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Article Citation - WoS: 6Citation - Scopus: 103-D Dynamic Uav Base Station Location Problem(informs, 2021) Cicek, Cihan Tugrul; Shen, Zuo-Jun Max; Gultekin, Hakan; Tavli, Bulent; Industrial Engineering; 06. School Of Engineering; 01. Atılım UniversityWe address a dynamic covering location problem of an unmanned aerial vehicle base station (UAV-BS), in which the location sequence of a single UAV-BS in a wireless communication network is determined to satisfy data demand arising from ground users. This problem is especially relevant in the context of smart grid and disaster relief. The vertical movement ability of the UAV-BS and nonconvex covering functions in wireless communication restrict utilizing classical planar covering location approaches. Therefore, we develop new formulations to this emerging problem for a finite time horizon to maximize the total coverage. In particular, we develop a mixed-integer nonlinear programming formulation that is nonconvex in nature and propose a Lagrangean decomposition algorithm (LDA) to solve this formulation. Because of the high complexity of the problem, the LDA is still unable to find good local solutions to large-scale problems. Therefore, we develop a continuum approximation (CA) model and show that CA would be a promising approach in terms of both computational time and solution accuracy. Our numerical study also shows that the CA model can be a remedy to build efficient initial solutions for exact solution algorithms. Summary of Contribution: This paper addresses a facet of mixed integer nonlinear programming formulations. Dynamic facility location problems (DFLPs) arise in a wide range of applications. However, classical DFLPs typically focus on the two-dimensional spaces. Emerging technologies in wireless communication and some other promising application areas, such as smart grids, have brought new location problems that cannot be solved with classical approaches. For practical reasons, many research attempts to solve this new problem, especially by researchers whose primary research area is not OR, have seemed far from analyzing the characteristics of the formulations. Rather, solution-oriented greedy heuristics have been proposed. This paper has two main objectives: (i) to close the gap between practical and theoretical sides of this new problem with the help of current knowledge that OR possesses to solve facility location problems and (ii) to support the findings with an exhaustive computational study to show how these findings can be applied to practice.Article 3-D Gravity Modeling of the Kars Basin as a Hidden Extension of the Caspian Petroleum System, Ne-Anatolia, Turkey(Springer Basel Ag, 2024) Aydemir, Attila; Bilim, Funda; 01. Atılım UniversityThe Kars Basin in northeastern Turkey is closely related to the Caspian Petroleum System but it is hidden by a great extent of volcanic rocks. The Oligo-Miocene Komurlu Formation within the basin is the Turkish equivalent of the Maikopian Formation which is the main source rock in the Caspian region. Although the Kars Basin has considerable hydrocarbon potential it is one of the least explored basins in Turkey and there is only a limited literature on the region. This study is the first comprehensive investigation to determine the basement geometry, depth, internal structure and basin boundaries. Gravity data and power spectrum analysis were used in this study. The gravity anomalies were low-pass filtered and the average depth of the basin is found to be approximately 5 km. Boundaries of the basin are entirely confined within the Turkish territorial borders. The basin geometry is remarkably consistent with the crustal thickness geometry across the region and the maximum crustal thickness is 42 km, indicating that the basin was formed on the thickest part of the crust in the region. A 3-D model of the Kars Plateau indicates that the Kars Basin is made up of four different deep (> 6 km) depressions forming a channel-like trend from southwest to northeast from the Horasan area to the Arpacay area. There are four less deep sections (< 6 km) to the north of this trend. The depressions in the north are separated by the Allahuekber Mountains that are marked by a distinctive magnetic anomaly, from the deep SW-NE trend. High-standing regions between the depressions could be prospective areas for the oil accumulation.Article A Factory in a Time of Turmoil: The Establishment and Engineering