LOCATION-BASED SERVICES (LBSS) ASSUME THAT USERS ARE WILLING TO RELEASE TRUSTWORTHY AND USEFUL DETAILS ABOUT THEIR WHEREABOUTS. HOWEVER, MANY LOCATION PRIVACY CONCERNS HAVE ARISEN. FOR LOCATION PRIVACY PROTECTION, SEVERAL ALGORITHMS BUILD A CLOAKING REGION TO HIDE A USER?S LOCATION. HOWEVER, MANY APPLICATIONS MAY NOT OPERATE ADEQUATELY ON CLOAKED LOCATIONS. FOR EXAMPLE, A TRADITIONAL DISTANCE BOUNDING PROTOCOL (DBP)?WHICH IS RUN BY TWO NODES CALLED THE PROVER AND THE VERIFIER?MAY CONCLUDE AN UNTIGHT AND USELESS DISTANCE BETWEEN THESE TWO ENTITIES. AN LBS (VERIFIER) MAY USE THIS DISTANCE AS A METRIC OF USEFULNESS AND TRUSTWORTHINESS OF THE LOCATION CLAIMED BY THE USER (PROVER). HOWEVER, WE SHOW THAT IF A TIGHT DISTANCE IS DESIRED, TRADITIONAL DBP CAN REFINE A USER?S CLOAKED LOCATION AND COMPROMISE ITS LOCATION PRIVACY. TO FIND A PROPER BALANCE, WE PROPOSE A LOCATION-PRIVACY-AWARE DBP PROTOCOL. OUR SOLUTION CONSISTS OF ADDING SOME SMALL DELAYS BEFORE SUBMITTING ANY USER?S RESPONSE. WE SHOW THAT SEVERAL ISSUES ARISE WHEN A CERTAIN DELAY IS CHOSEN, AND WE PROPOSE SOME SOLUTIONS. THE EFFECTIVENESS OF OUR TECHNIQUES IN BALANCING LOCATION REFINEMENT AND UTILITY IS DEMONSTRATED THROUGH SIMULATION.

THE ADVANCE OF TECHNOLOGIES IN SEVERAL AREAS HAS ALLOWED THE DEVELOPMENT OF SMART CITY APPLICATIONS, WHICH CAN IMPROVE THE WAY OF LIFE IN MODERN CITIES. WHEN EMPLOYING VISUAL SENSORS IN THAT SCENARIO, STILL IMAGES AND VIDEO STREAMS MAY BE RETRIEVED FROM MONITORED AREAS, POTENTIALLY PROVIDING VALUABLE DATA FOR MANY APPLICATIONS. ACTUALLY, VISUAL SENSOR NETWORKS MAY NEED TO BE HIGHLY DYNAMIC, REFLECTING THE CHANGING OF PARAMETERS IN SMART CITIES. IN THIS CONTEXT, CHARACTERISTICS OF VISUAL SENSORS AND CONDITIONS OF THE MONITORED ENVIRONMENT, AS WELL AS THE STATUS OF OTHER CONCURRENT MONITORING SYSTEMS, MAY AFFECT HOW VISUAL SENSORS COLLECT, ENCODE AND TRANSMIT INFORMATION. THIS PAPER PROPOSES A FUZZY-BASED APPROACH TO DYNAMICALLY CONFIGURE THE WAY VISUAL SENSORS WILL OPERATE CONCERNING SENSING, CODING AND TRANSMISSION PATTERNS, EXPLOITING DIFFERENT TYPES OF REFERENCE PARAMETERS. THIS INNOVATIVE APPROACH CAN BE CONSIDERED AS THE BASIS FOR MULTI-SYSTEMS SMART CITY APPLICATIONS BASED ON VISUAL MONITORING, POTENTIALLY BRINGING SIGNIFICANT RESULTS FOR THIS RESEARCH FIELD.

