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Articles 57811 - 57840 of 197998

Full-Text Articles in Engineering

Research Of Kinetic Characteristics Of The Process Of Decomposition Of Zinc Concentrate With Hydrochloric Acid, Rosilov Mansur, Deng Tianlong, Usmanov Ilham, Samadiy Murodjon Jun 2020

Research Of Kinetic Characteristics Of The Process Of Decomposition Of Zinc Concentrate With Hydrochloric Acid, Rosilov Mansur, Deng Tianlong, Usmanov Ilham, Samadiy Murodjon

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was the theoretical justification of the kinetic characteristics of the process of producing zinc chloride from zinc concentrate of the Khandiza deposit. For this, the effect of temperature and duration of the process of autoclave zinc extraction in a 28% hydrochloric acid solution was studied at a ratio of Zn: HCI = 1:1.1. Variable parameters were the temperature of 70, 80 and 90 °C and the duration of the leaching process of 6, 8 and 10 hours. The optimal parameters for the production of zinc chloride were determined.


The Study Of The Component Composition Of The Reaction Mixture Containing Formaldehyde Reaction Products, Hurramov Lochinbek, Alimukhamedova Nozima, Adilov Ravshan, Alimukhamedov Muzafar Jun 2020

The Study Of The Component Composition Of The Reaction Mixture Containing Formaldehyde Reaction Products, Hurramov Lochinbek, Alimukhamedova Nozima, Adilov Ravshan, Alimukhamedov Muzafar

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the effect of the conditions of the reaction of monoethanolamine (Meol) with formaldehyde (FD) on the composition of the reaction mixture. Interaction of monoethanolamine with formaldehyde leads to the formation of N,N’,N”-tris(β-oxyethyl) hexahydro-S-triazine or N,N-bisoxazolidine. The type of final product was determined by the conditions of the reaction and the molar ratio of aminoalcohol:formaldehyde. The chromatogram of the vacuum-distilled final product obtained at the molar ratio of monoethanolamine:formaldehyde=1:1 shows on an individual compound with a retention time of 4.173 s. With increase in the molar ratio of monoethanolamine:formaldehyde=1: 2, the final product …


Obtaining Microcrystalline Cellulose From Melon Crops And Studying Its Structure, Umarova Vasila, Mardonov Asror, Khamdamova Dilnoza, Akmalova Guzal Jun 2020

Obtaining Microcrystalline Cellulose From Melon Crops And Studying Its Structure, Umarova Vasila, Mardonov Asror, Khamdamova Dilnoza, Akmalova Guzal

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was to obtain microcrystalline cellulose from gourds. Cellulose was isolated from the stems of watermelon and pumpkin by acid and alkaline heat treatment. Microcrystalline cellulose was obtained from cellulose by hydrolysis. Cellulose was hydrolyzed in a mixture of sulfuric acid and hydrogen peroxide. The optical parameters of the microcrystalline cellulose sample, ash content, bulk density, water swelling, and moisture sorption were determined. The structural features of the obtained microcrystalline cellulose were studied by IR spectroscopy. The functional groups present under various conditions for the production of microcrystalline cellulose were determined. The influence of the duration …


Radiopaque Activity Of Iodine Containing Methylene-Bis-Carbamate, Baltabaev Ubaydulla, Djuraev Abdukahhor, Abduvakilov Jahongir, Abdullaeva Matluba Jun 2020

Radiopaque Activity Of Iodine Containing Methylene-Bis-Carbamate, Baltabaev Ubaydulla, Djuraev Abdukahhor, Abduvakilov Jahongir, Abdullaeva Matluba

CHEMISTRY AND CHEMICAL ENGINEERING

Considering that many derivatives of bis carbamates have different biological activity, it was intuitive to produce a targeted synthesis of new derivatives of bis carbamates by the interaction of hexamethylene diisocyanate with 3,5-diode-4-hydroxybenzoic acid and 2,4,6-triiodophenol (1: 2 mol, respectively) in freshly distilled dry pyridine at 95-110 оC for 6 hours, the corresponding derivatives were obtained - methylene bis carbamates. Experimental studies have been conducted to identify the acute toxicity and radiopaque properties of the synthesized new N, -hexamethylene bis (2,6-diode-4-carboxyphenylcarbamate).


