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Development of Upper Euphrates Basin hydro-economic model and hydropower generation optimization
Get PDFHydro-economic optimization models are common in hydropower reservoir modeling to aid system operators and planners. In these models, operations are driven by the economic value and constrained by the availability of water. The objective is to either minimize total costs or maximize total benefits. In this study, a hydro-economic optimization model for the integrated reservoir system of the Upper Euphrate s Basin, with major tributaries providing water flow to the Euphrates River, is introduced. These model the 10 large-scale reservoirs of the basin with a total installed capacity of 3,255 MW. Water management and hydropower decision-making operations are evaluated with a piecewise linear programming algorithm in monthly time steps using a 45-year historical hydrology between 1971 and 2016. The model aims to maximize hydropower revenue over a long-term time horizon with energy prices varying by month. Reservoir storage and turbine release decisions are optimized for multiple hydropower plants connected in serial or parallel. Hydropower generation, revenue, reservoir storage, capacity ratios and generation reliability results are analyzed. Results show that these hydropower plants generate about 9,481 Gigawatt hour (GWh) of energy with an average turbine capacit y use of 36% and obtain a revenue of 620 million $ per year
Efficiency and productivity analysis of Turkish public and private sugar factories: evidence from critic and eatwios methods
Get PDFBu çalışmanın amacı Türkiye’de şeker fabrikalarının (kamu-özel) 2018-2020 döneminde, etkinlik ve verimliliğini ortaya koymaktır. Şeker sanayisinin üretim etkinlik analizi ve toplam faktör verimlilikleri Critic ve Eatwios yöntemleri ile analiz edilmektedir. Elde edilen bulgulara göre; 2018, 2019 ve 2020 yıllarının tümünde en önemli girdi değişkeni geçici işçi sayısı iken, en az öneme sahip olan değişken ise 2018 yılında daimi işçi sayısı, 2019 ve 2020 yıllarında işlenen pancar miktarıdır. Çıktı değişkenlerine ait Critic skorları yıllar itibariyle farklılık göstermektedir. Buna göre tüm yıllarda posa en önemli çıktı değişkeni iken; 2018’de üretilen şeker miktarı, 2019 ve 2020 yıllarında ise melas en az öneme sahip çıktı değişkenleridir. Critic yöntemi ile girdi ve çıktı değişkenlerinin önem düzeylerinin belirlenmesinin ardından Eatwios yöntemiyle firmaların verimlilik düzeyleri hesaplanmıştır. Elde edilen bulgulara göre; tüm yıllarda Ö6 kodlu şeker fabrikası en verimli firma iken, Ereğli şeker fabrikası ikinci sırada yer almaktadır. Verimlilik düzeyi en düşük firma ise Erciş şeker fabrikasıdır. Yıllara göre verimlilik düzeyleri değerlendirildiğinde; 2018, 2019 ve 2020 yıllarında Ö6 kodlu şeker fabrikası en verimli firma iken, ikinci sırada 2018 ve 2020 yılında Ereğli şeker fabrikası, 2019 yılında ise Ilgın şeker fabrikası yer almaktadır.The purpose of this study is to exhibit the efficiency and productivity of the both publicly and privately owned sugar factories in Turkey between the years 2018-2020. The production efficiency of the sugar industry and its total factor productivity are analyzed via the Critic and Eatwios methods. The results obtained show that while the most significant input variable is the number of temporary workers for all years spanned, the factors with the least explanatory power are the number of permanent workers for 2018 and the amount of beet processed for the remaining years. The CRITIC scores of output variables also vary within time, and while pulp remains the most significant variable in the model, the amount of sugar produced and molasses are found to have the least significant explanatory power for the first and the remaining years, respectively. Following the determination of the levels of significance of variables via the CRITIC technique, the efficiency levels of companies are calculated by using EATWIOS, where it is put forward that while the factory coded O6 ranks the first among the sample for all years spanned, Ereğli ranks second, and the company with the lowest productivity level is Erciş Sugar Factory. When this analysis is partitioned vis-a-vis their time series trends, it is found out that while Ereğli ranks second in 2018 and 2020, Ilgın is the runner-up to O6 in the year 2019
High or mid-flow oxygen therapy for primary headache disorders: A randomized controlled study
