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CONTENTS
Volume 7, Number 1, March 2020
 

Abstract
Energy consumption of air-conditioning and refrigeration systems is responsible for about 25 to 30% of the energy demand especially in hot seasons. This equipment is mostly electricity dependent and their use in principle affects negatively the environment. Enhancing the energy efficiency of the existing equipment is important as one of the measures to reduce environment impacts. This paper reports the results of an experimental study to evaluate the impacts of the use electronic expansion valve and variable velocity compressor on the performance of vapor compression refrigeration system. The experimental rig is composed of two independent circuits one for the vapor compression system and the other is the secondary fluid system. The vapor compression system is composed of a forced air condenser unit, evaporator, hermetic compressor and expansion elements, while the secondary system has a pump for circulating the secondary fluid, and an air conditioning heat exchanger. The manufacturer\'s data was used to determine the optimal points of operation of the system and consequently tests were done to evaluate the influence of variation of the compressor velocity and the opening of the expansion device on the performance of the refrigeration system. A fuzzy logic model was developed to control the rotational velocity of the compressor and the thermal load. Fuzzy control model was made in LabVIEW software with the objective of improving the system performance, stability and energy saving. The results showed that the use of fuzzy logic as a form of control strategy resulted in a better energy efficiency.

Key Words
variable velocity compressor; electronic expansion valve; fuzzy control; coefficient of performance; efficiency

Address
Taynara G.S. Lago, Kamal A.R. Ismail, Cláudia R.E.S. Nóbrega and Luiz F.M. Moura: Department of Energy, Faculty of Mechanical Engineering, State University of Campinas, UNICAMP, Mendeleyev Street, 200, 13083-860, Campinas, Brazil

Abstract
Energy storage devices have received a keen interest throughout the world due to high power consumption. A large number of research activities are being conducted on electrochemical double layer capacitors (EDLCs) because of their high power density and higher energy density. In the present study, an EDLC was fabricated using natural graphite based electrodes and ionic liquid (IL) based gel polymer electrolyte (GPE). The IL based GPE was prepared using the IL, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (1E3MITF) with the polymer poly(vinyl chloride) (PVC) and the salt magnesium trifluoromethanesulfonate (Mg(CF3SO3)2 - MgTF). GPE was characterized by electrochemical impedance spectroscopy (EIS), DC polarization test, linear sweep voltammetry (LSV) test and cyclic voltammetry (CV) test. The maximum room temperature conductivity of the sample was 1.64 x 10-4 Scm-1. The electrolyte was purely an ionic conductor and the anionic contribution was prominent. Fabricated EDLC was characterized by EIS, CV and galvanostatic charge discharge (GCD) tests. CV test of the EDLC exhibits a single electrode specific capacitance of 1.44 Fg-1 initially and GCD test gives 0.83 Fg-1 as initial single electrode specific discharge capacitance. Moreover, a good stability was observed for prolonged cycling and the device can be used for applications with further modifications.

Key Words
ionic liquid; electrochemical double layer capacitor; natural graphite; gel polymer electrolyte; 1-ethyl-3-methylimidazolium trifluoromethanesulfonate

Address
Kumudu S. Perera, K.W. Prasadini and Kamal P. Vidanapathirana: Polymer Electronics Research Group. Department of Electronics,
Wayamba University of Sri Lanka, Kuliyapitiya, Sri Lanka

