Journal articles on the topic 'Automobile ownership Mathematical models'
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1
Chu, You-Lian. "Automobile Ownership Analysis Using Ordered Probit Models." Transportation Research Record: Journal of the Transportation Research Board 1805, no. 1 (January 2002): 60–67. http://dx.doi.org/10.3141/1805-08.
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Goetzke, Frank, and Rachel Weinberger. "Separating Contextual from Endogenous Effects in Automobile Ownership Models." Environment and Planning A: Economy and Space 44, no. 5 (May 2012): 1032–46. http://dx.doi.org/10.1068/a4490.
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Kumar, Naresh, and Balraj Singh. "Forecast of Indian Automobile Industry Using Mathematical Models." Paradigm 7, no. 2 (July 2003): 105–16. http://dx.doi.org/10.1177/0971890720030207.
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Lee, Seunghoon, Young Hoon Lee, and Yongho Choi. "Project Portfolio Selection Considering Total Cost of Ownership in the Automobile Industry." Sustainability 11, no. 17 (August 23, 2019): 4586. http://dx.doi.org/10.3390/su11174586.
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Project portfolio selection for developing a new product is critical to a company because the attributes of the project reflect on the price, quality, and functionality of the developed product. The market evaluates the developed product and the assessment of the product value determines its sale on the market. The project portfolio selection and sales are interconnected from a corporate perspective. The automobile industry is an industry which responds to the issue of business sustainability sensitively because their business directly relates to the environment. In this study, business sustainability was approached through the perspective of total cost of ownership (TCO) embedded into the project selection model after the attributes of the project, investment and efficiency, and the TCO of the product were combined to generate a sales function. The sales and revenue models were proposed, and the validity of the models was confirmed using a case from the automobile industry. As a result of the experiments, the sales model tended to show that the market share increased by selecting the proper number of projects to maximize sales. In contrast, the revenue model showed a tendency to select projects more than the sales model in order to maximize the profits of the company. By suggesting project selection models in a new perspective different from the ones in existing studies, this study is valuable with regard to the fact that the suggested models preserve project interrelationships, TCO, and product sales in a practical manner to enhance business sustainability.
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Toney, Glenson, and Cherry Bhargava. "Adaptive Headlamps in Automobile: A Review on the Models, Detection Techniques, and Mathematical Models." IEEE Access 9 (2021): 87462–74. http://dx.doi.org/10.1109/access.2021.3088036.
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Mohammadian, Abolfazl, and Eric J. Miller. "Empirical Investigation of Household Vehicle Type Choice Decisions." Transportation Research Record: Journal of the Transportation Research Board 1854, no. 1 (January 2003): 99–106. http://dx.doi.org/10.3141/1854-11.
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Automobile ownership models are an integral part of comprehensive transportation modeling systems. Recent work and ongoing advances in the area of activity-based travel demand modeling have recognized the need for increased experimentation with automobile choice models. On the other hand, while automobiles are very important in people's everyday lives, they also have a serious impact on the environment. This impact occurs at the micro level (pollution) as well as the macro level (emission of greenhouse gases and global warming). Such impacts have led to increased interest in reducing motor vehicle emissions. A household automobile type choice model was developed at a disaggregate level. The model can provide a direct forecast of consumer demand for personal-use vehicles given the available choices. A well-developed form of discrete choice modeling techniques, the nested logit model, was used to investigate the process of household automobile type choice decisions given that a transaction has occurred.
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Kumbár, Vojtěch, Josef Glos, and Jiří Votava. "Monitoring of Chemical Elements During Lifetime of Engine Oil." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 62, no. 1 (2014): 155–59. http://dx.doi.org/10.11118/actaun201462010155.
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Awareness of engine oil condition is a valuable indicator for assessing the state of degradation of the lubricant. The article deals with monitoring of chemical elements, especially metals and additives, during lifetime of commercially distributed automobile engine oil Castrol Magnatec 10W–40. Engine oil was regarded as a Newtonian fluid. The passenger car Renault Scenic I with petrol engine (four pistons, volume 1,600 cm3) was used to the observed. Lifetime of automobile engine oil has been stated by car and lubricants producers in interval 15,000 km. The samples of automobile engine oil have been taken in suitable intervals – 1,500 km. Only first sample of used engine oil was taken with raid 20 km. The seasons of monitoring were spring and summer. The spectrometer Spectroil Q100 has been used to monitoring of chemical elements in automobile engine oil. Increase contents of metals and decrease contents of additives were observed. The results were modelled using mathematical models with given the values of coefficient correlation R. Linear function as a mathematical model with the lowest number of degrees of freedom was used. Created mathematical models can be used to predict of conditions of engine oil in the same or similar petrol engine aggregates.
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Katanaev, N. T., A. V. Lepeshkin, and A. F. Kolbasov. "Identification of the longitudinal movement of the vehicle in free-wheel mode." Izvestiya MGTU MAMI 9, no. 4-1 (February 20, 2015): 103–9. http://dx.doi.org/10.17816/2074-0530-67238.
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The results of the simulation of automobile rectilinear motion are provided in the paper. An overview of some of the existing models was made. The analysis was performed in order to obtain analytical information about the balance of effective forces and resistance forces of an object in free-wheel mode. The reliable mathematical description is needed to develop models of human- machine system “automobile - environment - driver” and to study the influence of various fac- tors on the performance of control object.
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Feng, Jia, Meng Meng, Shanshan Liu, Xin Zhang, Jie Yuan, and Zengyong Zhang. "Prediction of Chinese Automobile Growing Trend Considering Vehicle Adaptability based on Cui–Lawson Model." Applied Mathematics and Nonlinear Sciences 5, no. 2 (November 16, 2020): 367–76. http://dx.doi.org/10.2478/amns.2020.2.00054.
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AbstractThe rapid growth of fossil fuels and the aggravation of emission pollution can be improved by the green and diversified energy structure of road transport vehicles. In this article, Cui–Lawson model is first introduced to analyse the change trend of pure electric vehicle, hybrid electric vehicle, gas–fuel vehicle, fuel cell vehicle, biofuel vehicle and traditional vehicle in the next 50 years. Considering the climate, environment and economic development of each region, the future ownership of the above six models was studied by region. Moreover, the climate and topography affect the developing trend strongly. The ownership of traditional automobile is more than other kinds of vehicles until 35 and 40 years in Xibei and Dongbei regions for the cold temperature.
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Dyakov, Ivan, and Olegas Prentkovskis. "OPTIMIZATION PROBLEMS IN DESIGNING AUTOMOBILES." TRANSPORT 23, no. 4 (December 31, 2008): 316–22. http://dx.doi.org/10.3846/1648-4142.2008.23.316-322.
