Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(115)
- Kaya, Yunus(50)
- Ayata, Ümit(48)
- Şahin, Engin(48)
- İspirli, Hümeyra(46)
- Bayraktar, Bülent(42)
- Şenay, Volkan(41)
- Can, Zehra(39)
- Özen, Soner(37)
- Bayram, Sinan(35)
- Pat, Suat(35)
- Öztürk, Mesut(35)
- Ecem Bayram, Nesrin(34)
- Esmer, Yusuf(34)
- Battal, Fetullah(33)
- Artar, Musa(32)
- Öner, Erdal(32)
- Korkmaz, Şadan(31)
- Yilmaz, Mustafa Tahsin(31)
- Ertugrul, Mehmet(30)
- Mercan, Emin(30)
- Hasar, Ugur Cem(29)
- Kutlu, Naciye(28)
- Özdemir, Akın(27)
- Kul, Murat(26)
- Cuce, Erdem(25)
- Kamiloğlu, Aybike(25)
- Bayram, Ozkan(24)
- Sefali, Abdurrahman(24)
- Sert, Durmuş(24)
- Çolak, Murat(24)
- Ayazoglu, Rabil(22)
- Gıdık, Betül(22)
- Maden, Sedat(22)
- Ustabulut, Mete Yusuf(22)
- Uçurum, Metin(22)
- Akeren, Zahide(21)
- Dirican, Ebubekir(21)
- Kara, Yakup(21)
- Abdioglu, Murat(20)
Yayınlar
- MakaleYalnız künye2023Scopus SJRQ3The determinants of non-family employees' turnover intentions in family firms
Yazici, Omer; Memili, Esra; Patel, Pankaj C.; Ramadani, Veland
While research on the organisational behaviour and HRM (i.e., organisational identification, justice, commitment, and turnover intentions) in family business contexts has been advancing, the empirical investigation of non-family employees’ perceptions is still scarce. Drawing upon family business-influenced literature and organisational identification, justice, and commitment theories, we explore the determinants of non-family employees’ turnover intentions. Specifically, we examine the impact of non-family employees’ family firm identification and perceived justice on family firm commitment, in turn affecting turnover intentions. Furthermore, we examine the moderation effects of perceived family influence on these links. Our findings demonstrate that non-family employees’ family firm identification and perceived justice positively affect their family firm commitment, which in turn lowers turnover intentions. While family firm commitment mediates the relationship between family firm identification and turnover intentions, perceived family influence moderates the mediation effects of family firm commitment between family firm identification and turnover intentions. 2023 Inderscience Enterprises Ltd.
AtıfScopus1
İncele - MakaleYalnız künye2023Scopus SJRQ2Design, synthesis, antioxidant and anticholinesterase activities of novel isonicotinic hydrazide-hydrazone derivatives
Aslanhan, Özlem; Kalay, Erbay; Tokalı, Feyzi Sinan; Can, Zehra; Şahin, Engin
The design and synthesis of hydrazone derivatives are increasing in popularity day by day due to the significant biological activities of this scaffold. In the present study, twelve novel isonicotinic hydrazide-hydrazone analogues were synthesized by the condensation reaction of isonicotinic hydrazide with benzaldehyde possessing sulfonate moiety. The structures of the novel compounds have been characterized in detail using spectroscopic techniques. All compounds have shown inhibitory effects against the AChE enzyme at rates ranging from 21.00 to 59.48%. Among them, compound 5 has exhibited the best inhibitory effect of 59.48% against AChE at a concentration of 0.1 mM. Furthermore, to determine how effective the novel compounds are as antioxidants, FRAP and DPPH studies were also carried out. FRAP values in compounds 1–12 were found to range from 26.989–3415.556 µmol FeSO4.7H2O/mg. They also displayed moderate antioxidant potential in the range of SC50=0.03–87.32 mg/mL compared with the control Trolox (SC50 =0.004) in DPPH radical scavenging activities. It was seen that the AChE inhibition percentages of the compounds were in the range of 23.04–58.10% at 0.1 mM concentration. This is the first research on the synthesis, antioxidant and enzyme inhibition properties of these compounds.
