More and more networks are becoming reconfigurable: not just the routing can be programmed, but the physical layer itself as well. Various technologies enable this programmability, ranging from optical circuit switches to beamformed wireless connections and free-space optical interconnects. Existing reconfigurable network topologies are typically hybrid in nature, consisting of static and a reconfigurable

The use of Internet of Things (IoT) is becoming increasingly common in agribusiness to increase food production capacity for the expanding global population. Recently, low-power wide-area networks (LPWANs) have been used in the development of IoT applications that require low power consumption and low data transmission rates. LoRaWAN is considered the most suitable communication network for LPWANs

Internet of Things (IoT) is a heterogeneous, mixed, and uncertain ubiquitous network, which has significantly affected the concept of wireless networking. A large number of wireless devices have connected through the IoT and shared large amounts of data. So, efficient routing and forwarding data packets from the wireless devices toward gateways, which have connected to the Internet, is one of the most

The Internet of Things is a system in which computing equipment, machinery, and digital machines are related to each other. It has a universal unique identification code (UID) and the ability to transmit data through the network without the need for human-to-human or human-to-device interaction. Augmented reality technology is a technology that ingeniously integrates virtual information with the real

EEG emotion recognition is one of the interesting and challenging tasks in the research based emotion human–computer interface system. In this paper, a multi-reservoirs feature coding continuous label fusion semi-supervised Generative Adversarial Networks (MCLFS-GAN) is proposed by using permutation phase transfer entropy as the EEG signal feature. Firstly, the obtained features are encapsulated in

With the development of microprocessor technology, massive IoT devices are deployed in smart cities which promotes numerous supervisory control and data acquisition (SCADA) systems to accomplish the key issue. The emergence of computation intensive and delay sensitive applications makes it quite a challenge for IoT devices in SCADA systems with very weak computing capacity. Vehicular edge computing

Due to the limited computing resources and battery capacity of existing mobile devices, it can not meet the requirements of low load base station group for computing capacity and delay, and the emergence of mobile edge computing (MEC) technology provides the possibility for it. Therefore, a distributed task unloading strategy to low load base station group under MEC environment is proposed. Firstly

The limited power source of sensors is the main constraint of Wireless Sensor Networks (WSNs); therefore, some energy management techniques are required. Network coding and topology control techniques have received extensive attention to decrease energy consumption and improve network performance. Although, combining these two techniques in WSNs can reduce energy consumption efficiently, their main

Detecting cyber threats has been an on-going research endeavor. In this era, Advanced Persistent Threats (APTs) can incur significant costs for organizations and businesses. The ultimate goal of cybersecurity is to thwart attackers from achieving their malicious intent, whether it is credential stealing, infrastructure takeover, or program sabotage. Every cyber attack goes through several stages before

Cognitive radio network has been proposed as a promising technology to satisfy the manifold requirements of future generation (5G) wireless system by intelligently accessing the underutilized channel of a primary user. However, due to the heterogeneity in channel propagation characteristics, intermittent availability of licensed channel, recurrent hand-offs, and protection to primary users, finding

Collaboration is a keystone of defense in the field of cybersecurity. A collaborative detection system allows multiple collaborators or service providers to share their security-incident-response data, in order to effectively identify and isolate stealthy malicious actors who hide their traffic under the umbrella of legitimate Internet data transmissions. The fundamental challenge in the design of

Conformance checking enables organizations to automatically assess whether their business processes are executed according to their specification. State-of-the-art conformance checking algorithms perform this task by establishing alignments between behaviour recorded by IT systems to a process model capturing desired behaviour. While such alignments clearly highlight conformance issues, a major downside

Although the amount of RDF data has been steadily increasing over the years, the majority of information on the Web is still residing in other formats, and is often not accessible to Semantic Web services. A lot of this data is available through APIs serving JSON documents. In this work we propose a way of extending SPARQL with the option to consume JSON APIs and integrate this information into SPARQL

Knowledge-based applications like recommender systems in social networks are powered by complex network of social discussions and user connections. Short text microblog platforms like Twitter are powerful in this aspect due to their real-time content dissemination as well as having a complex mesh of user connections. For example, users on Twitter tend to consume certain content to a greater or less

We consider the parameterized complexity of the problem of tracking shortest s-t paths in graphs, motivated by applications in security and wireless networks. Given an undirected and unweighted graph with a source s and a destination t, Tracking Shortest Paths asks if there exists a k-sized subset of vertices (referred to as tracking set) that intersects each shortest s-t path in a distinct set of

