Continuous execution of system dynamics models on input data stream

This article describes a new approach for system dynamics models execution. In most cases when model execution is involved it is performed on a set of static and known data, which are sent to the model as an input. And it is expected, that on the model output modeler will get a set of other system or event characteristics, computed by the model based on the input parameters. This approach still has the widest usage, but it is not the only one scenario, which is demanded by different industries. With growing popularity of concepts such as Internet of Things, demand in modeling based solutions, which take as input continuous data streams, has grown significantly. In comparison with stand-alone client-side modeling systems, cloud-based solutions, such as sdCloud, became a reasonable answer to such industry request. Such systems can provide an ability of continuous execution of system dynamics models. In other words, these systems are ready to accept an incoming data stream and perform model execution that will result in streaming modeling results back to the end-user. Running system dynamics models in parallel with the process it is describing allows to perform predictive modeling of the system status in the future, and it also allows to find additional hidden external impacts to the model. For example, such approach can be a base for predictive maintenance of complicated technical systems, because it allows computing nearest maintenance time more efficient

Mathematical model of liquid vapor compression system for multicircuit cooling systems of high mobile platform

© Research India Publications. The descriptions of the structure, the principle of operation and the mathematical model of the liquid-vapor compression cooling system, through which an effective cooling of a mobile platform power plant at elevated ambient temperature is possible. The proposed model allows to simulate the thermodynamic processes of heat and mass transfer and heat transfer, depending on the system load, its design parameters and the material of heat exchangers, the mass flow of refrigerant and coolant flow, taking into account the ambient temperature. The result of mathematical modeling showed that by the coolant temperature increase up to 127 °C, an average temperature pressure in a heat exchanger-condenser between the refrigerant and air increased. Therefore the amount of waste heat to the atmosphere was significantly increased. This will ensure an efficient operation of a cooling system at an elevated ambient temperature and will improve the weight and size of a cooling system in general

A mathematical model of the controlled axial flow divider for mobile machines

The authors give a mathematical model of the axial adjustable flow divider allowing one to define the parameters of the feed pump and the hydraulic motor-wheels in the multi-circuit hydrostatic transmission of mobile machines, as well as for example built features that allows to clearly evaluate the mutual influence of the values of pressure and flow on all input and output circuits of the system

Effect of membrane-active microbial autoregulators on the growth of cultured ras-transformed fibroblasts

Differential effects on the proliferation of individual vs. combined administration of high-and low-molecular-weight microbial autoregulators (extracellular RNase from Bacillus intermedius and anabiosis-inducing factor d 1) are reported for the first time for cultured cells of higher eukaryotes. Proliferation of ras-transformed mouse fibroblasts was affected by both autoregulators dose-dependently. The cytotoxic activity of individual regulators was directly related to their concentration. Unlike RNase, factor d 1 (which functions as a chemical chaperone) exerted reversible effects. Studies of the effects of combined administration of the autoregulators demonstrated that pretreatment of the cells with low-dose d 1 decreased the toxicity of RNase. Higher doses of d 1 were required to attenuate the effects of toxic agents with more pronounced membrane tropism. The results obtained suggest that a universal system regulating the physiological activity of cells is operative in taxonomically remote organisms. The operation of the system is based on sequential changes in the structural organization and function of subcellular structures induced by low-and high-molecular-weight autoregulators

Adaptation of System Dynamics Model Execution Algorithms for Cloud-based Environment

This paper presents a process of adaptation of system dynamics models execution algorithms to cloud-based environment. System dynamics is an aspect of systems theory as a method to understand the dynamic behaviour of complex systems. Existing modeling algorithms used in popular modeling solutions are either not available for free use or have several disadvantages which prevent them from being used in distributed cloud environment. Adaptation of execution algorithms aimed not only to adapt execution process to distributed parallel environments with higher reliability and wider range of possible applications, but also to improve system dynamics model execution performance. For example, existing algorithms of model execution which are not ready for distributed environments will fail to complete modeling task in case of hardware failure, and optimized ones are able to smoothly transfer execution process from one node to another with minimal impact on overall model execution progress. Such capabilities help to save many resources and, especially, time on execution re-runs. In this paper described algorithms and approaches designed for sdCloud solution which are focused on transferring execution of system dynamics models into distributed cloud-based environment and shown extra benefits brought to modeling process by shift to the cloud

