Heuristic methods for routing and scheduling

A locomotive assignment is one of the subproblems in railway scheduling domain. In this report present general mathematical model of this specific subproblem and describe how methods known from other problems domain like traveling salesman problem, operation research and constraint programming can be used to solve it. We concentrate especially on method known as {\it k--interchange} for traveling salesman problem with time windows and give an outline how it can be adopted to locomotive assignment problem. Further, while turning from one trip to another a locomotive must often be reallocated from one station to another. This can be performed in two ways. A locomotive can be driven from one place to another not performing any specific trip and exclusively using track resource, i.e. performs so called deadhead transport, or can be attached to any other transport and passively drown to another station, i.e. perform so called passive transport. Because the cost of passive transport is much lower then cost of a deadhead it is advantageous to, if possible, replace any deadhead by passive transport. In this report we describe a method of converting deadheads into passive transports, describe conversion algorithm, its implementation and report computational result of the algorithm. Finally, we give directions for future research in locomotive planning problem domain

Track train dynamics analysis and test program: Methodology development for the derailment safety analysis of six-axle locomotives

The operational safety of six axle locomotives is analyzed. A locomotive model with corresponding data on suspension characteristics, a method of track defect characterization, and a method of characterizing operational safety are used. A user oriented software package was developed as part of the methodology and was used to study the effect (on operational safety) of various locomotive parameters and operational conditions such as speed, tractive effort, and track curvature. The operational safety of three different locomotive designs was investigated

Sizing and Energy Management of a Hybrid Locomotive Based on Flywheel and Accumulators

The French National Railways Company (SNCF) is interested in the design of a hybrid locomotive based on various storage devices (accumulator, flywheel, and ultracapacitor) and fed by a diesel generator. This paper particularly deals with the integration of a flywheel device as a storage element with a reduced-power diesel generator and accumulators on the hybrid locomotive. First, a power flow model of energy-storage elements (flywheel and accumulator) is developed to achieve the design of the whole traction system. Then, two energy-management strategies based on a frequency approach are proposed. The first strategy led us to a bad exploitation of the flywheel, whereas the second strategy provides an optimal sizing of the storage device. Finally, a comparative study of the proposed structure with a flywheel and the existing structure of the locomotive (diesel generator, accumulators, and ultracapacitors) is presented

Locomotive syndrome presents a risk for falls and fractures in the elderly Japanese population

Abstract“Locomotive syndrome” is used to designate the condition of individuals with musculoskeletal disease who are highly likely to require nursing care. This article reviews screening, prevalence, causal and related factors, and the relationship between locomotive syndrome and falls and fractures in older adults with this syndrome. A few self-administered questionnaire tools are available to assess individuals for locomotive syndrome. Additionally, screening methods, including a physical functioning assessment, are appropriate for detailed discrimination of locomotive syndrome. The prevalence of locomotive syndrome is significantly higher in women than in men, and tends to increase markedly from 70 years of age. More severe locomotive syndrome is related to knee pain, osteoporosis, sarcopenia, and lumbar disease. The incidence of falling in locomotive syndrome is higher than the incidence for the older population in general. Locomotive training including squats and a unipedal standing exercise has been recommending to prevent locomotive syndrome. This training improves muscle strength and balance function for older people who have a risk for locomotive syndrome

Janka Hescheles’ 'Locomotive' (to Bełżec)

This article concerns the influence of the most famous Polish poem for children: Lokomotywa by Julian Tuwim, particularly in three “Holocaust” paraphrases of this work, written by children in the ghetto and the concentration camps – the poems Lokomotywa by Jerzy Ogórek, Pociągu świst by Jerzy Orłowski, and especially Bełżec by Janka Hescheles.Zadanie „Stworzenie anglojęzycznych wersji wydawanych publikacji” finansowane w ramach umowy nr 948/P-DUN/2016 ze środków Ministra Nauki i Szkolnictwa Wyższego przeznaczonych na działalność upowszechniającą naukę

An overview of a Lagrangian method for analysis of animal wake dynamics

The fluid dynamic analysis of animal wakes is becoming increasingly popular in studies of animal swimming and flying, due in part to the development of quantitative flow visualization techniques such as digital particle imaging velocimetry (DPIV). In most studies, quasi-steady flow is assumed and the flow analysis is based on velocity and/or vorticity fields measured at a single time instant during the stroke cycle. The assumption of quasi-steady flow leads to neglect of unsteady (time-dependent) wake vortex added-mass effects, which can contribute significantly to the instantaneous locomotive forces. In this paper we review a Lagrangian approach recently introduced to determine unsteady wake vortex structure by tracking the trajectories of individual fluid particles in the flow, rather than by analyzing the velocity/vorticity fields at fixed locations and single instants in time as in the Eulerian perspective. Once the momentum of the wake vortex and its added mass are determined, the corresponding unsteady locomotive forces can be quantified. Unlike previous studies that estimated the time-averaged forces over the stroke cycle, this approach enables study of how instantaneous locomotive forces evolve over time. The utility of this method for analyses of DPIV velocity measurements is explored, with the goal of demonstrating its applicability to data that are typically available to investigators studying animal swimming and flying. The methods are equally applicable to computational fluid dynamics studies where velocity field calculations are available

A weakly universal cellular automaton in the pentagrid with five states

In this paper, we construct a cellular automaton on the pentagrid which is planar, weakly universal and which have five states only. This result much improves the best result which was with nine statesComment: 23 pages, 21 figure

New applications for phosphoric acid fuel cells

New applications for phosphoric acid fuel cells were identified and evaluated. Candidates considered included all possibilities except grid connected electric utility applications, on site total energy systems, industrial cogeneration, opportunistic use of waste hydrogen, space and military applications, and applications smaller than 10 kW. Applications identified were screened, with the most promising subjected to technical and economic evaluation using a fuel cell and conventional power system data base developed in the study. The most promising applications appear to be the underground mine locomotive and the railroad locomotive. Also interesting are power for robotic submersibles and Arctic villages. The mine locomotive is particularly attractive since it is expected that the fuel cell could command a very high price and still be competitive with the conventionally used battery system. The railroad locomotive's attractiveness results from the (smaller) premium price which the fuel cell could command over the conventional diesel electric system based on its superior fuel efficiency, and on the large size of this market and the accompanying opportunities for manufacturing economy