İplik Bobini Kurutulması Prosesinde Sıcaklık Alanının Sonlu Farklar Yöntemi İle Belirlenmesinde Bazı Faktörlerin Çözüm Hassaslığına Etkisi

In this study, a mathematical model for the drying process of dyed wool yarn bobbins by passing hot air through them has been presented. The presented mathematical model reduced the drying problem to a nonlinear, nonstationary heat convection problem including the convective effect caused by forced convection, together with the effective thermophysical properties of the wool yarn bobbins. The finite difference method was used for solving the mathematical model.Bu çalışmada, boyanmış yün iplik bobinlerinin içerisinden basınçlı sıcak hava geçirilerek kurutulması işlemi için bir matematiksel model ortaya konmuştur. Sunulan matematiksel model, kurutma problemini, içerisinde yün iplik bobinin efektif termofiziksel özellikleriyle birlikte, zorlanmış taşınım etkisinden kaynaklanan konvektif terimi barındıran nonlineer, nonstasionar bir ısı taşınımı problemine indirgemiştir. Matematiksel modelin çözümü için sonlu farklar metodu kullanılmıştır. Bu yöntemde uygulanan algoritmadaki uzay ve zaman adımlarının ve nonlineerliğin (ke(T), Cve(T)) sıcaklık alanına etkisi incelenmiştir

Antimicrobial and antioxidant activities of Momordica charantia from Turkey

Momordica charantia L. has long been regarded as a food and medicinal plant. Although it is not a native plant in Turkey, it is frequently used in folk medicine, especially in west and southwest parts of Anatolia. In the present study, unripe/ripe seed and fruit ethanol extracts of M. charantia from Turkey were screened for their potential antimicrobial and antioxidant activities. The antimicrobial activities of the extract were determined against four gram positive bacteria, seven gram negative bacteria, and one yeast with disc diffusion and microdilution broth methods. The extracts were also tested in vitro against four different fish pathogens. The unripe fruit extract was the most active against the tested microorganisms in the study with higher inhibition zones and lower minimal bactericidal or fungicidal activities (MBC or MFC) than the other extracts. Antioxidant capacity of the extracts was investigated by different assay, namely, total antioxidant activity, free radical scavenging activity (DPPH assay), iron (III) and cupric ion reduction assay. The total phenolic content was only determined from ripe fruit and seed extracts as 23.45 and 9.36 mg GAE/g, respectively. The results show that the ripe fruit extract has the strongest antioxidant capacity compared with other extracts. The findings indicate the potential use of unripe fruit and ripe fruit extracts as biopreservatives as they demonstrated high antimicrobial and antioxidant activities, respectively.Keywords: Fruit, seed, ethanol extract, food borne and clinical pathogens, fish pathogensAfrican Journal of Biotechnology, Vol. 12(13), pp. 1548-155

Channel Estimation Using RIDNet Assisted OMP for Hybrid-field THz Massive MIMO Systems

The terahertz (THz) band radio access with larger available bandwidth is anticipated to provide higher capacities for next-generation wireless communication systems. However, higher path loss at THz frequencies significantly limits the wireless communication range. Massive multiple-input multiple-output (mMIMO) is an attractive technology to increase the Rayleigh distance by generating higher gain beams using low wavelength and highly directive antenna array aperture. In addition, both far-field and near-field components of the antenna system should be considered for modelling THz electromagnetic propagation, where the channel estimation for this environment becomes a challenging task. This paper proposes a novel channel estimation method using a recursive information distillation network (RIDNet) together with orthogonal matching pursuit (OMP) for hybrid-field THz mMIMO channels, including both far-field and near-field components. The simulation experiments are performed using the ray-tracing tool. The results indicate that the proposed RIDNet-based method consistently provides lower channel estimation errors compared to the conventional OMP algorithm for all signal-to-noise ratio (SNR) regimes, and the performance gap becomes higher at low SNR regimes. Furthermore, the results imply that the same error performance of the OMP can be achieved by the RIDNet-based method using a lower number of RF chains and pilot symbols.Comment: Accepted to publication in ICC-202

Investigation of the effect of drying air temperature on drying time by numerical method for textile bobbins

22nd National Conference on Thermodynamics with International Participation, NACOT 2019 -- 23 May 2019 through 24 May 2019 -- -- 152413Drying of the yarn bobbins in the textile sector is a very important stage among the textile finishing processes. Because this process takes a lot of time and causes a large amount of energy consumption. In this study, drying times for different drying air inlet temperatures at a constant drying air pressure were determined with the help of mathematical model for textile bobbin drying process. Finite difference method was used in mathematical model solution and the effect of different space and time steps were taken into consideration during the solution. © Published under licence by IOP Publishing Ltd

Antioxidative, antimicrobial and cytotoxic properties of Isatis floribunda Boiss. ex Bornm. extracts

The Isatis species has antibacterial, anticancer and antiviral properties and these important endemic plants grow widely in various parts of Anatolian-Turkey. In the present study, the antioxidant activities of Isatis floribunda Boiss. ex Bornm. flower and root extracts were determined with total antioxidant activity, free radical scavenging activity, ferric ion reducing power, and cupric ion reducing antioxidant capacity assay. The total phenolic compounds and flavonoids were also examined for the extracts. The antimicrobial activities of the extracts were investigated by using the disc diffusion and microdilution-broth methods against human and fish pathogen microorganisms. The phenolic composition of I. floribunda root methanolic extract was analyzed by high performance liquid chromatography (HPLC). The major component in the extract was cholorogenic acid (1980.20 μg/g). The cytotoxic effect of the methanolic root extract was also tested on human breast cell (MCF12A). The results showed that I. floribunda could be used as a natural source in the food and feed industry and clinical and food chemistry, and that the antimicrobial agents could be used against human and fish pathogens