Simulation of parameters of hydraulic drive with volumetric type controller

© Published under licence by IOP Publishing Ltd. The article presents a mathematical model of volumetric type hydraulic drive controller that allows to calculate the parameters of forward and reverse motion. According to the results of simulation static characteristics of rod's speed and the force of the hydraulic cylinder rod were built and the influence of the angle of swash plate of the controller at the characteristics profile is shown. The results analysis showed that the proposed controller allows steplessly adjust the speed□ of hydraulic cylinder's rod motion and the force developed on the rod without the use of flow throttling

Effect of Membrane-active Microbial Autoregulators on the Growth of Cultured ras-Transformed Fibroblasts

Differential effects on proliferation of individual vs. combined administration of high- and low-molecular-weight microbial autoregulators (extracellular RNase from Bacillus subtilis and anabiosis-inducing factor d1) are reported for the first time for cultured cells of higher eukaryotes. Proliferation of ras-transformed mouse fibroblasts was affected by both autoregulators dose-dependently. The cytotoxic activity of individual regulators was directly related to their concentration. Unlike RNase, factor d1 (which functions as a chemical chaperone) exerted reversible effects. Studies of the effects of combined administration of the autoregulators demonstrated that pretreatment of the cells with low-dose d1 decreased the toxicity of RNase. Higher doses of d1 were required to attenuate the effects of toxic agents with more pronounced membrane tropism. The results obtained suggest that a universal system regulating the physiological activity of cells is operative in taxonomically remote organisms. The operation of the system is based on sequential changes in the structural organization and function of subcellular structures, induced by low- and high-molecular-weight autoregulators

The role of bacterial growth autoregulators (alkyl hydroxybenzenes) in the response of staphylococci to stresses

The investigation of the response of a batch culture of Staphylococcus aureus to exogenous alkyl-substituted hydroxybenzenes (AHBs), chemical analogues of anabiosis autoinducers, showed that C 1-AHB at concentrations from 5 μM to 1.5 mM did not influence the culture growth, whereas the more hydrophobic C 6-AHB inhibited it at concentrations of 0.5 mM and higher. Either of the AHBs drastically enhanced the phenotypic dissociation of staphylococcal cultures, which manifested itself in an increase in the fraction of cells producing small nonhemolyzing colonies of G type when plated on solid media with erythrocytes. In a submerged staphylococcal culture, the relative number of cells producing G-type colonies varied from 10 to 90%, depending on the concentration of the AHB added. The growth of S. aureus in the presence of AHBs also enhanced cell tolerance to heat shock (heating at 45 or 60°C for 10 min). The role of AHBs, which are structural modifiers of membranes and possess chaperone activity, in the mechanisms responsible for cell tolerance and phenotypic dissociation of microbial populations is discussed

Super-long Anabiosis of Ancient Microorganisms in Ice and Terrestrial Models for Development of Methods to Search for Life on Mars, Europa and other Planetary Bodies

Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects

The effect of anabiosis autoinducers on the bacterial genome

The mutagenic activity of chemical analogues of microbial anabiosis autoinducers (the autoregulatory d 1 factors of cell differentiation), which act to inhibit cell proliferation, to enhance cell tolerance, and to induce the transition of cells to anabiotic state, was studied using the Ames test. In the range of concentrations studied (0.1 to 100 μg/ml), alkyl-substituted hydroxybenzenes (AHBs) differing in hydrophobicity, i.e., methylresorcinol (C 1-AHB) and hexylresorcinol (C 6-AHB), as well as unsubstituted resorcinol, showed different growth-inhibiting and mutagenic effects. C 6-AHB was found to inhibit the growth of Salmonella typhimurium TA100 and to induce its mutagenesis at a rate of 1.8 revertants/nmol. C 1-AHB taken at low concentrations not only failed to inhibit bacterial growth but even stimulated it and exerted an antimutagenic effect. Unsubstituted resorcinol virtually did not influence bacterial growth and showed weak mutagenic activity. The growth-inhibiting effect of elevated C 6-AHB concentrations correlated with the degree of the transition of the original phenotype producing S-type colonies to a phenotype producing R-type colonies. The role of AHB homologues, as microbial autoregulators with mutagenic activity, in the regulation and correlation of two processes (the phenotypic dissociation of microbial populations and the formation of resting microbial forms) is discussed. The accumulation of AHBs in senescent microbial cultures may induce adaptive mutations, change the expression of genes, and promote the development of minor cell subpopulations (phenotypes), thus providing for the adaptation of these cultures to varying environmental conditions