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The main tasks confirming the scientific novelty and practical value of the article is the development of a wireless sensor network for detecting intrusions and fires. A model of a sensor network for monitoring temperature and carbon monoxide levels has been developed. A device is proposed as a wireless sensor unit for monitoring temperature and carbon monoxide levels. A method is proposed for determining temperature jumps and carbon monoxide to determine penetrations and fires. The process of data transmission in a wireless sensor network for detecting fires and intrusions is investigated.

This article describes advantages and disadvantages of using methods for predicting the adjustment of the rates of modern digital money, which every year are gaining popularity among ordinary users - transors and entrepreneurs.Cryptocurrency is a set of concepts and technologies that together create basis for the digital money ecosystem. Money are used to save and transfer value between network members.The topicality of the topic is due to uncertainty about the appropriateness of using cryptocurrencies.

The paper investigates the problem of using fuzzy logic to build intelligent decision-making systems. The directions of application of fuzzy logic, as well as tools for modeling a fuzzy intelligent system for making decisions about the current state of an object are analyzed. The fuzzy logic is investigated and the corresponding fuzzy inference algorithm is chosen. All possible states of an intelligent system are determined, membership functions are constructed. Based on expert decisions, the system’s rule base was formed. For the practical implementation of an intelligent decision-making system, an air pollution analysis system was developed. This system allows assessing and making decisions about the current state of indoor air pollution.

The main tasks confirming the scientific novelty and practical value of this paper are the development, improvement and research of methods and technologies for constructing the Smart Home system. In this work, an intelligent home network monitoring system is developed, which is divided into subsystems for controlling electrical and electro-mechanical devices. A method has been developed for measuring the distance between wireless sensors in a smart home system, in order to determine the point of occurrence of an emergency situation. An algorithm for “bypassing” wireless sensor devices in a smart home system has been developed and studied, which allows it to function in areas of lack of direct visibility. A concept has been developed for placing sensors and ensuring the stable functioning of systems, which allows for timely response to emergency situations.

New principles and approaches to evaluating the effectiveness of the targeting strategy are considered, based on a comparison of the quality of the decisions made by the company depending on specific tasks.

This article presents technologies for evaluating cloud services based on the feedback test method. The main parameters of the formation of cloud architecture are determined, taking into account the requirements for security and reliability of resources. For the practical implementation of the technology for evaluating the efficiency of modern cloud services, based on the previously identified criteria, a software product was developed that determines the speed of downloading data for the cloud resource used. Analysis of the simulation results allows to qualitatively determine the effectiveness of cloud technologies for the user in multitasking, the necessary reliability and performance.

Nonlinear spectral broadening is widely used for applications like attosecond pulse generation, XUV sources, supercontinuum generation or ultrafast spectroscopy. In these cases the laser is typically spectrally broadened and compressed to reach pulse durations much shorter than originally available. For pulse energies in the millijoule regime, spectral broadening is routinely implemented using capillary optical fibers [1] with remarkable results in terms of output pulse durations and beam quality. In addition to fiber-based approaches, the application of multipass cells for spectral broadening [2] recently attracted increasing interest. These cells are capable of preserving a nearly Gaussian mode in the presence of nonlinear effects without a spatial filter or optical fiber, they are robust to input pointing, have a high throughput of more than 90% and can be used with high average powers and energies. In a multipass cell the nonlinear interaction with either gas [3] or a thin solid [2] provides a small amount of spectral broadening within each pass. Based on this concept we recently demonstrated output energies of almost 18 mJ by guiding near infrared pulses with a pulse duration of 1.3 ps and a repetition rate of 5 kHz through an argon filled multipass cell [4]. We obtained a broadening factor of over 33 and could show compressibility down to 41 fs. The energy was limited by the breakdown intensity of argon and the damage threshold of the used optics.

Reverse-GPS wildlife localization systems are emerging as a key technology for regional high-throughput wildlife tracking. Two such systems have been designed, implemented, and deployed (in six sites on three continents). Both of the existing systems suffer from limitations due to the modulation that is used by transmitters, which are attached to wild animals, and due to the detection and estimation algorithms that they use to detect transmissions and estimate their arrival times. This paper investigates key tradeoffs associated with three different modulation schemes that wildlife tags can plausibly use. The factors that we investigate include the ability to detect weak signals from distant tags, the ability to accurately estimate the time-of-arrival at a given SNR, and the computational cost of these detection and estimation algorithms. Our key contributions are (1) evidence that BPSK modulation is superior in essentially all relevant metrics, except perhaps chip availability, to FSK and OOK; (2) evidence that OOK is a second-best choice and its main drawback is poor performance under interference from other tags; (3) algorithms to inexpensively search the frequency-delay space at moderate and high SNRs. We also report on implementation efforts designed to integrate robust processing of BPSK tags into a wildlife tracking system.

This research work has resulted in the development of a web application that enables discrete event systems simulation to be created using a Petri-object approach. It provides the development of a model in two stages. In the first stage, the dynamics of the classes of objects are created using Petri net. In the second stage, the model is composed of objects with given dynamics. The simulation algorithm is based on stochastic Petri net with multichannel transitions and is implemented using Ruby. The web application enables the design of the model's dynamics by manipulation with graphics objects and saving it not only as a graphics object but also as a program method. This greatly improves the overall performance of the simulation model development.

