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Quantum Computers, one fully realized, can represent an exponential boost in computing power. However, the computational power of the current quantum computers, referred to as Noisy Internediate Scale Quantum, or NISQ, is severely limited because of environmental and intrinsic noise, as well as the very low connectivity between qubits compared to their total amount. We propose a virtual quantum processor that emulates a generic hybrid quantum machine which can serve as a logical version of quantum computing hardware. This hybrid classical quantum machine powers quantum-logical computations which are substitutable by future native quantum processors., IEEE peer reviewed, published September 2021

As a side-effect of the Covid-19 pandemic, significant decreases in medical procedures for noncommunicable diseases have been observed. This calls for a decision support assisting in the analysis of opportunities to relocate procedures among hospitals in an efficient or, preferably, optimal manner. In the current paper we formulate corresponding decision problems and develop linear (mixed integer) programming models for them. Since solving mixed integer programming problems is NP-complete, we verify experimentally their usefulness using real-world data about urological procedures. We show that even for large models, with millions of variables, the problems' instances are solved in perfectly acceptable time.

Hub-and-spoke (HS) networks are cost-effective because they allow the realization of economies of density. However, the cost of point-to-point (PP) networks may be lower than that of HS networks when certain conditions, such as cargo demand, bunker price, vessel size, and the shippers’ value of time change. This study explores the factors that influence the cost-effectiveness of HS and PP networks. We developed a mixed-integer programming model that allows for bi-level optimization between shipping lines and shippers. As a case study, we applied it to Chinese and Japanese ports, with both HS and PP networks. We found that high cargo demand increases the use of PP networks while enlarging vessel size increases the use of HS networks. These findings enable us to predict the occurrence of hubbing—shifting from a PP to an HS network—and de-hubbing—shifting from an HS to a PP network.

University course timetabling problem (UCTP) includes the challenging task of generating an automated timetable for courses under resource limitations. Manual generated timetables might hold some errors and consume a long time to create feasible solutions. Thus, there is a need to find optimal and fast solutions for this problem. The difficulty of the timetabling problem is further increased when tackling faculty-related constraints, according to their requirements, preferences, and availability. Thus, student-related constraints are usually the focus of UCTP generated solutions, in which faculty constraints are limited to their teaching load or preferences. This paper proposes a multi-objective mixed-integer programming model for a preregistration UCTP, combined with faculty-related constraints. The goal is to maximize events assignments and faculty-members preferences satisfaction while balancing the university requirements. At the same time, student learning days and unassigned events are minimized. The model is tested with eight real-world instances. Computational experiments are carried out to show the efficiency of the model. The proposed method can generate optimal timetables for all problem instances that satisfy faculty constraints.

In sensor-cloud applications, a huge amount of time series are generated. Efficient similarity search approaches are necessary for processing these sensor time series data. Concerning of time series search, whole matching similarity search and subsequence similarity search are two main research focuses. In this paper, we study the whole matching similarity search problem. We propose EPLA-DSTree, which extends piecewise linear approximation on a dynamic segmentation tree index for whole matching on time series. Compared with DSTree, EPLA-DSTree improves data locality of nodes by a better time series representation. EPLA-DSTree has a tighter lower bound for nodes which leads to a better query performance. Experiments show that it has a less index building time and a better query performance. To meet the requirements of sensor-cloud applications, we present an parallel EPLA-DSTree on MapReduce, which is a popular cloud programming model.

It is important for urban traffic micro-circulation to improve the density of urban branch road networks by opening roads inside blocks. To reasonably optimize the micro-circulation road network in the open block area, a bi-level multi-objective programming model that considers traffic pollution and intersection delays was developed. In this paper, the goals of minimizing traffic pollution and total travel cost are added to the upper-level programming model and the user equilibrium assignment model with the consideration of intersection delay was presented as the lower-level programming model. A modified genetic algorithm (GA) embedded with the Frank-Wolfe algorithm was designed to solve the established model. The traffic conditions of arterial roads and micro-circulation branch roads before and after optimizing the micro-circulation block road network were compared and analyzed by a numerical example. The results demonstrated that the bi-level programming model can effectively determine the traffic direction of branch roads and the forbidden situation of intersections in the micro-circulation network. Compared with the closed block, the average saturation of the main trunk road decreased from 0.97 to 0.83 with a decline ratio of 14.43% after optimizing the micro-circulation network in the open block area; the average saturation of the secondary trunk road decreased from 0.86 to 0.77, with a decline ratio of 10.47%. The travel time cost decreased by approximately 6.55%, and the traffic pollution decreased by approximately 3.40%, which verified the optimization effect of the model and the algorithm.

In an effort towards the democratization of Robotics, this article presents a novel End-User Development framework called Robot Interfaces From Zero Experience (RIZE). The framework provides a set of useful software tools for the creation of robot-oriented software architectures and programming interfaces, as well as the modeling and execution of robot behaviors, with a specific emphasis on social behaviors. Programming interfaces built on top of RIZE enable professionals with different backgrounds and interests to design, adapt, and scale-up robotics applications. As an example of a programming interface, we present Open RIZE, which exploits an End-User Programming paradigm combining blocks, tables, and forms-filling interfaces. Unlike previous approaches, robot behavioral code generated by Open RIZE is intrinsically modular, re-usable, scalable, neutral to the employed programming language, and platform-agnostic. In the article, we present the main design guidelines and features of Open RIZE. Additionally, we perform an initial usability evaluation of the Open RIZE interface in an online workshop. Preliminary results using the System Usability Scale with 10 novice end-users indicate that Open RIZE is easy-to-use and learn.

The Internet of Things (IoT) is becoming an increasingly common paradigm. As IoT usage scenarios have increased, many challenges in IoT operating systems’ safety and adaptability have remained. According to the programming model, IoT operating systems can be categorized into three types: multithreading, event-driven, and hybrid. Different operating system models are applied in different scenarios depending on the real-time requirements or resource richness. The safety of IoT operating systems is critical; hence, formal verification is an important method of detecting potential vulnerabilities and providing safety guarantees. This paper proposes a hybrid model for an IoT operating system and employs the Event-B method for modeling and verification. We rewrite the requirements and divide the Event-Bus hybrid operating system model into eight levels for refinement. The safety and liveness properties of Event-Bus are guaranteed by generating and proving the proof obligations at each model level. A large proportion of the proof obligations (91%) are automatically proven on the Rodin platform to simplify the development process.

