Effects of concept map approach on students' attitude and motivation towards documenting computing capstone projects
- ملخص البحث
Given their importance in assessing the objectives of computing programs, capstone projects have been included in the present curriculum. Through these projects, the issues in software development practice are directly experienced by the students. This paper provided students with a full picture of these issues by using concept maps. To present a comprehensive rubricbased documentation of this project, this paper employs a conceptual map instructional approach and finds a significant overlap between the management issues associated with the project management life cycle and the technical issues associated with the software development life cycle. Although these issues must be treated separately, they must be related with each other in software project reporting. A questionnaire survey is employed to measure the students' attitude and motivation (i.e., drivers of teaching) towards using proposed concept map to support project documentation. The survey findings indicate that the learning motivation and attitude of students can be improved by employing the proposed teaching approach.
- رابط البحث
- الكلمات المفتاحية
capstone project; concept maps; technical reporting.
Multi-generations Key Pre-distribution's Technique in Wireless Sensor Networks
- ملخص البحث
Network future relies nowadays on producing a low-cost and effective network in less cost. One of the most effective network solutions is the Wireless Sensor Networks (WSN). Security is the main challenge of this kind of networks where the nodes in such network are restricted by the power consumption due to limited power source. The main factor of WSN security is the key management part which consists of creating, distributing, and using the keys in the network lifecycle. Key Pre-distribution technique is approved to work efficiently to support WSN security. One of the drawbacks of this technique is that it is not supporting renewing and refreshing keys to support multi-generations sensors. In this work we present a novel technique to reproduce new keys from old pre-distributed keys in efficient way to save the power.
- رابط البحث
- الكلمات المفتاحية
Sooawsn: a secure object oriented architecture for wireless sensor networks
- ملخص البحث
Abstract
Authors
References
Cited By
Index Terms
Publication
Reviews
Comments
Secure Communication is a mandatory requirement in many network applications. Wireless sensor networks (WSN) require more attention regarding securing the communication between its nodes. In these kinds of networks, communications may occur between sensors themselves or between sensors and the node that is responsible of collecting information from sensors which is called a Base Station (BS). Communications between sensors are not completely controlled by the BS, where sensors are able to communicate directly with each others. Limited resources of such kind of networks require special techniques to be applied on those kinds of networks that differ from those applied to other kinds of networks. Some researches focus on providing the Sensor-Sensor communication and others focused on Sensor-BS communication.
From the security side, many proposals present security solutions to be applied on those communications. Few proposals provide complete key management solutions to cover both kind of communications (i.e. Sensor-Sensor, and Sensor-BS communications). However, these proposals do not discuss the detection of the compromised nodes under network attacks. Some other proposals discuss the issue of compromised nodes detections.
In this dissertation, we present a complete framework that covers all the aspects of WSN communications (i.e. Routing Protocol, Security Key Management, and Intrusion Detection). The framework is called Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN). We present each module as an object that contains some methods that cover all the aspects of that part. Then, these objects are applied together as a complete solution or as methods selected from each object to create a partial solution that satisfies specific application's requirements. The first model relates to routing technique. It contains one method for routing the information from sensors to the BS. It relies on Dynamic Clustering hierarchy where sensors are grouped into clusters with clusters heads. These clusters heads forward the data to the BS from other sensors. The second model relates to key management protocol. This model consists of three methods. First method relies on the Key-Predistribution technique where the BS assigns groups of keys with their IDs to the sensors prior to network deployment in order to be used during network communications. The second method adopts the Public-Private technique to digitally sign the message and for keys exchanges. The third method is an improvement and an addition to the Key-predistribution technique to support multi-generation network. In this method the keys are generated and renewed locally in each sensor without the need of the BS. The third model relates to intrusion detection and recovery. It consists of two methods; the Public-Private method and Routing-Attack method. The first method involves the authentication of the sensor using the digital signature. The second method monitors the behavior of the sensors by analyzing their activities compared to previous activities.
