Effect Of Different Parameter Values Research Articles

Propagation dynamics of multipole solitons generated in dissipative systems

The propagation dynamics of multipole solitons generated in dissipative systems are investigated numerically based on the fractional complex cubic-quintic Ginzburg–Landau equation using the Airy beam as the input beam. The effect of different parameter values on the generation of stable solitons is explored. In addition, we observe different resultant domains of the input beam evolving in the linear loss coefficient or cubic gain coefficient and Lévy index parameter planes. The results show that the evolution can lead to the formation of stable multipole solitons. It is also demonstrated that two solitons merge to form a single soliton. And, the relation between the merger distance and the initial amplitude is given.

Optimal control in models of virus propagation

Based on the SEIRD model, we consider that when multiple viruses of different virulence coexist, the more virulent virus will reinfect nodes already infected by the less virulent virus, which we call here Superexposed. Based on the state transitions, the corresponding differential equations and cost functions are established, then building the corresponding optimal control problem, where the vaccine efficiency and drug efficiency are controlled variables. This nonlinear optimal control problem is solved by Pontryagin’s maximum principle to finding the structure of the optimal control strategies. Based on the definition of the basic regeneration number, yielding the R0 value for the model, then discussed the final epidemic size. In the numerical analysis section, we validate the accuracy of the structure, fitting the behavior of each state and the effect of different parameter values.

Effect of Different Parameter Values for Pre-processing of Using Mammography Images

Breast cancer is one of the most common types of cancer in women. To make a fast diagnosis, mammography images should have high contrast. Computer-assisted diagnosis (CAD) models are computer systems that help diagnose lesioned areas on medical images. The aim of this study is to examine the contribu-tion of the changes in parameter values of various pre-processing methods used to increase the visibility of mammography images and reduce the noise in the images, to the classification performance. In this study, the mini-MIAS database were used. Gaussian filter, Contrast Limited Adaptive Histogram Equalization and Fast local Laplacian filtering methods were applied as pre-processing method. In this study, two different parameter values were applied for two different image processing methods (Ⅰ. Parameter values are Gauss filter 𝜎=3, Laplacian filter 𝜎=0.6 and 𝛼=0.6; Ⅱ. Parameter values are Gauss filter 𝜎=1, Laplacian filter 𝜎=2 and 𝛼=2). In the normal-abnormal tissue classification, higher accuracy and area under the curve were obtained in the 2nd parameter values in all classification methods. As a result, it has been acquired that different parameter values of the pre-processing methods used to improve mammography images can change the success of the classification methods.

Pavement maintenance and rehabilitation budget allocation considering multiple objectives and multiple stakeholders

ABSTRACT Highways play an important role in economic and social development at both national and regional levels. As a major component of highway infrastructure, pavements require significant funding to be maintained at an acceptable level of service. Allocating the budget for pavement maintenance and rehabilitation (M&R) is a complex decision-making process for a highway agency. This allocation of funding across M&R activities and across districts becomes a challenging process with the presence of multiple stakeholders, constrained budgets, customer satisfaction, agencies' strategic goals, and deteriorating pavement conditions. This paper proposes an extended goal-programming framework for allocating the available pavement M&R budget across multiple management districts of a highway agency over its planning horizon. A case study of applying the proposed model is conducted using data from the Texas Department of Transportation (TxDOT), where five objectives are considered: maximise the proportion of pavement sections with best conditions, minimise the proportion of pavement sections with worst conditions, minimise crash severities through pavement M&R, minimise energy consumption due to M&R activities, and maximise the total lane mile of pavement sections receiving M&R treatments. A sensitivity analysis is also conducted to examine the effect of different parameter values on the results of budget allocation.

