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"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."

"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 WirelessSensor Network(WSN) consists of small battery powered devices called sensors, with limitedenergy capacity. Once deployed, accessibility to any sensor node for maintenance and battery replacement is not feasibledue 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-baseddeployment algorithm is proposed for energy optimization of the WSNand ultimately to improve the network lifetime. In the cluster initializationphase, a singlecluster is formed with a single cluster head at the center of the sensing terrain. Thesecond phase is for optimum cluster formation surroundingthe inner cluster, based on swarming bees and a piping technique. Each cluster member distributesits data to its corresponding cluster head and the cluster head communicateswith the base station, which reduces the communication distance of each node. The simulationresults show that, whencompared with other clustering algorithms, the proposed algorithm can significantly reducethe number of clusters by 38% and improve the network lifetime by a factor of1/4."

"In recent times, thedemand for the real time audio and video applications in wireless networks isvery high due to widespread use of latest wireless communication technologies.Many of these applications require different Quality of Service (QoS) in termsof delay and throughput in the resource constrained wireless networks. In orderto handle the resources effectively and to increase the QoS, proper packetscheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm whichcombines Strict Priority Queuing(SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications suchas voice and video in the SPQ and treat them preferentially over other trafficby 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 applicationsseparately along with the dedicated SPQ for voice applications. The performanceof the proposed algorithm is compared with other existing algorithms throughsimulations using the OPNET modeler. Simulation and Statistical results showthat the proposed algorithm has given 1.5 times performance improvement interms of throughput and delay than the existing algorithms for the real timeaudio and video applications."

"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."

"The routine dailyactivities that tend to be sedentary and repetitive may cause severe healthproblems. This issue has encouraged researchers to design a system to detectand record people activities in real time and thus encourage them to do morephysical exercise. By utilizing sensors embedded in a smartphone, many researchstudies have been conducted to try to recognize user activity. The most commonsensors used for this purpose are accelerometers and gyroscopes; however, wefound out that a gravity sensor has significant potential to be utilized aswell. In this paper, we propose a novel method to recognize activities usingthe combination of an accelerometer and gravity sensor. We design a simplehierarchical system with the purpose of developing a more energy efficientapplication to be implemented in smartphones. We achieved an average of 95% forthe activity recognition accuracy, and we also succeed at proving that our workis more energy efficient compared to other works."

"Cylindrical uranium dioxide pellets, which are the main components for nuclear fuel elements in light water reactors, should have a high density profile, a uniform shape, and a minimum standard quality for their safe use as a reactor fuel component. The quality of green pellets is conventionally monitored by laboratory measurement of the physical pellet characteristics; however, this conventional classification method shows some drawbacks, such as difficult usage, low accuracy, and high time consumption. In addition, the method does not address the non-linearity and complexity of the relationship between pellet quality variables and pellet quality. This paper presents the development and application of a modified Radial Basis Function neural network (RBF NN) as an automatic classification system for green pellet quality. The weight initialization of the neural networks in this modified RBF NN is calculated through an orthogonal least squared method, and in conjunction with the use of a sigmoid activation function on its output neurons. Experimental data confirm that the developed modified RBF NN shows higher recognition capability when compared with that of the conventional RBF NNs. Further experimental results show that optimizing the quality classification problem space through eigen decomposition method provides a higher recognition rate with up to 98% accuracy."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 Ω/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"This book provides an overview of the latest research and development of new technologies for cognitive radio, mobile communications, and wireless networks. The contributors discuss the research and requirement analysis and initial standardization work towards 5G cellular systems and the capacity problems it presents. They show how cognitive radio, with the capability to flexibly adapt its parameters, has been proposed as the enabling technology for unlicensed secondary users to dynamically access the licensed spectrum owned by legacy primary users on a negotiated or an opportunistic basis. They go on to show how cognitive radio is now perceived in a much broader paradigm that will contribute to solve the resource allocation problem that 5G requirements raise. The chapters represent hand-selected expanded papers from EAI sponsored and hosted conferences such as the 12th EAI International Conference on Mobile and Ubiquitous Systems, the 11th EAI International Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, the 10th International Conference on Cognitive Radio Oriented Wireless Networks, the 8th International Conference on Mobile Multimedia Communications, and the EAI International Conference on Software Defined Wireless Networks and Cognitive Technologies for IoT."