IMAGE INTERLEAVING HAS PROVEN TO BE AN EFFECTIVE SOLUTION TO PROVIDE THE ROBUSTNESS OF IMAGE COMMUNICATION SYSTEMS WHEN RESOURCE LIMITATIONS MAKE RELIABLE PROTOCOLS UNSUITABLE (E.G., IN WIRELESS CAMERA SENSOR NETWORKS); HOWEVER, THE SEARCH FOR OPTIMAL INTERLEAVING PATTERNS IS SCARCELY TACKLED IN THE LITERATURE. IN 2008, ROMBAUT ET AL. PRESENTED AN INTERESTING APPROACH INTRODUCING A PACKETIZATION MASK GENERATOR BASED IN SIMULATED ANNEALING (SA), INCLUDING A COST FUNCTION, WHICH ALLOWS ASSESSING THE SUITABILITY OF A PACKETIZATION PATTERN, AVOIDING EXTENSIVE SIMULATIONS. IN THIS WORK, WE PRESENT A COMPLEMENTARY STUDY ABOUT THE NON-TRIVIAL PROBLEM OF GENERATING OPTIMAL PACKETIZATION PATTERNS. WE PROPOSE A GENETIC ALGORITHM, AS AN ALTERNATIVE TO THE CITED WORK, ADOPTING THE MENTIONED COST FUNCTION, THEN COMPARING IT TO THE SA APPROACH AND A TORUS AUTOMORPHISM INTERLEAVER. IN ADDITION, WE ENGAGE THE VALIDATION OF THE COST FUNCTION AND PROVIDE RESULTS ATTEMPTING TO CONCLUDE ABOUT ITS IMPLICATION IN THE QUALITY OF RECONSTRUCTED IMAGES. SEVERAL SCENARIOS BASED ON VISUAL SENSOR NETWORKS APPLICATIONS WERE TESTED IN A COMPUTER APPLICATION. RESULTS IN TERMS OF THE SELECTED COST FUNCTION AND IMAGE QUALITY METRIC PSNR SHOW THAT OUR ALGORITHM PRESENTS SIMILAR RESULTS TO THE OTHER APPROACHES. FINALLY, WE DISCUSS THE OBTAINED RESULTS AND COMMENT ABOUT OPEN RESEARCH CHALLENGES.

IN HARD ROCK MINE OPERATIONS, THE GRAVITATIONAL SEGREGATION OF ORE PARTICLES WITHIN A STOCKPILE CREATES A HIGH VARIATION OF PARTICLE SIZE. THIS ISSUE HAMPERS PRODUCTIVITY IN THE COMMINUTION PROCESS AND HAS A DIRECT EFFECT ON THE DAILY OUTPUT OF PRODUCED MINERALS FROM THE MINE. DOZER OPERATION CAN BE FACILITATED TO MIX THE STOCKPILE MATERIALS FOR MAINTAINING A MORE HOMOGENEOUS PARTICLE SIZE DISTRIBUTION, HOWEVER THIS CAN LEAD TO POTENTIALLY HAZARDOUS SITUATIONS FOR THE MACHINE AND OPERATOR DUE TO THE DYNAMIC NATURE OF THE STOCKPILE. THE USE OF AUTONOMOUS BULLDOZERS IS A NEW TREND FOR MINE EQUIPMENT OPERATION, IMPROVING THE SAFETY OF DOZER OPERATORS WORKING IN THE STOCKPILE BY REMOVING THEM FROM THE MACHINE ALTOGETHER. THIS PAPER DESCRIBES PATH-PLANNING STRATEGY FOR AUTONOMOUS DOZERS TO OPERATE OVER A STOCKPILE WITHIN A PREDEFINED SAFE REGION. FOR THIS PURPOSE, A STOCKPILE MODEL IS DEVELOPED, WHERE LEVEL AND PARTICLE SIZE PROPERTIES ARE USED TO DESCRIBE THE STOCKPILE IN TERMS OF SECTORS. THIS INFORMATION IS THEN USED TO COMMAND THE OPERATION OF AN AUTONOMOUS DOZER OVER THE STOCKPILE BASED ON CURRENT SAG MILL FEED STATE. SIMULATION RESULTS PREDICT ACCEPTABLE BEHAVIOR, PROVIDED THAT SENSOR INFORMATION PROVIDES ENOUGH ACCURACY TO SPECIFY SAFETY AND PERFORMANCE CONSTRAINS.

