4,040 research outputs found

    Mengenal pasti masalah pemahaman dan hubungannya dengan latar belakang matematik, gaya pembelajaran, motivasi dan minat pelajar terhadap bab pengawalan kos makanan di Sekolah Menengah Teknik (ert) Rembau: satu kajian kes.

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    Kajian ini dijalankan untuk mengkaji hubungan korelasi antara latar belakang Matematik, gaya pembelajaran, motivasi dan minat dengan pemahaman pelajar terhadap bab tersebut. Responden adalah seramai 30 orang iaitu terdiri daripada pelajar tingkatan lima kursus Katering, Sekolah Menengah Teknik (ERT) Rembau, Negeri Sembilan. Instrumen kajian adalah soal selidik dan semua data dianalisis menggunakan program SPSS versi 10.0 untuk mendapatkan nilai min dan nilai korelasi bagi memenuhi objektif yang telah ditetapkan. Hasil kajian ini menunjukkan bahawa hubungan korelasi antara gaya pembelajaran pelajar terhadap pemahaman pelajar adalah kuat. Manakala hubungan korelasi antara latar belakang Matematik, motivasi dan minat terhadap pemahaman pelajar adalah sederhana. Nilai tahap min bagi masalah pemahaman pelajar, latar belakang Matematik, gaya pembelajaran, motivasi dan minat terhadap bab Pengawalan Kos Makanan adalah sederhana. Kajian ini mencadangkan penghasilan satu Modul Pembelajaran Kendiri bagi bab Pengawalan Kos Makanan untuk membantu pelajar kursus Katering dalam proses pembelajaran mereka

    A Contribution to Secure the Routing Protocol "Greedy Perimeter Stateless Routing" Using a Symmetric Signature-Based AES and MD5 Hash

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    This work presents a contribution to secure the routing protocol GPSR (Greedy Perimeter Stateless Routing) for vehicular ad hoc networks, we examine the possible attacks against GPSR and security solutions proposed by different research teams working on ad hoc network security. Then, we propose a solution to secure GPSR packet by adding a digital signature based on symmetric cryptography generated using the AES algorithm and the MD5 hash function more suited to a mobile environment

    Impact of malicious node on secure incentive based advertisement distribution (SIBAD) in VANET

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    Last decade has seen an increasing demand for vehicle aided data delivery. This data delivery has proven to be beneficial for vehicular communication. The vehicular network provisions safety, warning and infotainment applications. Infotainment applications have attracted drivers and passengers as it provides location based entertainment services, a value add to the traveling experience. These infotainment messages are delivered to the nearby vehicles in the form of advertisements. For every advertisement disseminated to its neighboring vehicle, an incentive is awarded to the forwarder. The incentive based earning foresee a security threat in the form of a malicious node as it hoards the incentives, thus are greedy for earning incentives. The malicious behavior of the insider has an adverse effect on the incentive based advertisement distribution approach. In this paper, we have identified the malicious nodes and analyzed its effect on incentive based earning for drivers in vehicular networks. © 2017 IEEE

    Image scoring in ad-hoc networks : an investigation on realistic settings

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    Encouraging cooperation in distributed Multi-Agent Systems (MAS) remains an open problem. Emergent application domains such as Mobile Ad-hoc Networks (MANETs) are characterised by constraints including sparse connectivity and a lack of direct interaction history. Image scoring, a simple model of reputation proposed by Nowak and Sigmund, exhibits low space and time complexity and promotes cooperation through indirect reciprocity, in which an agent can expect cooperation in the future without repeat interactions with the same partners. The low overheads of image scoring make it a promising technique for ad-hoc networking domains. However, the original investigation of Nowak and Sigmund is limited in that it (i) used a simple idealised setting, (ii) did not consider the effects of incomplete information on the mechanism’s efficacy, and (iii) did not consider the impact of the network topology connecting agents. We address these limitations by investigating more realistic values for the number of interactions agents engage in, and show that incomplete information can cause significant errors in decision making. As the proportion of incorrect decisions rises, the efficacy of image scoring falls and selfishness becomes more dominant. We evaluate image scoring on three different connection topologies: (i) completely connected, which closely approximates Nowak and Sigmund’s original setup, (ii) random, with each pair of nodes connected with a constant probability, and (iii) scale-free, which is known to model a number of real world environments including MANETs

    Simulation of a Clustering Scheme for Vehicular Ad Hoc Networks Using a DEVS-based Virtual Laboratory Environment

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    ANT 2018, The 9th International Conference on Ambient Systems, Networks and Technologies, Porto, PORTUGAL, 08-/05/2018 - 11/05/2018Protocol design is usually based on the functional models developed according to the needs of the system. In Intelligent Transport Systems (ITS), the features studied regarding Vehicular Ad hoc Networks (VANET) include self-organizing, routing, reliability, quality of service, and security. Simulation studies on ITS-dedicated routing protocols usually focus on their performance in specific scenarios. However, the evolution of transportation systems towards autonomous vehicles requires robust protocols with proven or at least guaranteed properties. Though formal approaches provide powerful tools for system design, they cannot be used for every types of ITS components. Our goal is to develop new tools combining formal tools such as Event-B with DEVS-based (Discrete Event System Specification) virtual laboratories in order to design the models of ITS components which simulation would allow proving and verifying their properties in large-scale scenarios. This paper presents the models of the different components of a VANET realized with the Virtual Laboratory Environment (VLE). We point out the component models fitting to formal modeling, and proceed to the validation of all designed models through a simulation scenario based on real-world road traffic data

    Resilient Secure Aggregation for Vehicular Networks

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    Innovative ways to use ad hoc networking between vehicles are an active research topic and numerous proposals have been made for applications that make use of it. Due to the bandwidth-limited wireless communication medium, scalability is one crucial factor for the success of these future protocols. Data aggregation is one solution to accomplish such scalability. The goal of aggregation is to semantically combine information and only disseminate this combined information in larger regions. However, the integrity of aggregated information cannot be easily verified anymore. Thus, attacks are possible resulting in lower user acceptance of applications using aggregation or, even worse, in accidents due to false information crafted by a malicious user. Therefore, it is necessary to design novel mechanisms to protect aggregation techniques. However, high vehicle mobility, as well as tight bandwidth constraints, pose strong requirements on the efficiency of such mechanisms. We present new security mechanisms for semantic data aggregation that are suitable for use in vehicular ad hoc networks. Resilience against both malicious users of the system and wrong information due to faulty sensors are taken into consideration. The presented mechanisms are evaluated with respect to their bandwidth overhead and their effectiveness against possible attacks
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