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The article discusses the new electronic data-driven system, the Integrated Pay and Personnel System-Army, which will bring the Army's former paper-based system into the 21st century by giving soldiers, leaders, and units unprecedented access to information in one place. It is a decentralized personnel database in which each Army component is maintained separately accessible only by human resources professionals.

Blockchain is well known as a decentralized and distributed public digital ledger, and is currently used by most cryptocurrencies to record transactions. One of the fundamental differences between blockchain and traditional distributed systems is that blockchain's decentralization relies on consensus protocols, such as proof of work (PoW). However, computation systems, such as application specific integrated circuit (ASIC) machines, have recently emerged that are specifically designed for PoW computation and may compromise a decentralized system within a short amount of time. These computationally resourceful miners challenge the very nature of blockchain, with potentially serious consequences. Therefore, in this paper, we propose a general and flexible PoW method that enforces memory usage. Specifically, the proposed method blocks computationally resourceful miners and retains the previous design logic without requiring one to replace the original hash function. We also propose the notion of a memory intensive function (MIF) with a memory usage parameter k (k MIF). Our scheme comprises three algorithms that construct a k MIF Hash by invoking any available hash function which is not k MIF to protect against ASICs, and then thwarts the pre-computation of hash results over a nonce. We then design experiments to evaluate memory changes in these three algorithms, and the findings demonstrate that enforcing memory usage in a blockchain can be an effective defense against computationally resourceful miners. [ABSTRACT FROM AUTHOR]

The problem of observer-based decentralized event-triggered H ∞ control for networked systems is investigated in this paper. The system measurements and control inputs are grouped into several nodes. An event-triggered transmission scheme is introduced to choose those necessary signals to be transmitted from the plant to the observer and from the controller to the actuator, where signals from control input nodes and from measurement nodes are released not necessarily synchronously. Under the decentralized event-triggered transmission scheme, H ∞ performance analysis for the resultant closed-loop system is made, and an algorithm to designing suitable observers and controllers is presented as well. Moreover, a sufficient condition is derived such that the inter-event time is strictly greater than zero. Finally, two examples are given to show the effectiveness of the method proposed in this paper. [ABSTRACT FROM AUTHOR]

In this paper we derive a sufficient condition for which unstructured decentralised fixed modes (UDFMs) of a LTI system cannot be stabilised by any form of decentralised output feedback controllers. The sufficient condition establishes the link between special UDFMs (SUDFMs) and quotient fixed modes (QFMs). The link between UDFMs and QFMs provides an unequivocal answer, which has up until now eluded researchers, as to why some UDFMs cannot be eliminated by sampled-data controllers. In addition, we use this link to highlight the role system parameter uncertainties can play in shifting stabilisable DFMs to UDMFs or QFMs and vice versa. Numerical examples are presented to illustrate all aspects of the paper. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of asynchronous event-triggered control for decentralized networked systems. A group of geographically distributed sensors rather than a centralized sensor are deployed to asynchronously sample and measure the system’s state signal. First, an asynchronous decentralized event-triggered transmission scheme is developed to check which sensor measurements should be transmitted to a remote control station via a network channel. Second, a series of artificial piecewise functions are introduced to incorporate the simultaneous effects of intermittent transmissions and network-induced delays into multiple delays. By considering distribution characteristics of these delays and using a switching Lyapunov–Krasovskii functional, criteria on L 2 stability analysis and control design are derived. Finally, a well-used batch reactor system is employed to illustrate the effectiveness of the proposed control design method. [ABSTRACT FROM AUTHOR]

This paper reviews the experiences with an integrated urban management Masters course, which saw an increase from 20 participants to 400 students in a period of 5 years. After a few years it became clear that it was difficult to absorb this number of Masters students in the government sector and that their skills did not match all the requirements. The paper looks at the external factors determining the success of the integrated urban management Masters course, and the desire of the Ethiopian government to make decentralization a reality. It also analyses the internal factors leading to positive outcomes of the interventions over time. The increasing complexity of urban problems cannot be managed by general urban managers; therefore specialized Masters programmes were launched. The programme evolved over time, reflecting the priorities of the Ethiopian government. Starting as a unified programme, the course was split into a series of specializations, focusing on water-related and environmental issues. The cooperation evolved over the period of the relationship into a partnership with leadership on the Ethiopian side. This contributed to the success in terms of the capacity built, the number of people trained, and their contribution to dealing with water and environmental problems in an urban context. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a general chaotification algorithm for a class of nonlinear discrete-time dynamical systems. Based on a given nonlinear discrete-time system, the new chaotification algorithm uses the decentralized linear state feedback control and a class of nonlinear functions that are only required to satisfy some mild assumptions to construct a chaotic nonlinear system. The sine and sawtooth function used in the existing literature on chaotification only are the special cases of the proposed nonlinear function. Based on the corrected version of the Marotto theorem, we mathematically prove that the constructed nonlinear system is indeed chaotic in the sense of Li and Yorke. In particular, an explicit formula for the computation of chaotification parameters is also obtained. The theoretical results in this paper can be used to supervise one to construct different chaotification algorithms. [Copyright &y& Elsevier]