IN THIS PAPER, WE DESIGN AND EVALUATE A CONTROL SYSTEM WHICH, BY USING AS INPUT RSSI MEASURES, ALLOWS ANTICIPATORY MOVEMENTS OF ROBOTIC ARMS DECREASING IDLE TIMES AT THE CIMUBB LABORATORY. CLASSICAL LOG-NORMAL MODEL, WHICH RELATES THE STRENGTH OF A SIGNAL RECEIVED BY A NODE WITH THE DISTANCE AT WHICH THE SENDER OF THE SIGNAL IS, WAS ADOPTED. THE HIDDEN STATE OF THE SYSTEM IS DETERMINED BY THE EXTENDED KALMAN FILTER WHICH ALLOWS US TO ESTIMATE THE DISTANCE AND THE SPEED OF PALLETS MOVING OVER A CLOSED-LOOP CONVEYOR BELT. FROM THESE ESTIMATES, REMAINING TIME IN WHICH THE PALLET WILL GET TO A STOPPING POINT NEAR THE ROBOT IS DETERMINED. THIS INFORMATION IS FINALLY PROCESSED BY A CONTROLLER TO DETERMINE THE INSTANT AT WHICH THE ROBOT MUST OPERATE AND HANDLE THE PALLET. BOTH, A PROPORTIONAL-INTEGRAL AND A FUZZY CONTROLLER, WERE IMPLEMENTED AND EVALUATED. RESULTS SHOW THE FEASIBILITY OF USING WIRELESS SIGNALS TO ACCOMPLISH THE DESCRIBED GOAL, WITH SOME PRACTICAL RESTRICTIONS.

THIS WORK STUDIED DIFFERENT DIGITAL EMBEDDED PLATFORMS WHICH CAN BE PROGRAMMED USING ARDUINO IDE SOFTWARE AND WHICH CAN BE USED FOR DIGITAL CONTROL AND DATA ACQUISITION APPLICATIONS. SPECIFICALLY THREE KIND OF ARDUINO BOARD (ARDUINO UNO, ARDUINO MEGA Y ARDUINO DUE) AND TWO ESP BASED BOARD (ESP8622 AND ESP32) ARE EVALUATED AND COMPARED. THE COMPARISON IS BASED ON THE EXECUTION TIME OF MATHEMATICAL OPERATIONS AND A FUNCTION REQUIRED FOR DATA ACQUISITION OR DIGITAL CONTROL AND INCLUDES (I) DIGITAL PORTS WRITING, (II) ANALOG SIGNAL ACQUISITION, (III) EXECUTION OF MATHEMATIC OPERATION IN INTEGER AND FLOAT FORMAT, AND (IV) THE EXECUTION OF THE DATA PROCESSING CODE. THE EXECUTION TIME IS MEASURED BY USING A METHODOLOGY WHICH IS SIMPLE TO IMPLEMENT FOR ANY OTHER DIGITAL DEVICE. BECAUSE OF EACH PLATFORM USES ITS OWN ARDUINO DUE LIBRARY TO GENERATE THE ASSEMBLY CODE FOR ITS OWN MICROCONTROLLER, THE INSTRUCTIONS ADOPTED FOR BOTH GENERATING THE ACTIONS TO MEASURE AND GENERATING THE TESTING SIGNALS ARE WRITTEN USING ARDUINO IDE COMMANDS AND USING INSTRUCTIONS THAT ANY ENTRY-LEVEL USER MAY ADOPT. IN CONCLUSION, FROM THE EXPERIMENTAL RESULTS IT IS OBSERVED THE HIGH DIFFERENCE IN THE EXECUTION TIME OF THE DIFFERENT PLATFORMS, ESPECIALLY BETWEEN ESPX BOARDS AND ARDUINO BOARDS.

WIRELESS COMMUNICATION SYSTEMS CAN BE USED TO SUPPORT A LOT OF INDUSTRIAL APPLICATIONS AND MUCH EFFORT HAS BEEN DONE TO DESIGN SOLUTIONS FOR THIS SCENARIO. ACTUALLY, AN IMPORTANT ISSUE WHEN DESIGNING SUCH SOLUTIONS IS THE PERFORMANCE EVALUATION, WHICH REQUIRES PROPER RESOURCES FOR ACCURATE RESULTS. THIS PAPER THEN PROPOSES AN EXPERIMENTAL PLATFORM WHERE THE DEVICES COMMUNICATE VIA WIRELESS AND WIRE NETWORK. THE RESULTS SHOW IN TERM OF PERFORMANCE THE GAP BETWEEN THESE TWO NETWORKS.

