Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(47)
- Pat, Suat(29)
- Özen, Soner(29)
- Şenay, Volkan(24)
- Korkmaz, Şadan(23)
- Esmer, Yusuf(21)
- Şahin, Engin(21)
- Korkmaz, Özge(20)
- Cuce, Erdem(19)
- Öner, Erdal(18)
- Öztürk, Mesut(18)
- Artar, Musa(17)
- Yilmaz, Mustafa Tahsin(17)
- İspirli, Hümeyra(16)
- Ecem Bayram, Nesrin(15)
- Kaya, Yunus(15)
- Cinar, Mehmet(13)
- Cuce, Pinar Mert(12)
- Kamiloğlu, Aybike(12)
- Kutlu, Naciye(12)
- Mercan, Emin(12)
- Birinci, Ahmet(11)
- Bulut, Mehmet(11)
- Yaylacı, Murat(11)
- Bayram, Ozkan(10)
- Can, Zehra(10)
- Doğan, Zeki(10)
- Kahya, Cem(10)
- Karaali, Rabi(10)
- Pabuçcu, Hakan(10)
- Tosun, Figen Çam(10)
- Özdemir, Akın(10)
- Ayazoglu, Rabil(9)
- Battal, Fetullah(9)
- Bayram, Nesrin Ecem(9)
- Büte, Mustafa(9)
- Ertugrul, Mehmet(9)
- Kadakal, Mahir(9)
- Kaplan, Abdullah(9)
- Sarikaya, İsmail(9)
Yayınlar
- MakaleYalnız künye2018Scopus SJRQ2Normal neutrosophic multiple attribute decision making based on generalized prioritized aggregation operators
Şahin, Rıdvan
Normal neutrosophic set, which allows a combination of the normal fuzzy number and the neutrosophic number, is a powerful tool for handling the incompleteness, indeterminacy and inconsistency of evaluation information. Based on the opinion of prioritized aggregation operators developed to describe the prioritization relationships among several attributes, this paper investigates some prioritized aggregation operators for aggregating the normal neutrosophic information, such as normal neutrosophic prioritized weighted averaging operator and normal neutrosophic prioritized weighted geometric operator, and then extends these operators to the generalized prioritized weighted aggregation operators, including normal neutrosophic generalized prioritized weighted averaging operator and normal neutrosophic generalized prioritized weighted geometric operator, respectively. They can take into account the prioritization facts in the aggregated information. Moreover, some of their desirable properties are investigated in detail. A multiple attribute decision-making method is developed for solving a kind of problems in which the decision attributes have different priority level commonly and they take the form of normal neutrosophic numbers. Finally, an illustrative example based on the prioritization relationship over the evaluation data is given to depict the effectiveness and feasibility of the developed decision-making method, which are then compared to the existing approaches.
AtıfScopus14WoS18OpenAlex20
İncele - Kitap BölümüYalnız künye2018Scopus SJRQ3Contribution of the cogeneration systems to environment and sustainability
Kemal, Çomakli; Uğur, Çakir; Ayşegül, Çokgez Kuş; Erol, Şahin; Aloui, F; Dincer, I
The kind of energy that buildings need changes, like heating energy, cooling energy, electrical energy, and thermal energy for hot top water. Usually, the processes or systems that produce thermal energy emit pollutants while they produce heat because of the fossil fuels they use. A lower consumption of thermal energy will contribute not only to a reduction in the running costs but also in the reduction of pollutant emissions that contribute to the greenhouse effect and a lesser dependence of the hospital on the external power supply. Cogeneration or CHP (combined heat and power) is the system that produces power and usable heat simultaneously. Combined production of mechanical or electrical and thermal energy using a simple energy source, such as oil, coal, natural or liquefied gas, biomass, or the sun, affords remarkable energy savings and frequently makes it possible to operate with greater efficiency when compared to a system producing heat and power separately. Because of the life standard of humanity in new age, energy sources must be continually improved and updated. For this reason, the installation of a system for the simultaneous generation of electrical, heating, and cooling energy would be one of the best solutions if we want to have qualified energy and reduce investment and operating costs and meet ecological requirements. This study aims to bring out the contributions of cogeneration systems to the environment and sustainability by saving the energy and reducing the emissions.
AtıfOpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ2Changes of surface properties of calcite particles with calcium stearate using conventional experimental design and properties of coated calcite
Ucurum, Metin; Bayram, Ozkan; Toraman, O. Yusuf; Kilic, Habibe; Yalcin, Seyma
Calcite is utilized as a filler mineral in the industries such as plastics, rubber, and paint, to gain products with a variety of features. In order to use a calcite ore as a filler, some specific physical and physico-chemical properties are required such as ultra-fine sizes and conversion of hydrophilic to hydrophobic structure. In the present study, for these purposes, surfaces of the ultra-fine calcite powder (d50=2.94 μm) were coated by a mechano-chemical process with calcium stearate [Ca(C17H35COO)2] in a stirred ball mill. The influence of operating parameters such as calcite filling-ratio, ball-filling ratio, operation speed, grinding time and chemical dosage on the active ratio (%) was systematically examined. Then, the properties of modified calcite product were measured and evaluated by contact angle, TGA, DTA, FTIR, and SEM. The results showed that the mechano-chemical technology is very effective for modifying the surface of micronized calcite products using calcium stearate chemical.
AtıfScopus20WoS18İncele - MakaleYalnız künye2018Scopus SJRQ3Width, length, and height conceptions of students with learning disabilities
Güven, N. Dilşad; Argün, Ziya
Teaching responsive to the needs of students with learning disabilities (LD) can be provided through understanding students’ conceptions and their ways of learning. The current research, as a case study based on qualitative design, aimed to investigate the conceptions of students with learning disabilities with regard to the different representations of length (width, length, and height). The participants were 3 Turkish students at 4th, 5th and 6th grades recognised by the local Counselling and Research Centre (CRC) as having learning disabilities. The data were collected through semistructured and task-based interviews, and analysed via content analysis method. The findings suggest that width, length, and height conceptions of students with learning disabilities are influenced by their conceptions of length and visual-spatial abilities.
AtıfScopus9İncele - MakaleYalnız künye2018Scopus SJRQ1Thermodynamic and thermoeconomic analyses of an organic Rankine cycle adapted gas turbine cycle using S-CO2 ; [Organik Rankine çevrimi entegre edilmiş S-CO2 kullanılan bir gaz türbin çevriminin termodinamik ve termoekonomik analizi]
Tozlu, Alperen; Özahi, Emrah; Abuşoğlu, Ayşegül
In this study, a model of an organic Rankine cycle (ORC) adopted gas turbine cycle using supercritical CO2 (S-CO2) as working fluid is performed. Thermodynamic analyses of a system are carried out using Aspen Plus and EES programs. As a result of thermodynamic analyses, electricity production capacity, energy and exergy efficiencies of the proposed system are evaluated as 1530.88 kW, 23.30% and 59.60%, respectively. For the thermoeconomic analysis of the system, specific exergy costing method, SPECO, is applied as widely used one among the second law based methods. Unit exergetic cost of electricity production for 1 kWh is found to be 7.28 ¢ and the total cost of electricity production for 1530.88 kWh is found to be 114.43 $. Annual return from the system of ORC adopted gas turbine cycle using S-CO2which has the total investment cost of 3,033,300 $ is evaluated as 741,146 $ taking into account the difference between the cost of electricity production and the sale price of electricity. As a result of the thermoeconomic analysis, the payback period of the system is found to be 4.09 years. Purpose: To propose a model (an organic Rankine cycle (ORC) adopted gas turbine cycle using supercritical CO2: S-CO2) for an existing solid waste power plant in the frame of the heat recovery (Waste-to-energy). Theory and Methods: Thermodynamic and thermoeconomic analyses were utilized for the proposed model in order to evaluate the energy and exergy efficiencies. Results: The energy and exergy efficiencies of the system were calculated as 23.30 % and 61.60 % respectively. 1 kWh of electricity generated from GT-ORC system is produced to 7.28 ¢. The total electricity production cost of 1530.88 kW-hours was calculated as $ 111.43. Conclusion: The total cost of the developed GT-ORC system is $ 3,033,300. The difference between the cost of electricity generated from the GT-ORC system and the cost of the electricity sales is expected to be $ 741,146 annually for the proposed GT-ORC system. As a result of this profit, the payback period of the system was calculated as 4.09 years.