The Petawatt Field Synthesizer (PFS) under construction at the Max-Planck Institute for Quantum Optics is an optical parametric chirped pulse amplification (OPCPA) system designed to generate few-cycle pulses with petawatt-scale peak power [1, 2]. Such pulses are of high interest for laser-matter interaction experiments, for example for the generation of isolated attosecond pulses with unprecedented efficiency [3]. Here we report on the current performance and upgrade plans of the OPCPA chain of PFS.

The Petawatt Field Synthesizer (PFS) light source has been under development at the Max-Planck-Institut fur Quantenoptik (Garching, Germany) for several years [1]. Its aim is to deliver few-cycle, waveform-controlled light pulses with unprecedented peak power at 10 Hz repetition rate from a compact (laboratory-scale) system.

The Petawatt Field Synthesizer (PFS) is an OPCPA driven light source that is currently being developed at the Max-Planck-Institut fur Quantenoptik in Garching, Germany. The target parameters are few-cycle, waveform-controlled light pulses with a repetition rate of 10 Hz and a peak power in the Petawatt regime [1]. The system relies on a cascaded broadband OPCPA that is pumped by a picosecond, all-diode-pumped Yb:YAG chirped-pulse-amplification (CPA) laser chain, the PFS pumplaser. In its final version, the pumplaser has to deliver nanosecond pulses with energies above 10 J at a wavelength of 1030 nm that can be compressed down to 1 picosecond and converted to 515 nm. Here, we report on the design and current performance of the new 2 J amplifier and discuss the design and ongoing development of the final 10 J amplifier.

High harmonics generated on solid surfaces (SHHG) promise a much higher efficiency compared to harmonics generated in gases. In case of ROM (Relativistically Oscillating Mirror) mechanism [1], conversion efficiencies up to the percent level are predicted [2]. An interesting property of ROM is that the maximum photon energy scales with the laser intensity. In addition an isolated attosecond (as) pulse can be generated when using a few-cycle driver pulse. However, for ROM, relativistic laser intensities above 1 × 1018 W/cm2 are required, which in combination with the few-cycle pulse duration is not readily available.

The dual-channel femtosecond laser system with each channel consisting of three BBO and LBO crystals based broadband parametric amplification stages of Ti:Sa laser radiation and relative jitter stabilization system to 110 as level is presented. For the first time coherent combining of two sequences of parametrically amplified femtosecond pulses with energy of ~ 150 mJ, 10 Hz repetition rate is experimentally realized. Coherent combining efficiency of over 90% is reached. Experimental results of parametrically amplified contrast measurement are presented with further comparison with simulation results based on the model of parametric luminescence evolution developed by us. In order to achieve petawatt power level schemes of multibeam pumping of the booster cascade of developed laser system are considered. Keywords—femtosecond pulses, parametric amplification, coherent beam combining, contrast, petawatt, multibeam pump

Algorithms for detection of broadband signal, reflected from the target, are proposed and analyzed. That ensures distinguishing of individual target elements in range and radial target velocity measurement by analyzing the mutual time delay of adjacent echo signals and by the law of value changes of the coefficients of mutual reading covariance in neighboring packet pulses. Estimates of standard deviation dependence and errors of radial target velocity measurement of signal-noise ratio and accompanied target type are obtained.

Results of comparative study of radar recognition with the use of narrowband and wideband signals as well as various recognition signatures are presented. The advantage of wideband radar signals is emphasized. The results show that use of wideband signals allow increasing the accuracy of radar measurements and radar immunity against interference providing the same detection range.

Review of advantages and problems of wideband radar is given. Some criteria of wideband (UWB) radar are discussed to avoid misunderstanding when only the relative signal bandwidth is used as a criterion. Brief historical outline of the first and follow up experiments by different authors is presented. Advantages and disadvantages of bandwidth widening can be compared using the computer simulation of scattering. Experience of various simulation methods use, their applications to the target detection, tracking and recognition problems are briefly discussed and compared with experiment. Interference immunity, electromagnetic compatibility, stealth of radiation (low probability of intercept- LPI) for radar, and the possibility of creation of antiLPI passive radar are also discussed.

The paper addresses the definition, properties and modeling requirements of wideband and ultra-wideband radars. It begins by establishing the criteria by which the designation 'wideband' might be specified, since the common definition based purely on relative bandwidth fails to invoke some important associations. Next, the role of simulation is discussed and a representative simulation environment is described. The advantages and disadvantages of increasing the signal bandwidth are then evaluated quantitatively in the context of signal detection, parameter measurement, and the recognition of aerial target classes and types, with reference to specific classes of interest. In practice, certain other issues arise, including the degree of immunity to interference and electromagnetic compatibility. These topics are discussed in terms of their dependence on signal bandwidth and the associated signal acquisition and processing. In addition, an emerging problem is the need to take into account the possibility of signal exploitation and LPI (low probability of intercept). The essence of the theory of unauthorized signal detection that limits the LPI possibilities is briefly considered.