scholarly journals SELECTION OF INTERVAL FOR BRAKING TIME PARTIONING TO DETERMINE THE BRAKING DISTANCE OF A FREIGHT TRAIN

2020 ◽  
pp. 58-63
Author(s):  
O.G Makeieva ◽  
Keyword(s):  
Time Intervals ◽  
Freight Train ◽  
Time Value ◽  
A Value ◽  
Method Of Determination ◽  
Maximum Value ◽  
Train Operation ◽  
Braking Distance ◽  
Selection Of

According to GOST 34434-2018 the brake distance of the freight train is determined by summing up increase of the brake distance at intervals of the braking time. Value of the braking distance will depend on the value of the temporary interval at which the braking time is divided from the begging of the braking to the full stop of the freight train. For this reason it is necessary to choose the temporary interval value at which calculated braking distance of the freight train will correspond to real values. The task was solved by the method of determination of the freight train braking distance for a given range of the intervals values Δti: from (0,07 – 1,2) with a step of 0,01 s and 0,1 s. It is shown that a value of the temporary interval influences the braking distance. The range of interval values was determined (0,07 – 0,1) s, at which braking distances have the maximum value for preserving stability, with this it was determined that beyond the range the values of braking distances were decreased. Integration of the differential equation of the freight train operation ac-cording to the new rules is performed by summing up increases of the braking distance at braking time intervals. It was proposed to determine the braking distance of the freight train according to the temporary interval which is 0,1 s.

scholarly journals Algorithm for selecting motor and trailer cars in a freight train of motor-car traction according to the energy efficiency criterion

2020 ◽  
Vol 6 (1) ◽  
pp. 104-119 ◽  
Author(s):  
Pavel S. Troitskiy
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Energy System ◽  
Control Algorithms ◽  
Efficiency Criterion ◽  
Freight Train ◽  
Traction Motors ◽  
Perishable Goods ◽  
Train Operation ◽  
Selection Of

Background: improving the efficiency of freight transport is one of the main challenges facing the world's Railways. One of the most effective solutions is the introduction of distributed motor-car cargo traction. This will significantly increase the operational efficiency of the train's power plant, improve its handling, reduce the amount of destructive impact on the track, increase the capacity of railway lines and the reliability of deliveries of perishable goods. When considering the allocation algorithm for operating the traction motors (TED) on the composition of a diesel freight trains subject to the conditions of alignment resource all TED motor coaches concluded the possibility of increasing the efficiency of multimotor traction drive modular freight trains using the proposed control algorithms for energy efficiency. Aim: formalization of the task of selecting motor and trailer cars in a modular electric freight train. Methods: In article the algorithm of selection of motor and trailer cars on a freight train railcar traction on the criterion of energy efficiency, the benefits of adopting a modular truck trains, are the main prerequisites for the implementation of distributed railcar truck pull. The work is based on the theory of traction calculations for train operation and is aimed at ensuring safe and energy-efficient traffic along the route sections. Results: The developed algorithm of selection of motor and trailer cars in a unit train freight based on the condition of ensuring the traction and coupling properties of the train on the current upgrades, the development of the total volume of cargo offered for transport and energy efficiency of this type of traction. When using the proposed algorithms for managing the energy efficiency of a motor-car electric train by selecting motor and trailer cars, adjusting the power, number of traction engines and their distribution by the composition of the traun, energy consumption on the Medvezhya Gora Noviy Poselok section can be reduced by 20.5% in the direction there and by 18.9% in the direction back without changing the traffic schedule. And when compared with a locomotive-hauled train that regulates energy consumption using the same algorithm by 4.49% and 3.61%, respectively. Energy consumption on the Krivenkovskaya Goitkh section can be reduced by 16% in the direction there and by 82% in the direction back without changing the traffic schedule. And when compared with a locomotive-hauled train that regulates energy consumption by the same algorithm by 1.61% and 65.92%, respectively. Conclusions: The author proposes an algorithm for selecting motor and trailer cars in a freight train of motor-car traction according to the criterion of energy efficiency with the condition of ensuring traction and coupling properties on the calculated lifts. As well as the algorithm of distribution of working traction engines by the composition of the freight trains, taking into account the requirement of equalizing the resource of their work, preventing overheating and hypothermia of the fuel and energy system, and improving train handling.

scholarly journals Absurdism and Generation Z Humor: the Effects of Absurdist Content on Perceived Humor Levels in Generation Z Students

