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U okviru ove doktorske disertacije istražena je podrška procesu operativnog planiranja proizvodnje i upravljanja resursima u malim i srednjim preduzećima. Poseban fokus stavljen je na aktivnosti raspoređivanja i terminiranja, koji čine najkompleksnije planerske probleme na operativnom nivou. Mala i srednja preduzeća (MSP) predstavljaju dominantnu kategoriju preduzeća u Republici Srbiji, a i šire u zemljama Evropske unije (EU-28). MSP predstavljaju najučestaliju kategoriju i u proizvodnom sektoru Republike Srbije i EU. Proizvodnja prema porudžbini i željama kupaca i procesna organizacija proizvodnje predstavljaju najzastupljeniji oblik proizvodnje u MSP, a Job Shop problem raspoređivanja je sastavni deo procesa operativnog tj. kratkoročnog planiranja proizvodnje u ovoj vrsti preduzeća. Imajući u vidu da operativno planiranje neposredno prethodi aktivnostima transformacije predmeta rada i stvaranju dodatne vrednosti, poseban naglasak dat je na upravljanju proizvodnim resursima u procesu proizvodnje (sirovine, materijali i drugi predmeti rada, mašine, alati i ostala sredstva za rad, ljudski resursi, vreme prema kome se aktivnosti planiranja realizuju, novac tj. kapital, informacije, tržište). U disertaciji se daje pregled osnovnih teorijskih pojmova: mala i srednja preduzeća, podrška MSP, proces upravljanja u MSP, planiranje proizvodnje i upravljanje resursima. Pored toga, posebno je definisan proces operativnog planiranja proizvodnje, sa aspekta aktivnosti iz kojih se sastoji. Raspoređivanje i terminiranje u proizvodnji su prepoznati kao jedni od najčešćih problema iz domena operativnog planiranja proizvodnje. Oni podrazumevaju raspoređivanje proizvoda na mašine, tj. pronalaženje redosleda radnih zadataka ili poslova koji treba da se izvrše na svakoj od više mašina. Pored toga obuhvataju i definisanje vremenskih termina za početak i završetak pojedinih proizvodnih aktivnosti. Cilj pravljenja adekvatnog rasporeda, tj. redosleda operacija, proizilazi iz ograničenja kapa, This dissertation proposal explores the support for operational production planning in small and medium-sized enterprises (SME). Special emphasis is put on scheduling activities that represent the most complex planning problem at the operational level. SMEs are the predominant category of enterprises both in Serbia and in the European Union (EU-28). SMEs also present the most frequent type of enterprises in the manufacturing sector in Serbia and the EU-28 countries. Make-to- Order (MTO) production and production organization according to the process are the most common forms of production in small and medium-sized manufacturing enterprises, and the Job Shop scheduling problem is an integral part of operational, i.e. short-term production planning in this group of enterprises. Bearing in mind that operational production planning is directly and closely related to the transformation of raw materials and semi-manufactured goods, which creates and adds value, we emphasize the need to manage manufacturing resources adequately in the production process (materials, machines, tools, labour force, time, money - i.e. capital, information, market). The dissertation proposal presents the overview of basic theoretical concepts: small and medium-sized enterprises, support for SMEs, the process of management in SMEs, production planning, and resource management. Additionally, the process of operational production planning is defined from the aspect of activities it encompasses. Production scheduling problems are observed as one of the most frequent issues in the field of operational production planning. They include scheduling products to machines, i.e. finding the sequence of tasks and activities that need to be performed on each of available machines. Also, it includes determination of time slots for the beginning and completion of certain manufacturing activities. The aim of an adequate schedule, i.e. sequence of operations, arises from the capacity constraints of production re

