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"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."

"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."

"Assessing trustworthiness of social media posts is increasingly important, as the number of online users and activities grows. Current deploying assessment systems measure post trustworthiness as credibility. However, they measure the credibility of all posts, indiscriminately. The credibility concept was intended for news types of posts. Labeling other types of posts with credibility scores may confuse the users. Previous notable works envisioned filtering out non-newsworthy posts before credibility assessment as a key factor towards a more efficient credibility system. Thus, we propose to implement a topic-based supervised learning approach that uses Term Frequency-Interim Document Frequency (TF-IDF) and cosine similarity for filtering out the posts that do not need credibility assessment. Our experimental results show that about 70% of the proposed filtering suggestions are agreed by the users. Such results support the notion of newsworthiness, introduced in the pioneering work of credibility assessment. The topic-based supervised learning approach is shown to provide a viable social network filter."

"Understanding 5G from aperspective of innovation is to explore both technical research and development(R&D) and non-technical issues. While 4G has been considered as anincremental innovation from its predecessors (3G and 2G), design features andkey technologies have indicated 5G as a disruptive innovation. Consequently, 5Gwill create new market values, in which new services and applications willemerge in unexpected ways. Hence, it is predicted that policy makers will facesignificant challenges concerning 5G implementation in their respectivecountries. This paper aims to investigate the challenges to standards andregulations at a country level. The discussion begins with the challengesbecause of the emergence of non-human markets as well as the complexity ofmulti-device technological platforms. Due to anticipated massive cloud-basedapplications, security issues of cloud-based applications will be a subsequentchallenge for national policy makers. Finally, as 5G may require varioussupporting technologies, the challenge for the policy maker is also to triggernational development of local standards."

"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."

"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."

"Flotation is animportant process in mining industries. This process employs the bubble andhydrophobic properties of a particle to separate valuable mining particles fromimpurities. The most important phenomenon in determining flotation efficiencyis the bubble-particle interaction; therefore, understanding this phenomenon isvery important. The aim of this research is to study the mechanism ofbubble-particle interactions with and without the addition of a collector. Theexperimental setup consists of a water container, bubble generator, particlefeeding system, and an image capturing system. The water container is made fromtransparent material of a size large enough so that the wall?s effects onbubbles and particles can be neglected. Air bubbles are generated by a bubblegenerator which consists of a small nozzle and programmable syringe pump. Ahigh speed video camera and halogen lamp backlighting system are used as imagecapturing devices. Observation of the images reveals that bubble-particleinteraction follows the stages of bubble-particle collision, particle attachedto the bubble, and particle detached from the bubble. The addition of acollector to the liquid affects the bubble-particle interactions."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."