Koleksiyon/r/gumushane/10001

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Koleksiyondaki öğeler

  • MakaleYalnız künye2018Scopus SJRQ1
    Geochemical and Sr-Nd-Pb isotope characteristics of the Miocene to Pliocene volcanic rocks from the Kandilli (Erzurum) area, Eastern Anatolia (Turkey): Implications for magma evolution in extension-related origin

    Kaygusuz, Abdullah; Aslan, Zafer; Aydınçakır, Emre; Yücel, Cem; Gücer, Mehmet Ali; Şen, Cüneyt

    This paper presents Sr-Nd-Pb isotopic and whole-rock geochemical data of Miocene to Pliocene volcanic rocks in the Eastern Anatolia (Turkey) aiming to unravel their sources and evolutionary history. The wide compositional range of lavas and pyroclastics includes basaltic andesite, basaltic trachyandesite, trachyandesite, andesite and trachydacite. These calc-alkaline volcanics are enriched in large ion lithophile elements and light rare earth elements and depleted in the high field strength elements. Sr-Nd isotope data indicate low values for 87Sr/86Sr(i) (0.70432–0.70464) and high values for 143Nd/144Nd(i) (0.51272–0.51282). Further, these data are within the mantle array of the isotope ratio diagram. The lead (Pb) isotopic compositions (206Pb/204Pb(i) = 18.33 to 18.62, 207Pb/204Pb(i) = 15.51 to 15.60, 208Pb/204Pb(i) = 38.10 to 38.45) reveals the presence of an enriched source. The main petrological processes involved fractional crystallization and the mixing of at least two fractionated magmas having same source characteristics. All evidence supports the findings that the Kandilli volcanic rocks were derived from a partial melting of the both spinel and garnet bearing subcontinental lithospheric mantle, which had been previously metasomatized by mostly fluids derived from subducted slab during the collisional and post-collisional extension-related geodynamic setting in the Eastern Anatolia region of Turkey.

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  • BildiriYalnız künye2016
    A third order of accuracy difference scheme for Dirichlet type overdermined problem with mixed boundary value conditions

    Ashyralyyev, Charyyar; Dedeturk, Mutlu

    Approximation of Dirichlet type overdetermined multidimensional elliptic problem with Dirichlet-Neumann boundary conditions are discussed. A third order of accuracy difference scheme for its approximate solution is proposed. The stability, almost coercive stability and coercive stability inequalities for the solution of constructed difference scheme are established. Test example for a two-dimensional elliptic problem is presented.

  • MakaleYalnız künye2019Scopus SJRQ3
    Radioactivity measurements in spas of central and Eastern Black Sea region, Turkey

    Duran, S.U.; Küçükömeroğlu, B.; Çevik, U.; Çelik, N.; Taskin, H.; Ersoy, H.

    Background: The aim of this study is to measure the level of radon gas in the thermal springs of the four seasons in the Black Sea Region and to determine the gamma activity levels in the soils around them. Materials and Methods: Indoor radon activity concentrations of four spa facilities, namely Ladik, Havza, Ilıcaköy, and Ayder, were measured using CR-39 passive radon dosimeters and active radon monitoring AlphaGUARD for all four seasons. Radon activity concentrations in the soil in the vicinity of these spa facilities were measured using AlphaGUARD. Radionuclides in the soil samples collected from the spa regions were also determined using gamma-ray spectroscopy. Results: The highest radon value in the air environment in the spa facility was measured in swimming pools. Indoor radon levels in the spa's swimming pool vary within a wide range, (30-2118) Bq·m−3. The average radon gas levels in the soil around the Ayder, Havza, Ladik and Ilıcaköy hot springs were measured as 38±1 kBqm-3, 9±1 kBq m-3, 50±3 kBqm-3, 955±5 kBqm-3, respectively. Conclusion: The annual effective doses due to indoor radon sources changed from 0.6 mSv to 13.4 mSv for workers, and from 1 x10 -4 mSv to 3x10-1 mSv for patients. The annual effective dose equivalents from the soils around the spa were calculated to be between 82-558 µSv y-1. The results were compared with those of other measurements performed in different parts of the world.

