THE PROCEDURE FOR CALCULATION OF THE OPTIMAL CARRYING CAPACITY OF PUSHED CONVOY BASED ON PARAMETERS OBTAINED BY EXPERIMENTS IN ACTUAL NAVIGATING CONDITIONS

Exploitation and technical parameters of a ship are very important qualitative characteristics which determine the efficiency of the use of any kind of transportation vessels both for pushboats and for pushed convoys as a whole. Some of the most important exploitation and technical parameters are: parameter of transport efficiency, tonnage quality parameter, and thrust output of propeller. The complexity of these parameters can be seen from the fact that they present the values of achieved payload-distance during transportation of cargo in the unit of time per unit of installed (or effective) power of propelling engines of ships. The most reliable means for determining the transport efficiency is the method of testing in actual navigating conditions, which is conducted in order to determine exact technical characteristics of propelling engines of pushboats, and to determine drawbacks in their work and to increase their thrust and speed characteristics. This paper will present the process of choosing the size, shape, and number of barges in the convoy based on experiments conducted on a pushboat whose propelling engines have installed power 3×809.6 kW (3×1,100 HP). Obtained results are based on presumption that the total resistance of a pushed convoy is equal to the total thrust achieved by the ship’s propelling complex

The golden ratio in probablistic and artificial intelligence

Problem linijskog odsječka utemeljenog na omjeru zlatnog reza φ = 1,618033 ima analogiju u vjerojatnosti. Rješenje elementarne eksponencijalne raspodjele, posebice ističe vrijednost 2lnφ. Ova vrijednost također ima ključnu ulogu u odnosu Rikatijevih hiperboličnih funkcija s Fibonačijevim i Lukasovim brojevima u kontinuiranom području. Time se uspostavlja bliska veza između konstanti e i φ. Izvedena su dva nova teorema o konvergenciji konstanti φ i e . Broj e je temelj Markovskih procesa, koji su našli primjenu u teoriji vjerojatnosni i umjetne inteligencije. Omjer konstanti e i φ, kao i mnogi drugi prirodni fenomeni na temelju zlatnog reza, ističu potrebu za proširenjem područja vjerojatnosni i umjetne inteligencije.The problem of the line section based on the golden ratio φ = 1,618033 has the analogy in probability. The solution of the elementary exponential distribution relies on the value 2lnφ in particular. This value also plays a key role to Riccati hyperbolic functions with Fibonacci and Lucas numbers in continuous domain. This establishes a close relationship between the constants e and φ. Two new theorems on the convergence between the constants φ and e were derived. The number e is the foundation of Markov processes, which find applications in probabilistic and artificial intelligence theory. The ratio between the constants φ and e, as well as many other natural phenomena based on the golden ratio, highlight the need to expand the field of probabilistic and artificial intelligence

Fuzzy Multicriteria Model for Ranking Suppliers in Manufacturing Company

By using the methods of multi-criteria analysis it is possible to make decisions which have significant influence on companies\u27 business. The aim of this paper is to evaluate different suppliers using the integrated model that recognizes a combination of fuzzy AHP (Analytical Hierarchy Process) and the COPRAS method. Based on six criteria, the expert team was formed to compare them, so determination of their significance is being done with fuzzy AHP method. Expert team also compares suppliers according to each criterion and on the base of triangular fuzzy numbers. Based on their inputs, COPRAS method is used to estimate potential solutions. Suggested model accomplishes certain advantages in comparison with previously used traditional models which were used to make decisions about evaluation and choice of supplier. It is vital to make the right decision when selecting a supplier, because the optimal choice ensures lower cost and higher quality of the product itself, and therefore more competitiveness in the market. This work is licensed under a&nbsp;Creative Commons Attribution-NonCommercial 4.0 International License.</p

Application of Statistical Analysis for Risk Estimate of Railway Accidents and Traffic Incidents at Level Crossings

Abstract This paper deals with applying statistical analysis of traffic safety to analyze the risks at level crossings. The social costs of railway accidents and traffic incidents at level crossings are very high and lead to a reduction in the levels of traffic safety. In addition to the consequences reflected in the loss of human lives, injuries, and disabilities, the stress and trauma of direct participants in traffic, accidents, and incidents at level crossings cause huge property and economic losses and significant primary and secondary traffic delays. The traffic safety analysis was conducted on 2128 level crossings, which are differently protected on the lines Joint Stock Company for Public Railway Infrastructure Management ”Serbian Railway Infrastructure” with statistical data of accidents in the Republic of Serbia from 2007 to 2017. The paper analyzes the obtained results using the methods of descriptive and inferential statistics to define measures of possible improvement of safety levels at the obtained critical level crossings. Also, a proposal was made for improving and raising the level of safety on level crossings through innovative education of direct participants in traffic