Preliminary project design for insect production: part 1 – overall mass and energy/heat balances

Preliminary project design (PPD) is an initial stage in project development that makes it possible for an entopreneur to gain insight into the feasibility and potential profitability of setting up an insect production facility. In this paper a simple, spreadsheet-based model is presented to facilitate the first step of PPD by estimating the overall mass and energy balances for a proposed project. The model calculates outputs on the basis of scientific data and estimated values for operating parameters for the system that is proposed. With the model it is easy to use a trial-and-error approach to investigate the effect of different parameter values on system operation. Thus, the entopreneur can enter values for parameters such as feed composition, temperature of the cooling air, etc. and see the effect on system productivity, conversion efficiency, energy requirements, etc. immediately. This facilitates the overall procedure of reaching final decisions about the organism, the feed, the processing approach, the scale of operation, etc. Normally, this is an iterative procedure that is based on ‘trial-and-error’, the two aspects being referred to here as the ‘twin components of an iterative knowledge engine’. Thus, the outputs from the model will depend very much on the scientific data supplied and the values of the input parameters while, at the same time, use of the model will highlight what additional scientific data is needed and what alternate parameter values might prove profitable. Overall, the model allows the user to explore a large possibility space for both process constitution and operation much more quickly and easily than by experimental means alone. As such, it is a tool that can aid the entopreneur in thinking about a project and considering various alternatives, as well as in making decisions before a major commitment is made to any particular option. It is stressed here that PPD is only a preliminary stage in project development and that the investigation of overall process mass and energy balances is only the first step thereof. It is also stressed that results from modelling are invariably subject to empirical verification as well as ‘common-sense filtering’. The model presented is general and thus not oriented to the production of any species in particular.

Cooperative spectrum prediction algorithm based on overlapping alliance game

In order to solve the problem of unsatisfactory accuracy of spectrum prediction in a network with multiple primary users, this paper proposes a cooperative spectrum prediction algorithm. The overlapping alliance game is introduced into spectrum prediction. The alliance structure with the highest accuracy of collaborative prediction is selected, and the result with the highest accuracy is obtained. In the experiment, three different collaborative prediction methods are compared and the effects of different parameter values on the simulation results are analysed. The results show that the proposed method has high prediction accuracy, adaptability and robustness.

Cooperative spectrum prediction algorithm based on overlapping alliance game

In order to solve the problem of unsatisfactory accuracy of spectrum prediction in a network with multiple primary users, this paper proposes a cooperative spectrum prediction algorithm. The overlapping alliance game is introduced into spectrum prediction. The alliance structure with the highest accuracy of collaborative prediction is selected, and the result with the highest accuracy is obtained. In the experiment, three different collaborative prediction methods are compared and the effects of different parameter values on the simulation results are analysed. The results show that the proposed method has high prediction accuracy, adaptability and robustness.

The Stability and Complexity Analysis of a Low-Carbon Supply Chain Considering Fairness Concern Behavior and Sales Service.

This paper studies a low-carbon dual-channel supply chain in which a manufacturer sells products through the direct channel and traditional channel, and a retailer sells products through the traditional channel. The manufacturer considers carbon emission reduction and has fairness concern behavior. The retailer provides sales service in the traditional channel and considers fairness concern behavior. The objective of this paper is to analyze the effects of different parameter values on the price stability and utility of the supply chain system emphatically using 2D bifurcation diagram, parameter plot basin, the basins of attraction, chaos attractor and sensitivity to the initial value, etc. The results find that the retailer’s fairness concern behavior shrinks the stability of the supply chain system more than that of the manufacturer’s fairness concern behavior. The system stability region decreases with the increase of carbon emission reduction level and the retailer’s fairness concern. The customers’ preference for the direct channel decreases the stable range of the direct channel, while it enlarges the stable range of the traditional channel. The supply chain system enters into chaos through flip bifurcation with the increase of price adjustment speed. In a stable state, the manufacture improving customer’s preference for the direct channel and the retailer choosing the appropriate fairness concern level can achieve the maximum utility separately. In a chaotic state, the average utilities of the manufacturer and retailer all decline, while that of the retailer declines even more. By selecting appropriate control parameter, the low-carbon dual-channel supply chain system can return to a stable state from chaos again. The research of this paper is of great significance to price decisions of participants and supply chain operation management.

A Dynamic Price Game Model in a Low-Carbon, Closed-Loop Supply Chain Considering Return Rates and Fairness Concern Behaviors.

