Search results for: high traffic environments.
6677 Stochastic Estimation of Wireless Traffic Parameters
Authors: Somenath Mukherjee, Raj Kumar Samanta, Gautam Sanyal
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Different services based on different switching techniques in wireless networks leads to drastic changes in the properties of network traffic. Because of these diversities in services, network traffic is expected to undergo qualitative and quantitative variations. Hence, assumption of traffic characteristics and the prediction of network events become more complex for the wireless networks. In this paper, the traffic characteristics have been studied by collecting traces from the mobile switching centre (MSC). The traces include initiation and termination time, originating node, home station id, foreign station id. Traffic parameters namely, call interarrival and holding times were estimated statistically. The results show that call inter-arrival and distribution time in this wireless network is heavy-tailed and follow gamma distributions. They are asymptotically long-range dependent. It is also found that the call holding times are best fitted with lognormal distribution. Based on these observations, an analytical model for performance estimation is also proposed.
Keywords: Wireless networks, traffic analysis, long-range dependence, heavy-tailed distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18976676 Adaptive Early Packet Discarding Policy Based on Two Traffic Classes
Authors: Rawya Rizk, Rehab Abdel-Kader, Rabab Ramadan
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Unlike the best effort service provided by the internet today, next-generation wireless networks will support real-time applications. This paper proposes an adaptive early packet discard (AEPD) policy to improve the performance of the real time TCP traffic over ATM networks and avoid the fragmentation problem. Three main aspects are incorporated in the proposed policy. First, providing quality-of-service (QoS) guaranteed for real-time applications by implementing a priority scheduling. Second, resolving the partially corrupted packets problem by differentiating the buffered cells of one packet from another. Third, adapting a threshold dynamically using Fuzzy logic based on the traffic behavior to maintain a high throughput under a variety of load conditions. The simulation is run for two priority classes of the input traffic: real time and non-real time classes. Simulation results show that the proposed AEPD policy improves throughput and fairness over that using static threshold under the same traffic conditions.Keywords: Early packet discard, Fuzzy logic, packet dropping policies, quality-of-service (QoS), TCP over ATM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14246675 Design of Service-Oriented Pervasive System for Urban Computing in Cali Zoo (OpenZoo)
Authors: Claudia L. Zuñiga, Andres F. Millan, Jose L. Abadia, Monica Lora, Andres Navarro, Juan C. Burguillo, Pedro S. Rodriguez
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The increasing popularity of wireless technologies and mobile computing devices has enabled new application areas and research. One of these new areas is pervasive systems in urban environments, because urban environments are characterized by high concentration of these technologies and devices. In this paper we will show the process of pervasive system design in urban environments, using as use case a local zoo in Cali, Colombia. Based on an ethnographic studio, we present the design of a pervasive system for urban computing based on service oriented architecture to controlled environment of Cali Zoo. In this paper, the reader will find a methodological approach for the design of similar systems, using data collection methods, conceptual frameworks for urban environments and considerations of analysis and design of service oriented systems.Keywords: Service Oriented Architecture, Urban Computing, Design of pervasive systems for urban environments, PSP Design Framework (Public Social Private), Cali Zoo.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15566674 Assessing Traffic Calming Measures for Safe and Accessible Emergency Routes in Norrkoping City in Sweden
Authors: Ghazwan Al-Haji
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Most accidents occur in urban areas, and the most related casualties are vulnerable road users (pedestrians and cyclists). The traffic calming measures (TCMs) are widely used and considered to be successful in reducing speed and traffic volume. However, TCMs create unwanted effects include: noise, emissions, energy consumption, vehicle delays and emergency response time (ERT). Different vertical and horizontal TCMs have been already applied nationally (Sweden) and internationally with different impacts. It is a big challenge among traffic engineers, planners, and policy-makers to choose and priorities the best TCMs to be implemented. This study will assess the existing guidelines for TCMs in relation to safety and ERT with focus on data from Norrkoping city in Sweden. The expected results will save lives, time, and money on particularly Swedish Roads. The study will also review newly technologies and how they can improve safety and reduce ERT.