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A mathematical model of optimization problems in designing automobiles is suggested and requirements raised are defined taking into account the main technical and economic characteristics of the automobile. The optimality criterion of the integral parts of the automobile is presented. The system approach to the theory of parametric optimization based on generalized models is used and the algorithm for solving the considered problem is offered.
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Bogdevicius, Marijonas, Jolanta Janutėnienė, and Oleg Vladimirov. "Simulation of Hydrodynamics Processes of Hydraulic Braking System of Vehicle." Solid State Phenomena 147-149 (January 2009): 296–301. http://dx.doi.org/10.4028/www.scientific.net/ssp.147-149.296.
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The 3D vehicle with the hydraulic braking system and disc brake with the wheel has been investigated. The dynamic models of the disk brake assembly and the wheel have been constructed. The automobile hydraulic braking system consisting of two contours is considered. . The mathematical model of the hydraulic braking system is presented, where the flow of liquid and the interaction of liquid with the rigid bodies are taken into account. The flow of fluid in a hydraulic system is described by a system of equations of a hyperbolic type, which is solved by a characteristics method. During the mathematical simulations and natural experimentations the following results were achieved. The systems of equations of dynamic models’ motions are solved by numerical methods. The dynamic characteristics of the braking system of the automobile are obtained. The results of extreme braking tests and calculations are presented.
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Chen, Hung-Yuan, Yu-Ming Chang, and Hua-Cheng Chang. "A numerical definition-based systematic design approach for coupling consumers ' image perception with product form." Journal of Engineering, Design and Technology 14, no. 1 (March 7, 2016): 134–59. http://dx.doi.org/10.1108/jedt-11-2013-0075.
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Purpose – This paper aims to propose a numerical definition-based systematic design approach (NDSDA) to generate an explicit numerical definition of the product form profile and to establish the correlation between the product form features and the corresponding consumers’ image perceptions. Design/methodology/approach – To illustrate the feasibility of the proposed method, this study considers the design of a two-dimensional automobile profile for illustration purposes and commences by developing a detailed numerical definition of an automobile profile using Bézier curves. A series of automobile image evaluations are conducted to examine the relationship between the characteristics of an automobile profile and its associated consumer image perception. Finally, the evaluation results are analyzed statistically, and the statistical results are used to construct mathematical models formalizing the correlations between the automobile profile design variables and the consumers’ perceptions of the product image. Findings – The results of the evaluation trials are used to construct mathematical models capable of predicting the likely consumer response to any automobile profile designed in accordance with the numerical definition. Furthermore, the evaluation data enable the critical design variables and form features to be determined such that the efficacy of the design process in creating automobiles which better meet the consumers’ image aspirations can be improved. Originality/value – The major contribution of the NDSDA methodology presented in this study is the ability it gives to designers to specify the product form in a detailed yet highly efficient manner. Furthermore, the numerical definition of the product form not only provides a suitable basis for identifying the critical design variables and form features of the product but also provides an understanding of how these variables should be manipulated to obtain or reinforce the desired product image.
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Shodiev, J., and M. Azimov. "Mathematical modeling of truck movement in rough road conditions of agricultural area." IOP Conference Series: Earth and Environmental Science 1076, no. 1 (August 1, 2022): 012003. http://dx.doi.org/10.1088/1755-1315/1076/1/012003.
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Abstract The article presents the methods of modeling the horizontal and vertical movement of a small truck Labo. Using the Lagrange equation of the second type, mathematical models of the movement of a small truck Labo on uneven roads developed. The mathematical models developed by the Runge-Kutta-number method solved and the values of the horizontal and vertical oscillations, speeds of movement and the forces acting and acting on each wheel of the automobile found. On the given masses, the parameters of the automobile’s leaf springs and the depreciation part are determined.
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Manouchehrynia, Reza, Shahrum Abdullah, and Salvinder Singh Karam Singh. "Fatigue Reliability Assessment of an Automobile Coil Spring under Random Strain Loads Using Probabilistic Technique." Metals 10, no. 1 (December 20, 2019): 12. http://dx.doi.org/10.3390/met10010012.
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This paper presents a mathematical model to estimate strain-life probabilistic modeling based on the fatigue reliability prediction of an automobile coil spring under random strain loads. The proposed technique was determined using a probabilistic method of the Gumbel distribution for strain-life models of automobile suspension systems. Strain signals from different road excitations in experimental tests were measured. The probability density function of the Gumbel distribution was considered to estimate model parameters using maximum likelihood estimation (MLE). The Akaike information criterion (AIC) method was performed to specify which model can estimate the best fit model parameters. Results demonstrated a good agreement between the predicted fatigue lives of the proposed probabilistic model and the measured strain fatigue life models. The root-mean-square errors (RMSE) based on the Coffin–Manson, Morrow, and Smith–Watson–Topper strain-life models were approximately 0.00114, 0.00107, and 0.00509, respectively, indicating a high correlation with the proposed model and experimental data. The results demonstrated that the proposed probabilistic model is effective for the fatigue life prediction of automobile coil springs using strain and stress fatigue life approaches.
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Sousa, M. Luísa, and Rafael Marques. "Political Transitions, Value Change and Motorisation in 1970s Portugal." Journal of Transport History 34, no. 1 (June 2013): 1–21. http://dx.doi.org/10.7227/tjth.34.1.2.
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During the revolutionary period of 1974–76, there was vigorous debate in Portugal regarding the role of automobiles in the desired new society. The dispute was reinforced by the first international oil crisis. Strong ideological rhetoric was deployed either to defend the potentially liberating role of the automobile or to condemn its ‘bourgeois' underpinnings. This debate influenced social movements, policies, perceptions and views of social actors, thus contributing to market distortions, a short-lived disappearance of luxury and sports cars and to the creation of new models deemed to be adapted to the ‘true’ needs of the Portuguese. It also contributed to changes in automobile assemblage industry, road policy and delays in the implementation of road safety measures. Environmental, safety and traffic concerns were subdued, for a while, by a more essentialist approach to car consumption, with opposing interests trying to define the social spirit of automobile ownership and usage. The political turmoil of the period and the lack of coherent and durable policies account for the period being an intermission and not the beginning of a new trend.
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Gorbatovskiy, A. V., G. O. Kotiev, and A. O. Chulyukin. "Electromechanical system for providing continuity summing power to the driving machine when shifting gears in transmission of a vehicle." Izvestiya MGTU MAMI 9, no. 3-1 (February 10, 2015): 8–16. http://dx.doi.org/10.17816/2074-0530-67163.
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The paper provides description of mathematical models of the transmission with an electrome- chanical system for providing continuity summing power to the engine when shifting gears, and the traditional transmission, which allow studying automobile acceleration characteristics. The resultsof computer modeling of process of a gear shift for the considered designs are shown.