AtıfScopus43WoS37OpenAlex44İncele - MakaleAçık Erişim2023Scopus SJRQ2Preparation of Eumelanin-Encapsulated Stereocomplex Polylactide Nano/Microparticles for Degradable Biocompatible UV-Shielding Products
Putri, Oceu Dwi; Petchsuk, Atitsa; Buchatip, Suthawan; Supmak, Wilairat; Kaewsaneha, Chariya; Thananukul, Kamonchanok; Nim, Bunthoeun; Bayram, Sinan; Thumanu, Kanjana; Opaprakasit, Pakorn
The role of eumelanin as a natural pigment in protecting human skin from ultraviolet (UV) light has drawn vast interest in the research and industrial community. Encapsulation of the compound by various shell materials has been extensively studied to optimize and prolong its shielding efficiency from UV penetration through the skin. Polylactide (PLA)-based copolymers have been widely used in the encapsulation of various active compounds due to their biocompatibility and biodegradability that facilitate sustained release of the active compounds. In this work, stereocomplex PLA (sc-PLA) derived from mixtures of poly(D-lactide-caprolactone-D-lactide), P(DLA-b-CL-b-DLA), a triblock copolymer with linear poly(L-lactide), and PLLA are employed to encapsulate eumelanin by an oil-in-water emulsion (O/W) technique. The effect of eumelanin distribution in PLA's enantiomers and ultrasonication on the physicochemical properties, encapsulation efficiency, and release behavior of the nano/microparticles were evaluated. The potential application of the resulting particles for sunscreen products was assessed in terms of UV absorbance and in vitro sun protection factor (SPF). The nano/microparticles show a hollow spherical structure, whose size can be controlled by ultrasonication. The distribution of eumelanin and the ultrasonication process play a key role in the growth of sc-PLA and the crystalline structure of the particles. The highest encapsulation efficiency of 46.6% was achieved for sc-PLA2U particles. The high content of eumelanin and the hollow structure with a large surface area lead to improvement in the UV absorbance and sunscreen performance of the particles, as revealed by the increase in the SPF value from 9.7 to 16.5. The materials show high potential for various applications, especially in cosmetic and pharmaceutical fields, as UV-shielding products.
AtıfScopus3WoS3OpenAlex3İncele - MakaleYayıncıda açık erişim2023Scopus SJRQ4Development of Alkali-Activated Binders from Recycling Regional Tuff and Marble Wastes
Tekin, İlker; Ciza, Baraka; Gökçe, H.S.
The sustainability goals of the developing world have led many industries to recycle their wastes and reduce emitting greenhouse gases. To contribute to these environmental responsibilities, this study has focused on the development of eco-friendly binder materials from regional ground tuff and marble wastes by the activation of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) or slaked lime (Ca(OH)2). The results of this study show that alkali-activated composites experienced expansion, drying shrinkage cracking, leaching, and efflorescence. The compressive strength values of the NaOH and Ca(OH)2-activated pastes reached up to 15 MPa and 9 MPa, respectively. A reduction in NaOH molarity improved the compressive strength, dimensional stability, and durability of tuff-based alkali-activated pastes.