In this paper, a decentralized adaptive backstepping control scheme is proposed for a class of interconnected nonlinear systems with unknown actuator failures. By introducing a smooth function, some integrable auxiliary signals and a bound estimation approach, the effect of actuator failures is successfully compensated for. The proposed scheme has the following features: (1) the total number of failures is allowed to be infinite; (2) global stability of the overall closed-loop system is achieved without any bound knowledge of uncertainties; (3) all system outputs converge to zero asymptotically regardless of the possibly infinite number of failures and the unknown interactions among subsystems. Simulation results on coupled inverted double pendulums are presented to illustrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper is concerned with the centralized and decentralized adaptive output feedback control problem for a class of uncertain interconnected nonlinear systems with unmodeled dynamics and unmeasured states. The known requirement of the upper bounds of dynamic disturbances and coupling terms in the considered system is avoided. Decentralized observers are constructed based on the K-filters to estimate the unmeasured states of each subsystem. In the design of adaptive output feedback dynamic surface control, the unknown nonlinear functions are directly approximated by neural networks, while the coupling terms being lumped together with those unknown continuous functions produced in deduction are approximated as a whole. Using the defined compact set in the stability analysis, some unknown nonlinear continuous functions are dealt with effectively. It is proved that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded. Simulation results are provided to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach for the coordination of a team of autonomous sensor platforms searching for lost targets under uncertainty. A real-time receding horizon controller in continuous action space is developed based on a decentralized gradient-based optimization algorithm and by using the expected observation as an estimate of future rewards. The expected observation is a cost-to-go heuristic that estimates the goodness of the states that the platforms could reach. It permits the decision making algorithm to take into account the information on the whole environment, reducing the time needed to detect the target. The heuristic, modeled as a sensor, allows us to develop a new team utility function with low computational cost and high performance. It can be applied to challenging scenarios such as multi-target search with complex and non-uniform target probability distributions. Through simulation and statistical analysis, we show the advantages of using the expected observation heuristic in multi-vehicle coordination for search applications. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an output feedback stabilisation problem is considered for a class of large scale interconnected time delay systems with uncertainties. The uncertainties appear in both isolated subsystems and interconnections. The bounds on the uncertainties are nonlinear and time delayed. It is not required that either the known interconnections or the uncertain interconnections are matched. Then, a decentralised delay-dependant static output feedback variable structure control is synthesised to stabilise the system globally uniformly asymptotically using the Lyapunov Razumikhin approach. A case study relating to a river pollution control problem is presented to illustrate the proposed approach. [Copyright &y& Elsevier]

Network management constitutes an important element in telecom companies by contributing to the improvement of its efficiency and competitiveness. ETECSA finds itself absorbed in improving the available access and data management technologies. Its decentralization to the territorial management centers is one of this initiative' palpable results. This paper deals with elements, architectures, and functional areas of network management, and presents both the completed work for the implementation of access and data decentralization management in the Las Tunas Regional Division, the main results obtained in terms of provision, supervision, and diagnosis of said technologies. [ABSTRACT FROM AUTHOR]

Abstract: Based on a fictitious market model, a decentralized approach is presented for the workstation scheduling in a CNC workshop. A multi-agent framework is proposed, where job agents and resource agents act as buyers and sellers of resource in the virtual market. With cost and benefit calculation of these agent activities, which reflects the state of the production environment, various, and often conflicting goals and interests influencing the scheduling process in practice can be balanced through a unified instrument offered by the markets. The paper first introduces a heuristic procedure that makes scheduling reservations in a periodic manner. A multi-agent framework is then introduced, in which job agents and resource agents seek appropriate job–workstation matches through bidding in the construction of the above periodic “micro-schedules”. A pricing policy is proposed for the price-directed coordination of agent activities in this. Simulation results demonstrate the feasibility of the proposed approach and give some insights on the effects of some decision making parameters. Future work will be focused on the designing of some more sophisticated coordination mechanism and its deployment. [Copyright &y& Elsevier]