Keywords: Traffic safety, traffic calming measures, speeding, emergency response time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8806673 Comparison of Different Types of Sources of Traffic Using SFQ Scheduling Discipline
Authors: Alejandro Gomez Suarez, H. Srikanth Kamath
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In this paper, SFQ (Start Time Fair Queuing) algorithm is analyzed when this is applied in computer networks to know what kind of behavior the traffic in the net has when different data sources are managed by the scheduler. Using the NS2 software the computer networks were simulated to be able to get the graphs showing the performance of the scheduler. Different traffic sources were introduced in the scripts, trying to establish the real scenario. Finally the results were that depending on the data source, the traffic can be affected in different levels, when Constant Bite Rate is applied, the scheduler ensures a constant level of data sent and received, but the truth is that in the real life it is impossible to ensure a level that resists the changes in work load. Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21376672 A Traffic Simulation Package Based on Travel Demand
Authors: Tuong Huan Nguyen, Quoc Bao Vo, Hai L. Vu
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In this paper we propose a new traffic simulation package, TDMSim, which supports both macroscopic and microscopic simulation on free-flowing and regulated traffic systems. Both simulators are based on travel demands, which specify the numbers of vehicles departing from origins to arrive at different destinations. The microscopic simulator implements the carfollowing model given the pre-defined routes of the vehicles but also supports the rerouting of vehicles. We also propose a macroscopic simulator which is built in integration with the microscopic simulator to allow the simulation to be scaled for larger networks without sacrificing the precision achievable through the microscopic simulator. The macroscopic simulator also enables the reuse of previous simulation results when simulating traffic on the same networks at later time. Validations have been conducted to show the correctness of both simulators.Keywords: Macroscopic, Microscopic, Simulation, Traffic, Travel demand, Fundamental diagrams.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15966671 Compact Optical Sensors for Harsh Environments
Authors: Branislav Timotijevic, Yves Petremand, Markus Luetzelschwab, Dara Bayat, Laurent Aebi
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Optical miniaturized sensors with remote readout are required devices for the monitoring in harsh electromagnetic environments. As an example, in turbo and hydro generators, excessively high vibrations of the end-windings can lead to dramatic damages, imposing very high, additional service costs. A significant change of the generator temperature can also be an indicator of the system failure. Continuous monitoring of vibrations, temperature, humidity, and gases is therefore mandatory. The high electromagnetic fields in the generators impose the use of non-conductive devices in order to prevent electromagnetic interferences and to electrically isolate the sensing element to the electronic readout. Metal-free sensors are good candidates for such systems since they are immune to very strong electromagnetic fields and given the fact that they are non-conductive. We have realized miniature optical accelerometer and temperature sensors for a remote sensing of the harsh environments using the common, inexpensive silicon Micro Electro-Mechanical System (MEMS) platform. Both devices show highly linear response. The accelerometer has a deviation within 1% from the linear fit when tested in a range 0 – 40 g. The temperature sensor can provide the measurement accuracy better than 1 °C in a range 20 – 150 °C. The design of other type of sensors for the environments with high electromagnetic interferences has also been discussed.
Keywords: Accelerometer, harsh environment, optical MEMS, pressure sensor, remote sensing, temperature sensor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11306670 Determination of Level of Service of Agrabad to CEPZ Road at Chittagong in Bangladesh
Authors: Kutub Uddin Chisty, Md. Ashraful Islam, Shahjalal Misuk
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Chittagong is the commercial capital of Bangladesh. Here Agrabad is one of the most commercial activity centers of Chittagong. Due to many light industry and commercial land use, Agrabad to CEPZ road at Agrabad is the only major road of Chittagong port city which encompasses a huge number of vehicles every day. It has many junctions which distribute traffic flow in different roads. In these junctions vehicles gather at some conflict point to create traffic jam and make the performance of the road downward. This study is parallel focused on the existing level of service with traffic volume, capacity, and speed by traffic survey. After all of these analyses the performance of the road is determined with finding the factors that influences the performance.