AtıfScopus5OpenAlex3İncele - MakaleAçık Erişim2023Scopus SJRQ1A comprehensive study on structural properties, photon and particle attenuation competence of CoNiFeCr-Ti/Al high entropy alloys (HEAs)
Sakar, Erdem; Guler, Omer; Alım, Bünyamin; Say, Yakup; Dikici, Burak
It is well known that high entropy alloys (HEAs) have a wide range of potential applications as radiation shielding due to their superior properties. The CoNiFeCr-Ti/Al compositions were chosen for their low cost as HEA in this study. The HEAs were successfully produced using the mechanical alloying (MA) method with equimolar CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi compositions. The production and structural properties of the alloys were investigated in detail. Besides, the photon and particle radiation shielding properties of the HEAs were calculated with the help of Phy-X/PSD, SRIM (10 keV-20 MeV), and ESTAR (10 keV-20 MeV) programs. The photon-matter interaction parameters were calculated in both specific photon energies emitted from 241Am, 133Ba, 109Cd, 60Co, 137Cs, 131I, and 22Na nuclides and a continuous energy range of 15 keV-15 MeV. The characterization of the alloys was investigated by using X-ray diffraction (XRD) and scanning electron microscopes (SEM) attached to an energy dispersive spectroscopy (EDX). It was found that the HEAs have a highly amorphous structure due to the selected production method. The crystal size of the alloys was calculated as 70, 35, and 20 nm for CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi, respectively. In terms of shielding properties, it has been determined that the produced HEAs have better shielding characteristics for photon and particle radiations than standard shielding concretes. In addition, the results demonstrated that CoNiFeCr alloy, which has the best shielding ability among the HEA alloys, can be used as a shielding material application requiring photon, electron, proton, alpha, and neutron radiations.
AtıfScopus30WoS32OpenAlex32İncele - MakaleAçık Erişim2023Scopus SJRQ3Isolation and characterization of yogurt starter cultures from traditional yogurts and growth kinetics of selected cultures under lab-scale fermentation
Kayacan Çakmakoğlu, Selma; Vurmaz, Melike; Bezirci, Emine; Kaya, Yasemin; Dikmen, Hilal; Göktaş, Hamza; Demirbaş, Fatmanur; Encu, Betül; Acar Soykut, Esra; Alemdar, Filiz
The development of new starter cultures is a crucial task for the food industry to meet technological requirements and traditional products are important reservoirs for new starter cultures. In this respect, this study aimed to isolate, identify, and determine the technological characteristics of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains originated from traditional yogurt samples. Genotypic discrimination of 200 isolates revealed the presence of distinct 19 S. thermophilus and 11 Lb. delbrueckii subsp. bulgaricus strains as potential starter cultures. Strain-specific properties determined the acidification capacity of the yogurt starter cultures and a higher acidification capacity was observed for S. thermophilus strains compared to Lb. delbrueckii subsp. bulgaricus strains. Proteolytic activity was found between 0.012–0.172 and 0.078–0.406 for S. thermophilus and Lb. delbrueckii subsp. bulgaricus strains, respectively. 4 of S. thermophilus and 3 of Lb. delbrueckii subsp. bulgaricus strains were found resistant to all tested bacteriophages. The antibiotic susceptibility tests of the isolates revealed that a very low antibiotic resistance was observed for the yogurt starter cultures. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected S. thermophilus and Lb. delbrueckii subsp. bulgaricus was calculated as 0.527 h−1 and 0.589 h−1, respectively.