Modification Of Lithium Lubricants, Azimova Shodiyakhon, Arslanov Sharafutdin, Aripdjanov Oybek, Azimov Dilmurod Jun 2020

Modification Of Lithium Lubricants, Azimova Shodiyakhon, Arslanov Sharafutdin, Aripdjanov Oybek, Azimov Dilmurod

CHEMISTRY AND CHEMICAL ENGINEERING

The aim is to study the effect of the presence of free alkalis and acids on the properties of the complex lithium greases and the choice of the optimal dispersion medium, which provides the required physicochemical characteristics of the developed grease. The dispersed phase of lithium greases studied in the polyalphaolefin oils media. It was found that the use of a mixture of polyalphaolefin oil-4 and polyalphaolefin oil-40 as a percentage of 23/77 with a total content of 83.0% provides a relatively low effective viscosity of the lubricant at low temperatures and a relatively high tensile strength at high temperature.


Effective Oil Extraction From Bombyx Mori Silkworm Pupae And Its Structural Characteristics, Avazova Oynavod, Yugai Sveta, Rashidova Sayora Jun 2020

Effective Oil Extraction From Bombyx Mori Silkworm Pupae And Its Structural Characteristics, Avazova Oynavod, Yugai Sveta, Rashidova Sayora

CHEMISTRY AND CHEMICAL ENGINEERING

The conditions for the effective isolation of oil from the silkworm Bombyx mori pupae, based on the extraction of extracted oil with organic reagents, have been studied. The quantitative content of oil was determined in the samples. It is revealed that the oils extracted using gasoline have a high fat-wax composition compared with ethyl alcohol and hexane. When dried pupae processed with gasoline, it is possible to extract up to 16% of fatty substances as much as possible. Physical-chemical characteristics of the oil from silkworm pupae are characterized by high quality indicators. In particular, the presence of unsaturated fatty acids …


Composition Of Liquid Paraffins For Flotation Enrichment Of Potassium Chloride, Vaqqosov Sobir, Xolmuratov Shamsitdin, Buxarov Shuhrat, Kodirov Orifjon Jun 2020

Composition Of Liquid Paraffins For Flotation Enrichment Of Potassium Chloride, Vaqqosov Sobir, Xolmuratov Shamsitdin, Buxarov Shuhrat, Kodirov Orifjon

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is to determine the source of liquid paraffins from secondary products of the local chemical industry, compare the performance properties and use the resulting products as apolar co-reagents in silvinite flotation. The experiments were conducted with secondary used hexane and pyrocondensation. To improve the efficiency of flotation, the dependences of the order of reagent’s supply into the process and the time of action were studied. Experiments have shown that when adding tetradecane and pentadecane in an amount of 2.5 to 7.5% to hexane liquid paraffins, it is possible to reduce the tail of KCl to …


Influence Of Technological Parameters On The Chemical Composition Of Calcium Polyphosphates From Phosphorites Central Kyzylkum, Ulugberdieva Ziyada, Khujamberdiev Sherzod, Mirzakulov Kholtura, Usmanov Ilkham Jun 2020

Influence Of Technological Parameters On The Chemical Composition Of Calcium Polyphosphates From Phosphorites Central Kyzylkum, Ulugberdieva Ziyada, Khujamberdiev Sherzod, Mirzakulov Kholtura, Usmanov Ilkham

