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Articles 871 - 900 of 3106
Full-Text Articles in Engineering
A Smart Wireless Sensor Network Node For Fire Detection, Wajahat Khalid, Asma Sattar, Muhammad Ali Qureshi, Asjad Amin, Mobeen Ahmed Malik, Kashif Hussain
A Smart Wireless Sensor Network Node For Fire Detection, Wajahat Khalid, Asma Sattar, Muhammad Ali Qureshi, Asjad Amin, Mobeen Ahmed Malik, Kashif Hussain
Turkish Journal of Electrical Engineering and Computer Sciences
Fires generally occur due to human carelessness and the change in environmental conditions. The uncontrolled fire results in death incidents of humans and animals as well as severe threats to the ecosystem. The preservation of the natural environment is important. The wireless sensor networks, widely used in different monitoring applications, is used in this work. For fire detection, we use flame, smoke, temperature, humidity, and light intensity sensors in our proposed network node which is low-cost, reduced-size, and power-efficient. The experiments are performed in a well-controlled real-time environment. The proposed node transmits the sensed data to the central node. The …
Early Reliability Assessment Of Component-Based Software System Using Coloredpetri Net, Amir Hosseinzadeh Mokarram, Ayaz Isazadeh, Habib Izadkhah
Early Reliability Assessment Of Component-Based Software System Using Coloredpetri Net, Amir Hosseinzadeh Mokarram, Ayaz Isazadeh, Habib Izadkhah
Turkish Journal of Electrical Engineering and Computer Sciences
Assessment of reliability in the early stages of software development from architectural models is one of the major challenges that many studies have addressed in this field in the last decade. The main drawbacks of existing methods are the following: 1) considering equal impact for all parts of the software architecture on system reliability, and 2) inability to determine the contribution of each part of the software in the system failure. This paper introduces the extended version of the colored petri net as an underlying verifiable model to evaluate the reliability of a software system. The proposed model enhances reliability …
Prioritizing Interdependent Software Requirements Using Tensor And Fuzzy Graphs, Negin Misaghian, Homayun Motameni, Mohsen Rabbani
Prioritizing Interdependent Software Requirements Using Tensor And Fuzzy Graphs, Negin Misaghian, Homayun Motameni, Mohsen Rabbani
Turkish Journal of Electrical Engineering and Computer Sciences
Owing to the special stance of prioritizing tasks in requirements engineering processes, and as the requirements are not independent in nature, considering their dependencies is essential during the prioritizing process. Although different classifications of dependency types among requirements exist, only a few approaches in the prioritization process consider such valuable data (dependency among equirements). To achieve a practical prioritization, this study proposes a method based on the effects of the requirement dependencies (increase/decrease cost of) on the value of prioritization provided by the tensor concept. Since the strengths of dependencies are also influential factors in the act of prioritization, The …
Extraction And Selection Of Statistical Harmonics Features For Electrical Appliancesidentification Using K-Nn Classifier Combined With Voting Rules Method, Fateh Ghazali, Abdenour Hacine-Gharbi, Philippe Ravier, Tayeb Mohamadi
Extraction And Selection Of Statistical Harmonics Features For Electrical Appliancesidentification Using K-Nn Classifier Combined With Voting Rules Method, Fateh Ghazali, Abdenour Hacine-Gharbi, Philippe Ravier, Tayeb Mohamadi
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we propose a novel framework for electrical appliances identification using statistical harmonic features of current signals and the use of the k-NN classifier combined with a voting rule strategy. Harmonic coefficients are computed over time using short-time Fourier series of the current signals. From these sequences of coefficients, the mean, standard deviation, skewness, and kurtosis are computed, which provide the statistical harmonic features. This framework has three novelties: (i) selecting the best combination of statistical measures in the sense of classification rate (CR); (ii) combining the k-NN classifier with the voting rule method in order to search …