In this paper, we developed a dynamic price game model for a low-carbon, closed-loop supply chain system in which (1) the manufacturer had fairness concern and carbon emission reduction (CER) behaviors, and market share and profit maximization were their objectives, and (2) the retailer showed fairness concern behaviors in market competition and provided service input to reduce return rates. The retailer recycled old products from customers, and the manufacturer remanufactured the recycled old products. The effects of different parameter values on the stability and utility of the dynamic price game model were determined through analysis and numerical simulation. Results found that an increasing customer loyalty to the direct marketing channel decreased the stable region of the manufacturer’s price adjustment and increase that of the retailer. The stable region of the system shrank with an increase of CER and the retailer’s service level, which expanded with return rates. The dynamic system entered into chaos through flip bifurcation with the increase of price adjustment speed. In the chaotic state, the average utilities of the manufacturer and retailer all declined, while that of the retailer declined even more. Changes to parameter values had a great impact on the utilities of the manufacturer and retailer. By selecting appropriate control parameters, the dynamic system can return to a stable state from chaos again. The research of this paper is of great significance to participants’ price decision-making and supply chain operation management.

Models to assess the effects of non-identical sex ratio augmentations of Wolbachia-carrying mosquitoes on the control of dengue disease

The introduction of endosymbiont Wolbachia into laboratory-reared mosquito populations, which are then released to mix with natural populations to prevent the mosquito vectors from reproducing and thus break the transmission cycle of dengue disease, is an innovative new technology. Field trials of Wolbachia-carrying mosquitoes have now been implemented in many countries where there have been the outbreaks of dengue disease. A mathematical model is proposed to investigate the effects of non-identical sex ratio releases of Wolbachia-carrying mosquitoes on the control of dengue transmission. Firstly, we analyzed the existence and stability of equilibria for the system and proved the existence of forward and backward bifurcations. Secondly, bifurcation diagrams, the basins of attraction of the equilibria and the effects of mosquito augmentation for the system with imperfect and perfect transmission rates were obtained. Thirdly, three possible results for mosquito augmentation were summarized for different parameter regions. Further we explored an uncertainty and sensitivity analysis of solutions to estimate the effects of different parameter values on the success or failure of population replacement. Based on the above analysis, we considered a series of relevant issues such as (a) whether or not mosquito augmentation can ensure the success of population replacement? (b) If not, what are the parameter regions for the success or possible success of population replacement? (c) How does the initial density of natural mosquitoes and the quantity of mosquito augmentations affect the success of population replacement? (d) Whether all population replacements are effective for reducing the spread of dengue virus in the end? The results of this study will be helpful for public health authorities in designing proper strategies of mosquito augmentations for the control of dengue disease.

Static and Dynamic Performance Simulation of Direct-Acting Force Motor Valve

This work focuses on static and dynamic characteristics of direct-acting force motor valve. First, we analyzed the structure features and operating principle of the Mitsubishi-Hitachi force motor valve (FMV) and the operating principle of its internal permanent-magnet moving-coil force motor magnetic circuit, determined the transfer function of the FMV force motor system, and established a mathematical model for the system. Secondly, we established a static performance analysis model using the AMESIM software and utilized the model in combination with experimental results to analyze the effects of electro-hydraulic servo valve structural parameters on static characteristics. Lastly, we deduced the trajectory equation of the system, established the relationship between dynamic characteristic indexes and structural parameters, and analyzed the effects of different parameter values on the dynamic characteristics of the system. This research can provide a theoretical guidance for designing and manufacturing the FMV body.

Mathematically modelling the spread of hepatitis C in injecting drug users

Mathematical modelling can provide valuable insights into the biological and epidemiological properties of infectious diseases as well as the potential impact of intervention strategies employed by health organizations worldwide. In this paper, we develop a deterministic, compartmental mathematical model to approximate the spread of the hepatitis C virus (HCV) in an injecting drug user (IDU) population. Using analytical techniques, we find that the model behaviour is determined by the basic reproductive number R(0), where R(0) = 1 is a critical threshold separating two different outcomes. If R(0) ≤ 1 and HCV is initially present in the population, we find that the system will reach a disease-free equilibrium where HCV has been eliminated in all IDUs and needles. If R(0) > 1, then there is a unique positive endemic equilibrium which we show is locally stable. We then use simulations to verify our analytical results and examine the effect of different parameter values and intervention measures on HCV prevalence estimates.

