A novel scalable and privacy-preserving distributedparallel optimization that allows the participation of large-scale aggregation of prosumers with residential PV-battery systems in the market for the ancillary servi...
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A novel scalable and privacy-preserving distributedparallel optimization that allows the participation of large-scale aggregation of prosumers with residential PV-battery systems in the market for the ancillary service (ASM) is proposed in this paper. To consider both reserve capacity and energy, day-ahead and real-time stages in the ASM are considered. A method based on hybrid Variable Neighborhood Search (VNS) and distributedparallel optimization is designed for the day ahead and real-time optimization. Different distributed optimization methods are compared and designed and a new distributed optimization method based on Linear Programming (LP) is proposed that outperforms previous methods based on integer and Quadratic programming (QP). The proposed LP-based optimization can be easily coded up and implemented on microcontrollers and connected to a designed Internet of Things (IoT) based architecture. As confirmed by simulation results, carried out considering different realistic case studies, both day-ahead and real-time proposed optimization methods, by allocating the computational effort among local resources, are highly scalable and fulfil the privacy of prosumers.
The Main Injector (MI) was commissioned using data acquisition systems developed for the Fermilab Main Ring in the 1980s. New VME-based instrumentation was commissioned in 2006 for beam loss monitors (BLM)[2], which p...
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Great strides have been made in computational methods for social systems. However, real-world modeling problems require novel computational techniques to support modeling and analyses with time and resource constraint...
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Great strides have been made in computational methods for social systems. However, real-world modeling problems require novel computational techniques to support modeling and analyses with time and resource constraints. The emergence of parallel architectures, in the form of multicore/manycore processors, and distributed platforms, have led to the formulation of new approaches for large-scale information processing, modeling and simulation, and new tools for analysis. Due to the inherent interdisciplinary nature of the research in computational social systems, techniques that utilize parallel and distributed algorithms, systems, and methodologies continue to evolve in diverse disciplines. This special issue provides a platform to bring together these researchers to showcase innovative research in computational social systems that leverage the emerging trends in parallel and distributed processing, algorithms, computational modeling, and high-performance computing. The call for papers was issued in 2017, with the submission deadline of December 29, *** received a number of strong submissions. The papers went through a rigorous review process and six high-quality papers were selected. The special issue papers are distributed across multiple issues of the TRANSACTIONS, specifically the last two issues of 2018 and this issue. We provide brief descriptions of the papers below.
Worldwide streams of data are expanding continuously, resulting in an accelerating need to efficiently and timely handle these large amounts of data that arrive continuously. In-memory computing is used to meet perfor...
Worldwide streams of data are expanding continuously, resulting in an accelerating need to efficiently and timely handle these large amounts of data that arrive continuously. In-memory computing is used to meet performance related requirements like latency and throughput that are extremely important in Data Stream Processing (DSP) applications. Several different technologies have emerged specifically to address the challenges of processing high-volume, real-time data, exploiting on-the-fly computations. distributed Stream Processing systems (DSPSs) assign applications’ processing tasks to the available resources and route streaming data between them. Efficient scheduling of processing tasks can reduce application latencies and eliminate network congestions. However, the available in-built scheduling techniques of DSPSs are far from optimal. In this thesis, we need to solve the task scheduling problem which focuses on which tasks to be allocated on which resources, and controls the order of job execution. An overview of the available DSPSs is presented and a classification of the existing scheduling policies is provided. In this way, useful information about the matters to consider when designing an effective scheduling policy is revealed. Then, a general formulation of the task scheduling problem is presented and a matrix-based, linear scheme is provided. Differently from existing research efforts, that rarely consider memory utilization in their analysis, the derived scheme is performed in a memory-efficient and well-balanced manner. It takes advantage of pipelines to efficiently handle applications, where there is need for heavy communication (all-to-all) between tasks, assigned to pairs of components. The scheme proposed in this thesis is static. However, when it comes to streams of data, the input load usually fluctuates drastically over time. Dynamic schemes use run-time adaptations and task re-scheduling to handle possible changes in the cluster but this usual
This article studies the core maintenance problem for dynamic graphs which requires to update each vertex's core number with the insertion/deletion of vertices/edges. Previous algorithms can either process one edg...
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This article studies the core maintenance problem for dynamic graphs which requires to update each vertex's core number with the insertion/deletion of vertices/edges. Previous algorithms can either process one edge associated with a vertex in each iteration or can only process one superior edge associated with the vertex (an edge < u, v > is a superior edge of vertex u if v' core number is no less than u's core number) in each iteration. Thus for high superior-degree vertices (the vertices associated with many superior edges) insertions/deletions, previous algorithms become very inefficient. In this article, we discovered a new structure called joint edge set whose insertions/deletions make each vertex's core number change at most one. The joint edge set mainly contains all the superior edges associated with the high superior-degree vertices as long as these vertices are 3(+)-hop independent. Based on this discovery, faster parallel algorithms are devised to solve the core maintenance problems. In our algorithms, we can process all edges in the joint edge set in one iteration and thus can greatly increase the parallelism and reduce the processing time. The results of extensive experiments conducted on various types of real-world, temporal, and synthetic graphs illustrate that the proposed algorithms achieve good efficiency, stability and scalability. Specifically, the new algorithms can outperform the single-edge processing algorithms by up to four orders of magnitude. Compared with the matching based algorithm and the superior edge based algorithm, our algorithms show a significant speedup up to 60x in the processing time.
