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Background: Blockchain project implementation in smart cities represents a novel challenge in information technologies. Lack of functional framework and guidelines impact these implementations and add additional uncertainty. Authors in their research on this subject seek to discover a functional framework to improve the implementation process. The research is divided into 3 parts: identification of best application areas, critical success factors, and implementation performance indicators. Purpose: The goal of this paper is to present findings on the performance indicators and offer additional insight into their nature as well as point to lesser-known performance indicators of blockchain projects. Study design/methodology/approach: Authors used the Delphi technique and according to the methodology, a panel of 33 experts was presented with a list of performance indicators and asked to add additional performance indicators as well as to assess their importance. The research foundation was based on the literature review which resulted in 9 performance indicators for the blockchain project implementation in smart cities. Findings/conclusions: The experts proposed 8 additional performance indicators; however, only 1 of them had required consensus to be accepted by the panel. This paper will disclose both groups of performance indicators and preserve them for further scientific discussion since the performance indicators that were proposed by the individual experts but did not reach panel consensus will not be contained in the further research results. After all rounds of the Delphi method were finished the experts concluded the list of the 5 most important performance indicators for the implementation of blockchain projects in the smart city. Limitations/future research: Due to limited resources and lack of experts, the size of the panel is limited to only 33 experts. In addition, smart cities are usually managed by the public sector, so access to all data is limited. The findings presented in the paper can be further used to improve the efficiency of blockchain projects.

The paper presents a comprehensive complex model for the Declaration of Conformity of the Excitation System. The necessary projects for conformity assessment, standardization, accreditation and metrology are given. Some testing and compliance modules are listed. A part of the test according to the CB scheme of Low-voltage switchgear and controlgear assemblies for the excitation system Tesla ES 7000A is presented, which is according to valid standards, and for nominal currents up to 7000 A. A part of the test according to the CB scheme of electromagnetic compatibility for the Tesla ES excitation regulator is presented. The Declaration of Conformity of the Tesla ES 1600 excitation system is presented.

Field winding temperature of the synchronous generator is one of limiting factors shaping generator PQ capability curve. Therefore of great operational importance is to have information about this temperature estimated with the utmost accuracy. It can be measured directly using built-in temperature sensors or determined indirectly. With the increasing penetration of renewable energy sources into the high-voltage transmission system, the fundamental changes happen in the way conventional generating units work, including hydrogenerators. They are facing the new operating modes characterized by rapid load changes and an increased number of start-stop cycles. These modes of operation lead to additional thermal stress of the hydrogenerator parts, including the rotor. In order to be able to respond to new demands that they are faced with, it is necessary to estimate the actual thermal capacity of the rotor and its influence on the dynamic hydrogenerator PQ capability curve.

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While in operation, the generators are exposed to various electrical, thermal, mechanical and chemical stresses, but also to pollutants that shorten their lifetime. All of these factors have detrimental impact on generator, especially to the characteristics of their insulation system. It should be kept in mind that the influence of these factors is interactive and simultaneous. Fast detection and fault repair are of great importance because they enable further exploitation of generator and reduce financial losses due to undelivered energy.

In the modern world there are lots of considerations about transportation in general, including analysis and decision making about the current situation and planning as well, that means preparation for future needs through defining policies, goals and investments to design transportation networks and facilities. The environmental consequences of general transportation and agriculture itself are of special interest as well. Transport activities are given and unavoidable in every society, for any country, but their intensive practice often produces negative effects on surroundings. The quoted problem emerges in a special manner when observing merged - as agricultural transportation: modeling ecological issues here is particularly complex due to great number of variables and random elements dependent on subjectivity in decision making, appearance of unexpected events and often incorrect data. In this paper authors discuss different aspects of agricultural transportation and point out the importance of application of methods and models that are capable of treating uncertainties and are appropriate to keep under control the abundance of ecological effects of transportation in agriculture, making efforts towards the development of sustainable food and raw materials production.

