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An alternative distribution to lindley and power lindley distributions with characterizations, different estimation methods and data applications
No full textThis paper proposes a new extended Lindley distribution, which has a more flexible density and hazard rate shapes than the Lindley and Power Lindley distributions, based on the mixture distribution structure in order to model with new distribution characteristics real data phenomena. Its some distributional properties such as the shapes, moments, quantile function, Bonferonni and Lorenz curves, mean deviations and order statistics have been obtained. Characterizations based on two truncated moments, conditional expectation as well as in terms of the hazard function are presented. Different estimation procedures have been employed to estimate the unknown parameters and their performances are compared via Monte Carlo simulations. The flexibility and importance of the proposed model are illustrated by two real data sets
A Non-Dominated Sorting Genetic Algorithm-II-based approach to optimize the spectral and spatial quality of component substitution-based pansharpened images
No full textPansharpening aims to fuse a lower-resolution multispectral (MS) image and a higher-resolution panchromatic image, resulting in an image with the color quality of the former and spatial detail quality of the latter. Of all, the component substitution (CS)-based pansharpening methods have drawn attentions with their ability to produce sharp images. Despite their success in sharpening the images, these methods deteriorate the color features of the input MS images due of the uncertainty in the calculation of the intensity component used by them. Previous studies showed that attempts to preserve the color features tend to cause spatial detail loss to a certain extent. This, of course, reveals the necessity of a compromise between the spectral and spatial fidelity of the pansharpened images produced by the CS-based techniques. This study proposed using the multi-objective Non-Dominated Sorting Genetic Algorithm-II metaheuristic algorithm with the CS-based methods to optimize the intensity component to find the best compromise between the spectral and spatial fidelity of the pansharpened images. The proposed framework was applied on two commonly used pansharpening techniques, Gram-Schmidt and Synthetic Variable Ratio. It was found that the proposed methods managed to find the best balance between the color and spatial fidelity
Investigation of the effect of exercise on high school students' psychological resilience levels in covid-19 pandemic
Get PDFBu araştırmanın amacı, COVID-19 pandemi sürecinde lise öğrencilerinin psikolojik sağlamlık düzeylerini
belirlemek, cinsiyet, egzersiz yapma durumları ve haftalık egzersiz sıklığı açısından incelemektir. Araştırmanın
örneklemini 116 (Xyaş=16.00±0.99) kadın, 107 erkek (Xyaş=16.18±1.06) olmak üzere toplam 223
(Xyaş=16.09±0.81) lise öğrencisi oluşturmaktadır. Veriler “Psikolojik Sağlamlık Ölçeği” ile toplanmıştır.
Verilerin analizinde t testi, tek yönlü ANOVA testi ve pearson korelasyon analizi kullanılmıştır. Araştırmanın
bulguları, kadın katılımcıların psikolojik sağlamlık ölçeği puanının erkek katılımcılardan anlamlı düzeyde daha
yüksek olduğunu ortaya koymaktadır (p<.01). Katılımcıların egzersiz yapma durumları bakımından psikolojik
sağlamlık ölçeği puanının egzersiz yapan katılımcılar lehine anlamlı bulunmuştur (p<.01). Egzersiz yapma
tercihlerine göre katılımcıların psikolojik sağlamlık ölçeği puanı arasında bir fark saptanmamıştır (p> .01).