AtıfScopus8İncele - MakaleYalnız künye2018Scopus SJRQ1Vibration and stability analysis of functionally graded sandwich beams by a multi-layer finite element
Kahya, Volkan; Turan, Muhittin
This paper presents a finite element model based on the first-order shear deformation theory for free vibration and buckling analyses of functionally graded (FG) sandwich beams. The present element has 3 N + 7 degrees-of-freedom for an N-layer beam. Lagrange's equations are employed for derivation of the equations of motion. Two types of FG sandwich beams are considered: (a) Type A with FG faces and homogeneous ceramic core, and (b) Type B with homogeneous ceramic and metal faces and FG core. Natural frequencies and buckling loads are calculated numerically for different boundary conditions, power-law indices, and span-to-height ratios. Accuracy of the present element is demonstrated by comparisons with the results available, and discussions are made on the results given in graphs and tables for the sandwich beams considered.
AtıfScopus89WoS81OpenAlex81İncele - MakaleYalnız künye2018Scopus SJRQ43-D simulation of simultaneous heat and mass transfer of apple
Turkan, B.; Canbolat, A.S.; Etemoglu, A.B.
Drying is a complex process associated with the coupled mechanism of heat and mass transfer which plays an important role in almost all industrial sectors. For this reason, the intensive research on drying is carried on specially based on optimisation of energy and process control. The aim of this study is to present a numerical method for drying processes widely used in food industries to provide enhanced product quality and economically advantages at definite production conditions. The governing equations of drying process in a 3-D rectangular object (e.g. apple slices) are solved numerically to predict the temperature and moisture distributions inside the object. Then, statistical tests of agreement between results are performed by determining the coefficient of regression (R2), chi-square test (2) and standard error of estimate (SEE) values, and it is found that predicted results agree well with the results in literature. Finally, a parametric study is conducted to emphasize the role of parameters on food drying as an important contributor to energy consumption.
AtıfScopus2İncele - MakaleYalnız künye2018Scopus SJRQ2Infinitely many solutions for a class of stationary Schrödinger equations with non-standard growth
Ayazoglu (Mashiyev), R.; Alisoy, Gulizar
In this paper, we study the existence of infinitely many solutions for a class of stationary Schrödinger type equations in ℝN involving the p(x)-Laplacian. The non-linearity is superlinear but does not satisfy the Ambrosetti-Rabinowitz type condition. The main arguments are based on the geometry supplied by Fountain Theorem. We also establish a Bartsch type compact embedding theorem for variable exponent spaces.
AtıfScopus2WoS1OpenAlex2İncele - MakaleYalnız künye2018Scopus SJRQ1The effects on performance, combustion and emission characteristics of DICI engine fuelled with TiO2 nanoparticles addition in diesel/biodiesel/n-butanol blends
Örs, I.; Sarıkoç, S.; Atabani, A.E.; Ünalan, S.; Akansu, S.O.