The paper presents an analyses of shaft voltage and bearing current phenomena in electrical machines. An overview of the causes of these voltages and currents and their possible consequences is also given. The influence of the thyristor excitation system on the level of shaft voltages is examined, followed by the proposal of a measuring method and the preventive measures for shaft voltage reduction. Finally the paper reports the experimental measurements of shaft voltages on a turbo set that is a part of the Electric Power Industry of Serbia.

Micro, small and medium business units contribute to development of agribusiness only if adequate financial resources for founding and development are given. This paper analyzes the possibilities of financing micro, small and medium legal entities in agribusiness in Serbia, compared to large enterprises. Empirical research included a survey comprising 119 agribusiness units, grouped into three categories dependent on their size. The aim was to confirm that there are substantial differences between units of different sizes, concerning possibilities of accessing bank loans and concerning the process of evaluation of conditions for credit approval. Also, aim was to determine differences between the uses of necessary key economic measures in agribusiness. Results showed significant differences between each group of business units for the majority of the observed parameters. Consequently the small and medium-sized enterprises (SMEs) sector and especially entrepreneurs and farmers (micro units) only have limited access to financial resources and more financing costs compared to large enterprises.

The paper presents the results of deriving by calculation the local and total losses of the generator as well as efficiency determination of the revitalised hydro-generator unit A4 in HPP 'Djerdap 1'. In order to determine the generator losses and generator efficiency, measurements are performed during the acceptance tests of revitalised aggregate A4 in HPP 'Djerdap 1'.

Acceptance test results of the HE 'Djerdap 1' unit A4 excitation system are presented. The excitation system under study had been delivered and commissioned during unit A4 refurbishment works in 2013, while acceptance tests were conducted during 2014. The test purpose was to prove the contracted performances of the delivered excitation system. During the test was used calibrated measuring equipment which meets the requirements of technical standard GOST 11828-66.

In the paper, equivalent transfer function models of automatic and manual control of HE 'Pirot' unit A1 excitation system are presented. All determined parameter values are shown and discussed. Using experimentally derived step response records of the excitation system, the equivalent model parameters are identified and compared to previously adjusted values. The reactive voltage drops at generator terminals, as well as at the HV side of the step-up transformer, are determined.

In the last few decades, mental disorders resulting from substance abuse have become a frequent phenomenon, which features diverse forms and degrees of severity. In addition to being a medical and extremely harmful social phenomenon, substance abuse (commonly known as drug or narcotics abuse) is frequently a subject matter of research in many sciences or scientific disciplines, such as medicine, psychology, sociology, legal science, etc. Drug abusers may develop diverse mental disorders, which largely depends on the type of psychoactive substance which is being abused and the method of taking narcotics (including frequency, daily dose, mode of administration, etc.). In this paper, the author provides an overview of different types of mental disorders according to the applicable International Classification of Mental and Behavioral Disorders. The disturbance of mental functions due to drug abuse (which may or may not result in the development of a mental disorder) changes the perception and behaviour of drug users. The disturbance of mental functions becomes particularly prominent in the circumstances where substance abuse has turned into a drug addiction; the basic characteristic of the dependence syndrome is an irresistible urge (craving or even compulsion) to take the substance in order to enjoy its effects again or to avoid/relieve the drug addiction crisis or the abstinence syndrome, which may be extremely painful and agonizing. As a consequence of these mental disturbances and other disorders arising from drug addiction, human behaviour may be disrupted to such an extent that a person may demonstrate some criminal conduct, which ultimately makes these mental disorders highly relevant in the field of criminal law. Given the fact that the criminal offender is a drug abuser who may have different forms of mental disorders, there is a need to consider the offender's mental capacity (sanity), which ultimately makes these mental disorders highly relevant from the point of view of forensic psychiatry. The author's primary goal in this paper is to present the basic postulates underlying the perception of drug abuse and drug addiction in forensic psychiatry, both from the theoretical and practical point of view. In exploring the practical aspect of this issue, the author focuses on presenting the basic principles of forensic-psychiatric expertise of criminal offenders who have been diagnosed as having mental disorders caused by drug abuse. The expertise includes different aspects of assessing mental disorders: giving professional opinions on the offender's mental capacity (sanity), assessing the potential danger of recidivism or commission of a more serious criminal act, and giving proposals for relevant of security measures concerning the mandatory treatment of drug addicts both in outpatient clinics and in other relevant in-patient medical institutions. Given the fact that mental disorders stemming from drug abuse frequently have numerous financial, family and professional implications, the author presents some forensic psychiatric attitudes pertaining to the assessment of contractual capacity of these persons, the assessment of their working capacity (including the remaining working ability or temporary inability to work), the assessment of mental capacity for exercising the parental right or custodianship rights. In that context, the author provides the forensic psychiatric aspects of these mental disorders from the aspect of civil law. Drug abuse and drug addiction involve serious and complex socio-pathological problems which are difficult to treat/cure. This paper is the author's contribution to casting light on these issues, primarily from the aspect of forensic psychiatry.