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Xiao, Ping, Li Tian, and Hong Gao. "Digitalized Design of Upward-and-Downward Adjusting Mechanism of Automobile Seat." Applied Mechanics and Materials 275-277 (January 2013): 2471–76. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.2471.
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Abstract. Worm-cam combined mechanism was chosen as the kinematic precept of upward-and-downward adjusting mechanism of automobile seat on the basis of functional requirements. The designing mathematical model of the combined mechanism was built on the basis of mechanism theories, and its programs were written in Matlab to solve the model. Parameterized models of every parts of the combined mechanism were built and their virtual assembly was carried out in CATIA. In ANASYS, which was based on assembly finite element analysis, the strength and rigidity of the combined mechanism assembly digital models was analyzed and evaluated. Finally, a design sample was presented.
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Loo, Becky P. Y. "Tunnel Traffic and Toll Elasticities in Hong Kong: Some Recent Evidence for International Comparisons." Environment and Planning A: Economy and Space 35, no. 2 (February 2003): 249–76. http://dx.doi.org/10.1068/a3590.
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In this paper, a set of double-log multiple regression models is developed to examine the monthly tunnel traffic of six major toll tunnels in Hong Kong for a 22-year period from January 1979 to September 2000. Despite the much lower percentage of households with cars (12.3%) and the higher dependence of passenger trips on public transport (80.2%), the estimated automobile elasticities in Hong Kong are remarkably similar to those reported in New York, where car ownership is high and the automobile is the dominant mode of transport. The empirical elasticity range in Hong Kong is from —0.103 to —0.291. This is similar to estimates for the United States (—0.13 to —0.45), the United Kingdom (—0.14 to —0.36), and Australia (—0.09 to —0.52). The findings suggest that toll increases are likely to be effective in raising revenue for tunnel management authorities but ineffective in reducing or reallocating automobile traffic for transport planning purposes. Policywise, suburbanization or the redistribution of population could have a much stronger influence on the urban transport market than a ‘multifaceted pricing’ strategy of raising the total costs of vehicle ownership and usage (including high vehicle-registration fees, parking, and gasoline prices). Moreover, improvements to railway connectivity and enhancement of travel speed on public transit could be much more effective than toll increases in relieving urban transport congestion problems at critical bottlenecks, such as downtown and suburb–downtown tunnels and bridges. The inclusion of lagged effects into the analysis further strengthens the above policy recommendations.
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Kulagin, V. A. "Development of a complex of mathematical models of a vehicle suspension for fatigue life analysis." Izvestiya MGTU MAMI 15, no. 4 (December 15, 2021): 33–42. http://dx.doi.org/10.31992/2074-0530-2021-50-4-33-42.
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The reduction in the duration of the development of new vehicles and the associated desire to reduce the costs of automotive plants contribute to a more active application of mathematical modeling to solve engineering problems. The tasks, which are analyzing and predicting the fatigue life of vehicle components and assemblies, can be solved using a set of methods and tools of mathematical modeling.
This article discusses the development of a complex of mathematical models of the front and rear suspensions of a passenger automobile, which have the properties necessary for accurate reproduction of wheel loads and dynamic behavior of the suspension as a mechanical system. The complex of mathematical models is implemented in a multi-link modeling environment. The models are designed to carry out a subsequent validation study of the loading of individual suspension components during forced service life tests. In the future, this complex of mathematical models can be used for simulation of semi-natural forced resource tests of the suspension module, as well as a sample for the development of suspension models of other automobiles.
The purpose of this work is to form sufficient requirements for mathematical models for the implementation of fatigue durability studies using mathematical modeling methods and obtaining reliable calculation results. Research engineers will be able to follow these requirements to determine and collect initial data for the development of their own mathematical models.
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Kornbluth, J. S. H., and G. R. Salkin. "Mathematical programming models for ownership and control of European and American groups of companies." European Journal of Operational Research 74, no. 3 (May 1994): 479–94. http://dx.doi.org/10.1016/0377-2217(94)90225-9.
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Katanaev, N. T., A. V. Lepeshkin, and A. F. Kolbasov. "Simulation of engine speed performance characteristics." Izvestiya MGTU MAMI 10, no. 1 (March 15, 2016): 28–30. http://dx.doi.org/10.17816/2074-0530-66920.
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The paper gives an overview of mathematical descriptions of engine speed performance characteristics that are needed when simulation of “engine-automobile-driver-environment” systems. The analysis of models based on different classes of functions is given; its advantages and disadvantages are discussed. The regression model based on the use of functions closely related to the physics of investigated processes is proposed.
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Zeng, Y., A. Pardasani ,, J. Dickinson ,, Z. Li ,, H. Antunes , and, V. Gupta, and D. Baulier. "Mathematical Foundation for Modeling Conceptual Design Sketches1." Journal of Computing and Information Science in Engineering 4, no. 2 (May 28, 2004): 150–59. http://dx.doi.org/10.1115/1.1683825.
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This paper aims to establish a mathematical foundation for modeling free-hand design sketches throughout the conceptual design process. Both experimental and theoretical approaches are used. In using the experimental approach, one case study from a book and one case study from an automobile assembly system manufacturer are used to illustrate the characteristics of design sketches. These characteristics provide the requirements for models of sketch representation. In using the theoretical approach, a mathematical structure of design sketches is established. This mathematical structure can naturally and logically model the evolving sketches generated in the design process, through integrating the strengths of set theory and mereology. In addition to the formal representation of design sketches, the mathematical model provides a logical foundation for formally designing sketch interpretation algorithms. An algorithmic structure of three-dimension reconstruction from two-dimension line drawing is derived using this mathematical model.
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Ma, Te, Mahdi Aghaabbasi, Mujahid Ali, Rosilawati Zainol, Amin Jan, Abdeliazim Mustafa Mohamed, and Abdullah Mohamed. "Nonlinear Relationships between Vehicle Ownership and Household Travel Characteristics and Built Environment Attributes in the US Using the XGBT Algorithm." Sustainability 14, no. 6 (March 14, 2022): 3395. http://dx.doi.org/10.3390/su14063395.
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In the United States, several studies have looked at the association between automobile ownership and sociodemographic factors and built environment qualities, but few have looked at household travel characteristics. Their interactions and nonlinear linkages are frequently overlooked in existing studies. Utilizing the 2017 US National Household Travel Survey, the authors employed an extreme gradient boosting tree model to evaluate the nonlinear and interaction impacts of household travel characteristics and built environment factors on vehicle ownership in three states of the United States (California, Missouri, and Kansas) that are different in population size. To develop these models, three main XGBT parameters, including the number of trees, maximal depth, and minimum rows, were optimized using a grid search technique. In California, the predictability of vehicle ownership was driven by household travel characteristics (cumulative importance: 0.62). Predictions for vehicle ownership in Missouri and Kansas were dominantly influenced by sociodemographic factors (cumulative importance: 0.53 and 0.55, respectively). In all states, the authors found that the number of drivers in a household plays a vital role in the vehicle ownership decisions of households. Regarding the built environment attributes, deficiencies in cycling infrastructure were the most prominent attribute in predicting household vehicle ownership in California. This variable, however, has threshold connections with vehicle ownership, but the magnitude of these relationships is small. The outcomes imply that improving the condition of cycling infrastructure will help reduce the number of vehicles. In addition, incentives that encourage the households’ drivers not to buy new vehicles are helpful. The outcomes of this study might aid policymakers in developing policies that encourage sustainable vehicle ownership in the United States.