In this study, waste cooking oil biodiesel was mixed with titanium dioxide (TiO2), a metal-based nano particle, and n-butanol (C4H9OH) along with euro diesel to examine their effects on diesel engines. Various ratio of fuel blends were prepared with TiO2 nano particles-diesel-biodiesel and n-butanol. The tests fuels were euro diesel (D100), biodiesel (B100), B20, B20 + TiO2, B20But10 and B20But10 + TiO2, respectively. Thermo-physical properties such as density, pour point, cloud point, cold filter clogging point, flash point and kinematic viscosity of all test fuels were determined followed by investigating engine performance parameters such as torque, power, fuel consumption and etc. Combustion analysis was also investigated. In addition, the effects on emissions such as CO, CO2, HC, NO and smoke opacity were also carried out. The addition of n-butanol to the fuel blends substantially affected density, kinematic viscosity and cold flow properties, while the addition of TiO2 has not much effect on these properties. For all tested fuels, the maximum brake engine torque and power were recorded at approximately 1400 rpm and 2800 rpm, respectively. The addition of TiO2 increased the brake engine torque and power 10.20% and 9.74% and decreased the brake specific fuel consumption 27.73% and 28.37%, respectively compared to blends without TiO2 additive. TiO2 additive increases the maximum cylinder pressure and heat release rate, as a result improved the engine performance and combustion. The addition of n-butanol in the fuel blend increased the maximum cylinder pressure and heat release rate values in comparison to euro diesel. The results of exhaust emission showed a decrease in CO, HC and smoke opacity emissions, whereas increased CO2 and NO emission, except the use of n-butanol reduced the values of NO emission, in comparison to euro diesel and without TiO2 additive. The results show that biodiesel produced from waste cooking oil, n-butanol and TiO2 additive can be used in diesel engines at certain proportion and that the additive materials improve the combustion characteristics, engine performance and exhaust gas emission.
AtıfScopus231WoS193OpenAlex246İncele - Kitap BölümüYalnız künye2018Relationship between entrepreneurship and organization of akhism
Esmer, Yusuf; Yükse, Muhammet
Foreign direct investment, as an important instrument of economic development for developing countries, provides employment, technology transfer and productivity improvement by eliminating the capital deficiency in these countries. In recent years, foreign direct investments have increased considerably in developing countries. This increase makes it necessary to investigate the determinants of foreign direct investment. This paper focuses particularly on globalization and institutional quality variables that determine foreign direct investment using panel data of 48 developing countries from 1996 to 2015. The results suggest that globalization and institutional quality have a positive effect on foreign direct investment.
AtıfScopus1İncele - MakaleYalnız künye2018Scopus SJRQ3Determination of in-vitro antioxidant, anti-urease, anti-hyaluronidase activities by phenolic rich bee products from different region of Turkey
Can, Zehra
In this study, enzyme inhibition of urease and hyaluronidase are clinically important functions were examined by different authenticity bee products. Different floral honey, pollen and propolis samples were analyzed in terms of total phenolic compounds (TPC), total flavonoid contents (TFC), ferric reducing antioxidant capacity (FRAP), cupric reducing antioxidant capacity (CUPRAC), and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activities as antioxidant determinants. For the determination of the phenolic composition of the products, RP-UV-HPLC was used. TPC of the honey, pollen and propolis samples were ranged from 17 to 95 and 770 to 989 mg of gallic acid (GAE)/100g, 135-258 mg of GAE/g, and TFC was 1 to 10 mgQE/100g, and 78 to 99 mgQE/100 g, and 9 to 10 mg of QE/g, respectively. Among the bee products, propolis samples were showed the highest phenolic componds, that contained different quantity of protocatequic acid, catechin, caffeic acid, p-coumaric acid, p-hydroxybenzoic acid, ferulic acid and rutin. The urease inhibition vales (IC50) were changed from 7.02 to 33.25 mg/mL, 5.00 to 8.78 and 0.16 to 1.98 mg/mL in the honey, pollen and propolis samples, respectively. The hyaluronidase inhibition values (IC50) were changed from 0.02 to 0.46 g/mL, 0.02 to 0.26 g/mL and 3.26 to 9.21 μg/mL in the honey, pollen and propolis samples, respectively. Honey, pollen and propolis have a significant inhibition on the enzymes, the inhibition may be due to secondary metabolites of phenolic compounds and the mechanism of the inhibition should be studied in detailed.