Softswitch: A Centralized Honeypot-Based Security Approach Using Software-Defined Switching For Secure Management Of Vlan Networks, Muhammet Baykara, Resul Daş
Softswitch: A Centralized Honeypot-Based Security Approach Using Software-Defined Switching For Secure Management Of Vlan Networks, Muhammet Baykara, Resul Daş
Turkish Journal of Electrical Engineering and Computer Sciences
Honeypot systems are traps for intruders which simulate real systems such as web, application, and database servers used in information systems. Using these systems, unauthorized and malicious access can be efficiently detected. Honeypot is an entity which acts as a source of valued information and its behavior can be monitored. The inability or difficulty of intrusion detection is a serious security problem in networks including virtual local area network (VLAN). According to the literature, the use of honeypots for intrusion detection and prevention in networks including VLAN is strongly recommended. In this paper, in order to provide security and to …
Increasing Bluetooth Low Energy Communication Efficiency By Presetting Protocol Parameters, Dusan Hatvani, Dominik Macko
Increasing Bluetooth Low Energy Communication Efficiency By Presetting Protocol Parameters, Dusan Hatvani, Dominik Macko
Turkish Journal of Electrical Engineering and Computer Sciences
Standard protocols are important regarding the compatibility of devices provided by different vendors. However, specific applications have various requirements and do not always need all features offered by standard protocols, making them inefficient. This paper focuses on standard Bluetooth Low Energy modifications, reducing control overhead for the intended healthcare application. Specifically, the connection establishment, device pairing, and connection parameter negotiations have been targeted. The simulation-based experiments showed over 20 times reduction of control-overhead time preceding a data transmission. It does not just directly increase the energy efficiency of communication; it also prolongs the time for sensor-based end devices to spend …
Lightweight Signature Scheme To Protect Intellectual Properties Of Internet Of Things Applications In System On Chip Field-Programmable Gate Arrays, Kokila Jagadeesh, Ramasubramanian Natarajan
Lightweight Signature Scheme To Protect Intellectual Properties Of Internet Of Things Applications In System On Chip Field-Programmable Gate Arrays, Kokila Jagadeesh, Ramasubramanian Natarajan
Turkish Journal of Electrical Engineering and Computer Sciences
Billions of smart objects in the edge devices offer advanced connectivity to networks which increase the security and complexity of the Internet of things (IoT) applications. To make such entities smarter heterogeneous intellectual property (IP) cores from multiple service providers are reused in system on chip platform. Enabling both chip and IP protection at post fabrication level is imperative. The IoT-based IP cores are signed with the hybrid physical unclonable function and finite state machine model to protect from cloning, misuse, unauthorized user access, and physical attacks. The extended finite-state machine is used to verify the signature, which reduces the …
Solving Vehicle Routing Problem For Multistorey Buildings Using Iterated Local Search, Osman Gökalp, Aybars Uğur
Solving Vehicle Routing Problem For Multistorey Buildings Using Iterated Local Search, Osman Gökalp, Aybars Uğur
Turkish Journal of Electrical Engineering and Computer Sciences