of the Büyükdere Match Factory in 1930s Istanbul(MDPI, 2025) Tunc, Gokhan; Tunc, Tanfer Emin; Civil Engineering; 06. School Of Engineering; 01. Atılım UniversityThe Republic of Turkey established its first match factory in Sinop in 1929 but had to relocate it even before it was in operation due to severe structural damage caused by ground settlement. In July 1930, through his US-based firm the American-Turkish Investment Corporation (ATIC), the Swedish "Match King" Ivar Kreuger signed a contract with the Republic of Turkey to build and operate a factory in B & uuml;y & uuml;kdere, Istanbul. By 1930, Kreuger had already established a match production monopoly in nearly every country in Europe and that year created a similar financial system for Turkey, gaining control of match production for 25 years. This article explains the events surrounding the establishment of his modern production facility in Turkey, with a particular focus on its engineering aspects. It details the strategically chosen location, the engineering solutions for the factory's construction, its production lines, and what the country gained and lost from it. In order to determine the establishment and production processes of the facility, the authors examined domestic and foreign archival documents, firsthand news reports from the period, articles and theses, and all other available documents. After the contract was terminated by both parties, the Turkish government and ATIC, in May 1943, the factory continued its production and storage activities until May 1989. At that point, the factory and all its equipment were integrated into another existing facility in the & Idot;neg & ouml;l district of Bursa province. Almost all the buildings of the B & uuml;y & uuml;kdere Match Factory were demolished, and the land was repurposed for a 450-bed regional hospital in 2012. In short, this article deploys the B & uuml;y & uuml;kdere Match Factory as a case study to examine what Turkey gained and lost from the establishment and production processes of a modern industrial factory, enabled by US-Turkish collaboration, and equipped with the most advanced manufacturing and engineering technologies of the time.Article A New Conservative Numerical Method for Strongly Coupled Nonlinear Schrödinger Equations(Springer Heidelberg, 2025) Ors, Ridvan Fatih; Koroglu, Canan; Aydin, Ayhan; Mathematics; 02. School of Arts and Sciences; 01. Atılım UniversityIn this paper, a numerical method based on the conservative finite difference scheme is constructed to numerically solve the strongly coupled nonlinear Schr & ouml;dinger (SCNLS) equation. Conservative properties such as energy and mass of the SCNLS equation have been proven. In particular a fourth-order central difference scheme is used to discretize the the spatial derivative and a second-order Crank-Nicolson type discretization is used to discretize the temporal derivative. It has been shown that the proposed scheme preserves the discrete mass and energy. The existence of discrete solution is also investigated. Several numerical results are given to demonstrate the preservation properties of the new method. Also, the effect of the linear coupling parameters on the evolution of solitary waves is investigated.Article Citation - WoS: 1Citation - Scopus: 1Ab Initio Study of Structural and Electronic Properties of Single Crystal and Core/Shell Ii-Vi Semiconductor Nanowires(Elsevier, 2016) Pekoz, R.; Department of Electrical & Electronics Engineering; 15. Graduate School of Natural and Applied Sciences; 01. Atılım UniversityStructural and electronic properties of pristine and H-passivated wurtzite type ZnSe, ZnTe nanowires and ZnX/ZnY (X = Se(Te) and Y = Te(Se)) core/shell nanowires oriented along the [0001] direction have been investigated using first-principles calculations. The changes in the electronic structure of the nanowires due to the quantum confinement and morphology have been searched. Quantum confinement increases the band gap energy as the diameters of ZnSe and ZnTe nanowires decrease. Both homostructured and heterostructured nanowires are found to show a semiconducting character with direct band gaps at Gamma-point. Changing the morphology from homostructured nanowires to heterostructured core/shell nanowires has an important impact on the electronic structure. For instance, the charge separation of electrons and holes along the infinite direction of core/shell nanowires shows a strong preference for electron(hole) states localized inside ZnSe(ZnTe) regions. (C) 2016 Elsevier B.V. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 5Absorption Edge and Optical Constants of Tl2ga2< Crystals From Reflection and Transmission, and Ellipsometric Measurements(Elsevier, 2012) Isik, M.; Gasanly, N. M.; Department of Electrical & Electronics Engineering; 15. Graduate School of Natural and Applied Sciences; 01. Atılım UniversityThe optical properties of Tl2Ga2S3Se layered crystalline semiconductors were investigated from transmission, reflection and ellipsometric measurements. The experimental results of the room temperature transmission and reflection measurements performed in the wavelength range of 400-1100 nm showed the presence of both indirect and direct transitions in the band structure of the crystals with 2.38 and 2.62 eV band gap energies. Spectroscopic ellipsometry measurements on Tl2Ga2S3Se crystals were carried out on the layer-plane (0 0 1) surfaces with light polarization E perpendicular to c* in the 1.20-4.70 eV spectral range at room temperature. The real and imaginary parts of the dielectric function as well as refractive and absorption indices were found as a result of analysis of ellipsometric data. The Wemple-DiDomenico single-effective-oscillator model was used to study the dispersion of the refractive index in the below band gap energy range. The structures of critical points have been characterized from the second derivative spectra of the dielectric function. The analysis revealed four interband transition structures with 3.14, 3.40, 3.86 and 4.50 eV critical point energies. (C) 2012 Elsevier B.V. All rights reserved.Article Citation - WoS: 31Citation - Scopus: 41Accessibility Evaluation of Top University Websites: a Comparative Study of Kyrgyzstan, Azerbaijan, Kazakhstan and Turkey(Springer Heidelberg, 2018) Ismailova, Rita; Inal, Yavuz; Information Systems Engineering; 06. School Of Engineering; 01. Atılım UniversityIt is important that university websites and services offered through their sites are used effectively, efficiently and satisfactorily by the whole target group of the university, including disabled users. However, universities in many countries are still unable to meet the criteria for web accessibility. This study aimed to test the websites of the top universities in Kyrgyzstan, Kazakhstan, Azerbaijan and Turkey using automated assessment tools. The results showed that university websites are more popular in Turkey, and in Turkish universities developers pay more attention to the performance of websites, followed by websites of Azerbaijani, Kyrgyz and Kazakh universities. The majority of the university websites in the study did not meet the WCAG 2.0 accessibility criteria. Only two Kyrgyz and two Kazakh university websites attained conformance level A, and only three, one Kyrgyz and two Kazakh, achieved accessibility conformance level AAA. Based on the results, it was determined that universities included in the present study need to devote more effort to making their websites more accessible for their users.Article Citation - WoS: 30Citation - Scopus: 29Acoustic Control of Flow Over Naca 2415 Airfoil at Low Reynolds Numbers(Asce-amer Soc Civil Engineers, 2016) Genc, M. Serdar; Acikel, H. Hakan; Akpolat, M. Tugrul; Ozkan, Gokhan; Karasu, Ilyas; Airframe and Powerplant Maintenance; 13. School of Civil Aviation (4-Year); 01. Atılım UniversityIn this study, the effects of acoustic excitation frequency on flow over an NACA 2415 airfoil were determined, and all of the experiments were done both with and without the presence of the acoustic excitation. The acoustic excitation was applied for a range of angles of attack (0 degrees-25 degrees) and Reynolds numbers of 50,000, 75,000, 100,000, 150,000, and 200,000. To examine the effects of acoustic excitation on the flow, force measurements, pressure measurements, hot-wire anemometry, smoke-wire flow-visualization, and particle image velocimetry techniques were employed. The results indicated that for stall and some limited poststall angles of attack of the acoustic excitation having a frequency in a certain range forced the separated shear layer to reattach to the surface of the airfoil. As the Reynolds number increased, the effective excitation frequency increased, but the range of Zaman number [St/(R-1/2)] was the same. With the acoustic excitation, the stall angle was delayed from 12 degrees to 16 degrees at R = 50,000, and there was a 30% and 50% increase on