Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2025Scopus SJRQ1Quantification of Honey Adulteration Using a Planar Microstrip Metamaterial-Motivated Sensor and Software-Defined Radio
Cem Hasar, Ugur; Hasar, Hafize; Kaya, Yunus; Ozturk, Hamdullah; Korkmaz, Huseyin; Kosunalp, Selahattin; Iliev, Teodor; Tariqul Islam, Mohammad; Nayyeri, Vahid; Mustafa Ramahi, Omar
This work presents the application of a planar microstrip metamaterial (MM)-motivated sensor in the form of a split-ring resonator (SRR) for the detection and quantification of water adulteration in honey samples. The proposed sensor utilizes inexpensive software-defined radio (SDR) measurements, offering a cost-effective solution. Unlike previous MM sensors employing SRR configuration, our proposed MM-motivated sensor is integrated with a microstrip feedline and an additional vertical bar, enhancing its sensing capability. To enable accurate measurements, a simple calibration procedure based on baseline normalization is implemented, allowing for amplitude-only transmission measurements (|S-21|) using the SDR. A special sample holder was designed to increase the repeatability of measurements. We separately employ two postprocessing techniques, namely, the rolling average (RA) approach and the Savitzky-Golay (SG) filter, to effectively eliminate ripples in the measured |S-21| data obtained from the SDR. For validation and evaluation of the proposed sensor and postprocessing techniques, measurements of flower honey samples with water adulteration levels (delta ) up to 10% (mass-to-mass basis) were also performed using a vector network analyzer (VNA). The resonance frequency of |S21| is utilized as the basis for analysis. We establish a metric function (linear function) that correlates the shift in resonance frequency with delta. It is observed that this function fits to measured resonance frequency values with an R(2 )value greater than 0.96 for both postprocessing techniques with or without the sample holder. By inverting this function, we can predict delta with considerable accuracy for a given resonance frequency by using another linear function. It is observed that percentage variations between predicted and measured delta values are between 1.54% and 6.46% for testing samples with delta = 5% and delta = 7%.
AtıfScopus5WoS2OpenAlex5
İncele - MakaleAçık Erişim2022Scopus SJRQ3IoT-TDMA: A performance evaluation of TDMA scheme for wireless sensor networks with Internet of Things
Kosunalp, Selahattin; Kaya, Yunus
This article focuses on the design and implementation of an improved version of TDMA scheme for wireless sensor networks (WSNs) exploiting the Internet of Things (IoT) phenomena. The main motivation behind this work is to create an environment for WSNs to benefit from IoT opportunities. An extensive review of the state-of-the-art medium access control (MAC) approaches proposed for IoT is carried out underlying their basic principles and features. An adaptation of TDMA strategy, called IoT-TDMA, is proposed to enhance the channel performances particularly throughput and latency. To test the performance of IoT-TDMA practically, a low-cost node hardware with the capability of Internet connection is essentially designed. IoT-TDMA has been implemented on real-world highly scalable single-hop and multi-hop topologies. Performance results indicate significant improvements in terms of channel throughput and end-to-end delay in comparison to a recently proposed efficient MAC scheme.
AtıfScopus17OpenAlex18İncele - MakaleAçık Erişim2019Efficient Deployment of Energy Antenna for Sensor Nodes with RF Charging
Tabakcıoğlu, Mehmet Barış; Zorlu, Ahmet; Kosunalp, Selahattin
A sensor node has processor, antenna, sensor and energy units. A large number of sensor nodes generateswireless sensor network (WSN). The main problem of WSN is limited-energy. A great number of MACprotocols are introduced to compensate the energy problem. In order to supply energy to sensor nodes, anexternal solar panel, wind turbine and energy harvester are added to the architecture of the nodes. Moreover,wireless energy transfer is used to meet the energy problem of sensor node. Position, height and operatingfrequency of energy antenna is so important to charge the sensor nodes efficiently. In this study, ray theoreticalmodels are used to calculate the electric field and generate the coverage map. As the energy antenna is deployedto optimum place, charging will complete in a short time.
- BildiriYalnız künye2017Harvesting Solar Energy for Limited-Energy Problem in Wireless Sensor Networks
Kosunalp, Selahattin; Cihan, Ahmet
The major problem in wireless sensor networks (WSNs) is the limited-energy source, typically small batteries, employed by sensors. In order to prolong the lifetime of the WSNs, a lot of approaches have taken the limited-energy problem as a primarily design criterion. However, inevitable energy depletion will eventually disturb the operation of the WSNs. Recent studies have shown that renewable energy sources would potentially provide an infinite energy source for powering WSNs. Solar energy is the most effective energy source for WSNs as it has the largest power intensity. Therefore, each sensor which requires a small amount of energy for efficient operation can harvest sufficient energy from solar. In this study, a platform is designed in order to allow sensors to exploit solar energy. The performance of the sensors in terms of the lifetime is practically studied. The results demonstrate that sensors can also survive when there is no energy available through storing energy in a super-capacitor. IRIS nodes are used in experiments as they are very popular in WSNs domain.
- MakaleAçık Erişim2017Scopus SJRQ1An energy prediction algorithm for wind-powered wireless sensor networks with energy harvesting
Kosunalp, Selahattin
Energy harvesting (EH) from environmental energy sources has the potential to ensure unlimited, uncontrollable and unreliable energy for wireless sensor networks (WSNs), bringing a need to predict future energy availability for the effective utilization of the harvested energy. The majority of previous prediction approaches have exploited the diurnal cycle dividing the whole day into equal-length time slots in which predictions were carried out in each slot independently. This is not, however, efficient for wind energy as it exhibits non-controllable behaviour in that the amount of energy to be harvested varies over time. This paper proposes a novel approach to predict the wind energy for EH-WSNs depending on the energy generation profile of latest condition. The distinctive feature of the proposed approach is to consider the recent conditions in current-day, instead of past-day's energy generation profiles. The performance of the proposed algorithm is evaluated using real measurements in comparison with state-of-art approaches. Results show that the proposed strategy significantly outperforms the two popular energy predictors, EWMA and Pro-Energy.