Keywords: Level of service, Traffic volume, Speed, Influences factors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23486669 Traffic Violation Detection System based on RFID
Authors: S. Hajeb, M. Javadi, S. M. Hashemi, P. Parvizi
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Road Traffic Accidents are a major cause of disability and death throughout the world. The control of intelligent vehicles in order to reduce human error and boost ease congestion is not accomplished solely by the aid of human resources. The present article is an attempt to introduce an intelligent control system based on RFID technology. By the help of RFID technology, vehicles are connected to computerized systems, intelligent light poles and other available hardware along the way. In this project, intelligent control system is capable of tracking all vehicles, crisis management and control, traffic guidance and recording Driving offences along the highway.
Keywords: RFID, Intelligent highway, Traffic violation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 139796668 Cost of Road Traffic Accidents in Egypt
Authors: Mohamed A. Ismail, Samar M. M. Abdelmageed
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The main objective of this paper is to estimate the cost of road traffic accidents in Egypt. The Human Capital (HC) approach, specifically the Gross-Loss-of-Output methodology, is adopted for estimation. Moreover, cost values obtained by previous national literature are updated using the inflation rates. The results indicate an estimated cost of road traffic accidents in Egypt of approximately 10 billion Egyptian Pounds (about $US 1.8 billion) for the year 2008. In addition, it is expected that this cost will rise in 2009 to 11.8 billion Egyptian Pounds (about $US 2.1 billion).
Keywords: Cost, Gross-Loss-of-Output, Human CapitalApproach, Road Traffic Accidents.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37806667 The Design of a Vehicle Traffic Flow Prediction Model for a Gauteng Freeway Based on an Ensemble of Multi-Layer Perceptron
Authors: Tebogo Emma Makaba, Barnabas Ndlovu Gatsheni
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The cities of Johannesburg and Pretoria both located in the Gauteng province are separated by a distance of 58 km. The traffic queues on the Ben Schoeman freeway which connects these two cities can stretch for almost 1.5 km. Vehicle traffic congestion impacts negatively on the business and the commuter’s quality of life. The goal of this paper is to identify variables that influence the flow of traffic and to design a vehicle traffic prediction model, which will predict the traffic flow pattern in advance. The model will unable motorist to be able to make appropriate travel decisions ahead of time. The data used was collected by Mikro’s Traffic Monitoring (MTM). Multi-Layer perceptron (MLP) was used individually to construct the model and the MLP was also combined with Bagging ensemble method to training the data. The cross—validation method was used for evaluating the models. The results obtained from the techniques were compared using predictive and prediction costs. The cost was computed using combination of the loss matrix and the confusion matrix. The predicted models designed shows that the status of the traffic flow on the freeway can be predicted using the following parameters travel time, average speed, traffic volume and day of month. The implications of this work is that commuters will be able to spend less time travelling on the route and spend time with their families. The logistics industry will save more than twice what they are currently spending.Keywords: Bagging ensemble methods, confusion matrix, multi-layer perceptron, vehicle traffic flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17776666 Adaptive Radio Resource Allocation for Multiple Traffic OFDMA Broadband Wireless Access System
Authors: Lu Yanhui, Zhang Lizhi, Yin Changchuan, Yue Guangxin
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In this paper, an adaptive radio resource allocation (RRA) algorithm applying to multiple traffic OFDMA system is proposed, which distributes sub-carrier and loading bits among users according to their different QoS requirements and traffic class. By classifying and prioritizing the users based on their traffic characteristic and ensuring resource for higher priority users, the scheme decreases tremendously the outage probability of the users requiring a real time transmission without impact on the spectrum efficiency of system, as well as the outage probability of data users is not increased compared with the RRA methods published.Keywords: OFDMA, adaptive radio resource allocation, QoS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16886665 Intelligent Transport System: Classification of Traffic Signs Using Deep Neural Networks in Real Time
Authors: Anukriti Kumar, Tanmay Singh, Dinesh Kumar Vishwakarma
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Traffic control has been one of the most common and irritating problems since the time automobiles have hit the roads. Problems like traffic congestion have led to a significant time burden around the world and one significant solution to these problems can be the proper implementation of the Intelligent Transport System (ITS). It involves the integration of various tools like smart sensors, artificial intelligence, position technologies and mobile data services to manage traffic flow, reduce congestion and enhance driver's ability to avoid accidents during adverse weather. Road and traffic signs’ recognition is an emerging field of research in ITS. Classification problem of traffic signs needs to be solved as it is a major step in our journey towards building semi-autonomous/autonomous driving systems. The purpose of this work focuses on implementing an approach to solve the problem of traffic sign classification by developing a Convolutional Neural Network (CNN) classifier using the GTSRB (German Traffic Sign Recognition Benchmark) dataset. Rather than using hand-crafted features, our model addresses the concern of exploding huge parameters and data method augmentations. Our model achieved an accuracy of around 97.6% which is comparable to various state-of-the-art architectures.