Vehicle routing problem (VRP) which is a well-known combinatorial optimisation problem that has many applications used in industry is also a generalised form of the travelling salesman problem. In this study, we defined and formulated the VRP in multistorey buildings (Multistorey VRP) for the first time and proposed a solving method employing iterated local search metaheuristic algorithm. This variant of VRP has a great potential for turning the direction of optimisation research and applications to the vertical cities area as well as the horizontal ones. Routes of part picking or placing vehicles/humans in multistorey plants can be minimised by this …
Abc-Based Stacking Method For Multilabel Classification, Weimin Ding, Shengli Wu
Abc-Based Stacking Method For Multilabel Classification, Weimin Ding, Shengli Wu
Turkish Journal of Electrical Engineering and Computer Sciences
Multilabel classification is a supervised learning problem wherein each individual instance is associated with multiple labels. Ensemble methods are effective in managing multilabel classification problems by creating a set of accurate, diverse classifiers and then combining their outputs to produce classifications. This paper presents a novel stacking-based ensemble algorithm, ABC-based stacking, for multilabel classification. The artificial bee colony algorithm, along with a single-layer artificial neural network, is used to find suitable meta-level classifier configurations. The optimization goal of the meta-level classifier is to maximize the average accuracy of classification of all the instances involved. We run an experiment on 10 …
Selective Word Encoding For Effective Text Representation, Savaş Özkan, Akin Özkan
Selective Word Encoding For Effective Text Representation, Savaş Özkan, Akin Özkan
Turkish Journal of Electrical Engineering and Computer Sciences
Determining the category of a text document from its semantic content is highly motivated in the literature and it has been extensively studied in various applications. Also, the compact representation of the text is a fundamental step in achieving precise results for the applications and the studies are generously concentrated to improve its performance. In particular, the studies which exploit the aggregation of word-level representations are the mainstream techniques used in the problem. In this paper, we tackle text representation to achieve high performance in different text classification tasks. Throughout the paper, three critical contributions are presented. First, to encode …
Cache Pressure-Aware Caching Scheme For Content-Centric Networking, Xi Luo, Ying An
Cache Pressure-Aware Caching Scheme For Content-Centric Networking, Xi Luo, Ying An
Turkish Journal of Electrical Engineering and Computer Sciences
Content centric networking (CCN) is a new networking paradigm to meet the growing demand for content access in the future. Because of its important role in accelerating content retrieval and reducing network transmission load, in-network caching has become one of the core technologies in CCN and has attracted wide attention. The existing caching schemes often lack sufficient consideration of node cache status and the temporal validity of user requests, and thus the cache efficiency of the network is greatly reduced. In this paper, a cache pressure-aware caching scheme is proposed, which comprehensively takes into account various factors such as content …
Word Sense Disambiguation Using Semantic Kernels With Class-Based Term Values, Ayşe Berna Altinel, Murat Can Gani̇z, Bi̇lge Şi̇pal, Eren Can Erkaya, Onur Can Yücedağ, Muhammed Ali̇ Doğan
Word Sense Disambiguation Using Semantic Kernels With Class-Based Term Values, Ayşe Berna Altinel, Murat Can Gani̇z, Bi̇lge Şi̇pal, Eren Can Erkaya, Onur Can Yücedağ, Muhammed Ali̇ Doğan
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, we propose several semantic kernels for word sense disambiguation (WSD). Our approaches adapt the intuition that class-based term values help in resolving ambiguity of polysemous words in WSD. We evaluate our proposed approaches with experiments, utilizing various sizes of training sets of disambiguated corpora (SensEval). With these experiments we try to answer the following questions: 1.) Do our semantic kernel formulations yield higher classification performance than traditional linear kernel?, 2.) Under which conditions a kernel design performs better than others?, 3.) Does the addition of class labels into standard term-document matrix improve the classification accuracy?, 4.) Is …