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research was to study the effect of temperature, the ratio of P2O5EPA:P2O5PRM and the duration of calcination on the content of various forms of P2O5 in calcium polyphosphate. The effect of calcination temperature from 150 to 300 °C, the ratio of P2O5EPA:P2O5FRM from 2,15 to 4,50 and the duration of the process from 20 to 120 minutes on the changes in various forms of P2O5 were studied. It was shown that with increasing temperature to 200-250 °C the content of the total (ortho + poly) assimilable form of Р2О5 increases and then decreases, passing through a …


Bases Of Development Of Technologies Of Synthesis Of Oxide Materials In Big Solar Furnace (Parkent), Gulamova Dilbara, Baxronov Khayot, Bobokhulov Sirojiddin, Eshonkulov Elyor Jun 2020

Bases Of Development Of Technologies Of Synthesis Of Oxide Materials In Big Solar Furnace (Parkent), Gulamova Dilbara, Baxronov Khayot, Bobokhulov Sirojiddin, Eshonkulov Elyor

CHEMISTRY AND CHEMICAL ENGINEERING

The advantages of synthesis of complex oxide compounds by solar energy, the possibility of obtaining highly textured nano materials are shown. The development of heliomaterial science, aimed at the synthesis of new materials, is inextricably linked with the use of effective optical energy systems. On the example of obtaining superconducting materials of nominal composition Bi1.7Pb0.3Sr2Ca(n-1)CunOy (n = 3-20), optimization of the parameters of the optical-energy system of the Big Solar Furnace (Parkent) is shown. The ideology of developing heliotechnology for the synthesis of inorganic materials in a solar furnace is presented. The properties of a superconducting material of nominal Bi1.7Pb0.3Sr2Ca(n1)CunOy …


Sustainability Action Tracker, Gladys Hilerio, Isabelle Termaat, Patricia Ornelas Jauregui Jun 2020

Sustainability Action Tracker, Gladys Hilerio, Isabelle Termaat, Patricia Ornelas Jauregui

Computer Science and Engineering Senior Theses

The Center for Sustainability at Santa Clara University is actively looking for ways to involve students in sustainable actions and accountability. With our help, they would like to create a site where students and faculty may track their sustainable behavior. This site will provide users with all the information they need to live a sustainable life, and include milestones in the form of progress bars and badges. The Center for Sustainability will be able to collect the data from this site to evaluate the progress of our university as well as the success of the site. Our motivation for this …


Small Molecule Drug Release Form In Situ Forming Degradable Scaffolds Incorporating Hydrogels And Bioceramic Microparticles, David A. Puleo, Todd A. Milbrandt, J. Zach Hilt, Paul Fisher, Vishwas Talwalkar Jun 2020

Small Molecule Drug Release Form In Situ Forming Degradable Scaffolds Incorporating Hydrogels And Bioceramic Microparticles, David A. Puleo, Todd A. Milbrandt, J. Zach Hilt, Paul Fisher, Vishwas Talwalkar

Biomedical Engineering Faculty Patents

The present invention relates to an injectable system combining a hydrogel, a bioceramic and a degradable matrix that provides for sustained drug delivery and structural support to recovering tissue, such as bone and the periodontium.


A Systems-Level Approach To The Design, Evaluation, And Optimization Of Electrified Transportation Networks Using Agent-Based Modeling, Landon Clark Willey Jun 2020

A Systems-Level Approach To The Design, Evaluation, And Optimization Of Electrified Transportation Networks Using Agent-Based Modeling, Landon Clark Willey

Theses and Dissertations

Rising concerns related to the effects of traffic congestion have led to the search for alternative transportation solutions. Advances in battery technology have resulted in an increase of electric vehicles (EVs), which serve to reduce the impact of many of the negative consequences of congestion, including pollution and the cost of wasted fuel. Furthermore, the energy-efficiency and quiet operation of electric motors have made feasible concepts such as Urban Air Mobility (UAM), in which electric aircraft transport passengers in dense urban areas prone to severe traffic slowdowns. Electrified transportation may be the solution needed to combat urban gridlock, but many …


Usu Engineering Professor Named Ieee Distinguished Lecturer, Usu College Of Engineering Jun 2020

Usu Engineering Professor Named Ieee Distinguished Lecturer, Usu College Of Engineering

College of Engineering News

June 16, 2020 — Utah State University Professor Rose Hu has again been named to a class of distinguished lecturers within the Institute of Electrical and Electronics Engineers, known as IEEE.