Fuzzy Multicriteria Model for Ranking Suppliers in Manufacturing Company

By using the methods of multi-criteria analysis it is possible to make decisions which have significant influence on companies\u27 business. The aim of this paper is to evaluate different suppliers using the integrated model that recognizes a combination of fuzzy AHP (Analytical Hierarchy Process) and the COPRAS method. Based on six criteria, the expert team was formed to compare them, so determination of their significance is being done with fuzzy AHP method. Expert team also compares suppliers according to each criterion and on the base of triangular fuzzy numbers. Based on their inputs, COPRAS method is used to estimate potential solutions. Suggested model accomplishes certain advantages in comparison with previously used traditional models which were used to make decisions about evaluation and choice of supplier. It is vital to make the right decision when selecting a supplier, because the optimal choice ensures lower cost and higher quality of the product itself, and therefore more competitiveness in the market. This work is licensed under a&nbsp;Creative Commons Attribution-NonCommercial 4.0 International License.</p

Mathematical identification of influential parameters on the elastic buckling of variable geometry plate

The problem of elastic stability of plates with square, rectangular, and circular holes as well as slotted holes was discussed. The existence of the hole reduces the deformation energy of the plate and it affects the redistribution of stress flow in comparison to a uniform plate which causes a change of the external operation of compressive forces. The distribution of compressive force is defined as the approximate model of plane state of stress. The significant parameters of elastic stability compared to the uniform plate, including the dominant role of the shape, size, and orientation of the hole were identified. Comparative analysis of the shape of the hole was carried out on the data from the literature, which are based on different approaches and methods. Qualitative and quantitative accordance of the results has been found out and it verifies exposed methodology as applicable in the study of the phenomenon of elastic stability. Sensitivity factor is defined that is proportional to the reciprocal value of the buckling coefficient and it is a measure of sensitivity of plate to the existence of the hole. Mechanism of loss of stability is interpreted through the absorption of the external operation, induced by the shape of the hole

AN INTEGRATED DECISION-MAKING MODEL FOR EFFICIENCY ANALYSIS OF THE FORKLIFTS IN WAREHOUSING SYSTEMS

In the logistics world, special attention should be given to warehousing systems, cost rationalization, and improvement of all the factors that affect efficiency and contribute to smooth functioning of logistics subsystems. In real time industrial practice, the issue of evaluating and selecting the most appropriate forklift involves a complex decision-making problem that should be formulated through an efficient analytical model. The forklifts efficiency plays a very important role in the company. The forklifts are being used on a daily basis and no logistical processes could be done without them. Therefore, it has been decided to determine their efficiency, which will contribute to the optimization of the process in this logistics subsystem. This study puts forward an integrated forklift selection model using Data Envelopment Analysis (DEA), Full Consistency Method (FUCOM) and Measurement Alternatives and Ranking According to the Compromise Solution (MARCOS) methods. Five input parameters (regular servicing costs, fuel costs, exceptional servicing costs, total number of all minor accidents and damage caused by forklifts) and one output parameter (number of operating hours) were first identified to assess efficiency of eight forklifts in a warehousing system of the Natron-Hayat company using the DEA model. This step allows sorting of efficient forklifts which are subsequently evaluated and ranked using FUCOM and MARCOS methods. A sensitivity analysis is also performed in order to check reliability and accuracy of the results. The findings of this research clearly show that the proposed decision-making model can significantly contribute to all spheres of business applications

IMPACT OF THE NUMBER OF VEHICLES ON TRAFFIC SAFETY: MULTIPHASE MODELING

Traffic safety is one of the key issues nowadays, given the fact that a large number of people lose their lives in traffic accidents every day. There are various influential factors in the occurrence of traffic accidents, the number of vehicles being one of them. This paper assesses the traffic safety in Montenegro in the period 1998-2020 by applying the multiphase modeling with a purpose to obtain comparative results which enable implementation of adequate strategies. A total of six scenarios were formed with two inputs and two outputs in a DEA (Data Envelopment Analysis) model, with the number of registered vehicles per year being an input in all scenarios. In addition, as inputs, the scenarios included AADT (Annual Average Daily Traffic), passengers in road transport, passenger-km by road transport, goods transported by road, tone-km by road, and passengers in local transport. The number of traffic accidents with casualties, the number of traffic accidents with material damage, the number of fatal cases and the number of injured persons, depending on a scenario, were observed as outputs. After the DEA model, IMF SWARA (Improved Fuzzy Stepwise Weight Assessment Ratio Analysis) was applied to determine the weights of inputs and outputs, while the final state of traffic safety by years was determined using the MARCOS (Measurement of alternatives and ranking according to COmpromise solution) method