Lagrangian models are fundamental tools to study atmospheric transport processes and for practical applications such as dispersion modeling for anthropogenic and natural emission sources. However, conducting large-scale Lagrangian transport simulations with millions of air parcels or more can become rather numerically costly. In this study, we assessed the potential of exploiting graphics processing units (GPUs) to accelerate Lagrangian transport simulations. We ported the Massive-Parallel Trajectory Calculations (MPTRAC) model to GPUs using the open accelerator (OpenACC) programming model. The trajectory calculations conducted within the MPTRAC model were fully ported to GPUs, i.e., except for feeding in the meteorological input data and for extracting the particle output data, the code operates entirely on the GPU devices without frequent data transfers between CPU and GPU memory. Model verification, performance analyses, and scaling tests of the Message Passing Interface (MPI) – Open Multi-Processing (OpenMP) – OpenACC hybrid parallelization of MPTRAC were conducted on the Jülich Wizard for European Leadership Science (JUWELS) Booster supercomputer operated by the Jülich Supercomputing Centre, Germany. The JUWELS Booster comprises 3744 NVIDIA A100 Tensor Core GPUs, providing a peak performance of 71.0 PFlop s−1. As of June 2021, it is the most powerful supercomputer in Europe and listed among the most energy-efficient systems internationally. For large-scale simulations comprising 108 particles driven by the European Centre for Medium-Range Weather Forecasts' fifth-generation reanalysis (ERA5), the performance evaluation showed a maximum speed-up of a factor of 16 due to the utilization of GPUs compared to CPU-only runs on the JUWELS Booster. In the large-scale GPU run, about 67 % of the runtime is spent on the physics calculations, conducted on the GPUs. Another 15 % of the runtime is required for file I/O, mostly to read the large ERA5 data set from disk. Meteorological data preprocessing on the CPUs also requires about 15 % of the runtime. Although this study identified potential for further improvements of the GPU code, we consider the MPTRAC model ready for production runs on the JUWELS Booster in its present form. The GPU code provides a much faster time to solution than the CPU code, which is particularly relevant for near-real-time applications of a Lagrangian transport model.

The foundations of efficient management are laid on transport networks in various scientific and industrial fields. Nonetheless, establishing an optimum transport network design (TND) is complicated due to uncertainty in the operating environment. As a result, an uncertain network may be a more realistic representation of an actual transport network. The present study deals with an uncertain TND problem in which uncertain programming and the greedy randomized adaptive search procedure (GRASP) are used to develop an original optimization framework and propose a solution technique for obtaining cost-efficient designs. To this end, we originally develop the concept of α -shortest cycle ( α -SC) employing the pessimistic value criterion, given a user-defined predesignated confidence level α . Employing this concept and the operational law of uncertain programming, a new auxiliary chance-constrained programming model is established for the uncertain TND problem, and we prove the existence of an equivalence relation between TNDs in an uncertain network and those in an auxiliary deterministic network. Specifically, we articulate how to obtain the uncertainty distribution of the overall optimal uncertain network’s design cost. After all, the effectiveness and practical performance of the heuristic and optimization model is illustrated by adopting samples with different topology from a case study to show how our approach work in realistic networks and to highlight some of the heuristic’s features.

FPGAs are an excellent platform to implement computer vision applications, since these applications tend to offer a high level of parallelism with many data-independent operations. However, the freedom in the solution design space of FPGAs represents a problem because each solution must be individually designed, verified, and tuned. The emergence of High Level Synthesis (HLS) helps solving this problem and has allowed the implementation of open programming standards as OpenVX for computer vision applications on FPGAs, such as the HiF1ipVX library developed exclusively for Xilinx devices. Although with the HiF1ipVX library, designers can develop solutions efficiently on Xilinx, they do not have an approach to port and run their code on FPGAs from other manufacturers. This work extends the HiFlipVX capabilities in two significant ways: supporting Intel FPGA devices and enabling execution on discrete FPGA accelerators. To provide both without affecting user-facing code, the new carried out implementation combines two HLS programming models: C++, using Intel''s system of tasks, and OpenCL, which provides the CPU interoperability. Comparing with pure OpenCL implementations, this work reduces kernel dispatch resources, saving up to 24% of ALUT resources for each kernel in a graph, and improves performance 2.6 x and energy consumption 1.6 x on average for a set of representative applications, compared with state-of-the-art frameworks.

We propose a denotational semantic framework for deterministic dataflow and stream processing that encompasses a variety of existing streaming models. Our proposal is based on the idea that data streams, stream transformations, and stream-processing programs should be classified using types. The type of a data stream is captured formally by a monoid, an algebraic structure with a distinguished binary operation and a unit. The elements of a monoid model the finite fragments of a stream, the binary operation represents the concatenation of stream fragments, and the unit is the empty fragment. Stream transformations are modeled using monotone functions on streams, which we call stream transductions. These functions can be implemented using abstract machines with a potentially infinite state space, which we call stream transducers. This abstract typed framework of stream transductions and transducers can be used to (1) verify the correctness of streaming computations, that is, that an implementation adheres to the desired behavior, (2) prove the soundness of optimizing transformations, e.g. for parallelization and distribution, and (3) inform the design of programming models and query languages for stream processing. In particular, we show that several useful combinators can be supported by the full class of stream transductions and transducers: serial composition, parallel composition, and feedback composition.

In view of the limitations of storage and calculation of mass traffic data in traditional GIS platform, this paper uses efficient and scientific technical means to analyze the data, and proposes a Hadoop-based GIS mass traffic data analysis platform. The platform uses MapReduce as a distributed computing programming model to analyze massive data for urban traffic decision-making, and uses HDFS distributed file storage framework to store and manage massive traffic data at TB level or even PB level. Finally, the results are displayed by using geographic information system spatial visualization technology, and the impact of the data volume and the number of nodes in the cluster on the calculation time-consuming is analyzed and compared. The experimental results show that the use of distributed multi-node cluster can effectively improve the storage and computing efficiency of massive traffic data, and greatly accelerate the total task scheduling time.