AtıfScopus8İncele - MakaleYalnız künye2018Scopus SJRQ2Influence of freeze-thaw on strength of clayey soil stabilized with lime and perlite
Yilmaz, Fatih; Fidan, Duygu
Stabilization of clayey soil has been studied from past to present by mixing different additives to the soil to increase its strength and durability. In recent years, there has been an increasing interest in stabilization of soils with natural pozzolans. Despite this, very few studies have investigated the impact of pozzolanic additives under freeze-thaw cycling. This paper presents the results of an experimental research study on the durability behavior of clayey soils treated with lime and perlite. For this purpose, soil was stabilized with 6% lime content by weight of dry soil (optimum lime ratio of the the soil), perlite was mixed with it in 0%, 5%, 10%, 20%, 25% and 30% proportions. Test specimens were compacted in the laboratory and cured for 7, 28 and 84 days, after which they were tested for unconfined compression tests. In addition to this, they were subjected to 12 closed system freeze-thaw cycles after curing for 28 days. The results show that the addition of perlite as a pozzolanic additive to lime stabilized soil improves the strength and durability. Unconfined compressive strength increases with increased perlite content. The findings indicate that using natural pozzolan which is cheaper than lime, has positive effect in strength and durability of soils and can result cost reduction of stabilization.
AtıfScopus27WoS25OpenAlex15İncele - MakaleYalnız künye2018Scopus SJRQ1Effect of ultrasound treatment on the properties of nano-emulsion films obtained from hazelnut meal protein and clove essential oil
Gul, Osman; Saricaoglu, Furkan Turker; Besir, Aysegul; Atalar, Ilyas; Yazici, Fehmi
Hazelnut meal protein (4% (w/v)) and clove essential oil (CEO) (3% (v/v)) were homogenized with ultrasound (US) at different times (2, 4 and 6 min) and amplitudes (50, 75 and 100%) to obtain nano-emulsion films. Film forming nano-emulsions (FFNs) were analyzed for average particle size (Dz) and zeta potential, and edible film characterization were evaluated depending on US treatment, as well as antibacterial and antioxidant activities. Dz values and zeta potential of FFNs decreased with increasing acoustic energy delivered to nano-emulsion system. Thickness and water solubility of films significantly decreased with increasing US treatment. Films became more transparent depending on US treatment probably due to particle size reduction. Tensile strength (TS) of films significantly increased with US treatment, while elongation at break (EAB) slightly increased. Microstructure of films became more homogeneous after US treatment and caused to lower water vapor permeability. Enrichment with CEO has given the films antibacterial activity against L. monocytogenes, B. subtilis, S. aureus, P. aeruginosa and E. coli, and antioxidant activity, and US application has improved these activities. US technology can be used to improve mechanical, barrier and antimicrobial properties of hazelnut meal protein based edible films enriched with CEO.
AtıfScopus158WoS141OpenAlex160
İncele - MakaleYalnız künye2018Scopus SJRQ2Investigation of the effect of RF energy on optical, morphological, chemical and antibacterial properties of PolyTerpenol thin films obtained by RF-PECVD technique
Bayram, Ozkan; Simsek, Onder
In this study, it was aimed to obtain PolyTerpenol thin films by radio frequency plasma enhanced chemical vapor deposition technique using Terpinen-4-ol essential oil, which is organic compounds. The surface morphology and chemical properties of polymer thin films were investigated by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy. AFM analyzes of PolyTerpenol thin films revealed that the thin films are homogeneous, smooth and nonporous. The optical properties of the thin films were determined using UV–Vis spectrophotometer. When optical band gaps of thin films were examined, it was found that this value varied from 3.83 to 3.20 eV. The extinction coefficients of the obtained thin films according to the increasing RF energy were calculated as 0.0011, 0.0060, 0.0085 and 0.0150, respectively, at a wavelength of 320 nm. In addition, antibacterial effects of these thin films against Escherichia Coli (E.Coli) bacteria were also investigated. The PolyTerpenol thin films were found to have high antibacterial activity against E. Coli bacteria.
AtıfScopus8WoS8OpenAlex11İncele - MakaleYalnız künye2018Scopus SJRQ2X-ray CT monitoring of macro void development in mortars exposed to sulfate attack
Tekin, Ilker; Birgul, Recep; Aruntas, Huseyin Y.
This study reports the results of nondestructive monitoring of macro void developments in mortars manufactured with both ordinary Portland cement and sulfate resistant cement. Two types of curing were utilized; tap water curing and another curing environment that contains 5% Na2(SO4) solution. Being the primary objective of this study, macro void developments of the mortar specimens were monitored by X-ray Medical Computerized Tomography. Compressive strength tests and water absorption tests were conducted on specimens that were kept in both curing environments for a duration of 560 days. Data analyses yielded consistent results among the three tests used in this experimental study. Macro void ratios of mortars decreased at the beginning of experiments for a certain period; afterwards, macro void ratios increased. The objective of this study was accomplished as anticipated since X-CT image analysis was able to nondestructively monitor macro void development process in cement mortars.
