The Research on Damage and Failture Mechanism of Drivepipe under Seismic Load

2011 ◽  
Vol 374-377 ◽  
pp. 2096-2099
Author(s):  
Xiang Cao Zhi ◽  
Jia Zhu Xue ◽  
Xiu Li Cao
Keyword(s):  
Mathematical Model ◽  
Mechanical Model ◽  
Strain Analysis ◽  
Seismic Load ◽  
Stress And Strain ◽  
Mechanical Method ◽  
Mechanism Research ◽  
Geological Factors ◽  
Stress Damage ◽  
The Impact

Geological factors and engineering factors is a major factor to damage, the drivepipe deformation under pressure seismic load which used to establish mathematical model of the mechanical model can calculated the stress and strain analysis of the casing. The drivepipe damage to this article on the mechanism research on the mechanical model of drivepipe analysis under Seismic load, based on the drivepipe through the focus on the impact and stress damage to the mechanical method of drivepipe deformation studies, and the models of a drivepipe failure mechanism of the mechanical and mathematical are established, which will scientifically, accurately predict the damaged drivepipe.

scholarly journals Mathematical model for determining the limit load capacity of an energy-intensive profile of class 4

2018 ◽  
Vol 19 (9) ◽  
pp. 133-136
Author(s):  
Dominik Gałdyński
Keyword(s):  
Mathematical Model ◽  
Cross Section ◽  
Load Capacity ◽  
Limit Load ◽  
Stress And Strain ◽  
Mathematical Apparatus ◽  
Load Bearing Capacity ◽  
Automotive Body ◽  
The Impact

The article discusses the process of stress and strain changes for an energy-intensive profile with a square cross-section as a result of axial compression, expressed using a mathematical apparatus that allows determination of the load-bearing capacity of such a profile, the use of which in the form of stringers is found in modern automotive body constructions . Elements, such as the so-called a zone of controlled crumpling, taking over part of the impact energy, at the same time being responsible for the progressive nature of the deformation of this area.

scholarly journals Vibration Control of Load for Jib Crane by using PID Controller

2020 ◽  
Vol 27 (3) ◽  
pp. 89-96
Author(s):  
Fares Abbas ◽  
Tawfik Al Massoud
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Vibration Control ◽  
Mechanical Model ◽  
Pid Controller ◽  
Integrated Production ◽  
Production Processes ◽  
Matlab Program ◽  
The Impact ◽  
The Mathematical Model

Jib Crane is a type of machinery used mainly to raise or lower materials or heavy objects and to carrying them to other places. It is used in construction and in the installation of large machines such as wind turbines and harbors, and is an essential component of integrated production processes. Because of the large loads carried by these cranes it became necessary to know their behavior before investment by studying their movements and studying the vibration of payloads and work to reduce them as much as possible and thus prolong the life of the crane components and increase their efficiency. Hence the need to design a control system to dampen load vibration to reduce the impact of dynamics affecting the parts of the crane. In this research, the mathematical model similar to the mechanical model of the crane was prepared and solving the model using MATLAB program, and then design a proportional integral differential controller for jib crane

The Impact of Light Polarisation on Light Field of Scenes with Multiple Reflections

2020 ◽  
pp. 108-115 ◽  
Author(s):  
Vladimir P. Budak ◽  
Anton V. Grimaylo
Keyword(s):  
Mathematical Model ◽  
Light Field ◽  
Global Illumination ◽  
Multiple Reflections ◽  
Software Environment ◽  
The Monte Carlo Method ◽  
Mueller Matrices ◽  
Volume Integration ◽  
The Impact

The article describes the role of polarisation in calculation of multiple reflections. A mathematical model of multiple reflections based on the Stokes vector for beam description and Mueller matrices for description of surface properties is presented. On the basis of this model, the global illumination equation is generalised for the polarisation case and is resolved into volume integration. This allows us to obtain an expression for the Monte Carlo method local estimates and to use them for evaluation of light distribution in the scene with consideration of polarisation. The obtained mathematical model was implemented in the software environment using the example of a scene with its surfaces having both diffuse and regular components of reflection. The results presented in the article show that the calculation difference may reach 30 % when polarisation is taken into consideration as compared to standard modelling.