the maximum value of the lift coefficient and the ratio of the lift and drag forces, respectively. Moreover, the stall angle was delayed from 13 degrees to 17 degrees at R = 75,000, from 15 degrees to 18 degrees at R = 100,000, from 15 degrees to 17 degrees at R = 150,000. Furthermore, it was concluded that acoustic excitation shrunk laminar separation bubble, and an effect of the acoustic control on the separation bubble decreased as the Reynolds number increased. (C) 2016 American Society of Civil Engineers.Article Citation - WoS: 1Citation - Scopus: 1Adaptive Stimulus Design for Dynamic Recurrent Neural Network Models(Frontiers Media Sa, 2019) Doruk, R. Ozgur; Zhang, Kechen; Electrical-Electronics Engineering; 06. School Of Engineering; 01. Atılım UniversityWe present an adaptive stimulus design method for efficiently estimating the parameters of a dynamic recurrent network model with interacting excitatory and inhibitory neuronal populations. Although stimuli that are optimized for model parameter estimation should, in theory, have advantages over nonadaptive random stimuli, in practice it remains unclear in what way and to what extent an optimal design of time-varying stimuli may actually improve parameter estimation for this common type of recurrent network models. Here we specified the time course of each stimulus by a Fourier series whose amplitudes and phases were determined by maximizing a utility function based on the Fisher information matrix. To facilitate the optimization process, we have derived differential equations that govern the time evolution of the gradients of the utility function with respect to the stimulus parameters. The network parameters were estimated by maximum likelihood from the spike train data generated by an inhomogeneous Poisson process from the continuous network state. The adaptive design process was repeated in a closed loop, alternating between optimal stimulus design and parameter estimation from the updated stimulus-response data. Our results confirmed that, compared with random stimuli, optimally designed stimuli elicited responses with significantly better likelihood values for parameter estimation. Furthermore, all individual parameters, including the time constants and the connection weights, were recovered more accurately by the optimal design method. We also examined how the errors of different parameter estimates were correlated, and proposed heuristic formulas to account for the correlation patterns by an approximate parameter-confounding theory. Our results suggest that although adaptive optimal stimulus design incurs considerable computational cost even for the simplest excitatory-inhibitory recurrent network model, it may potentially help save time in experiments by reducing the number of stimuli needed for network parameter estimation.Article Citation - WoS: 3Citation - Scopus: 6Adult Education as a Stepping-Stone To Better Jobs: an Analysis of the Adult Education Survey in Turkey(Sage Publications inc, 2018) Cilasun, Seyit Mumin; Demir-Seker, Sirma; Dincer, N. Nergiz; Tekin-Koru, Ayca; Department of Business; 17. Graduate School of Social Sciences; 01. Atılım UniversityThe objective of this article is to investigate whether adult education (AE) can be used as a tool in facilitating transitions to/in the labor market, using the cross-sectional Adult Education Survey of Turkey (2012). AE is defined as the nonformal education for individuals aged older than 25 years. The outcome of AE is measured by changing jobs for employed and finding a job for the unemployed. Concentrating on employed people, we analyze both the determinants and the outcome of participation in AE for the purpose of changing jobs; and second, concentrating on unemployed people, we analyze both the determinants and the outcome of participation in AE for the purpose of getting employed. We find that once young males who are already working participate in AE for changing work, independent of their education or how AE is financed, they can be successful in doing so. The results of the paper suggest that AE programs offered by the government can serve as a tool in increasing income of the less educated and the unemployed by facilitating their transition to the labor market.Article Citation - WoS: 7Citation - Scopus: 7Advanced 3d Printed Bone Scaffolds With Sodium Alginate/Tri-calcium Phosphate/Probiotic Bacterial Hydroxyapatite: Enhanced Mechanical and Biocompatible Properties for Bone Tissue Engineering(Elsevier