Mere značajnosti (Importance measures) predstavlјaju načine merenja, tj. brojčanog iskazivanja značajnosti pojedinih komponenata u sistemu sa aspekta ukupne pouzdanosti sistema. Merama značajnosti je moguće odrediti (izdvojiti) komponente najznačajnije za pouzdanost sistema. Od šezdesetih godina, kada je koncept mera značajnosti prvi put uveden, do danas postoji neprekidno interesovanje za ovu oblast, tako da se, pored primene tradicionalnih mera značajnosti, neprestano uvode i definišu nove mere radi njihove primene na specifične sisteme. Opšti nedostatak mera značajnosti, nezavisno od kategorije kojoj pripadaju, je taj što se one utvrđuju za svaku pojedinačnu komponentu, a tek nakon toga se može izdvojiti skup najznačajnijih komponenata zadate kardinalnosti..., Importance measures are numerical representations of the importance of each system’s component considering total system reliability. Using importance measures, the most important components for system reliability can be determined. Since the sixties, when the concept of importance measures was first introduced, there is a constant interest in this area, so that, in addition to the traditional importance measures, new measures for specific systems observed are continually introduced and defined. The general weak point of importance measures, irrespective of the category they belong to, is that they are determined for each individual component, and only afterwards a certain number of most important components can be set aside...

Importance measures are used for indexing system components due to their impact on the system's overall reliability. In order to identify the specific number of the most critical components, first-ranked components are singled out as the most important ones. However, importance measures consider only the influence of individual components and they are not applicable to combinations or groups of components. This common feature of importance measures is referred to in literature as one of still open issues. This paper proposes a new approach for determining the most important system components, where a whole set of components are determined simultaneously taking into account their interdependence. In systems with a large number of interdependent components, the number of the most important components which should be prevented is often limited due to the available budget. Using pre-known minimal cut sets, a mathematical model based on the Budgeted Maximum Coverage Problem is proposed. By its optimization, the simultaneous determination of all of the most important components whose total expenses do not exceed the limited overall budget is achieved. The new approach was tested by a series of experiments conducted over a set of test examples. The results of the experiments were compared with the results obtained using two commonly used cost importance measures.

U ovom radu je ispitan uticaj sklonosti ka riziku kao osobine ličnosti učesnika u lancu snabdevanja na troškove skladištenja i troškove usled nezadovoljene tražnje. Učesnici su na osnovu rezultata testa podeljeni na sklone i nesklone riziku. Formirana su dva tima koja su simulirala pivsku igru. Pokazano je da postoje razlike u troškovima između ova dva tima., This paper examines the causes of risk preferences, as one of the personality traits, of the participants in the supply chain on inventory and backorder costs. Based on test results the participants are divided into two groups: risk - seeking and risk - averse. Two teams are formed who simulated a beer game. It is shown that there are differences in costs between these teams.

A new approach to determination of the most critical multi-state components in multi-state systems is presented. The approach is based on solving an appropriate reliability optimization problem. The consideration is restricted on coherent and homogenous systems. Multi-state components may have different and distinct states which vary from complete failure to perfect functionality. The number of possible states is fixed and the same for all components and the system as a whole. The states correspond to different performance levels of components and the system. It is supposed that for each component state the corresponding probability and cost is known and that a higher state implies a higher cost. Further on, it is supposed that states of components are mutual statistically independent random variables. An original mathematical model for reliability calculation is developed and a corresponding optimization problem for identifying the most critical components is formulated and solved on numerical example.

S obzirom na brojne i značajne tehnološke promene koje karakterišu savremeno poslovanje, postalo je neophodno da se unapređuje i poslovna komunikacija. Da bi se unapredila poslovna komunikacija, između ostalih referentnih inovacija, organizuju se kontakt centri. Organizacija kontakt centra ima ključnu ulogu u obezbeđivanju njegove produktivnosti i efikasnosti, jer na osnovu nje klijenti i potencijalni klijenti ocenjuju ne samo rad kontakt centra, nego i rad banke, kao i njenih usluga i proizvoda. Da bi se izvršila optimizacija rada kontakt centra, potrebno je da se identifikuju sledeće promenljive i pojave: tip kontakt centra, tehnologija, kanali komunikacije, zaposleni i njihova obuka, zatim, potrebno je da se odredi potreban broj zaposlenih, ali i da se zaposleni pravilno rasporede po smenama, kao i da se prati njihov rad. Stavljanjem u optimalnu korelaciju navedenog, utiče se na poboljšanje poslovne komunikacije. Početkom pedesetih godina prošlog veka počeli su da se formiraju prvi kontakt centri i do danas bilo je dosta transformacija koje su uticale i na poslovnu komunikaciju. Poslovna komunikacija na više načina može da se unapređuje različitom organizacijom kontakt centara., Many significant tehnological changes describe modern business. It is necessary to improve business communication with the help of referential innovation i.e. contact centers. The contact center has an important role in securing productivity and effectiveness because clients and potential client evaluate the contact center, bank`s work services and products. In order to optimize the contact center`s work, certain variables must be identified e.g. the type of contact center, technology, channels of communication, employees and their training, the number of employees, shift working, supervision over employees. All of the issues mentioned above have great influence on business communication. In the early fifties of the last century began to form the first contact centers, and there have been a lot of transformations that have affected to the business communication. Business communication in many ways can promote contact centers with different organization.