Assessment Of Techno-Economic Benefits For Smart Charging Scheme Of Electric Vehicles In Residential Distribution System, Kumari Kasturi, Manas Ranjan Nayak
Assessment Of Techno-Economic Benefits For Smart Charging Scheme Of Electric Vehicles In Residential Distribution System, Kumari Kasturi, Manas Ranjan Nayak
Turkish Journal of Electrical Engineering and Computer Sciences
Connecting multiple electric vehicles (EVs) to a power system network for the purpose of charging has major setbacks like decrease in power quality, instability in voltage profile, and increase in power losses and thus electricity price. This paper focuses on devising an optimal charging scheme to reduce the negative impacts of EVs' presence in the distribution network by limiting the charging process to only off-peak demand periods when the electricity price is comparatively lower. The salp swarm algorithm, an efficient, fast, and reliable optimization technique, is used to obtain the optimal locations for the EVs and their charging schedule in …
Antenna Selection And Transmission Power For Energy Efficiency In Downlink Massive Mimo Systems, Adeeb Salh, Lukman Audah, Nor Shahida Mohd Shah, Shipun Anuar Hamzah, Hasan Saeed Mir
Antenna Selection And Transmission Power For Energy Efficiency In Downlink Massive Mimo Systems, Adeeb Salh, Lukman Audah, Nor Shahida Mohd Shah, Shipun Anuar Hamzah, Hasan Saeed Mir
Turkish Journal of Electrical Engineering and Computer Sciences
Massive multiinput-multioutput (M-MIMO) systems are crucial for maximizing energy efficiency (EE) in fifth-generation (5G) wireless networks. A M-MIMO system's achievable high data rate is highly related to the number of antennas, but increasing the number of antennas the system raises energy consumption. In this paper, we derive ergodic EE based on the optimal transmit power and joint optimization antenna selection (AS) with impact pilot reuse sequences (PRSs). We apply Newton's method and the Lagrange multiplier to derive jointly optimized AS and optimal transmission power under the effect of PRSs. The proposed algorithm prevents repeated searching for joint optimal AS and …
Lung Segmentation In Chest Radiographs Using Fully Convolutional Networks, Rahul Hooda, Ajay Mittal, Sanjeev Sofat
Lung Segmentation In Chest Radiographs Using Fully Convolutional Networks, Rahul Hooda, Ajay Mittal, Sanjeev Sofat
Turkish Journal of Electrical Engineering and Computer Sciences
Automated segmentation of medical images that aims at extracting anatomical boundaries is a fundamental step in any computer-aided diagnosis (CAD) system. Chest radiographic CAD systems, which are used to detect pulmonary diseases, first segment the lung field to precisely define the region-of-interest from which radiographic patterns are sought. In this paper, a deep learning-based method for segmenting lung fields from chest radiographs has been proposed. Several modifications in the fully convolutional network, which is used for segmenting natural images to date, have been attempted and evaluated to finally evolve a network fine-tuned for segmenting lung fields. The testing accuracy and …
Approximation Of Planar Curves, Malik Zawwar Hussain, Ayesha Shakeel, Maria Hussain
Approximation Of Planar Curves, Malik Zawwar Hussain, Ayesha Shakeel, Maria Hussain
Turkish Journal of Electrical Engineering and Computer Sciences
In the present article, we have developed the $G^{2}$-approximation scheme for planar curves arising in science, engineering, computer-aided design, computer-aided manufacturing, and many other fields. The obtained results reveal that the proposed method is a significant addition to the approximation of planar curves. The method is illustrated using different numerical examples. The smaller absolute error confirms the applicability and efficiency of the proposed method.
