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This paper aims to investigate the rebound process and the secondary-impact process of the fuselage section that occurs in the actual crash events.

A full-scale three-dimensional finite element model of the fuselage section was developed to carry out the dynamic simulations. The rebound process was simulated by removing the impact surface at a certain point, while the secondary-impact process was simulated by striking the impact surface against the fuselage bottom after the first impact.

For the rebound process, the fuselage structure restores deformation due to the springback of the fuselage bottom, and it results in structural vibration of the fuselage section. For the secondary-impact process, the fuselage deformation is similar with that of the single impact process, indicating that the intermittent impact loading has little influence on the overall deformation of the fuselage section. The strut failure is the determining factor to the acceleration responses for both the rebound process and the secondary-impact process.

The rebound process and the secondary-impact process, which is difficult to study by experiments, was investigated by finite element simulations. The structure deformations and acceleration responses were obtained, and they can provide guidance for the crashworthy design of fuselage structures.

This research first investigated the rebound process and the secondary-impact process of the fuselage section. The absence of the ground load and the secondary-impact was simulated by controlling the impact surface, which is a new simulating method and has not been used in the previous research.

This study analyses the effect of fuel efficiency increase on travel demand in the city of Berlin. Vehicle technologies such as advanced driver assistance systems can help drivers to save fuel and thus lower exhaust emissions on a network level. In order to obtain high political endorsement among different stakeholders, the analysis of such effects which have an impact on overall fuel and emission savings are highly relevant. Recent testing of so called advanced driver assistance systems showed their ability to reduce fuel consumption and lower traffic emissions by giving driving recommendations to drivers.

Two effects on driving were simulated using a travel demand model: the increase in fuel prices which will take place in the coming years and a possible increase in vehicle fuel efficiency. Comparing these scenarios allowed us to calculate the effect of price change and the rebound effect of fuel efficiency gains using standard methods for transport elasticities. The simulation was run with the travel demand model TAPAS and the city of Berlin was the network used as a case study.

As fuel prices increase over time, driving tends to decrease. Driving increases, however, if vehicles become more fuel efficient and the result is the observed rebound effect. On a city network level, this also translates to lower emission savings than expected from the vehicle fuel efficiency gains. The rebound effect which we estimated matches similar findings in the literature, specifically in terms of their magnitude.

We used a simulation to compare scenarios of city travel demand. The result allowed us to estimate changes to the desired variables of fuel efficiency and fuel prices. For those interested in the effects of vehicle efficiency gains on city level these results are highly recommended for consideration.

The proposed framework for analysing rebound effects helped to assess the impacts of energy efficiency technologies on a city level.

Technological progress is a determining factor in the factors leading to economic and social well-being. Simultaneously, the development of a sustainable economy is based on the conservation of resources. In the energy sector, this fact can be corroborated with the reduction of energy consumption, thus increasing economic efficiency. On the one hand, improving energy efficiency contributes to increasing the quality of life, productivity, and, implicitly, the economy, but on the other hand, it leads to excess energy use – this behavioral change is known as rebound. The research estimates the rebound effect at the macroeconomic level for European countries in the period 2000–2019, referring the analysis to each country's gross domestic product (GDP) and energy consumption, as well as comparing the preaccession and postaccession periods of Romania in the EU space. The rebound effect is determined using multidimensional analysis methods, depending on the GDP of each country as well as the behavior of each in the use of energy resources in industry, agriculture, and services. Although the study results confirm the strong link between energy consumption and GDP at the level of each state, they did not show considerable changes between countries at the level of the two periods.

The purpose of this paper is to examine whether the underserved area requirements for Fannie Mae and Freddie Mac (the government-sponsored enterprises [GSEs]) and the community needs requirements of the Community Reinvestment Act (CRA) contributed to the house price run-up in the USA.

This paper predicts the incidence of “Rebounds”, which indicate that a mortgage had been previously denied, to provide evidence on whether certain regulations caused excessively risky mortgage originations. As a different lender rejected the loan given the interest rate that they were willing to charge and information on the borrower, a higher incidence of Rebounds provides evidence that lenders were more frequently disagreeing about loans. This can indicate differences in regulatory pressure or oversight across lenders.

This paper provides evidence that the GSEs were purchasing fewer Rebounds directly from lenders. However, evidence suggests that indirectly, the securitization market served as a conduit for Rebounds to the GSEs that needed to satisfy regulatory underserved area requirements. The necessity of complying with the CRA was found to increase Rebounds. Among regulators, the Federal Reserve was found to have been particularly associated with Rebounds.

The paper’s contribution comes from linking Rebounds to legislative and regulatory influences. This contributes to the literature on excess credit and fraud, as well as the effect of underserved area requirements and the CRA. Also, this paper adds a new dimension to the literature on securitization, by showing the influence of regulation on the securitization of risky mortgages.

The purpose of this paper is to develop a numerical model used for calculating the nonlinearities of large-scale hydro-pneumatic suspension (HPS) and investigating the effects of variations in flow path and operational parameter on suspension damping response.

To parameterization nonlinearities of the suspension, the author developed a two-phase flow model of a large-scale HPS based on computational fluid dynamics and volume of fluid method. Considerable effort was made to verify the nonlinearities by field measurements carried out on an off-highway mining dump truck. The investigation of effects of variations in flow path and operational parameter on damping characteristics highlights the necessity of the numerical simulation.