Social sciences / Operations research, Predmet istraţivanja ove doktorske disertacije je pristup za detekciju i analizu grešaka u dinamiĉkim diskretnim spredšit modelima upravljanja zalihama, zasnovan na karakteristikama problema i naĉinu modeliranja. Postojeći pristupi za obezbeĊenje kvaliteta spredšit modela pokazali su se kao perspektivni, ali su nedovoljno ispitani i prilagoĊeni konkretnim problemima. Spredšit modeli korišćeni za evaluaciju ovih pristupa su najĉešće namenski kreirani, nisu realni primeri, relativno su mali i nisu prilagoĊeni kompleksnim problemima sa velikim brojem zavisnosti, tako da njihova primena u realnim okolnostima, kao i skalabilnost nisu potvrĊeni. Ovi pristupi, u najvećem broju sluĉajeva, zasnovani su na osobinama spredšit aplikacija, ali i idejama iz razliĉitih oblasti kao što su: softversko inţenjerstvo, operaciona istraţivanja i druge. Postojeći pristupi ne uzimaju u obzir karakteristike problema i naĉin modeliranja, koji znaĉajno utiĉu na nastanak, ali i mogućnost otkrivanja grešaka. Oni podrazumevaju da su izlazne vrednosti modela unapred poznate ili da korisnik moţe da obezbedi sve informacije o strukturi i ograniĉenima modela, što veoma ĉesto nije moguće. U skladu sa navedenim, opravdan je i neophodan razvoj novog pristupa, koji bi omogućio unapreĊenje kvaliteta spredšit modela za upravljanja zalihama, odnosno detekciju i analizu grešaka u njima. Osnovni cilj ove disertacije je kreiranje novog pristupa za obezbeĊenje višeg kvaliteta dinamiĉkih diskretnih modela upravljaĉkih problema operacionog menadţmenta, konkretno upravljanja zalihama, razvijenih u spredšitovima, razvojem algoritma za detekciju i analizu grešaka u navedenim modelima i utvrĊivanje njihovih uzroka na brz i efikasan naĉin., The subject of this doctoral thesis refers to error detection and debugging approach for dynamic discrete spreadsheet models of inventory control problems, based on problem characteristics and modelling method. Existing quality assurance approaches are very perspective, but insufficiently tested and adapted to actual problems. Spreadsheet models used for evaluation of those approaches are usually created just in that purpose and aren’t real practical examples. Experimental spreadsheet models are generally small and aren’t adjusted to complex problems with many dependencies. Applicability and scalability of existing quality assurance approaches has not been proven in wider context. In most cases, approaches are based on spreadsheet application characteristics and ideas from different scientific areas, such as: software engineering, operations reaserch and others. Existing approaches do not consider problem characteristics and modelling method, which significantly influence error occurrence and error detection. Those approaches consider that model output values are known in advance or that all informations about model structure and constraints are provided by user. Very often, both presumptions are unacceptable for models used in practice. In accordance with aforementioned, development of new improved quality assurance approach for inventory control spreadsheet models is justified and necessary. Main goal of this dissertation is to create new spreadsheet quality assurance approach for dynamic discrete models of operations management problems, specifically inventory control problems, developed in spreadsheets, by developing algorithm for error detection and quick and efficient debugging for mentioned models. Newly developed error detection and debugging approach for dynamic discrete spreadsheet models of inventory control problems, presented in this dissertation, is adapted to users and allows quality improvement of inventory control spreadsheet models.