AtıfScopus8WoS10OpenAlex11
İncele - MakaleAçık Erişim2023Scopus SJRQ2Determination of toxicity and radioprotective properties of bacterial and fungal eumelanin pigments
Bayram, Sinan; Aygün, Bünyamin; Karadayi, Mehmet; Alaylar, Burak; Güllüce, Medine; Karabulut, Abdulhalik
Purpose: Determination of the protective property of melanin, an organic polymer class consisting of phenolic and/or indolic compounds isolated from bacteria and fungi, against fast neutron radiation. To show that these melanin samples, which also have antioxidant and metal chelating properties, can be used as an active ingredient for a drug to be developed against neutrons used in nuclear research and medicine. Materials and methods: Bacterial and fungal media were prepared, and melanin pigments were produced and isolated. For molecular characterization of pigments, bacterial genomic DNA extraction, 16S rDNA gene amplification processes, and fungal genomic DNA extraction, ITS1, and ITS4 Gene Regions amplification were performed. The DEL assay was implemented to determine the genotoxicity properties of bacterial and fungal melanin pigments. Samples were prepared in a pad measuring 10 ml volume (60 × 15 mm) at a concentration of 0.2–1 microgram in 1% agarose gel for radiation-absorbed dose measurements. Absorption measurements were made using 241Am-Be fast neutron source and Canberra brand NP series BF3 gaseous detector to determine the neutron radiation absorption capacity of all samples. The results obtained to determine the absorption degrees of melanin samples were compared with paraffin and normal concrete, which are widely used in neutron radiation shielding studies. Results: Melanin pigments were obtained using different bacteria and fungi strains. Afterwards, the fast neutron radiation absorption capacity of these purified pigments were determined. Compared to reference samples, these pigments were found to have slightly lower radiation absorbing ability. In addition to these experiments, cytotoxicity tests were carried out using the Yeast DEL assay technique to evaluate the potential for use of these organic pigments in fields such as medicine and pharmacology. According to the results obtained from the tests, it was determined that these melanin samples did not have any toxic effects. Conclusion: It was determined that these melanin samples have the potential to be used as a radioprotective drug active substance to protect the tissues and cells of people exposed to neutron radiation after a nuclear accident or nuclear war. Giving a drug that will be developed by using these active ingredients before or after people are exposed to a radiation environment can provide great benefits.
AtıfScopus12WoS12OpenAlex17İncele - MakaleAçık Erişim2023Scopus SJRQ3Harmonic trigonometrically convexity
Kadakal, Huriye
In this study, we introduce and study the concept of harmonic trigonometrically convex functions and their some algebric properties. We prove two Hermite-Hadamard type inequalities for the newly introduced class of functions. We also obtain some refinements of the Hermite-Hadamard inequality for functions whose first derivative in absolute value, raised to a certain power which is greater than one, respectively at least one, is harmonic trigonometrically convex.
AtıfScopus10WoS12OpenAlex11İncele - MakaleYalnız künye2023Scopus SJRQ2Effective Damping Coefficient of Fluid Viscous Dampers for Dynamic Response Mitigation of Coupled Frames
Düzgün, Oğuz Akın; Hatipoğlu, Yavuz Selim
Purpose: In this study, the effective damping coefficient of the fluid viscous dampers (FVDs) used for coupling two adjacent multi-story frames was investigated, considering soil-structure interaction (SSI) effects under seismic excitation. Methods: A numerical procedure was employed to obtain the dynamic response of the interconnected frames-soil system. The two-dimensional (2D) finite elements were used for the numerical treatment of the adjacent frames and soil region. Viscous boundary conditions were used as special non-reflecting boundaries on the edges of finite soil region. Five different damping coefficients of FVDs are considered to determine the effective damping coefficient. The effective damping coefficient of FVDs was determined by comparing the results from coupled frames with those of the uncoupled frames. Results: The results showed that the most affecting parameter on the system response was found to be soil type. It was also found that the sufficient damping coefficient of the viscous damper is equal to 1 × 105 N s/m for minimum response. Conclusion: When the effective damping coefficient of the FVDs was provided, the maximum values of the roof displacements, the roof accelerations, and the base shear forces are found to decrease by more than 40%.
AtıfScopus3WoS2OpenAlex4İncele - MakaleAçık Erişim2023Scopus SJRQ2Relationship between middle school students’ metacognition and problem-posing performance: A serial mediation analysis
Ada Yıldız, Kübra; Öztürk, Mesut
This study tests a model that predicts the problem-posing performance of sixth-grade students (independent variable metacognition, mediator variables mathematics and native language course success scores at the end of the year). The research was conducted with the relational model. The results regarding the mediation effect indicated that the mathematics course success scores and the native language course success scores were separately full mediators in the effect metacognition has on problem-posing performance. The results regarding serial mediation effect revealed that the mathematics course success scores and native language course success scores had a full mediating effect on the effect of metacognition on problem-posing performance.