Keywords: Multiclass classification, convolution neural network, OpenCV, Data Augmentation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8146664 A Video-based Algorithm for Moving Objects Detection at Signalized Intersection
Authors: Juan Li, Chunfu Shao, Chunjiao Dong, Dan Zhao, Yinhong Liu
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Mixed-traffic (e.g., pedestrians, bicycles, and vehicles) data at an intersection is one of the essential factors for intersection design and traffic control. However, some data such as pedestrian volume cannot be directly collected by common detectors (e.g. inductive loop, sonar and microwave sensors). In this paper, a video based detection algorithm is proposed for mixed-traffic data collection at intersections using surveillance cameras. The algorithm is derived from Gaussian Mixture Model (GMM), and uses a mergence time adjustment scheme to improve the traditional algorithm. Real-world video data were selected to test the algorithm. The results show that the proposed algorithm has the faster processing speed and more accuracy than the traditional algorithm. This indicates that the improved algorithm can be applied to detect mixed-traffic at signalized intersection, even when conflicts occur.Keywords: detection, intersection, mixed traffic, moving objects.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20326663 A Technical Perspective on Roadway Safety in Eastern Province: Data Evaluation and Spatial Analysis
Authors: Muhammad Farhan, Sayed Faruque, Amr Mohammed, Sami Osman, Omar Al-Jabari, Abdul Almojil
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Saudi Arabia in recent years has seen drastic increase in traffic related crashes. With population of over 29 million, Saudi Arabia is considered as a fast growing and emerging economy. The rapid population increase and economic growth has resulted in rapid expansion of transportation infrastructure, which has led to increase in road crashes. Saudi Ministry of Interior reported more than 7,000 people killed and 68,000 injured in 2011 ranking Saudi Arabia to be one of the worst worldwide in traffic safety. The traffic safety issues in the country also result in distress to road users and cause and economic loss exceeding 3.7 billion Euros annually. Keeping this in view, the researchers in Saudi Arabia are investigating ways to improve traffic safety conditions in the country. This paper presents a multilevel approach to collect traffic safety related data required to do traffic safety studies in the region. Two highway corridors including King Fahd Highway 39 kilometre and Gulf Cooperation Council Highway 42 kilometre long connecting the cities of Dammam and Khobar were selected as a study area. Traffic data collected included traffic counts, crash data, travel time data, and speed data. The collected data was analysed using geographic information system to evaluate any correlation. Further research is needed to investigate the effectiveness of traffic safety related data when collected in a concerted effort.