Study And Characterization Of Conductive Elastomers For Biomedical Applications, Hadis Gharacheh Jun 2020

Study And Characterization Of Conductive Elastomers For Biomedical Applications, Hadis Gharacheh

Theses and Dissertations

Health issues have always been one of humankind's biggest challenges. Over the last century, there has been significant and monumental progress in health and biomedical science, with the end goal of alleviating and eliminating illnesses and ailments. For developing biomedical devices, polymers and elastomers group among other types of biomaterials have been highlighted to be used due to high flexibility, stability, biocompatibility, and mechanical and rheological characteristics. In this work, the characterization of acrylated poly glycerol_sebacate (PGSA) polymer conjugated with bio ionic liquid (BIL) was investigated. Results showed high biocompatibility, high printability with tunable mechanical, adhesive, and conductivity properties. For …


Electrospun Nanofibrous Membrane Based Glucose Sensor With Integration Of Potentiostat Circuit, Kavyashree Puttananjegowda Jun 2020

Electrospun Nanofibrous Membrane Based Glucose Sensor With Integration Of Potentiostat Circuit, Kavyashree Puttananjegowda

USF Tampa Graduate Theses and Dissertations

Although wearable and portable biomedical devices are the pillar of modern and smart societies, a large portion the device infrastructure is still under development, operates with poor monitoring and automation, and lacks sufficient communication among components. Moreover, demand for wearable bio-medical devices is expected to increase in the coming years. This situation presents a unique opportunity for electrical engineers to design novel strategies that allow point-of-care diagnostics to satisfy the increasing demand of wearable bio-medical devices. For example, in the medical field there is a rising diabetic population base, high demand for miniature and low-power diagnostic devices, and the need …


Performance Of A Full-Scale Rammed Aggregate Pier Group In Silty Sand Based On Blast-Induced Liquefaction Testing In Emilia-Romagna, Italy, Paul Joseph Walsh Andersen Jun 2020

Performance Of A Full-Scale Rammed Aggregate Pier Group In Silty Sand Based On Blast-Induced Liquefaction Testing In Emilia-Romagna, Italy, Paul Joseph Walsh Andersen

Theses and Dissertations

To investigate the liquefaction mitigation capability of Rammed Aggregate Piers® (RAP) in silty sand, blast liquefaction testing was performed at a soil profile treated with a full-scale RAP group relative to an untreated soil profile. The RAP group consisted of 16 piers in a 4x4 arrangement at 2 m center-to-center spacing extending to a depth of 9.5 m. Blasting around the untreated area induced liquefaction (ru ≈1.0) from 3 m to 11 m depth, producing several large sand boils, and causing settlement of 10 cm. In contrast, installation of the RAP group reduced excess pore water pressure (ru ≈0.75), eliminated …


Analysis Of Performance Measures Of Traffic Incident Management In Utah, Mitchell Gregory Hadfield Jun 2020

Analysis Of Performance Measures Of Traffic Incident Management In Utah, Mitchell Gregory Hadfield

Theses and Dissertations

In 2009 the Federal Highway Administration published a report regarding a Focus States Initiative that had been conducted with 11 states to discuss the development of national Traffic Incident Management (TIM) standards. Performance measures were defined, and a national TIM dashboard created, but very little data has been added to the dashboard since. In this research study, performance measures of the Utah Department of Transportation (UDOT) TIM program were analyzed. Data availability was first assessed to determine whether these performance measures could be calculated. It was determined that crash response data available from the Utah Highway Patrol (UHP) could be …