On Spectral Analysis Of The Internet Delay Space And Detecting Anomalous Routing Paths, Gonca Gürsun
On Spectral Analysis Of The Internet Delay Space And Detecting Anomalous Routing Paths, Gonca Gürsun
Turkish Journal of Electrical Engineering and Computer Sciences
Latency is one of the most critical performance metrics for a wide range of applications. Therefore, it is important to understand the underlying mechanisms that give rise to the observed latency values and diagnose the ones that are unexpectedly high. In this paper, we study the Internet delay space via robust principal component analysis (RPCA). Using RPCA, we show that the delay space, i.e. the matrix of measured round trip times between end hosts, can be decomposed into two components: the estimated latency between end hosts with respect to the current state of the Internet and the inflation on the …
Measurement Of Network-Based And Random Meetings In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud
Measurement Of Network-Based And Random Meetings In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud
Turkish Journal of Electrical Engineering and Computer Sciences
Social networks are created by the underlying behavior of the actors involved in them. Each actor has interactions with other actors in the network and these interactions decide whether a social relationship should develop between them. Such interactions may occur due to meeting processes such as chance-based meetings or network-based (choice) meetings. Depending upon which of these two types of interactions plays a greater role in creation of links, a social network shall evolve accordingly. This evolution shall result in the social network obtaining a suitable structure and certain unique features. The aim of this work is to determine the …
Refugees' Social Media Activities In Turkey: A Computational Analysis And Demonstration Method, Muhammed Abdullah Bülbül, Salah Haj Ismail
Refugees' Social Media Activities In Turkey: A Computational Analysis And Demonstration Method, Muhammed Abdullah Bülbül, Salah Haj Ismail
Turkish Journal of Electrical Engineering and Computer Sciences
This study performs a data analysis on refugees in Turkey based on their social media activities. In order to achieve this, we first propose a method to find their relevant public accounts and collect their activities generating a dataset. Then, we perform spatial and temporal analysis over this dataset to shed light on the most important topics and events discussed in social networks. We present the results graphically for ease of understanding and comparison. Our results indicate that we can reveal the most shared topics over a specific time and place as well as the change of pattern in refugees' …
A Novel Design Of An Electromagnetically Levitated Vibrational Viscometer For Biomedical And Clinical Applications, Ali̇ Akpek
Turkish Journal of Electrical Engineering and Computer Sciences
Accurate determination of the viscosity behavior of fluids is extremely important, especially for biomedical and clinical applications. For example, blood viscosity is used to detect cardiovascular diseases in patients. Like blood, all body fluids and biochemical solvents used in biomedical studies are very limited resources. Therefore, a viscometer that is especially focused for biomedical and clinical applications should have the ability to obtain viscosity results from a reservoir as small as possible, in a range as wide as possible and in a period of time as short as possible. The measurements must be accurate even when the fluid temperatures shift …
Classification Of Generic System Dynamics Model Outputs Via Supervised Time Series Pattern Discovery, Mert Edali, Mustafa Gökçe Baydoğan, Gönenç Yücel
Classification Of Generic System Dynamics Model Outputs Via Supervised Time Series Pattern Discovery, Mert Edali, Mustafa Gökçe Baydoğan, Gönenç Yücel
Turkish Journal of Electrical Engineering and Computer Sciences
System dynamics (SD) is a simulation-based approach for analyzing feedback-rich systems. An ideal SD modeling cycle requires evaluating the qualitative pattern characteristics of a large set of time series model output for testing, validation, scenario analysis, and policy analysis purposes. This traditionally requires expert judgement, which limits the extent of experimentation due to time constraints. Although time series recognition approaches can help to automate such an evaluation, utilization of them has been limited to a hidden Markov model classifier, namely the Indirect Structure Testing Software (ISTS) algorithm. Despite being used within several automated model-analysis tools, ISTS has several shortcomings. In …