The proliferation of on-demand internet services delivered over a network of a heterogeneous set of computing devices has created the need for high-performing dynamic systems in real-time. Services such as audio and video streaming, self-driving cars, the Internet of things (IoT), or instant communication on social networks have forced system designers to ethink the architectures and tools for implementing computer systems. Reactive programming has been advocated as a programming paradigm suitable for implementing dynamic applications with complex and heterogeneous architectural needs. However, there is no consensus on the core set of features that a reactive framework must-have. Furthermore, the current set of features proposed in reactive tools seems very restricted to cope with the actual needs for concurrency and distribution in modern systems. In this paper, several alternative semantics for distributed reactive languages are investigated, addressing complex open issues such as glitch avoidance, explicit distribution support, and constructs for explicit time management. First, we propose a reactive event-based programming language with explicit support for distribution, concurrency, and explicit time manipulation (ReactiveXD). Second, we present a reactive event-based semantic framework called Distributed Reactive Rewriting Framework (DRRF). The framework uses rewriting logic to model the components of a distributed base application, observables, and observers, and predicates supporting explicit time manipulation. Finally, to validate the proposal, the paper discusses the specification of the semantics of ReactiveXD and a scenario describing a case of intrusion detection on IoT networks, La proliferación de servicios de Internet bajo demanda entregados a través de una red de una heterogeneidad conjunto de dispositivos informáticos ha creado la necesidad de sistemas dinámicos de alto rendimiento en tiempo real. Servicios como transmisión de audio y video, automóviles autónomos, Internet de las cosas (IoT) o comunicación instantánea en las redes sociales han obligado a los diseñadores de sistemas a repensar las arquitecturas y herramientas para implementar sistemas informáticos. La programación reactiva se ha defendido como un paradigma de programación adecuado para implementando aplicaciones dinámicas con necesidades arquitectónicas complejas y heterogéneas. Sin embargo, hay No hay consenso sobre el conjunto básico de características que debe tener un marco reactivo. Además, el conjunto actual de las características propuestas en las herramientas reactivas parece muy restringido para hacer frente a las necesidades reales de concurrencia y Distribución en sistemas modernos. En este artículo, varias semánticas alternativas para lenguajes reactivos distribuidos se investigan, abordando problemas abiertos complejos como la prevención de fallas, el soporte de distribución explícito y constructos para la gestión explícita del tiempo. Primero, proponemos un lenguaje de programación reactivo basado en eventos con soporte explícito para distribución, simultaneidad y manipulación explícita del tiempo (ReactiveXD). Segundo, presentamos un marco semántico reactivo basado en eventos llamado Distributed Reactive Rewriting Framework (DRRF). El marco utiliza la lógica de reescritura para modelar los componentes de una aplicación base distribuida, observables y observadores y predicados que apoyan la manipulación explícita del tiempo. Finalmente, para validar el propuesta, el documento analiza la especificación de la semántica de ReactiveXD y un escenario que describe un caso de detección de intrusiones en redes IoT, This work was supported in part by the Escuela Colombiana de Ingeniería Julio Garavito through the Project Diseño y Construcción de Herramientas Reactivas con Aplicaciones a Middleware Distribuido Para el Procesamiento de Grandes Volumenes de Datos, and in part by the Department of Applied Mathematics and Computer Science, Universidad del Rosario., Received April 27, 2020, accepted June 16, 2020, date of publication July 20, 2020, date of current version August 17, 2020.

Residential users (RUs) are the vital component of terminal energy consumption. The development and application of integrated energy system (IES) and smart homes has promoted RUs to actively take part in the trading with multi-energy provider (MEP) for its preferential energy prices and services. This paper proposes a pricing strategy of MEP by using a Stackelberg game-based bi-level programming model. In the upper level model, the adjustment coefficient of electric power price is optimized by MEP to increase the trading probability with RUs. In the lower level model, an integrated demand response (IDR) program is proposed for RUs to optimize the flexible loads in home energy management system (HEMS). Specially, a HEMS is composed of a smart interactive terminal, a micro combined cooling, heating, and power (mCCHP) system and multi-energy loads. Case study shows that, on one hand, the energy optimization based on IDR can help RUs manage their multi-energy loads and reduce the expected energy cost. On the other hand, the proposed price strategy of MEP can increase the trading probability, which promote more RUs to trade with MEP, thus increasing the MEP's benefit by 12.29%. The research proves that the proposed strategy is a win-win strategy and it is efficient in the pre-decision-making progress for MEP in the energy trading market.

Due to the rapid development of information technology and network technology, there is a lot of data, but the phenomenon of lack of knowledge is becoming more and more serious. Data mining technology has developed vigorously in this environment, and it has shown more and more vitality. Based on Spark programming model, this paper designs the parallel extension of fuzzy c-means. In order to enhance the performance of fuzzy c-means parallel expansion, the improvement strategy of k-means during the initialization phase is borrowed, and k-means// is extended to fuzzy c-means to obtain better clustering performance. Combined with Spark’s programming model, this paper can obtain extended parallel fuzzy c-means algorithm. Several experiments on the data set of the algorithm proposed in this paper have shown good scalability and parallelism, effectively expanding fuzzy c-means clustering to distributed applications, greatly increasing the scale of the data processed by the algorithm. This improves the robustness of the algorithm and the adaptability of the algorithm to the shape and structure of the data, so that the parallel and scalable clustering algorithm can more effectively perform cluster analysis on big data. Three algorithms were simulated on MATLAB platform. We use simple data sets and complex two-dimensional data sets, and compare with the traditional fuzzy c-means algorithm and fuzzy c-means algorithm based on fuzzy entropy. Experiments show that the scalable parallel fuzzy c-means algorithm not only greatly improves the anti-noise performance, but also improves the convergence speed, and it can automatically determine the optimal number of clusters.