Evaluating The Impacts Of Hurricane Maria On The Residential Construction Industry In Puerto Rico And The Effectiveness Of Reconstruction Efforts, M. Bradley Wells Jun 2020

Evaluating The Impacts Of Hurricane Maria On The Residential Construction Industry In Puerto Rico And The Effectiveness Of Reconstruction Efforts, M. Bradley Wells

Theses and Dissertations

In September of 2017, Hurricane Irma and Hurricane Maria, both category 5 hurricanes, swept across the Caribbean, including the U.S. Territory island of Puerto Rico. These two storms, particularly Hurricane Maria, caused catastrophic damages from high winds and flooding to the island paradise. This research investigates the direct effects that Hurricane Maria had on the residential construction industry within Puerto Rico and evaluates how to better prioritize and manage these types of efforts in the future. This research was initiated to identify challenges and opportunities that have been encountered within the Puerto Rican construction industry during the first year of …


In Vivo Biosynthesis Of Inorganic Nanomaterials Using Eukaryotes - A Review, Ashiqur Rahman, Julia Lin, Francisco E. Jaramillo, Dennis A. Bazylinski, Clayton Jeffryes, Si Amar Dahoumane Jun 2020

In Vivo Biosynthesis Of Inorganic Nanomaterials Using Eukaryotes - A Review, Ashiqur Rahman, Julia Lin, Francisco E. Jaramillo, Dennis A. Bazylinski, Clayton Jeffryes, Si Amar Dahoumane

Life Sciences Faculty Research

Bionanotechnology, the use of biological resources to produce novel, valuable nanomaterials, has witnessed tremendous developments over the past two decades. This eco-friendly and sustainable approach enables the synthesis of numerous, diverse types of useful nanomaterials for many medical, commercial, and scientific applications. Countless reviews describing the biosynthesis of nanomaterials have been published. However, to the best of our knowledge, no review has been exclusively focused on the in vivo biosynthesis of inorganic nanomaterials. Therefore, the present review is dedicated to filling this gap by describing the many different facets of the in vivo biosynthesis of nanoparticles (NPs) using living eukaryotic …


Sdhome: Securing Fast Home Networks, Christopher Batula, Holden Gordon, Tianyi Zhao Jun 2020

Sdhome: Securing Fast Home Networks, Christopher Batula, Holden Gordon, Tianyi Zhao

Computer Science and Engineering Senior Theses

Distributed denial of service (DDoS) is a highly discussed network attack in Software Defined Networks. Attacks such as the Mirai Botnet threaten to compromise portion of large networks, including home users. Today, corporations secure their network using enterprise level software to protest their network from DDoS attacks . But their solutions are meant for large networks and depend on expensive hardware. There are few security solutions for home users and most are expensive or require a subscription for full protection. In this paper, we propose a new solution in the form of a plug and play device that will allow …


Nonlinear Breaking-Wave Characteristics In Lagrangian Coordinates, Wen-Jer Tseng, Chia-Yan Cheng Jun 2020

Nonlinear Breaking-Wave Characteristics In Lagrangian Coordinates, Wen-Jer Tseng, Chia-Yan Cheng

Journal of Marine Science and Technology–Taiwan

This paper presents a theoretical investigation of nonlinear surface-wave propagation over a sloping bottom. For a problem with nonlinear surface-wave propagation over a sloping bottom, a perturbation method is first used to find the analytical solution in order to derive the third order terms for the bottom slope  and the wave steepness  in the Eulerian system. Then, by transforming the flow field solution from the Eulerian system into the Lagrangian system, a more accurate wave profile is identified. By using the kinematic stability parameter, new theoretical breaking-wave characteristics are derived. The theoretical solutions are then compared with those …


Share Buybacks And Income Inequality, Thomas Power Jun 2020

Share Buybacks And Income Inequality, Thomas Power

Articles

Should you care what companies do with their profits? Two U.S. democratic senators, Chuck Schumer and Bernie Sanders, in an article in the New York Times, argue that we should all care because what companies do with their profits can damage the economy and jobs.


