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Article Citation - WoS: 5Citation - Scopus: 6Systematic Investigation of the Effects of Unidirectional Links on the Lifetime of Wireless Sensor Networks(Elsevier, 2013) Ozyer, Sibel T.; Tavli, Bulent; Dursun, Kayhan; Koyuncu, MuratLink unidirectionality is a commonly encountered phenomenon in wireless sensor networks (WSNs), which is a natural result of various properties of wireless transceivers as well as the environment. Transmission power heterogeneity and random irregularities are important factors that create unidirectional links. Majority of the internode data transfer mechanisms are designed to work on bidirectional links (i.e., due to the lack of a direct reverse path, handshaking cannot be performed between a transmitter and receiver) which render the use of unidirectional links infeasible. Yet, there are some data transfer mechanisms designed specifically to operate on unidirectional links which employ distributed handshaking mechanisms (i.e., instead of using a direct reverse path, a multi-hop reverse path is used for the handshake). In this study, we investigate the impact of both transmission power heterogeneity and random irregularities on the lifetime of WSNs through a novel linear programming (LP) framework both for networks that utilize only bidirectional links and for those that can use bidirectional links as well as unidirectional links. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 62Citation - Scopus: 78Hybrid Microgrid for Microfinance Institutions in Rural Areas - a Field Demonstration in West Africa(Elsevier, 2019) Ayodele, Esan; Misra, Sanjay; Damasevicius, Robertas; Maskeliunas, RytisWe present a hybrid energy microgrid optimization model for a microbank in a remote rural residential area. The model is based on the use of renewable (wind turbines & solar photovoltaic (PV)) and conventional (gasoline generators) energy sources and battery storage systems. We conducted a detailed assessment of a typical microbank's load, residential loads and energy resources in a village called Ajasse-Ipo in Kwara State, Nigeria. We performed the modeling of a hybrid microgrid system, followed by an economic analysis and sensitivity analysis to optimize the hybrid system design. We performed simulations based on the energy resources available (solar PV, wind, gasoline generator & battery energy storage system) to satisfy the energy demands of the microbank, while the excess energy was supplied to meet the demand of the community loads, i.e. water pumping machine and rural home lighting. The results obtained showed that the hybrid system comprising the solar PV/battery/diesel was most techno-economically viable with a Net Present Cost (NPC) and Cost of Energy (COE) of $468,914 and 0.667$/kWh, respectively. Comparing these results with those obtained using analytical methods, the solar PV, battery and converter sizes obtained were slightly higher than the optimal system configurations as produced by HOMER. The proposed hybrid energy system also allowed to achieve almost 50% reductions in CO2, CO, unburned hydrocarbons, particulate matter, SO2 & NO2. The system can be applicable for other rural regions in the developing countries with similar environmental conditions.Article Citation - WoS: 19Citation - Scopus: 20A Framework for Energy Reduction in Manufacturing Process Chains (e-Mpc) and a Case Study From the Turkish Household Appliance Industry(Elsevier Sci Ltd, 2016) Uluer, Muhtar Ural; Unver, Hakki Ozgur; Gok, Gozde; Fescioglu-Unver, Nilgun; Kilic, Sadik EnginEnergy is a major input in the manufacturing sector. Its security and efficiency are of supreme importance to a nation's industrial activities. Energy consumption also has serious environmental impacts in terms of Greenhouse Gas (GHG) emissions. In order to use energy more efficiently, simply designing parts and planning manufacturing processes with an energy-aware mindset is insufficient; it is also necessary to model and assess the energy efficiency of a process chain from a holistic point of view. In this work, we propose an integrated energy reduction framework and the internal methods to implement it. Our framework builds on three pillars. Creating an energy profile of a process chain is the first step in characterizing a manufacturing system in terms of energy demand. Energy-aware part designs and process plans are based on ISO/STEP 10303 AP224 standards in order to estimate the embodied energy of a mechanical part. Finally, using discrete event simulation methods, the energy consumption of a process chain is assessed and reduction scenarios are generated based on design or operational alternatives. A data collection and analytics system visualizing measures and key performance indicators (KPIs) also must be implemented in order to measure real consumption values and track improvement results over time. The energy reduction in manufacturing process chains (E-MPC) framework is unique in that it provides a structured method which enables the embodied energy of a part to be estimated during early design stages and further enables the evaluation of design impacts on process chains, thereby recognizing the dynamic nature of systems. A pilot case study of the framework was implemented at the largest household appliance manufacturer in Turkey, Arcelik A.S. In order to evaluate its usefulness and validity, we performed a detailed implementation on a fully automated crankshaft manufacturing line in Arcelilc's refrigerator compressor plant. The results reveal that design improvements estimated gains would reach 2%, whereas operational improvements yield up to 10% energy savings per produced part. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 1Zero Consumption Monotype Education Buildings(Gazi Univ, 2018) Bal Kocyigit, FilizTurkey has mainly seven geographic zones but four climatic zones. Major influence on energy usage and educational buildings which perform well in energy terms will reap significant environmental and economic benefits for years to come. The lack of electric, heating-cooling and lighting comfort in the structure reduce the quality of education. Many village schools cannot provide training in enough conditions. Municipalities are preparing "Type School Project" for government schools, without thinking different zones conditions, directions and heights. At this stage, there arises importance of the Architectural Design Process for typical energy efficient design which can easily adapt to the location. The material must not only be transmits about 70-90% of solar radiation, but also its insulation quality. Additionally architectural form of building must be affected to take all solar energy, wind and water. In this study, architectural design method has been used for energy gain from transparent insulated trombe wall. And have been calculated in accordance with their manners in the middle, south, noth, east and west regions of Anatolia which are located in different degree-days regions on the basis of TS 825.
