The sequential method of emptying and filling of ballast tanks at sea may pose extra threats for ship’s safety. The prepared Ballast Water Management (BWM) Plan enables carrying out the operation so that negative effects of emptying each ballast tank are minimized. A large number of tanks and substantial volume of ballast water to be exchanged may create difficulties in preparing an optimized plan. The author proposes to use a liquid cargo handling simulator for the preparation of the BWM plan for selected LNG carriers

Problems concerning preliminary design of FPSO vessels are presented in view of their seakeeping ability. The article analyzes the presently applied approach in which seakeeping quality of FPSO vessels is taken into consideration and discusses possibilities of using this approach at the preliminary stage of design. Besides, the current approach used for predicting such phenomena as heaving, slamming and green water loading is discusse

An attempt is made to build a knowledge data base to be used a basis for a navigational situation assessment system. The system is based on Bayesian networks. A research experiment will be described, in which simulation tests were carried out to define a relevant data base. This article also presents a model for manoeuvre identification and a simulator application created for simulation tests. It has been proved that automatic identification of ships manoeuvres is possible and, so is the navigational situation assessment in view of navigational safety

The failure data available for power, navigation, propulsion and steering systems onboard LNG carriers, during critical manoeuvres in the final harbour and berth approach phase, are often accompanied with a high degree of uncertainty. For this reason the use of conventional probabilistic risk assessment methods may not be well suited. The approach described uses fault tree analysis to calculate the fuzzy probability of systems failure. The risks associated with failure events are determined by combining their occurrence likelihood (probability) and possible consequences to produce a risk ranking

One of the essential issues in the multi-criteria process of voyage planning is the safety of personnel, cargo and the ship itself, accounting for the optimized voyage time and costs. Apart from sometimes difficult weather and navigational conditions, pirates have been a new major threat to the safety of navigation since the beginning of this century. It is because of piracy, traditional routes of vessels differ from seasonal ones, and their threat is taken into consideration in decisions concerning the choice of the sea route of a ship. This article indicates the most dangerous routes in terms of pirate attacks occurrence over the last few years in the Indian Ocean. An attempt is made to relate the number of pirate attacks to hydrometeorological conditions and to define the effect of pirates activities on the problems of choosing the vessel sea route

The article presents the mathematical model of the air brake system with two commonly used valves: the dual circuit foot brake valve and the relay valve. The system can be seen as a part of a typical brake system of heavy trucks. The model has been developed based on the previously elaborated and experimentally verified models of the components of the air brake systems. The model can be used at a design stage to predict the behavior of the system during the normal operation and during the sudden braking or malfunction. Differential equations of pressure changes in the chambers and motion equations of the pistons of membrane operated cylinders as well as algebraic equilibrium equations describing the motion of the moving parts of the brake and relay valves are presented. The values of all model parameters, such as, spring stiffnesses and pistons’ diameters, etc. have been determined by dismantling the valve or referenced from the literature. The experimental verification of the model is planned in the future

This paper presents an example of applying Markov decision process to model and analyse the bus operation and maintenance process within an urban transport system and to forecast the influence of the operation and maintenance strategies realised for the technical objects on the transport system behaviour. Setting the values of the indices describing the process under the analysis is performed on the basis of a computerised simulation of the Markov decision process, being a mathematical model of the technical objects operation and maintenance process. In order to simulate the operation and maintenance process (Markov decision process) and to evaluate the influence of the decisions being made on the course and effectiveness of the process being realised within the study object a simulation algorithm has been elaborated and a computer calculation program has been written. The model presented herein has been created in such a way to assure that it shall be possible to use it in as extensive as possible class of the problems regarding the operation and maintenance of the technical objects