IN THIS ARTICLE, WE PRESENT THE DEVELOPMENT OF A SIMPLE MULTIAGENT-BASED SYSTEM FOR THE CONTROL OF A FLEXIBLE MANUFACTURING SYSTEM. WE FOLLOWED THE STAGES OF A METHODOLOGY SPECIALLY CONCEIVED FOR THE DEVELOPMENT OF AGENT-BASED SYSTEM, WHICH IS AN INTEGRATION OF THE CLASSICAL METHODOLOGY FOR AGENT-ORIENTED ANALYSIS AND DESIGN GAIA, AND AUML (AGENT-UNIFIED MODELING LANGUAGE). WE ADOPTED AS STUDY CASE THE CIMUBB LABORATORY AT THE UNIVERSITY OF BIO-BIO, WHICH HAS A FLEXIBLE MANUFACTURING SYSTEM INCLUDING THREE FLEXIBLE MANUFACTURING CELLS INTERCONNECTED BY A CONVEYOR BELT. IN THE ANALYSIS STAGE, WE IDENTIFIED ROLES INVOLVED, AND WE DESIGN MODELS REPRESENTING ROLES AND PROTOCOLS. IN THE DESIGN STAGE, WE APPLIED GAIA AGENT, SERVICES, AND ACQUAINTANCE MODELS FROM GAIA, AND WE COMPLEMENTED WITH AUML AS THE ADOPTED METHODOLOGY SUGGESTS. WITH THE DEVELOPED MODELS, WE CONSTRUCTED A FULLY FUNCTIONAL SYSTEM WHERE EACH AGENT WAS BUILT AS AN INDEPENDENT PROCESS TREE. AGENTS COMMUNICATE BY PASSING MESSAGES THROUGH THE ETHERNET NETWORK WITH SOCKET INTERFACES. VARIOUS TESTS EXECUTED IN OUR LABORATORY SCALE MANUFACTURING SYSTEM SHOW THE EFFECTIVENESS OF OUR IMPLEMENTATION. COPYRIGHT © 2015 JOHN WILEY & SONS, LTD.

IN THIS PAPER, WE PROPOSE A CONTROL MODEL BASED ON NCS THEORY TO SOLVE THE VEHICLE-FOLLOWING PROBLEM, WHICH PRESENTS BOTH ISSUES: THE DIFFICULTY IN THE IDENTIFICATION PROCESS AND A LOSSY NETWORK. TO DEAL WITH NETWORK LOSSES, WE USE A MODE DEPENDENT MARKOV JUMP LINEAR FILTER COUPLED WITH A STATEFEEDBACK CONTROLLER. TO HANDLE PARAMETER UNCERTAINTY, A POLYTOPIC REPRESENTATION OF THE CAR MODEL IS PRESENTED. THE PERFORMANCE TO BE OPTIMIZED IS A GUARANTEED COST OF THE H ? NORM. THE PROPOSAL IS COMPARED WITH A FULL-ORDER MODE DEPENDENT H ? CONTROLLER (ALSO A MARKOVIAN CONTROLLER), WHICH IS OPTIMAL FOR THE NETWORK LOSSES BUT CANNOT HANDLE THE POLYTOPIC UNCERTAINTIES. RESULTS SHOW THAT OUR APPROACH OUTPERFORMS THE CONTROLLERS THAT ARE NOT DESIGNED TO COPE WITH PARAMETER UNCERTAINTIES.