Ayrıca egzersiz yapan katılımcıların haftalık egzersiz yapma sıklıkları ile psikolojik sağlamlık ölçeği puanları
arasında pozitif bir korelasyon bulunmuştur (p<.01). Sonuç olarak, COVID-19 sosyal izolasyon sürecinde
egzersiz yapan katılımcıların psikolojik sağlamlık düzeylerinin egzersiz yapmayanlara göre daha yüksek olduğu
ortaya çıkmıştır. Bu gibi durumlarda egzersiz yapmanın yararları konusunda toplumun farkındalığının
artırılması için çalışmaların yapılmasına ihtiyaç vardır.The aim of the study is to determine the psychological resilience levels of high school students in the
COVID-19 pandemic, to examine in terms of gender, exercise status and weekly exercise frequency. The sample
of the research consists of 223 (X-age=16.09±0.81) high school students, 116 women (X-age=16.00±0.99) and
107 men (x-age=16.18±1.06). The data were collected with the Psychological Resilience Scale. In the analysis
of the data, t test, one way ANOVA test and pearson correlation analysis were used. The results of the study
reveal that the psychological resilience scale score of female participants is significantly higher than male
participants (p <.01). It was found that there was a significant difference in psychological resilience scale score
in terms of participants' exercise status in favor of exercising participants (p <.01). According to the exercise
preferences, there was no difference between the participants' psychological resilience scale score (p> .01). In
addition, a positive correlation was found between the participants' weekly exercise frequency and
psychological resilience scale scores (p <.01). As a result, it was revealed that the participants who exercise in
the COVID-19 pandemic have higher levels of psychological resilience than those who do not exercise. In such
cases, studies are needed to raise public awareness about the benefits of exercising
The role of throughput accounting in performance measuring: a case study
Get PDFSon yıllarda rekabetin yoğunlaşması yeni üretim sistemlerindeki gelişmeler işletmelerde performans ölçümünde süreç
katkı muhasebesini ön planı çıkarmıştır. Süreç katkı muhasebesi, işletmenin performansını verimli ve etkin bir şekilde
ölçerek, darboğazların elimine edilmesine, kaynakların daha etkin kullanılmasına, maliyetlerin azaltılmasına ve kâr
maksimizasyona katkı sağlar. Çalışmanın temel amacı, işletmelerin performans ölçümünde süreç katkı muhasebesinin
rolünün incelenmesidir. Bunun için kamuya ve özel sektöre ait örnek birer işletmede yarı yapılandırılmış mülakat
yöntemi uygulanmıştır. Elde edilen bilgiler karşılaştırılmış ve uygulama sonucunda performans ölçümünde süreç katkı
muhasebesinin olumlu etkisi olduğu görülmüştür.In recent years, the competition has increased in business world to develop new production systems which has led to
the emergence of throughput accounting in performance measurement. Throughput accounting contributes to
measuring business performance efficiently and effectively by eliminating bottlenecks, using resources more
effectively, reducing costs and increasing profits. The purpose of this study is examining the role of throughput
accounting in business performance measurements. For this purpose, a semi-structured interview method was applied
in a case study which belongs to the public and private sector. The obtained data has been compared and as a result
we can say that throughput accounting has positive effects on the performance measurement
Academic procrastination, school attachment, and life satisfaction: a mediation model
No full textThe aim of the current study was to investigate the associations between school
attachment, academic procrastination and life satisfaction and the mediating efect
of academic procrastination. The mediation model was tested with 324 adolescents
[173(53.4%) female, 151(46.6%) male, Mage=17.07, SD=2.28]. School Attachment
Scale, Academic Procrastination Scale, and Satisfaction with Life Scale were flled
out. The results indicated that there were signifcant associations among school
attachment, academic procrastination, and life satisfaction. Mediation analysis
revealed that academic procrastination partially mediated the school attachment-life
satisfaction association. Additionally, school attachment had a signifcant indirect