- رابط البحث
- الكلمات المفتاحية
Clustered Hierarchy in Sensor Networks: Performance and Security
- ملخص البحث
Many papers have been proposed in order to increase the wireless sensor networks performance; This kind of network has limited resources, where the energy in each sensor came from a small battery that sometime is hard to be replaced or recharged. Transmission energy is the most concern part where the higher energy consumption takes place. Clustered hierarchy has been proposed in many papers; in most cases, it provides the network with better performance than other protocols. In our paper, first we discuss some of techniques, relates to this protocol, that have been proposed for energy efficiency; some of them were proposed to provide the network with more security level. Our proposal then suggests some modifications to some of these techniques to provide the network with more energy saving that should lead to high performance; also we apply our technique on an existing one that proposed to increase the security level of cluster sensor networks.
- رابط البحث
- الكلمات المفتاحية
Modified LEACH–Energy Efficient Wireless Networks Communication
- ملخص البحث
Many algorithms and techniques were proposed to increase the efficiency of Sensor Networks. Due to high restrictions of this kind of networks, where the resources are limited, many factors may affect its work. Theses factors are: System throughput, system delay, and energy. Clustering protocols have been propose to decrease system throughput and system delay, and increase energy saving. In this paper, we propose a new technique that can be applied to sensor networks to produce high performance and stable Sensor Networks.
- رابط البحث
- الكلمات المفتاحية
LEACH (Low Energy Adaptive Clustering Hierarchy) Sensor Networks Network Performance Routing
Security in Wireless Sensor Networks: Key Management Module in SOOAWSN
- ملخص البحث
Due to high restrictions in wireless sensor networks, where the resources are limited, clustering protocols for routing organization have been proposed in much research for increasing system throughput, decreasing system delay and saving energy. Even these algorithms have proposed some levels of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper we focus on how to achieve the highest possible level of security by applying new key management technique that can be used during wireless sensor networks communications. For our proposal to be more effective and applicable to a large number of wireless sensor networks applications, we work on a special kind of architecture that have been proposed to cluster hierarchy of wireless sensor networks and we pick one of the most interesting protocols that have been proposed for this kind of architecture, which is LEACH. This proposal is a module of a complete solution that we are developing to cover all the aspects of wireless sensor networks communication which is labeled Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN).
- رابط البحث
- الكلمات المفتاحية
Armor-LEACH - Energy Efficient, Secure Wireless Networks Communication
- ملخص البحث
Abstract:
The use of sensor networks is increasing day by day; which offer more research topics to be discuss and modified; one of these topics is the power consumption that has to be reduced as possible, where the resources are limited; another topic is the security level that should be offer by such kind of networks. Clustered networks have been proposed in many papers to reduce the power consumption in sensor networks. LEACH is one of the most interested techniques that offer an efficient way to minimize the power consumption in sensor networks. TCCA provides LEACH with higher performance, by applying some modification to the way LEACH works. In this paper we propose a hybrid technique that offers a complete solution for routing in sensor networks. This technique reduces power consumption, increases security level, and decrease data overload for sensor networks communication.
- رابط البحث
- الكلمات المفتاحية
Routing in Sensor Networks: Performance and Security in clustered networks
- ملخص البحث
Due to high restrictions in sensor network, where the resources are limited, clustering protocols for routing organization have been proposed in much research for increasing system throughput, decreasing system delay and saving energy. Even these algorithms have proposed some levels of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper we focus on how to apply the highest possible level of security to sensor networks and at the same time increase the performance of these networks by changing the way that sensors communicate with each other.
- رابط البحث
- الكلمات المفتاحية
An Adaptive Approach for Real Time Advertising System based on User Location and Interests
- ملخص البحث
Due to the wide spread of the smart phones around the world, a special demand occurs in the mobile marketing. Real time advertising is still challenging due to its hard requirements: Tracking of customer location, knowledge of customer interests, knowledge of advertisers data and the ability to efficiently provide the customer with available advertiser’s data securely. Materials and Methods: This study introduces a comprehensive work for designing, developing and evaluation of a mobile platform for real time advertising system. This system is built by adopting well-known algorithms for each requirement concerning real time advertising system. To investigate the performance of the developed system, several experiments are conducted using a simulation program built specially for this system to measure two main factors: The missing advertisements and the delay time. Results: The simulation results show that the performance of the proposed system is very promising and revealing the importance and possibility of developing adaptive real time advertising system based on customer’s location and interest. The proposed system considered as a promising and a stable media for advertisement according to the missing advertisements and the time required for the advertisement to be received by the customer. Conclusion: This study introduce a novel system, which is built to satisfy user interests for advertisements based on his location. The system built using three subsystems to ensure its ability to produce data in real time and to handle huge traffic of subscribers and advertiser. It has also the ability to integrate different systems into it to satisfy any future requirements.