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  • MakaleAçık Erişim2017Scopus SJRQ3
    Cytotoxic effect of Laurocerasus officinalis extract on human cancer cell lines; [Laurocerasus officinalis ekstraktının İnsan kanser hücre serileri üzerindeki sitotoksik etkisi]

    Demİr, Selim; Turan, İbrahim; Demİr, Feyza; Ayazoğlu Demİr, Elif; Alıyazicioğlu, Yuksel

    Laurocerasus officinalis Roem. (Prunus laurocerasus L.), also locally known as “karayemis or taflan”, is a popular black summer fruit belonging to the genus Prunus and the family Rosaceae. L. officinalis exhibits numerous biological activities, such as anti-inflammatory, antinociceptive, antioxidant, neuroprotective, and antidiabetic effects. The aim of this study was to determine the total phenolic content and cytotoxic effect of dimethyl sulfoxide extract of L. officinalis (DEL). The total phenolic content and cytotoxic effect of DEL were investigated using the Folin-Ciocalteu method and thiazolyl blue tetrazolium bromide (MTT) assay, respectively. Total phenolic content value was 33.7±0.13 mg gallic acid equivalent per g sample. DEL exhibited selective cytotoxic effects against four human cancer (lung, colon, liver, and cervix) cell lines. The most selective cytotoxic effect of the extract was observed in colon cancer cells (IC50=265.2±8.1 μg/mL) compared to normal fibroblast cells. These data demonstrate that L. officinalis extract exhibits selective cytotoxicity towards some cancer cells. Further studies are now needed to clarify the molecules involved and their mechanisms.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus17WoS21OpenAlex34TR Dizin14
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  • MakaleAçık Erişim2018Scopus SJRQ2
    Sensitivity-Based Model Updating of Building Frames using Modal Test Data

    Altunişik, Ahmet Can; Karahasan, Olguhan Şevket; Genç, Ali Fuat; Okur, Fatih Yesevi; Günaydin, Murat; Adanur, Süleyman

    Model updating is of significant importance in the actual analyses of real structures. The differences between experimental and numerical dynamic characteristics can be minimized by means of this procedure. This procedure can be carried out using two approaches, namely, the manual model updating and the global or local automated model updating. The local model updating is a convenient tool for all kind of structures capable of minimizing the differences mentioned previously nearly to zero and also of identifying the damage locations and monitoring structural integrity. In this way, current realistic behavior of structures can be represented by updated finite element models. This paper describes a Reinforced Concrete (RC) frame model, its ambient vibration testing, finite element modeling and sensitivity-based automated model updating. The RC frame is of ½ geometric scale with two floors and two bays in the longitudinal direction. It was built and then subjected to ambient vibration tests to determine experimentally their dynamic characteristics. Additionally, the finite element computer program ANSYS was used to determine its initial numerical dynamic characteristics. The experimental and numerical results were compared resulting in maximum differences of 38.38% between them. To minimize these differences, the finite element model was updated using the global and local automated approach using a sensitivity-based analyses with some uncertain parameters. The differences were finally reduced to 4.4% and 0.21% by the global and the local automated model updatings, respectively. It is concluded that sensitivity-based automated updating is a very effective procedure to obtain the updated finite element model which can reflect the current behavior of a structure.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus14WoS13OpenAlex13
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  • MakaleAçık Erişim2018Scopus SJRQ3
    Next-generation sequencing of plasmid carrying blaOXA-48 in Klebsiella pneumoniae from Turkey

    Düzgün, Azer Özad; Saral, Ayşegül

    A carbapenem-resistant Klebsiella pneumoniae strain was isolated in Turkey in 2012 and blaNDM-1 and blaOXA-48 genes were observed in this strain. The aim of this study was to investigate transferability of plasmid bearing blaOXA-48 in K. pneumoniae and to use whole-genome sequencing in order to understand the genetic context of plasmid. K. pneumoniae strain was used as donor in conjugation experiments. Antibiotic susceptibility profile of selected transconjugant was determined. Plasmid was isolated from transconjugant colony and was named as pKPT. Complete sequencing of the pKPT was conducted using a next-generation sequencing. Annotation of the contigs was performed using the Geneious R9, followed by finding open reading frames (ORFs) with selected web-based tools. BLAST analysis was performed at the NCBI BLAST server to determine genes showing more than 90% similarity with these ORFs. Results of antibiotic susceptibility test showed that transconjugant colony was resistant to ampicillin/ sulbactam, piperacillin, and piperacillin/tazobactam. The pKPT plasmid had a length of 45,217 bp and an average G + C content of 49%. Blast analysis revealed that pKPT was included in the IncL/M incompatibility group. The pKPT was found to contain blaOXA-48 within Tn1999.2 transposon without any other antibiotic resistance gene.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus3WoS3OpenAlex5
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  • BildiriYalnız künye2017
    Regional and temporal evaluation of earthquake activity in tunceli province of Turkey: Standard normal deviate Z-test

    Öztürk, S.; Sari, M.