Keywords: Crash Data, Data Collection, Traffic Safety.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23516662 An Interference Reduction Strategy for TDD-OFDMA Cellular Systems
Authors: Koudjo M. Koumadi, Kester Quist-Aphetsi, Robert A. Sowah, Amevi Acakpovi
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Downlink/Uplink (DL/UL) time slot allocation (TSA) in time division duplex (TDD) systems is generally uniform for all the cells. This TSA however is not efficient in case of different traffic asymmetry ratios in different cells. We first propose a new 3-coordinate architecture to identify cells in an orthogonal frequency division multiple access (OFDMA) system where each cell is divided into three sectors. Then, this coordinate system is used to derive a TSA for symmetric traffic. Mathematical analysis and simulations are used to show that the proposed TSA outperforms the traditional all uniform type of TSA in terms of total intercellular interference, even under uniform symmetrical traffic. Two adaptation strategies are further proposed to adjust the proposed TSA to asymmetrical traffic with different DL/UL traffic ratios in different cells. Further simulation results show that the adaptation strategies also yield higher signal-to-interference ratio (SIR).
Keywords: Crossed TSA, different-entity interference, same-entity interference, uniform TSA
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22316661 Possibilistic Clustering Technique-Based Traffic Light Control for Handling Emergency Vehicle
Authors: F. Titouna, S. Benferhat, K. Aksa, C. Titouna
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A traffic light gives security from traffic congestion,reducing the traffic jam, and organizing the traffic flow. Furthermore,increasing congestion level in public road networks is a growingproblem in many countries. Using Intelligent Transportation Systemsto provide emergency vehicles a green light at intersections canreduce driver confusion, reduce conflicts, and improve emergencyresponse times. Nowadays, the technology of wireless sensornetworks can solve many problems and can offer a good managementof the crossroad. In this paper, we develop a new approach based onthe technique of clustering and the graphical possibilistic fusionmodeling. So, the proposed model is elaborated in three phases. Thefirst one consists to decompose the environment into clusters,following by the fusion intra and inter clusters processes. Finally, wewill show some experimental results by simulation that proves theefficiency of our proposed approach.KeywordsTraffic light, Wireless sensor network, Controller,Possibilistic network/Bayesain network.
Keywords: Traffic light, Wireless sensor network, Controller, Possibilistic network/Bayesain network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18126660 Use of Hair as an Indicator of Environmental Lead Pollution: Characteristics and Seasonal Variation of Lead Pollution in Egypt
Authors: A. A. K. Abou-Arab, M. A. Abou Donia, Nevin E. Sharaf, Sherif R. Mohamed, A. K. Enab
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Lead being a toxic heavy metal that mankind is exposed to the highest levels of this metal from environmental pollutants. A total of 180 Male scalp hair samples were collected from different environments in Greater Cairo (GC), i.e. industrial, heavy traffic and rural areas (60 samples from each) having different activities during the period of, 1/5/2010 to 1/11/2012. Hair samples were collected during five stages. Data proved that the concentration of lead in male industrial areas of Cairo ranged between 6.2847 to 19.0432 μg/g, with mean value of 12.3288 μg/g. On the other hand, lead content of hair samples of residential-traffic areas ranged between 2.8634 to 16.3311 μg/g with mean value of 9.7552 μg/g. While lead concentration on the hair of the male residents living in rural area ranged between 1.0499-9.0402μg/g with mean value of 4.7327 μg/g. The Pb concentration in scalp hair of Cairo residents of residential-traffic and rural traffic areas was observed to follow the same pattern. The pattern was that of decrease concentration of summer and its increase in winter. Then, there was a marked increase in Pb concentration of summer 2012, and this increase was significant. These were obviously seen for the residential-traffic and rural areas residents. Pb pollution in residents of industrial areas showed the same seasonal pattern, but there was marked to decrease in Pb concentration of summer 2012, and this decrease was significant. Lead pollution in residents of GC was serious. It is worth noting that the atmosphere is still contaminated by lead despite a decade of using unleaded gasoline. Strong seasonal variation in higher Pb concentration on winter than in summer was found. Major contributions to the pollution with Pb could include industry emissions, motor vehicle emissions and long transported dust from outside Cairo. More attention should be paid to the reduction of Pb content of the urban aerosol and to the Pb pollution health.