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Maria Kockelman, Kara. "Travel Behavior as Function of Accessibility, Land Use Mixing, and Land Use Balance: Evidence from San Francisco Bay Area." Transportation Research Record: Journal of the Transportation Research Board 1607, no. 1 (January 1997): 116–25. http://dx.doi.org/10.3141/1607-16.
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The relative significance and influence of a variety of measures of urban form on household vehicle kilometers traveled, automobile ownership, and mode choice were investigated. The travel data came from the 1990 San Francisco Bay Area travel surveys, and the land use data were largely constructed from hectare-level descriptions provided by the Association of Bay Area Governments. After demographic characteristics were controlled for, the measures of accessibility, land use mixing, and land use balance—computed for trip-makers’ home neighborhoods and at trip ends—proved to be highly statistically significant and influential in their impact on all measures of travel behavior. In many cases, balance, mix, and accessibility were found to be more relevant (as measured by elasticities) than several household and traveler characteristics that often form a basis for travel behavior prediction. In contrast, under all but the vehicle ownership models, the impact of density was negligible after accessibility was controlled.
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Lee, Chih-Wei, Feng Tao, Yu-Yu Ma, and Hung-Lung Lin. "Development of Patent Technology Prediction Model Based on Machine Learning." Axioms 11, no. 6 (May 26, 2022): 253. http://dx.doi.org/10.3390/axioms11060253.
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Intellectual property rights have a great impact on the development of the automobile industry. Issues related to the timeliness of patent applications often arise, such as the inability of firms to predict new technologies and patents developed by peers. To find the proper direction of product development, the R&D departments of enterprises need to accurately predict the technology trends. Machine learning adopts calculation through a large amount of data through mathematical models and methods and finds the best solution at the fastest speed through repeated simulation and experiments, to provide decision makers with a reference basis. Therefore, this paper provides accurate forecasts through established models. In terms of the significance of management, the planning of future enterprise strategy can be divided into three stages as a short-term plan of 1–3 years, a medium-term plan of 3–5 years, and a long-term plan of 5–10 years. This study will give appropriate suggestions for the development of automobile industry technology.
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Liu, Jian Feng. "Optimization Simulation of Hybrid Assembly Production Sequencing Management." Advanced Materials Research 850-851 (December 2013): 1008–11. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.1008.
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Sequencing of hybrid assembly production directly affects the balancecontinuity and punctuality of production process. First, the mathematical models with MILP of hybrid assembly production are established, and then the sets of sequencing scheme of minimum makespan which meet customers demands are obtained. Furthermore workshop simulation models with Flexsim software are established. In this paper, the painting hybrid assembly production line of some automobile engine manufacturing plant was employed to analyze the sequencing as an example, and the obtained painting production line sequencing scheme is consistent with the actual production of enterprises and it improves production capacity.
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Mushtaha, Emad, and Faisal Hamid. "Review on Vandalism and Mathematical Models for Visibility and Accessibility in Housing Districts: Case Study Sharjah City." Open House International 42, no. 1 (March 1, 2017): 5–15. http://dx.doi.org/10.1108/ohi-01-2017-b0002.
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In recent times, residential districts in modern cities face certain new and undesired problems related to antisocial behaviour by adolescents in its urban public spaces. In this study, we investigate the relationship between the design features of public spaces in residential areas and the problem of vandalism within the districts. This paper examines the current literature reviews on vandalism, the main reasons behind the increase of in the problem, types of vandalism, and a mathematical model for assessing visibility and accessibility in addition to proving the results of a field study conducted in a UAE city. We believe that visibility of vandalism-prone areas through dwelling windows, accessibility of such areas by residents through dwelling entrances, and recognition of ownership of such areas can definitely play a role in mitigating vandalism. Our findings indicated the following: (1) There is a strong relationship between vandalism and visibility through dwelling windows. (2) Residents' accessibility to dwelling entrances and recognition of ownership play an important role in reducing vandalism. (3) In areas where the visibility and accessibility by residents is low, the severity of the problem of vandalism increase if there is an increase in the percentage of adolescent residents. (4) The design characteristics of the housing areas, such as the height of the blocks or the limits of public spaces, do not have any influence on the occurrence of vandalism.
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Hamed, Mohammad M., and Walid M. Abdelwahab. "Effect of government policies and vehicle marketing strategies on household vehicle demand and fuel consumption." Canadian Journal of Civil Engineering 23, no. 3 (June 1, 1996): 587. http://dx.doi.org/10.1139/l96-867.
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The objective of this paper is to develop demand models to forecast household vehicle demand and corresponding fuel consumption in Jordan. Understanding the factors that influence household vehicle quantity holdings provides a useful tool for developing strategies aimed at curtailing the contribution of automobiles towards environmental pollution, traffic congestion, and traffic accidents in urban areas. The demand for automobile and fuel by a household is simultaneously estimated by a joint discrete and continuous choice model. A multinomial logit model is used to examine the number of vehicles owned by a household, whereas a multiple regression model is used to predict the amount of fuel consumed. A random sample of households from the Greater Amman area is used to estimate demand and choice models. Results suggest that the socioeconomic characteristics of a household, government policies relating to vehicle import duties and vintage, and private sector marketing strategies, all influence a household's decision on the number of vehicles owned. Results strongly show that households with different vehicle ownership levels respond differently to government policies and car dealers' marketing strategies. Policy makers and transportation planners can use the results of this study to forecast the expected demand for used cars, and the increase in the number of new cars, given a set of government and private sector strategies. The results also can be used to predict fuel demand at various levels of household vehicle ownership. Transportation planners can also use these results to assist in formulating strategies regarding urban road network improvements, and future demand for public transportation. Key words: vehicle ownership, fuel consumption, logit model, government policy.
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Jäckel, M., T. Falk, T. Grimm, and D. Prof Landgrebe. "Smart Joining/Smart Joining - Concept for Mechanical Joining 4.0." wt Werkstattstechnik online 106, no. 10 (2016): 705–11. http://dx.doi.org/10.37544/1436-4980-2016-10-31.