The maximum independent set problem is known to be NP-hard in the class of subcubic graphs, i.e. graphs of vertex degree at most 3. We study complexity of the problem on hereditary subclasses of subcubic graphs. Each such subclass can be described by means of forbidden induced subgraphs. In case of finitely many forbidden induced subgraphs a necessary condition for polynomial-time solvability of the

We study the worst-case behavior of Turán-like bounds for unweighted and weighted independent sets in bounded-degree graphs. In particular, we revisit a randomized approach of Boppana that forms a simple 1-round distributed algorithm, as well as a streaming algorithm and a preemptive online algorithm. We show that it gives a tight (Δ+1)/2-approximation in unweighted graphs of maximum degree Δ, which

In the fast evacuation problem, we study the path planning problem for two robots who want to minimize the worst-case evacuation time on the unit disk, that is, the time till both of them evacuate. The robots are initially placed at the center of the disk. In order to evacuate, they need to reach an unknown point, the exit, on the boundary of the disk. Once one of the robots finds the exit, it will

It is known for some time that a random graph G(n,p) contains w.h.p. a Hamiltonian cycle if p is larger than the critical value pcrit=(log⁡n+log⁡log⁡n+ωn)/n. The determination of a concrete Hamiltonian cycle for G(n,p) is a nontrivial task, even when p is much larger than pcrit. In this paper we consider random graphs G(n,p) with p in Ω˜(1/n), where Ω˜ hides poly-logarithmic factors in n. For this

The matching preclusion number of a graph, introduced in [2] as a fault analysis, is the minimum number of edges whose deletion leaves a resulting graph that has neither perfect matchings nor almost perfect matchings. As a generalization, Liu and Liu [14] recently introduced the concept of fractional matching preclusion number. The fractional matching preclusion number of graph is the minimum number

A caterpillar is either a K2 or a tree on at least 3 vertices such that deleting its leaves we obtain a path of order at least 1. Given a simple undirected graph G=(V,E), a caterpillar factor of G is a set of caterpillar subgraphs of G such that each vertex v∈V belongs to exactly one of them. A caterpillar factor F is internally even if every vertex of degree degF(v)≥2 has an even degree; F is odd

We introduce and study a new search-type problem with (n+1)-robots on a disk. The searchers (robots) all start from the center of the disk, have unit speed, and can communicate wirelessly. The goal is for a distinguished robot (the queen) to reach and evacuate from an exit that is hidden on the perimeter of the disk in as little time as possible. The remaining n robots (servants) are there to facilitate

The Almost Induced Matching problem asks whether we can delete at most k vertices from the input graph such that each vertex in the remaining graph has a degree exactly one. This paper studies parameterized algorithms for this problem by taking the size k of the deletion set as the parameter. We give a 7k-vertex kernel and an O⁎(1.7485k)-time and polynomial-space algorithm, both of which are the best-known

We establish new results on the curve complexity of k-colored point-set embeddings when k=3. We show that there exist 3-colored caterpillars with only three independent edges whose 3-colored point-set embeddings may require Ω(n13) bends on Ω(n23) edges. This settles an open problem by Badent et al. [5] about the curve complexity of point set embeddings of k-colored trees and it extends a lower bound

We study a Curry style type assignment system for untyped λ-calculi with effects, based on Moggi's monadic approach. Moving from the abstract definition of monads, we introduce a version of the call-by-value computational λ-calculus based on Wadler's variant, without let, and with unit and bind operators. We define a notion of reduction for the calculus and prove it confluent. We then introduce an

Prior-free auctions are robust auctions that assume no distribution over bidders' valuations and provide worst-case (input-by-input) approximation guarantees. In contrast to previous work on this topic, we pursue good prior-free auctions with non-identical bidders. Prior-free auctions can approximate meaningful benchmarks for non-identical bidders only when sufficient qualitative information about

We consider the distributed setting of N autonomous mobile robots that operate in Look-Compute-Move (LCM) cycles and communicate with other robots using colored lights following the robots with lights model. We assume obstructed visibility under which a robot cannot see another robot if a third robot is positioned between them on the straight line connecting them. We study the fundamental Complete

The Lyndon factorization of a word has been largely studied and recently variants of it have been introduced and investigated with different motivations. In particular, the canonical inverse Lyndon factorization ICFL(w) of a word w, introduced in [1], maintains the main properties of the Lyndon factorization since it can be computed in linear time and it is uniquely determined. In this paper we investigate

The pebble tree automaton and the pebble tree transducer are enhanced by additionally allowing an unbounded number of “invisible” pebbles (as opposed to the usual “visible” ones). The resulting pebble tree automata recognize the regular tree languages (i.e., can validate all generalized DTD's) and hence can find all matches of MSO definable patterns. Moreover, when viewed as a navigational device,

We introduce the notions of topological entropy of a formal language and of a topological automaton. We show that the entropy function is surjective and bound the entropy of languages accepted by deterministic ε-free push-down automata with an arbitrary amount of stacks.

