems to replace existing prime power generators. This paper presents the development of a novel cost-performance model capable of optimizing solar array and Li-ion battery storage size by generating tradeoffs between minimizing initial …