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Der Fachbeitrag beschreibt Zusammenhänge zwischen verschiedenen – in einer Automobilproduktion relevanten – Randbedingungen und dem Fügeergebnis beim Halbhohlstanznieten in Form von mathematischen Modellen. Diese Modelle sowie neue Ansätze bei der Fügewerkzeuggestaltung bilden die Grundlage für die dargelegten Konzepte zur Weiterentwicklung der mechanischen Fügetechnik hin zu cyber-physischen Systemen, die mit anderen Prozessen in der Automobilproduktion vernetzt sind. This article describes in mathematical models how various boundary conditions in an automotive production system and the joining result for self-pierce riveting are related. These models and new approaches in the joining tool design are the basis for the described concepts for developing mechanical joining techniques to enable cyber-physical systems linked to other processes in automobile production.
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Rao, Lei, Lian Bing Zhu, Xiao Long Li, and Qi Yao Hu. "The Defects Analysis and Numerical Simulation of Automobile Brake Hydro Cylinder in Permanent Casting." Materials Science Forum 704-705 (December 2011): 82–87. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.82.
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Brake hydro cylinder is the key part of automobile hydraulic braking system, which usually works under high pressure condition. So, high safety factor of it is required to avoid accident. There are many kinds of casting defects such as shrinkage cavity, gas entrapment and slag enclosure are formed in the mold filling and solidification processes, which contribute to final casting performance. Based on the mathematical models of molding filling and solidification processes, the numerical simulation has been done. In the meanwhile, the defects forming reasons have been analyzed. According to the simulation results, two types of improved schemes have been analyzed and practiced respectively, and its work piece defects were reduced largely. It is an effective way to improve the casting quality by advanced computer technology.
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Peng, Yichen, Jing Zhou, Qiang Xu, and Xiaoling Wu. "Cost Allocation in PPP Projects: An Analysis Based on the Theory of “Contracts as Reference Points”." Discrete Dynamics in Nature and Society 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/158765.
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In recent years, the demand for infrastructure has been largely driven by the economic development of many countries. PPP has proved to be an efficient way to draw private capital into public utility construction, where ownership allocation becomes one of the most important clauses to both the government and the private investor. In this paper, we establish mathematical models to analyze the equity allocation problem of PPP projects through a comparison of the models with and without the effects of the theory of “contracts as reference points.” We then derive some important conclusions from the optimal solution of the investment ratio.
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Hubeladze, Iryna. "Methods and organization of research on the realization of sense of ownership in social practices." Організаційна психологія Економічна психологія 1, no. 22 (March 31, 2021): 45–53. http://dx.doi.org/10.31108/2.2021.1.22.5.
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Introduction. Given the lack of methods for studying the sense of ownership, the article substantiates the feasibility and strategy of studying the psychological features of the realization of sense of ownership in social practices. Aim. To develop a set of methods for empirical research of psychological features of realization of person’s sense of ownership in social practices. Methods. A set of qualitative and quantitative methods, which included: associative experiment, focus group method, expert survey, interview, content analysis, mathematical and statistical analyses, as well as factor and correlation analyses to model the features of the realization of sense of ownership in social practices. Results. The set of methods proposed by the author consisted of three groups of methods, which aimed at: 1) determining the most typical social practices of ownership, in which a sense of ownership was manifested; 2) studying social ideas of Ukrainians regarding property; 3) studying the psychological features of the realization of sense of ownership in various social practices and constructing models of this realization. The author gives a logical substantiation of a step-by-step strategy of research into the realization of sense of ownership in social practices. Conclusions. The proposed research strategy and methods allow exploring a complex social and psychological phenomenon of sense of ownership and its realization in social practices. The quantitative and qualitative methods of the mixed research are effective and offer the possibility of generalization of the data by means of auxiliary strategy of triangulation. The proposed research model can be replicated and supplemented in further scientific research depending on the objectives and conditions of the study.
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WALLACE, R., and R. G. WALLACE. "Blowback: new formal perspectives on agriculturally driven pathogen evolution and spread." Epidemiology and Infection 143, no. 10 (February 4, 2014): 2068–80. http://dx.doi.org/10.1017/s0950268814000077.
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SUMMARYBy their diversity in time, space, and mode, traditional and conservation agricultures can create barriers limiting pathogen evolution and spread analogous to a sterilizing temperature. Large-scale monocropping and confined animal feeding-lot operations remove such barriers, resulting, above agroecologically specific thresholds, in the development and wide propagation of novel disease strains. We apply a newly developed class of necessary-conditions statistical models of evolutionary process, first using the theory on an evolutionarily stable viral pathogen vulnerable to vaccine treatment: post-World War II poliomyelitis emerged in the UK and USA from sudden widespread adoption of automobile ownership and usage. We then examine an evolutionarily variable pathogen, swine influenza in North America. The model suggests epidemiological blowback from globalizing intensive husbandry and the raising and shipping of monoculture livestock across increasing expanses, is likely to be far more consequential, driving viral selection for greater virulence and lowered response to biomedical intervention.
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Korolev, M. E. "Computer simulation in informatics lessons as a factor of the continuity of school education in teaching mathematical modeling." Informatics and education, no. 5 (July 16, 2021): 52–58. http://dx.doi.org/10.32517/0234-0453-2021-36-5-52-58.
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The article actualizes the need to use elements of computer modeling from school to university when teaching mathematics to engineering students, analyzes the role of simulation models of applied mathematics. The experience of organizing classes using data visualization is presented, the use of simulators and games for studying mathematics in the context of mathematical education, in which students interact with interactive learning environments, is discussed, examples of using computer simulations in the classroom are discussed. The study lists and characterizes the types of didactic simulations, examines the process of transition of school education using simulators and games into the didactics of mathematics of technical universities using applied mathematics and mathematical modeling to elements of simulation. A pedagogical experiment of the continuity of school education (section “Information systems and programming” of the Donetsk Republican Small Academy of Sciences for Students) was carried out in teaching applied mathematics, informatics and mathematical modeling (the department “Transport technologies”) students of the engineering and transport direction of Automobile and Road Institute of Donetsk National Technical University.
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Efremov, Alexander М., Zufar I. Sadriev, Vladimir V. Nikitin, Ivan V. Kalinin, and Vladimir S. Vlasov. "Total cost of ownership as a base of Transneft fleet operation." SCIENCE & TECHNOLOGIES OIL AND OIL PRODUCTS PIPELINE TRANSPORTATION 10, no. 1 (February 29, 2020): 84–95. http://dx.doi.org/10.28999/2541-9595-2020-10-1-84-95.
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Total cost of ownership (TCO) accounting is a brand new optimization process aimed at gaining overall investment and maintenance benefit which is being first applied in Transneft to vehicles and heavy equipment. Commonly fleet renewal and model choice decisions are built on outdated technical standards, personal experience or declared properties, however such way cannot provide an objective result in a modern condition of engineering. IT development in vehicles and heavy equipment monitoring allows accumulating primary data on the operation of each technical unit. Transneft has worked out the methodology of AV annual TCO calculating and analysis to describe the procedure and methods of applying the primary data to AV annual TCO calculating, optimal equipment lifetime determination and models comparison. The authors of this paper have developed the methodology based on the identification of primary data correspondence to different intervals of the same model lifetime using a Big data logic and further operating cash flow long-term forecasting for each model. Forecasting process is selected between averaging, linear extrapolation and probabilistic model based on reliability theory methods. AV annual TCO is calculated by applying equivalent annual annuity to the overall lifetime cash flow. Optimal equipment lifetime is calculated in correspondence to the minimum AV annual TCO. Models are compared by the AV annual TCO corresponded to optimal equipment lifetime. AV annual TCO calculating and analysis provides a whole new level of optimal equipment lifetime determination based on overall investment and maintenance benefit and models overall lifetime costs comparison. Thus we have a mathematical founded answer to the questions «How often to renew the fleet?» and «Which model to choose?».
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Navin, Francis P. D., Arthur Bergan, and Guanyu Zhang. "Road Safety Model: Some Fundamental Ideas." Transportation Research Record: Journal of the Transportation Research Board 1563, no. 1 (January 1996): 48–57. http://dx.doi.org/10.1177/0361198196156300107.
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A fundamental relationship has been developed that explains road accident statistics in developed and developing countries. The model uses two variables, traffic hazard measured as deaths per vehicle and motorization measured as vehicles per person, to estimate personal hazard as deaths per person. Special cases of the model are those by Smeed, Trinca et al., and Koornstra. The model of fatalities has two extremes. Early motorization has high traffic hazard and personal safety is low and increasing. Full motorization is characterized by a moderate and falling traffic hazard and a low and decreasing personal safety. Between these extremes, there is a maximum number of fatalities per population. Models for personal injury and total road accidents in developed countries appear to follow a similar trend. Available world data fit the proposed relationships well. The models allow planners and engineers to estimate the future maximum road fatalities for developing countries. The model has been extended to incorporate an automobile ownership model that explains some of the growth in motorization. A traffic hazard model is also outlined, in part on the basis of the ideas developed by Koornstra. The extended models should allow a more detailed analysis of some of the social and engineering factors that contribute to road safety.
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WOLFF, Andrzej. "Numerical analysis of piston ring pack operation." Combustion Engines 137, no. 2 (May 1, 2009): 128–41. http://dx.doi.org/10.19206/ce-117191.
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In the paper a model of a piston ring pack motion on an oil film has been analysed. The local oil film thickness can be compared to height of the combined roughness of mating surfaces of piston rings and cylinder liner. Equations describing the mixed lubrication problem based on the empirical mathematical model formulated in works of Patir, Cheng [6, 7] and Greenwood, Tripp [3] have been combined [12] and used in this paper. A model of a gas flow through the labyrinth seal of piston rings has been developed [13, 15]. In addition models of ring twist effects and axial ring motion in piston grooves have been applied [14, 15]. In contrast to the previous papers of the author, an experimental verification of the main parts of developed mathematical model and software has been presented. A relatively good compatibility between the experimental measurements and calculated results has been achieved. In addition this study presents the simulation results for an automobile internal combustion engine
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Jasilionis, Aivaras, Saulius Nagurnas, and Mindaugas Melaika. "USE OF MATHEMATICAL METHODS OF STATISTICS FOR ANALYZING ENGINE CHARACTERISTICS / MATEMATINĖS STATISTIKOS METODŲ TAIKYMAS ANALIZUOJANT VARIKLIŲ TECHNINES CHARAKTERISTIKAS." Mokslas - Lietuvos ateitis 4, no. 4 (November 28, 2012): 351–55. http://dx.doi.org/10.3846/mla.2012.55.
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For the development of new models, automobile manufacturers are trying to come up with optimal software for engine control in all movement modes. However, in this case, a vehicle cannot reach outstanding characteristics in none of them. This is the main reason why modifications in engine control software used for adapting the vehicle for driver’s needs are becoming more and more popular. The article presents a short analysis of development trends towards engine control software. Also, models of mathematical statistics for engine power and torque growth are created. The introduced models give an opportunity to predict the probabilities of engine power or torque growth after individual reprogramming of engine control software. Santrauka Automobilių gamintojai sukurtas degimo variklių valdymo programas pritaiko visiems automobilio judėjimo režimams ir tarp jų siekia optimalaus balanso. Tačiau tuomet automobilis nė vienu režimu nerealizuoja tinkamiausių būtent tam režimui parametrų, todėl labai populiarėja valdymo programos perprogramavimas. Straipsnyje trumpai apžvelgiamos kryptys, kuriomis tobulinami valdymo programų kūrimo metodai. Taip pat pagal eksperimentinių tyrimų metu surinktus duomenis pateikti sudaryti variklio išvystomos galios ir sukimo momento padidėjimo matematinės statistikos modeliai. Sudarant šiuos modelius, nustatytos minimalios ir maksimalios galios ir sukimo momento padidėjimo reikšmės, apskaičiuotos vidutinės reikšmės bei vidutiniai kvadratiniai nuokrypiai, parinkti teoriniai nagrinėjamų duomenų pasiskirstymo dėsniai. Sudaryti matematinės statistikos modeliai leidžia prognozuoti galios ir sukimo momento padidėjimo reikšmės patekimo į tam tikrą intervalą tikimybes.
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Kumbár, Vojtěch, and Artüras Sabaliauskas. "Low-temperature behaviour of the engine oil." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, no. 6 (2013): 1763–67. http://dx.doi.org/10.11118/actaun201361061763.
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The behaviour of engine oil is very important. In this paper has been evaluated temperature dependence kinematic viscosity of engine oils in the low temperatures. Five different commercially distributed engine oils (primarily intended for automobile engines) with viscosity class 0W–40, 5W–40, 10W–40, 15W–40, and 20W–40 have been evaluated. The temperature dependence kinematic viscosity has been observed in the range of temperature from −15 °C to 15 °C (for all oils). Considerable temperature dependence kinematic viscosity was found and demonstrated in case of all samples, which is in accordance with theoretical assumptions and literature data. Mathematical models have been developed and tested. Temperature dependence dynamic viscosity has been modeled using a polynomials 3rd and 4th degree. The proposed models can be used for prediction of flow behaviour of oils. With monitoring and evaluating we can prevent technical and economic losses.
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Kortam, Wael, and Amr Soliman. "Using Extrapolation Techniques of Big Data to Improve the Effectiveness of Sales Forecasting – Empirical Evidence on the Egyptian Passengers Automobile Market." Archives of Business Research 9, no. 4 (April 23, 2021): 91–95. http://dx.doi.org/10.14738/abr.94.10022.