The exchanged hypercube, denoted by EH(s,t) where s,t≥1 are two positive integers, is a variant of hypercube network. The reliability and diagnosis capability of exchanged hypercubes have been investigated in this paper. First, we studied the h-extra connectivity and h-extra edge connectivity of EH(s,t) which can reflect its fault tolerance ability; Second, we studied the h-resticted vertex diagnosability

Given an undirected graph G with n vertices, the independent feedback vertex set problem is to find a vertex subset F of G with the minimum number of vertices such that F is both an independent set and a feedback vertex set of G, if it exists. This problem is known to be NP-hard for bipartite planar graphs of maximum degree four. In this paper, we study the approximability of the problem. We first

The number of palindromic factors of a given finite word is bounded above by its length increased by 1. The difference between this upper bound and the actual number of palindromic factors of a given word is called the palindromic defect (or only defect) of a given word (by definition, the defect is always nonnegative). Though the definition of defect fundamentally relies on finiteness of a given word

A subset D⊆V of a graph G=(V,E) is called a global total k-dominating set of G if D is a total k-dominating set of both G and the complement G‾ of G. The Minimum Global Total k-Domination problem is to find a global total k-dominating set of minimum cardinality of the input graph G and Decide Global Total k-Domination problem is the decision version of Minimum Global Total k-Domination problem. The

We present an algorithm to color a graph G with no triangle and no induced 7-vertex path (i.e., a {P7,C3}-free graph), where every vertex is assigned a list of possible colors which is a subset of {1,2,3}. While this is a special case of the problem solved in Bonomo et al. (2018) [1], that does not require the absence of triangles, the algorithm here is both faster and conceptually simpler. The complexity

Consider a graph G and its connected subgraph T. The T-structure connectivity κ(G;T) of G is the cardinality of a minimum set of subgraphs in G, whose removal disconnects G and each element in the set is isomorphic to T. The T-substructure connectivity κs(G;T) of G is the cardinality of a minimum set of subgraphs in G, whose removal disconnects G and each element in the set is isomorphic to a connected

Inspired from spiking and dynamic mechanisms of neurons, dynamic threshold neural P systems (DTNP systems) have been developed and their computational completeness as number-generating/accepting devices and function computing devices has been investigated. However, a universality result of DTNP systems as language generators has not been established so far. This paper discusses computational power

It was recently shown that anti-unification over an equational theory consisting of only unit equations (more than one) is nullary. Such pure theories are artificial and are of little effect on practical aspects of anti-unification. In this work, we extend these nullarity results to the theory of semirings, a heavily studied theory with many practical applications. Furthermore, our argument holds over

Relational structures based on acyclic relations can successfully model fundamental aspects of concurrent systems behaviour. Examples include Elementary Net systems and Mazurkiewicz traces. There are however cases where more general relational structures are needed. In this paper, we present a general model of relational structures which can be used for a broad class of concurrent behaviours. We demonstrate

The Max k-Uncut problem arose from the study of homophily of large-scale networks. Given an n-vertex undirected graph G=(V,E) with nonnegative weights defined on edges and a positive integer k, the Max k-Uncut problem asks to find a partition {V1,V2,⋯,Vk} of V such that the total weight of edges that are not cut is maximized. This problem is the complement of the classic Min k-Cut problem, and was

The Arbitrary Pattern Formation problem asks for a distributed algorithm that moves a set of autonomous mobile robots to form any arbitrary pattern given as input. The robots are assumed to be autonomous, anonymous and identical. They operate in Look-Compute-Move cycles under an asynchronous scheduler. The robots do not have access to any global coordinate system. The movement of the robots is assumed

The quality of a location-based social network (LBSN) is mainly related to the granularity of information on the users' location. When LBSN is built using stay points, it presents much more information since GPS logs convey more users' mobility information. However, the main challenge in building LBSN using stay points is to define local-vertices. This problem is known as local-entity resolution. This

We explore the relationship between propagation tree decompositions of a graph of a given size and the OS-sets of the same size, showing that each can generate the other. We give a short constructive proof that the OS-sets are in bijective correspondence with a subset of the propagation tree decompositions.