In order to realize the problems of non-intrusive load monitoring and decomposition (NILMD) from two aspects of load identification and load decomposition, based on the load characteristics of the database, this paper firstly analyzes and identifies the equipment composition of mixed electrical equipment group by using the load decision tree algorithm. Then, a 0–1 programming model for the equipment status identification is established, and the Particle Swarm Optimization (PSO) is used to solve the model for equipment state recognition, and the equipment operating state in the equipment group is identified. Finally, a simulation experiment is carried out for the partial data of Question A in the 6th “teddy cup” data mining challenge competition.

This paper presents a review of quantum-inspired population-based metaheuristics. Quantum-inspired algorithms were born when there were no quantum computers; they demonstrated to have interesting characteristics providing good results in classical computers. At present, when the first quantum computers are available, scientists are working to confirm the quantum supremacy in different fields. After almost 20 years that the first metaheuristic inspired in quantum phenomena was published, a large number of works have been proposed. This paper aims to look back to see which quantum-inspired metaheuristics could be translated to be used in the existing quantum computers based on the circuit model programming paradigm. Reviewed metaheuristics were classified according to their main source of inspiration; just some representative works of each classification were selected because of the vast number of existing works on each one. The analysis was done for the circuit model and metrics as width, size, and length were used to determine their viability of being implemented in a real quantum computer. Moreover, comparative results using metrics such as performance and running time for quantum-inspired metaheuristic were included.

In this study, the authors consider a project scheduling problem with a single non-renewable resource. The authors assume that the resource is released at scheduled times and specified quantities and the resource is consumed at activity completion. The activities can be processed at different modes where a mode is defined by a processing time and a resource requirement amount. The problem is to select the modes and timings of the activities so as to minimize the project completion time. The authors give a mixed integer linear programming model and discuss some variable elimination mechanisms to enhance its efficiency.

In China, the transportation capacity of high-speed railways is gradually sufficient to provide services for high-value express freight besides meeting passenger demands. However, similar as the passengers, express freight demands fluctuate and show clear peak and trough periods daily. Therefore, optimizing running numbers of express freight trains on high-speed railway by periods is quite necessary to guarantee the revenues of railway industry and to meet the various requirements of all consignees simultaneously. First, a space-period-pattern three-dimensional network with virtual arcs is built to describe the departure period selection and the stopping or skip-stopping operations. Second, by constructing the arcs' impedance function, the user equilibrium principle is introduced to optimize the express freight flow distribution for each pattern in each period. To elaborate the comprehensive goal of balancing the relationship between profits and the flow distribution, a bi-level programming model is established. The upper model addresses the railway industry's maximum profits, and the lower model addresses the minimum and similar impedance values of the final express freight flow distribution. Finally, through the use of a hybrid algorithm that combines the heuristic genetic algorithm with the Frank-Wolfe algorithm, an experimental case of 10 stations on the Beijing-Xi'an high-speed railway corridor is used to validate the study. The results show that the express freight volume is reasonably distributed to each kind of virtual arc, the impedance value of each pattern is minimized and almost equalized, and the profits of railway industry are maximized by optimizing the number and departure time of trains by each pattern in each period on the basis of meeting all the express freight demands.

This paper proposes a new multi-objective bi-level programming model for the ring road bus lines and fare design problems. The proposed model consists of two layers: the traffic management operator and travelers. In the upper level, we propose a multi-objective bus lines and fares optimization model in which the operator’s profit and travelers’ utility are set as objective functions. In the lower level, evolutionary multi agent model of travelers’ bounded rational reinforcement learning with social interaction is introduced. A solution algorithm for the multi-objective bi-level programming is developed on the basis of the equalization algorithm of OD matrix. A numerical example based on a real case was conducted to verify the proposed models and solution algorithm. The computational results indicated that travel choice models with different degrees of rationality significantly changed the optimization results of bus lines and the differentiated fares; furthermore, the multi-objective bi-level programming in this paper can generate the solution to reduce the maximum section flow, increase the profit, and reduce travelers’ generalized travel cost.

International audience; We study the interdiction of smuggling network that arranging the activities of the police in order to successfully interdict criminals in smuggling goods. This work contributes to the literature of maximum flow network interdiction problems by addressing asymmetric information, uncertain conditions, multi commodity, and with multiple sources (origins) and sinks (destinations). Information Asymmetry realistically occurs due to incomplete information of interdictor (police) and operator (smuggler) about each other's performance, which is adapted from the real-world condition. We propose two mixed-integer programming models by reformulating a Min–Max bi-level mathematical model. In the first model, the type of interdiction is discrete (zero and one), while in the second model, the interdiction is assumed continuous, meaning that the partial interdiction is possible. The asymmetry type of the smuggler's information towards the police have formulated through a linear function while the asymmetry of the police information to the smuggler is formulated using an uncertain parameter through a two-stage stochastic programming framework. To solve the first model, an innovative exact hybrid method is proposed combining of a Decomposition Method and Progressive Hedging Algorithm (DM-PHA). An augmented Karush-Kuhn-Tucker (KKT) method is also used to solve the second model. Several sensitivity analyses are then conducted, and the results demonstrate the applicability and effectiveness of the proposed models as well as the solving approach. It is also shown that the proposed models can be used as a suitable approach in uncertain environment and under asymmetric information to determine the optimal interdiction decisions of police to prevent further smuggling.

A novel approach to generic (or generalized) robot programming and a novel simplified, block-based programming environment, called &ldquo, Assembly&rdquo, are introduced. The approach leverages the newest graphical user interface automation tools and techniques to generate programs in various proprietary robot programming environments by emulating user interactions in those environments. The &ldquo, tool is used to generate robot-independent intermediary program models, which are translated into robot-specific programs using a graphical user interface automation toolchain. The generalizability of the approach to list, tree, and block-based programming is assessed using three different robot programming environments, two of which are proprietary. The results of this evaluation suggest that the proposed approach is feasible for an entire range of programming models and thus enables the generation of programs in various proprietary robot programming environments. In educational settings, the automated generation of programs fosters learning different robot programming models by example. For experts, the proposed approach provides a means for generating program (or task) templates, which can be adjusted to the needs of the application at hand on the shop floor.