Mathematical Model of the Effective Properties of a Fiber Reinforced Composite with a Linearly Graded Transition Zone

2010 ◽  
Vol 38 (4) ◽  
pp. 286-307
Author(s):  
Carey F. Childers
Keyword(s):  
Mathematical Model ◽  
Transition Zone ◽  
Effective Properties ◽  
Local Stress ◽  
Stress And Strain ◽  
Fiber Reinforced ◽  
Strain Fields ◽  
Shear Moduli ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite

Abstract Tires are fabricated using single ply fiber reinforced composite materials, which consist of a set of aligned stiff fibers of steel material embedded in a softer matrix of rubber material. The main goal is to develop a mathematical model to determine the local stress and strain fields for this isotropic fiber and matrix separated by a linearly graded transition zone. This model will then yield expressions for the internal stress and strain fields surrounding a single fiber. The fields will be obtained when radial, axial, and shear loads are applied. The composite is then homogenized to determine its effective mechanical properties—elastic moduli, Poisson ratios, and shear moduli. The model allows for analysis of how composites interact in order to design composites which gain full advantage of their properties.

The Impact of L-Carnitine and Coenzyme Q10 as Protection Against Busulfan-Oxidative Stress in the Liver of Adult Rats

2020 ◽  
Vol 10 (5) ◽  
pp. 578-586
Author(s):  
Areeg M. Abdelrazek ◽  
Shimaa A. Haredy
Keyword(s):  
Oxidative Stress ◽  
Coenzyme Q10 ◽  
Protective Role ◽  
Albino Rats ◽  
Distilled Water ◽  
Negative Effects ◽  
Adult Rats ◽  
Stress Damage ◽  
The Impact ◽  
Liver Tissues

Background: Busulfan (Bu) is an anticancer drug with a variety of adverse effects for cancer patients. Oxidative stress has been considered as a common pathological mechanism and it has a key role in the initiation and progression of liver injury by Bu. Aim: The study aimed to evaluate the antioxidant impact of L-Carnitine and Coenzyme Q10 and their protective role against oxidative stress damage in liver tissues. Methods and Material: Thirty-six albino rats were divided equally into six groups. G1 (con), received I.P. injection of DMSO plus 1 ml of distilled water daily by oral gavages; G2 (Bu), received I.P. injection of Bu plus 1 ml of the distilled water daily; G3 (L-Car), received 1 ml of L-Car orally; G4 (Bu + L-Car) received I.P. injection of Bu plus 1 ml of L-Car, G5 (CoQ10) 1 ml of CoQ10 daily; and G6 (Bu + CoQ10) received I.P. injection of Bu plus 1 ml of CoQ10 daily. Results: The recent data showed that Bu induced significant (P<0.05) elevation in serum ALT, AST, liver GSSG, NO, MDA and 8-OHDG, while showing significant (P<0.05) decrease in liver GSH and ATP. On the other hand, L-Carnitine and Coenzyme Q10 ameliorated the negative effects prompted by Bu. Immunohistochemical expression of caspase-3 in liver tissues reported pathological alterations in Bu group while also showed significant recovery in L-Car more than CoQ10. Conclusion: L-Car, as well as CoQ10, can enhance the hepatotoxic effects of Bu by promoting energy production in oxidative phosphorylation process and by scavenging the free radicals.

Analyzing the Impact of Healthy Behavior on Weight Change with a Provable Mathematical Model (Preprint)

2020 ◽  
Author(s):  
Ayan Chatterjee ◽  
Ram Bajpai ◽  
Pankaj Khatiwada
Keyword(s):  
Physical Activity ◽  
Mathematical Model ◽  
Health Behavior ◽  
Weight Change ◽  
Simulated Data ◽  
Negative Behavior ◽  
Healthy Behavior ◽  
Healthy Habits ◽  
Lifestyle Diseases ◽  
The Impact

BACKGROUND Lifestyle diseases are the primary cause of death worldwide. The gradual growth of negative behavior in humans due to physical inactivity, unhealthy habit, and improper nutrition expedites lifestyle diseases. In this study, we develop a mathematical model to analyze the impact of regular physical activity, healthy habits, and a proper diet on weight change, targeting obesity as a case study. Followed by, we design an algorithm for the verification of the proposed mathematical model with simulated data of artificial participants. OBJECTIVE This study intends to analyze the effect of healthy behavior (physical activity, healthy habits, and proper dietary pattern) on weight change with a proposed mathematical model and its verification with an algorithm where personalized habits are designed to change dynamically based on the rule. METHODS We developed a weight-change mathematical model as a function of activity, habit, and nutrition with the first law of thermodynamics, basal metabolic rate (BMR), total daily energy expenditure (TDEE), and body-mass-index (BMI) to establish a relationship between health behavior and weight change. Followed by, we verified the model with simulated data. RESULTS The proposed provable mathematical model showed a strong relationship between health behavior and weight change. We verified the mathematical model with the proposed algorithm using simulated data following the necessary constraints. The adoption of BMR and TDEE calculation following Harris-Benedict’s equation has increased the model's accuracy under defined settings. CONCLUSIONS This study helped us understand the impact of healthy behavior on obesity and overweight with numeric implications and the importance of adopting a healthy lifestyle abstaining from negative behavior change.