Predmet istraživanja ovog rada predstavlja razvoj rešenja realnog problema pomoću grafovskih baza podataka. Ukratko su opisani osnovni koncepti grafovskih baza podataka. Ono što ovaj tip baza izdvaja, u odnosu na ostale NoSQL baze podataka, je osobina da podatke i veze među njima smatra ravnopravnim. Takođe, njihov način skladištenja podataka je najpribližniji ljudskom razmišljanju što ih čini veoma intuitivnim. U centralnom delu rada je dat predlog za otkrivanje pravara u kasko osiguranju korišćenjem Neo4j grafovske baze za skladištenje podataka. Pomenuti tip baza podataka za dati problem nudi jednostavno rešenje i bolje rezultate prostim prolaskom kroz graf., The main subject of this paper is the development of the solution to the real problem, using graph database. Elementary concepts of the graph databases are briefly explained. Unlike the other NoSQL databases, Graph database treats data and connections between data equally. Also, the way they store data is closest to human thinking, which makes them very intuitive. Central part of the paper presents the solution for the detection of frauds in car insurance by using Neo4j graph database for storing data. Graph database offers a simple solution and better results for this problem by simply going through the graph.

Zavisno od raspolozivosti resursa i nivoa razvoja, svaka zemlja je specijalizovana u određenim delatnostima. Tokom razvoja, zemlje sprovode sektorsku transformaciju. U cilju da postignu viši nivo ekonomskog razvoja, neophodno je da svaka zemlja diversifikuje ekonomske aktivnosti i odredi u koje ekonomske aktivnosti treba ulagati. Cilj ovog rada je da analizira efekte ekonomske strukture i diversifikaciju aktivnosti na razvoj Srbije u period 2007- 2012.godine. Model optimizacije je korišćen da se pokaže diversifikacija aktivnosti. Nadalje, granica efikasnosti je korišćena da se pokažu prinosi, rizici i korelacija između aktivnosti. Rezultati pokazuju da ekonomske aktivnosti Rudarstvo, Državna uprava i obavezno socijalno osiguranje, Ostale uslužne delatnosti, Finansijske delatnosti i delatnosti osiguranja, Umestnost, zabava i rekreacija treba da budu pokretači ekonomskog rasta, zato što obezbeđuju balans između rasta i sigurnosti prema GVA u ekonomskim aktivnostima., Each economy specializes in certain economic activities depending on the development level and availability of resources. During their development, countries undergo sectoral transformation. In order to achieve a higher level of economic development, it is necessary for a country to diversify its economic activities and determine which economic activities should be invested in. The aim of this paper is to analyse the effects of economic structure and diversification activities on the development of Serbia for the period 2007-2012. Optimization model has been used to present diversification of activities. Furthermore, the efficiency frontier is used to show returns, risks and correlation among activities. The results show that the economic activities - Mining and quarrying, Public administration and defence, Compulsory social security, Other service activities, Financial and insurance activities, Arts, entertainment and recreation should be drivers of economic growth, because they provide a balance between growth and security regarding GVA in economic activities.

In the context of growing concern over the global environment and related sustainability issues, the purpose of this research is to stimulate discussion about the Environmental Performance Index (EPI) and its necessary role not only in measuring postgraduate students' attitudes about EPI, and its nine categories underpinned, but also, their important role in the development of appropriate curriculum of programs that are about environmental management and sustainable development as well. Further on, the obtained results of the presented research in the paper broaden the understanding of the opportunities for not only the Republic of Serbia but every country as well, in using the EPI methodology as it has a wide applicability in improving environmental pillars of their future sustainability.

Having in mind the immense value of the Danube River and knowing that risk assessment of its pollution is one of the key elements for ecology and the health of people in its region, in this paper we emphasized the importance of risk assessment of ship-generated wastewater - particularly in the case of greywater discharges. Although, a number of methods for measuring and analysing different environmental risks have been developed, previous research shows that the failure mode and effect analysis (FMEA) method is applicable in solving environmental issues. Therefore, we conducted our research with the main purpose to develop a model of FMEA method application for assessing the risks of ship-generated greywater discharges based on estimated data for total quantity of greywater, the size of the exposed population to the pollution of greywater and the possibilities of this pollution detection. Risk analysis was performed on official data for nine ports on the Danube River on inland waterways of the Republic of Serbia. Based on the obtained results, we concluded that measures, recommendations and risk prevention strategies for ship-generated greywater discharges should go into two major directions: (1) decreasing the pollution caused by greywater discharges; (2) increasing the number of water quality monitoring stations.