AtıfScopus6WoS6OpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ1Stochastic responses of isolated bridge with triple concave friction pendulum bearing under spatially varying ground motion
Yurdakul, Muhammet; Ates, Sevket
This study aims to investigate the stochastic response of isolated and non-isolated highway bridges subjected to spatially varying earthquake ground motion model. This model includes wave passage, incoherence and site response effects. The wave passage effect is examined by using various wave velocities. The incoherency effect is investigated by considering the Harichandran and Vanmarcke coherency model. The site response effect is considered by selecting homogeneous firm, medium and soft soil types where the bridge supports are constructed. The ground motion is described by power spectral density function and applied to each support point. Triple concave friction pendulum (TCFP) bearing which is more effective than other seismic isolation systems is used for seismic isolation. To implement seismic isolation procedure, TCFP bearing devices are placed at each of the support points of the deck. In the analysis, the bridge selected is a five-span featuring cast-in-place concrete box girder superstructure supported on reinforced concrete columns. Foundation supported highway bridge is regarded as three regions and compared its different situation in the stochastic analysis. The stochastic analyses results show that spatially varying ground motion has important effects on the stochastic response of the isolated and non-isolated bridges as long span structures.
AtıfScopus13WoS13OpenAlex6İncele - MakaleYalnız künye2018Scopus SJRQ2Determining the Patient-Specific Optimum Osteotomy Line for Severe Mandibular Retrognathia Patients
Şensoy, Abdullah Tahir; Kaymaz, Irfan; Ertaş, Ümit; Kiki, Ali
Purpose: The purpose of this study is to suggest a patient-specific osteotomy line to optimize the distractor position and thus to minimize the disadvantages of conventional mandibular distraction osteogenesis (MDO) protocols. In addition, this study also aims to compare the conventional MDO protocols with the new MDO protocol proposed in this study in terms of both orthodontic outcomes and mechanical effects of osteotomy level on callus stabilization by means of the finite element method. Methods: A preoperative patient-specific 3-dimensional bone model was created and segmented by using computed tomography images of an individual patient. Virtual orthodontic set-up was applied to the segmented model prior to the virtual surgery. In order to compare the proposed osteotomy line with the conventional lines used in clinical applications, virtual surgery simulations were performed and callus tissues were modelled for each scenario. The comparison of the success of each osteotomy line was carried out based on the occlusion of the teeth. Results: The osteotomy line determined using the method proposed in this study has resulted in far less malocclusion than the conventional method. Namely, any angular deviation from the optimum osteotomy line determined in this study might result in deep-bite or open-bite. On the other hand, the finite element analysis results have indicated that this deviation also negatively affects the callus stability. Conclusion: In order to achieve a better MDO treatment in terms of occlusion of the teeth and the callus stability, the location of the osteotomy line and the distractor position can be computationally determined. The results suggest that MDO protocol developed in this study might be used in clinic to achieve a better outcome from the MDO treatment.
AtıfScopus7WoS4OpenAlex8İncele - MakaleYalnız künye2018Scopus SJRQ1Influence of high pressure torsion-induced grain refinement and subsequent aging on tribological properties of Cu-Cr-Zr alloy
Purcek, G.; Yanar, H.; Shangina, D.V.; Demirtas, M.; Bochvar, N.R.; Dobatkin, S.V.