    A statistical evaluation of earthquake activity for Tunceli province of Turkey was made by applying standard normal deviate Z-test. For this purpose, regional and temporal changes of the seismicity rate at the beginning of 2017 was analyzed by using ZMAP software.The data set is compiled from Bogaziçi University, Kandilli Observatory and Earthquake Research Institute.There are 5462 events from September 21, 1970 to December 30, 2016 with magnitude larger than and equal to 1.1. Completeness magnitude is estimated as 2.8. Three regions indicating important quiescence anomaly were observed at the beginning of 2017.These anomalies are found centered at (a) 39.24°N-39.51°E (around city center, and between Ovacik and Pülümür), (b) 38.98°N-39.41°E (including Pertek) and (c) 38.96°N-39.78°E (region including Mazgirt).These quiescence anomalies are observed in the recent years and they start approximately at the years of 2012 and 2015.The regions in which seismic quiescence are found may be the possible areas for the future earthquakes and for this reason, special attention should be given to these regions. As an important result, the estimation of seismicity rate changes and detecting the precursory seismic quiescence can be used as an important tool in the assessment of earthquake potential.

  • MakaleYalnız künye2018Scopus SJRQ2
    Investigation of high temperature wear resistance of TiCrAlCN/TiAlN multilayer coatings over M2 steel

    Sukuroglu, E.E.; Baran, O.; Totik, Y.; Efeoglu, I.

    In this study, TiCrAlCN/TiAlN multilayer coatings were deposited on M2 high speed steel substrates by the Closed-Field Unbalanced Magnetron Sputtering system. The chemical composition, microstructure, morphology, mechanical and high temperature wear resistance properties of the coatings were characterized, analyzed and compared to the substrate. The high temperature wear tests were carried out under a load of 2 N at the lap (wear test distance) of 50 m and in dry sliding condition at Room Temperature (RT), 150, 300, 450, and 600 °C on atmospheric conditions. It has been found that the TiCrAlCN/TiAlN multilayer coatings have a higher wear resistance than the M2 substrate. The stable friction behavior and low friction tendency was determined at 600 °C. When the test temperature increased, the wear rates decreased. Narrow and smooth wear tracks and also the lowest wear rate were obtained at 600 °C.

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  • MakaleAçık Erişim2017Scopus SJRQ3
    Effect of the Simultaneous Variation in Blade Root Chord Length and Blade Taper on Helicopter Flight Control Effort

    Oktay, Tugrul; Sal, Firat

    In this study, the effect of simultaneous variation in blade root chord length and blade taper on the control effort of helicopter flight control system (i.e., FCS) of a helicopter is investigated. Therefore, helicopter models (i.e., complex, control-oriented, and physics-based models) including the main physics and essential dynamics are used. The effect of simultaneous variation in the blade root chord length and blade taper (i.e., in both chordwise and lengthwise directions dependently) on the control effort of an FCS of a helicopter and also on the closed-loop responses is studied. Comparisons in terms of the control effort and peak values with and without variations in the blade root chord and blade taper changes are carried out. For helicopter FCS variance-constrained controllers, specific output variance-constrained controllers are beneficial.

    AtıfScopus13WoS11OpenAlex16
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  • MakaleYalnız künye2018Scopus SJRQ1
    The effect of reiki on pain: A meta-analysis

    Demir Doğan, Melike

    Objective: Pain is one of the most common symptoms and may lead to important psychological, mental, and physiological problems in individuals. According to data by The Center for Reiki Research, Reiki is an effective approach to decrease the levels of pain, depression, and anxiety. Therefore, the aim of this meta-analysis was to investigate the effect of Reiki on pain level. Methods: Randomized controlled clinical trials in databases of Pubmed, ISI Web of Sciences, and Google Scholar were investigated. 4 randomized controlled studies involving 212 participants were included in the meta-analysis. Results: The result obtained after the final Reiki application was evaluated in VAS pain score. When Reiki (n = 104) group was compared with control group (n = 108), standardized mean difference was observed to be −0.927 (95% CI: −1.867 to 0.0124). Reiki was observed to cause a statistically significant decrease in VAS score. Conclusion: Consequently, this meta-analysis revealed that Reiki was an effective approach in relieving the pain.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus63WoS56OpenAlex93
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  • MakaleAçık Erişim2017Scopus SJRQ3
    Diversity and ecology of benthic diatoms in karagöl lake in karagöl-Sahara national park (Şavşat, Artvin, Turkey)