Keywords: Hair, lead, environmental exposure, seasonal variations, Egypt.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16916659 Dynamic Network Routing Method Based on Chromosome Learning
Authors: Xun Liang
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In this paper, we probe into the traffic assignment problem by the chromosome-learning-based path finding method in simulation, which is to model the driver' behavior in the with-in-a-day process. By simply making a combination and a change of the traffic route chromosomes, the driver at the intersection chooses his next route. The various crossover and mutation rules are proposed with extensive examples.
Keywords: Chromosome learning, crossover, mutation, traffic path finding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13476658 Anomaly Detection and Characterization to Classify Traffic Anomalies Case Study: TOT Public Company Limited Network
Authors: O. Siriporn, S. Benjawan
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This paper represents four unsupervised clustering algorithms namely sIB, RandomFlatClustering, FarthestFirst, and FilteredClusterer that previously works have not been used for network traffic classification. The methodology, the result, the products of the cluster and evaluation of these algorithms with efficiency of each algorithm from accuracy are shown. Otherwise, the efficiency of these algorithms considering form the time that it use to generate the cluster quickly and correctly. Our work study and test the best algorithm by using classify traffic anomaly in network traffic with different attribute that have not been used before. We analyses the algorithm that have the best efficiency or the best learning and compare it to the previously used (K-Means). Our research will be use to develop anomaly detection system to more efficiency and more require in the future.
Keywords: Unsupervised, clustering, anomaly, machine learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21116657 Mitigation of ISI for Next Generation Wireless Channels in Outdoor Vehicular Environments
Authors: Mohd. Israil, M. Salim Beg
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In order to accommodate various multimedia services, next generation wireless networks are characterized by very high transmission bit rates. Thus, in such systems and networks, the received signal is not only limited by noise but - especially with increasing symbols rate often more significantly by the intersymbol interference (ISI) caused by the time dispersive radio channels such as those are used in this work. This paper deals with the study of the performance of detector for high bit rate transmission on some worst case models of frequency selective fading channels for outdoor mobile radio environments. This paper deals with a number of different wireless channels with different power profiles and different number of resolvable paths. All the radio channels generated in this paper are for outdoor vehicular environments with Doppler spread of 100 Hz. A carrier frequency of 1800 MHz is used and all the channels used in this work are such that they are useful for next generation wireless systems. Schemes for mitigation of ISI with adaptive equalizers of different types have been investigated and their performances have been investigated in terms of BER measured as a function of SNR.Keywords: Mobile channels, Rayleigh Fading, Equalization, NMLD.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14206656 The Rail Traffic Management with Usage of C-OTDR Monitoring Systems
Authors: Andrey V. Timofeev, Dmitry V. Egorov, Viktor M. Denisov
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This paper presents development results of usage of C-OTDR monitoring systems for rail traffic management. The COTDR method is based on vibrosensitive properties of optical fibers. Analysis of Rayleigh backscattering radiation parameters changes which take place due to microscopic seismoacoustic impacts on the optical fiber allows to determine seismoacoustic emission source positions and to identify their types. This approach proved successful for rail traffic management (moving block system, weigh- in-motion system etc.).Keywords: C-OTDR systems, moving block-sections, rail traffic management, Rayleigh backscattering, weigh-in-motion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23186655 Traffic Density Measurement by Automatic Detection of Vehicles Using Gradient Vectors from Aerial Images
Authors: Saman Ghaffarian, Ilgın Gökasar
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This paper presents a new automatic vehicle detection method from very high resolution aerial images to measure traffic density. The proposed method starts by extracting road regions from image using road vector data. Then, the road image is divided into equal sections considering resolution of the images. Gradient vectors of the road image are computed from edge map of the corresponding image. Gradient vectors on the each boundary of the sections are divided where the gradient vectors significantly change their directions. Finally, number of vehicles in each section is carried out by calculating the standard deviation of the gradient vectors in each group and accepting the group as vehicle that has standard deviation above predefined threshold value. The proposed method was tested in four very high resolution aerial images acquired from Istanbul, Turkey which illustrate roads and vehicles with diverse characteristics. The results show the reliability of the proposed method in detecting vehicles by producing 86% overall F1 accuracy value.Keywords: Aerial images, intelligent transportation systems, traffic density measurement, vehicle detection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29356654 Optical Flow Based System for Cross Traffic Alert