Управљање ланцем снабдевања обухвата планирање свих активности које се односе на снабдевање, као и координацију и колаборацију са партнерима у ланцу. Услед недовољне координације, долази до појаве ефекта бича. Узроци ефекта бича у ланцима снабдевања могу бити операциони и бихејвијорални., Supply chain management encompasses the planning of all activities related to supply, including coordination and collaboration with partners in the chain. Lack of coordination can cause the bullwhip effect. The causes of the bullwhip effect in supply chains can be operational and behavioral. The majority of authors tackle operational causes, while behavioral are mentioned as important but are insufficiently explored. Behavioral causes, among others, include personality traits. Although the literature emphasizes the necessity of collaboration between participants in the supply chain so as to reduce the bullwhip effect, no research has been done on the effect of cooperation as a personality trait. This dissertation analyzes the impact of cooperativity of participants in a supply chain on chain costs through the implementation of a customized beer game and shows how to form a supply chain with cooperative participants. Cooperativity of participants was examined using a questionnaire in social value orientation. The general hypothesis of the dissertation was confirmed – the increase in cooperativity of participants in the supply chain can contribute to the improvement of the functioning of the chain and solving complex problems of coordination. The study of the behavioral phenomenon in the supply chain and the analysis of communication and interaction between participants in the supply chain used transactional analysis and showed how to improve the cooperativity of the participants in the formed supply chain. At the end, the behaviors of cooperative participants which gave good results were defined as the rules of conduct in the supply chain and were included in the simulation by applying Petri nets. This proved that Petri nets allow for the possibility of including a number of factors which influence the supply chains, even factors such as personality traits; therefore, the simulation by applying Petri nets can replace the real experiment.

Context: Liraglutide is a glucagon-like peptide-1 analog and glucose-lowering agent whose effects on cardiovascular risk markers have not been fully elucidated. Objective: We evaluated the effect of liraglutide on markers of oxidative stress, heme oxygenase-1 (HO-1), and plasma ghrelin levels in patients with type-2 diabetes mellitus (T2DM). Design and Setting: A prospective pilot study of 2 months duration has been performed at the Unit of Diabetes and Cardiovascular Prevention at University of Palermo, Italy. Patients and Intervention(s): Twenty subjects with T2DM (10 men and 10 women; meanage: 57 +/- 13 y) were treated with liraglutide sc (0.6 mg/d for 2 wk, followed by 1.2 mg/d) in addition to metformin (1500 mg/d orally) for 2 months. Patients with liver disorders or renal failure were excluded. Main Outcome Measure(s): Plasma ghrelin concentrations, oxidative stress markers, and heat-shock proteins, including HO-1 were assessed. Results: The addition of liraglutide resulted in a significant decrease in glycated hemoglobin (HbA1c) (8.5 +/- 0.4 vs 7.5 +/- 0.4%, P LT .0001). In addition, plasma ghrelin and glutathione concentrations increased (8.2 +/- 4.1 vs 13.6 +/- 7.3 pg/ml, P = .0007 and 0.36 +/- 0.06 vs 0.44 +/- 0.07 nmol/ml, P = .0002, respectively), whereas serum lipid hydroperoxides and HO-1 decreased (0.11 +/- 0.05 vs 0.04 +/- 0.07 pg/ml, P = .0487 and 7.7 +/- 7.7 vs 3.6 +/- 1.8 pg/ml, P = .0445, respectively). These changes were not correlated with changes in fasting glycemia or HbA1c. Conclusions: In a 2-months prospective pilot study, the addition of liraglutide to metformin resulted in improvement in oxidative stress as well as plasma ghrelin and HO-1 concentrations in patients with T2DM. These findings seemed to be independent of the known effects of liraglutide on glucose metabolism.