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Sales forecasting is the tactical and strategic trigger for a significant number of crucial functional and management activities. Extrapolation techniques will be used as mathematical tools for demand forecasting, where extrapolation methods estimates or generate values beyond the range of the original set of data. A triangulated approach of experimental essences was applied to data analysis composed of ARIMA, exponential smoothing and grey model GM(1,1). This research is an endeavor to demonstrate the robustness of certain extrapolation models and procedures with a view to word improving the effectiveness of sales forecast in terms of relevance and accuracy. The forecasted sales for both brands is both reserved and yet relatively optimistic. Thus, manifesting the high risk/high return profile of the Egyptian passenger automobile market.
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Sipakov, Rostyslav, Olena Voloshkina, Julia Bereznitska, and Volodimir Trofimovich. "Assessment and forecast for the creation of photochemical smog over transport overpasses in Kyiv." DSpace at USEFUL.academy, no. 2018 (February 23, 2018): 44–51. http://dx.doi.org/10.32557/dsua/20.500.12334/24.
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This article deals with the analysis of existing models of smog situation formation over automobile overpasses and in places of substantial congestion of transport in large cities, for example, in Kyiv. A mathematical model consisting of two blocks – dynamic and kinetic, which allows determining the formation of the thermal dome of pollution and the concentration of hydrocarbon emissions in the air, depending on the number of working engines, is proposed. The kinetic block of the model allows determining the level of formaldehyde, as an indicator of the appearance of photochemical smog in conditions of atmospheric constancy. The concentration of emissions from motor vehicles in the air is calculated over the main transport overpasses of the city of Kyiv at their full load (peak hours).
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Zeng, Cheng, Dong Bo Yang, Li Liu, and Feng Tian Cai. "Modeling and Simulation Research on the Effect of Driving Skills on Vehicle Fuel Efficiency." Advanced Materials Research 512-515 (May 2012): 1167–73. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.1167.
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The research and application of eco-driving has the important practical significance for the energy conservation and emission reduction of automobile industry. In this paper, a simulation model has been set up based on GT-Suite and mathematical models of driving operations to simulate three typical driving operations. The results show that the acceleration speed plays important role in the acceleration operation. As the acceleration speed increases, fuel economy significantly deteriorates. In the transmission operation, the engine should not be operated in the high speed region. Otherwise, the fuel economy would deteriorate. In the cruise operation, the gear should be selected to matching the speed. High-gear low speed operation will cause safety problems, while low-gear high-speed operation will cause significantly deterioration of fuel economy.
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Berechman, J., and K. A. Small. "Research Policy and Review 25. Modeling Land Use and Transportation: An Interpretive Review for Growth Areas." Environment and Planning A: Economy and Space 20, no. 10 (October 1988): 1285–309. http://dx.doi.org/10.1068/a201285.
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Urban growth is taking new forms in recently urbanized or formerly suburban areas, characterized by low density, heavy dependence on automobile transportation, and multiple activity centers. In order to understand better such ‘contemporary urban areas’, researchers need land-use models that realistically capture the key features of such areas and that can handle detailed data sets. We review the literature on large-scale land-use modeling with this objective in mind. Characterizing the known models along several dimensions describing purpose, conceptual basis, mathematical content, and level of detail, we select models that are representative of the range of approaches taken. Six of these are reviewed in detail, and four others are discussed more briefly. We find that the existing literature forces one to choose between tractability and suitability for contemporary urban areas. The key omission in the tractable models is economies of agglomeration that would help explain the emergence of subcenters. Most tractable models also lack a dynamic structure suitable for handling rapid disequilibrium growth. Models that contain these two features are suitable for broad-brush computer simulation, but they cannot be calibrated with real disaggregated land-use data. This conclusion leads to some brief suggestions on directions for future work.
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Rahman, Atiqe Ur, Muhammad Saeed, and Harish Garg. "An innovative decisive framework for optimized agri-automobile evaluation and HRM pattern recognition via possibility fuzzy hypersoft setting." Advances in Mechanical Engineering 14, no. 10 (October 2022): 168781322211321. http://dx.doi.org/10.1177/16878132221132146.
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In multi-attribute decision-making system, decision-makers have to face two kinds of situations: (i) the opted parameters are likely to be classified into their respective parametric-valued sub-collections and (ii) the acceptance degree for approximate opinions of decision-makers is required to be assessed by possibility setting. The literature related to fuzzy soft sets is unable to provide any model which can tackle such situations collectively. Therefore, this study aims to address this scarcity through the development of a novel structure, that is, possibility fuzzy hypersoft set ([Formula: see text]-set). Firstly, the algebraic properties and set-theoretic operations of [Formula: see text]-set are characterized by mathematical illustration. Secondly, two algorithms based on AND and OR-operations of [Formula: see text]-set are proposed and authenticated through application in multi-attribute decision-making real-world problems for the evaluation of agri-automobile and then their suitability is judged through vivid comparison. Thirdly, similarity measures between [Formula: see text]-sets are formulated and validated with the help of application in recruitment-based pattern recognition and its significance is assessed through comparison with most relevant models. Lastly, the advantageous aspects of the proposed structure are analyzed by its comparison with possibility fuzzy soft set-like models by observing some important evaluating features.
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Miss. Sushmita H. Kshirsagar et al. "Review on: Multi - Objective optimization of Composite Automobile over Drive Shaft." International Journal on Recent and Innovation Trends in Computing and Communication 7, no. 3 (March 22, 2019): 44–47. http://dx.doi.org/10.17762/ijritcc.v7i3.5260.
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Composites is increasingly used in different applications in the last decade, especially in aerospace due to their high strength and lightweight characteristics. Indeed, the latest models of Airbus (A350) and Boeing (B787) have employed more than 50 wt% of composites, mainly Carbon Fiber Reinforced Polymers (CFRP). Yet, the increased use of CFRP has raised the environmental concerns about their end-of-life related to waste disposal, consumption of non-renewable resources for manufacturing and the need to recycle CFRP wastes. In this study, generic model is developed in order to propose an optimal management of aerospace CFRP wastes taking into account economic and environmental objectives. Initially, a life-cycle systemic approach is used to model the environmental impacts of CFRP recycling processes focusing on Global Warming Potential (GWP) following the guidelines of Life Cycle Assessment (LCA). The whole supply chain for recycling CFRP pathways is then modeled from aircraft dismantling sites to the reuse of recycled fibers in various applications. A multiobjective optimization strategy based on mathematical programming, ε-constraint and lexicographic methods with appropriate decision-making techniques (M-TOPSIS, PROMETHEE-GAIA) has been developed to determine CFRP waste supply chain configurations. Different scenarios have been studied in order to take account the potential of existing recycling sites in a mono-period visions as well as the deployment of new sites in a multi-period approach considering the case study of France for illustration purpose. The solutions obtained from optimization process allow developing optimal strategies for the implementation of CFRP recovery with recycled fibers (of acceptable quality) for the targeted substitution use while minimizing cost /maximizing profit for an economic criterion and minimizing an environmental impact based on GWP.