    Akar, Bülent; Şahin, Bülent

    The main goal of this study is to determine the composition, diversity and ecology of benthic diatoms in Karagöl Lake in Karagöl-Sahara National Park. Monthly sampling (from sediments, stones and aquatic plants in littoral zone of the lake) taken in three consecutive years revealed 57 diatom taxa with Gomphonema and Pinnularia being the most abundant species while other genera are represented with three or fewer species. Lindavia ocellata was the most dominant taxon in the samplings examined throughout the whole study. The values of diversity and evenness indices are high during the spring and early summer. Based on cluster analysis for monthly samples of epipelic diatom, there are two different groups at the lowest similarity level. The associations between August 2010 and September 2010 months are the most significant with 86.02%. The organism number of epipelic diatoms showed positive correlation (P<0.01) with dissolved oxygen, while negative correlation (P<0.05) with temperature. Detailed floristic and ecological examination of the benthic diatom communities has not been carried out before this study in this lake. Therefore, this study is the first to our knowledge towards revealing aquatic benthic diatom biodiversity of Karagöl-Sahara National Park and provides basis for future investigations.

    AtıfScopus7WoS9OpenAlex4
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  • BildiriYalnız künye2018
    A third order of accuracy difference scheme for Bitsadze-Samarskii type elliptic overdetermined multi-point problem

    Ashyralyyev, Charyyar; Akyüz, Gulzlpa

    In this study, a third order of accuracy difference scheme for Bitsadze-Samarskii type multi-point elliptic overdetermined problem is studied. For solution of constructed difference problem stability, almost coercive stability and coercive stability estimates are established. The theoretical statements for the solution of this difference problem are supported by numerical results in test example by using Matlab.

  • MakaleAçık Erişim2019Scopus SJRQ3
    Investigation of certain nutritional properties of noodle enriched with raw flaxseed

    Yuksel, F.

    In this study, traditional homemade noodles were enriched with raw flaxseed and some nutritional properties such as resistant starch (RS), total starch, total dietary fibre (TDF), estimated glycaemic index (eGI) and major mineral composition of final products were investigated. Flaxseed was supplemented into the noodle mixture at three different concentrations (10, 15 and 20 g/100 g). RS content of the samples was in the range of 0.61-2.14 g/100 g and the highest RS was found for the sample having 10% flaxseed. Maximum TDF value was determined to be 8.28% for the noodle sample enriched with 20% of flaxseed while that of control was 1.68%. Estimated eGI of the samples was not significantly affected by the flaxseed fortification while mineral composition of noodle samples was significantly affected by the flaxseed addition (P < 0.05). The major mineral compounds present in the samples were sodium, potassium, magnesium and phosphorus. It could be concluded that the noodle enriched with 10% of flaxseed would be a healthier alternative product for consumption.

    • SDG 2 · Açlığa Son
    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus10WoS9OpenAlex11
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  • BildiriYalnız künye2019
    Measuring and improving operator performance on large mining equipment

    Kahraman, M.M.

    Mining as an industry is in the middle of commodity price upheaval that is wiping out many mining firms. Only the companies that have adapted right technology and data driven decision making culture will survive after each commodity price cycle. Latest technological solutions made it possible to track materials and equipment in every step of mining; from the face to plant to facilitate decision making process. Mines are investing in equipment monitoring technology with the expectation of gaining large increases in equipment productivity and reliability. Simply buying the technology does not result in achieving the promised benefits. Only a holistic approach can achieve these benefits, considering the people (analytical skills and culture), the process (deliberate means of using the data), and the platform (analytical technology). One of the principle methods for achieving this advantage is through increasing productivity and equipment health of major production equipment. This paper presents a case study using equipment monitoring technology as part of an operator performance system for a major machine asset: a dragline.

