As the main source of government revenue, the tax has always faced numerous challenges on the taxpayers’,part, such as tax evasion, late tax payment, and falsification of tax records. The problems with the Calculation of taxable income cause these challenges. Therefore, a change in the Calculation basis seems to serve as a solution to these challenges. This study aims to develop an optimal model for tax Calculation, where the confirmable income act as the basis for tax Calculation. Taxable income results from the subtraction of confirmable revenues and costs from extra-organizational financial resources. The study population consists of financial information of firms listed on the Tehran Stock Exchange from 1997 to 2016. Initially, instead of the taxable income, confirmable income is introduced as an optimal model,afterward, for the sake of accuracy, the tax rates for every firm and year are re-calculated using median, mean, regression, and artificial bee colony algorithm. Then the calculated taxes and real taxes were compared using paired t-tests. Finally, the rate that showed the slightest difference with the real rates, at the confidence level of 95%, is selected as the rate of the Industry/Firm-Year Group. The results show that this new method entails the use of the industry/firm group special rate every year,in other words, the tax rate of each group changes according to the inflation rate and economic conditions. This new method can also assist the government to gain more benefits from tax resources.

All oscillators are periodically time varying systems, so to accurate phase noise Calculation and simulation, time varying model should be considered. Phase noise is an important characteristic of oscillator design. It defined as the spectral density of the oscillator spectrum at an offset from the center frequency of the oscillator relative to the power of the oscillator. In this paper, we study linear time invariant (LTI) and linear time variant (LTV) model’s to calculate phase noise. Moreover, we propose a simple method for Impulse Sensitivity Function (ISF) Calculation. Different oscillators have been selected to evaluate the proposed method. Simulation results show that the proposed method is simpler than other methods, and we can easily simulation ISF.

Purpose: This study aims to advance the existing analytic model to include staff allocation information at thedistrict level. Maintaining adequate size of staff is essential to law enforcement agencies’,ability to ensure socialorder, fight crime and, increasingly, deliver a widening range of social services. Review of the scientificliterature on police size of force and staffing Calculation models indicates that this line of inquiry (i. e. manpoweranalysis) is attentive to population size and workload demands but generally inattentive to how servicedemands are affected by community-level variables. Current staffing Calculation models specify number ofstaff needed for a jurisdiction but do not inform the allocation of personnel across districts within thejurisdiction. Design/methodology/approach: To address this problem, the current study illustrates an enhancedanalytic model to provide law enforcement staffing recommendations for a southern coastal county. Anintegrated per capita-workload manpower analysis model first factors the minimum number of lawenforcement deputies needed per population size served and recent history workload demands and thenexecutes the six-step workload model process. This study enhances staffing analysis by adding an additionalseventh arithmetical step indicating the staffing needs by districts across a jurisdiction. Findings –,The results from the integrated per capita-workload analysis indicate the need to hire additionaldeputies to meet current and future demands. Originality/value –,Discussion: centers on the need to include drivers of police services identified but notmeasured in this study’, s application of the hybrid manpower analysis model and its replication potential. Keywords Manpower analysis, Strength of force, Law enforcement staffing.

Although two-phase flow is frequently encountered in various locations of the process plants, there is no a generally accepted and verified twophase flow model that may be used to size lines for such conditions. An obvious example is condensate water return lines. The API method used in this study is based on the homogeneous equilibrium flow assumption, that is, equal velocity and equal temperature in both liquid and vapor phases. Moreover, DIERS method was used to verify and clarify the HEM approach to calculating the pressure drop in twophase regimes. The objective of this study is to introduce a solution for process lines design during different flashing scenarios. Applying API method, this study can find the two-phase line pressure drop and upstream pressure, while, by using DIERS method, one could realize that for a specified length of pipe how much two-phase flow could pass through when the pressure drop is just the same as that in the API model.

One of the most important issues that is currently considered in most researches is the discussion of avoidance and its influencing factors and the results. Theoretically, tax avoidance is an attempt to reduce tax payments, so many companies appear to be involved in tax avoidance, so determining the factors that influence the level of tax avoidance in companies is important so far as a comprehensive indicator for it is not provided. Therefore, this study presents a comprehensive index for assessing tax avoidance by considering different indices using mathematical method. Also for testing and evaluation of the designed model, data from 152 companies during 2012-2019 were used in mixed method. For this purpose, a questionnaire was prepared and distributed among the experts about the weight and importance of the criteria considered for measuring corporate tax avoidance and the weight and importance of criteria were determined using one of the methods of multi-criteria decision making model (Shannon entropy). Confirmatory factor analysis was also used to measure the hidden variable relationships in this tax avoidance study,the results show that the proposed model is a good indicator for tax avoidance.

Space headway Calculation and analysis play an important role in identifying surrounding obstacles and understanding traffic scenes. However, the performance of existing methods is limited by the complexity of computer processing. In addition, it is quite difficult to obtain space headway at turn movement trajectories, mainly owing to the limitation of rectilinear propagation. Therefore, a hybrid model based on spline curve and numerical integration was proposed to estimate the distance of the front vehicle and vehicle trajectory in this study. The space headway at turn movement trajectories was analogous to the track of a vehicle, which could be  fitted by a quadratic spline curve. Newton-Cotes numerical integration was employed to calculate distance due to its meshing flexibility and ease of implementation. Data collected from Lankershim Boulevard in the city of Los Angeles, California (USA) were used to evaluate performance of the hybrid model. Compared with another algorithm based on computer vision and trilinear method, the results showed that the proposed model worked successfully and outperformed the competing method in terms of accuracy and reliability. Finally, the proposed method was applied to investigate the effects of vehicle speed, relative speed of vehicles, and time period on the spacing of vehicles during car-following.

This paper presents molecular dynamics modeling for calculating viscosity of nanofluids containing copper nanoparticles. In the first case, the copper nanoparticles were located as a spherical region in water-based fluid module SPC. System under specified boundary conditions, and writing code by LAMMPS software, and nanofluid ratios of 3.2, 4.4, 6.9 and 9.1 percented by Brownian motion of atoms, was carried out. three popular potential function, Lennard-Jones, Coulomb, and embedded atom method were used. Between equilibrium molecule dynamic, and non- equilibrium molecule dynamic, (EMD) and Green-kubo formula were used to calculate viscosity. The results show that by increasing the amount of voloume fraction, viscosity increases. nanofluids in addition to other factors, such as volume fraction of particles in Brownian motion and clustering phenomenon, each in turn causes changes in viscosity. The simulation results were compared with other's works and found that the obtained results are remarkably accurate.