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Addo, K. D., and S. M. Sackey. "Demand Forecast Modelling of Vehicles as a Decision Support: The Case of Toyota Ghana." AFRICAN JOURNAL OF APPLIED RESEARCH 8, no. 2 (October 31, 2022): 30–47. http://dx.doi.org/10.26437/ajar.31.10.2022.03.
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Purpose: This purpose of this paper is to develop a mathematical demand forecast model as an alternative to expert-intensive methods for decision support in automobile companies using Toyota Ghana as a case. The paper explores the challenges associated with reliance on experts’ judgment in demand forecasting.
Design/Methodology/Approach: The methodology involved analysing stock reports, lost sales reports, and financial reports from Toyota Ghana to understand the effect of poor forecasting. Using data from two key managers and six sales staff, the project examines the perspectives of staff regarding the use of expert judgment for demand forecasting. Further data was collected via a questionnaire from five authorized automobile distributors and dealerships.
Findings: The results revealed the adverse effects of expert-opinion forecasting, which include irregular stock quantities leading to lost sales, vehicle quality challenges leading to deterioration, and long-term negative impact on profitability. Yet demand forecasting by reliance on experts was very prevalent in the automobile industry. The developed forecast model relies on Mean Absolute Percentage Error with a smoothing constant of 0.4. was validated using recent historical data revealing a 2% variance with actual demand values, while for expert judgment the variation margin was 14%. This strongly indicated that the model yielded more accurate predictions of demand than expert predictions.
Research Limitation: The case-study nature of the study means a more generalized study was still needed before the findings could be more widely applied across the automobile industry.
Practical implication: The study recommended further development of scientific forecasting models for predicting demand across the automobile industry since they carried positive implications for the smooth running of the industry. This could help mitigate the challenges associated with using expert opinions in demand forecasting. Beyond this, the model could serve to provide valuable information to vehicle manufacturers, thereby yielding efficiencies in their value chains.
Social implication: Accurate demand forecasting and management have positive implications for operational efficiency that minimizes customer disappointment.
Originality / Value: The model offers a better alternative for predicting demand more accurately, promoting correct stock holding quantities, avoiding stock deterioration, and reducing expenditure on quality checks, thus ultimately increasing profitability.
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Sui, Tian Zhong, Lei Wang, and Yang Wang. "Flow Filed Simulation Analysis and Structural Optimization of Automotive Catalytic Converter." Advanced Materials Research 945-949 (June 2014): 899–903. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.899.
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Catalytic converter is an important device of automobile engine exhaust system. Based on Hydromechanics, the relational mathematical models of catalytic converter simulation are established and the parameters are calculated. Making use of CFD numerical simulation method, a simulation is set up for the internal flow field of catalytic converter original model using fluent software. From the simulation, the internal flow characteristic is understood. On the basis of this, through the optimization idea adding a guiding device in inlet cone of catalytic converter, the uniformity of velocity of flow is improved. The simulation analysis show that the flow uniformity for internal flow field can be improved observably in the structural optimization, the increasing degree of pressure loss is with little range. A new idea and reference may be offered for improving flow uniformity of a catalytic converter.
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Zhao, Li Jun, Guo Jun Li, and Ji Hai Jiang. "The Study on Optimal Matching of Power System of Hybrid Hydraulic TLT." Advanced Materials Research 97-101 (March 2010): 4403–7. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.4403.
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According to the running characteristic of an aircraft tractor and the specificity of serve target, the hybrid hydraulic system program is proposed. In the use of Adopting Simulated Annealing Genetic Algorithm, for the demand of aircraft tractor’s system, the multi-objective is transformed to a single objective function of the automobile’s dynamic performance and fuel economy performance by using the linear weighted method. Then the mathematical optimizing model of the powertrain is established, through calculating, reasonable parameters are gotten. The analysis of the simulation results shows that the comprehensive performance of the automobile has been remarkably promoted. On the basis of previous work, the system pressure of different weight aircraft models of traction has been optimized in order to give full play to the vehicle's performance. The research has important reference value for the theory analysis of hybrid systems and engineering applications.
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He, Xiaohui, Dongmei Su, Wenchao Cai, Alexandra Pehlken, Guofang Zhang, Aimin Wang, and Jinsheng Xiao. "Influence of Material Selection and Product Design on Automotive Vehicle Recyclability." Sustainability 13, no. 6 (March 19, 2021): 3407. http://dx.doi.org/10.3390/su13063407.
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From 2008 to 2020, Chinese automobile production and sales have ranked first in the world. The huge production, sales, and ownership of automobiles will inevitably lead to a rapid increase of end-of-life vehicles in the future and a corresponding issue of resource recycling. Based on the analysis of a practical dismantling study and statistics declared by the supplier of 19.5% of components and parts with a weight greater than 0.5 kg from two typical vehicle models from 2011 to 2013, this paper focuses on nonmetallic components and parts, the connection of components and parts materials, and the product life cycle of each stage, to find rational technical solutions, and therefore maximize recyclability and recoverability and achieve sustainable development. On one hand, recycling at each stage for vehicles is considered in the design and development of products. As a result, it is found that the main methods, which are conducive to recycling, are increasing the use ratio of materials that are easy to recycle. In addition, general principles of material selection are summarized. On the other hand, vehicles’ dismantling is considered in the initial stage of product design and methods of structural design are summarized.
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Gim, Tae-Hyoung Tommy. "Analysing the Effects of Land Use on the Choice of Intra-Zonal Trip Destinations – A Comparison Between Weekday and Weekend Travel." Promet - Traffic&Transportation 32, no. 4 (July 9, 2020): 527–42. http://dx.doi.org/10.7307/ptt.v32i4.3399.
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Among the studies on the land use – travel relationship, few investigated it regarding weekend travel and destination choice. This study accordingly evaluates how the land use - destination choice relationship differs between weekdays and weekends using two multinomial logistic regression models in which the destination is classified into three types: microzone inside, microzone outside - macrozone inside, and macrozone outside. Major findings are that the choice of automobile alternatives for travel and their ownership are associated with the choice of the microzone inside while employment and income contribute to external trips. Among land use variables, nighttime population density turns out to be the only land use variable that consistently increases internal trips in all cases, regardless of the zone size and weekday - weekend difference, whereas daytime population density does not become significant in any case. Also, land use entropy and street connectivity are found to discourage a trip that moves from the microzone to the macrozone and transit system variables to facilitate a trip that goes beyond the microzone. Particularly, between two types of transit system variables, the choice of the microzone is likely to be associated with low bus stop density on weekdays and low metro station density on weekends.