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This paper is an endeavor to quantify the concept of sustainable transportation. The prevailing idea in the context of sustainable development (SD) emphasizes on the reduction of transportation demand in order to reduce the environmental and social consequences of it. Nevertheless, in the current paper using a measure for SD and based on the conformity of the growths of all sectors with transportation supply and demand, the countries are comparatively studied. The measure, elasticity, for each two variables indicates the extent to which those two variables have been changing consistently. Indeed the elasticity values are measures of a "harmonic development" representing sustainability. The... 

This study tries to characterize national transportation modes to assess balancing and sustainability. Using a pioneer measure for sustainable development (SD), and based on the conformity of the growths of all sectors with transportation modes, the countries are comparatively studied. The proposed measure, elasticity, for each pair of variables indicates the extent to which the two variables have been changing consistently. Indeed the elasticity values are measures of "harmonic development" reflecting sustainability. The study database consisted of key aspects of transportation sustainability in the form of national variables including transportation, economic, social and environmental... 

We give an algorithm to construct a translation-invariant transport kernel between two arbitrary ergodic stationary random measures on Rd, given that they have equal intensities.As a result, this yields a construction of a shift-coupling of an arbitrary ergodic stationary random measure and its Palm version.This algorithm constructs the transport kernel in a deterministic manner given a pair of realizations of the two measures.The (non-constructive) existence of such a transport kernel was proved in [9].Our algorithm is a generalization of the work of [3], in which a construction is provided for the Lebesgue measure and an ergodic simple point process.In the general case, we limit ourselves... 

A growing number of parents accompany their children to and from school, to make sure they travel with the best care and minimum stress. Policies that aim at promoting nonmotorized modes of transportation or at least discouraging auto driving solely for the purpose of picking up or dropping off the kids may not be successful in practice unless primary concerns of parents are treated appropriately. School escorting decisions need to be investigated, as a decreasing trend in students' travel freedom also decreases the tendency toward the use of active modes of travel, complicates intrahousehold activities that need to be considered in travel demand models, and increases externalities (e.g.,... 

This study is an attempt to quantify the concept of sustainable transportation. The countries are comparatively studied using a pioneer measure for Sustainable Development (SD) and elasticity, that reflects the conformity and harmony of the growths of all sectors with passenger and freight transportation. Firstly, the elasticity of the non-transportation variables, with respect to passenger and freight transportation ones, were developed. Using individual elasticities, composite sustainability indices were suggested. Then, utilizing the Data Envelopment Analysis (DEA) technique, two composite indices, as well as the national variables, are employed to achieve a unique SD efficiency score.... 

The electron transport characteristics of a 1,10-dimethylene-1,10-dicarba-closo-decaborane (10-vertex carborane) single molecular conductor is investigated via the density functional-based non-equilibrium Green's function (DFT-NEGF) method. We consider three configurations for the molecular wire sandwiched between two Au(1 0 0) electrodes: the hollow site, top site and bridge site positions. Our results show that the energetically favorable hollow site configuration has a higher current intensity than the other configurations. The projection of the density of states (PDOS) and the transmission coefficients T(E) of the two-probe system at zero bias are analyzed, and it suggests that the... 

Equity in distribution is one of the most controversial and essential concepts which for a long time has been the central concern of political philosophers when considering planning concerns of the societies. Transport is a key field by which politicians and decision-makers impose their intention on societies. Although there have been studies discussing equity in transport, yet there is no clear mathematical framework to utilize the equity concept in transportation planning. This study has reviewed equity in transportation, as well as in human science studies to investigate and determine how transportation advantages should be equitably distributed among society members. This review has led... 

We consider a setting in which a rail infrastructure provider divides the track costs proportionally between the above-rail operators based on their usage. We study a proposed access charge regime aimed at incentivizing the operators to use longer train configurations. The regime sets a target length and gives a discount on an operator’s charge if it deploys a configuration of at least the target. That is, the operators may be able to reduce their access charges by deploying a longer train configuration. We analyze the policy, and conditions under which both operators have an incentive to deploy long train configurations. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature and EURO... 

We analyze the role of bath temperature, coherence and entanglement on excitation transfer in a spin chain induced by the environment. In Markovian regime, we show that coherence and entanglement are very sensitive to bath temperature and vanish in time in contrary to the case of having zero-temperature bath. That is while, finding the last qubit of the chain in excited state increases by increasing the bath temperature. The obtained results show the destructive role of temperature on coherence and entanglement and confirm that these quantum mechanical features cannot affect probability of finding the last qubit in excited state. © 2019, Isfahan University of Technology. All rights reserved  

We analyze the role of bath temperature, coherence and entanglement on excitation transfer in a spin chain induced by the environment. In Markovian regime, we show that coherence and entanglement are very sensitive to bath temperature and vanish in time in contrary to the case of having zero-temperature bath. That is while, finding the last qubit of the chain in excited state increases by increasing the bath temperature. The obtained results show the destructive role of temperature on coherence and entanglement and confirm that these quantum mechanical features cannot affect probability of finding the last qubit in excited state. © 2019, Isfahan University of Technology. All rights reserved  

In this study a Monte Carlo simulation was used to investigate the effect of cell reactivities and particle diffusivities in the cells and matrix on the diffusion and reaction rate constants in gel-immobilized cell systems with different spatial cell configurations. A variety of conditions were examined ranging from instantaneous to very slow reactions with reaction probabilities equal to or less than one, and diffusivity ratios bigger or smaller than one in a spherical domain. In the case of high reactivity (diffusion-limited), the simulation results indicated a decrease in the reaction rate constants when heterogeneity in the cell distribution was increased. In the case of low reactivity... 

