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"In recent times, the demand for the real time audio and video applications in wireless networks is very high due to widespread use of latest wireless communication technologies. Many of these applications require different Quality of Service (QoS) in terms of delay and throughput in the resource constrained wireless networks. In order to handle the resources effectively and to increase the QoS, proper packet scheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm which combines Strict Priority Queuing (SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications such as voice and video in the SPQ and treat them preferentially over other traffic by allowing the application to be processed and sent first from the SPQ. In this paper, an Enhanced LLQ (ELLQ) is proposed. An additional SPQ is introduced for scheduling the video applications separately along with the dedicated SPQ for voice applications. The performance of the proposed algorithm is compared with other existing algorithms through simulations using the OPNET modeler. Simulation and Statistical results show that the proposed algorithm has given 1.5 times performance improvement in terms of throughput and delay than the existing algorithms for the real time audio and video applications."

"In recent times, the demand for the real time audio and video applications in wireless networks is very high due to widespread use of latest wireless communication technologies. Many of these applications require different Quality of Service (QoS) in terms of delay and throughput in the resource constrained wireless networks. In order to handle the resources effectively and to increase the QoS, proper packet scheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm which combines Strict Priority Queuing (SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications such as voice and video in the SPQ and treat them preferentially over other traffic by allowing the application to be processed and sent first from the SPQ. In this paper, an Enhanced LLQ (ELLQ) is proposed. An additional SPQ is introduced for scheduling the video applications separately along with the dedicated SPQ for voice applications. The performance of the proposed algorithm is compared with other existing algorithms through simulations using the OPNET modeler. Simulation and Statistical results show that the proposed algorithm has given 1.5 times performance improvement in terms of throughput and delay than the existing algorithms for the real time audio and video applications."

"Time synchronization is a vital process in wireless sensor networks, where energy sources are highly limited. In this work, we propose a broadcast-based skew correction technique that will improve both the accuracy and the lifetime of any time synchronization protocol that only corrects time offsets among sensor nodes. Using time information transmitted periodically by the root node, each client node can compensate its software clock frequency in real time after an initial offset correction. The experimental results show that a clock skew below 0.05 us/s can be consistently achieved with appropriate compensation parameters after the correction process is stabilized."

"The low-cost Wireless Sensor Network (WSN) consists of small battery powered devices called sensors, with limited energy capacity. Once deployed, accessibility to any sensor node for maintenance and battery replacement is not feasible due to the spatial scattering of the nodes. This will lead to an unreliable, limited lifetime and a poor connectivity network. In this paper a novel bio-inspired cluster-based deployment algorithm is proposed for energy optimization of the WSN and ultimately to improve the network lifetime. In the cluster initialization phase, a single cluster is formed with a single cluster head at the center of the sensing terrain. The second phase is for optimum cluster formation surrounding the inner cluster, based on swarming bees and a piping technique. Each cluster member distributes its data to its corresponding cluster head and the cluster head communicates with the base station, which reduces the communication distance of each node. The simulation results show that, when compared with other clustering algorithms, the proposed algorithm can significantly reduce the number of clusters by 38% and improve the network lifetime by a factor of 1/4."

"Data clustering is one of the major areas in data mining. The bisecting clustering algorithm is one of the most widely used for high dimensional dataset. But its performance degrades as the dimensionality increases. Also, the task of selection of a cluster for further bisection is a challenging one. To overcome these drawbacks, we developed a novel partitional clustering algorithm called a HB-K-Means algorithm (High dimensional Bisecting K-Means). In order to improve the performance of this algorithm, we incorporate two constraints, such as a stability-based measure and a Mean Square Error (MSE) resulting in CHB-K-Means (Constraint-based High dimensional Bisecting K-Means) algorithm. The CHB-K-Means algorithm generates two initial partitions. Subsequently, it calculates the stability and MSE for each partition generated. Inference techniques are applied on the stability and MSE values of the two partitions to select the next partition for the re-clustering process. This process is repeated until K number of clusters is obtained. From the experimental analysis, we infer that an average clustering accuracy of 75% has been achieved. The comparative analysis of the proposed approach with the other traditional algorithms shows an achievement of a higher clustering accuracy rate and an increase in computation time."

