Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Zaman, Tolga(3)
- Iftikhar, Soofia(2)
- Akbulut Özen, Songül(1)
- Akinoglu, Bulent G.(1)
- Alamgir(1)
- Arya, Diksha(1)
- Dincer, Ibrahim(1)
- Gonzalez, J(1)
- Kucuk, Haydar(1)
- Martinez, V(1)
- Midilli, Adnan(1)
- Sharma, Prayas(1)
- Turan, Rasit(1)
- Yadav, Subhash Kumar(1)
- Çakmak, Eyüp(1)
- Çelik, Necati(1)
- Özdemir, Atilla(1)
- Özden, Talat(1)
- Özen, Murat(1)
- Şahin Murat Yegin(1)
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ2CsPbBr3 single-crystal growth by temperature-lowering method as a case study for EGS4 benchmarking against commercial radiation detectors
Akbulut Özen, Songül; Özen, Murat; Çelik, Necati
CsPbBr3 single-crystals were synthesized using a hydrobromic acid–based temperature-lowering method, and their structural and optical properties were confirmed by XRD, DSC, and UV–Vis analyses. A solubility curve was established to optimize growth conditions, enabling enlargement of the seeded crystals. The radiation detection potential of CsPbBr3 was evaluated using EGS4 Monte Carlo simulations across photon energies ranging from 10 keV to 1 MeV. Simulated full-energy peak efficiencies and resolution values were compared with conventional detectors (Si(Li), NaI, and HPGe) and with alternative perovskite derivatives (CH3NH3PbBr3, Cs4PbBr6, CsPb2Br5). CsPbBr3 exhibited efficiency scaling with detector volume and resolution behavior consistent with the statistical 1/√E dependence typical of direct-gap semiconductors. While HPGe maintained superior intrinsic resolution, CsPbBr3 offered promising room-temperature performance without cryogenic requirements. These results demonstrate that the temperature-lowering method provides a viable route to scalable CsPbBr3 single-crystals and confirm their potential as cost-effective, high-Z semiconductor detectors for X- and γ-ray applications. The findings establish a foundation for the further optimization of perovskite-based radiation detection technologies.
- MakaleYalnız künye2026Scopus SJRQ1A logarithmic-type estimator for finite population variance and its efficiency properties
Iftikhar, Soofia; Alamgir; Zaman, Tolga
This study proposes a novel logarithmic-type estimator for the finite population variance. We derive the mean square error (MSE) expressions, approximated to the first order, along with the associated efficiency conditions for the proposed estimator, as well as for several existing estimators from the literature. A comprehensive simulation study is conducted to compare the efficiency of the new estimator against these established methods. Based on the analysis of a real dataset, the results demonstrate that the proposed estimator achieves the minimum mean square error and satisfies all relevant efficiency criteria. Consequently, it is concluded that the proposed estimator outperforms the other considered estimators in terms of efficiency.
- MakaleYalnız künye2026Scopus SJRQ3Improved generalized ratio estimators of population mean using auxiliary variables
Yadav, Subhash Kumar; Arya, Diksha; Sharma, Prayas; Zaman, Tolga
The Quest for the improved estimators of population mean is a continuous process to estimate it more efficiently and more closely to the true population mean of the study variable. There are various estimators of population mean in the literature, which estimate it efficiently, but still there is space for more efficient estimators. For improved estimation of population mean of primary variable, we suggest six different searls type ratio estimators utilizing the known auxiliary parameters. We derive the expressions for the biases and the mean squared errors of the introduced estimators for an approximation of degree one. The optimal values of the Searls characterizing constants, which minimize the mean squared errors of the introduced estimators, are obtained. The least value of the mean squared error of the proposed estimators for these optimal values of the characterizing scalars is also acquired. The efficiency of the proposed estimators is compared theoretically with the competing estimators of population mean through their mean squared errors. We derive the efficiency conditions of the proposed estimator for which it is more efficient than the estimators of population mean in competition. These efficiency conditions of the proposed estimators are verified through empirical data and the improvement over the competing estimators is calculated based on the minimum values of the mean squared errors. It is evident from the numerical study that the proposed estimator has the least mean squared error and the highest percentage relative efficiency in comparison to competing estimators. Thus, the proposed estimators are recommended for applications in different areas of applications.
