1,423 research outputs found
An artificial neural network application on nuclear charge radii
The artificial neural networks (ANNs) have emerged with successful
applications in nuclear physics as well as in many fields of science in recent
years. In this paper, by using (ANNs), we have constructed a formula for the
nuclear charge radii. Statistical modeling of nuclear charge radii by using
ANNs has been seen as to be successful. Also, the charge radii, binding
energies and two-neutron separation energies of Sn isotopes have been
calculated by implementing of the new formula in Hartree-Fock-Bogoliubov (HFB)
calculations. The results of the study shows that the new formula is useful for
describing nuclear charge radii.Comment: 7 pages, 3 figure
THE AIR BORNE PARTICULATE MATTER POLLUTION IN İZMİR
zmir havasındaki partikül madde konsantrasyonları (PM2,5 ve PM10), şehir merkezinde (Yeşildere semti) ve yarı-kırsal özellikteki Dokuz Eylül Üniversitesi Tınaztepe Yerleşkesi'nde eş zamanlı olarak bir yıl boyunca ölçülmüştür. Ölçüm dönemi Haziran 2004 ve Mayıs 2005 tarihleri arasıdır. PM2,5 ve PM10 ortalama konsantrasyonları Tınaztepe'de sırasıyla 24,1 ± 12,2 ve 46,9 ± 20,1 µg m-3, Yeşildere'de 64,4 ± 38,5 ve 80,0 ± 30,2 µg m-3, olarak ölçülmüştür. Her iki partikül madde fraksiyonunda yaz konsantrasyonları Tınaztepe'de kış değerlerinden yüksekken, Yeşildere'de tam tersi olmuştur. Partikül madde konsantrasyonlarının rüzgar yönü, hızı, yağış gibi meteorolojik değişkenlerle ilişkisi irdelenmiş ve bu etmenlerin etkisinin önemli boyutlarda olduğu belirlenmiştir. The ambient air concentrations of particulate matter's fractions (PM2.5 and PM10) were determined concurrently at suburban and urban sites in Izmir, Turkey. The sampling season was between June 2004 and May 2005. The mean concentrations of PM2.5 and PM10 were 24.2 ± 12.2 and 46.9 ± 20.1 µg m-3 at the suburban site and 64.4 ± 38.5 and 80.0 ± 30.2 µg m- 3 at the urban site, respectively. The mean summer concentrations of two fractions were higher than winter ones at the suburban site; on the contrary, the concentrations at the urban site in winter were higher than in summer. The relationships between meteorological parameters such as wind direction, wind velocity and precipitation and the PM concentrations were evaluated. It was obtained that the PM concentrations were notably influenced by these parameters. It was also seen that PM2.5/PM10 ratio was affected by the same parameters; and the temporal variation of PM2.5/PM10 ratio was significant, too. The measured PM10 concentrations were compared to data obtained from four online stations located in the city. The results indicated that the spatial variation of PM10 at the different sites of the city was significant
AA 2024 Levhanın Artışlı Şekillendirilebilirliğinin Üç Boyutlu Lazer Tarama Metoduyla İncelenmesi
Bu çalışmada, günümüzde sac metal şekillendirme sektöründe giderek artan ve çeşitlilik gösteren az sayıdaki talepleri ekonomik açıdan ucuz, zaman açısından da kısa sürede gerçekleştiren artışlı şekillendirme yönteminin değişik parametrelerdeki davranışları incelenmiştir. Çalışmada, artışlı şekillendirme yönteminin çeşitlerinden tek noktalı artışlı şekillendirme yöntemi kullanılmıştır. Malzeme olarak ise 1 mm kalınlığındaki AA 2024-T3 levhalar tercih edilmiştir. Referans bir geometri belirlenip takım yolları, dikey ilerlemeler ve yağlama için kullanılan yağlar değiştirilerek şekillendirmeler yapılmıştır. Takım devri, takım çapı ve yatay ilerleme değerleri ise çalışma boyunca sabit tutulmuştur. Şekillendirmeler sonrasında elde edilen parçaların geometrik doğruluklarını yüksek hassasiyet değerleri çerçevesinde inceleyebilmek için üç boyutlu lazer tarama yöntemi kullanılmıştır
Evaluation of socio-demographic factors and attempted suicides in the elderly
Introduction: The aim of this study is to reveal the socio-demographic and certain clinical characteristics of elderly patients admitted to the emergency department after a suicide attempt.Methods: This is a cross-sectional study. The universe of the study consisted of 96 patients aged 60 and over who were admitted to emergency department of Izmir Dokuz Eylul University Hospital between 2015-2019 due to a suicide attempt. Information for the study was obtained by retrospectively scanning the files of the patients.Results: Mean age of the 96 patients included in the study was 68.22 ± 9.45 years. The most common suicide method among the patients was drug overdose (n: 59, 61.45%). It was found that 45.05% of the patients who attempted suicide had a known psychiatric diagnosis (n:41). The suicide rate of women (n:42, 43.75%) who were primary school graduates (p=0.026), had a known psychiatric illness (p=0.001), continuously used drugs (p=0.002) and used antidepressants (p lt;0.001) was significantly higher compared to men (n:54, 56.25%).Conclusion: Being a primary school graduate, having a psychiatric illness, and using antidepressants increase suicide rates in women. It was suggested that this group of patients with suicidal tendencies should be treated with more care in emergency department