Sci Ltd, 2024) Nouri, Sabereh; Emtiazi, Giti; Ulag, Songul; Gunduz, Oguzhan; Koyuncu, Ayse Ceren Calikoglu; Roghanian, Rasoul; Sasmazel, Hilal Turkoglu; Metallurgical and Materials Engineering; 06. School Of Engineering; 01. Atılım UniversityIntroduction: The increasing prevalence of severe bone diseases, such as osteoporosis and critical bone defects, necessitates the development of more effective bone substitutes. This study addresses this need by investigating 3D-printed bone scaffolds composed of sodium alginate and tricalcium phosphate, enhanced with three distinct types of hydroxyapatite (HA): bovine-derived HA, commercially available HA, and HA enriched with probiotic bacteria. We aim to evaluate the performance of these scaffolds in terms of mechanical strength, biocompatibility, and their ability to support bone regeneration. Methods: The scaffolds were analyzed through various tests, including X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) to characterization. Scanning Electron Microscopy (SEM) was used to examine pore structure, while swelling and degradation tests evaluated the scaffold's stability. Compression testing determined mechanical strength, and in vitro cell culture assays assessed cell proliferation, osteogenic differentiation, and biomineralization. Results: SEM results indicated that 3D scaffolds with probiotic bacterial HA had the desired 472 mu m pore size. These scaffolds demonstrated a strain of 29.26 % and a compressive strength of 10 MPa, meeting the mechanical standards of human trabecular bone. Cell culture studies revealed enhanced cell proliferation by 50 %, osteogenic differentiation with 15.3 U/mg ALP activity, and 1.22-fold biomineralization, suggesting they are highly biocompatible and promote bone growth. Conclusion: Probiotic bacterial HA scaffolds exhibit ideal properties and biocompatibility, enhancing bone regeneration and serving as an ideal alternative to chemical types.Article Citation - WoS: 35Agriculture 4.0: an Implementation Framework for Food Security Attainment in Nigeria's Post-Covid Era(Ieee-inst Electrical Electronics Engineers inc, 2021) Oruma, Samson O.; Misra, Sanjay; Fernandez-Sanz, Luis; Computer Engineering; 06. School Of Engineering; 01. Atılım UniversityThe challenge of Nigeria's food insecurity in the era of the Covid-19 pandemic, insecurity, climate change, population growth, food wastage, etc., is a demanding task. This study addresses Nigeria's food insecurity challenges by adopting agriculture 4.0 and commercial farming. Using data from six digital libraries, the Nigerian Bureau of Statistics, and other internet sources, we conducted a Systematic Literature Review (SLR using PRISMA) on Nigeria's agriculture, food security, and agriculture 4.0. Our results show Nigeria's current agricultural state, threats to food security, and modern digital agriculture technologies. We adapted our SLR findings to develop an implementation framework for agriculture 4.0 in solving Nigeria's food insecurity challenge in the post-Covid-19 era. Our proposed framework integrates precision agriculture in Nigeria's food production and the necessary enabling digital technologies in the agri-food supply chain. We analyzed the critical implementation considerations during each agri-food supply chain stage of farming inputs, farming scale, farming approach, farming operation, food processing, food preservation/storage, distribution/logistics, and the final consumers. This study will help researchers, investors, and the government address food security in Nigeria. The implementation of agriculture 4.0 will substantially contribute to SDG 2 (zero hunger), SDG 3 (good health and well-being), and SDG 8 (decent work and economic growth) of #Envision 2030 of the United Nations, for the benefit of Nigeria, Africa, and the entire world.Article Citation - Scopus: 1Air Refueling Optimisation for More Agile and Efficient Military Deployment Operations(Cambridge Univ Press, 2022) Toydas, M.; Malyemez, C.; 01. Atılım UniversityStrategic airlift is a crucial capability for any country that wants to protect its global interests around the world. Air refueling may offer more agile and efficient airlift capabilities by increasing cargo aircraft payload and shortening airlift time. We investigated whether air refueling can shorten the total time of an airlift operation and decrease the number of cargo aircraft sorties required in a deployment scenario, especially where the distance between