scholarly journals Planning simulation experiments in problems of studying operational strategies of container terminals

2020 ◽  
Vol 2020 (4) ◽  
pp. 105-112
Author(s):  
Alexander Lvovich Kuznetsov ◽  
Alexander Viktorovich Kirichenko ◽  
Anton Denisovich Semenov ◽  
Anna Aleksandrovna Radchenko
Keyword(s):  
Optimality Criterion ◽  
Simulation Modelling ◽  
Operating Conditions ◽  
Container Terminals ◽  
Operational Strategies ◽  
Container Stacking ◽  
Insufficient Amount ◽  
Short Period ◽  
The Given ◽  
Selection Of

The article describes the problem of the effectiveness of different container stacking strategies, which has been the matter of research in many scientific works. The methods of substantiating the strategies vary from mathematical calculations to practical application. There has been set the task to prove the adequacy of the new container stacking strategy. The application of different strategies for container terminals is found not reliable due to rapid changes of operating conditions and insufficient amount of data that can be collected for the short period of a strategy application. It is proved that the only reliable method that provides the independent proof of the efficiency of container stacking strategies is simulation modelling. Special attention in the studies should be given to planning of the experiments. To compare the strategies it is proposed to use multiple experiments with different parameters of the incoming and outgoing traffic. There is presented a case of comparison of strategies for finding a minimum over the entire stack and stacking containers based on their shelf life. When analyzing the strategies for storing containers it is necessary to determine the optimality criterion, since the attractiveness of a particular strategy will depend on the selected optimized parameter. As a criterion of optimality in the given example, the complexity of the selection of containers is taken, which is determined by the average number of movements required to select one container. It is justified that according to the optimality criterion, the best strategy takes into account the storage periods of containers.

Application of the turbidity ratio method in the spherical particle size determination in the range m ∈ and α ∈

1979 ◽  
Vol 44 (7) ◽  
pp. 2064-2078 ◽  
Author(s):  
Blahoslav Sedláček ◽  
Břetislav Verner ◽  
Miroslav Bárta ◽  
Karel Zimmermann
Keyword(s):  
Refractive Index ◽  
Spherical Particle ◽  
Ratio Method ◽  
Refractive Indices ◽  
Relative Refractive Index ◽  
Particle Size Determination ◽  
The Individual ◽  
The Given ◽  
Turbidity Ratio ◽  
Selection Of

Basic scattering functions were used in a novel calculation of the turbidity ratios for particles having the relative refractive index m = 1.001, 1.005 (0.005) 1.315 and the size α = 0.05 (0.05) 6.00 (0.10) 15.00 (0.50) 70.00 (1.00) 100, where α = πL/λ, L is the diameter of the spherical particle, λ = Λ/μ1 is the wavelength of light in a medium with the refractive index μ1 and Λ is the wavelength of light in vacuo. The data are tabulated for the wavelength λ = 546.1/μw = 409.357 nm, where μw is the refractive index of water. A procedure has been suggested how to extend the applicability of Tables to various refractive indices of the medium and to various turbidity ratios τa/τb obtained with the individual pairs of wavelengths λa and λb. The selection of these pairs is bound to the sequence condition λa = λ0χa and λb = λ0χb, in which b-a = δ = 1, 2, 3; a = -2, -1, 0, 1, 2, ..., b = a + δ = -1, 0, 1, 2, ...; λ0 = λa=0 = 326.675 nm; χ = 546.1 : 435.8 = 1.2531 is the quotient of the given sequence.

Adaptation Application to Engine Modelling

2007 ◽  
Author(s):  
Jude Iyinbor
Keyword(s):  
Measurement Data ◽  
Engine Performance ◽  
Performance Model ◽  
Operating Conditions ◽  
Adaptation Process ◽  
Design Point ◽  
Component Map ◽  
Important Measurement ◽  
Unknown Component ◽  
Selection Of

The optimisation of engine performance by predictive means can help save cost and reduce environmental pollution. This can be achieved by developing a performance model which depicts the operating conditions of a given engine. Such models can also be used for diagnostic and prognostic purposes. Creating such models requires a method that can cope with the lack of component parameters and some important measurement data. This kind of method is said to be adaptive since it predicts unknown component parameters that match available target measurement data. In this paper an industrial aeroderivative gas turbine has been modelled at design and off-design points using an adaptation approach. At design point, a sensitivity analysis has been used to evaluate the relationships between the available target performance parameters and the unknown component parameters. This ensured the proper selection of parameters for the adaptation process which led to a minimisation of the adaptation error and a comprehensive prediction of the unknown component and available target parameters. At off-design point, the adaptation process predicted component map scaling factors necessary to match available off-design point performance data.

scholarly journals Dynamic Mechanical Fatigue Behavior of Polymer Electrolyte Membranes for Fuel Cell Electric Vehicles Using a Gas Pressure-Loaded Blister

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4177
Author(s):  
Jun Hyun Lim ◽  
Jian Hou ◽  
Chang Hyun Lee
Keyword(s):  
Proton Conductivity ◽  
Hydrogen Gas ◽  
Gas Pressure ◽  
Operating Conditions ◽  
Mechanical Resistance ◽  
Dynamic Mechanical ◽  
Mechanical Fatigue ◽  
Aging Test ◽  
Short Period ◽  
Mechanical Aging