Spatial forecasting of dissolved oxygen concentration in the Eastern Black Sea Basin, Turkey
The aim of this study was to model, as well as monitor and assess the surface water quality in the Eastern Black Sea (EBS) Basin stream, Turkey. The water-quality indicators monitored monthly for the seven streams were water temperature (WT), pH, total dissolved solids (TDS), and electrical conductivity (EC), as well as luminescent dissolved oxygen (LDO) concentration and saturation. Based on an 18-month data monitoring, the surface water quality variation was spatially and temporally evaluated with reference to the Turkish Surface Water Quality Regulation. First, the teaching learning based optimization (TLBO) algorithm and conventional regression analysis (CRA) were applied to three different regression forms, i.e., exponential, power, and linear functions, to predict LDO concentrations. Then, the multivariate adaptive regression splines (MARS) method was employed and three performance measures, namely, mean absolute error (MAE), root means square error (RMSE), and Nash Sutcliffe coefficient of efficiency (NSCE) were used to evaluate the performances of the MARS, TLBO, and CRA methods. The monitoring results revealed that all streams showed the same trend in that lower WT values in the winter months resulted in higher LDO concentrations, while higher WT values in summer led to lower LDO concentrations. Similarly, autumn, which presented the higher TDS concentrations brought about higher EC values, while spring, which presented the lower TDS concentrations gave rise to lower EC values. It was concluded that the water quality of the streams in the EBS basin was high-quality water in terms of the parameters monitored in situ, of which the LDO concentration varied from 9.13 to 10.12 mg/L in summer and from 12.31 to 13.26 mg/L in winter. When the prediction accuracies of the three models were compared, it was seen that the MARS method provided more successful results than the other methods. The results of the TLBO and the CRA methods were very close to each other. The RMSE, MAE, and NSCE values were 0.2599 mg/L, 0.2125 mg/L, and 0.9645, respectively, for the best MARS model, while these values were 0.4167 mg/L, 0.3068 mg/L, and 0.9086, respectively, for the best TLBO and CRA models. In general, the LDO concentration could be successfully predicted using the MARS method with various input combinations of WT, EC, and pH variables
Studies on the reproductive effects of chronic treatment with agomelatine in the rat
Agomelatine is an antidepressant with a novel mechanism of action. It is a melatonergic agonist for MT1 and MT2 receptors and a serotonin (5-HT2C) receptor antagonist. Agomelatine has been suggested not to have adverse effects on sexual functions. However, the effects of chronic agomelatine administration on reproductive functions have not been sufficiently studied in animal models. We mainly aimed to explore the effects of agomelatine on reproductive functions in the male and female rats. For the experimental studies, Sprague Dawley rats were used. The animals started to receive daily oral agomelatine (10mg/kg) on post-natal day 21. Agomelatine advanced vaginal opening in the female rats whereas it delayed puberty onset in the male rats. Agomelatine treatment significantly decreased intromission frequencies, which indicates a facilitator role of this antidepressant on male sexual behavior. In the forced swimming test (FST) used for assessing antidepressant efficacy, agomelatine induced a significant decrease in duration of immobility, and an increase in the swimming time, respectively, which confirms the antidepressant-like activity of agomelatine. The present findings suggest that agomelatine shows a strong antidepressant effect in the male rats without any adverse influences on sexual behavior, and its effects on pubertal maturation seem to show sex-dependent differences.TÜBiTAK – 113S19
Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an
Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV
Peer reviewe
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