This chapter describes a multi-SPMD (mSPMD) programming model and a set of software and libraries to support the mSPMD programming model. The mSPMD programming model has been proposed to realize scalable applications on huge and hierarchical systems. It has been evident that simple SPMD programs such as MPI, XMP, or hybrid programs such as OpenMP/MPI cannot exploit the postpeta- or exascale systems efficiently due to the increasing complexity of applications and systems. The mSPMD programming model has been designed to adopt multiple programming models across different architecture levels. Instead of invoking a single parallel program on millions of processor cores, multiple SPMD programs of moderate sizes can be worked together in the mSPMD programming model. As components of the mSPMD programming model, XMP has been supported. Fault-tolerance features, correctness checks, and some numerical libraries’ implementations in the mSPMD programming model have been presented.

Increases in power demand and consumption are very noticeable. This increase presents a number of challenges to the traditional grid systems. Thus, there is the need to come up with a new solution that copes with the stringent demand on energy and provides better power quality, which gives a better experience to the end users. This is how the concept of smart grids (SG) came to light. SGs have been introduced to better monitor and control the power produced and consumed. In addition to this, SGs help with reducing the electricity bill through the integration of renewable energy sources. The underlying smartness of the SGs resides in the flow of information in addition to the flow of energy. Information/data flowing implies the use of smart sensors and smart meters that sense and send data about the power produced and consumed, and the data about the environment where they are deployed. This makes SGs a direct application of IoT. In this paper, we are implementing an edge platform that is based on single-board computers (SBCs) to process data stemming from SG. The use of SBCs is driven by the energy efficiency and cost effectiveness concepts that the SG is trying to apply. The platform in question is tested against a distributed job that averages random numbers using Hadoop’s MapReduce programming model. The SBC that we are using in this implementation is the NVIDIA Jetson Developer Kit. The results of this work show that a cluster of SBCs is low-cost, easy to maintain, and simple to deploy, which makes it a great candidate for providing edge computing. Although it revealed a performance that beat the one of the remote cloud servers, it could not outperform the single-computer edge platform.

This paper deals with the problem of the design and configuration of a distribution system that supports the delivery of goods to customers using various commercial channels. In this sense, a modelled distribution system, called an omni-channel distribution system, should ensure the delivery of the same products in different ways while guaranteeing its highest efficiency. The authors propose a single-criterion mixed-integer programming model for the configuration of a complex distribution system of goods in an omni-channel environment. A minimized cost function, composed of key logistics elements including transport, warehouse location, and manipulation processes, is the objective function. The model was experimentally verified, and as a result, potential savings of around 5–8% of the omni-channel design distribution system costs versus the multi-channel distribution system costs were identified. In the paper, an extended sensitivity analysis is also performed to show how specific parameters of the model can change the final recommendation.

Unmanned Aerial Vehicles (UAV) are widely used in disaster relief and road exploration in recent years. This paper mainly studied the emergency response of UAVs after disasters. The UAV response system is mainly suitable for the distribution of necessities and road exploration after geological disasters and tsunamis in coastal areas. By analyzing the problem and making reasonable assumptions, the optimization model was established with the traffic planning theory, and MATLAB software was used to program and solve the problem. An optimal scheduling scheme was presented to solve these problems. The normalization method was used to select a highly capable UAV. Taking the minimum volume of idle space buffer material as the objective function and taking into account the constraints, such as payload of unmanned aerial vehicle, a single objective programming model was established. The results are as follows: Each International Standards Organization (ISO) cargo container has five UAVs B, one UAV C, one UAV F and one UAV H. It provides 188 days of relief requirements with ISO cargo containers’ space utilization of 71.4%. The research shows that the UAV response system has the functions of necessities distribution and road exploration after disasters, and can be used to deal with the emergency response after disasters in coastal areas, and has a wide range of applicability.

Theallreduceoperation is one of the most commonly used communication routines in distributed applications. To improve its bandwidth and to reduce network traffic, this operation can be accelerated by offloading it to network switches, that aggregate the data received from the hosts, and send them back the aggregated result. However, existing solutions provide limited customization opportunities and might provide suboptimal performance when dealing with custom operators and data types, with sparse data, or when reproducibility of the aggregation is a concern. To deal with these problems, in this work we design a flexible programmable switch by using as a building block PsPIN, a RISC-V architecture implementing the sPIN programming model. We then design, model, and analyze different algorithms for executing the aggregation on this architecture, showing performance improvements compared to state-of-the-art approaches.

In-network computing is gaining momentum as programmable switches are increasingly employed for compute acceleration. Designed for packet processing, data plane programming languages force developers to express compute in networking terms, resulting in a complex, error-prone practice. We envision the unification of switch and host programming and propose the Net Compute Language (NCL), a C/C++ extension for expressing computational kernels for switches to execute. NCL implements Compute Centric Communication (C3), our proposed programming model for INC under which, point-to-point primitives are augmented to carry out computations. We motivate our approach with real-world use cases and discuss the technical challenges for its realization.

Today, generation and transmission expansion planning (G&amp, TEP) to meet potential load growth is restricted by reliability constraints and the presence of uncertainties. This study proposes the reliability constrained planning method for integrated renewable energy sources and transmission expansion considering fault current limiter (FCL) placement and sizing and N-1 security. Moreover, an approach for dealing with uncertain events is adopted. The proposed planning model translates into a mixed-integer non-linear programming model, which is complex and not easy to solve. The problem was formulated as a tri-level problem, and a hybridization framework between meta-heuristic and mathematical optimization algorithms was introduced to avoid linearization errors and simplify the solution. For this reason, three meta-heuristic techniques were tested. The proposed methodology was conducted on the Egyptian West Delta system. The numerical results demonstrated the efficiency of integrating G&amp, TEP and FCL allocation issues in improving power system reliability. Furthermore, the effectiveness of the hybridization algorithm in solving the suggested problem was validated by comparison with other optimization algorithms.

