Josip Stepanić

Approach to a Quantitative Description of Social Systems Based on Thermodynamic Formalism

I ns tiu e of S c al Sc e ces I vo Pilar, Marulice rg 19/1, Zagreb, CrE-mail: Mislav.Stjepan.Zebec@ipdi.hr and Kreso.Perackovic@ipdi.hrReceived: 11 February 2000 / Accepted: 14 July 2000 / Published: 28 July 2000Abstract: Certain statistical aspects of social systems are described by appropriately definedquantities named social potentials. Relations between social potentials are postulated bydrawing an analogy with thermodynamics relations between thermodynamic potentials, thusobtaining a toy model of some of the statistical properties of social systems. Within thismodel, an interpretation of a socially relevant acting (acting as opposed to action, see ref.[1]) that does not invoke structural changes in social systems, is given in terms of social po-tentials.Keywords: social systems theory, thermodynamics, social potentials, entropy and tempera-ture of social systems.IntroductionStudy of social systems requires the application of statistical methods to their description and givesresults of social system research in terms of statistical data. The existence of rich statistics usually, butnot necessarily, implies some underlying structure or even dynamics. Bearing in mind the very conceptof social systems, it is reasonable to assume the existence of some sort of dynamics describing socialsystems that leads to the observed statistics. The present level of knowledge of a quantitative descrip-tion of social systems [2] implies that the formulation of complete and consistent theory is a formidabletask.

Contribution to classification of buried objects based on acoustic impedance matching.

Determination of material the buried objects are made of could contribute significantly to their recognition, or classification. This is important in detecting buried antipersonnel landmines within the context of humanitarian demining, as well as in a variety of other applications. In this article the concept has been formulated of the approach to buried objects material determination starting with ultrasonic impulse propagation analysis in a particular testing set configuration. The impulse propagates through a characterized transfer material in such a way that a part of it, a reflected wave, carries the information about the buried objects surface material acoustic impedance. The limit of resolution capability is theoretically analyzed and experimentally evaluated and the influencing factors described. Among these, the contact between clean surfaces of the transfer material and buried object is emphasized.

Comparison of social and physical free energies on a toy model.

Social free energy has been recently introduced as a measure of social action obtainable in a given social system, without changes in its structure. The authors of this paper argue that social free energy surpasses the gap between the verbally formulated value sets of social systems and the quantitatively based predictions. This point is further developed by analyzing the relation between the social and the physical free energy. Generically, this is done for a particular type of social dynamics. The extracted type of social dynamics is one of many realistic types of the differing proportion of social and economic elements. Numerically, this has been done for a toy model of interacting agents. The values of the social and physical free energies are, within the numerical accuracy, equivalent in the class of nontrivial, quasistationary model states.

Describing social systems using social free energy and social entropy

Purpose – Constant question in determination of a social system state is how to obtain a sufficient quantity of information with a small enough, manageable indicator set.Design/methodology/approach – The concept is developed in a thorough analysis of strengths and weaknesses of existing approaches, and in thorough contrasting the proposed solutions with these.Findings – The social free energy and social entropy overcome the gap between the meta‐theoretically founded quantities and indicators related to social system state description. The social free energy measures the totality of resources used for social system preservation during changes in environment. The social entropy measures the number of different realisations of a particular state.Practical implications – Combination of social free energy and social entropy is on the one hand a set of quantities easily determinable from available data, and on the other hand a set of indicators intuitively connected with social system states. We relate the syst...

Simulacija mjerenja kvalitete usluge primjenom modeliranja pomoću agenata

Quality level, achieved by a service-providing company, has complex dynamics. It is demanding to optimise the company’s performances in a realistic, non-characterised environment. This article contributes to stated optimisation by formulating the agent-based model for performance of a service-providing company. A set of elements and relations representing a structure of such a company is described and explained. In addition, some elements occurring in realistic situations are not included in the model and their absence is explained. Parameters of the model are divided into two groups. First group consists of parameters describing interactions between the company and its environment and second group of the parameters describing internal interactions among the company’s elements. Interactions are represented using time-dependent information entropy. Quality of the company’s performances is related to values of accompanying information entropies. Relatively simple agent-based model makes possible reliable representations of a variety of observed functions of service companies.