CAMERA-ENABLED SENSORS DEPLOYED FOR VISUAL MONITORING WILL COVER A REGION OF THE TARGET FIELD, PROVIDING INFORMATION FOR MANY INNOVATIVE APPLICATIONS BASED ON WIRELESS SENSING. ACTUALLY, SOME AREAS OF THE MONITORED FIELD MAY HAVE MORE RELEVANCE THAN OTHERS, ACCORDING TO THE CHARACTERISTICS OF THE APPLICATIONS, WHICH MAY INDICATE THAT SUCH AREAS NEED BETTER COVERAGE TO AVOID BLIND SPOTS AND ACHIEVE HIGHER VISUAL REDUNDANCY. IN ORDER TO PROVIDE A METRIC TO ASSESS HOW WELL RELEVANT AREAS ARE BEING COVERED, THIS PAPER PROPOSES AN AVAILABILITY METRIC WHICH ASSOCIATES COVERAGE TO THE RELEVANCE OF AREAS, WHICH MAY BE USEFUL WHEN ASSESSING MONITORING AVAILABILITY. MOREOVER, A GREEDY ALGORITHM IS ALSO PROPOSED TO COMPUTE SENSING ORIENTATIONS FOR ALL VISUAL SENSORS, AIMING AT THE ENHANCEMENT OF VISUAL COVERAGE OVER THE MOST RELEVANT AREAS. WITH SUCH PROPOSALS, IT IS POSSIBLE TO INITIALLY ADDRESS THE PARTICULAR PROBLEM OF VISUAL COVERAGE OVER AREAS WITH DIFFERENT RELEVANCES, PROVIDING PRACTICAL MECHANISMS TO IMPROVE THE OVERALL AVAILABILITY LEVEL OF MONITORING APPLICATIONS IN WIRELESS VISUAL SENSOR NETWORKS.

LARGE CITIES ARE INCREASINGLY INVESTING IN EFFICIENT MOBILITY AND SUSTAINABLE TRANSPORTATION AS AN ALTERNATIVE TO EXPENSIVE AND POLLUTANT TRADITIONAL VEHICLES. IN PARALLEL, PEOPLE ARE ALSO SEEKING CLEANER AND HEALTHIER OPTIONS FOR SHORT AND LAST-MILE DISTANCES. IN ORDER TO COPE WITH THIS TREND, WHICH HAS BOOSTED THE ADOPTION OF BIKES IN URBAN AREAS, A MAJOR CONCERN OF THE GOVERNMENTS HAS BEEN TO BUILD BIKE PATHS AND TRACKS THAT ALLOW CYCLISTS TO MOVE SAFELY AND THROUGH SHORTER DISTANCES. HOWEVER, SUCH INITIATIVES MAY RESULT IN BICYCLES INFRASTRUCTURE BUILT ALONGSIDE TRADITIONAL VEHICULAR ROADS OR ON INADEQUATE REGIONS. THEREFORE, THERE SHOULD BE A FLEXIBLE WAY TO ASSESS THE QUALITY OF BIKE PATHS AND TRACKS, COMBINING VARIABLES THAT INDICATE ADVERSE CONDITIONS FOR THE HEALTH AND SAFETY OF CYCLISTS, SUCH AS STATISTICAL RISK OF ACCIDENTS, AIR AND NOISE POLLUTION, EXCESSIVE SUNLIGHT EXPOSURE, DANGEROUS UV RADIATION, AMONG OTHERS. THIS ARTICLE THEN PROPOSES A NEW COMPREHENSIVE QUALITY METRIC THAT COMBINES SENSED ENVIRONMENTAL DATA AND HISTORICAL REPORTED INCIDENTS RELATED TO BIKE PATHS AND TRACKS, WHICH MAY BE EMPLOYED FOR TRADITIONAL PHYSICAL SIGNALING OR TO SUPPORT COMPUTER-ASSISTED SOLUTIONS FOR CYCLING MONITORING AND ALERTING. SUCH NEW METRIC EXPLOITS FUZZY LOGIC TO MODEL A GROUP OF VARIABLES TO ULTIMATELY PROVIDE A UNIFIED SAFETY AND HEALTH QUALITY LEVEL, REFERRED AS BIKEWAY. DOING SO, WE EXPECT TO ALLOW DYNAMIC AND HISTORICAL PERCEPTIONS OF HOW HEALTHY AND SAFE THE BIKE PATHS AND TRACKS ARE FOR CYCLISTS IN MODERN CITIES.

