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In this study, the stable combustion ranges and emission values of JP8 fuel, which is used in military aviation, were tested and optimum conditions were determined. The AFR (Air/Fuel Ratio) of the JP8 flame was increased experimentally at constant thermal power in a gas turbine combustion chamber. In the study, AFR were tested as 30/1, 33/1, 36/1, 39/1 and 42/1. A generator with 0.4 swirl number is placed at the burner outlet. Under these conditions, the effect of external acoustic enforcement frequencies on dynamic instabilities at different AFR was investigated. Flame length and thickness data were extracted from the images obtained from the image processing technique. The effect of AFR change on the combustion chamber temperature was examined and pollutant emissions were measured. The results showed that the most stable flame appeared in AFR 33/1 case at 155 and 300 Hz resonance frequencies under acoustic enforcements. Additionally, when the AFR was increased to 42/1, flame instability increased at all frequency values. Moreover, it has been determined that the most optimum mixture in terms of combustion chamber exit temperature and CO emissions is AFR 33/1. There was an increase in NOX emissions by up to 39/1 with the increase in AFR.

The aim of our study is to discuss the use of artificial intelligence-supported platforms, which have become increasingly popular in recent months, in the context of ethics, opportunities, challenges, and the role of the researcher. In this context, we analysed platforms such as ChatGPT, ChatPDF, Consensus, SciSpace, and Scite Assistant. Within the scope of our analyses, we concluded that various regulations regarding the use of AI-supported platforms in scientific research should be enacted as soon as possible. Although such platforms offer opportunities for researchers, they also bring challenges such as referencing and reproducibility of scientific work. Besides, the use of AI-supported platforms in scientific research also puts the role of researchers into question.

The aim of this study is to find out the perceptions of secondary students about learning the English language through metaphor analysis. The research was carried out with 432 students studying in the 6th, 7th and 8th grades of 6 primary schools in Yozgat city centre. Qualitative method and survey model were used in the study; typical case sampling was used to form the study group. The data of the study were obtained with the data collection tool prepared by the researcher and finalized after expert opinion. In the data collection tool, students were asked to answer a semi-structured question reflecting their thoughts about learning English. The data obtained from the research were analyzed by content analysis method and descriptive analysis techniques were used to analyze the data. As a result of data analysis, metaphors were examined under five themes: challenging, progressive, beneficial, enjoyable, and intangible. The metaphors show that students generally have positive perceptions about learning English. These metaphors are substantial as they provide an in-depth understanding of students’ perceptions and shed light on teachers and curriculum designers

The increasing number of pandemic issues require to pay attention to health conditions and social distance. The explicit sign of COVID-19 is body fever. It is a simple and affordable detection method when compared to other blood tests. However, it is required to be physically close to a visitor to measure body temperature. For this reason, we have designed and developed a low-cost microprocessor measurement system with an infrared non-contact temperature sensor, and a Bluetooth for sending to long distance. Android application has been developed to read and set the alarm function using a smart telephone or a tablet far from the visitors. With the help of these circuit and application designs, body temperatures can be checked from long distance considering the pandemic situations. The printed circuit of the microcontroller, Bluetooth, sensor, and light-dependent resistor (LDR) triggering are manufactured, and the software of the controller and the application are integrated and tested successfully

In the current economic environment, the timeliness of corporate financial reporting is one of the important factors that have impact on the efficiency of financial markets. Delay in disclosure of financial statements prominently decreases the efficiency of financial markets. This study aims to analyze factors that influence timely corporate financial reporting by using a sample that includes 90 manufacturing firms listed on Borsa Istanbul over the period of 2014-2017. The results of regression analysis reveal that firm size, type of audit firm, board independency, profitability and leverage significantly affect the timeliness of financial statements. The findings of empirical analysis provide vital implications for regulatory agencies.