AtıfScopus48WoS36OpenAlex51İncele - BildiriÖn baskısı açık2016Medium Access Control Protocols for Wireless Sensor Networks with Ambient Energy
Kosunalp, Selahattin; Tabakcioglu, Mehmet Baris
Wireless sensor networks (WSNs) have recently been a popular research area with a broad range of applications. One of the most significant constraints of WSNs is energy limitation of sensor nodes. Therefore, energy-efficiency has been considered as primarily design criterion in many medium access control (MAC) protocols developed. In order to solve the issue of limited-energy sources, various recent protocols have focused on energy harvesting from surrounding environment, such as solar, wind and vibration energy, resulting in providing unlimited energy source. Ambient energy exhibits a characteristic of unlimited energy source but not available always due to environmental changes. The focus is now being placed on effective utilization of the time-varying ambient energy. This study aims to provide a review of recently proposed MAC protocols for energy-harvesting WSNs describing their operating principles and underlying features.
- MakaleAçık Erişim2016Scopus SJRQ1Use of Q-learning approaches for practical medium access control in wireless sensor networks
Kosunalp, Selahattin; Chu, Yi; Mitchell, Paul D.; Grace, David; Clarke, Tim
This paper studies the potential of a novel approach to ensure more efficient and intelligent assignment of capacity through medium access control (MAC) in practical wireless sensor networks. Q-Learning is employed as an intelligent transmission strategy. We review the existing MAC protocols in the context of Q-learning. A recently-proposed, ALOHA and Q-Learning based MAC scheme, ALOHA-Q, is considered which improves the channel performance significantly with a key benefit of simplicity. Practical implementation issues of ALOHA-Q are studied. We demonstrate the performance of the ALOHA-Q through extensive simulations and evaluations in various testbeds. A new exploration/exploitation method is proposed to strengthen the merits of the ALOHA-Q against dynamic the channel and environment conditions.
AtıfScopus41WoS29OpenAlex37İncele - MakaleAçık Erişim2016Scopus SJRQ2Practical implementation and stability analysis of ALOHA-Q for wireless sensor networks
Kosunalp, Selahattin; Mitchell, Paul Daniel; Grace, David; Clarke, Tim
This paper presents the description, practical implementation, and stability analysis of a recently proposed, energy-efficient, medium access control protocol for wireless sensor networks, ALOHA-Q, which employs a reinforcement-learning framework as an intelligent transmission strategy. The channel performance is evaluated through a simulation and experiments conducted using a real-world test-bed. The stability of the system against possible changes in the environment and changing channel conditions is studied with a discussion on the resilience level of the system. A Markov model is derived to represent the system behavior and estimate the time in which the system loses its operation. A novel scheme is also proposed to protect the lifetime of the system when the environment and channel conditions do not sufficiently maintain the system operation.
AtıfScopus7WoS3OpenAlex8İncele - MakaleAçık Erişim2016Scopus SJRQ1A New Energy Prediction Algorithm for Energy-Harvesting Wireless Sensor Networks With Q-Learning
Kosunalp, Selahattin
Traditional wireless sensor networks (WSNs) face the problem of a limited-energy source, typically batteries, resulting in the need for careful and effective utilization of the energy source. However, inevitable energy depletion will eventually disturb the operation of a WSN. Energy harvesting (EH) technology is acquiring particular interest, because it has the potential to provide a continuous energy supply in battery-powered WSNs. Solar energy is the most effective environmental energy for EH-WSNs because of its high energy intensity, which comes from a non-controllable source. Therefore, the prediction of future energy availability is a critical issue, as the amount of the harvestable energy may vary over time. In this paper, a novel solar energy prediction algorithm with Q-learning, called Q-learning-based solar energy prediction (QL-SEP), is proposed. Q-learning is an effective way of predicting future actions based on past observations. The distinctive feature of QL-SEP is that not only past days' observations but also the current weather conditions are considered for prediction. The performance of QL-SEP is simulated in this paper using real-world measurements obtained from a solar panel in comparison with the state-of-art approaches.
AtıfScopus128WoS96OpenAlex135İncele - MakaleAçık Erişim2015Scopus SJRQ2MAC protocols for energy harvesting wireless sensor networks: Survey
Kosunalp, Selahattin
Energy harvesting (EH) technology in the field of wireless sensor networks (WSNs) is gaining increasing popularity through removing the burden of having to replace/recharge depleted energy sources by energy harvester devices. EH provides an alternative source of energy from the surrounding environment; therefore, by exploiting the EH process, WSNs can achieve a perpetual lifetime. In view of this, emphasis is being placed on the design of new medium access control (MAC) protocols that aim to maximize the lifetime of WSNs by using the maximum possible amount of harvested energy instead of saving any residual energy, given that the rate of energy harvested is greater than that which is consumed. Various MAC protocols with the objective of exploiting ambient energy have been proposed for energy-harvesting WSNs (EH-WSNs). In this paper, first, the fundamental properties of EH-WSN architecture are outlined. Then, several MAC protocols proposed for EH-WSNs are presented, describing their operating principles and underlying features. To give an insight into future research directions, open research issues (key ideas) with respect to design trade-offs are discussed at the end of this paper.
AtıfScopus56WoS45OpenAlex57İncele