- رابط البحث
- الكلمات المفتاحية
Armor-LEACH for Wireless Sensor Network
- ملخص البحث
The use of sensor networks is increasing day by day; which offer more research topics to be discuss and modified; one of these topics is the power consumption that has to be reduced as possible, where the resources are limited; another topic is the security level that should be offer by such kind of networks. Clustered networks have been proposed in many papers to reduce the power consumption in sensor networks. LEACH is one of the most interested techniques that offer an efficient way to minimize the power consumption in sensor networks. TCCA provides LEACH with higher performance, by applying some modification to the way LEACH works. In this paper we combine two of the most powerful proposed techniques that can be applied on LEACH to reduce the power consumption and to increase the level of security.
- رابط البحث
- الكلمات المفتاحية
ARABIC HANDWRITTEN WORD CATEGORY CLASSIFICATION USING BAG OF FEATURES.
- ملخص البحث
Human writing is highly variable and inconsistent, and this makes the offline recognition of handwritten words extremely challenging. This paper describes a novel approach that can be employed for the offline recognition of handwritten Arabic words. Through conceptualizing each word as single, inseparable objects, the proposed approach aims to recognize words in accordance with their complete shape. This paper describes the bag-of-visual-words method that has been effectively employed for the purposes of classifying images. The study consisted of four main stages. First, a set of image patches were sampled for the purposes of training, and a speeded up robust features (SURF) descriptor was then used to characterize them. Following that, the bag-of-visual-words model was employed through constructing the K-means clustering algorithm. A histogram of each whole world was developed and this operated as the image feature vector. This was employed to train the support vector machine classifier, which was then able to effectively distinguish between handwritten words. Finally, the effectiveness of the proposed method was tested using a sample of Arabic words extracted from the IFN/ENIT database and the results indicated that the bag-of-visual-words approach represents a promising method of recognizing and classifying handwritten Arabic words. The best and average recognition rates of the proposed method are 85% and 75% respectively.
- رابط البحث
- الكلمات المفتاحية
An Efficient Bit-Level Lossless Grayscale Image Compression Based on Adaptive Source Mapping.
- ملخص البحث
Image compression is an essential technique for saving time and storage space for the gigantic amount of data generated by images. This paper introduces an adaptive source-mapping scheme that greatly improves bitlevel lossless grayscale image compression. In the proposed mapping scheme, the frequency of occurrence of each symbol in the original image is computed. According to their corresponding frequencies, these symbols are sorted in descending order. Based on this order, each symbol is replaced by an 8-bit weighted fixed-length code. This replacement will generate an equivalent binary source with an increased length of successive identical symbols (0s or 1s). Different experiments using Lempel-Ziv lossless image compression algorithms have been conducted on the generated binary source. Results show that the newly proposed mapping scheme achieves some dramatic improvements in regards to compression ratios.
- رابط البحث
- الكلمات المفتاحية
Bit-Level, Lempel-Ziv Coding, Lossless Image Compression, Source Encoding
Connected tours for sensor networks using clustering techniques
- ملخص البحث
We consider a new problem related to data gathering in sensor networks based on multiple mobile sink elements. The problem involves the planning of a set of tours (cycles or closed paths) that cover all sensors and are connected: Each tour must be connected to at least one other tour by including a common network location. These connection points are used as data relays. The mobile element gathering data from its assigned path can leave all collected data on the designated relay point, so that it is picked up by the mobile element on the overlapping tour. This way, all data can eventually be transported to the network gateway, or any other node in the network. We formally define this new connected tour cover problem, which is a generalization of the travelling salesman problem (TSP) and therefore inherits all the known hardness properties of TSP. Then we propose a heuristic that solves this problem based on clustering, and establish its practical performance using an extensive experimental evaluation.