This study reports on an innovative press-loaded blister hybrid system equipped with gas-chromatography (PBS-GC) that is designed to evaluate the mechanical fatigue of two representative types of commercial Nafion membranes under relevant PEMFC operating conditions (e.g., simultaneously controlling temperature and humidity). The influences of various applied pressures (50 kPa, 100 kPa, etc.) and blistering gas types (hydrogen, oxygen, etc.) on the mechanical resistance loss are systematically investigated. The results evidently indicate that hydrogen gas is a more effective blistering gas for inducing dynamic mechanical losses of PEM. The changes in proton conductivity are also measured before and after hydrogen gas pressure-loaded blistering. After performing the mechanical aging test, a decrease in proton conductivity was confirmed, which was also interpreted using small angle X-ray scattering (SAXS) analysis. Finally, an accelerated dynamic mechanical aging test is performed using the homemade PBS-GC system, where the hydrogen permeability rate increases significantly when the membrane is pressure-loaded blistering for 10 min, suggesting notable mechanical fatigue of the PEM. In summary, this PBS-GC system developed in-house clearly demonstrates its capability of screening and characterizing various membrane candidates in a relatively short period of time (<1.5 h at 50 kPa versus 200 h).

scholarly journals Material Origins of Accelerated Operational Wear of RD-33 Engine Blades

2020 ◽  
Author(s):  
Adam Kozakiewicz ◽  
Stanislaw Jóźwiak ◽  
Przemysław Jóźwiak ◽  
Stanisław Kachel
Keyword(s):  
Chemical Composition ◽  
Construction Material ◽  
Operating Conditions ◽  
Design Stage ◽  
Strength Analysis ◽  
Jet Engine ◽  
Emergency Situations ◽  
Low Pressure Turbine ◽  
Propulsion Unit ◽  
Selection Of

The structural and strength analysis of the material used to construct such an important engine element as the turbine is of great significance, both at the design stage as well as during tests and expertises related to emergency situations. Bearing in mind the conditions above mentioned, the paper presents the results of research on the chemical composition, morphology and phased structure of the metallic construction material used to produce the blades of the high and low pressure turbine of the RD-33 jet engine, which is the propulsion unit of the MiG-29 aircraft. The data obtained as a result of the material tests of the blades allowed, on the basis of the analysis of chemical composition and phased structure, to determine the grade of the alloy used to construct the tested elements of the jet engine turbine. The structural stability of the material was found to be lower in comparison with engine operating conditions, which manifested itself as a clear decrease in the resistance properties of the blade material. The results obtained can be used as a basis for analyzing the life span of an object or a selection of material replacements, which enable to produce the analyzed engine element.

scholarly journals The Business Service Sector in India, Ireland and Poland. A Comparative Analysis

2019 ◽  
Vol 22 (2) ◽  
pp. 159-172
Author(s):  
Arkadiusz Mroczek
Keyword(s):  
Comparative Analysis ◽  
Service Sector ◽  
Operating Conditions ◽  
Business Service ◽  
Literature Study ◽  
Location Factors ◽  
Current Growth ◽  
Characteristic Features ◽  
Selection Of ◽  
Made In

The fast growth of the service sector is one of the characteristic features of the contemporary economy. Amongst other CEE countries, Poland is one of the emerging locations for this sector. The aim of the paper is to examine and compare the business service sector in India, Ireland and Poland. Both India and Ireland are exceptional locations for this industry, so comparing the state and operating conditions in Poland with those countries can be insightful. A literature study is used to determine the motives of companies undertaking offshore investments, upon which a selection of location factors is made. In the empirical part, those factors are analyzed in a descriptive way. This allows us to draw conclusions concerning this sector in Poland. This country, to some extent, possesses selected positive features of both India and Ireland, which explains the current growth of the sector.

scholarly journals THE STYLISTIC FUNCTIONING OF SCRIPTURAL ALLUSIONS IN AN EARLY MODERN ENGLISH PLAY “JOHAN BAPTYSTES PREACHYNGE” BY J. BALE

2020 ◽  
Vol 30 (6) ◽  
pp. 1001-1007
Author(s):  
A.A. Khavronich
Keyword(s):  
Early Modern ◽  
Early Modern English ◽  
Semantic Expansion ◽  
Early English ◽  
The Given ◽  
Selection Of

The given article analyzes the peculiarities of the stylistic functioning of allusions to the Holy Scripture within one religious play belonging to the modern early English period, namely “Johan Baptystes Preachynge” produced by a dramatist J. Bale. The analysis is performed from the standpoint of linguopoetics. We consider stylistic features via the correlation of form and meaning, dissection of the conceptual component, juxtaposition with medieval plays representing adaptations of the same scriptural plot. Within the framework of this analysis we identify and assess elements performing the function of impact incorporated into the scriptural allusions and estimate their role in the selection of other lexical units, construction of extended metaphors, syntactic shaping of particular fragments of the play. We draw a conclusion that via the extension of scriptural metaphorical complexes the author brings about a meaningful focus shift to ensure a protestant reinterpretation of the included biblical theses. A substantial share of stylistically marked elements undergoes semantic expansion and develops adherent connotations since they relate to the pivotal elements of the allusions.