This paper presents a technical solution for the replacement of the excitation system of the unit B1 in TPP 'Nikola Tesla B' as a part of the maintenance service in 2012. Since the generators of TPP 'Nikola Tesla B' have the greatest power in the power system of Serbia, it was necessary to achieve high reliability of the excitation system so that the process of producing electricity is not endangered Considering this, the implemented excitation system uses modern technology with redundancy both in the power and control blocks, which resulted in an increase in the hot reserve by 100%. In addition, it was necessary to adjust the excitation system to increased generator power and performance from 618MW to 667.5MW. In this paper, the main parameters of the excitation system are given: the power, the excitation system control, the thyristor ignition system, the event recorder system, the digital relay protection, as well as the measuring and signaling functions.

This paper presents the previous results of work and development of excitation systems with digital automatic voltage regulators regarding their design, development, manufacturing and commissioning. A special attention was paid to the characteristics of excitation system voltage regulator.

In this paper, procedure for AVR parameter estimation is proposed, based on step responses when synchronous generator in idle run. The exciter system includes AVR, thyristor rectifier and DC exciter. AVR is realized in the form of cascade control structure with two control loops. PID controller in the outer loop represents the primary controller. P controller in the inner loop represents secondary controller which enables the faster field current response time. The aim of procedure is to determine equivalent gain of PID controller and thyristor rectifier. The measurements used in the parameter estimation procedure are taken from fossil power plant 'Kolubara A', aggregate A5.

The excitation system of hydro unit in HPP 'Uvac' and results of testings of excitation system performed for achieving of unit's mathematical model are presented in this paper. Description of excitation system equipment, parameters of regulators and results obtained after testings are presented. The presented results showed that the regulators are properly adjusted and that the excitation system is completely functional and reliable.

Introduction. Psychological reactions are often comorbid with coronary risk factors and could be important for a six-month outcome. Objective. Determination of anxiety level, depression and aggression, persistence of risk health behaviour, stress life events, and coronary risk factors after coronary event and a predictive value of those parameters for six-month rehospitalization. Methods. In the group with Angina Pectoris (E1=30) and the group with Acute Myocardial Infarction (E2=33), there were applied, at baseline and after 6 months, the following: Semistructured Clinical Interview based on ICD-10, for depressive episode and anxiety disorder, Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD), KON-6 sigma Scale for aggression, Holms-Rahe Scale (H-R) for stress events and Questionnaire for risk behaviour: alcohol consumption, smoking, lack of physical activity. Group differences were assessed by t-test and chi-square test, p