No full textHeadache is one of the most common causes of emergency department (ED) visits. High-flow oxygen therapy is becoming more attractive as a treatment option because it is safe, effective, and cheap. We aimed to compare the effectiveness of high and medium-flow oxygen therapies with placebo for treating primary headache disorders among middle-aged patients. Methods: This prospective, double-blind, placebo-controlled, crossover designed, randomized study was conducted at a regional tertiary hospital's ED. Patients who were treated for primary headache disorder in the ED were evaluated at the time of diagnosis and subsequently included in the study upon their next ED visit. Four different treatment methods were administered; 1) high-flow oxygen (15 L/min oxygen), 2) medium-flow oxygen (8 L/min oxygen), 3) high-flow room air as placebo (15 L/min room air), 4) medium-flow room air as placebo (8 L/min room air). All four treatment methods were administered to all patients included in the study, at four separate ED visits. Patients' data, including demographics, medical history, additional complaints, Visual Analogue Scale (VAS) score, and physical examination findings were recorded by the treating physician. Results: One hundred and four patients with a mean age of 35.14 ± 9.1 years, were included in the study. Patients who received oxygen therapy had a significantly lower VAS score at all control points (15, 30, and 60 min) when compared with placebo (p 0.05). It was determined that patients who received placebo therapy were more likely to revisit ED (p 0.05) and the 30th-minute analgesia requirement (p > 0.05). Pain duration was significantly less in patients who received oxygen therapy (p < 0.05). Patients who received high-flow oxygen therapy spent less time in the ED (p < 0.001). Conclusion: Oxygen therapy could be a beneficial treatment option for middle-aged patients with primary headache disorders. Based on the results obtained from high and mid-flow oxygen therapies, it may be more appropriate to begin treatment with mid-flow oxygen
Hybrinomials Related to Hyper-Fibonacci and Hyper-Lucas Numbers
Get PDFybrid number system is a generalization of complex, hyperbolic and dual numbers. Hybrid numbers and hybrid polynomials have been the subject of much research in recent years. In this paper, hybrinomials related to hyper-Fibonacci and hyper-Lucas numbers are defined. Then some algebraic properties of newly defined hybrinomials are examined such as the recurrence relations and summation formulas. Also, the relation between hybrinomials related to hyper-Fibonacci and hyper-Lucas numbers is given. Additionally, hybrid hyper-Fibonacci and hybrid hyper-Lucas numbers are defined by using the hybrinomials related to hyper-Fibonacci and hyper-Lucas numbers
Pd@MgAl LDH/2-ThCA: A sustainable, active and recyclable nanocatalyst system for the rapid and efficient catalytic reduction of organic pollutants
No full textCatalytic reduction of toxic pollutants such as nitroaromatics and organic dyes found in water/wastewater by heterogeneous nano-structured metallic catalysts is a promising method for wastewater treatment. The need for effective and reusable catalyst systems is recently increasing due to the soaring water pollution. For this purpose, in this study, a newly Pd@MgAl LDH/2-ThCA catalyst system was successfully developed by depositing palladium nanoparticles onto a modified MgAl LDH support, characterized and then used to eliminate these contaminants in the presence of NaBH4. Catalytic applications indicated that Pd@MgAl LDH/2-ThCA catalyst efficiently reduced 2-nitroaniline (2-NA), 4-nitrophenole (4-NP), 4-nitroaniline (4-NA), and 4-nitro-o-phenylenediamine (4-NPDA) with rate constants of 0.011 s−1, 0.0075 s−1, 0.017 s−1, and 0.02 s−1, respectively. Additionally, Pd@MgAl LDH/2-ThCA successfully degraded methyl orange (MO) and rhodamine B (RhB) with rate constants of 0.019 s−1 and 0.015 s−1, respectively. Furthermore, it was found that methylene blue (MB) was immediately degraded by Pd@MgAl LDH/2-ThCA. Reusability tests revealed that Pd@MgAl LDH/2-ThCA maintained its activity/stability after the 5 successive cycles, verifying its practical application potential. This paper reveals that Pd@MgAl LDH/2-ThCA is an effective, sustainable, and alternative catalyst system for the treatment of toxic environmental pollutants