- رابط البحث
- الكلمات المفتاحية
Mobile communication, Clustering algorithms, Mobile computing, Planning, Wireless sensor networks, Approximation methods, Approximation algorithms
Length-Constrained and Connected Tours for Sensor Networks
- ملخص البحث
We consider a variant of the data gathering problem in sensor networks using multiple mobile elements, where each sensor must be visited with a given minimum frequency. We will construct solutions to this problem where the network is partitioned to possibly several regions, so that a single mobile element visits every node within each region. Therefore we need to partition the network and construct mobile element paths (or tours in our case) that are not too long, so that every sensor can be visited with the required frequency. Assuming the mobile elements move with some average speed, a periodic constraint for visiting a node, translates to a tour length constraint for the mobile element that visits this node. We construct solutions to this problem based on connected tour covers. We propose a divide-and-conquer heuristic to design connected tour covers for this problem and evaluate the performance using several experiments.
- رابط البحث
- الكلمات المفتاحية
Mobile communication, Approximation algorithms, Mobile computing, Approximation methods, Wireless sensor networks, Robot sensing systems, Educational institutions
Security in wireless sensor networks: key intrusion detection module in SOOAWSN
- ملخص البحث
Due to restrictions and limited resources in wireless sensor networks, clustering for routing organization have been proposed literature to increase system throughput, decrease system delay and save energy. Although these algorithms proposed some degree of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper, we propose two methods of intrusion detection techniques that can be used during wireless sensor networks communications. The proposed solution perfectly fits all kinds of wireless sensor networks that follow the clustering hierarchy distribution. In addition, it may fit many other distribution techniques. The proposed solution is integrated in a complete solution for wireless sensor network that covers all the network lifecycle from the time it deployed which is called Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN).
- رابط البحث
- الكلمات المفتاحية
Effects of concept map approach on students' attitude and motivation towards documenting computing capstone projects
- ملخص البحث
Given their importance in assessing the objectives of computing programs, capstone projects have been included in the present curriculum. Through these projects, the issues in software development practice are directly experienced by the students. This paper provided students with a full picture of these issues by using concept maps. To present a comprehensive rubricbased documentation of this project, this paper employs a conceptual map instructional approach and finds a significant overlap between the management issues associated with the project management life cycle and the technical issues associated with the software development life cycle. Although these issues must be treated separately, they must be related with each other in software project reporting. A questionnaire survey is employed to measure the students' attitude and motivation (i.e., drivers of teaching) towards using proposed concept map to support project documentation. The survey findings indicate that the learning motivation and attitude of students can be improved by employing the proposed teaching approach.
- رابط البحث
- الكلمات المفتاحية
capstone project; concept maps; technical reporting.
Multi-generations Key Pre-distribution's Technique in Wireless Sensor Networks
- ملخص البحث
Network future relies nowadays on producing a low-cost and effective network in less cost. One of the most effective network solutions is the Wireless Sensor Networks (WSN). Security is the main challenge of this kind of networks where the nodes in such network are restricted by the power consumption due to limited power source. The main factor of WSN security is the key management part which consists of creating, distributing, and using the keys in the network lifecycle. Key Pre-distribution technique is approved to work efficiently to support WSN security. One of the drawbacks of this technique is that it is not supporting renewing and refreshing keys to support multi-generations sensors. In this work we present a novel technique to reproduce new keys from old pre-distributed keys in efficient way to save the power.
- رابط البحث
- الكلمات المفتاحية
Sooawsn: a secure object oriented architecture for wireless sensor networks
- ملخص البحث
Abstract
Authors
References
Cited By
Index Terms
Publication
Reviews
Comments
Secure Communication is a mandatory requirement in many network applications. Wireless sensor networks (WSN) require more attention regarding securing the communication between its nodes. In these kinds of networks, communications may occur between sensors themselves or between sensors and the node that is responsible of collecting information from sensors which is called a Base Station (BS). Communications between sensors are not completely controlled by the BS, where sensors are able to communicate directly with each others. Limited resources of such kind of networks require special techniques to be applied on those kinds of networks that differ from those applied to other kinds of networks. Some researches focus on providing the Sensor-Sensor communication and others focused on Sensor-BS communication.