scholarly journals Nanofluid flow containing carbon nanotubes with quartic autocatalytic chemical reaction and Thompson and Troian slip at the boundary

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Muhammad Ramzan ◽  
Jae Dong Chung ◽  
Seifedine Kadry ◽  
Yu-Ming Chu ◽  
Muhammad Akhtar
Keyword(s):  
Mathematical Model ◽  
Carbon Nanotubes ◽  
Drag Force ◽  
Chemical Reaction ◽  
Slip Velocity ◽  
Volume Fraction ◽  
Surface Drag ◽  
Nanofluid Flow ◽  
Velocity Parameter ◽  
The Impact

Abstract A mathematical model is envisioned to discourse the impact of Thompson and Troian slip boundary in the carbon nanotubes suspended nanofluid flow near a stagnation point along an expanding/contracting surface. The water is considered as a base fluid and both types of carbon nanotubes i.e., single-wall (SWCNTs) and multi-wall (MWCNTs) are considered. The flow is taken in a Dacry-Forchheimer porous media amalgamated with quartic autocatalysis chemical reaction. Additional impacts added to the novelty of the mathematical model are the heat generation/absorption and buoyancy effect. The dimensionless variables led the envisaged mathematical model to a physical problem. The numerical solution is then found by engaging MATLAB built-in bvp4c function for non-dimensional velocity, temperature, and homogeneous-heterogeneous reactions. The validation of the proposed mathematical model is ascertained by comparing it with a published article in limiting case. An excellent consensus is accomplished in this regard. The behavior of numerous dimensionless flow variables including solid volume fraction, inertia coefficient, velocity ratio parameter, porosity parameter, slip velocity parameter, magnetic parameter, Schmidt number, and strength of homogeneous/heterogeneous reaction parameters are portrayed via graphical illustrations. Computational iterations for surface drag force are tabulated to analyze the impacts at the stretched surface. It is witnessed that the slip velocity parameter enhances the fluid stream velocity and diminishes the surface drag force. Furthermore, the concentration of the nanofluid flow is augmented for higher estimates of quartic autocatalysis chemical.

scholarly journals Modelling the impact of delaying vaccination against SARS-CoV-2 assuming unlimited vaccine supply

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Marcos Amaku ◽  
Dimas Tadeu Covas ◽  
Francisco Antonio Bezerra Coutinho ◽  
Raymundo Soares Azevedo ◽  
Eduardo Massad
Keyword(s):  
Mathematical Model ◽  
Vaccination Campaign ◽  
Vaccination Rate ◽  
Sao Paulo ◽  
The State ◽  
São Paulo ◽  
Health Authorities ◽  
The World ◽  
The Moment ◽  
The Impact

Abstract Background At the moment we have more than 177 million cases and 3.8 million deaths (as of June 2021) around the world and vaccination represents the only hope to control the pandemic. Imperfections in planning vaccine acquisition and difficulties in implementing distribution among the population, however, have hampered the control of the virus so far. Methods We propose a new mathematical model to estimate the impact of vaccination delay against the 2019 coronavirus disease (COVID-19) on the number of cases and deaths due to the disease in Brazil. We apply the model to Brazil as a whole and to the State of Sao Paulo, the most affected by COVID-19 in Brazil. We simulated the model for the populations of the State of Sao Paulo and Brazil as a whole, varying the scenarios related to vaccine efficacy and compliance from the populations. Results The model projects that, in the absence of vaccination, almost 170 thousand deaths and more than 350 thousand deaths will occur by the end of 2021 for Sao Paulo and Brazil, respectively. If in contrast, Sao Paulo and Brazil had enough vaccine supply and so started a vaccination campaign in January with the maximum vaccination rate, compliance and efficacy, they could have averted more than 112 thousand deaths and 127 thousand deaths, respectively. In addition, for each month of delay the number of deaths increases monotonically in a logarithmic fashion, for both the State of Sao Paulo and Brazil as a whole. Conclusions Our model shows that the current delay in the vaccination schedules that is observed in many countries has serious consequences in terms of mortality by the disease and should serve as an alert to health authorities to speed the process up such that the highest number of people to be immunized is reached in the shortest period of time.

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