AtıfScopus3OpenAlex2İncele - MakaleYalnız künye2023Scopus SJRQ2Development of the diabulimia knowledge level scale
Çetinkaya Özdemir, Serap; Semerci, Vahide; Sönmez Sarı, Ebru
The aim of this study was to develop the Diabulimia Knowledge Level Scale. The nurses voluntarily participated in the research (n = 384). The Diabulimia Knowledge Level Scale consists of 19 items and four factors. The four factors that make up the scale according to the results of Exploratory Factor Analysis explain 68.53 % of the total variance. The total Cronbach alpha coefficient of the scale was found to be 0.92. The Diabulimia Knowledge Level Scale is the first scale developed to determine the level of diabulimia knowledge among nurses. The scale is valid and reliable.
AtıfScopus2WoS2OpenAlex3İncele - MakaleAçık Erişim2023Testing of waste vegetable oils as color modifiers in American walnut (Juglans nigra L.) wood; [Amerikan ceviz (Juglans nigra L.) odununda renk değiştirici olarak bitkisel atık yağların denenmesi]
Peker, Hüseyin; Esteves, Bruno; Ayata, Ümit
American walnut (Juglans nigra L.) wood is used for veneer due to its beautifully grained and dark-colored wood. This study was conducted to test the use of plant waste oils as color modifiers on American walnut wood. As waste vegetable oils, discarded walnut, olive, corn, and sunflower oils were employed. After applying waste oils to the wooden surfaces, several surface properties (brightness, color, and whiteness index: WI*) were determined. It was observed that multivariate analysis of variance tests conducted for WI* values and color parameters were found to be statistically significant. For all vegetable waste oils, decreases were identified in L*, C*, ho, and b* parameters, as well as in WI* values and glossiness values (for all degrees and orientations). The ∆E* values were measured at 19.18 for sunflower, 22.02 for walnut, 22.65 for corn, and 19.49 for olive. Each of the discarded vegetable oils had an impact on the color of the wooden surface. Keywords.
AtıfScopus2OpenAlex2
İncele - MakaleAçık Erişim2023A New Approach on Some Special Curves
Aydın, Tuba Ağırman; Kocayiğit, Hüseyin; Kara, Meryem
In this paper, we obtain some characterizations for a Frenet curve with the help of an alternative frame different from the Frenet frame. Also, in the present study, we consider weak biharmonic and harmonic 1-type curves by using the mean curvature vector field of the curve. We also study 1-type and biharmonic curves whose mean curvature vector field is in the kernel of Laplacian. We give some theorems for such curves in the Euclidean 3-space. Moreover, we give the classifications of these types of curves.
- MakaleAçık Erişim2023Scopus SJRQ2Morin ameliorates methotrexate-induced hepatotoxicity via targeting Nrf2/HO-1 and Bax/Bcl2/Caspase-3 signaling pathways
Kızıl, Hamit Emre; Caglayan, Cuneyt; Darendelioğlu, Ekrem; Ayna, Adnan; Gür, Cihan; Kandemir, Fatih Mehmet; Küçükler, Sefa
Background: Organ toxicity limits the therapeutic efficacy of methotrexate (MTX), an anti-metabolite therapeutic that is frequently used as an anti-cancer and immunosuppressive medicine. Hepatocellular toxicity is among the most severe side effects of long-term MTX use. The present study unveils new confirmations as regards the remedial effects of morin on MTX-induced hepatocellular injury through regulation of oxidative stress, apoptosis and MAPK signaling. Methods and results: Rats were subjected to oral treatment of morin (50 and 100 mg/kg body weight) for 10 days. Hepatotoxicity was induced by single intraperitoneal injection of MTX (20 mg/kg body weight) on the 5th day. MTX related hepatic injury was associated with increased MDA while decreased GSH levels, the activities of endogen antioxidants (glutathione peroxidase, superoxide dismutase and catalase) and mRNA levels of HO-1 and Nrf2 in the hepatic tissue. MTX treatment also resulted in apoptosis in the liver tissue via increasing mRNA transcript levels of Bax, caspase-3, Apaf-1 and downregulation of Bcl-2. Conversely, treatment with morin at different doses (50 and 100 mg/kg) considerably mitigated MTX-induced oxidative stress and apoptosis in the liver tissue. Morin also mitigated MTX-induced increases of ALT, ALP and AST levels, downregulated mRNA expressions of matrix metalloproteinases (MMP-2 and MMP-9), MAPK14 and MAPK15, JNK, Akt2 and FOXO1 genes. Conclusion: According to the findings of this study, morin may be a potential way to shield the liver tissue from the oxidative damage and apoptosis.