MOSFET electronic components are already the subject of several decades of research in various fields of dosimetry and radiation protection. Special interest appeared when these components are started to be used as dosimeters in radiotherapy with electron beams. However, if one looks much more serious in the wider scientific research horizon, all the results obtained in experiments with precisely defined energies of incident electrons can be used in other disciplines which consider the impacts spectra of cosmic radiation on electronic devices, which is especially importance for cosmic science and space research instrumentation. In this paper, one of the objectives was to examine the electrical characteristics specially designed ESAPMOS RADFET dosimeters in the experiments that were conducted on a linear accelerator installations. RADFET components are bombarded electron beams energy of 6 MeV and 8 MeV, and then are followed by changes in threshold voltage shift mean values depending on the change of absorbed dose is referred to as D(cGy) was determined in water. Conclusions performance RADFET components are more than encouraging in terms of further research to improve the linearity of the energy dependence as widely energy electrons. In the second part of the test complex structure of packaging components RADFET focus is placed on the determination of the energy deposited in layers that are of interest for the analysis of microscopic processes related to the recombination of radiation-induced electron-hole pairs. Transport incident electrons through all the layers of structure RADFET component type ESAPMOS was carried out numerical simulations of the Monte Carlo method using the software package FOTELP-2K12. On this occasion, were taken into account all the physical processes of interaction of electrons with materials given structure. When he conquered the numerical application of mathematical and physical model for determining the value of the absorbed energy as th

Predmet ovog rada je ljudska greška kao uzrok otkaza tehničkih i organizacionih sistema. U analizi rizika, kao obaveznom delu savremenog upravljanja projektima i procesima, se sve veća pažnja poklanja upravo proučavanju pouzdanosti čoveka i ljudskoj grešci. Ljudska greška se posmatra kao svako delovanje van tolerancije ili odstupanje od norme, pri čemu je nivo prihvatljivosti unapred, formalno ili neformalno, definisan sistemom. Pored prikaza različitih pristupa za analizu ljudske greške, detaljno će biti predstavljena metoda 'Analiza i sistem klasifikacije ljudskih grešaka' (Human Factors Analysis and Classification System - HFACS). Ova, relativno nova, metoda za analizu uzroka ljudskih grešaka biće ilustrovana konkretnom primenom na primeru iz prakse., The subject of this paper is human error as cause of technical and organizational system failure. The risk analysis, as important part of the modern project and processes management, focus increasing attention to the study of human reliability and human error. Human error is considered as any activity outside the tolerance limits which are predefined by the system, formally or informally. Besides a review of different approaches and methods for human errors analysis, the Human Factors Analysis and Classification System (HFACS) method will be presented in detail. This relatively new method for the analysis of human errors causes will be illustrated using a real life example.

In a world with growing energy demand and increasing energy scarcity, the need for new methods of risk analysis of energy supplies has been emphasized. These methods became even more important for specific energy resources whose future usage is quite questionable, such as oil. This paper will try to examine potential use of one such method for measuring energy security of countries and its dependency on external sources. One method used is failure mode and effect analysis (FMEA), widely used in risk analysis and an inductive modelling approach used to evaluate potential failure modes and their causes. The main goal of FMEA is to prioritize potential risks and lead to actions that will eliminate or reduce the likelihood or effects of their occurrence. Risk evaluation and priority risk numbers were assessed based on expert opinion, using specially created scales developed for the monitored problem. In this paper we try to implement FMEA as a method for quantifying risk of oil shortage for European Union countries and their ability to respond to their growing oil demand and dependency. As a result of this study, ranking these countries by the level of risk they are exposed to will be presented, as well as analysis of the reasons underpinning such rankings.