"ABSTRAKPerkembangan teknologi dan transformasi sosial-ekonomi telah menyebabkan bisnis jaringan seluler 5G mengalami perubahan, sehingga jaringan seluler 5G diharapkan dapat mengirim informasi dengan cepat dan mendukung kasus penggunaan yang banyak bermunculan dari berbagai aplikasi. Salah satu kasus penggunaan pada jaringan 5G adalah massive Machine Type Communication (MTC). Salah satu aplikasi massive MTC adalah jaringan sensor nirkabel (JSN). Tantangan bagi jaringan seluler 5G ini adalah bagaimana memodelkan arsitektur/topologi untuk mendukung JSN dan bagaimana mengatasi masalah efisiensi konsumsi energi di JSN. Untuk menjawab tantangan ini, maka diterapkan sistem HAP yang terintegrasi JSN dan menggunakan protokol routing Low Energy Adaptive Clustering Hierarchy. Sistem HAP dirancang untuk digunakan di ketinggian 20 km dengan topologi tanpa dan dengan clustering, menggunakan 1.000 node sensor. Sistem ini telah disimulasikan dengan menggunakan MATLAB. Simulasi dilakukan untuk melihat konsumsi energi, jumlah node yang mati dan rata-rata total paket yang dikirim ke HAP untuk topologi tanpa dan dengan clustering. Dari serangkaian simulasi, terlihat bahwa topologi dengan clustering dapat mengurangi konsumsi energi dan jumlah node yang mati, sekaligus meningkatkan total paket yang dikirimkan ke HAP."

"Telecommunication technology is very fast developing.One of them is mobile phone technology.The question is how to detect mobile phone position when it is used,especially in emergency....."

"Inhibition is one of themechanisms used for mitigating the metallic corrosion, particularly in an acid environment. The present work aims toinvestigate theinhibiting effect of N-benzyl-N/-phenyl thiourea (BPTU) on thecorrosion of low carbon steel in a 0.1 M hydrochloric acid (HCl) solution using a Tafelextrapolation and linear polarization techniques. The study reveals that BPTUacts as an excellent anodic inhibitor for low carbon steel in a HClsolution. The protective efficiency of the compound was found to be more than97% even at higher temperatures. The study demonstrated that BPTU gets adsorbedon the steel surface, following Temkin?s adsorption isotherm and the inhibitionis controlled by a chemisorptionmechanism. The investigation shows that the results obtained from the Tafelextrapolation and linear polarization techniques for the corrosion of mildsteel in HCl medium were in good agreement. The influence of temperatures andconcentrations of BPTU on the corrosion of low carbon steel are alsoexamined in the present work."

"In this study, modeling of the crossing point temperature (CPT) phenomenon in the low-temperature oxidation of coal was carried out using COMSOL Multiphysics®. Low-temperature oxidation can lead to spontaneous combustion of coal stockpiles. The CPT phenomenon was modeled with the kinetics data obtained from a prior laboratory experimental study. The coupling of the heat-transfer phenomenon through conduction and convection determined the thermal evolution model. In this case, coal received the initial heat of the oven temperature increases. As the coal temperature rose, the heat generated from oxidation was released into the environment via conduction and convection. Meanwhile, oxidation products and oxygen were transferred by convection and diffusion. The effects of moisture and the humidity were not considered. The outcomes of modeling were validated through comparison with the results of experimental tests, and the modeling result agreed well with the experiment tests, with temperature deviations of about 0.9%. The effects of airflow rate, oxygen concentration, porosity, and the initial temperature on low-temperature coal oxidation were also examined."