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Article Citation - WoS: 6A Light Bulb in Every House the Istanbul General Electric Factory and American Technology Transfer To Turkey(Johns Hopkins Univ Press, 2022) Tunc, Tanfer Emin; Tunc, GokhanIn 1946, Turkish entrepreneur Vehbi Koc signed an agreement with the U.S. firm General Electric to build and operate its first light bulb factory in the Near/Middle East, in Istanbul. This private joint venture introduced new manufacturing techniques, business practices, and consumer habits to Turkey, opening channels of postwar technological exchange. Closer examination of the GE-Koc partnership reveals that during the early Cold War, the transfer and embedding of American technologies in Turkey was a politically complicated process of innovation that required constant adaptation. Fraught with unforeseeable obstacles, it also required cautious negotiation with multiple transnational actors. The story of the GE-Koc partnership thus adds a new dimension to historical understandings of the Turkish Cold War experience and the Americanization of the region. It illustrates how transferring a nonmilitary, soft-power, domestic technologythe light bulb-played a significant role in Turkish-American relations and therefore contributes to studies of U.S. Cold War diplomacy through transnational investment in innovation.Article Citation - WoS: 1Citation - Scopus: 1The Effect of Group Behavior on the Pull-Out Capacity of Model Soil Nails in High Plasticity Clay(Springer int Publ Ag, 2024) Akis, Ebru; Bakir, Bahadir Sadik; Yilmaz, Mustafa TolgaSoil nailing technique is widely used in stabilizing roadway and tunnel portal cut excavations. The key parameter in the design of soil nail systems is the pull-out capacity. The pull-out capacity of soil nails can be estimated either from the studies involving similar soil conditions or from the empirical formulas available in the literature. Particularly, it has been documented placing nails closer than a certain minimum distance results in a reduction in the pull-out resistance of a nail placed in sand. However, this requirement has not been discussed for the nail groups located within clay formations. In order to investigate the influence of nail spacing on the pull-out resistance of nails, a series of laboratory pull-out experiments were performed in clay of high plasticity. The results of these experiments showed a remarkable trend. Specifically, there was a significant reduction in the pull-out capacity of a nail when the spacing between nails two times the nail diameter (2 & Oslash;). In contrast, the pull-out capacity of a nail embedded in clay remained unaffected by neighboring nails, provided the spacing was maintained at six times the nail diameter (6 & Oslash;). In addition, during the conducted pull-out tests, it was observed that the failure mode of a single nail and 6 & Oslash; spaced group nails near the surface results as heaving around the single nail. However, in the case of closely positioned (2 & Oslash; spaced) nails, the affected area following nail failure exhibits distinct characteristics, which operate as a group. This leads to the occurrence of failure in the form of heaving around the group of nails.Review Citation - WoS: 57Citation - Scopus: 65Application of Minimum Quantity Lubrication Techniques in Machining Process of Titanium Alloy for Sustainability: a Review(Springer London Ltd, 2019) Osman, Khaled Ali; Unver, Hakki Ozgur; Seker, UlviRecently, the manufacturing sector is increasingly keen to apply sustainability at all levels of sustainability from system to products and processes. At the processes level, cutting fluids (CFs) are among the most unsustainable materials and need to be addressed properly in accordance with three main and decisive aspects, also known as the triple bottom line: ecology, society, and economics. Minimum quantity lubrication (MQL) is a promising technique that minimizes the use of CFs, thus improving sustainability. This paper presents a review of the literature available on the use of the MQL technique during different machining processes involving titanium alloys (Ti-6Al-4V). To carry out the study, four search engines were used to focus on the most cited articles published over a span of 17years from 2000 to 2016. The performance and drawbacks are compiled for each eco-friendly technique: dry, MQL, and cryogenics with combinations of MQL and cryogenics, critically considering machining parameters such as cutting speed, feed rate, and output measures, namely surface roughness, tool life, and cutting temperature. After drawing conclusions from critical evaluation of research body, future research avenues in the field are proposed for the academics and industry.Article Citation - WoS: 19Citation - Scopus: 19A Study on the Dark and Illuminated Operation of Al/Si3< Schottky Photodiodes: Optoelectronic Insights(Springer Heidelberg, 2024) Surucu, Ozge; Yildiz, Dilber Esra; Yildirim, MuratThis work extensively investigates the operation of an Al/ Si3N4/p-Si Schottky-type photodiode under dark and varying illumination intensities. The photodiode is fabricated by employing the metal-organic chemical vapor deposition (MOCVD) method. A thorough electrical characterization is performed at room temperature, encompassing measurements of current-voltage (I-V), current-time (I-t), capacitance-time (C-t), and conductance time (G-t). The photodiode's rectification factor and reverse bias area increased under illumination. The relationship between light power density, barrier height, and diode ideality factor is found. The study also found a strong correlation between light intensity and applied voltage on series resistance (R-s) and shunt resistance (R-sh). R-s values are calculated using Cheung's functions, revealing the diode's resistance behavior. The study also examines the photodiode's photoconductivity and photoconductance, finding a non-linear relationship between photocurrent and illumination intensity, suggesting bimolecular recombination. Calculated photosensitivity (K), responsivity (R), and detectivity (D*) values show the device's light response effectiveness, but efficiency decreases at higher illumination intensities. Transient experiments indicate stable and reproducible photocurrent characteristics, revealing photogenerated charge temporal evolution. This study provides a complete understanding of the Al/Si3N4/p-Si Schottky photodiode's behavior under different illumination intensities. The findings advance optoelectronic device knowledge and enable their use in advanced