Wireless sensor applications are susceptible to energy constraints. Most of the energy is consumed in communication between wireless nodes. Clustering and data aggregation are the two widely used strategies for reducing energy usage and increasing the lifetime of wireless sensor networks. In target tracking applications, large amount of redundant data is produced regularly. Hence, deployment of effective data aggregation schemes is vital to eliminate data redundancy. This work aims to conduct a comparative study of various research approaches that employ clustering techniques for efficiently aggregating data in target tracking applications as selection of an appropriate clustering algorithm may reflect positive results in the data aggregation process. In this paper, we have highlighted the gains of the existing schemes for node clustering based data aggregation along with a detailed discussion on their advantages and issues that may degrade the performance. Also, the boundary issues in each type of clustering technique have been analyzed. Simulation results reveal that the efficacy and validity of these clustering-based data aggregation algorithms are limited to specific sensing situations only, while failing to exhibit adaptive behavior in various other environmental conditions.
Introduction: This study aimed to investigate sex differences in age-related changes to the dentoskeletal and soft tissue profile between 12-62 years of age using a superimposition-based cephalometric method. Methods: A total of 60 subjects (27 males and 33 females) were followed longitudinally. Lateral cephalograms were obtained at ages 12 (T1), 15 (T2), 30 (T3), and 62 (T4). Of note, 46 angular and linear cephalometric variables were measured using a cranial base-registered superimposition method that corrected for age-related displacement of the Nasion and Sella landmarks. Sex differences in changes between time points were analyzed using independent-samples t tests. Results: During adolescence (12-15 years of age), males exhibited great
... Show MoreIn this work, the performance of the receiver in a quantum cryptography system based on BB84 protocol is scaled by calculating the Quantum Bit Error Rate (QBER) of the receiver. To apply this performance test, an optical setup was arranged and a circuit was designed and implemented to calculate the QBER. This electronic circuit is used to calculate the number of counts per second generated by the avalanche photodiodes set in the receiver. The calculated counts per second are used to calculate the QBER for the receiver that gives an indication for the performance of the receiver. Minimum QBER, 6%, was obtained with avalanche photodiode excess voltage equals to 2V and laser diode power of 3.16 nW at avalanche photodiode temperature of -10
... Show MoreThe present paper talks about balance between two poems which are the Nouniya for Ibn Zaidoun and Andalusia for Ahmed Shawqi. This study is not claimed to be the first of its kind but we found some artistic aspects that deserve to stop at them. This what makes the two the focus of critics and scholars as well in addition to their emphasis on the unity of the human feelings and immortality through the poet's ability to employ those feelings and emotions in a way that it can express the human soul in every time and place. That is what we believe Ibn Zaidoun had reached in his poem. Therefore, the present paper has come into the conclusion that Ibn Zaydoon's Nouniya is better than Shawqi's Andalusia due to what we got through reading and an
... Show MoreThis paper delves into some significant performance measures (PMs) of a bulk arrival queueing system with constant batch size b, according to arrival rates and service rates being fuzzy parameters. The bulk arrival queuing system deals with observation arrival into the queuing system as a constant group size before allowing individual customers entering to the service. This leads to obtaining a new tool with the aid of generating function methods. The corresponding traditional bulk queueing system model is more convenient under an uncertain environment. The α-cut approach is applied with the conventional Zadeh's extension principle (ZEP) to transform the triangular membership functions (Mem. Fs) fuzzy queues into a family of conventional b
... Show MoreBackground: The high reactivity of hydrogen peroxide used in bleaching agents have raised important questions on their potential adverse effects on physical properties of restorative materials. The purpose of this in vitro study was to evaluate the effect of in-office bleaching agents on the microhardness of a new Silorane-based restorative material in comparison to methacrylate-based restorative material. Materials and method: Forty specimens of Filtek™ P90 (3M ESPE,USA) and Filtek™ Supreme XT (3M ESPE, USA) of (8mm diameter and 3m height) were prepared. All specimens were polished with Sof-Lex disks (3M ESPE, USA). All samples were rinsed and stored in incubator 37˚C for 24 hours in DDW. Ten sample of each material were subjected to
... Show MorePurpose: The research aims to diagnose the current availability of knowledge workers characteristics and the role of these characteristics in knowledge acquision in the city of Sulaimaniya Directorate of Electricity, and to identify the differences between personal and occupational characteristics of a sample of research and its impact on the availability of such properties.Design/methodology/approach :to achieve the objectives of the research questionnaire was developed especially for it and then distributed to a sample of engineers and technicians working in the Directorate of Electricity city of Sulaimaniya, where the sample of the research (52) respondents.
Findings: the most important conclusions reached
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The aim of this study was to making an analytical study in some kinematics variables in (200) meter breaststroke swimming to first ranking in championship 2003 – Spanish. The swimming in our country still suffering from several obstruction with retarded it’s development for the better since the investigators observe the insufficiency of swimming in our country to any analytical study for the international champions, this led to no specific and scientific discovering to these advanced levels as the estimation of the value of performance from the Iraqi coaches dependent on personality observation dependent on their opinion without referring to the specific and scientific diction. The investigators dependent on several kinematics variables
... Show MoreDust and bird residue are problems impeding the operation of solar street lighting systems, especially in semi-desert areas, such as Iraq. The system in this paper was designed and developed locally using simple and inexpensive materials. The system runs automatically. It Connects to solar panels used in solar street lighting, and gets the required electricity from the same solar system. Solar panels are washed with dripping water in less than half a minute by this system. The cleaning period can also be controlled. It can also control, sensing the amount of dust the system operates. The impact of different types of falling dust on panels has also been studied. This was collected from different winds and studied their impact o
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