A Contribution to Considerations of the Role of Embedded Systems

Abstract Background: Embedded systems are a ubiquitous part of modern civilisation. Trends point to further intensification of their use. In this article we discuss long-term implications of that process, from the point of view of systems science. Objectives: On a general level, we relate embedded systems to a general class of objects and argue about their role in human life. On a somewhat more specific level, we consider in more details the development of unmanned aerial vehicles. Methods/Approach: In order to achieve the set objectives, we conducted inductive theoretical considerations and presented the results in this section. Results: The hierarchy of notions relating human civilization to environment is established, and embedded systems are positioned within it. Conclusions: Broadening and intensification of the use of embedded systems is a gradual process, heavily intertwined with societal changes. The case study of the development of the unmanned aerial vehicles reveals the potentials of the concept of embedded systems, also in the area of human resources management

A computational approach to parameter identification of spatially distributed nonlinear systems with unknown initial conditions

In this paper, a high-precision algorithm for parameter identification of nonlinear multivariable dynamic systems is proposed. The proposed computational approach is based on the following assumptions: a) system is nonlinearly parameterized by a vector of unknown system parameters; b) only partial measurement of system state is available; c) there are no state observers; d) initial conditions are unknown except for measurable system states. The identification problem is formulated as a continuous dynamic optimization problem which is discretized by higher-order Adams method and numerically solved by a backward-in-time recurrent algorithm which is similar to the backpropagation-through-time (BPTT) algorithm. The proposed algorithm is especially effective for identification of homogenous spatially distributed nonlinear systems what is demonstrated on the parameter identification of a multi-degree-of-freedom torsional system with nonlinearly parameterized elastic forces, unknown initial velocities and positions measurement only.

Static Sensitivity of the Aerial Load Transport by Two Rotocopter Unmanned Aerial Vehicles

Aerial load transport by Unmanned Aerial Vehicles (UAVs) can be performed either using a single UAV or using a group of cooperative UAVs. The latter option is assumed more reliable, yet more demanding regarding the control and required power, than the former one. This article theoretically evaluates power consumption for aerial load transport by the use of two UAVs and compares it with the power consumption in case of a single UAV. In all treated cases, we assume a stationary level flight. For the stated comparison the theoretical model for aerial load transport by two identical UAVs is formulated. Generic flight characteristics and UAVs characteristics are prescribed, and corresponding solutions of the model evaluated. Independent parameters of the model are masses of the UAVs and the load, as well as flight velocity. Variables in the model are vertical and horizontal distances between the UAVs. The emphasis is put on the available instantaneous power and sensitivity to occasional wind gusts. We extract intervals of the model parameters for which each of the two UAVs is less loaded than a UAV which solitary carries a load. The sensitivity to wind gusts is lesser in configurations in which one UAV carries most of the load while the other provides the additionally needed instantaneous power.

Simulation modelling of a company providing two qualitatively different services to market

Simulation modelling is applied onto a market dynamics of a company conducting two qualitatively different services and has a bounded total daily volume. The model contains qualitatively and in a simplified form the characteristics of the dynamics of a general service providing company. The company applies a single strategy how to influence, thus minimise, the number of agents who wait for a given service. The strategy is realised by changing the relative proportion of the daily conducted services. Rather small modification of priority level between the two services influences considerably both the number and the type of end users who wait for a particular service. The model enables the researchers to test different strategies how to control the number of end users who wait for services, by proper changes in priority level of services conducted. The fact important for practitioners is that partial optimisation is achieved through slight difference in priorities between the services. (Received in October 2015, accepted in January 2016. This paper was with the authors 1 week for 1 revision.)