Effects of ultrafine grain formation via high pressure torsion (HPT) and precipitation during aging on the microstructure, mechanical and tribological properties of a Cu-Cr-Zr alloy have been investigated systematically. HPT results in the formation of ultrafine-grained (UFG) structure in the alloy with an average grain/subgrain size of 155 nm which leads to remarkable improvement in its hardness and strength along with a reduction in elongation to failure. Aging of UFG alloy brings about further strengthening due to the precipitation. UFG formation by HPT increases substantially the wear resistance of Cu-Cr-Zr alloy and reduces the friction coefficient. The highest wear resistance and the lowest friction coefficient are obtained on the sample processed by HPT and subsequent aging. The dominant wear mechanism of the alloy varies depending on the applied processes. Adhesion with smearing is the predominant wear mechanism for the initial (warm extruded) samples having coarse-grained (CG) structure. UFG samples show less adhesional effect with less smearing, and a higher tendency to the formation of cracks, abrasion and delamination seem to be dominant in those samples. Oxidative wear mechanism is also operative in both CG and UFG alloy samples. It may be concluded from this study that a combined process including UFG formation by HPT and subsequent precipitation by artificial aging provides a simple and effective processing procedure for improving the strength, hardness and wear resistance of Cu–Cr–Zr alloys without modification of the chemical composition.
AtıfScopus96WoS91OpenAlex99İncele - MakaleYalnız künye2018Scopus SJRQ3Energy and exergy analysis of a solid-oxide fuel cell power generation system for an aerial vehicle (ISSA- 2015–139)
Genç, Gamze; Sarikoç, Selçuk
This paper presents the performance of the solid-oxide fuel cell/gas turbine hybrid power generation system with heat recovery waste unit based on the energy and exergy analyses. The effect of air inlet temperature and air/fuel ratio on exergy destruction and network output is determined. For the numerical calculations, air inlet temperature and air fuel ratio are increased from 273 to 373 K and from 40 to 60, respectively. The results of the numerical calculations bring out that total exergy destruction quantity increases with the increase of air inlet temperature and air/fuel ratio. Furthermore, the maximum system overall first and second law efficiencies are obtained in the cases of air inlet temperature and air/fuel ratio equal to 273 K and 60, respectively, and these values are 62.09% and 54.91%.
AtıfScopus9WoS9OpenAlex12İncele - Derleme MakaleYalnız künye2018Scopus SJRQ1Green roofs and facades: A comprehensive review
Besir, Ahmet B.; Cuce, Erdem
Based on United Nations Environment Program (UNEP), building sector accounts for 40% of total energy consumption. In European countries, 36% of total greenhouse gas emissions is attributed to buildings. In this respect, green roofs are considered to be one of the most appropriate sustainable solutions to resolve the urban heat island-related issues. Roofs account for nearly 20–25% of overall urban surface areas. Energy saving, thermal insulation, shading and evapotranspiration features highlight the key role of green roofs in overall thermal performance of buildings and microclimatic conditions of indoor environments. Within the scope of this research, the concept of green roofs and facades is comprehensively analysed in a holistic and thematic way. Following a historical overview of the technology, the research is split into various subfields such as energy saving in buildings through greenery systems, multifunctional thermal benefits including evapotranspiration, thermal insulation, shading and thermal comfort features, evaporative cooling for reducing cooling demand and minimising wind driven convection losses. The results achieved from the literature survey clearly indicate that green roofs and facades are key solutions to mitigate building-related energy consumptions and greenhouse gas emissions. According to the previous works, heat flow through the building roofs in summer can be reduced by approximately 80% via green roofs. The green roofs are reported to consume less energy in the range of 2.2–16.7% than traditional roofs during summer time. A similar tendency is observed for the winter season depending on regional and climatic conditions. The temperature difference between conventional and greens roofs in winter is found to be about 4 °C, which is remarkable. Energy demand of buildings in summer is highly dependent on the plant intensity as it is reported to be 23.6, 12.3 and 8.2 kWh/m2/year for extensive, semi-intensive and intensive greenery surface, respectively. Greenery systems are also capable of providing thermally comfortable indoor and outdoor conditions. It is underlined that the annual average accumulation of CO2 reaches the level of 13.41–97.03 kg carbon/m2 for 98 m2 of vertical greenery system. The results of this research can be useful for dwellers, builders, architects, engineers and policy makers to have a good understanding about the potential of green roofs and facades to mitigate building-related energy consumptions and carbon emissions in a renewable, sustainable, energy-efficient and cost effective way.
AtıfScopus547WoS435OpenAlex617İncele