Verification of business process workflows

Modeling of Business processes is essential in many areas. Workflows represent the Business processes. It is possible to identify potential problems while performing verification of workflows. One of the objectives of the verification is to assure reachability. This includes analysis of the deadlock and tempo blocking freeness properties. The paper presents verification approach based on using an adjacency matrix. Spreadsheets are used as a verification tool. The approach is illustrated by the examples which justify the importance of verification in workflow processes

Knowledge based traffic signal control model for signalized intersection

Intelligent transportation systems have received increasing attention in academy and industry. Being able to handle uncertainties and complexity, expert systems are applied in vast areas of real life including intelligent transportation systems. This paper presents a traffic signal control method based on expert knowledge for an isolated signalized intersection. The proposed method has the adaptive signal timing ability to adjust its signal timing in response to changing traffic conditions. Based on the traffic conditions, the system determines to extend or terminate the current green signal group. Using the information from its traffic detectors of isolated intersection, the proposed controller gives optimal signals to adapt the phase lengths to the traffic conditions. A comparative analysis between proposed control algorithm, fuzzy logic (FLC) and fixed-timed (pre-timed) controllers has been made in traffic flows control, with varying traffic volume levels, by using simulation software ‘Arena’. Simulation results show that the proposed traffic signal control method (EKC) has better performance over fuzzy logic and conventional pre-time controllers under light and heavy traffic conditions

On the “Modelling of business, industrial and transport systems” international conference

„On the “Modelling of business, industrial and transport systems” international conference" Ukio Technologinis ir Ekonominis Vystymas, 14(3), p. 244-246 First published online: 21 Oct 201

PLA‐based formalization of business rules and their analysis by means of knowledge‐based techniques / Pla metodu grįstas verslo taisyklių formalizavimas ir analizė taikant žiniomis grįstas metodikas

The paper presents an approach that applies the knowledge engineering techniques for representing and analysing business rules. These rules are represented by production rules using concepts of a state‐based piece‐linear aggregate (PLA) model. A knowledge base of the business rules is analysed by checking its consistency (static properties) and dynamic constraints (dynamic properties). The analysis is performed by applying methods for decision table verification and reachable state validation as well as supporting tools. The proposed approach is illustrated by an example of Userv insurance company services. Santrauka Straipsnyje pateikiamas būdas, kurio remiantis taikomos žiniomis grįstos metodikos verslo taisyklėms pavaizduoti ir analizuoti. Verslo taisyklės iliustruojamos produkcinėmis taisyklėmis, naudojant būsenomis grįsto atkarpomis tiesinių agregatų (PLA) modelio konceptus. Verslo taisyklių žinių bazė analizuojama tikrinant jos suderinamumą (statines savybes) ir dinaminius suvaržymus (dinamines savybes). Analizė atliekama taikant sprendimo lentelių verifikavimo ir pasiekiamų būsenų validavimo metodus bei šiuos metodus realizuojančias programines priemones. Siūlomas būdas iliustruojams Userv draudimo kompanijos paslaugų pavyzdžiu. First published online: 21 Oct 2010 Reikšminiai žodžiai: verslo taisyklės, PLA, žinių bazė, sprendimo lentelė, suderinamumo ir dinaminiai suvaržymai

An agricultural sector models for regional policy analysis and strategic planning

The integration of Lithuania into the European Union requires serious preparation, determining possible changes in agrarian sector and rural development and their consequences, ensuring the necessary information supply to finding and substantiation of rational strategic solutions. The paper analyzes trends of systematic analysis of the agrarian sector of the region, tools for the search of solutions, reveals the possibilities of modelling methods and information technologies application in determining the sustainable development strategy. The suggested methodic of integrated modelling of agricultural production processes in regional and farm level is introduced. The scheme of agrarian production system and some functional dependencies are presented. The problems that are expected to be solved in future are formulated. First Published Online: 14 Oct 201

Fuzzy traffic control for three-sided intersection

This paper presents fuzzy logic traffic controller for three- sided isolated intersection. This controller gets and computes data on real time then it makes decision what to do, extend or to terminate the current green phase it depends on vehicles demand. Two methods has been compared: fuzzy logic with fixed time (pretimed) method. In order to reaching the goal, traffic Simulation models were created to control intersection in both cases. Varying traffic volumes, delays and queue length has been compared after simulation. The simulation results shows, that controller based oil fuzzy logic works significantly better then pretimed and it reduce average delays and queues lengthKauno technologijos universitetasTaikomosios informatikos katedraVytauto Didžiojo universiteta

An Agricultural sector models for regional policy analysis and strategic planning