2021 ◽  
Vol 10 (4) ◽  
Author(s):  
Chloe Partlow ◽  
Patricia Talarczyk
Keyword(s):  
High School ◽  
Likert Scale ◽  
Likert Scales ◽  
Generation Z ◽  
A Value ◽  
Maximum Value ◽  
Chi Squared ◽  
The Relationship ◽  
Increasing Function ◽  
Selection Of

This study investigated the relationship between absurd humor in meme stills and the perceived humor among Generation Z students. Students of a high school in Northeast Ohio were given one of two seemingly identical surveys, each with a selection of six memes and individual Likert scales corresponding to the presented memes. A rubric was created with guidelines for visual components that was used to assign the presented memes an absurdity score with categories of “minimal absurdism,” “semi-absurd,” and “absurd.” Participants (n=298)  were asked to rank the memes on the Likert scale ranging from a value of 1—not at all funny to a maximum value of 5—extremely funny. Following a chi-squared test, we can be over 99% confident that there is a present relationship between absurdist humor content in meme stills and how humorous they are rated by Generation Z students. These findings can be applied to the usage of memes in marketing, an ever-increasing function of meme humor, to make advertisements and communication more effective.

Application of methods for analysing combinations of wheelset sizes and switch elements to determine the size of gutters of check-rail assemblies

2021 ◽  
pp. 3-9
Author(s):  
B. E. Glyuzberg ◽  
◽  
A. A. Loktev ◽  
V. V. Korolev ◽  
V. S. Kuskov ◽  
...  
Keyword(s):  
Cross Sections ◽  
Accurate Method ◽  
The Other ◽  
Conditional Probabilities ◽  
Rail Wear ◽  
Method Of Determination ◽  
Train Operation ◽  
Motion Paths ◽  
The One

The paper considers methods for analysis of size combinations of wheelsets and elements of switches that are used at determination of dimensions of gutters for check-rail assemblies. The method of limit combinations, from the one side, doesn’t guarantee a reliable train operation on crossing assemblies in real operation, but, from the other side, it makes unreasonably strict demands to the design of the assembly. In order to eliminate the contradictions the paper proposes to use a method of probable compositions that allows not only solving an issue of limited safe dimensions of gauge and gutters, but also determining repeatability of impacts on check-rails in the most loaded cross sections and repeatability of motion paths of wheels on crossing. However, while using this method the authors have revealed a number of contradictions between calculated results and real operation. They show that it is possible to avoid the contradictions by the use of conditional probabilities method that allows calculating probabilities of phenomena for specific size combinations of gauge and gutters. As a result, the authors have concluded that it is the most accurate method of determination of permissible dimensions for gauge and gutters on switches. With the use of the method the authors have determined the maximal values of check-rail wear for straight track made of SP special profiles in conditions of nonexceedance of «impact effect» in bent part of the check-rail for switches with various angles.

scholarly journals Some aspects of topology and kinematics of a 3DOF translational parallel mechanism

2014 ◽  
Vol 19 (1) ◽  
pp. 5-15 ◽  
Author(s):  
J. Bałchanowski
Keyword(s):  
Kinematic Analysis ◽  
Inverse Kinematics ◽  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Analytical Procedure ◽  
Method Of Determination ◽  
Fixed Orientation ◽  
Three Degrees Of Freedom ◽  
Selection Of

Abstract The paper presents elements of the topology, geometry and the kinematic analysis of a translational parallel mechanism with three degrees of freedom. In such mechanisms the selection of a proper structure and geometry ensures that the driven link maintains a fixed orientation relative to the base. The method of determination of the configuration of mechanisms using contour vector notation was elaborated in the paper. The equations for the analysis of the direct and inverse kinematics task are determined. An analytical procedure for determining the system’s singular positions is presented and illustrated with examples

scholarly journals Implementasi Algoritma Smarter for the Determination of the Thesis Supervisor

2021 ◽  
Author(s):  
Tan Kim Hek
Keyword(s):  
Decision Making ◽  
Rank Order ◽  
Visual Basic ◽  
Sql Server ◽  
Utility Value ◽  
Mathematical Procedure ◽  
A Value ◽  
Sql Server 2005 ◽  
Selection Of

Decision making is a basis for determination / unanimity that has a value or criteria that have a weight that can describe a person's ability and intellectual (Ananta dan Winiarti, 2013)..This study aims to design and implement a simple multi attribute attribute rating technique exploiting rank (SMARTER) for the determination of the supervisor lecturer. This SMARTER method is a multi-criteria method which consists of several criteria where each criterion contains values and weights that are used to compare the values between the criteria for lecturers and others. The calculation method data is analyzed and designed using the Rank-Order Centroid (ROC) method with a simple mathematical procedure and produces a major priority of several attributes in the form of a range. The results of the study can be concluded that the greatest utility value of each lecturer can be determined as a supervisor. This system only discusses the selection of thesis supervisors and there is no gender separation for students and supervisors. The database uses SQL Server 2005 and programming using the Visual Basic 2008 language.

scholarly journals DETERMINATION OF FREIGHT WAGON PARAMETERS ACCORDING TO THE SPECIFIED CRITERIA OF THE TRAIN BRAKING EFFICIENCY (four-axle gondola cars, covered cars, platforms, dump cars)

2021 ◽  
pp. 101-110
Author(s):  
Oleksandr Safronov ◽  
◽  
Yurii Vodiannikov ◽  
Olena Makeieva
Keyword(s):  
Axial Load ◽  
Gear Ratio ◽  
Normative Values ◽  
Power Relationship ◽  
Freight Train ◽  
Braking Performance ◽  
Brake Pads ◽  
Braking System ◽  
Braking Distance

The lack of normative values of the actual coefficients in the new rules of HOST 34434-2018 do not allow to implement and determine the optimal characte-ristics of the brake according to pre-accepted conditions of braking efficiency (braking distance), which causes uncertainty in solving this problem. The uncertainty is that the choice of characteristics of the braking system of the freight wagon has to be done by searching a large number of options. In this regard, the paper provides tools for determining the actual pressing force of the brake pads on the wheels, which complies with the specified braking performance of the freight train. As a tool, universal formulas are used in the form of a power relationship between the actual force of the brake pads and the braking distance of the freight train. The coefficients of universal formulas are obtained on the basis of computer modeling. Numerous examples show that the error in the use of universal formulas in calculation studies does not exceed 1% compared with the calculation method according to HOST 34434-2018. The values of the actual coefficients depending on the axial load of the wagon and the speed at which the braking distances of the freight train satisfy the normative minimum allowable values are given. It is shown that calculation studies performed according to the universal formulas in the EXCEL environment allows to fully automating the computational process. A method for determining the gear ratio of the brake lever of a freight wagon, according to which the specified braking efficiency is performed, is proposed. The proposed procedure allows you to perform a variety of studies to select the optimal parameters of the braking system of freight wagons that meet the specified requirements of braking efficiency, and greatly facilitates the calculation studies. Key words: аctual coefficient, braking distance, speed, axial load, power dependence, coefficients, gear ratio.

Vitamin A Value of Plant Food Provitamin A - Evaluated by the Stable Isotope Technologies

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 25-29 ◽  
Author(s):  
Guangwen Tang
Keyword(s):  
Stable Isotope ◽  
Vitamin A ◽  
Provitamin A ◽  
Animal Origin ◽  
Plant Food ◽  
Plant Foods ◽  
A Value ◽  
Provitamin A Carotenoids ◽  
Β Carotene

Humans need vitamin A and obtain essential vitamin A by conversion of plant foods rich in provitamin A and/or absorption of preformed vitamin A from foods of animal origin. The determination of the vitamin A value of plant foods rich in provitamin A is important but has challenges. The aim of this paper is to review the progress over last 80 years following the discovery on the conversion of β-carotene to vitamin A and the various techniques including stable isotope technologies that have been developed to determine vitamin A values of plant provitamin A (mainly β-carotene). These include applications from using radioactive β-carotene and vitamin A, depletion-repletion with vitamin A and β-carotene, and measuring postprandial chylomicron fractions after feeding a β-carotene rich diet, to using stable isotopes as tracers to follow the absorption and conversion of plant food provitamin A carotenoids (mainly β-carotene) in humans. These approaches have greatly promoted our understanding of the absorption and conversion of β-carotene to vitamin A. Stable isotope labeled plant foods are useful for determining the overall bioavailability of provitamin A carotenoids from specific foods. Locally obtained plant foods can provide vitamin A and prevent deficiency of vitamin A, a remaining worldwide concern.

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu.

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Camilo Fuentes Serrano ◽  
Juan Reinaldo Estevez Alvares ◽  
Alfredo Montero Alvarez ◽  
Ivan Pupo Gonzales ◽  
Zahily Herrero Fernandez ◽  
...  
Keyword(s):  
Thin Layer ◽  
Expanded Uncertainty ◽  
Considerable Decrease ◽  
X Ray ◽  
Precipitation Efficiency ◽  
Method Of Determination ◽  
Sensitivity Curves ◽  
Order Of Magnitude ◽  
Metrological Parameters

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).

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