From the security side, many proposals present security solutions to be applied on those communications. Few proposals provide complete key management solutions to cover both kind of communications (i.e. Sensor-Sensor, and Sensor-BS communications). However, these proposals do not discuss the detection of the compromised nodes under network attacks. Some other proposals discuss the issue of compromised nodes detections.
In this dissertation, we present a complete framework that covers all the aspects of WSN communications (i.e. Routing Protocol, Security Key Management, and Intrusion Detection). The framework is called Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN). We present each module as an object that contains some methods that cover all the aspects of that part. Then, these objects are applied together as a complete solution or as methods selected from each object to create a partial solution that satisfies specific application's requirements. The first model relates to routing technique. It contains one method for routing the information from sensors to the BS. It relies on Dynamic Clustering hierarchy where sensors are grouped into clusters with clusters heads. These clusters heads forward the data to the BS from other sensors. The second model relates to key management protocol. This model consists of three methods. First method relies on the Key-Predistribution technique where the BS assigns groups of keys with their IDs to the sensors prior to network deployment in order to be used during network communications. The second method adopts the Public-Private technique to digitally sign the message and for keys exchanges. The third method is an improvement and an addition to the Key-predistribution technique to support multi-generation network. In this method the keys are generated and renewed locally in each sensor without the need of the BS. The third model relates to intrusion detection and recovery. It consists of two methods; the Public-Private method and Routing-Attack method. The first method involves the authentication of the sensor using the digital signature. The second method monitors the behavior of the sensors by analyzing their activities compared to previous activities.
- رابط البحث
- الكلمات المفتاحية
Clustered Hierarchy in Sensor Networks: Performance and Security
- ملخص البحث
Many papers have been proposed in order to increase the wireless sensor networks performance; This kind of network has limited resources, where the energy in each sensor came from a small battery that sometime is hard to be replaced or recharged. Transmission energy is the most concern part where the higher energy consumption takes place. Clustered hierarchy has been proposed in many papers; in most cases, it provides the network with better performance than other protocols. In our paper, first we discuss some of techniques, relates to this protocol, that have been proposed for energy efficiency; some of them were proposed to provide the network with more security level. Our proposal then suggests some modifications to some of these techniques to provide the network with more energy saving that should lead to high performance; also we apply our technique on an existing one that proposed to increase the security level of cluster sensor networks.
- رابط البحث
- الكلمات المفتاحية
Modified LEACH–Energy Efficient Wireless Networks Communication
- ملخص البحث
Many algorithms and techniques were proposed to increase the efficiency of Sensor Networks. Due to high restrictions of this kind of networks, where the resources are limited, many factors may affect its work. Theses factors are: System throughput, system delay, and energy. Clustering protocols have been propose to decrease system throughput and system delay, and increase energy saving. In this paper, we propose a new technique that can be applied to sensor networks to produce high performance and stable Sensor Networks.
- رابط البحث
- الكلمات المفتاحية
LEACH (Low Energy Adaptive Clustering Hierarchy) Sensor Networks Network Performance Routing
Security in Wireless Sensor Networks: Key Management Module in SOOAWSN
- ملخص البحث
Due to high restrictions in wireless sensor networks, where the resources are limited, clustering protocols for routing organization have been proposed in much research for increasing system throughput, decreasing system delay and saving energy. Even these algorithms have proposed some levels of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper we focus on how to achieve the highest possible level of security by applying new key management technique that can be used during wireless sensor networks communications. For our proposal to be more effective and applicable to a large number of wireless sensor networks applications, we work on a special kind of architecture that have been proposed to cluster hierarchy of wireless sensor networks and we pick one of the most interesting protocols that have been proposed for this kind of architecture, which is LEACH. This proposal is a module of a complete solution that we are developing to cover all the aspects of wireless sensor networks communication which is labeled Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN).