Graph Analysis Of Network Flow Connectivity Behaviors, Hangyu Hu, Xuemeng Zhai, Mingda Wang, Guangmin Hu
Graph Analysis Of Network Flow Connectivity Behaviors, Hangyu Hu, Xuemeng Zhai, Mingda Wang, Guangmin Hu
Turkish Journal of Electrical Engineering and Computer Sciences
Graph-based approaches have been widely employed to facilitate in analyzing network flow connectivity behaviors, which aim to understand the impacts and patterns of network events. However, existing approaches suffer from lack of connectivity-behavior information and loss of network event identification. In this paper, we propose network flow connectivity graphs (NFCGs) to capture network flow behavior for modeling social behaviors from network entities. Given a set of flows, edges of a NFCG are generated by connecting pairwise hosts who communicate with each other. To preserve more information about network flows, we also embed node-ranking values and edge-weight vectors into the original …
Design And Fabrication Of A Dual-Polarized, Dual-Band Reflectarray Using Optimal Phase Distribution, Iman Aryanian, Arash Ahmadi, Mehdi Rabbani, Sina Hassibi, Majid Karimipour
Design And Fabrication Of A Dual-Polarized, Dual-Band Reflectarray Using Optimal Phase Distribution, Iman Aryanian, Arash Ahmadi, Mehdi Rabbani, Sina Hassibi, Majid Karimipour
Turkish Journal of Electrical Engineering and Computer Sciences
Two main factors limiting the reflectarray bandwidth are different phase slopes versus the frequency at every point on the aperture and the phase limitation of comprising elements at different frequencies. Considering these two factors, a novel design method is proposed to implement a dual-band, dual-polarized reflectarray antenna in X and Ku bands. An optimization algorithm is adopted to find the optimum phase for each unit cell on the reflectarray aperture. The best geometrical parameters of the phasing elements are suggested based on the phase variation of the element versus frequency and the element position with respect to the antenna feed. …
A New Computer-Controlled Platform For Adc-Based True Random Number Generator And Its Applications, Selçuk Coşkun, İhsan Pehli̇van, Aki̇f Akgül, Bi̇lal Gürevi̇n
A New Computer-Controlled Platform For Adc-Based True Random Number Generator And Its Applications, Selçuk Coşkun, İhsan Pehli̇van, Aki̇f Akgül, Bi̇lal Gürevi̇n
Turkish Journal of Electrical Engineering and Computer Sciences
The basis of encryption techniques is random number generators (RNGs). The application areas of cryptology are increasing in number due to continuously developing technology, so the need for RNGs is increasing rapidly, too. RNGs can be divided into two categories as pseudorandom number generator (PRNGs) and true random number generator (TRNGs). TRNGs are systems that use unpredictable and uncontrollable entropy sources and generate random numbers. During the design of TRNGs, while analog signals belonging to the used entropy sources are being converted to digital data, generally comparators, flip-flops, Schmitt triggers, and ADCs are used. In this study, a computer-controlled new …
Cost-Effective Telemetry For Energy Network Of An Electricity Distribution Company: Part I, Asim Zaheer Ud Din, Yasar Ayaz, Mian Ilyas Ahmad Ahmad, Momena Hasan, Salman Masaud, Naveed Muhammad
Cost-Effective Telemetry For Energy Network Of An Electricity Distribution Company: Part I, Asim Zaheer Ud Din, Yasar Ayaz, Mian Ilyas Ahmad Ahmad, Momena Hasan, Salman Masaud, Naveed Muhammad
Turkish Journal of Electrical Engineering and Computer Sciences
We present a novel application of radio frequency wireless mesh network and general packet radio service technologies in a telemetry solution to measure power flow in the energy network of an electricity distribution company. The telemetry solution utilizes some selected circuits of grid stations and calculates total power consumed, total power imported, and total power exported by the distribution company. The selection of circuits for sensors installation is the key for reducing solution cost as compared to the case when sensors are installed on all the power output points. The framework involves installation of specially developed energy sensors (smart energy …
Prey-Predator Algorithm For Discrete Problems: A Case For Examination Timetabling Problem, Surafel Luleseged Tilahun
Prey-Predator Algorithm For Discrete Problems: A Case For Examination Timetabling Problem, Surafel Luleseged Tilahun
Turkish Journal of Electrical Engineering and Computer Sciences