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  • MakaleAçık Erişim2018Scopus SJRQ2
    Experimental analysis for heat transfer of nanofluid with wire coil turbulators in a concentric tube heat exchanger

    Akyürek, Eda Feyza; Geliş, Kadir; Şahin, Bayram; Manay, Eyüphan

    Nanofluids are a novel class of heat transfer suspensions of metallic or nonmetallic nanopowders with a size of less than 100 nm in base fluids and they can increase heat transfer potential of the base fluids in various applications. In the last decade, nanofluids have become an intensive research topic because of their improved thermal properties and possible heat transfer applications. For comparison, an experiment using water as the working fluid in the heat exchanger without wire coils was also performed. Turbulent forced convection heat transfer and pressure drop characteristics of Al2O3-water nanofluids in a concentric tube heat exchanger with and without wire coil turbulators were experimentally investigated in this research. Experiments effected particle volume concentrations of 0.4–0.8 to 1.2–1.6 vol% in the Reynolds number range from 4000 to 20,000. Two turbulators with the pitches of 25 mm and 39 mm were used. The average Nusselt number increased with increasing the Reynolds number and particle concentrations. Moreover, the pressure drop of the Al2O3-water nanofluid showed nearly equal to that of pure water at the same Reynolds number range. As a result, nanofluids with lower particle concentrations did not show an important influence on pressure drop change. Nonetheless, when the wire coils used in the heat exchanger, it increased pressure drop as well as the heat transfer coefficient.

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  • MakaleAçık Erişim2016Scopus SJRQ1
    Geochronology and geochemistry of Eocene-aged volcanic rocks around the Bafra (Samsun, N Turkey) area: Constraints for the interaction of lithospheric mantle and crustal melts

    Temizel, Irfan; Arslan, Mehmet; Yücel, Cem; Abdioğlu, Emel; Ruffet, Gilles

    40Ar-39Ar age, whole-rock chemical, and Sr-Nd isotope data are presented for the post-collisional, Eocene (51.3-44.1 Ma)-aged volcanic rocks from the Bafra (Samsun) area in the western part of the Eastern Pontides (N Turkey) aiming to unravel their sources and evolutionary history. The studied Eocene volcanic rocks can be divided into two groups: analcime-bearing (tephritic lava flows and dykes) and analcime-free (basaltic to trachytic lava flows and basaltic dykes). The analcime-bearing volcanic rocks have a fine-grained porphyritic texture with clinopyroxene phenocrysts, whereas analcime-free volcanic rocks show a variety of textures including hyalo-microlitic microgranular porphyritic, intersertal, trachytic, fluidal, and glomeroporphyritic. The volcanic rocks also show evidence of mineral-melt disequilibrium textures such as sieved, rounded, and corroded plagioclases, partially melted and dissolved clinopyroxenes and poikilitic texture. Petrochemically, the parental magmas of the volcanic rocks evolved from alkaline to calc-alkaline lava suites and include high-K and shoshonitic compositions. They display enrichments in light rare earth and large ion lithophile elements such as Sr, K, and Rb, as well as depletions in high field strength elements such as Nb, Ta, Zr, and Ti, resembling subduction-related magmas. The analcime-bearing and -free volcanic rocks share similar incompatible element ratios and chondrite-normalised rare rearth element patterns, indicating that they originated from similar sources. They also have relatively low to moderate initial 87Sr/86Sr (0.7042-0.7051), high positive εNd(t) values (+0.20 to +3.32), and depleted mantle Nd model ages (TDM1 = 0.63-0.93 Ga, TDM2 = 0.58-0.84 Ga). The bulk-rock chemical and Sr-Nd isotope features as well as the high Rb/Y and Th/Zr, but low Nb/Zr and Nb/Y ratios, indicate that the volcanic rocks were derived from a lithospheric mantle source that had been metasomatised by slab-derived fluids. Trace element modelling suggests that the parental magma(s) of the volcanic rocks represent mixtures of melts derived by low-degree (~5-10%) partial melting of spinel-lherzolite (40-85%) and garnet-lherzolite (15-60%) mantle sources. Sr-Nd isotopic modelling also suggests that a 25-35% lower crustal component was added in the parental magmas; AFC modelling additionally indicates minor upper crustal contamination during the evolution of the volcanic rocks. In conclusion, integration of the geochemical, petrologic, and isotopic data with regional geology suggests that the analcime-bearing and -free volcanic rocks evolved from parental magma(s) derived from melts of a subcontinental lithospheric mantle and lower crustal sources.