Objective: The aim of this study was to compare ultrasonographically measured quadriceps and patellar tendon thicknesses between Patellofemoral Pain Syndrome (PFPS) patients and age- and gender-matched healthy controls. Methods: Among patients who presented to physical therapy and rehabilitation outpatient clinic in January–December 2016, 61 volunteers (28 men and 33 women; mean age: 30.79 ± 6.55 years) who were eligible considering the inclusion and exclusion criteria were enrolled. 30 were diagnosed with PFPS, and the remaining were age- and gender-matched healthy volunteers. Mean age was 30.03 ± 5.67 years in healthy subjects and 45.2% were of male gender. The patient group had mean age of 31.57 ± 7.37 years and 46.7% of the patients were male. Q angles were measured at standing, supine and sitting positions. Patellar and femoral tendon thicknesses and areas were measured ultrasonographically. Kujala questionnaire were used to evaluate the functional status of the participants. Results: No significant difference was detected between groups regarding profession, educational background, and body mass indices (BMI) (p > 0.05). Q angle values were significantly higher in the patient group when compared to controls at standing (17.03 ± 3.84 vs. 13.87 ± 1.75°, p 0.05). Patellar tendon thickness values of ≥0.35 cm were found to have 66.7% sensitivity and 67.7% specificity for PFPS diagnosis in the ROC curve analysis (area under curve: 0.771, 95% confidence interval: 0.655–0.887, p

Distance education (DE), which has evolved under the wings of information technologies in the last decade, has become a fundamental part of our modern education system. DE has not only replaced the traditional education method as in social sciences and lifelong learning opportunities but also has significantly strengthened traditional education in mathematics, science, and engineering fields that require practical and intensive study. However, it is deprived of supporting some key elements found in traditional educational approaches such as (i) modern computer laboratories with installed special software suitable for the student’s field of interest; (ii) adequate staff for maintenance and proper functioning of laboratories; (iii) face-to-face technical support; (iv) license fees. For students to overcome these shortcomings, a virtual application pool is needed where they can easily access all the necessary applications via remote access. This research aims to develop a platform-independent virtual laboratory environment for DE students. This article has been developed specifically to guide DE institutions and to make a positive contribution to the literature. Technology Acceptance Model (TAM) has been used to explain student behaviors. It was concluded that students using the platform performed more successful grades (12.89%) on laboratory assessments and that the students using the developed platform were found to be more satisfied with the education process.

In this study, the fire resistance of slag‐based geopolymer mortars was investigated and the effect of silica fume (SF) and waste rubber (WR) on this resistance was determined. In slag‐based geopolymer mortars activated using 12M NaOH solution, 0%, 5%, and 10% by weight SF was substituted for slag; 0%, 5%, 10%, and 15% WR by volume were substituted for fine aggregate. The samples that completed the curing period were exposed to temperatures of 250°C, 500°C, and 750°C for 1 h, and the mechanical (compressive, flexural and splitting tensile strengths, and impact resistance), physical (weight change and sorptivity) and microstructure (scanning electron microscopy [SEM] and energy dispersive spectroscopy [EDS]) properties of these samples were examined. The compressive strengths of the samples without WR were between 48.10 and 60.97 MPa, and the samples without SF were between 28.52 and 48.10 MPa. Strength losses at 750°C were between 51.5% and 73.5%. As the SF substitution increased, the samples' mechanical and physical properties improved, whereas as the WR substitution increased, the samples' mechanical and physical properties declined. While the SF substitution had a positive effect on the fire resistance of the samples, the WR substitution had a negative effect. It is thought that the choice of geopolymer binder as a binder in the mortar and the use of waste tires as aggregate contribute to the literature in terms of both preventing environmental pollution and ensuring the recycling of these materials. [ABSTRACT FROM AUTHOR]

UMS 12 Gelir Vergileri standardı, işletmelerin ödeyecekleri kurumlar vergisinin muhasebeleştirilmesine yönelik düzenlemeleri içermektedir. İşletmelerin cari dönem vergi yükümlülüğünün mali tablolarda nasıl sunulacağı, mali kar ile muhasebe karı arasındaki farklardan kaynaklanan ertelenmiş vergi varlığının ve ertelenmiş vergi yükümlülüğünün muhasebeleştirilme süreci önem arz etmektedir. İşletmelerin vergi mevzuatına göre hesaplanmış olan karları ile muhasebe standartlarına göre hesaplanmış olan karları arasındaki farklara geçici veya sürekli farklar neden olmaktadır. UMS 12 Gelir Vergileri Standardında yer alan geçici ve sürekli farkların mali tablolara etkisi, bu çalışmada incelenecek konular arasında yer almaktadır. Bu çalışmada ayrıca ertelenmiş vergi varlıklarının ve ertelenmiş vergi borçlarının teorik yapısı uygulamalı örneklerle analiz edilmektedir.