AtıfScopus2İncele - Yüksek Lisans TeziAçık Erişim2023Karadeniz Bölgesi'ndeki belediyelerin etkinliklerinin veri zarflama analizi ile değerlendirilmesi
Şahin Murat Yegin
Belediyeler, sorumlu oldukları halka şehircilik hizmetlerinden eğitim ve kültür hizmetlerine kadar çok çeşitli hizmetler vermektedirler. İdari ve mali özerkliğe sahip kamu tüzel kişiliği olan yerel yönetim birimleri içinde en aktif, görev ve hizmet alanı en geniş birimler belediyelerdir. Yerel yönetimlerin tamamı kaynak sıkıntısı yaşamakla birlikte belediyeler kaynak sıkıntısının etkisini daha fazla yaşamaktadır. Bunun nedenleri arasında bilimsel ve teknolojik gelişmelerin neden olduğu sosyal hareketlilik, sosyal, kültürel ve sportif nitelikli uğraşı alanların ortaya çıkması, kentsel alandaki nüfus artışı, sosyo-ekonomik iş bölümü ve katmanlaşmanın artması gibi faktörlerin halkın ihtiyaç ve beklentilerinin de çeşitlenmesine, dolayısıyla belediyelerin görev ve hizmet alanlarının genişlemesine yol açmasıdır. Bu çalışmanın amacı, Karadeniz Bölgesi'nde bulunan 18 ildeki belediyenin 2019 yılına ait girdi ve çıktı değerlerine göre birbirlerine kıyasla etkinliklerinin Veri Zarflama Analizi (VZA) yöntemi kullanılarak belirlenmesidir. Girdi değerleri olarak personel giderleri, mal ve hizmet alım giderleri, sermaye giderleri; çıktı değerleri olarak ise vergi gelirleri, teşebbüs ve mülkiyet gelirleri ve diğer gelirler belirlenmiştir. Yapılan analizlerin sonucunda belediyelerin kaynaklarını etkin bir şekilde kullanıp kullanmadığı tespit edilecektir.
- MakaleAçık Erişim2023A NEW LOGARITHMIC RATIO TYPE ESTIMATOR OF POPULATION MEAN FOR SIMPLE RANDOM SAMPLING: A SIMULATION STUDY
Zaman, Tolga; Iftikhar, Soofia
This paper provides a logarithmic ratio type estimator of a finite population mean using an auxiliary variable in simple random sampling. The expression for the mean square error (MSE) of the proposed estimator and some selected estimators are calculated along with the theoretical conditions. Further the numerical comparisons and simulation study based on different probability distributions supports the claim that the proposed estimator performs better as compared to the ones used in this study.
AtıfWoS6OpenAlex8İncele - BildiriAçık Erişim2017Effect of Ambient Conditions on Monthly Performances of Three Different PV Arrays
Özden, Talat; Akinoglu, Bulent G.; Turan, Rasit; Martinez, V; Gonzalez, J
Solar PV cells may be mainly divided into two parts as crystalline and thin film. Mono-crystalline silicon (e.g. Mono-Si) and microcrystalline based amorphous silicon and other thin films (e.g. gc-Si/a-Si and CdTe thin films) are widely used PV cells in the arrays. The outdoor performances of these systems depend on some climatic parameters and conditions, and it is important to understand how the monthly efficiencies vary with these parameters. In the present study, the data obtained from three grid connected PV arrays of Mono Si, a-Si/p.c-Si and CdTe thin film that were operated for 41 months in Ankara-Turkey is analyzed. The results showed that Mono-Si an-ay performance depends on the 5 parameters of outdoor climatic conditions while a-Si/gc-Si and CdTe thin film arrays performances arc not significantly affected by the variation of the climatic parameters. The possible reasons are discussed in details.
- MakaleYalnız künye2010Scopus SJRQ1Exergetic performance analysis of a recirculating aquaculture system
Kucuk, Haydar; Midilli, Adnan; Özdemir, Atilla; Çakmak, Eyüp; Dincer, Ibrahim
This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period.
AtıfScopus16WoS13OpenAlex26İncele