Background/Aim. Chest pain often indicates coronary disease, but in 25% of patients there is no evidence of ischemic heart disease using standard diagnostic tests. Beside that, cardiologic examinations are repeated several times for months. If other medical causes could not be found, there is a possibility that chest pain is a symptom of psychiatric disorder. The aim of this study was to determine the presence of psychiatric syndromes, increased somatization, anxiety, stress life events exposure and characteristic of chest pain expression in persons with atypical chest pain and coronary patients, as well as to define predictive parameters for atypical chest pain. Method. We compared 30 patients with atypical chest pain (E group) to 30 coronary patients (K group), after cardiological and psychiatric evaluation. We have applied: Mini International Neuropsychiatric Interview (MINI), The Symptom Checklist 90-R (SCL-90 R), Beck Anxiety Inventory (BAI), Holms-Rahe Scale of stress life events (H-R), Questionnaire for pain expression Pain-O-Meter (POM). Significant differences between groups and predictive value of the parameters for atypical chest pain were determined. Results. The E group participants compared to the group K were younger (33.4 ± 5.4 : 48.3 ± 6,4 years, p < 0.001), had a moderate anxiety level (20.4 ± 11.9 : 9.6 ± 3.8, p < 0.001), panic and somatiform disorders were present in the half of the E group, as well as eleveted somatization score (SOM ≥ 63 -50% : 10%, p < 0.01) and a higher H-R score level (102.0 ± 52.2 : 46.5 ± 55.0, p < 0.001). Pain was mild, accompanied with panic. The half of the E group subjects had somatoform and panic disorders. Conclusion. Somatoform and panic disorders are associated with atypical chest pain. Pain expression is mild, accompained with panic. Predictive factors for atypical chest pain are: age under 40, anxiety level > 20, somatization ≥ 63, presence of panic and somatoform disorders, H-R score > 102, and a lack of positive diagnostic test of coronary disease. Defining of these parameters could be useful for early psychiatric evaluation of persons with atypical chest pain.

Because of their biological, and, especially, psychological and social characteristics, psychiatric patients can often become victims of very different modalities of activities which cause harm to them. These factors exist and have origin in social context where mentally ill live, but they can be factors that belong to whole social community as well. The aim of this paper is to review factors which contribute to victimisation of psychiatric patients, to point out a risk of their victimisation and their specific predispositions, as well as negative social circumstances which make psychiatric patients vulnerable to become victims in broader sense. In addition, the proposal of possible typology of psychiatric patients as victims is included as well.

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The selection of agricultural plants for sowing and planning the economic success in production is done in conditions of uncertainty and high risk. The factors, which cause the biggest uncertainty in achieving returns in agricultural production, can be quantified by the valuation method. The sense, value, manner and process of decision-making problems are determined by the cultural, social, temporal, value, as well as logical context. Fuzzy logic was developed more than five decades ago. T he characteristics of fuzzy logic include operating by fuzzy notions, imprecise authentication tables, and fuzzy inference rules. All these characteristics of fuzzy logic are highly important, especially if we try to exchange or supplement the long-dominating approach of decision making in agricultural management with the descriptive one. The criteria, limitations and performances of measures of alternatives bear in themselves some aspects of indefiniteness: in determinativeness, multiple aspects of meaning, incompleteness and fuzziness. Operational research offers optimization models aimed at finding an activity programme that will yield the best possible results. The models use precisely determined and known data. Constraints are also precisely determined, and the goal function is clearly defined, so that it can be formulated easily and simply. Reality, especially in the agricultural production, however, is different: very often we lack precise information on the value of individual input parameters, or the values of coefficients in constraint and goal functions, and imprecise formulation of limitations themselves is possible as well. This paper presents the valuation method at planning the structure of sowing: wheat, chamomile and mint. [ABSTRACT FROM AUTHOR]

In order to provide the best possible healthcare, managers need effective methods for decision making, as well as effective methods for management and improvement of a healthcare organization. Analysis of the demand is one of the key issues in healthcare organizations in that provides a reliable basis for efficient planning of future activities, of necessary material and financial and human resources. The main aim of this paper is to present the practical implementation of various quantitative methods in order to improve planning and organization of ambulance stations in Serbia. The results of detailed statistical analyses show that demand for emergency medical services follows some hourly, daily and monthly patterns. Observed regularities of the demand should be incorporated in operational, tactical and strategic plans of healthcare organizations in order to improve efficiency and achieve optimal allocation of scarce resources. [ABSTRACT FROM AUTHOR]