- رابط البحث
- الكلمات المفتاحية
Armor-LEACH - Energy Efficient, Secure Wireless Networks Communication
- ملخص البحث
Abstract:
The use of sensor networks is increasing day by day; which offer more research topics to be discuss and modified; one of these topics is the power consumption that has to be reduced as possible, where the resources are limited; another topic is the security level that should be offer by such kind of networks. Clustered networks have been proposed in many papers to reduce the power consumption in sensor networks. LEACH is one of the most interested techniques that offer an efficient way to minimize the power consumption in sensor networks. TCCA provides LEACH with higher performance, by applying some modification to the way LEACH works. In this paper we propose a hybrid technique that offers a complete solution for routing in sensor networks. This technique reduces power consumption, increases security level, and decrease data overload for sensor networks communication.
- رابط البحث
- الكلمات المفتاحية
Routing in Sensor Networks: Performance and Security in clustered networks
- ملخص البحث
Due to high restrictions in sensor network, where the resources are limited, clustering protocols for routing organization have been proposed in much research for increasing system throughput, decreasing system delay and saving energy. Even these algorithms have proposed some levels of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper we focus on how to apply the highest possible level of security to sensor networks and at the same time increase the performance of these networks by changing the way that sensors communicate with each other.
- رابط البحث
- الكلمات المفتاحية
An Adaptive Approach for Real Time Advertising System based on User Location and Interests
- ملخص البحث
Due to the wide spread of the smart phones around the world, a special demand occurs in the mobile marketing. Real time advertising is still challenging due to its hard requirements: Tracking of customer location, knowledge of customer interests, knowledge of advertisers data and the ability to efficiently provide the customer with available advertiser’s data securely. Materials and Methods: This study introduces a comprehensive work for designing, developing and evaluation of a mobile platform for real time advertising system. This system is built by adopting well-known algorithms for each requirement concerning real time advertising system. To investigate the performance of the developed system, several experiments are conducted using a simulation program built specially for this system to measure two main factors: The missing advertisements and the delay time. Results: The simulation results show that the performance of the proposed system is very promising and revealing the importance and possibility of developing adaptive real time advertising system based on customer’s location and interest. The proposed system considered as a promising and a stable media for advertisement according to the missing advertisements and the time required for the advertisement to be received by the customer. Conclusion: This study introduce a novel system, which is built to satisfy user interests for advertisements based on his location. The system built using three subsystems to ensure its ability to produce data in real time and to handle huge traffic of subscribers and advertiser. It has also the ability to integrate different systems into it to satisfy any future requirements.
- رابط البحث
- الكلمات المفتاحية
Armor-LEACH for Wireless Sensor Network
- ملخص البحث
The use of sensor networks is increasing day by day; which offer more research topics to be discuss and modified; one of these topics is the power consumption that has to be reduced as possible, where the resources are limited; another topic is the security level that should be offer by such kind of networks. Clustered networks have been proposed in many papers to reduce the power consumption in sensor networks. LEACH is one of the most interested techniques that offer an efficient way to minimize the power consumption in sensor networks. TCCA provides LEACH with higher performance, by applying some modification to the way LEACH works. In this paper we combine two of the most powerful proposed techniques that can be applied on LEACH to reduce the power consumption and to increase the level of security.
- رابط البحث
- الكلمات المفتاحية
Connected tours for sensor networks using clustering techniques
- ملخص البحث
We consider a new problem related to data gathering in sensor networks based on multiple mobile sink elements. The problem involves the planning of a set of tours (cycles or closed paths) that cover all sensors and are connected: Each tour must be connected to at least one other tour by including a common network location. These connection points are used as data relays. The mobile element gathering data from its assigned path can leave all collected data on the designated relay point, so that it is picked up by the mobile element on the overlapping tour. This way, all data can eventually be transported to the network gateway, or any other node in the network. We formally define this new connected tour cover problem, which is a generalization of the travelling salesman problem (TSP) and therefore inherits all the known hardness properties of TSP. Then we propose a heuristic that solves this problem based on clustering, and establish its practical performance using an extensive experimental evaluation.