scholarly journals Selection of the variant solution of forest road alignment conceptual design using multicriteria optimisation

2009 ◽  
pp. 165-176 ◽  
Author(s):  
Bogdan Stefanovic ◽  
Ivan Bjelanovic
Keyword(s):  
Conceptual Design ◽  
Multicriteria Optimization ◽  
Linear Distribution ◽  
Forest Road ◽  
Multicriteria Optimisation ◽  
Technical Production ◽  
The Given ◽  
Selection Of ◽  
Design Construction ◽  
Building Parameters

One of the three studied variant solutions of forest road conceptual design was selected based on the linear distribution of criteria, as the method of multicriteria optimization. The selection was performed with 25 parameters classified as economic, technical, production and social criteria. The parameters of technical criteria were grouped into design, construction and building parameters. Based on calculated nominal values of parameters by the given criteria, their ranking, comparison, point rating and scoring, the selected most favorable solution was variant 1.

scholarly journals THEORETICAL RESEARCH OF THE POSSIBILITY OF JOINTLESS TRACK ARRANGEMENT IN CURVED SECTIONS OF RADIUS LESS THAN 350 METERS

2021 ◽  
Vol 1 (37) ◽  
pp. 86-96
Author(s):  
V. Tverdomed
Keyword(s):  
Theoretical Calculations ◽  
Operating Conditions ◽  
Theoretical Research ◽  
Track Structure ◽  
Method Of Determination ◽  
Traditional Structure ◽  
Transverse Stability ◽  
The Given ◽  
Current Operating

The traditional structure of the upper structure of the track on the main railways of Ukraine in curved sections with a radius of less than 350 m is a link structure of the track with wooden sleepers. This track design is not rational under current operating conditions. The use of a more advanced jointless track design in curves with a radius of less than 350 m is limited primarily by the condition of ensuring the transverse stability of the rail-sleeper lattice. To be able to expand the use of jointless track construction in curved sections with a radius of less than 350 m, it is necessary to know the values of the transverse forces of interaction of the structures of the upper track structure with the moving carriage. Knowing the forces of interaction, it is possible to estimate by what value the transverse stability of the rail-sleeper lattice will be provided and to make constructive decisions on its increase. The method of determination of transverse horizontal forces of interaction of track and moving carriage in curves of radius less than 350 m taking into account quasi-static compressive forces in a train is given. The reasons for these forces are related to the presence of eccentricity of the autoclutch shank in the horizontal and vertical planes. Theoretical calculations of horizontal transverse forces of interaction are carried out according to the given technique and coefficients of stability of a rail-sleeper lattice in curved sites are defined. The main conclusions concerning the possibility of operation of the jointless track structure in curved sections with a radius of 350 m and less are made.

scholarly journals Vulnerability analysis and method of selection of communication protocols for information transfer in Internet of Things systems

2021 ◽  
pp. 133-149
Author(s):  
Maryna Kolisnyk
Keyword(s):  
Internet Of Things ◽  
Initial Data ◽  
Information Transfer ◽  
System Analysis ◽  
Communication Protocols ◽  
Critical Systems ◽  
Smart Objects ◽  
Corporate System ◽  
The Given ◽  
Selection Of

The subject of study in the paper is the analysis of technologies, architectures, vulnerabilities and cyberattacks, communication patterns of smart objects, messaging models, and Internet of Things (IoT) / Web of Things (WoT) protocols for solving applied problems of critical and non-critical systems. The goal is to develop a method for selecting messaging models and application-level protocols in non-critical and critical multi-level IoT/WoT systems, provided that the type of access to intelligent objects is initially determined by the initial data, as well as analysis of vulnerabilities and attacks using these protocols. Objectives: to formalize the procedure for choosing communication protocols for IoT/WoT systems; analyze possible vulnerabilities of communication protocols; develop a method for selecting communication protocols for given initial data, depending on the selected type of communication template for smart objects; check practically the proposed method. The methods of research are methods of system analysis. The following results were obtained. The analysis of the features of communication protocols is conducted by comparing the main interrelated characteristics of IoT/WoT, the results of which are presented in the form of a table. A method has been developed for selecting communication protocols, depending on the selected type of communication template. The analysis of possible vulnerabilities of communication protocols and possible attacks using these protocols is conducted. The author has tested the method using the example of a corporate system (Smart House) based on the WoT concept. Findings. The scientific novelty of the results obtained is as follows: the analysis conducted in the paper shows that currently there is no unified approach to the choice of a messaging model and application-level protocols for building IoT/WoT, depending on the selected type of communication template for smart objects. The method for selecting communication protocols for the given conditions (for each IoT system its interaction pattern will correspond, depending on which components interact with each other), improved by the authors of the paper, makes it possible to simplify the task of using separate protocols for given IoT systems, considering vulnerabilities of protocols.

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