AtıfScopus74WoS71OpenAlex82İncele - MakaleAçık Erişim2023Scopus SJRQ2A simulation study on colloid diffusion under time-varying optical potentials
Yücel, Harun
With its momentum transfer, light is a primary tool for manipulating microscale objects in various research fields, including physics, chemistry, and biology. Optical force fields, also known as energy landscapes, play a crucial role in manipulating micro- and nano-sized objects, enabling the sorting of mixed micro-sized particles. This study investigates the effect of time-varying periodic optical fields created by a structured light illumination technique on the diffusion motion of micro-sized colloidal particles suspended in a liquid. A simulation code is developed to calculate the optical force acting on particles due to any time-varying optical force field. Simulations are performed to produce trajectories of particles of different sizes suspended in a liquid for different illumination patterns. The results show that the average velocities of the particles depend on the projected optical pattern parameters and that mixtures of particles of different sizes can be separated using time-varying sequential patterns, thereby improving particle separation resolution.
AtıfScopus2WoS2OpenAlex3İncele - MakaleYalnız künye2023Scopus SJRQ1Gamma-ray and neutron shielding capability of blended cement-stabilized barite fillers developed by maximum density method
Gökçe, H.S.; Öksüzer, N.; Kamiloğlu, H.A.; Yılmaz, F.
The disposal of radiological wastes in the deep geological repositories has become an important issue for the reduction of hazardous risks on the human and biological environments. In this study, blended cement-stabilized barite fillers against gamma rays and neutrons have been developed with the use of the maximum density method by considering various amounts of water (100–300 kg/m3), binder (4–10%), and compaction energy (500–2000 kJ/m3). According to the experimental series of these filler materials, satisfactory response surface results have been achieved in the study. The experimental results revealed that compacted filling material can ensure an efficient shielding capability for gamma rays and neutrons when designed with a density of 3.064 g/cm3. An increase in binder content, water content, and compaction energy has improved the compressive strength of these materials up to 37 times according to that of the poorest series. Neutron and gamma-ray shielding capabilities were found to be 119 and 14% higher than those of the poorest filler material, respectively when theoretical and experimental results are considered in the study.
AtıfScopus4WoS3OpenAlex5İncele - MakaleAçık Erişim2023The effects of artificial weathering on the pendulum hardness of chestnut wood applied with polyurethane varnish after heat treatment; [Isıl işlem sonrası poliüretan vernik uygulanmış kestane odununda salınımsal sertlik üzerine yapay yaşlandırmanın etkileri]
Ulay, Göksel; Ayata, Ümit
The effects of artificial weathering (576 h) on the pendulum hardness values of Anatolian chestnut (Castanea sativa Mill.) wood applied with polyurethane varnish (PU) after heat treatment at 190°C for 1.5 h and at 212°C for 2 h were investigated. The results revealed that heat treatment, weathering period, and interaction were significant. The hardness values of the heat-treated materials were higher than those of the non-heat-treated test samples. The highest hardness value was determined in the un-weathered group of the test samples that were heat-treated at 190°C for 1.5 h while the lowest value was determined in the group that was heat-treated at 190°C for 1.5 h and weathered for 432 h. The highest reduction rates after weathering were obtained on samples that were heat-treated at 190°C for 1.5 h, followed by heat-treated at 212°C for 2 h and non-heat-treated. It was observed that the heat treatment application caused different pendulum hardness values in chestnut wood samples covered with polyurethane varnish.