Abstract
The paper proposes a hybrid approach of artificial bee colony (ABC) and grey wolf optimizer (GWO) algorithm for multi-objective and multidimensional engine optimization of a converted plug-in hybrid electric vehicle. The proposed strategy is used to optimize all emissions along with brake specific fuel consumption (FC) for converted parallel operated diesel plug-in hybrid electric vehicle (PHEV). All emissions particulate matter (PM), nitrogen oxide (NOx), carbon monoxide (CO) and hydrocarbon (HC) are considered as optimization parameters with weighted factors. 70 hp engine data of NOx, PM, HC, CO and FC obtained from Oak Ridge National Laboratory is used for the study. The algorithm is initialized with feasible solutions followed by the employee bee phase of artificial bee colony algorithm to provide exploitation. Onlooker and scout bee phase is replaced by GWO algorithm to provide exploration. MATLAB program is used for simulation. Hybrid ABC-GWO algorithm developed is tested extensively for various values of speeds and torque. The optimization performance and its environmental impact are discussed in detail. The optimization results obtained are verified by real data engine maps. It is also compared with modified ABC and GWO algorithm for checking the effectiveness of proposed algorithm. Hybrid ABC-GWO offers combine benefits of ABC and GWO by reducing computational load and complexity with less computation time providing a balance of exploitation and exploration and passes repeatability towards use for real-time optimization.

Key Words
ABC; emissions; GWO; MATLAB; optimization; PHEV

Address
Pritam K. Gujarathi and Varsha A. Shah: Department of Electrical Engineering, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat-395007, India

Makarand M. Lokhande: Department of Electrical Engineering, Visvesvaraya National Institute of Technology,
Nagpur, Maharashtra-440010, India





Abstract
Before the industrial revolution architecture has been shaped by the natural and cultural inputs. Local constraints become more effective determinants of architecture in the rural contexts because by being disengaged from the webs of transportation and communication, rural settlements have achieved sustainability in difficult conditions. The examples of rural settlement and architecture have provided sustainability through integration with natural inputs within the geographical context because they have reached the goals of ecological design within the local constraints. Although this feature of the rural cultural landscapes has been emphasized frequently, tangible standards could not be developed in order to interpret their ecological design principles from the perspectives of the contemporary building sector and planning. However, the historical experience indicates that the sustenance of ecological performance can be possible as a result of integrated planning at the overall scale of the settlement. Therefore, the existing standards are not qualified for interpreting the rural contexts. This study develops a method for analysing, interpreting and evaluating traditional rural settlements and certifying new implementations in the rural environments in the light of the given literature review, discussion and methodological proposal.

Key Words
ecology; rural settlements; ecological certification

Address
Kemal Reha Kavas and Hacer Mutlu Danaci: Department of Architecture, Faculty of Architecture, Akdeniz University, 07058, Antalya, Turkey

Isa Cal: Department of Architecture, Faculty of Architecture, Yildiz Technical University, Istanbul, 34349, Turkey

Abstract
Given the recent surge of interest towards utilization of renewable distributed energy resources (DER), in particular in remote areas, this paper aims at designing an optimal hybrid system in order to supply loads of a village located in Esfarayen, North Khorasan, Iran. This paper illustrates the optimal design procedure of a standalone hybrid system which consists of Wind Turbine Generator (WTG), Photo Voltaic (PV), Diesel-generator, and Battery denoting as the Energy Storage System (ESS). The WTGs and PVs are considered as the main producers since the site\'s ambient conditions are suitable for such producers. Moreover, batteries are employed to smooth out the variable outputs of these renewable resources. To this end, whenever the available power generation is higher than the demanded amount, the excess energy will be stored in ESS to be injected into the system in the time of insufficient power generation. Since the stand-alone system is assumed to have no connection to the upstream network, it must be able to supply the loads without any load curtailment. In this regard, a Diesel-Generator can also be integrated to achieve zero loss of load. The optimal hybrid system design problem is a discrete optimization problem that is solved, here, by means of a recently-introduced meta-heuristic optimization algorithm known as Lightning Attachment Procedure Optimization (LAPO). The results are compared to those of some other methods and discussed in detail. The results also show that the total cost of the designed stand-alone system in 25 years is around 92 M

Key Words
hybrid system, standalone, meta-heuristic optimization algorithm; renewable energy resources

Address
Navid Shiva and Abolfazl Rahiminejad: Department of Electrical and Computer Science, Esfarayen University of Technology, Esfarayen, Iran

Amin Foroughi Nematollahi and Behrooz Vahidi: Department of Electrical Engineering, Amirkabir University of Technology, Tehran, 1591634311, Iran



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