origin and destination is within the range of cargo aircraft. We introduced two mathematical models to compare the total airlift time and number of cargo aircraft required for given origin-destination and tanker base locations and total freight to be moved. We optimised initial cargo and fuel amount for cargo aircraft along with rendezvous point coordinates to minimise total airlift time. We used a numerical example to show that substantial airlift time and cargo aircraft sortie savings are possible through air refueling.Article Citation - WoS: 11Citation - Scopus: 13Airport Master Planning in Turkey; Planning and Development Problems and Proposals(Elsevier Sci Ltd, 2013) Saldiraner, Yildirim; Aviation Management; 13. School of Civil Aviation (4-Year); 01. Atılım UniversityThe purpose of this article is to draw attention to the problems experienced during the enlargement and development of existing airport facilities in Turkey, where air transport has been undergoing rapid growth over the past decade, and to provide recommendations to overcome these problems. In this study, civil air transport developments, bottlenecks, trends, and expectations worldwide and in Turkey are investigated. The earliest and latest master plan studies related to Ankara Esenboga, Antalya, Istanbul Ataturk and Sabiha Gokcen, and Izmir Adnan Menderes airports are examined and evaluated and proposals are made regarding the recurring planning problems. The analysis of earlier master plans, which were not brought into effect, indicated that some of the existing applications, such as the co-ordination, planning, and implementation procedures regarding the airport operators/state-regional planning authorities, need to be changed to clear the way for the development of airports. Otherwise, the latest master plans also will not be fully applicable and existing problems will continue to hinder airport development. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 6Al/Cdse Resonant Tunneling Thin Film Transistors(Elsevier Science Bv, 2017) Qasrawi, A. F.; Kayed, T. S.; Elsayed, Khaled A.; Department of Electrical & Electronics Engineering; 15. Graduate School of Natural and Applied Sciences; 01. Atılım UniversityAn Al/CdSe/GaSe/C thin film transistor device was prepared by the physical vapor deposition technique at a vacuum pressure of 10(-5) mbar. The x-ray diffraction measurements demonstrated the polycrystalline nature of the surface of the device. The de current-voltage characteristics recorded for the Al/CdSe/C and Al/CdSe/GaSe/C channels displayed a resonant tunneling diode features during the forward and reverse voltage biasing, respectively. In addition, the switching current ratio of the Al/CdSe/C increased from 18.6 to 9.62x10(3) as a result of the GaSe deposition on the CdSe surface. Moreover, the alternating electrical signal analyses in the frequency range of 1.0 MHz to 1.8 GHz, showed some remarkable properties of negative resistance and negative capacitance spectra of the AVCdSe/GaSe/C thin film transistors. Two distinct resonance-antiresonance phenomena in the resistance spectra and one in the capacitance spectra were observed at 0.53, 1.04 and 1.40 GHz for the Al/CdSe/C channel, respectively. The respective resonating peak positions of the resistance spectra shift to 0.38 and 0.95 GHz when GaSe is interfaced with CdSe. These features of the thin film transistors are promising for use in high quality microwave filtering circuits and also for use as ultrafast switches.Conference Object Aldose Reductase Natural Inhibitors From Ethyl Acetate Extracts From Southern Turkey(Taylor & Francis inc, 2010) Onay, Melih; Coruh, Nursen; Isgor, Belgin; Chemical Engineering; 06. School Of Engineering; 01. Atılım University[No Abstract Available]Article Citation - WoS: 11Citation - Scopus: 19Algorithm for Adaptive Learning Process and Improving Learners' Skills in Java Programming Language(Wiley, 2018) Gavrilovic, Nebojsa; Arsic, Aleksandra; Domazet, Dragan; Mishra, Alok; Software Engineering; 06. School Of Engineering; 01. Atılım UniversityAdaptive approaches within distance learning systems enable adapting teaching process to the needs of each learner during the learning process. This paper presents an algorithm for creating an adaptive learning process that provides knowledge and skills improvement for learners in the Java programming language. Also, it presents the application of the tool that checks the learner's knowledge through solving practical