Numerical Analyses Of Pile Foundation For Support Structure Of Offshore Wind Turbine At Changhua Coast In Taiwan, Der-Guey Lin, Sheng-Hsien Wang, Jui-Ching Chou, Cheng-Yu Ku, Lien-Kwei Chien Jun 2020

Numerical Analyses Of Pile Foundation For Support Structure Of Offshore Wind Turbine At Changhua Coast In Taiwan, Der-Guey Lin, Sheng-Hsien Wang, Jui-Ching Chou, Cheng-Yu Ku, Lien-Kwei Chien

Journal of Marine Science and Technology–Taiwan

This study investigates the bearing capacities of group pile foundation (jacket foundation) installed on the seabed of offshore wind farm (OWF) at the Changhua coast of Western Taiwan for the jacket support structure of offshore wind turbine (OWT) using three-dimensional (3-D) finite element method (FEM). The jacket foundations are subjected to a combined Vertical-Horizontal-Moment (V-H-M) loading for the operational period. The responses of installed group pile foundations are investigated under the combined loading in marine silty sand-low plasticity silt & clay (SM-ML-CL) layers determined by 19 offshore boring logs. The validity of numerical procedures was verified by a large-scale lateral …


Solar Photovoltaic Considerations For Operational And Warfighter Support Capabilities, Dylan Martin-Abood, Douglas Dudis, Torrey J. Wagner Jun 2020

Solar Photovoltaic Considerations For Operational And Warfighter Support Capabilities, Dylan Martin-Abood, Douglas Dudis, Torrey J. Wagner

Faculty Publications

This work highlights the fundamental mechanisms and historical perspective for military PV technology applications and addresses the operational considerations for effectively deploying PV technology. PV materials, structures and architectures have matured into competitive and readily available energy technologies based on their levelized cost of energy (LCOE). However, enhancing warfighting capabilities requires attention to systems considerations beyond cost per watt or LCOE. While PV is impractical for fighters and bombers as it can meet less than 1% of their power requirements, there are numerous areas that could benefit from the application of PV technology. For example, installing PV arrays on all …


Investigation Of The Process Of Self-Discharge Acid Batteries, Asilbek Kiryigitovich Mamatkulov, Eldor Ikromovich Ruzmatov, Gulniso Yulchievna Zhumaeva, Furkat Ilyasovich Erkabaev Jun 2020

Investigation Of The Process Of Self-Discharge Acid Batteries, Asilbek Kiryigitovich Mamatkulov, Eldor Ikromovich Ruzmatov, Gulniso Yulchievna Zhumaeva, Furkat Ilyasovich Erkabaev

Chemical Technology, Control and Management

In this study, investigations were conducted on the process of self-discharge of acidic car batteries. The dependence of battery discharge on environmental temperature has been studied. It was found that the self-discharge of batteries increases by up to 60% over 12 months when the temperature rises from +100C to +400С. Replacing the tin in the electrode alloy with a more electronegative metal has been shown to reduce the self-discharge process by up to 2% per month. Because, the self-discharge of electrode batteries made of lead-calcium alloy is relatively low, the consumption of working fluid is relatively …


Mathematical Modeling Of Thermal Processes Of Traction Asynchronous Engines For Diagnosis And Control Of Their Technical Condition, Nilufar Rabbanaqulovna Avezova, Javharbek Sulton Ugli Fayzullayev Jun 2020

Mathematical Modeling Of Thermal Processes Of Traction Asynchronous Engines For Diagnosis And Control Of Their Technical Condition, Nilufar Rabbanaqulovna Avezova, Javharbek Sulton Ugli Fayzullayev