The nonlinear capacitance in doped nanotube junctions is calculated self consistently. A negative differential capacitance is observed when the applied bias becomes larger than the pseudogap of the metallic armchair nanotube. For this device, one can deduce a relaxation time of approximately 0.1 fs. Because of its negative differential resistance (NDR), a switching time of less than a femtosecond, i.e., at least three orders smaller than present-day switching times, can also be estimated. This effect is important in designing ultrafast nano-electronic components. ©2005 The Physical Society of Japan  

Electrodeposition/dissolution of cadmium onto a film of mercury shows some deviations from the natural liquidity of mercury caused by the reduction of Cd onto it. Percolation and fractal analyzes were done on the surface and the bulk of the mercury film during diffusion of Cd species (atoms). These show that the fractal dimensions of the Cd-inserted mercury film are about 2.11 and 2.54 near the surface of the mercury film and at deeper points inside the film, respectively. The insertion process has a negligible effect on the surface morphology of the mercury film and there is a phase transition in the bulk, as well as a geometrical transition during the Cd-insertion (de-insertion) process.... 

The American Association of State Highway and Transportation Officials (AASHTO) and Federal Highway Administration (FHWA) encourage the use of various Accelerated Bridge Construction (ABC) strategies, which can help reduce onsite construction time, minimize traffic and environmental impacts, improve work zone safety, and deliver longer lasting and more durable bridges. ABC approaches include the application of technical innovations and management techniques. The decision to use ABC must be made on a project-by-project basis as each bridge location is unique, and factors constraining each project are different. Toward this end, FHWA developed a qualitative decision making framework called... 

A solution to the imbalance of vehicles in one-way carsharing systems is vehicle relocation which involves staff members to redistribute the vehicles between stations. Vehicle relocation, however, can lead to an imbalance of staff members between stations. Thus, staff members, themselves, need to be relocated between stations to perform the vehicle relocations. This study addresses the joint optimization of vehicle relocation and staff rebalancing using two integrated multi-traveling salesman formulations. Results show that fleet size is more sensitive to demand than staff size, staff size is inversely related to vehicle cost, and that vehicle relocation time increases with vehicle cost  

This paper is an endeavor to picture excessive population threats to the resiliency of a large metropolitan area. By employing an existing evolutionary model of traffic flow on a small expository network, we show how chaotic situations occur at certain demand and supply parameter values and try to address the questions: How may one determine city population capacity for its transportation network, what happens if the city passes this limit, or how may one return the city to a stable situation when it runs into unstable or chaotic situations. Under certain assumptions, the paper designs a simulation experiment to revisit the phenomenon discovered by Greenshields in 1934, but for a... 

This paper considers a two-level supply chain consisting of one warehouse and one retailer. Unlike the most similar models which determine the optimal ordering policy according to inventory cost only, in this model, we also consider the transportation cost. We assume that the demand rate at the retailer is known and the demand is confined to a single item. Shortages are allowed neither at the retailer nor at the warehouse. The objective is to find the economic order quantities for both the retailer and the warehouse which minimize the total cost. That is. the sum of the holding and ordering cost at the retailer and warehouse as well as the transportation cost from warehouse to retailer.... 

This paper proposes a new method for solving the time-dependent neutron transport equation based on nodal discretization using the MCNPX code. Most valid nodal codes are based on the diffusion theory with differences in approximating the leakage term until now. However, the Monte Carlo (MC) method is able to estimate transport parameters without approximations usual in diffusion method. Therefore, improving the nodal approach via the MC techniques can substantially reduce the errors caused by diffusion approximations. In the proposed method, the reactor core is divided into nodes of arbitrary dimensions, and all terms of the transport equation e.g. interaction rates and leakage ratio are... 

This paper aims to propose an approach based on NSGA-II for solving multi-objective non-linear fixed charge transportation problem with multiple modes of transport in crisp and interval environments. Certain modifications need to be made in the existing NSGA-II configuration to calculate the crowding distance of a solution in the interval environment. Besides, a crossover and a mutation scheme suitable for multiple modes of transportation are developed. In the end, a set of test problems are solved in both environments and some comparative studies are performed restricting the problem to only one mode of transport at a time. Finally, the results of the proposed algorithm are compared with...