4653 research outputs found
Sort by
Extended exergy analysis of a solar driven water production plant via reverse osmosis
Get PDFWater scarcity and contamination of available water are becoming one of the most complex problems worldwide and they compromise economic development, global sustainability, and human supply, among others. Water is required in almost all human activities and also for planet equilibrium in terms of biodiversity. In this research a new home scaled water desalination plant, using a reverse osmosis technology and driven with solar energy is analyzed via extended exergy analysis, which is one of the most accurate methods for evaluating both energy performance and sustainability. The proposed system, that is presented and analyzed, consists of a solar concentrator having 1000 concentrating rate, a Photon Enhanced Thermionic Emitter, a Dye-Sensitized Solar Cell for the electricity generation and a Reverse Osmosis Desalination Plant (RODP) for water purification using the produced electricity. This system allows water desalination in small scale plants requiring low density energy sources and can produce sustainable water for multiples uses, such as domestic use or agricultural, among others. The most important results are labor and capital exergy equivalents, 42.68 MJ/workhour and 12.09 MJ/Euro, respectively, and an exergy destruction of 389.700 GJ for all the system annually. The proposed technology can be extended and used in different locations and the Extended Exergy Analysis can be used as a powerful tool for both design and optimization
The effect of Covid-19 threat on warm and competent political leader preferences: Differences between preferences of left-and right-oriented people
Get PDFDual-Band Omnidirectional and Circularly Polarized Slotted Waveguide Array Antenna for Satellite Telemetry and Telecommand
Get PDFIn this letter, the design and 3-D-printed manufacturing of an omnidirectional and circularly polarized dual-band antenna for telemetry/telecommand (TMTC) applications in satellite communication on space segment are described. The antenna consists of slotted arrays on the circular waveguide with radially outward metallic disks and choke structures on these disks to improve the omnidirectionality and circular polarization performances. As the main novelty of the antenna design, the structure is fed with only one rectangular waveguide; therefore, the proposed antenna can be considered as a transceiver antenna. The design and simulations of the antenna and measurement results for 3-D-printed manufacturing are given at Ku-band. A 10 dB return loss bandwidth is found to be 500 MHz both for telemetry and telecommand bands having center frequencies of 12 and 14 GHz, respectively. Besides, the maximum axial ratio and minimum gain within 65° beamwidth are obtained as 3 dB and-5 dBi, respectively, which are sufficient for the omnidirectional and circularly polarized antenna providing TMTC communication in satellite systems
Çevresel sürdürülebilirlik stratejileri: Türkiye'deki on büyükşehir belediyesinin karşılaştırmalı bir incelemesi
Get PDFHospital layout design renovation as a Quadratic Assignment Problem with geodesic distances
Get PDFHospital facilities are known as functionally complex buildings. There are usually configurational problems that lead to inefficient transportation processes for patients, medical staff, and/or logistics of materials. The Quadratic Assignment Problem (QAP) is a well-known problem in the field of Operations Research from the category of the facility's location/allocation problems. However, it has rarely been utilized in architectural design practice. This paper presents a formulation of such logistics issues as a QAP for space planning processes aimed at renovation of existing hospitals, a heuristic QAP solver developed in a CAD environment, and its implementation as a computational design tool designed to be used by architects. The tool is implemented in C# for Grasshopper (GH), a plugin of Rhinoceros CAD software. This tool minimizes the internal transportation processes between interrelated facilities where each facility is assigned to a location in an existing building. In our model, the problem of assignment is relaxed in that a single facility may be allowed to be allocated within multiple voxel locations, thus alleviating the complexity of the unequal area assignment problem. The QAP formulation takes into account both the flows between facilities and distances between locations. The distance matrix is obtained from the spatial network of the building by using graph traversal techniques. The developed tool also calculates spatial geodesic distances (walkable, easiest, and/or shortest paths for pedestrians) inside the building. The QAP is solved by a heuristic optimization algorithm, called Iterated Local Search. Using one exemplary real test case, we demonstrate the potential of this method in the context of hospital layout design/re-design tasks in 3D. Finally, we discuss the results and possible further developments concerning a generic computational space planning framework
Building supply chain resilience in the era of COVID-19: An AHP-DEMATEL approach
Get PDFCOVID-19 pandemic is the worst humanitarian crisis that economies across the globe have witnessed. Forced lockdowns, social distancing, and restricted mobility have contributed to large scale disruptions in the supply chain network. The purpose of the paper is to identify critical factors affecting global supply chain and evaluate strategies for risk reduction in the supply chain network by making it resilient. Our study incorporates multi-criteria decision approach using Analytic Hierarchy Process (AHP) and Decision-Making Trial and Evaluation Laboratory (DEMATEL) to analyze factors that affected the supply chain networks with the onset of COVID-19. The AHP method enabled to hierarchically rank the factors based on the relative weightage while DEMATEL ascertained the inter-relationships among the factors and classified them into cause and effect groups. The findings of our study identified the cost–optimization as the most significant factor and the human resource management as the least important factor in reducing vulnerabilities of the supply chain network. Our analysis from DEMATEL approach indicate that government support is a significant causal factor which can effectively eliminate the issues plaguing supply chains during this pandemic. The results from our study aim to help policymakers in developing a risk resilient framework that can enhance performance and operational capability of the supply chain, thereby ensuring sustainability and socio-economic well-being of all the stakeholders involved in the entire network
Public attitudes towards climate change: A cross-country analysis
No full textAddressing climate change requires international effort from both governments and the public. Climate change concern is a crucial variable influencing public support for measures to address climate change. Combining country-level data with data from the PProject Evaluation Commission of Yasar University [BAP053]International Relations; Political ScienceInternational Relations; Government & La
The Impacts Of Covid-19 Pandemic On Turkishkish Businesses: Problems, Transformations, Opportunities
No full textBu çalışmanın amacı, Türkiye’de farklı endüstrilerde faaliyet gösteren işletmelerin Covid-19 salgınından nasıl etkilendiklerini, oluşan yeni zorlu koşullara verdikleri yanıtları ve önümüzdeki süreç için öngörülerini analiz etmektir. Bunun için iki farklıThe aim of this study is to understand how Turkishkish businesses operating in diverse
industries have been affected from Covid-19 outbreak, their responses to the present conditions,
and their predictions for the upcoming period. For this purpose, 84
Inferring political and religious attitudes from composite faces perceived to be related to the dark triad personality traits
Get PDFWe used composite face images perceived to have different levels of Dark Triad personality traits (narcissism, psychopathy, and Machiavellianism) and asked participants to predict these target individuals' religious and political identities. In Study 1 (N = 550), Turkish participants rated faces with higher levels of perceived Dark Triad traits as less likely to be religious, to believe in God, and more likely to be left-winger, and to vote for a leftleaning party in all categories except for male narcissism. In a pre-registered follow-up study (N = 1001), we recruited a nationally representative US sample and replicated the same results with minor differences regarding male and female narcissism, and voting preferences. Participants' own political and ideological identities and their stereotypical evaluation of the target groups were mostly ineffective in explaining their predictions. The results suggest that people can perceive faces with higher levels of Dark Triad traits as less religious and less conservative