COGNITIVE RADIO NETWORKS ENABLE UNLICENSED USERS TO COMMUNICATE USING THE LICENSED SPECTRUM WITHOUT CAUSING INTERFERENCE TO LEGITIMATE USERS. TO ESTABLISH A COMMUNICATION LINK, TWO OR MORE COGNITIVE USERS MUST SIMULTANEOUSLY VISIT A COMMON AVAILABLE CHANNEL AND EXCHANGE THE HANDSHAKE INFORMATION, SUCH A PROCESS IS REFERRED TO AS RENDEZVOUS. THE SIMPLEST SOLUTION TO THE RENDEZVOUS PROBLEM IS TO USE A DEDICATED COMMON CONTROL CHANNEL. HOWEVER, IT CAN SUFFER SEVERE CONGESTION OR EVEN BE OCCUPIED BY INCUMBENT USERS, LIMITING THE FUNCTIONING OF THE COGNITIVE NETWORK. CHANNEL HOPPING (CH) TECHNIQUES OVERCOME THESE DRAWBACKS AND ALLOW COGNITIVE USERS TO RENDEZVOUS ON ANY COMMON AVAILABLE CHANNEL. IN THIS PAPER A CLASSIFICATION FRAMEWORK IS PROPOSED BASED ON RELEVANT FEATURES FOR THE DESIGN OF CH RENDEZVOUS SEQUENCES. USING THE PROPOSED FRAMEWORK, AN UNPRECEDENTED NUMBER OF CH SEQUENCES ARE REVIEWED AND CLASSIFIED. THEORETICAL PERFORMANCE METRICS OF EXISTING CH SEQUENCES ARE SUMMARIZED. FINALLY, OPEN ISSUES AND RESEARCH DIRECTIONS FOR CH SEQUENCES DESIGN ARE DISCUSSED.

WE STUDY BLOCK INTERLEAVING TECHNIQUES FOR ENHANCING ROBUSTNESS AGAINST PACKET LOSS ON WIRELESS VISION SENSOR NETWORKS. WE EVALUATE THREE TECHNIQUES: DSJ-AL INTERLEAVING, TURNER AND PETERSON (TP) TECHNIQUE, AND TORUS AUTOMORPHISMS (TA). RESULTS IN TERMS OF IMAGE QUALITY, OBTAINED TROUGH EXTENSIVE SIMULATIONS OVER MONOCHROMATIC IMAGES, SHOW THE IMPROVEMENTS PROVIDED BY INTERLEAVING TECHNIQUES IN COMPARISON WITH A SEQUENTIAL COMMUNICATION, WITH A SLIGHT FAVOR TO TA.

WIRELESS INDUSTRIAL DEVICES ARE MOSTLY ADOPTED FOR SENSOR AND ALERTING APPLICATIONS. THEY PRESENT MANY ADVANTAGES SUCH AS EASE OF INSTALLATION AND FLEXIBILITY. HOWEVER, THEIR USE IN CONTROL APPLICATIONS IS TROUBLESOME DUE TO INHERENT ISSUES OF DIGITAL WIRELESS COMMUNICATIONS SUCH AS PACKET LOSS AND DELAY. THESE PROBLEMS ARE NON TRIVIAL, AND BRING THE NECESSITY OF WORKING IN NEW RESOURCE-EFFICIENT AND ROBUST SOLUTIONS THAT BRING US CLOSER TO REAL-WORLD WIRELESS CONTROL SYSTEMS. IN THIS PAPER, A WIRELESS CONTROL CONSISTING IN LOW-POWER IEEE 802.15.4 DEVICES IS TESTED IN A COUPLED-TANK SYSTEM. THE PERFORMED TESTS ALLOW THE COMPARISON WITH THE ORIGINAL WIRED SYSTEM AND SHOW THE PERFORMANCE OF THE WIRELESS SOLUTION. DIFFERENT PARAMETERS OF THE WIRELESS DEVICES, SUCH AS SAMPLING PERIOD, NETWORK PARAMETERS AND CHANNEL NOISE, ARE TESTED. THE RESULTS ALLOW TO OBSERVE THE PROBLEMS PRESENT IN THIS TYPE OF NETWORK, GIVING SOME IDEAS OF HOW THEY CAN BE TACKLED, EVALUATING THE FEASIBILITY OF USING THIS KIND OF WIRELESS SYSTEMS UNDER DIFFERENT CONDITIONS AND CONTROL SCHEMES.