efect on life satisfaction through academic procrastination. Overall, the results show
that school attachment contributes to a reduction in academic procrastination and an
increase in life satisfaction. In this respect, it can be said that attachment to school
has a therapeutic value for students
Proline-stimulated signaling primarily targets the chlorophyll degradation pathway and photosynthesis associated processes to cope with short-term water deficit in maize
No full textIncreased photosynthetic efficiencies in genotypes with greater proline level and in crops treated with proline under water deficit have been reported in recent years, but the biochemical and molecular mechanisms of this process are still not known. We examined photosystem II (PSII) activity, photosynthetic enzymes, ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco), phosphoenolpyruvate carboxylase (PEPc), rubisco activase (RCA), and chlorophyll metabolic enzymes, magne-sium chelatase (Mg-CHLI), and chlorophyllase (Chlase), which would be the primary targets of exogenous proline to provide photosynthetic protection to plants under PEG-induced short-term water deficit. Two maize genotypes W23/M14 with greater proline content and Şafak with low proline content were hydroponically grown for 21–23 days, and then the seedlings were subjected to water deficit (− 0.75 MPa) induced by PEG6000 for 0, 4, and 8 h. Before the seedlings were exposed to the water deficit, proline (1 mM) was applied to the rooting medium of the Şafak genotype for 2 days. The time course effects of the applications showed that exogenous proline significantly enhanced PSII efficiency, PEPc activity, rubisco activity, and the relative expression levels of PEPc, rubisco large subunit, rubisco small subunit, and RCA genes at 0, 4, and 8 h. The W23/M14 genotype had higher rubisco quantity than the Şafak genotype at all time periods. Proline pre-treatment under the stress-free and PEG conditions reduced the activity of Chlase and the gene expressions of Chlase, while it enhanced Mg-CHLIgene expression at 0, 4, and 8 h. Taken together, the results indicated that the primary target of proline-stimulated signaling in maize seedlings exposed to short-term severe water deficit may be to induce PSII efficiency, activities of carbon dioxide fixation enzymes and chlorophyll metabolism and mitigate chlorophyll degradation
Artificial neural network application for novel 3D printed nonuniform ceramic reflectarray antenna
No full textThe main inconvenience in design process of modern high performance reflec-tarray antennas is that these designs are heavily depended on full-wave electro-magnetic simulation tools, where in most of the cases the design optimizationprocess would be an inefficient or impractical. However, thanks to the recentadvances in computer-aided design and advanced hardware systems, artificialneural networks based modeling of microwave systems has become a popularresearch topic. Herein, design optimization of an alumina-based ceramic sub-strate reflectarray antenna by using multilayer perceptron (MLP) and 3D printingtechnology had been presented. MLP-based model of ceramic reflectarray (CRA)unit element is used as a fast, accurate, and reliable surrogated model for the pre-diction of reflection phase of the incoming EM wave on the CRA unit cell withrespect to the variation of unit elements design parameters, operation frequency,and substrate thickness. The structural design of a reflectarray antenna with non-uniform reflector height operating in Xband has been fabricated for the experi-mental measurement of reflectarray performance using 3D printer technology.The horn feeding based CRA antenna has a measured gain characteristic of22 dBi. The performance of the prototyped CRA antenna is compared with thecounterpart reflectarray antenna designs in the literature.Yildiz Technical University: 2015-07-02-YL0
Resilience, hope, and subjective happiness among the Turkish population: Fear of COVID-19 as a mediator
Get PDFPsychology deals with not only mental disorders but also psychological strengths within
individuals. Psychological strengths will play an important role in struggling with the
global novel coronavirus 2019 (COVID-19) pandemic. The present study tested a model