tasks from the Java programming language. The adaptive learning process in this work leads the learner through teaching materials and practical tasks where the acquired knowledge is required to be applied. Also, the algorithm, based on the measurement of knowledge and time spent on a particular part of the learning process with detailed feedback and the demonstration of observed deficiencies, directs the learner to teaching materials that allow improving the demonstrated knowledge. Teaching materials are conceived as learning objects and, as such, allow for the application of adaptive approach. An analysis of the effectiveness of the algorithm and tool for practical knowledge testing from the Java programming language was done with a test group of learners who gave their opinions and grades.Article Citation - WoS: 80Citation - Scopus: 82Amine Grafted Silica Supported Craupd Alloy Nanoparticles: Superb Heterogeneous Catalysts for the Room Temperature Dehydrogenation of Formic Acid(Royal Soc Chemistry, 2015) Yurderi, Mehmet; Bulut, Ahmet; Caner, Nurdan; Celebi, Metin; Kaya, Murat; Zahmakiran, Mehmet; Chemical Engineering; 06. School Of Engineering; 01. Atılım UniversityHerein we show that a previously unappreciated combination of CrAuPd alloy nanoparticles and amine-grafted silica support facilitates the liberation of CO-free H-2 from dehydrogenation of formic acid with record activity in the absence of any additives at room temperature. Furthermore, their excellent catalytic stability makes them isolable and reusable heterogeneous catalysts in the formic acid dehydrogenation.Article Citation - WoS: 1The Amplification of the New Keynesian Models and Robust Optimal Monetary Policy(Amer inst Mathematical Sciences-aims, 2020) Ozcan, Gulserim; Economics; 05. School of Business; 01. Atılım UniversityThis paper analyzes whether and how model uncertainty affects the amplification mechanism of the New Keynesian models in a simple min-max framework where the central bank plays a zero-sum game versus a hypothetical, evil agent. A first finding on a benchmark model with staggered price setting is that a robust optimal commitment policy necessitates more aggressive policy under a demand shock. Further, bringing additional persistence into the model deteriorates the effectiveness of monetary policy. Hence, allowing for either habit formation or partial indexation of prices to lagged inflation rate requires a stronger response for the policy to a demand shock. Together with the specification doubts, in order to reassure the private sector and signal that it will stabilize the fluctuations in the output gap, the policymaker reacts more aggressively as persistence rises. Although inflation persistence does not change the impact of model uncertainty, habit formation in consumption eliminates even reverses the impact of uncertainty on the policy reaction to a supply shock. In all cases, policymaker attributes less importance to nominal interest rate inertia with concerns about model uncertainty.Review Citation - WoS: 220Citation - Scopus: 307Analysing Global Food Waste Problem: Pinpointing the Facts and Estimating the Energy Content(de Gruyter Open Ltd, 2013) Melikoglu, Mehmet; Lin, Carol Sze Ki; Webb, Colin; Energy Systems Engineering; 06. School Of Engineering; 01. Atılım UniversityFood waste is a global problem. Each year food worth billions of dollars is wasted by the developed economies of the world. When food is wasted, the problem does not end at that point. More than 95% of the food waste ends at landfill sites, where converted into methane, carbon dioxide and other greenhouse gasses by anaerobic digestion. The impact of food waste to climate change is catastrophic. Food waste problem tends to increase in next 25 years due to economic and population growth mainly in Asian countries. In addition, when food wastes buried at landfill sites their energy content is lost. Although food waste is a huge problem, its global size and extent has recently become a hot topic in the academic community. This paper summarises the size of the global food waste problem together with the estimation of the amount of energy lost when food wastes dumped at landfill sites. Calculations in this study also revealed that energy lost at landfill sites equals to 43% of the delivered energy used for the preparation of foods in the US, 37% of the hydroelectric power generation of Japan, and more than 100% of the current annual renewable energy demand of UK industries.