Zero-knowledge proofs are highly flexible cryptographic protocols that are an important building block for many secure systems. Typically, these are defined with respect to statements that are formulated as arithmetic operations over a fixed finite field. This inflexibility is a disadvantage when it comes to complex programs, as some fields are more amenable to express certain operations than others. At the same time, there do not seem to be many proofs with a programming model similar to those found in modern computer architectures that perform arithmetic with 32 or 64 bit integers. In this work, we present solutions to both of these problems. First, we show how to efficiently check consistency of secret values between different instances of zero-knowledge protocols based on the commit-and-prove paradigm. This allows a protocol user to easily switch to the most efficient representation for a given task. To achieve this, we modify the extended doubly-authenticated bits (edabits) approach by Escudero et al. (Crypto 2020), originally developed for MPC, and optimize it for the zero-knowledge setting. As an application of our consistency check, we also introduce protocols for efficiently verifying truncations and comparisons of shared values both modulo a large prime p and modulo 2k. Finally, we complement our conversion protocols with new protocols for verifying arithmetic statements in Z2k. Here, we build upon recent interactive proof systems based on information-theoretic MACs and vector oblivious linear evaluation (VOLE), and show how this paradigm can be adapted to the ring setting. In particular, we show that supporting such modular operations natively in a proof system can be almost as efficient as proofs over large fields or bits, and this also easily plugs into our framework for zero-knowledge conversions.

This paper aims to improve transfer utility between bike-sharing and subway. For this paper, the transfer costs of three combined travel modes were analyzed, including “Bike-sharing + Subway”, “Walking + Subway” and “Bus + Subway”, and a transfer cost function, including time cost and expense cost, was constructed. Cluster analysis was carried out on the origin and destination of bike-sharing in the transfer-influenced area. The sum of squares of errors and the service radius were used to verify the clustering results. Then the number of alternative facilities, the location of alternative facilities and the initial number of shared bikes were preliminarily predicted. Based on the initial scheme, a bi-level programming model of facility layout and configuration in bike-sharing was established, with the goal of improving ride volume and reducing the transfer cost and facility-operation costs to optimize the initial facility-allocation scheme. Then a heuristic algorithm was used to solve the model. Finally, a typical subway station was selected as a case, and the configuration process for facilities in bike-sharing is discussed in detail in the paper. The research results of this paper may provide reference for the planning and optimization adjustments of facilities for bike-sharing.

Big Data are highly effective for systematically extracting and analyzing massive data. It can be useful to manage data proficiently over the conventional data handling approaches. Recently, several schemes have been developed for handling big datasets with several features. At the same time, feature selection (FS) methodologies intend to eliminate repetitive, noisy, and unwanted features that degrade the classifier results. Since conventional methods have failed to attain scalability under massive data, the design of new Big Data classification models is essential. In this aspect, this study focuses on the design of metaheuristic optimization based on big data classification in a MapReduce (MOBDC-MR) environment. The MOBDC-MR technique aims to choose optimal features and effectively classify big data. In addition, the MOBDC-MR technique involves the design of a binary pigeon optimization algorithm (BPOA)-based FS technique to reduce the complexity and increase the accuracy. Beetle antenna search (BAS) with long short-term memory (LSTM) model is employed for big data classification. The presented MOBDC-MR technique has been realized on Hadoop with the MapReduce programming model. The effective performance of the MOBDC-MR technique was validated using a benchmark dataset and the results were investigated under several measures. The MOBDC-MR technique demonstrated promising performance over the other existing techniques under different dimensions.

International audience; The Internet of Things (IoT) requires applications to deal with a large amount of data-streamed, processed and stored from small devices to analytical systems. Cloud computing offers a hardware solution to this issue, providing ondemand resources to process IoT data. The newer programming paradigms simplify the use of those cloud resources. The Function-as-a-Service (FaaS) and the Serverless paradigm transform the conception of microservices applications to the definition and the composition of several callable functions. Although defined as distributed architectures-mostly publicly available solutions rely on either a gateway or an internal messaging middleware. These architectures create a single point of failure in exchange for more straightforward service to service communication. In this article, we present Dyninka, a framework to rapidly prototype FaaS-based distributed dataflow applications. Its programming model gathers the definition and the composition of services within a single file using the multitier programming paradigm and compiles them into a multitude of services deployable on cloud computing infrastructure. Dyninka is built without a gateway or a messaging platform, and services communicate directly with each other or with the cloud abstracted infrastructure. As a result, we reduce the network and the computation overheads introduced by commercial FaaS frameworks such as OpenFaaS. We validate Dyninka on a Fog computing scenario with limited resources and several load profiles. For all scenarios, Dyninka shows better stability, throughput and a reduced overhead compared to OpenFaaS.

Virtual event; International audience; Making web applications run in a decentralized though collaborative way, with connectivity disruptions, is a challenging task. Opportunistic networking offers a way to be independent from a fixed infrastructure and cope with intermittent connectivity by leveraging both the mobility of nodes and their transient radio contacts. This paper presents an environment that facilitates the development of web applications deployed in opportunistic networks built out of smartphones. In order to overcome the technology hindrance regarding smartphones' ad hoc communication capabilities, our contribution externalizes opportunistic networking to a dedicated device. On top of this support for smartphones, we propose an implementation of a programming model called foglet that allows web browsers to share consistent data structures. This implementation helps achieving decentralized applications distributed across mobile web browsers without relying on any network infrastructure.

In this work, the state estimation problem of electric power systems is represented through a mathematical programming approach. Initially, a non-linear mathematical model based on the classical method of weighted least squares is proposed to solve the state estimation problem for comparative purposes. Due to the inherent limitations that this classical model presents when dealing with errors in the set of measurements, a new mathematical model is proposed that can be used within an iterative procedure to reduce the impact of measurement errors on the estimated results. Several tests on a didactic 5-bus power system and IEEE benchmark power test systems showed the effectiveness of the proposed approach which achieved better results than the proposed classical state estimation model. The non-linear programming models proposed in this paper are implemented in the mathematical modeling language AMPL. Additionally, to validate the results of the proposed methodologies, the power system operation points are compared with the results obtained using the Matpower simulation package. The results allowed concluding that the proposed mathematical models can be successfully applied to perform state estimation studies in power systems.