concerning the relationship between resilience, hope, and subjective happiness using
structural equation modeling to identify the mediating role of fear of COVID-19. A
cross-sectional survey was conducted among a convenience sample of 971 Turkish
individuals (aged 18 to 74 years) from 75 of 81 cities in Turkey. The survey included
the Subjective Happiness Scale, Fear of COVID-19 Scale, Brief Resilience Scale, and the
Dispositional Hope Scale, and data were analyzed using structural equation modeling
(SEM). The SEM demonstrated an association between resilience–hope and subjective
happiness was mediated by fear of COVID-19 (CMIN/df = 2.664, CFI = 0.994, NFI =
0.984, TLI = 0.984, GFI = 0.994, RMSEA = 0.044, SRMR = 0.024, AIC = 81.334,
ECVI = 0.084). Resilience had a direct effect and an indirect effect on subjective happiness
via fear of COVID-19. Hope also had a direct effect and an indirect effect on subjective
happiness via fear of COVID-19. Consequently, in the fight against COVID-19, individuals who are resistant to stress and have a belief that they can find a way to cope can help
prevent the fear of COVID-19 and so enhance good mental health
Bacterial cellulose as reinforcement in paper made from recycled office waste pulp
Get PDFBacterial cellulose, produced during fermentation of Kombucha tea, was investigated relative to its ability to modify the characteristics of pulp from recycled office wastepaper. The produced bacterial cellulose wet films were dispersed and added rates of 5%, 10%, and 15% to the recycled office wastepaper. The Fourier-transform infrared spectroscopy analyses, scanning electron microscopy images and thermogravimetric analysis values were determined in order to characterize the pulp samples. The results of these analyses showed similar changes as the amount of added bacterial cellulose increased, which also meant an increased amount of filler attaching to the fiber matrix. The burst index and tensile index values were protected while the tear index value partially decreased as the amount of added bacterial cellulose increased. The brightness values of the bacterial cellulose reinforced papers did not change after thermal aging, while the changes in the yellowness values were quite limited. Higher water absorption rates, and lower air permeability values were obtained from bacterial cellulose reinforced recycled office wastepaper sheets, which corresponded to the addition of increased bacterial cellulose amounts. Considering the mechanical and physical properties of the reinforced paper, bacterial cellulose represents a promising alternative for the reinforcement of office wastepaper
Dodder taxa in Turkey and their impacts
Get PDFBu çalışmada, bir holoparazitik cins olan Cuscuta cinsinin Türkiye’deki mevcut taksonlarının ve
dağılımlarının belirlenmesi ve bu taksonların çevresel ve sosyoekonomik etkilerinin tespiti
amaçlanmıştır. Bu amaçla Türkiye'de Cuscuta taksonlarını içeren çalışmalardan ve Türkiye’deki
herbaryum kayıtlarından kanıtlar elde edilmiştir. Ayrıca taksonların etki türleri incelenmiş ve bu
taksonların bölgesel dağılımı Türkiye kareleme sistemine göre tespit edilmiştir. Tüm kayıtlar, özellikle
sinonim kullanımı, Uluslararası Bitki Adı Endeksi (IPNI), Global Biyoçeşitlilik Bilgi Servisi (GBIF) ve Bitki
Listesi (PL) dikkate alınarak düzenlenmiştir. Mevcut yeni tespitler ve kayıtlarda yapılan düzenlemeler
dikkate alındığında; Türkiye’de Cuscuta cinsine bağlı 23 taksonunun varlığı tespit edilmiştir. Etki
değerlendirmelerinde, tüm taksonların sahip olduğu “parazitizm” dışında, taksonlara göre değişen,
toplam altı farklı etki tipi belirlenmiştir. Bu etki tipleri sırasıyla; toksik (6 takson), ürün kalitesi (5),
vektör (3) ve birer taksonla yapısal, allelopatik ve etnobotanik etki olarak sıralanmıştır. Türkiye’de
mevcut Cuscuta taksonlarına ait bilgilerin güncellenmesi ve etkilerin tespiti ile elde edilen sonuçlar;
özellikle parazit bitkilerin istila potansiyelleri de dikkate alındığında, taksonların olumsuz etkilerini
azaltmak ve biyolojik çeşitliliği korumak amacıyla gerekli önlem ve kontrol programlarını geliştirmek
için kullanılabilir. Ayrıca Türkiye’de ilk kez tüm etki yönleriyle incelenen Cuscuta taksonlarından elde
edilen bu veriler, farkındalık çalışmaları da dâhil, yapılabilecek yeni çalışmalara yön verilebilir ve
kaynak sağlayabilir