This paper proposes a concept of low-cost industrial wireless sensor network integrating the power consumption efficient ESP32 chip. The main focus is given on best practices of various sensors integration into real-T...
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ISBN:
(纸本)9781728110592
This paper proposes a concept of low-cost industrial wireless sensor network integrating the power consumption efficient ESP32 chip. The main focus is given on best practices of various sensors integration into real-time Operating System (RTOS) of ESP32 devices. The work proposes an architecture for data collection, security and possibility of data analysis. Energy effectiveness is estimated for battery usage in different modes of the chip. The last part of this work presents the conclusions and guidelines for future work. Road map of a distributed modeling
This work aims at the development of tools for supporting modelling and analysis of timed systems by Stochastic Reward Nets (SRN). In a first approach it was proposed and experimented a formal reduction of SRN over Ti...
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ISBN:
(纸本)9781665433266
This work aims at the development of tools for supporting modelling and analysis of timed systems by Stochastic Reward Nets (SRN). In a first approach it was proposed and experimented a formal reduction of SRN over timed Automata (TA) in the context of the Uppaal popular toolbox. The reduction has the merit to allow both exhaustive model checking of an SRN model, useful for the assessment of qualitative properties (e.g., absence of deadlocks, occurrence of particular event sequences etc.), and quantitative analysis through the statistical model checker, which is based on simulations. However, although Uppaal enabled formal reasoning on the semantics of SRN, its practical usage suffers of scalability problems, that is it can introduce severe limitations in time and space when studying complex models. To cope with this problem, this paper describes a Java implementation of the SRN operational core engine, using the lock-free and efficient Theatre actor system which permits the parallel simulation of large models. The realization can be used for functional property checking on an untimed version of a source SRN model, and quantitative estimation of measurables through simulations. The paper discusses the design and implementation of the core engine of SRN on top of Theatre, together with supported intuitive configuration process of an SRN model, and reports some experimental results using a scalable grid computing model. The experiments confirm Theatre/SRN are capable of exploiting the potential of modern multi-core machines and can deliver good execution performances on large models.
In this paper we discuss sparsification of worker-to-server communication in large distributedsystems. We improve upon algorithms that fit the following template: a local gradient estimate is computed independently b...
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In this paper we discuss sparsification of worker-to-server communication in large distributedsystems. We improve upon algorithms that fit the following template: a local gradient estimate is computed independently by each worker, then communicated to a master, which subsequently performs averaging. The average is broadcast back to the workers, which use it to perform a gradient-type step to update the local version of the model. We observe that the above template is fundamentally inefficient in that too much data is unnecessarily communicated from the workers to the server, which slows down the overall system. We propose a fix based on a new update-sparsification method we develop in this work, which we suggest being used on top of existing methods. Namely, we develop a new variant of parallel block coordinate descent based on independent sparsification of the local gradient estimates before communication. We demonstrate that with only m/n blocks sent by each of n workers, where m is the total number of parameter blocks, the theoretical iteration complexity of the underlying distributed methods is essentially unaffected. As an illustration, this means that when n = 100 parallel workers are used, the communication of 99% blocks is redundant, and hence a waste of time. Our theoretical claims are supported through extensive numerical experiments which demonstrate an almost perfect match with our theory on a number of synthetic and real datasets.
Due to the high permeability of the distributed energy system under weak grid condition, the existence of line impedance reduces the voltage support capacity of the common coupling point, and the output intermittency ...
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ISBN:
(纸本)9781665499002
Due to the high permeability of the distributed energy system under weak grid condition, the existence of line impedance reduces the voltage support capacity of the common coupling point, and the output intermittency of the energy system causes power imbalance during the system operation. To solve the problems mentioned above, this paper proposes a power coordinated control method based on energy-storage parallel compensator. Considering both the state of charge (SOC) of the energy-storage battery and the device capacity limitation, the parallel compensator under proposed control method performs real-time active and reactive power compensation to the grid, effectively solving the power fluctuation of the grid-connected system and ensuring the stability of the common coupling point voltage. The overall performance of the proposed control method is illustrated with the four-quadrant operation principle, the coordination control method mechanism, and the simulation-based performance. Finally, based on RT-BOX hardware-in-the-loop experimental platform, the experimental verification of different working conditions is carried out. The experimental results prove the effectiveness and accuracy of the proposed control method.
Recognizing human emotions and responding appropriately has the potential to radically change the way we interact with technology. However, to train machines to sensibly detect and recognize human emotions, we need va...
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ISBN:
(纸本)9781450368193
Recognizing human emotions and responding appropriately has the potential to radically change the way we interact with technology. However, to train machines to sensibly detect and recognize human emotions, we need valid emotion ground truths. A fundamental challenge here is the momentary emotion elicitation and capture (MEEC) from individuals continuously and in real-time, without adversely affecting user experience. In this first edition of the one-day CHI 2020 workshop, we will (a) explore and define novel elicitation tasks (b) survey sensing and annotation techniques (c) create a taxonomy of when and where to apply an elicitation method.
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