Investigation of ischemia-modified albumin and thiol/disulfide homeostasis for the determination of oxidative stress in sheep with toxoplasmosis
No full textIn this study, the aim was to investigate the thiol/disulfide homeostasis (TDH) parameters and ischemia-modified albumin (IMA) (ABSU) levels to determine oxidative stress in sheep with toxoplasmosis. Twenty-four Morkaraman sheep used in this study were allocated into two groups, one control group and one experimental group. Each group included 12 sheep. Blood samples were taken from all sheep only once and blood serum levels of albumin (ALB) (g/L), IMA (ABSU), native thiol (NT) (μmol/L), total thiol (TT) (μmol/L), disulfide (Ds) (μmol/L), Ds/NT, Ds/TT, NT/TT were investigated. Our results showed that the IMA (ABSU) levels of toxoplasma group were significantly higher than control group (p < 0.05). However, NT (μmol/L) and TT (μmol/L) level of toxoplasma group were significantly lower than the control group (p < 0.05). While the oxidant and antioxidant parameters were positively correlated within themselves, a negative correlation was determined between the antioxidant and oxidant parameters. In the Receiver Operating Characteristic (ROC) analysis, the area under the ROC curve (AUC), sensitivity, cut off and specificity values were determined for IMA (ABSU) values. These values were determined as 0.812, 1.24, 91.7% and 75.0%, respectively. For TT (μmol/L), these values were obtained as 0.750, 330.55, 75.0% and 66.7%. It was concluded that oxidative stress is intensely formed in sheep with toxoplasmosis, thiol-disulphide homestasis markers, and IMA (ABSU) are valuable markers in determining oxidative stress in toxoplasmosis
Efficient purification of aqueous solutions contaminated with sulfadiazine by coupling electro-Fenton/ultrasound process: optimization, DFT calculation, and innovative study of human health risk assessment
No full textIn the current work, the hybrid process potential of ultrasound (US) and electro-Fenton (EF), named sono-electro-Fenton (SEF), was fully investigated for sulfadiazine (SDZ) degradation. The decontamination in the integration approach was revealed to be greater than in individual procedures, i.e., EF process (roughly 66%) and US process (roughly 15%). The key operating process factors (i.e., applied voltage, H2O2 content, pH, initial concentration of SDZ, and reaction time) affecting SDZ removal were evaluated and optimized using Box-Behnken Design (BBD). In addition, an adaptive neuro-fuzzy inference system (ANFIS) as an efficient predictive model was applied to forecast the decontamination efficiency of SDZ through the SEF process based on the same findings produced from BBD. The results revealed that the predictability of SDZ elimination by the ANFIS and BBD approaches exhibited an excellent agreement (a greater R 2 of 0.99%) among the both models. Density functional theory was also employed to forecast the plausible decomposition elucidation by the bond-breaking mechanism of organic substances. Plus, the main side products of SDZ degradation during the SEF process were tracked. Eventually, the non-carcinogenic risk assessment of different samples of natural water containing SDZ that was treated by adopting US, EF, and SEF processes was examined for the first time. The findings indicated that the non-carcinogenic risk (HQ) values of all the purified water sources were computed in the permissible range
The Role of Matrix Metalloproteinase As Biomarkers For Neural Tube Defect
Get PDFNeural Tube Defect (NTD) is one of the most common congenital malformations. It is crucial to determine the prognostic, predictive, or therapeutic genetic factors for prevent ing NTD. The formation of the extracellular matrix (ECM) plays an essential role in migrating neural crest cells. Matrix metalloproteinases (MMPs) play a significant role in cell migration in ECM organization. The role of expressions and activation of MMP in NTD is unknown. This study aimed to investigate the roles of MMP-1, -2, and 9 gene expressions as biomarkers for NTD. Peripheral blood samples and NTD tissues were collected from 40 newborn babies diagnosed with NTD, which were also divided into subgroups based on pathology, and peripheral blood samples from only 20 healthy babies were taken for control. After total RNA isolation from blood and tissues, MMP -1, -2, -9 gene expressions were analyzed by Quantitative Real-Time PCR (RT-PCR). There was no difference between the control group and the NTD group in terms of MMP expressions in blood samples (p>0.05). A statistically significantly higher MMP-1 expression was found in Meningocele and Myeloschisis than in Encephalocele (p=0.014). A significant difference was found between the tissue and blood samples of the Meningomyelocele patient group regarding MMP-9 expression (p=0.019). There was no significant relationship between Ca2+, B12, and Folate levels, NTD, and MMP genes expressions (p>0.05). Even though MMP genes were not different between control and NTD groups, they were found to vary between different subgroups and can serve as biomarkers