Practical Implementation of Evidence-Based Dentistry Into Daily Dental Practice Through a Short Time Dependent Searching Method

INTRODUCTION:Despite the fact that the benefits of implementation of Evidence-Based Dentistry (EBD) into clinical practice is increasingly being highlighted, there are still clear limitations in its implementation into daily dental practice. One potentially important barrier to effective implementation into practice is the perception of EBD as a time-consuming process. The aim of the present study is to increase the familiarity of dental practitioners with the benefits of different time-dependent 'practical' search strategies important to EBD using a clinical question from the field of dental implantology as an example. MATERIALS AND METHODS:The PICO (population, intervention, comparison, outcome) question used in this study was: "In young adults with anterior single-tooth implant what is the effect of immediate or delayed loading on success?" A bibliographic search according to the Haynes 5S pyramid, together with 3 different time-dependent strategies (5-min, 30-min and more than 60-min), were applied. RESULTS:Both the Haynes 5S Pyramid and time-dependent search strategies revealed promising results for enhancing decision-making for determining the feasibility of immediate or conventional loading of anterior single dental implants. Results clearly showed that selection of the loading protocol would be case (patient)-specific and also indicated high primary implant stability and bone quality as the most important prerequisites for a successful immediate/early loading. From among the 3 different time-dependent strategies (5 min, 30 min and more than 60 min), the 60+ min search results were quite comparable with the Haynes pyramid search results. CONCLUSION:It is likely that the different time-dependent search strategies may have the potential to support the clinical decision making process and may improve the implementation of EBD into daily dental practice. Increased time spent searching naturally seems to increase the extent of this support. However, even with short time-dependent searches, busy dental clinicians may get an improved idea/opinion regarding a clinical question

Big Data Types : Internally Parallel in an Actor Language

Around year 2005 the hardware industry hit a power wall. It was no longer possible to drastically increasing computer performance through decreasing the transistors' size or increasing the clock-speed of the CPU. To ensure future development multi-core processors became the way to go. The Programming Languages Group at Uppsala University is developing a programming language called Encore that is developed to be scalable to future machines with a few hundred or even thousand processor cores. This thesis reports on the design and implementation of Big data types. Big data types are locally distributed data structures that allow internal parallelism in the actor model by using several actors in their implementations. Thus, rather than serializing all interaction these data structures are potentially as parallel as the number of actors used to construct them. The goal of Big data types is to provide a tool that makes it easier for an Encore programmer to create parallel and concurrent programs. As part of our evaluation, we have implemented a Mapreduce framework which showcase how of Big data types could be used in a more complex program

DETERMINATION OF TEMPERATURE FIELD FOR DRYING PROCESS OF YARN BOBBINS USING FINITE DIFFERENCE METHOD

Bu çalışmada boyanmış yün iplik bobinlerinin içerisinden basınçlı sıcak hava geçirilerek kurutulması işlemi için bir matematiksel model ortaya konmuştur. Sunulan matematiksel model, kurutma problemini, içerisinde yün iplik bobinin efektif termofiziksel özellikleriyle birlikte, zorlanmış taşınım etkisinden kaynaklanan konvektif terimi barındıran nonlineer bir ısı taşınımı problemine indirgemiştir. Matematiksel modelin çözümü için sonlu farklar metodu kullanılmıştır. Çalışmada elde edilen matematiksel model sonuçları deneysel sonuçlarla karşılaştırılmıştır. Çalışmada ayrıca sonlu farklar çözümünün içerdiği zaman ve uzay adımlarının, ortaya konan matematiksel modelin çözümüne etkisi de incelenmiştir. Farklı zaman ve uzay adımları için elde edilen sonuçlar incelendiğinde, zaman ve uzay adımlarının kurutma süresi boyunca bobinin her noktasında sabit aralıklarla seçilmesinin hassas ve doğru sonuçlar vermediği görülmüştür. Kurutma işlemi sırasında iplik bobini içerisinde faz dönüşümünün daha yoğun gerçekleştiği zaman aralıklarında zaman adımının büyük seçilmesi ve faz dönüşümünün hızlı olduğu sıcaklık ölçüm noktalarında ise uzay adımının düşük seçilmesinin modelin çözümünde daha hassas ve doğru sonuçlar verdiği görülmüştür.In this study, a mathematical model for the drying of yarn bobbins through forced hot air was presented. The mathematical model presented reduces the drying problem to a nonlinear heat convection problem involving the convective term caused by forced convection, together with the effective thermophysical properties of the wool yarn bobbin. The finite difference method is used to solve the model. The mathematical model results obtained in the study were compared with the experimental results. Also in the study, the effect of the time and space step on the model in the solution of the finite difference solution was examined. The model was solved using different time and space steps and the results were compared with the experimental data. When the results obtained for the different time and space steps were examined, it has been found that the selection of the time and space steps at fixed intervals at every point of the bobbin during the drying period is not sensitive and accurate. It is concluded that during the drying process, when the phase conversion is more intense in the yarn bobbin the selection of time step at higher values, and at the temperature measurement points where the phase conversion is fast the selection of space step at lower values gives more sensitive and accurate results in the solution of the model