WIRELESS TECHNOLOGIES OFFER MANY ADVANTAGES IN COMMUNICATION BETWEEN INTERNET OF THINGS (IOT) DEVICES, YET, IT LACKS IN PERFORMANCE ESPECIALLY INDOORS WHERE WALLS, METAL, AND OTHER OBJECTS DETERIORATE THEIR PERFORMANCE. LORA IS A NEW TECHNOLOGY THAT MAY OFFER BETTER INDOOR PERFORMANCE. IN THIS ARTICLE, WE PRESENT AND ANALYZE LORA'S PARAMETERS, AND AIM TO OPTIMIZE THEM FOR USE IN A REINFORCED CONCRETE BUILDING. OUR EXPERIMENTAL RESULTS SHOW THAT INCREASING THE SPREADING FACTOR (SF) AND CODING RATE (CR) INCREASE THE PACKET TRANSMISSION DURATION, WHICH HAS A DETRIMENTAL EFFECT ON THE PACKET RECEPTION RATIO. MOREOVER, OUR MAIN CONTRIBUTION IS THAT WE PROPOSE AN OPTIMIZED CONFIGURATION THAT RESULTS IN A HIGHER PACKET RECEPTION RATIO IN AN INDOOR ENVIRONMENT.

WIRELESS TECHNOLOGIES ARE OPENING MANY POSSIBILITIES FOR MONITORING AND CONTROL APPLICATIONS, DRIVING MUCH RESEARCH EFFORTS IN THE LAST YEARS. REGARDING THE MAY CHALLENGING ISSUES RELATED TO INDUSTRIAL WIRELESS SENSOR NETWORKS (IWSN), EFFICIENT NODES DEPLOYMENT IS A MAJOR CONCERN SINCE IT CAN DIRECTLY IMPACT THE NETWORK BEHAVIOR. IN MANY CASES, IWSN INCLUDE PARTICULAR KIND OF NODES IN WHICH THE SENSOR UNIT AND THE WIRELESS TRANSMISSION UNITS ARE NOT LOCATED IN THE SAME PLACE. IN THIS PAPER, WE PROVIDE A SOLUTION TO THIS PROBLEM THROUGH A GENETIC ALGORITHM (GA), CAPABLE OF GIVE A SET OF POSITIONS FOR THE SET WIRELESS TRANSMITTERS, SUCH THAT EACH NODE CAN REACH A GATEWAY UNIT AND IT SATISFIES A MAXIMUM DISTANCE TO ITS RESPECTIVE SENSOR UNIT WHICH IS GIVEN BY THE MAXIMUM LENGTH OF THE CABLE CONNECTING THE ELEMENTS. RESULTS SHOW THAT OUR GA FINDS OPTIMAL SOLUTIONS FOR THE SIMPLIFIED CONSIDERED CASE IN VERY SHORT EXECUTION TIMES.

NOWADAYS, PEOPLE CAN ACCESS A WIDE RANGE OF APPLICATIONS AND SERVICES FOR MOBILE DEVICE USERS. AMONG THEM, LOCATION-BASED SERVICES (LBS), WHERE THE APPLICATION NEEDS THE USER?S POSITION TO PROVIDE THE SERVICE. SOME EXAMPLES OF THESE APPLICATIONS ARE UBER AND WAZE. NEVERTHELESS, THE REPETITIVE USE OF AN LBS CAN REVEAL CONFIDENTIAL USER INFORMATION; THUS, BEHAVIOR PATTERNS?SUCH AS DAILY ROUTES?COULD BE DEDUCED BY SOME DISHONEST LBS. FURTHERMORE, A QUERY?S KEYWORDS COULD PROVIDE INFORMATION ABOUT A USER?S HEALTH STATUS OR FUTURE POSITION WHEN IT INQUIRES ABOUT HOSPITALS OR HOTELS. THEREFORE, AN ADVERSARY CAN USE THIS INFORMATION FOR UNETHICAL PURPOSES, AND USERS NEED MECHANISMS THAT PROTECT THEIR PRIVACY. AT PRESENT, SEVERAL APPROACHES SEPARATELY TACKLE LOCATION PRIVACY, LOCATION SECURITY, AND QUERY PRIVACY. TO THE BEST OF OUR KNOWLEDGE, NO PREVIOUS WORK DEALS WITH ALL THESE MENTIONED ASPECTS SIMULTANEOUSLY ESPECIALLY WHEN USERS DEMAND CONTINUOUS PROTECTION WHEN MOVING AND ACCESSING AN LBS. THIS PAPER PROPOSES TWO BATCH TECHNIQUES TO PROVIDE LOCATION PRIVACY, LOCATION SAFETY, AND QUERY PRIVACY IN AN ENVIRONMENT THAT CONSIDERS A CONTINUOUS LBS. THESE TECHNIQUES APPLY -DIVERSITY (QUERY PRIVACY) IN A CONTEXT THAT CONTEMPLATES QUERY SEMANTICS, AS WELL AS A DIVERSE SET OF USERS? PATHS. EXTENSIVE EXPERIMENTATION SHOWS THAT BOTH TECHNIQUES ARE COST-EFFECTIVE AND SCALABLE SOLUTIONS THAT OFFER UNIFIED LOCATION PRIVACY, QUERY PRIVACY, AND LOCATION SAFETY PROTECTION FOR MANY MOBILE USERS.