The two-phase flow model can represent the gas-oil interaction and simulate the suspension operational movement conveniently. Transient numerical simulation results can be used to model the nonlinearities of large-scale HPS accurately. A new phenomenon was discovered that the pressure in rebound chamber presents reduction trend during compression stroke in special cases. It has never been reported before.

Developed a two-phase flow model of a large-scale HPS, which can manage the gas-oil interaction and capture the complex flow field structure in it. The paper is the first study to model the nonlinearities of a large-scale HPS used in off-highway mining dump truck through transient numerical simulation. Compared with previous researches, such a research not only gives new insight and thorough understanding into the suspension internal fluid structure but also can give good guiding opinions to the optimal design of HPS.

The shock absorber is an important component of vehicle suspension that attenuates the vehicle vibration. Its running state directly affects the performance of the vehicle suspension. The purpose of this paper is to quantitatively study the relationship between damping characteristics and air chamber and oil properties in single-tube pneumatic shock absorber.

Combined with the principle of fluid dynamics and hydraulic transmission technology, the rebound stroke and compression stroke mathematical models, and damping characteristics simulation model are established to investigate the effect of the air chamber and oil property on damping characteristics.

Research results show that the initial pressure of the air chamber is the key parameter which influences the damping characteristics of the shock absorber. The change of the initial pressure has more impact on damping force, and less impact on the speed characteristic; the initial volume of the air chamber almost has no effect on the damping characteristics. The density and viscosity of the oil have certain influence on the damping characteristics. Therefore, selecting suitable damping oil is very important.

Using Matlab/Simulink software to build simulation models, its results are very accurate. The conclusions can provide a theoretical reference for the structure design of a single-tube pneumatic shock absorber.

The purpose of this paper is to provide an assessment of the effects of fuel efficiency improvements on four‐wheeler ownership, fuel consumption, fuel imports and emissions for personal transportation in the context of India. The paper also aims to measure the rebound effect induced by this policy.

The paper relies on a system dynamics model to analyse the problem. A causal loop model was developed initially, which was transformed to a stock and flow diagram. Simulation was carried out to capture the effects of fuel efficiency improvements in the four‐wheeler sector of India.

The study has revealed that a policy of fuel efficiency improvements is favourable to the Indian four‐wheeler sector growth, but this policy could result in an increase in fuel consumption and therefore a corresponding increase in the fuel imports and emissions in the country. This policy also induces direct rebound effect that adds up to the already alarming fuel consumption levels.

The study is limited to four‐wheeler passenger cars in India and gasoline as the transport fuel.

The paper offers a system dynamics model that can aid the government, vehicle manufacturers, and environment protection groups to further analyse policies regarding fuel efficiency improvements, fuel price adjustments, four‐wheeler ownership, energy consumption and emission, and to obtain some useful policy insights before those policies are implemented.

This paper aims to examine technology-based firms that successfully turned around a decline in performance, to report what they did and what characterized the firms themselves, relating those actions and characteristics to effective rebounds.

The authors use published data, including financial data, to examine 59 successful rebounds, and then apply regression analyses to relate firm actions and characteristics to performance.

Strategic moves by these firms included layoffs, new products and new inter-company relationships. However, none of those actions predicted rebound success, either individually or in combination. Successful rebounds were associated only with smaller size and a deeper decline – from exceeding the industry performance median to falling far below it.

Technology firms may or may not represent all middle-aged companies in terms of authors’ implications, that a one-size-fits-all turnaround formula is unavailable.

Wise managers will therefore consider various scenarios to prepare for decline and test several if possible. Further, the finding that dramatic drops in performance are associated with successful rebounds should warn managers who think that a competitor’s major problems mean they will disappear; they may be likelier to rebound than a competitor experiencing only a mild performance decline.

Managers who think they have THE answer to decline can profit from the news that one cannot count on layoffs, on new products or on new relationships to turn around performance decline. And, the small-is-beautiful (for rebounds) result suggests rethinking the assumption that bigger is better and making organizational changes in large organizations to allow them to imitate the flexibility advantages that a smaller firm achieves.

The purpose of this paper is to present a novel assembly spring-back model which takes surface contact conditions between sheet metal parts into consideration so that the assembly dimensions and variations can be more precisely predicted than existing assembly simulation models.

Because an assembly process is composed of four essential steps, i.e. locating, clamping, joining and tool releasing, the mechanistic models associated with these steps are developed in the paper. In particular, the surface contact between the weld flanges (in folding joint configuration) and the overlapping surfaces (in lap joint configurations) is included in the models. Sensitivity models are developed.

Two cases studies are presented, i.e. the cantilever beams assembly and the Z-plates assembly. More precise prediction results are shown.

The model developed in this paper is based upon analytical elastic beam theories. Therefore, the results and case studies are limited only to workpieces that can be approximately represented by beam geometries. However, the methods can be broadened to generic workpiece geometries by using finite element methods; thus, the developed method is highly valuable to a broad range of applications such as automotive body assembly and aerospace industries.

The novelty of this research lies in its inclusion of surface contact conditions in an assembly simulation model by using analytical beam mechanistic models to achieve more accurate assembly variation predictions.