Koncept prevencije je sve značajniji u savremenoj medicini. Da bi prevencija bila efektivna i efikasna, neophodno je poznavati zdravstvene faktore rizika određene bolesti kao i kako oni utiču na rizik od oboljevanja. U ovom radu će biti prikazano kako se Petrijeve mreže mogu primeniti u proceni rizika od dobijanja kardiovaskularne bolesti. Osnova za procenu rizika je bila Framinghamska studija, koja se bavi indentifikacijom i prevencijom rizika dobijanja koronarnih bolesti. Koristeći rezultate studije, formulisana je obojena Petrijeva mreža kojom se modeliraju zdravstveni faktori rizika i simulira proces procene rizika da posmatrani pacijent oboli od kardiovaskularne bolesti u budućnosti. Pored procene trenutnog stanja pacijenta, cilj je i da se, promenom različitih vrednosti promenljivih zdravstvenih faktora, simuliraju različiti životni scenariji koji mogu dovesti do smanjenja rizika od oboljevanja. Za modeliranje i simulaciju korišćen je softver CPN Tools., The concept of prevention is becoming more and more important in modern medicine. In order for prevention to be effective and efficient, is necessary to know the health risk factors of the particular disease and how they can have influence on the disease itself. In this paper it will be shown how Petri nets can be applied in assessing the risk of getting cardiovascular disease. The basis for the assessment of risk was the Framingham heart study, which deals with the identification of and prevention of risk of getting coronary heart disease. Using the results of the study, a colored Petri net has been formulated, which can be used for modeling health risk factors and simulating the process of assessing the risk from getting a cardiovascular disease that a given patient could be suffering in the future. In addition to the assessment of the current condition of the patient, and the aim is that, by changing the values of variables of different health factors, simulate different life scenarios that can lead to a reduction in the risk of disease. For modeling and simulation software CPN Tools has been used.

Purpose - The purpose of this paper is to develop a methodology for automatically determining the optimal allocation of police officers in accordance with the division and organization of labor. Design/methodology/approach - The problem is defined as the problem of the goal programming for which the mathematical model of mixed integer programming was developed. In modeling of the scheduling problem the approach police officer/scheme, based on predefined scheduling patterns, was used. The approach is applied to real data of a police station in Bosnia and Herzegovina. Findings - This study indicates that the determination of monthly scheduling policemen is complex and challenging problem, which is usually performed without the aid of software (self-rostering), and that it can be significantly facilitated by the introduction of scheduling optimization approach. Research limitations/implications - The developed mathematical model, in its current form, can directly be applied only to the scheduling of police officers at police stations which have the same or a similar organization of work. Practical implications - Optimization of scheduling significantly reduces the time to obtain a monthly schedule. In addition, it allows the police stations to experiment with different forms of organization work of police officers and to obtain an optimal schedule for each of them in a short time. Originality/value - The problem of optimal scheduling of employees is often resolved in other fields. To the authors knowledge, this is the first time that the approach of goal programming is applied in the field of policing.

Upravljanje lancem snabdevanja obuhvata planiranje svih aktivnosti koje se odnose na snabdevanje, kao i koordinaciju i kolaboraciju sa partnerima u lancu. Usled nedovoljne koordinacije, dolazi do pojave efekta biča. Uzroci efekta biča u lancima snabdevanja mogu biti operacioni i bihejvijoralni., Supply chain management encompasses the planning of all activities related to supply, including coordination and collaboration with partners in the chain. Lack of coordination can cause the bullwhip effect. The causes of the bullwhip effect in supply chains can be operational and behavioral. The majority of authors tackle operational causes, while behavioral are mentioned as important but are insufficiently explored. Behavioral causes, among others, include personality traits. Although the literature emphasizes the necessity of collaboration between participants in the supply chain so as to reduce the bullwhip effect, no research has been done on the effect of cooperation as a personality trait. This dissertation analyzes the impact of cooperativity of participants in a supply chain on chain costs through the implementation of a customized beer game and shows how to form a supply chain with cooperative participants. Cooperativity of participants was examined using a questionnaire in social value orientation. The general hypothesis of the dissertation was confirmed – the increase in cooperativity of participants in the supply chain can contribute to the improvement of the functioning of the chain and solving complex problems of coordination. The study of the behavioral phenomenon in the supply chain and the analysis of communication and interaction between participants in the supply chain used transactional analysis and showed how to improve the cooperativity of the participants in the formed supply chain. At the end, the behaviors of cooperative participants which gave good results were defined as the rules of conduct in the supply chain and were included in the simulation by applying Petri nets. This proved that Petri nets allow for the possibility of including a number of factors which influence the supply chains, even factors such as personality traits; therefore, the simulation by applying Petri nets can replace the real experiment.