IN THE CONTEXT OF MULTI-ROBOT EXPLORING, WE WORK ON THE PARTICULAR PROBLEM OF MAINTAINING COMMUNICATION LINKS BETWEEN AN EXPLORER ROBOTS AND A BASE STATION USING AUTONOMOUS ROBOT ROUTERS. IN THIS PAPER, WE PROPOSE AND DESCRIBE A KIND OF EXPLORING APPLICATION WHICH CONSIDERS A VARIABLE AMOUNT OF ROBOTS OVER TIME. THIS PROBLEM OPENS VARIOUS RESEARCH CHALLENGES. AFTERWARDS, WE FOCUS ON THE PROBLEM OF MAINTAINING A SINGLE CHAIN OF ROUTER ROBOTS BETWEEN AN EXPLORER AND THE BASE STATION. WE PROPOSE AN SIMPLE ALGORITHM FOR DRIVING ROUTER ROBOTS. THE ALGORITHM GENERATES REACTIONS USING A HEURISTIC THAT CONSIDERS NETWORK CHANGES PERCEIVED BY RSSI MEASURES. ACTIONS PERFORMED BY ROUTER ROBOTS DEPEND ON ACHIEVING GOALS CONSISTING IN ALGEBRAIC RELATIONSHIPS BETWEEN CURRENT AND PAST RSSI VALUES. SIMULATION RESULTS SHOW EFFECTIVENESS OF THE PROPOSAL ALLOWING TO DRIVE ROUTER ROBOTS TO GOOD POSITIONS, IN A FREE-OF-OBSTACLES ENVIRONMENT, CONSIDERING THE PROPOSED HEURISTIC AND THE ADOPTED SIMULATION MODEL.

THE USE OF SENSING TECHNOLOGIES IN INDUSTRIAL NVIRONMENTS HAS OPENED MANY POSSIBILITIES FOR MONITORING AND CONTROL APPLICATIONS, DRIVING MUCH RESEARCH EFFORTS IN THE LAST YEARS. AMONG THE CHALLENGING ISSUES RELATED TO INDUSTRIAL WIRELESS SENSOR NETWORKS, EFFICIENT NODES DEPLOYMENT IS A MAJOR CONCERN SINCE IT CAN DIRECTLY IMPACT THE WAY SENSORS OPERATE, WHICH HAS DEMANDED PROPER SOLUTIONS. WHEN SENSING UNITS AND TRANSCEIVER HARDWARE ARE NOT LOCATED IN THE SAME BOARD, AS IT CAN HAPPEN IN INDUSTRIAL ENVIRONMENTS, OPTIMAL DEPLOYMENT ALGORITHMS HAVE TO DEAL WITH ADDITIONAL PARAMETERS, SUCH AS THE SIZE OF THE CABLE CONNECTING THOSE ELEMENTS AND IDEAL POSITIONING FOR BOTH SENSING AND COMMUNICATION. IN SUCH WAY, THIS PAPER TACKLES THE PROBLEM OF NODE DEPLOYMENT IN INDUSTRIAL WIRELESS SENSOR NETWORKS, DISCUSSING PRACTICAL SCENARIOS AND CHALLENGING ISSUES. MOREOVER, A LOW COMPLEXITY EXAMPLE IS GIVEN IN ORDER TO ILLUSTRATE THE DIFFERENT ELEMENTS REQUIRED.