In the article there have been presented the current state and perspectives in the scope of using rapeseed biomass, with particular consideration of solid biodegradable by-products of the technology of obtaining oils- -expellers and rapeseed meal. Rapeseed biomass has been characterised with respect to its technological properties essential in combustion processes, both after conversion into bio-char and bio-oil and with respect to its raw, unprocessed form. The reasonableness of applying this kind of agrobiomass in co-combustion with minable fuels has been shown, resulting from conditions of agricultural production, increasing rapeseed production and by-products, with their incomplete use in the land, in view of the obligatory increased participation of biomass in the structure of fuels applied for producing electric and heat energy. The current state of agrobiomass supply logistics to the boiler plant has been analysed, pointing out its significance in shaping demand satisfaction for biomass using rapeseed waste products

The study refers to questionnaires in which on the basis of scoring of each question, it can be concluded about a formulated research hypothesis. The following paper examines ways of developing, instituting and analyzing surveys in order to accept or reject stated hypothesis. In particular the focus is on measuring credibility of answers provided by participants in the survey. Each answer is scored along two criteria: person’s credibility and significance of the question. The final score is a weighted average of those two variables. This method is particularly useful in surveys when anonymity of participants is not sufficient to guarantee a credible response

The need of being competitive and will to meet clients’ needs makes organizations form mining branch improve their actions. There is a wide variety of system-like solutions for such organizations, such as: quality management system, environment management system, and security and safety management system and social responsibility system. The tendency of implementing and connecting some of the above mentioned solutions has resulted in the integrated management systems. An organization which is prepared in such a way often decides for the next step which allows for self-improving even more efficiently, which in turn results in a quicker reaction to clients’ needs- the implementation of process-like attitude. The process-like attitude allows to identify weak elements of organization as well as help to improve them and identify those which should be included in an organization

The article characterises the properties of steam and special thermal oils as the basic heating media on motor ships. The features of the heating installations have been presented with the particular attention drawn to thermal oil installations in which exhaust gas heaters have been employed. Also an example of the comparative exergetic analysis has been included demonstrating the comparison between steam generation in exhaust gas boiler and oil heating system in the heater, assuming the identical heat flux transferred in the boiler and the heater from the exhaust gas to the heating medium (steam and thermal oil) and assuming identical increase of exhaust gas entropy in the heat exchangers under examination

Most of modern companies implement to the management principles known as “lean”. One of the methods proposed by Lean Management is a TPM (Total Productive Maintenance). There are applications of this method in relation to production systems. TPM can also be used to improve the quality of internal transport systems. The article presents the basic principles of TPM used in the method, as well as its use in stock products ready for distribution and in division of the car wipers

This article focuses on the sources of conflicts between a traffic maintenance department and production department which are very often unidentified by managers of an organization. These conflicts lead to the reduction of affectivity of an enterprise thus, the authors of this article tried to indicate all causes which result in an inappropriate cooperation between them. The identification of these problems and their analysis will let the organization take actions, which will improve the cooperation between two closely cooperating departments which, in turn will result in bigger effectiveness. The analysis of the problem was conducted in one of production company in Silesia voivodeship

This article is a trial to describe an author’s research method of measurement of an inside client’s satisfaction where in an enterprise, a inside client is production departments whose satisfaction with traffic maintenance staffs is to be assessed This method is based on a questionnaire survey which is conducted by means of two specialty prepared questionnaires. The first questionnaire refers to a production department’s satisfaction with actions taken by traffic maintenance staff and the second allows to assess the abilities of realizing tasks by traffic maintenance department in an organization. The obtained results, after analysing, allow to point out areas where repair actions should be taken or actions which are to improve the cooperation between analysed departments. This method is still at the stage of testing

The paper is characterized by efforts to create a business model of enterprise software and technical documentation. The author points out that the overriding factor is to identify actions to modeling, which defines the scope of the project. In mapping the organization and construction of scenarios of business processes is of paramount importance dictionary of phrases and descriptions of domain rules of correctness for the recording and processing. The author describes the key process models, partial (procedures) and elementary (the workflow map.) This indicates the suitability of BPMN and UML notation in the record of the mapping rules and modalities for the functioning of the organization and in the description of static and dynamic structure of the system. Pointing to the integration of business process management system architecture author assesses the suitability of the chosen modeling notation