Simulation modelling, performed by System Dynamics Modelling Approach and intensive use of computers, is one of the most convenient and most successful scientific methods of analysis of performance ...dynamics of nonlinear and very complex natural technical and organizational systems 1. The purpose of this work is to demonstrate the successful application of system dynamics simulation modelling at analyzing performance dynamics of a complex system of ship’s propulsion system. Gas turbine is a complex non-linear system, which needs to be systematically investigated as a unit consisting of a number of subsystems and elements, which are linked by cause-effect (UPV) feedback loops (KPD), both within the propulsion system and with the relevant surrounding. In this paper the authors will present an efficient application of scientific methods for the study of complex dynamic systems called qualitative and quantitative simulation System Dynamics Methodology. Gas turbine will be presented by a set of non-linear differential equations, after which mental-verbal structural models and flowcharts in System dynamics symbols will be produced, and the performance dynamics in load condition will be simulated in POWERSIM simulation language.
This paper deals with the application of System dynamics and Chaos theory in shipping using the example of freight rate forming. The development of new technologies, changes in structure and ...conditions, information accessibility, etc. are only some of the factors that intensify changes in freight rate forming in shipping. Therefore, shipping environment is becoming increasingly complex and dynamic. System dynamics seems to be a tool very suited for modelling of strategic and operational behaviour in shipping business. Due to the complex behaviour of these systems, chaos theory can also help in modelling of processes in shipping. The basic feature of chaotic systems is fine sensitivity in conditions at the beginning, when small change in input value may cause great changes in output values. By applying its concepts to the business process, as well as in freight rate forming in shipping, it prepares the business systems for quick response to the changes in the environment.
KEY WORDS: chaos theory, shipping, freight rate, system dynamics
By the development of global communication network, technological assumptions of better distance learning have been realized. Distance learning is not a new model of education introduced by Internet, ...since this concept has already been brought into many correspondence schools, in educational radio and TV broadcasts, in educational CD-s, i.e. in all types of learning in which teacher and student are mutually distant from each other. In order to make this model of distance learning successful, communication must be achieved between a teacher and a student. Great support to distance learning communication is provided by various video conference systems. Such systems enable physical distance of the user and represent very useful appendix to other distance learning tools. The article deals with Distance Learning Model, in the context of which distance learning courses would be organized, firstly for the students of the Faculty of Maritime Studies and additionally for all other concerned attendants. Actually, there is a dilemma regarding distance education and schooling and also model of providing teaching courses. Many questions have arisen in terms if this distance learning model is appropriate and effective, and consequently we tried to offer some answers regarding efficiency of the distance learning model.
The Marine Education Processes Frane Mitrovic; Ante Munitic
Journal of systemics, cybernetics and informatics,
08/2009, Letnik:
7, Številka:
4
Journal Article
Recenzirano
Odprti dostop
The paper deals with dynamic analysis of automatic ship steering gear systems utilising complex controls that function according to the principle of proportional, integral and derivation regulators. ...The analysis involves a system dynamic simulation modelling methodology as one of the most suitable and effective means of dynamic modelling of complex non- linear, natural, organisational and technical systems. The paper discusses system dynamics simulation models being used in qualitative (mental-verbal, structural) and quantitative (mathematical and computer) simulation models on ships equipped with trailing steering systems and PID regulator. Authors suggest using the presented models for designing and constructing new steering systems, for diagnosing existing constructions and for education in Universities.
Razvojem globalne komunikacijske mreže ostvarene su tehnološke pretpostavke za kvalitetnije obrazovanje na daljinu, što
nije novost koju donosi internetska tehnologija. S tim se pojmom susrećemo u ...različitim oblicima: u dopisnim školama, u
nastavnim radijskim i televizijskim emisijama, na nastavnim CD-romovima, to jest u svim onim oblicima učenja u kojima
su nastavnik i student međusobno prostorno udaljeni. Da bi postupak učenja na daljinu u funkciji razvoja menadžerskog
obrazovanja na pomorskim fakultetima bio uspješan, treba ostvariti komunikaciju između nastavnika i pomoraca. Veliku
podršku komunikaciji na daljinu danas pružaju raznovrsni videokonferencijski sustavi. Oni omogućuju sinkroniziranu
komunikaciju bez obzira na fizičku udaljenost korisnika i vrlo su koristan dodatak ostalim alatima za učenje na daljinu. U
ovom se radu izlaže model učenja na daljinu (Distance Learning) u okviru kojega bi se organizirali tečajevi na daljinu, prije
svega za studente i pomorce pomorskih fakulteta, ali i za sve ostale zainteresirane polaznike. Postoje dileme o izobrazbi
na daljinu kao o djelotvornom načinu davanja poduka u učenju. Pritom ima puno pitanja u vezi s tim koliko je učenje na
daljinu stvarno i uistinu učinkovito. Stoga su se ovdje pokušali dati o tome neki odgovori i moguća rješenja.
Quality level of inland waterway crew and inland waterways is closely related to traffic safety on these waterways. High quality inland crew, ships and inland waterways are important factors of ...safety and of minimizing losses. Damage to water transport occurs as a result of collisions, spills of oily water and low levels of protection at work. According to the statistics of the American Waterway Organization (AWO), most damage during voyage on inland waterways is caused by human error. The author analyzes the occurrence of accidents on inland waterways and their possible causes. In order to reduce the damage and the number of accidents, measures have been proposed in order to reduce the possibility of occurrence of human error by implementing safety management systems and increasing the quality of crews. PUBLICATION ABSTRACT
This paper shows the possibility of system dynamics implementation when hiring shipping capacity in a shipping company. Three key variables will be put in relation to demonstrate how the system ...works: hiring shipping capacity directly through a shipping agent; shipping agents offer closing delay because there is not enough shipping capacity, accepting the offer with the expansion of ones own shipping capacity, hiring or buying other ships. Hiring exclusively through a shipping agent is in direct relation to the possibilities of the system expansion, which opens up the possibilities of market expansion, higher income and consequently higher net profit. Offer closing delay makes a significant link in the system because it raises the question of what is going to be gained, or lost, with the delay. The delay can mean that something is becoming incompetitive or unwanted on the market. Accepting the offer, with previous simulation of the employment optimization of the required shipping capacity, means companys business efficiency and represents it on the market as a reliable partner. The possibility of expanding by renting the shipping capacity will depend upon freight or financial possibilities as well as decisions regarding the capital investment in new ships. The model was tested in real conditions through the example of the shipping company Atlantska plovidba Inc. The programme capacity DYNAMO from 2004 is used to show the simulation results.
Razina kvalitete posade i unutarnjih plovnih putova je usko povezana sa sigurnosti prometa na njima. Kvaliteta posade, broda i unutarnjih plovnih putova bitan je čimbenik sigurnosti plovidbe i ...sprječavanja nastajanja šteta. Štete u vodnom prometu nastaju kao posljedica sudara, izlijevanja zauljenih voda i slabe razine zaštite na radu.
Prema statistikama Američke organizacije za unutarnje plovne putove (American Waterway Organisation-AWO), uzrok većine šteta nastalih u plovidbi unutarnjim plovnim putovima je ljudska nepažnja. U ovom radu autori analiziraju pojavu nezgoda na unutarnjim
plovnim putovima i njihove moguće uzroke. S ciljem smanjivanja šteta i broja nezgoda, predlažu se mjere smanjivanja mogućnosti pojave ljudske pogreške uvođenjem sustava upravljanja sigurnošću prilagođenog unutarnjoj plovidbi te podizanju kvalitete brodaraca.
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