Authors: Giuseppe Spampinato, Salvatore Curti, Ivana Guarneri, Arcangelo Bruna
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This document describes an advanced system and methodology for Cross Traffic Alert (CTA), able to detect vehicles that move into the vehicle driving path from the left or right side. The camera is supposed to be not only on a vehicle still, e.g. at a traffic light or at an intersection, but also moving slowly, e.g. in a car park. In all of the aforementioned conditions, a driver’s short loss of concentration or distraction can easily lead to a serious accident. A valid support to avoid these kinds of car crashes is represented by the proposed system. It is an extension of our previous work, related to a clustering system, which only works on fixed cameras. Just a vanish point calculation and simple optical flow filtering, to eliminate motion vectors due to the car relative movement, is performed to let the system achieve high performances with different scenarios, cameras and resolutions. The proposed system just uses as input the optical flow, which is hardware implemented in the proposed platform and since the elaboration of the whole system is really speed and power consumption, it is inserted directly in the camera framework, allowing to execute all the processing in real-time.
Keywords: Clustering, cross traffic alert, optical flow, real time, vanishing point.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8106653 Digital Learning Environments for Joint Master in Science Programmes in Building and Construction in Europe: Experimenting with Tools and Technologies
Authors: E. Dado, R. Beheshti
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Recent developments in information and communication technologies (ICT) have created excellent conditions for profoundly enhancing the traditional learning and teaching practices. New modes of teaching in higher education subjects can profoundly enhance ones ability to proactively constructing his or her personal learning universe. These developments have contributed to digital learning environments becoming widely available and accessible. In addition, there is a trend towards enlargement and specialization in higher education in Europe. With as a result that existing Master of Science (MSc) programmes are merged or new programmes have been established that are offered as joint MSc programmes to students. In these joint MSc programmes, the need for (common) digital learning environments capable of surmounting the barriers of time and location has become evident. This paper discusses the past and ongoing efforts to establish such common digital learning environments in two joint MSc programmes in Europe and discusses the way technology-based learning environments affect the traditional way of learning.Keywords: education, engineering, learning environments, ICT.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15496652 Estimating the Traffic Impacts of Green Light Optimal Speed Advisory Systems Using Microsimulation
Authors: C. B. Masera, M. Imprialou, L. Budd, C. Morton
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Even though signalised intersections are necessary for urban road traffic management, they can act as bottlenecks and disrupt traffic operations. Interrupted traffic flow causes congestion, delays, stop-and-go conditions (i.e. excessive acceleration/deceleration) and longer journey times. Vehicle and infrastructure connectivity offers the potential to provide improved new services with additional functions of assisting drivers. This paper focuses on one of the applications of vehicle-to-infrastructure communication namely Green Light Optimal Speed Advisory (GLOSA). To assess the effectiveness of GLOSA in the urban road network, an integrated microscopic traffic simulation framework is built into VISSIM software. Vehicle movements and vehicle-infrastructure communications are simulated through the interface of External Driver Model. A control algorithm is developed for recommending an optimal speed that is continuously updated in every time step for all vehicles approaching a signal-controlled point. This algorithm allows vehicles to pass a traffic signal without stopping or to minimise stopping times at a red phase. This study is performed with all connected vehicles at 100% penetration rate. Conventional vehicles are also simulated in the same network as a reference. A straight road segment composed of two opposite directions with two traffic lights per lane is studied. The simulation is implemented under 150 vehicles per hour and 200 per hour traffic volume conditions to identify how different traffic densities influence the benefits of GLOSA. The results indicate that traffic flow is improved by the application of GLOSA. According to this study, vehicles passed through the traffic lights more smoothly, and waiting times were reduced by up to 28 seconds. Average delays decreased for the entire network by 86.46% and 83.84% under traffic densities of 150 vehicles per hour per lane and 200 vehicles per hour per lane, respectively.
