Multiuser wireless channel simulation for communication systems with nonparametric reception
When combined with error-correction codes reception techniques based on nonparametric hypothesis testing and order statistics provide strong immunity to different types of interference including multiuser interference. That makes communication systems using such reception techniques most appealing candidates for various applications such as Machine-to-Machine (M2M) communications and Internet Of Things (IOT). Unfortunately analytical treatment of communication systems with nonparametric reception remains a cumbersome task. Therefore simulation remains the main tool for the development of such systems. For multiuser systems supporting hundreds of active users and operating in fading channels (e.g. IOT) time spending grows drastically hampering the design process. Thus the development of simplified multiuser channel models is of great interest. In this paper two simplified mathematical models of multiuser interference for the case of a single user nonparametric reception are proposed. The effectiveness of the proposed models is compared by means of modulation. Special attention is paid to the problem of software implementation of the models proposed.
The development of IoT systems, especially in the field of Industrial Internet of things with a large number of end devices is a complex scientific and technical problem. Inability to take into account the number of factors at the early stage leads to a negative result. This document demonstrates the scientific approach to the creation of the above systems. The IoT protocols, the IoT system architecture and its components are described in this article. The problems arising in the design of IoT systems are described. The basic characteristics of the most common protocols are systematized. The method for solution of the actual scientific and applied problem, allowing to design the IoT system, taking into account various fundamental parameters including the frequency range, bandwidth, data transfer rate, radiated power, range, work intensity, as well as the fundamental constraints, is proposed. As a result of the application of the described method, the optimal IoT protocol can be chosen to build a system, or to determine and optimize the parameters of the proprietary protocol. That makes it possible to build a reliable and scalable IoT system for the solution of the relevant experimental problems.
In what follows a channel model that describes a class of communication systems employing a certain nonparametric receiver is considered. In particular a block coded transmission via the channel under consideration and soft-input mismatched decoding are considered. The paper deals with a problem of finding an upper bound on the probability of erroneous decoding. In order to obtain the bound in question a second version of the Duman-Salehi bound is applied. For the system under consideration a closed form for the normalized tilting measure minimizing the bound under consideration is obtained
Low Power Wide Area Networks (LPWAN) is a new solution for the Internet of Things (IoT). This type of networks already has several specific implementations like LoRa, Sigfox, Weightless, RPMA and others. Due to long wireless range, low power consumption and numerous nodes low speed overlay networks can be organized on top of LPWAN. Small pieces of data like text messages, low-quality photographs, etc. can be sent over these overlays and can be of significant importance for emergency services. When organizing an overlay network over LPWAN it is important to meet the Quality of Service (QoS) requirements present in the base network to prevent malfunction of its services. This paper presents the results of experimental study of QoS metrics measurement in LoRaWAN networks.
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Event logs collected by modern information and technical systems usually contain enough data for automated process models discovery. A variety of algorithms was developed for process models discovery, conformance checking, log to model alignment, comparison of process models, etc., nevertheless a quick analysis of ad-hoc selected parts of a journal still have not get a full-fledged implementation. This paper describes an ROLAP-based method of multidimensional event logs storage for process mining. The result of the analysis of the journal is visualized as directed graph representing the union of all possible event sequences, ranked by their occurrence probability. Our implementation allows the analyst to discover process models for sublogs defined by ad-hoc selection of criteria and value of occurrence probability
The geographic information system (GIS) is based on the first and only Russian Imperial Census of 1897 and the First All-Union Census of the Soviet Union of 1926. The GIS features vector data (shapefiles) of allprovinces of the two states. For the 1897 census, there is information about linguistic, religious, and social estate groups. The part based on the 1926 census features nationality. Both shapefiles include information on gender, rural and urban population. The GIS allows for producing any necessary maps for individual studies of the period which require the administrative boundaries and demographic information.
Existing approaches suggest that IT strategy should be a reflection of business strategy. However, actually organisations do not often follow business strategy even if it is formally declared. In these conditions, IT strategy can be viewed not as a plan, but as an organisational shared view on the role of information systems. This approach generally reflects only a top-down perspective of IT strategy. So, it can be supplemented by a strategic behaviour pattern (i.e., more or less standard response to a changes that is formed as result of previous experience) to implement bottom-up approach. Two components that can help to establish effective reaction regarding new initiatives in IT are proposed here: model of IT-related decision making, and efficiency measurement metric to estimate maturity of business processes and appropriate IT. Usage of proposed tools is demonstrated in practical cases.
Let G be a semisimple algebraic group whose decomposition into the product of simple components does not contain simple groups of type A, and P⊆G be a parabolic subgroup. Extending the results of Popov , we enumerate all triples (G, P, n) such that (a) there exists an open G-orbit on the multiple flag variety G/P × G/P × . . . × G/P (n factors), (b) the number of G-orbits on the multiple flag variety is finite.
I give the explicit formula for the (set-theoretical) system of Resultants of m+1 homogeneous polynomials in n+1 variables