Here we report identification of the lkh1 gene encoding a LAMMER kinase homolog (Lkh1) from a screen for DNA repair-deficient mutants in Ustilago maydis. The mutant allele isolated results from a mutation at glutamine codon 488 to a stop codon that would be predicted to lead to truncation of the carboxyterminal kinase domain of the protein. This mutant (lkh1(Q488*)) is highly sensitive to ultraviolet light, methyl methanesulfonate, and hydroxyurea. In contrast, a null mutant (lkh1 Delta) deleted of the entire lkh1 gene has a less severe phenotype. No epistasis was observed when an lkh1(Q488*) rad51 Delta double mutant was tested for genotoxin sensitivity. However, overexpressing the gene for Rad51, its regulator Brh2, or the Brh2 regulator Dss1 partially restored genotoxin resistance of the lkh1 Delta and lkh1(Q488*) mutants. Deletion of lkh1 in a chk1 Delta mutant enabled these double mutant cells to continue to cycle when challenged with hydroxyurea. lkh1 Delta and lkh1(Q488*) mutants were able to complete the meiotic process but exhibited reduced heteroallelic recombination and aberrant chromosome segregation. The observations suggest that Lkh1 serves in some aspect of cell cycle regulation after DNA damage or replication stress and that it also contributes to proper chromosome segregation in meiosis.

MicroRNAs (miRNAs) belong to the class of small non-coding RNAs which have important roles throughout development as well as in plant response to diverse environmental stresses. Some of plant miRNAs are essential for regulation and maintenance of nutritive homeostasis when nutrients are in excess or shortage comparing to optimal concentration for certain plant species. Better understanding of miRNAs functions implies development of efficient technology for profiling their gene expression. We set out to establish validate the methodology for miRNA gene expression analysis in cucumber grown under suboptimal mineral nutrient regimes, including iron deficiency. Reverse transcription by "stem-loop" primers in combination with Real time PCR method is one of potential approaches for quantification of miRNA gene expression. In this paper we presented a method for "stem loop" primer design specific for miR398, as well as reaction optimization and determination of Real time PCR efficiency. Proving the accuracy of this method was imperative as "stem loop" RT which consider separate transcription of target and endogenous control. The method was verified by comparison of the obtained data with results of miR398 expression achieved using a commercial kit based on simultaneous conversion of all RNAs in cDNAs.

In humans uric acid (UA) is the end product of degradation of purines. The handling of UA by the renal system is a complex process which is not fully understood. To date, several urate transporters in the renal proximal tubule have been identified. Among them, urate transporter 1 (URAT1) and a glucose transporter 9 (GLUT9) are considered of greater importance, as potential targets for treatment of hyperuricemia and the potential associated cardio-metabolic risk. Therefore, the recognition of the metabolic pathway of UA and elucidation of occurrence of hyperuricemia may provide important insights about the relationship between UA, pre-hypertension (preHT) and the metabolic syndrome (MetS). We also review the available clinical studies in this field, including experimental studies dealing with the mechanisms of UA transport via different transporters, as well as current treatment options for hyperuricemia in patients with MetS, preHT or cardiovascular risk factors.

Resistin is an adipocyte-and monocyte-derived cytokine which has been implicated in the modulation of insulin action, energy, glucose and lipid homeostasis. Resistin has been associated with insulin resistance and many of its known complications. As a molecular link between metabolic signals, inflammation, and vascular dysfunction, resistin can be proposed as playing a significant role in the heightened inflammatory state induced by metabolic stress linked to excessive caloric intake, thus contributing to the risk for metabolic syndrome (MetS), type 2 diabetes (T2DM), and cardiovascular diseases (CVD). In this review, we highlighted the role of resistin, as an inflammatory cytokine, in the development of CVD, T2DM and the MetS.

Differences in the level of economic achievement in different countries are determined by the availability of resources and economic policies. Economic development could be influenced by the structure of economic activities. The paper brings the analysis of Serbian economic activities structure and its influence on the level of development during the period 2008-2011. The optimization model has been used to show economic activities to be invested in in order to achieve development. The results show that the most important economic activities in enhancing development are information and communication; finance and insurance; water supply, sewerage, waste management and remediation activities.

This paper observe multi-period multi-product production planning problem in make-to-stock production environment with limited production capacity. Such problem is identified in Fast Moving Consumer Goods industry. The goal was to develop an algorithm for supporting dynamic production triggering decisions in relation with two supply chain key performance indicators: stock cover and customer service level. The presented approach is applied to a real example in several scenarios based on different decision criteria.