AtıfScopus3OpenAlex2İncele - MakaleAçık Erişim2023Scopus SJRQ1Food Price Bubbles: Food Price Indices of Turkey, the FAO, the OECD, and the IMF
Akyol Özcan, Kübra
Food price bubbles are a phenomenon in which the cost of some food items or food commodities climbs quickly and unreasonably before collapsing due to reasons such as speculation, supply and demand imbalances, meteorological occurrences, and governmental actions. Governments and academics keep an eye on food prices to spot and address these bubbles. The aim of this paper is to analyze the food price bubble phenomenon despite the global slowdown by examining its origins, consequences, and policy solutions. The study’s contribution lies in its investigation of the presence of a potential bubble formation in food prices, which have experienced a surge globally and particularly in Turkey in recent years. The research examines the behavior of bubble formation in food prices in Turkey, the FAO, the OECD, and the IMF between 1992 and 2022 using the ADF, SADF, and GSADF tests. These tests can help identify when asset prices deviate significantly from their fundamental values and may be at risk of a sharp correction. The TUR, FAO, OECD, and IMF variables all show distinct bubble formations, with the TUR variable having 130 periods from 1995 to 2006, the FAO having 8 price bubble occurrences, the OECD having 12 different bubble formations, and the IMF having 4 distinct bubble formations. The results indicate the existence of food price bubbles that demonstrate disparities from their inherent values grounded in market fundamentals.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2023Scopus SJRQ2Magnetic Force Performance of Hybrid Multisurface HTS Maglev System With Auxiliary Onboard PMs
Ozturk, U. Kemal; Abdioglu, Murat; Mollahasanoglu, Hakki
The vertical levitation force, guidance force, and magnetic stiffness values, and thus the loading capacity and movement stability of high-temperature superconducting (HTS) Maglev systems, are aimed to be increased in this study by using auxiliary permanent magnets (PMs) in the onboard unit together with the multisurface HTS-permanent magnetic guideway (PMG) arrangement (hybrid multisurface arrangement). First, the magnetic levitation force, guidance force, and stiffness performances of the hybrid multisurface arrangement were investigated at different field cooling heights (FCH). Then, to compensate for the negation of instability that results from the higher repulsive force between the onboard PMs and the PMG and to obtain an optimal magnetic field medium, we have changed the vertical position of the auxiliary onboard PMs (ZPM) to ZPM = 0, 2, and 4 mm, at the cost of a bit of adecrement in the vertical levitation force. The bigger levitation force, together with the guidance force values for FCH = 25 mm and ZPM = 0 mm, indicates that the hybrid multisurface HTS-PMG arrangements are beneficial to increasing the practical applicability of Maglev systems.
AtıfScopus16WoS14OpenAlex14İncele - MakaleAçık Erişim2023Scopus SJRQ3Examination of the Effectiveness of School Leadership: A Second-order Meta-analysis Study
Kaya, Metin
This study aimed to examine the effectiveness of school leadership by exploring the relationships between various school leadership models and practices and different school outcomes, including organizational, teacher, and student outcomes. Data for this study were retrieved from multiple databases, including Web of Science, Scopus, ERIC, Academic Search Ultimate, and TR Dizin-Turkish national index. The analysis synthesized findings from 23 meta-analysis studies, utilizing second-order meta-analysis with the random-effects model. The study revealed a significantly positive relationship between school leadership and school outcomes, with a high level of correlation (mean effect size: 0.46). Additionally, this relationship varied significantly based on the type of school leadership, school outcome, and the quality of the studies conducted.
AtıfScopus2WoS1OpenAlex2İncele