Based on the current background of airport management and flight-gate scheduling in China, this paper takes Shanghai Pudong International Airport’s flight number of the rising and landing aircraft in a certain day as the research object, and it establishes an uncertain FGAP (Flight-Gate Assignment Problem) multi-objective programming model under the framework of uncertainty theory. Using genetic algorithm to solve the model, the specific flight-gate assignment scheduling plan is given. The research results show that the model in this paper can effectively alleviate the problems, such as unbalanced flight-gate allocation and excessive operating pressure of a single gate, in the conventional model, and make the allocation and scheduling more reasonable and efficient. Finally, we give the future application of uncertainty theory in finance and management, as well as the prospect of combining it with symmetry in physics.

International audience; In the drive towards Exascale, the extreme heterogeneity of supercomputers at all levels places a major development burden on HPC applications. To this end, performance portable abstractions such as those advocated by Kokkos, RAJA and HPX are becoming increasingly popular. At the same time, the unprecedented scalability requirements of such heterogeneous components means higher failure rates, motivating the need for resilience in systems and applications. Unfortunately, state-of-art resilience techniques based on checkpoint/restart are lagging behind performance portability efforts: users still need to capture consistent states manually, which introduces the need for fine-tuning and customization. In this paper we aim to close this gap by introducing a set of abstractions that make it easier for the application developers to reason about resilience. To this end, we extend the existing abstractions proposed by performance portability efforts towards resilience. By marking critical data structures that need to be checkpointed, one can enable an optimized runtime to automate checkpoint-restart using high performance and scalable asynchronously techniques. We illustrate the feasibility of our proposal using a prototype that combines the Kokkos runtime (HPC performance portability), with the VELOC runtime (large-scale low overhead checkpoint-restart). Our experimental results show negligible performance overhead compared compared with a manually tuned implementation of checkpoint-restart while requiring minimal changes in the application code.

Dynamic languages like Erlang, Clojure, JavaScript, and E adopted data-race freedom by design. To enforce data-race freedom, these languages either deep copy objects during actor (thread) communication or proxy back to their owning thread. We present Dala, a simple programming model that ensures data-race freedom while supporting efficient inter-thread communication. Dala is a dynamic, concurrent, capability-based language that relies on three core capabilities: immutable values can be shared freely; isolated mutable objects can be transferred between threads but not aliased; local objects can be aliased within their owning thread but not dereferenced by other threads. Objects with capabilities can co-exist with unsafe objects, that are unchecked and may suffer data races, without compromising the safety of safe objects. We present a formal model of Dala, prove data race-freedom and state and prove a dynamic gradual guarantee. These theorems guarantee data race-freedom when using safe capabilities and show that the addition of capabilities is semantics preserving modulo permission and cast errors.

To address the challenge of performance analysis on the US DOE's forthcoming exascale supercomputers, Rice University has been extending its HPCToolkit performance tools to support measurement and analysis of GPU-accelerated applications. To help developers understand the performance of accelerated applications as a whole, HPCToolkit's measurement and analysis tools attribute metrics to calling contexts that span both CPUs and GPUs. To measure GPU-accelerated applications efficiently, HPCToolkit employs a novel wait-free data structure to coordinate monitoring and attribution of GPU performance. To help developers understand the performance of complex GPU code generated from high-level programming models, HPCToolkit constructs sophisticated approximations of call path profiles for GPU computations. To support fine-grained analysis and tuning, HPCToolkit uses PC sampling and instrumentation to measure and attribute GPU performance metrics to source lines, loops, and inlined code. To supplement fine-grained measurements, HPCToolkit can measure GPU kernel executions using hardware performance counters. To provide a view of how an execution evolves over time, HPCToolkit can collect, analyze, and visualize call path traces within and across nodes. Finally, on NVIDIA GPUs, HPCToolkit can derive and attribute a collection of useful performance metrics based on measurements using GPU PC samples. We illustrate HPCToolkit's new capabilities for analyzing GPU-accelerated applications with several codes developed as part of the Exascale Computing Project.

Hazardous chemicals are harmful to the people around them during their storage, especially when an accident occurs. The allocation and scheduling of emergency materials, therefore, is an important imperative of emergency rescue services. Due to the harmful characteristics of dangerous goods, the storage risk of hazardous chemicals in emergency networks always exists, which threatens surrounding residents. To reduce the risk of hazardous chemicals storage in terms of emergency networks, the collaborative optimization of emergency materials allocation and scheduling from the perspective of risk is proposed in the present study. The risk assessment of dangerous goods storage in different stages is developed. Minimizing the total cost and risk, a bi-level programming model of emergency material allocation and scheduling for dangerous goods storage is formulated. Then, the Karush–Kuhn–Tucker (KKT) condition is introduced to transform the proposed model, and the solution method is designed based on an augmented ε-constraint method. Finally, the computational case is provided to demonstrate the workability of the proposed model and method.

Demand response (DR) flexible loads can provide fast regulation and ancillary services as reserve capacity in power systems. This paper proposes a demand response optimization dispatch control strategy for flexible thermostatically controlled loads (TCLs) and plug-in electric vehicles (PEVs) with stochastic renewable power injection. Firstly, a chance constraint look-ahead programming model is proposed to maximize the social welfare of both units and load agents, through which the optimal power scheduling for TCL/PEV agents can be obtained. Secondly, two demand response control algorithms for TCLs and PEVs are proposed, respectively, based on the aggregate control models of the load agents. The TCLs are controlled by its temperature setpoints and PEVs are controlled by its charging power such that the DR control objective can be fulfilled. It has been shown that the proposed dispatch and control strategy can coordinate the flexible load agents and the renewable power injection. Finally, the simulation results on a modified IEEE 39 bus system demonstrate the effectiveness of the proposed demand response strategy.