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  • MakaleAçık Erişim2016Scopus SJRQ2
    Synthesis of new 1,2,4-triazole compounds containing Schiff and Mannich bases (morpholine) with antioxidant and antimicrobial activities

    Ünver, Yasemin; Deniz, Sadik; Çelik, Fatih; Akar, Zeynep; Küçük, Murat; Sancak, Kemal

    Compound 2 was synthesized by reacting CS2/KOH with compound 1. The treatment of compound 2 with hydrazine hydrate produced compound 3. Then, compound 3 was converted to Schiff bases (4a–d) by the handling with several aromatic aldehydes. The treatment of triazole compounds 4a–d containing Schiff base with morpholine gave compounds 5a–d. All compounds were tested for their antioxidant and antimicrobial activities. The antioxidant test results of DPPH• radical scavenging and ferric reducing/antioxidant power methods showed good antioxidant activity. The triazole-thiol (3) was the most active, and the effect of the substituent type of the thiophene ring on the activity was same for both Schiff bases (4a–d) and Mannich bases (5a–d). Among the newly synthesized triazole derivatives, the Schiff base 4d and the Mannich base 5d carrying nitro substituent on the thiophene ring showed promising antibacterial and antifungal activity, with lower MIC values than the standard antibacterial ampicillin.

    AtıfScopus99WoS94OpenAlex104
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  • MakaleAçık Erişim2019Scopus SJRQ3
    Optimum tuning of a gyroscopic vibration absorber for vibration control of a vertical cantilever beam with tip mass

    Ünker, F.; Çuvalcı, O.

    In this paper, a symmetric gyro with coupling to the tip mass of a beam mounted on a vibrating base is considered. Taking advantage of the angular momentum of the rotating gyroscope, gyrostabilizer systems are expected to become more widely actualized as they provide an effective means of motion control with several significant advantages for various structures. This paper mainly focused on finding optimized stiffness and damping values that minimize the vibration responses with the derivation of the frequency equations of a special combined gyro-beam system. Correctness of the analytical results is verified by numerical simulations. The comparison with the results from the derivation of the corresponding frequency equations shows that the optimized stiffness and damping values are very accurate.

    AtıfScopus8WoS5OpenAlex7
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  • Kitap BölümüYalnız künye2019
    Working capital management and firm performance of turkish companies

    Erdoğan, Mahmut

    Introduction Working capital management is vital for corporate finance because of its contribution to shareholder value by maintaining the balance between profitability and risk. In particular, firms that invest less in working capital are assumed to have higher returns and risks, while firms investing heavily in working capital are assumed to have lower returns and risks (Banos-Caballero et al., 2012). Effective working capital management is very important because it affects the performance and liquidity of the firm. The main objective of working capital management is to ensure the optimal balance among working capital components. Effective working capital management is an essential part of the overall company strategy to create shareholder value. Therefore, companies try to maintain the optimal working capital level to maximize their firm value (Vural et al., 2012). Effective working capital enables companies to be successful and to survive, while poor and mismanagement is the main reason for small business failures (Tahir and Anuar, 2016). The primary purpose of working capital management is to provide the appropriate liquidity for the company’s sustainability and activities and to fulfill its short-term financial liabilities. Therefore, current assets and short-term liabilities are important components of total assets and hence careful evaluation of total assets is of utmost importance. However, working capital management is a complex task because of an inverse relationship between liquidity and profitability. While the primary purpose of any company is profit maximization, it also needs to obtain the appropriate….

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  • BildiriYalnız künye2018
    Experimental Channel Measurement for Indoor Office Visible Light Communication

    Yazgan, Ayhan; Simsek, Cemaleddin; Albayrak, Cenk; Tugcu, Emin; Turk, Kadir

    Channel measurement for visible light communication (VLC) is theoretically and experimentally performed in a real office platform. Six armatures composed of phosphor based white LED arrays are fed by designed analog LED drivers. Measurements are taken in a 6m x 7.8m office room which is formed as 10×13 matrix with 60 cm grid distance for both simulation and experiment studies. The link distance between LED arrays and optical receiver is kept minimum 2.5 meters for each measurement. Experimental results are generally in good agreement with simulation results, which are obtained using Barry's theoretical channel model.

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