Influence of oxygen/argon pressure ratio on the morphology, optical and electrical properties of ITO thin films deposited at room temperature

Transparent conductive oxides (TCOs) such as indium tin oxide (ITO) thin films onto glass substrates are widely used as transparent and conductive electrodes for a variety of technological applications including flat panel displays, solar cells, smart windows, touch screens, etc. ITO films on glass and polycarbonate (PC) substrates were prepared at room temperature (RT) and at different P O 2 . The films were characterized in terms of the surface roughness ( δ), sheet resistance, the refractive index ( n) and extinction coefficient ( k). The free carrier density ( n c) and the carrier mobility ( μ) of the ITO (In 2O 3:Sn) films were measured and studied. The n c and μ values vary in different ratio of oxygen partial pressure ( P O 2 ) of ITO deposition. The observed changes in the ITO film resistivity are due to the combined effect of different parameter values for n c and μ. From AFM analysis and spectra calculations, the surface roughness values of the ITO films were studied and it was observed that the δ values were lower than 15 nm. The energy band gap E g ranges from 3.26 eV to 3.66 eV as determined from the absorption spectrum. It was observed an increase on the energy band gap as the P O 2 decrease in the range of 20–2% P O 2 . The Lorentz oscillator classical model has also been used to fit the ellipsometric spectra in order to obtain both refractive index n and extinction coefficient κ values.

Nonthermal Compton and Synchrotron Processes in the Jets of Active Galactic Nuclei

We present the basic equations for calculating the time-dependent received spectral flux from the optically thin emissivities produced by temporally evolving, nonthermal electrons losing energy in a relativistically moving blob of plasma located at cosmological distances. Ionization, bremsstrahlung, Compton, and synchrotron energy losses of the electrons are considered. These equations are used to derive and calculate the received spectral fluence produced by instantaneously injected nonthermal electrons that also scatter photons from an isotropic external monochromatic radiation field in the Thomson regime of scattering. The derivation of the fluences is restricted to the regime where either synchrotron losses or Thomson losses with photons of the external radiation field dominate the electron energy loss rate. We also derive approximate expressions for the synchrotron and synchrotron self-Compton fluence. Beaming factors for thin-target and thick-target models of the electron distributions are derived. We show that ionization energy losses of relativistic electrons on the background thermal plasma of the blob can give Comptonized gamma-ray fluence spectra with spectral breaks Δα 0.5. If only Thomson and synchrotron losses are important, spectral breaks 0.5 are also possible if electrons are injected with a low-energy cutoff or if a snapshot of the spectral flux is measured over a time interval much less than the interval during which electrons cool. The important observational quantities for testing Compton-scattering models of radio galaxies and blazars are the bolometric luminosities in the radio/optical synchrotron component and the X-ray/γ-ray Compton component, which approximately equal the peak values of the νFν spectral power flux or fluence. Numerical simulations of jet spectra are presented, showing the effects of different parameter values on the shapes of the synchrotron and Compton components. We derive straightforward predictions for the simplest external Compton and synchrotron self-Compton models from the analytic expressions for the spectra. The results are applied to quasi-simultaneous observations of 3C 279 at two different epochs, showing that this behavior can be understood if the blazar radiation results from electrons that Compton-scatter externally produced photons in outflowing blobs with different bulk Lorentz factors. Fits to quasi-simultaneous observations of 3C 273 and quiescent and flaring states of Mrk 421 are also presented.

Optmizing Radiologic Costs in the DRG Environment

Previously developed consensus algorithms expressing a suggested radiologic workup for the diagnostic related groups (DRGs) specified by the prospective reimbursement policy have proven to be useful tools for investigating radiologic decision making and the resulting economic implications. The mathematical equations for determining diagnostic and therapeutic costs for two alternative algorithms for suspected acute cholecystitis are formulated. Illustrative examples and graphic displays are given regarding how such algorithms and equations are useful in finding answers to questions about the appropriate diagnostic workup, time, and cost. Exploration of the effect of different parameter values on the choice of the appropriate algorithm is illustrated.

A catastrophe theory description of stick-slip motion in sliding

Stick-slip motion is analyzed by studying structural changes in the mathematical model describing sliding friction. The sliding system is assumed to operate in a way which minimizes energy input to the system. For an exponential dependence of friction force on sliding velocity, the system sliding behavior is multivalued for some ranges of values of the system parameters. The effect of different parameter values on system behavior is illustrated and results of this investigation are compared with a published steady sliding criterion.