The prey-predator algorithm is a metaheuristic algorithm inspired by the interaction between a predator and its prey. Initial solutions are put into three categories: the better performing solution as the best prey, the worst performing solution as a predator, and the rest as ordinary prey. The best prey totally focuses on exploiting its neighborhood while the predator explores the search space searching for a promising region in the search space. The ordinary prey will be affected by these two extreme search behaviors of exploration and exploitation. The algorithm has been tested and found to be effective in solving different problems …
Optimal Range Of Loading For Operating A Fixed-Speed Wind Turbine Using A Self-Excited Induction Generator, Nassi̇m Iqteit, Gül Kurt, Beki̇r Çakir
Optimal Range Of Loading For Operating A Fixed-Speed Wind Turbine Using A Self-Excited Induction Generator, Nassi̇m Iqteit, Gül Kurt, Beki̇r Çakir
Turkish Journal of Electrical Engineering and Computer Sciences
In the present study, a new strategy of analysis was used to determine the optimal interval of a single-phase resistive load to operate a fixed-speed wind turbine. The essence of this optimal range is to enable the generator to have stable voltages and current balances, large power, and an acceptable frequency range, and also mitigate generator overheating. The generator windings and excitation capacitances were prepared according to the C-2C connection scheme with suitable values of excitation capacitances. The admittance matrix of the system was based on positive and negative sequence generator voltages and was calculated by symmetrical components theory. The …
Characterization Of A High-Speed Radio-Frequency Sampling And Demultiplexing Circuit Based On The Cascade Connection Of Pin Photodiodes, Carlos Villa Angulo, Ivan O. Hernandez-Fuentes, Ricardo Morales-Carbajal, Rafael Villa-Angulo, Jose R. Villa-Angulo
Characterization Of A High-Speed Radio-Frequency Sampling And Demultiplexing Circuit Based On The Cascade Connection Of Pin Photodiodes, Carlos Villa Angulo, Ivan O. Hernandez-Fuentes, Ricardo Morales-Carbajal, Rafael Villa-Angulo, Jose R. Villa-Angulo
Turkish Journal of Electrical Engineering and Computer Sciences
Herein, we apply theoretical models to characterize the transfer function and frequency response of a complex optoelectronic circuit that comprises a primary ultrafast sampling circuit followed by a cascade connection of \textsl{N} demultiplexing stages. The successive radio-frequency optoelectronic samplers were based on the cascade connection of positive-intrinsic-negative-photodiodes (PIN-PDs). We developed a procedure to calculate the principal design parameters that allows us to use optical power for each sampling and demultiplexing stage, such that the circuit can be designed based on the application requirements. The results obtained from the theoretical models were compared with the measurements obtained from the 2.5 GS …
Tapu: Test And Pick Up-Based $K$-Connectivity Restoration Algorithm For Wireless Sensor Networks, Vahi̇d Khali̇lpour Akram, Orhan Dağdevi̇ren
Tapu: Test And Pick Up-Based $K$-Connectivity Restoration Algorithm For Wireless Sensor Networks, Vahi̇d Khali̇lpour Akram, Orhan Dağdevi̇ren
Turkish Journal of Electrical Engineering and Computer Sciences
A $k$-connected wireless sensor network remains connected if any $k$-1 arbitrary nodes stop working. The aim of movement-assisted $k$-connectivity restoration is to preserve the $k$-connectivity of a network by moving the nodes to the necessary positions after possible failures in nodes. This paper proposes an algorithm named TAPU for $k$-connectivity restoration that guarantees the optimal movement cost. Our algorithm improves the time and space complexities of the previous approach (MCCR) in both best and worst cases. In the proposed algorithm, the nodes are classified into safe and unsafe groups. Failures of safe nodes do not change the $k$ value of …
Design And Development Of A Stewart Platform Assisted And Navigated Transsphenoidal Surgery, Selçuk Ki̇zi̇r, Zafer Bi̇ngül
Design And Development Of A Stewart Platform Assisted And Navigated Transsphenoidal Surgery, Selçuk Ki̇zi̇r, Zafer Bi̇ngül
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, technical details of a Stewart platform (SP) based robotic system as an endoscope positioner and holder for endoscopic transsphenoidal surgery are presented. Inverse and forward kinematics, full dynamics, and the Jacobian matrix of the robotic system are derived and simulated in MATLAB/Simulink. The required control structure for the trajectory and position control of the SP is developed and verified by several experiments. The robotic system can be navigated using a six degrees of freedom (DOF) joystick and a haptic device with force feedback. Position and trajectory control of the SP in the joint space is achieved using …