Kamu yönetimi tezsiz yüksek lisans programı öğrencilerine göre öğrenimde yaşanan sorunlar ve öneriler
Get PDFStudents of the non-thesis master's program in public administration experience various problems in their education. They are waiting for a solution to their problems. The question of what the problems are and how to solve them is the subject of this research. The study aimed to identify program problems and solutions based on the perceptions of students enrolled in a non-thesis master’s program of public administration where the research was conducted. The study was conducted descriptively using the qualitative research method of case design descriptive analysis, and a single case design. The non-probabilistic sampling method of purposeful sampling was used. The participant group was made up of public administration students enrolled in the non- thesis master’s program. Data were gathered through observation, interviews, and document analysis. Semi- structured interview questions were used to collect data. The research data were coded in the Maxqda 2022 program, and categories based on codes and themes based on categories were identified. According to the participants, the problems experienced in education in the non-thesis master’s program arise from two main factors. One of them is the problems arising from the students and the other is the problems arising from the applications in the non-thesis master's proKamu yönetimi tezsiz yüksek lisans programı öğrencileri eğitimlerinde çeşitli sorunlar yaşamaktadır. Sorunlarına çözüm beklemetedirler. Sorunların neler olduğu ve nasıl çözüleceği sorusu bu araştırmanın konusudur. Araştırma, araştırmanın yürütüldüğü kamu yönetimi anabilim dalı tezsiz yüksek lisans programındaki öğrencilerin görüşleri doğrultusunda programda yaşanan sorunları ve çözümü için önerileri belirlemeyi amaçlamıştır. Araştırma, nitel araştırma yöntemi, olgu bilim, tekli durum deseniyle betimsel olarak yürütülmüştür. Olasılıklı olmayan örnekleme türlerinden biri olan amaçlı örneklem yöntemi seçilmiştir. Katılımcı grubunu tezsiz yüksek lisans programına kayıtlı kamu yönetimi anabilim dalı öğrencilerinden belirlenen öğrenciler oluşturmuştur. Veri toplama aracı olarak gözlem ve görüşmeyle doküman incelemesinden yararlanılmıştır. Yarı yapılandırılmış görüşme sorularıyla veriler toplanmıştır. Araştırmada elde edilen veriler Maxqda 2022 programında kodlanmış, kodlara dayalı kategorilere ve kategorilere dayalı temalara ulaşılmıştır. Katılımcılara göre bölümdeki öğrenimde yaşanan sorunlar iki temel etkenden kaynaklanmaktadır. Bunlardan biri öğrencilerin kendilerinden kaynaklanan sorunlar ve diğeri ise tezsiz yüksek lisans programındaki uygulamalardan kaynaklanan sorunlardır
Understanding the effects of chitosan, chia mucilage, levan based composite coatings on the shelf life of sweet cherry
Get PDFSweet cherry (Prunus avium L.) fruits are prone to quality and quantity loss in shelf-life conditions and cold storage due to their short post-harvest life. Until now efforts have been made to extend the shelf life of the sweet cherry. However, an efficient and commercially scalable process remains elusive. To contribute to this challenge, here in this study, biobased composite coatings consisting of chitosan, mucilage, and levan, were applied on sweet cherry fruits and tested for postharvest parameters in both market and cold storage conditions. Results demonstrated that the shelf life of sweet cherries can be extended until the 30th day while retaining important post-harvest properties like decreased weight loss, fungal deterioration, increased stem removal force, total flavonoid, L-ascorbic acid, and oxalic acid. Given the cost-effectiveness of the polymers used, the findings of this study indicate the feasibility of extending the shelf-life of sweet cherries on a larger scale