We study the task of gathering k energy-constrained mobile agents in an undirected edge-weighted graph. Each agent is initially placed on an arbitrary node and has a limited amount of energy, which constrains the distance it can move. Since this may render gathering at a single point impossible, we study three variants of near-gathering: The goal is to move the agents into a configuration that minimizes

Due to the explosive growth in trajectory data with multi-semantic labels, mining hotspots based on extracted sequential patterns from multi-semantic trajectories are an emerging need in various applications of crowd behavior analysis, such as location-based advertising, business location, and urban planning. However, most existing regional pattern mining methods only focus on temporal continuity,

Large-scale knowledge graphs such as Wikidata and DBpedia have become a powerful asset for semantic search and question answering. However, most of the knowledge graph construction works focus on organizing and discovering textual knowledge in a structured representation, while paying little attention to the proliferation of visual resources on the Web. To consolidate this recent trend, in this paper

Typical speech separation systems usually operate in the time-frequency (T-F) domain by enhancing the magnitude response and leaving the phase response unaltered. Recent studies, however, suggest that phase is important for perceptual quality, leading many researchers to consider magnitude and phase spectrum enhancements. The complex-valued Fourier spectrum and real-valued shifted real spectrum (SRS)

Masses of large-scale knowledge graphs on various domains have sprung up in recent years. They are no longer able to be managed on a single machine. The distributed RDF systems intervene in the scalability issue using partitioning techniques. However, most of these systems are unaware of query workload and employ static partitioning. As diverse and dynamic workloads keep emerging in the knowledge graph

Concepts and instances are important parts in knowledge graphs, but most knowledge graph embedding models treat them as entities equally, that leads to inaccurate embeddings of concepts and instances. Aiming to solve this problem, we propose a novel knowledge graph embedding model called JECI++ to jointly embed concepts and instances. First, JECI++ simplifies hierarchical concepts based on subClassOf

Prediction of the likely evolution of traffic scenes is a challenging task because of high uncertainties from sensing technology and the dynamic environment. It leads to failure of motion planning for intelligent agents like autonomous vehicles. In this paper, we propose a fluid-inspired model to estimate collision risk in road scenes. Multi-object states are detected and tracked, and then a stable

Digital try-on systems for e-commerce have the potential to change people's lives and provide notable economic benefits. However, their development is limited by practical constraints, such as accurate sizing of the body and realism of demonstrations. We enumerate three open challenges remaining for a complete and easy-to-use try-on system that recent advances in machine learning make increasingly

René Schumann1*, Michael Brand2 and Khoa Nguyen1 1 HES-SO Valais Wallis, SiLab, Rue de Technpole 3, 3960 Sierre, 3960 Sierre, Switzerland; 2 OFFIS - Institut für Informatik, Escherweg 2, 26121 Oldenburg, Switzerland. Correspondence: René Schumann (rene.schumann@hevs.ch) Dear readers, Fig. 1 (abstract P1). General Procedure for Protocol Fuzzing.Full size image Fig. 1 (abstract P4). Developed sensor

Unlocking and managing flexibility is an important contribution to the integration of renewable energy and an efficient and resilient operation of the power system. In this paper, we discuss how the potential of a fleet of battery-electric transportation vehicles can be used to provide frequency containment reserve. To this end, we first examine the use case in detail and then present the system designed

In the context of a pilot project, the Lugaggia Innovation Community (LIC), we address the problem of non-intrusive load monitoring for the purpose of demand side management on low voltage grids in presence of distributed power generation (photovoltaic). From the power readings of smart meters, we estimate the photovoltaic production and detect the activation of major loads (heatpumps and domestic

The transition of the power grid requires new technologies and methodologies, which can only be developed and tested in simulations. Especially larger simulation setups with many levels of detail can become quite slow. Therefore, the number of possible simulation evaluations decreases. One solution to overcome this issue is to use surrogate models, i. e., data-driven approximations of (sub)systems

In this paper, a thorough analysis of quantification of the heating appliances’ flexibility provided by 200 households located in the Sion area (Switzerland) is presented. An extended evaluation of the available flexibility throughout the year as well as a correlation analysis between the outside temperature and flexibility is performed. The influence of pooling households in the prediction process

To face the challenges of climate change, the integration of renewable energy sources in the energy-intensive heating sector is a crucial aspect of emission reduction. For an efficient operation of coupling devices such as heat pumps with intermittent sources of renewable energy, accurate heat load forecasts need to be developed and embedded into an operation strategy to enable further decarbonisation

Heat pumps embody solutions that heat or cool buildings effectively and sustainably, with zero emissions at the place of installation. As they pose significant load on the power grid, knowledge on their existence is crucial for grid operators, e.g., to forecast load and to plan grid operation. Further details, like the thermal reservoir (ground or air source) or the age of a heat pump installation

The development of efficient electric vehicle (EV) charging infrastructure requires modelling of consumer demand at an appropriate level of detail. Since only limited information about real customers is available, most simulations employ a stochastic approach by combining known or estimated business features (e.g. arrival and departure time, requested amount of energy) with random variations. However