technologies.Article Citation - WoS: 10Citation - Scopus: 9Cohomology of Sheaves of Frechet Algebras and Spectral Theory(Pleiades Publishing inc, 2005) Dosiev, AAWe propose a holomorpbic functional calculus for a noncommutative operator family generating a supernilpotent Lie subalgebra. This calculus extends Taylor's holomorphic functional calculus.Conference Object Citation - WoS: 5Citation - Scopus: 3Evaluation of Efficiencies of Diffuse Allochthonous and Autochthonous Nutrient Input Control in Restoration of a Highly Eutrophic Lake(I W A Publishing, 2002) Muhammetoglu, A; Muhammetoglu, H; Soyupak, SMogan Lake is an important recreational area for Metropolitan Ankara-Turkey. It is a shallow eutrophic lake with a dense growth of macrophytes. The main contributors of nutrients and other pollutants to the lake are the creeks carrying the runoff water from the watershed and upland farming land, in addition to the domestic and industrial wastewater discharges from a nearby town and industries. Hydrodynamic and water quality modeling techniques were used to determine the optimum management schemes for the lake restoration and diffuse pollution control. Management scenarios were devised and tested to control allochthonous and autochthonous nutrient inputs to the lake. Phosphorus and nitrogen load reductions were the main test elements for the control of allochthonous nutrient inputs. The scenario analysis revealed that reduction of phosphorus and nitrogen loads from diffused sources will have a marginal effect on controlling eutrophication if macrophyte growth is left uncontrolled. Scenarios employing macrophyte harvesting and sediment dredging have been evaluated for autochthonous nutrient input control. Sediment dredging alone has been shown to yield the most favorable conditions for water quality improvement in Mogan Lake. Further, control of diffuse pollution was an essential final step to achieve an acceptable long-term sustainable water quality improvement in the lake.Article Citation - Scopus: 3Complete Characterization of a Class of Permutation Trinomials in Characteristic Five(Springer, 2024) Grassl,M.; Özbudak,F.; Özkaya,B.; Temür,B.G.In this paper, we address an open problem posed by Bai and Xia in [2]. We study polynomials of the form f(x)=x4q+1+λ1x5q+λ2xq+4 over the finite field F5k, which are not quasi-multiplicative equivalent to any of the known permutation polynomials in the literature. We find necessary and sufficient conditions on λ1,λ2∈F5k so that f(x) is a permutation monomial, binomial, or trinomial of F52k. © The Author(s) 2024.Article Citation - WoS: 1Citation - Scopus: 1Personal Response Systems Through the Prism of Students' Experiences(Wiley, 2020) Mishra, Deepti; Chew, Esyin; Ostrovska, Sofiya; Wong, JojoPersonal response systems (PRSs) today offer an opportunity to the field of education in terms of improving teaching and learning outcomes through active engagement in classrooms. The present paper investigates students' attitudes to different types of PRSs, namely, Socrative and Clickers. Both qualitative and quantitative data are gathered and classified. The performed thematic analysis reveals major categories within the framework of this study, namely educational efficacy, psychological aspects, technology-related issues, and administrative issues. It has been found that Socrative fares better in the "educational efficacy" and "administrative issues," whereas Clickers outperforms Socrative in the "technological-related issues." It is worth pointing out that both Socrative and Clickers are tantamount in "psychological aspects" yielding no negative experiences. The results of this study reveal that two main factors, cost and technological infrastructure, are determinative in the incorporation and appreciation of such systems in an educational setting.Article Citation - WoS: 20Citation - Scopus: 26Simplified software inspection process in compliance with international standards(Elsevier Science Bv, 2009) Mishra, Deepti; Mishra, AlokA significant amount of software is developed all over the world by small and medium size software organizations. These organizations do not have enough infrastructures and resources to implement an austere quality plan. Software inspection is a fundamental component of the software quality assurance process. Formal review methods are rigorous and their implementation is cumbersome for small and medium enterprises. In this paper, we have presented a new simplified inspection process which is easy to implement. requires fewer resource and almost no documentation. Also, people who are conducting this inspection need not be present at the same place during most stages of the inspection process. We have also compared this process with IEEE and NASA standards for software inspection and found that it meets almost 99% of both standards. While there has been much research on inspection, little attention is paid towards compliance with international standards. These results could be used as a basis for further research in software inspection and process towards aligning with international standards. This process has been successfully implemented in a CMM level 3 software development organization which is striving to accomplish higher maturity levels to establish at the international level. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 3Using Servo-Drive Presses to Determine the Effect of Blank Holder Pressure on Temperature Change in Warm Forming of Sheet(Asme-amer Soc Mechanical Eng, 2011) Kaya, SerhatHeat transfer coefficient (HTC) is one of the most important and difficult-to-obtain parameter in high temperature environment. Contact pressure and workpiece surface roughness are among important parameters that affect the heat transfer in elevated temperature forming of sheets. In this study, HTCs are investigated experimentally by using a servo-drive press. With the flexibility that the servo-drive press offers, effect of various blank holder pressures on temperature change is determined. Before and after surface roughness conditions of aluminum and magnesium (from two different manufacturers) alloy sheets are compared. Experimental setup was modeled using deform 2D, and measured temperature curves were compared with the finite element analysis (FEA) predictions and a window of heat transfer coefficients were determined for warm forming of sheets. Determined heat transfer coefficients were implemented in a nonisothermal deep drawing FE model in deform 2D and results were compared with experiments. Good agreement was obtained between FEA predictions and experiments.