Keywords: Connected vehicles, GLOSA, intelligent transportation systems, infrastructure-to-vehicle communication.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16136651 Frequency Offset Estimation Schemes Based On ML for OFDM Systems in Non-Gaussian Noise Environments
Authors: Keunhong Chae, Seokho Yoon
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In this paper, frequency offset (FO) estimation schemes robust to the non-Gaussian noise environments are proposed for orthogonal frequency division multiplexing (OFDM) systems. First, a maximum-likelihood (ML) estimation scheme in non-Gaussian noise environments is proposed, and then, the complexity of the ML estimation scheme is reduced by employing a reduced set of candidate values. In numerical results, it is demonstrated that the proposed schemes provide a significant performance improvement over the conventional estimation scheme in non-Gaussian noise environments while maintaining the performance similar to the estimation performance in Gaussian noise environments.
Keywords: Frequency offset estimation, maximum-likelihood, non-Gaussian noise environment, OFDM, training symbol.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19486650 Direct Growth Rates of the Information Model for Traffic at the Service of Sustainable Development of Tourism in Dubrovacko-Neretvanska County 2014-2020
Authors: V. Viduĉić, J. Žanić Mikuliĉić, M. Raĉić, K. Sladojević
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The research presented in this paper has been focused on analysing the impact of traffic on the sustainable development of tourism in Croatia's Dubrovacko-Neretvanska County by the year 2020, based on the figures and trends reported in 2014 and using the relevant variables that characterise the synergy of traffic and tourism in, speaking from the geographic viewpoint, the most problematic county in the Republic of Croatia. The basic hypothesis has been confirmed through scientifically obtained research results, through the quantification of the model's variables and the direct growth rates of the designed model. On the basis of scientific insights into the sustainable development of traffic and tourism in Dubrovacko- Neretvanska County, it is possible to propose a new information model for traffic at the service of the sustainable development of tourism in the County for the period 2014-2020.
Keywords: Environment protection, hotel industry, private sector, quantification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19876649 A Robust Adaptive Congestion Control Strategy for Large Scale Networks with Differentiated Services Traffic
Authors: R. R. Chen, K. Khorasani
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In this paper, a robust decentralized congestion control strategy is developed for a large scale network with Differentiated Services (Diff-Serv) traffic. The network is modeled by a nonlinear fluid flow model corresponding to two classes of traffic, namely the premium traffic and the ordinary traffic. The proposed congestion controller does take into account the associated physical network resource limitations and is shown to be robust to the unknown and time-varying delays. Our proposed decentralized congestion control strategy is developed on the basis of Diff-Serv architecture by utilizing a robust adaptive technique. A Linear Matrix Inequality (LMI) condition is obtained to guarantee the ultimate boundedness of the closed-loop system. Numerical simulation implementations are presented by utilizing the QualNet and Matlab software tools to illustrate the effectiveness and capabilities of our proposed decentralized congestion control strategy.
Keywords: Congestion control, Large scale networks, Decentralized control, Differentiated services traffic, Time-delay systems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19896648 Feasibility Study of Distributed Lightless Intersection Control with Level 1 Autonomous Vehicles
Authors: Bo Yang, Christopher Monterola
Abstract:
Urban intersection control without the use of the traffic light has the potential to vastly improve the efficiency of the urban traffic flow. For most proposals in the literature, such lightless intersection control depends on the mass market commercialization of highly intelligent autonomous vehicles (AV), which limits the prospects of near future implementation. We present an efficient lightless intersection traffic control scheme that only requires Level 1 AV as defined by NHTSA. The technological barriers of such lightless intersection control are thus very low. Our algorithm can also accommodate a mixture of AVs and conventional vehicles. We also carry out large scale numerical analysis to illustrate the feasibility, safety and robustness, comfort level, and control efficiency of our intersection control scheme.
Keywords: Intersection control, autonomous vehicles, traffic modelling, intelligent transport system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1623