Chemical Technology, Control and Management

Mathematical models of thermal processes of traction asynchronous motors are developed. A traction asynchronous motor is considered as a thermal system consisting of three bodies (stator winding, stator magnetic core and rotor), which take into account the heat exchange not only between the corresponding bodies, but also the heat exchange between each body and the environment. It is shown that the steady excess of the stator winding temperature of a traction asynchronous motor depends on the multiplicity of the stator winding current, the coefficient of electrical energy loss, and also on the temperature coefficient of the resistance of the winding …


Theory, Fabrication, And Characterization Of Perovskite Phototransistor, Fatemeh Khorramshahi Jun 2020

Theory, Fabrication, And Characterization Of Perovskite Phototransistor, Fatemeh Khorramshahi

USF Tampa Graduate Theses and Dissertations

In recent years, there has been a significant interest in making electronic devices with low-cost techniques and materials for both industrial and medical applications. Methylammonium lead iodide perovskite (MAPbI3) is one of the novel materials which has drawn much attention owing to its outstanding optical and electrical properties along with inexpensive, simple, and easy fabrication methods. In this work, the feasibility of using microfluidic device fabrication techniques on making a perovskite phototransistor has been studied. The fabrication method well addresses challenges such as lead toxicity and instability.

In the first step, mechanical micromachining and laser engraving were employed to make …


Assessment Of Dynamic Response Of Offshore Jacket Platforms Subjects To Random Waves, Xiaoshuang Han, Weiliang Qiao, Bo Zhou Jun 2020

Assessment Of Dynamic Response Of Offshore Jacket Platforms Subjects To Random Waves, Xiaoshuang Han, Weiliang Qiao, Bo Zhou

Journal of Marine Science and Technology–Taiwan

This paper presents a simplified approach to analyze the dynamic response of offshore jacket platform based on Timoshenko beam theory. In the study, the jacket platform is simulated as a non-uniform cantilever beam structure subjects to random waves. The assessment of dynamic performance is based on the power spectral densities, variances and spectral moments due to wave spectrum. A combination of Pseudo-excitation and Ritz method is proposed and adopted, such as the dynamic characteristics of the jacket platform can be solved more efficiently without a need to examine the modes of vibration. The proposed analytical method also provides a more …


Research Properties Of Solving Problems Of Parametric Optimization, Dilnoz Tulkunovna Muhamediyeva Jun 2020

Research Properties Of Solving Problems Of Parametric Optimization, Dilnoz Tulkunovna Muhamediyeva

Chemical Technology, Control and Management

A model of parametric optimization with fuzzy initial information is constructed. The conditions and areas of application of the main methods of the theory of fuzzy sets in studies of parametric optimization are determined. A connection is established between the stability of parametric optimization problems and fuzzy optimization problems. An algorithm for solving problems by the method of parametric programming is developed for fuzzy given initial information. The admissible region of the parametric programming problem and the value of its objective function at each point of this region depend on the parameter t. A description of the method for solving …


Constraint-Type Fictitious Time Integration Method For Solving Non-Linear Multi-Dimensional Elliptic Partial Differential Equations, Yung-Wei Chen, Chein-Shan Liu, Yen-Shen Chang, Jiang-Ren Chang Jun 2020

Constraint-Type Fictitious Time Integration Method For Solving Non-Linear Multi-Dimensional Elliptic Partial Differential Equations, Yung-Wei Chen, Chein-Shan Liu, Yen-Shen Chang, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

In this paper, we propose a constraint-type fictitious time integration method (FTIM) for solving multi-dimensional non-linear elliptic-type partial differential equations. Based on the variable transformation of FTIM, the original governing equation is transformed into a new parabolic equation of an evolution type by introducing a space-time variable, and a new time integration direction is obtained. However, the space-time variable depends on the governing equation, boundary condition and fictitious time variable, especially due to the nonlinear effect. Previous studies have not discussed the definition of these nonlinear parameter problems, which may result in severe numerical instability and inaccuracy. To completely overcome …