- رابط البحث
- الكلمات المفتاحية
Mobile communication, Clustering algorithms, Mobile computing, Planning, Wireless sensor networks, Approximation methods, Approximation algorithms
Length-Constrained and Connected Tours for Sensor Networks
- ملخص البحث
We consider a variant of the data gathering problem in sensor networks using multiple mobile elements, where each sensor must be visited with a given minimum frequency. We will construct solutions to this problem where the network is partitioned to possibly several regions, so that a single mobile element visits every node within each region. Therefore we need to partition the network and construct mobile element paths (or tours in our case) that are not too long, so that every sensor can be visited with the required frequency. Assuming the mobile elements move with some average speed, a periodic constraint for visiting a node, translates to a tour length constraint for the mobile element that visits this node. We construct solutions to this problem based on connected tour covers. We propose a divide-and-conquer heuristic to design connected tour covers for this problem and evaluate the performance using several experiments.
- رابط البحث
- الكلمات المفتاحية
Mobile communication, Approximation algorithms, Mobile computing, Approximation methods, Wireless sensor networks, Robot sensing systems, Educational institutions
ARABIC HANDWRITTEN WORD CATEGORY CLASSIFICATION USING BAG OF FEATURES.
- ملخص البحث
Human writing is highly variable and inconsistent, and this makes the offline recognition of handwritten words extremely challenging. This paper describes a novel approach that can be employed for the offline recognition of handwritten Arabic words. Through conceptualizing each word as single, inseparable objects, the proposed approach aims to recognize words in accordance with their complete shape. This paper describes the bag-of-visual-words method that has been effectively employed for the purposes of classifying images. The study consisted of four main stages. First, a set of image patches were sampled for the purposes of training, and a speeded up robust features (SURF) descriptor was then used to characterize them. Following that, the bag-of-visual-words model was employed through constructing the K-means clustering algorithm. A histogram of each whole world was developed and this operated as the image feature vector. This was employed to train the support vector machine classifier, which was then able to effectively distinguish between handwritten words. Finally, the effectiveness of the proposed method was tested using a sample of Arabic words extracted from the IFN/ENIT database and the results indicated that the bag-of-visual-words approach represents a promising method of recognizing and classifying handwritten Arabic words. The best and average recognition rates of the proposed method are 85% and 75% respectively.
- رابط البحث
- الكلمات المفتاحية
An Efficient Bit-Level Lossless Grayscale Image Compression Based on Adaptive Source Mapping.
- ملخص البحث
Image compression is an essential technique for saving time and storage space for the gigantic amount of data generated by images. This paper introduces an adaptive source-mapping scheme that greatly improves bitlevel lossless grayscale image compression. In the proposed mapping scheme, the frequency of occurrence of each symbol in the original image is computed. According to their corresponding frequencies, these symbols are sorted in descending order. Based on this order, each symbol is replaced by an 8-bit weighted fixed-length code. This replacement will generate an equivalent binary source with an increased length of successive identical symbols (0s or 1s). Different experiments using Lempel-Ziv lossless image compression algorithms have been conducted on the generated binary source. Results show that the newly proposed mapping scheme achieves some dramatic improvements in regards to compression ratios.
- رابط البحث
- الكلمات المفتاحية
Bit-Level, Lempel-Ziv Coding, Lossless Image Compression, Source Encoding
Security in wireless sensor networks: key intrusion detection module in SOOAWSN
- ملخص البحث
Due to restrictions and limited resources in wireless sensor networks, clustering for routing organization have been proposed literature to increase system throughput, decrease system delay and save energy. Although these algorithms proposed some degree of security, but because of their dynamic nature of communication, most of their security solutions are not suitable. In this paper, we propose two methods of intrusion detection techniques that can be used during wireless sensor networks communications. The proposed solution perfectly fits all kinds of wireless sensor networks that follow the clustering hierarchy distribution. In addition, it may fit many other distribution techniques. The proposed solution is integrated in a complete solution for wireless sensor network that covers all the network lifecycle from the time it deployed which is called Secure Object Oriented Architecture for Wireless Sensor Networks (SOOAWSN).
- رابط البحث
- الكلمات المفتاحية