Heterogeneous systems are the core architecture of most computing systems, from high-performance computing nodes to embedded devices, due to their excellent performance and energy efficiency. Efficiently programming these systems has become a major challenge due to the complexity of their architectures and the efforts required to provide them with co-execution capabilities that can fully exploit the applications. There are many proposals to simplify the programming and management of acceleration devices and multi-core CPUs. However, in many cases, portability and ease of use compromise the efficiency of different devices?even more so when co-executing. Intel oneAPI, a new and powerful standards-based unified programming model, built on top of SYCL, addresses these issues. In this paper, oneAPI is provided with co-execution strategies to run the same kernel between different devices, enabling the exploitation of static and dynamic policies. This work evaluates the performance and energy efficiency for a well-known set of regular and irregular HPC benchmarks, using two heterogeneous systems composed of an integrated GPU and CPU. Static and dynamic load balancers are integrated and evaluated, highlighting single and co-execution strategies and the most significant key points of this promising technology. Experimental results show that co-execution is worthwhile when using dynamic algorithms and improves the efficiency even further when using unified shared memory. This work was supported by the Spanish Ministry of Education (FPU16/03299 grant) and the Spanish Science and Technology Commission under contract PID2019-105660RB-C22.

International audience; Traditional data envelopment analysis (DEA) and diversification-consistent DEA, as the data-driven relative performance evaluation approaches, are widely used in the estimation of portfolio efficiency. To some extent, diversification-consistent DEA is more favored by researchers compared with traditional DEA for it deals fully with portfolio diversification. However, the existing studies assume that decision-makers can accurately estimate the statistical characteristics of portfolio returns and ignore the impact of parameter uncertainty on the portfolio efficiency and its ranking. In this paper, we construct three diversification-consistent DEA models under the mean-variance framework. We treat the expectation and covariance of portfolio return as interval values to characterize the parameter uncertainly in the proposed DEA models. And the bi-level programming models and the corresponding equivalent models are also provided to obtain the lower and upper bounds of portfolio efficiency. We select 30 American industry portfolios and perform some empirical analyses under different datasets to find out which model has better robustness in dealing with the impact of parameter uncertainty on the portfolio efficiency and its ranking. Finally, we provide some robustness tests to further verify the consistency of our findings.

To achieve high performance and high energy efficiency on near-future exascale computing systems, three key technology gaps needs to be bridged. These gaps include: energy efficiency and thermal control; extreme computation efficiency via HW acceleration and new arithmetics; methods and tools for seamless integration of reconfigurable accelerators in heterogeneous HPC multi-node platforms. TEXTAROSSA aims at tackling this gap through a co-design approach to heterogeneous HPC solutions, supported by the integration and extension of HW and SW IPs, programming models and tools derived from European research. This work is supported by the TEXTAROSSA project G.A. n.956831, as part of the EuroHPC initiative. Peer Reviewed Article signat per 51 autors/es: Giovanni Agosta, Daniele Cattaneo, William Fornaciari, Andrea Galimberti, Giuseppe Massari, Federico Reghenzani, Federico Terraneo, Davide Zoni, Carlo Brandolese (DEIB – Politecnico di Milano, Italy, name.surname@polimi.it) | Massimo Celino, Francesco Iannone, Paolo Palazzari, Giuseppe Zummo (ENEA, Italy, name.surname@enea.it) | Massimo Bernaschi, Pasqua D’Ambra (Istituto per le Applicazioni del Calcolo (IAC) - CNR, Italy, name.surname@cnr.it) | Sergio Saponara, Marco Danelutto, Massimo Torquati (University of Pisa, Italy, name.surname@unipi.it) | Marco Aldinucci, Yasir Arfat, Barbara Cantalupo, Iacopo Colonnelli, Roberto Esposito, Alberto R. Martinelli, Gianluca Mittone (University of Torino, Italy, name.surname@unito.it) | Olivier Beaumont, Berenger Bramas, Lionel Eyraud-Dubois, Brice Goglin, Abdou Guermouche, Raymond Namyst, Samuel Thibault (Inria - France, name.surname@inria.fr) | Antonio Filgueras, Miquel Vidal, Carlos Alvarez, Xavier Martorell (BSC - Spain, name.surname@bsc.es) | Ariel Oleksiak, Michal Kulczewski (PSNC, Poland, ariel@man.poznan.pl, kulka@man.poznan.pl) | Alessandro Lonardo, Piero Vicini, Francesca Lo Cicero, Francesco Simula, Andrea Biagioni, Paolo Cretaro, Ottorino Frezza, Pier Stanislao Paolucci, Matteo Turisini (INFN Sezione di Roma - Italy, name.surname@roma1.infn.it) | Francesco Giacomini (INFN CNAF - Italy, name.surname@cnaf.infn.it) | Tommaso Boccali (INFN Sezione di Pisa - Italy, name.surname@pi.infn.it) | Simone Montangero (University of Padova and INFN Sezione di Padova - Italy, name.surname@pd.infn.it) | Roberto Ammendola (INFN Sezione di Roma Tor Vergata - Italy, name.surname@roma2.infn.it)

To address the integration of software threads and hardware accelerators into the Linux Operating System (OS) programming models, an accelerator architecture is proposed, based on micro-programmable hardware system calls, which fully export these resources into the Linux OS user-space through a design-specific virtual file system. The proposed HAL-ASOS accelerator model is split into a user-defined Hardware Task and a parameterizable Hardware Kernel with three differentiated transfer channels, aiming to explore distinct BUS technology interfaces and promote the accelerator to a first-class computing unit. This paper focuses on the Hardware Kernel and mainly its microcode control unit, which will leverage the elasticity to naturally evolve with Linux OS through key differentiating capabilities of field programmable gate arrays (FPGAs) when compared to the state of the art. To comply with the evolutive nature of Linux OS, or any Hardware Task incremental features, the proposed model generates page-faults signaling runtime errors that are handled at the kernel level as part of the virtual file system runtime. To evaluate the accelerator model’s programmability and its performance, a client-side application based on the AES 128-bit algorithm was implemented. Experiments demonstrate a flexible design approach in terms of hardware and software reconfiguration and significant performance increases consistent with rising processing demands or clock design frequencies., This work has been supported by FCT-Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020.