The integration of Lithuania into the European Union requires serious preparation, determining possible changes in agrarian sector and rural development and their consequences, ensuring the necessary information supply to finding and substantiation of rational strategic solutions. The paper analyzes trends of systematic analysis of the agrarian sector of the region, tools for the search of solutions, reveals the possibilities of modelling methods and information technologies application in determining the sustainable development strategy. The suggested methodic of integrated modelling of agricultural production processes in regional and farm level is introduced. The scheme of agrarian production system and some functional dependencies are presented. The problems that are expected to be solved in future are formulate

Copula effect on investment portfolio of an insurance company

For an insurance company, the planning has to be carried out under uncertainty. Thus, the decision making model includes the parameters that are not completely known at the current point of time, when the decision has to be taken. These parameters can be named as risk factors. The activity of insurance company is affected by many risk factors, thus the multivariate uncertainty space, where the correlations among these factors are possible, can be constructed. For their dependency structure, the alternative method – copula functions – are employed, which allows to model the non‐linear dependencies between the correlated stochastic variables. The purpose of this work is to explore the copula effect on the investment portfolio of the insurance company. The insurance business is influenced by a large number of stochastic parameters, and decisions concerning the assets that must be invested over time to cover liabilities and to achieve goals subject to various uncertainties and various constraints are considered. Two approaches of making decision models under uncertainty are applied in the integrated dynamic management of insurance company's financial assets and liabilities. One of them allows to evaluate the company's strategy and technically is based on stochastic simulation. The other approach generates a strategy from the stochastic optimization model. Two copula functions – Gaussian copula and Student's t‐copula – concerning the investment performance are employed while generating the set of scenarios for representing the behaviour of risk factors in the multivariate structure. Junginių įtakos draudimo kompanijos investiciniam portfeliui tyrimas Santrauka. Sprendimai, susiję su ilgalaikiu draudimo kompanijos veiklos planavimu, yra dažniausiai veikiamiaplinkos neapibrėžtumų, todėl dalis ar visi modelio parametrai nėra iki galo žinomi tuo momentu, kai sprendimai turi būti priimti. Šie parametrai dar vadinami rizikos veiksniais. Kadangi draudimo kompanijos veiklai įtaką daro tam tikra rizikos faktorių aibė, tai formuojama daugiamatė neapibrėžties erdvė su galimomis priklausomybėms tarp šios erdvės kintamųjų – rizikos veiksnių. Jų priklausomybei modeliuoti taikoma alternatyvi metodika – junginiai: tai funkcijos, leidžiančios aprašyti netiesines priklausomybes tarp stochastinių kintamųjų, nebūtinai pasiskirsčiusių pagal normalųjį dėsnį. Šio darbo tikslas – ištirti junginių įtaką draudimo kompanijos sprendimams, susijusiems su ilgalaikiu investicinės veiklos planavimu. Tokio tipo uždaviniuose egzistuoja gan daug stochastinių parametrų, ir sprendimai turi būti parenkami taip, kad grąža iš investuojamo turto leistų padengti draudimo kompanijos įsipareigojimus laikui einant bei uždirbti kuo daugiau pelno. Tikslui pasiekti taikomos dvi skirtingos sprendimų priėmimo modeliavimo metodikos: tai imitacinis modeliavimas ir stochastinis programavimas (optimizavimas). Šios metodikos daugiausia skiriasi tuo, kaip parenkami sprendimai: stochastinis imitavimas remiasi efektyvaus rinkinio koncepcija, o taikant antrąjį metodą sprendimai gaunami iš daugelio tochastinio optimizavimo modelio etapų. Bendra savybė yra ta, kad stochastinis procesas, aprašantis investicinės veiklos rizikos faktorius, yra esminė įvestis į abu modelius ir yra apibrėžiamas sudarant scenarijų aibes. Eksperimento pavyzdyje taikomos dvi funkcijos – Gauso junginys ir Studento t2 junginys – šių rizikos veiksnių priklausomybėms aprašyti generuojant scenarijų aibes. Reikšminiai žodžiai: stochastinis imitavimas, stochastinis optimizavimas, scenarijų generavimas,sprendimų priėmimas, junginių funkcijos, investicinis portfelis, turto ir įsipareigojimų valdymas, draudimas. First published online: 21 Oct 201

Piece linear aggregates model for fuzzy traffic control

This paper presents a fuzzy logic controller formal specification for an isolated signalized intersection. The controller controls the traffic light timings to ensure smooth flow and avoid congestion. The formal language of the extended Piece Linear Aggregates (PLA) implements the fuzzy logic model. The PLA model was supplemented by two stages – the function for fuzzy sets which transform input data to fuzzy set and the rule base which is used to specify the current system situation depending on input data. An example of three – sided intersection system is given to illustrate the presented methoKauno technologijos universitetasTaikomosios informatikos katedraVytauto Didžiojo universiteta

An Agricultural Sector Models for Regional Policy Analysis and Strategic Planning

Santr. anglBibliogr.: p. 248 (20 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij