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Enhancing Heat Transfer Across Applications with Triply Periodic Minimal Surface (TMPS) Structures: A Comprehensive Review
No full textThe current research evaluates how triply periodic minimal surface (TPMS) structures, specifically Gyroid configurations, enhance heat transfer in thermal management systems by addressing heating issues caused by miniaturized electronic devices. TPMS structures composed of Gyroid and Fischer-Koch varieties demonstrate up to a 50.6 % improvement in cooling efficiency compared to traditional fin structures. Additionally, the FischerKoch structure facilitates internal flow heat transfer, achieving efficiency levels 12 times greater than conventional designs. The Nusselt number exceedes 80 in TPMS configurations, although pressure drops increases when porosity fell below 0.7. However, the performance evaluation criterion remains above 70 at porosities of 0.8. The effective thermal management of advanced electronic systems benefits from the integration of phase change materials (PCMs) with TPMS structures, as they enhance heat dissipation and reduce melting durations. The review concludes that implementing TPMS components would significantly improve heat transfer, besides enabling designers to optimise thermal management systems within constrained spaces.Science Citation Index Expande
Thiamine (Vitamin B1) Levels and Sensory Properties of Cooked Rice: Exploring Varietal Differences
No full textThe composition and cooking quality of rice varieties vary highly. Preparation and cooking techniques may lead to thiamine degradation. In this study, rice meals were prepared with three different rice varieties grown in T & uuml;rkiye (Baldo, Osmancik, and Cammeo), four different fats (sunflower oil, margarine, butter, and olive oil), and two different cooking methods (Salma and Roasted), and thiamine amount and sensory attributes were investigated. Thiamine levels of raw rice were measured as 0.399 +/- 0.0210, 0.299 +/- 0.0010, and 0.303 +/- 0.0070 mg/100 g in Baldo, Osmancik, and Cammeo, respectively. The thiamine amount varied between 0.038 +/- 0.0020 and 0.176 +/- 0.0020 mg/100 g in rice meals, and the highest value was observed in Osmancik rice cooked with margarine using the Roasted method. Descriptive sensory analysis (DSA) assessed 8 taste attributes. Salma-cooked samples had a higher intensity of starchy and butter taste than the Roasted-cooked ones. Roasted-cooked rice meals had a higher intensity of sweet, salty, margarine, olive oil, sunflower oil, and roasted taste than the Salma-cooked samples.Science Citation Index Expande
Portfolio Optimisation in the Cryptocurrency Market: Hybrid Integration of Markowitz and Ridge Methods
No full textConstructing an effective asset allocation strategy requires buildingwell-diversified portfolios that maintain robust performance beyond the sample data. The classical Markowitz portfolio optimisation, while widely used, is known to suffer from issues such as estimation errors and sensitivity to multicollinearity, which can significantly distort the allocation process and reduce performance reliability. In order to surmount the aforementioned challenges, the incorporation of Machine Learning echniques, specifically Ridge regression, into the portfolio creation process has been effected. This has resulted in the provision of a hybrid model that combines the strengths of Markowitz optimisation and Ridge regression. The integration of these approaches within the hybrid model serves to mitigate the prediction risks while maintaining the diversification benefits inherent to the Markowitz framework. The model was trained using an 80/20 split and cross-validation was employed to prevent overfitting. The findings indicate that this integrated approach attains the maximum Sharpe ratio, thereby significantly enhancing risk-adjusted returns and portfolio stability when applied to cryptoasset returns. The findings emphasise the merits of integrating classical optimisation methodologies with machine learning to develop more robust and adaptive asset allocation strategies. By analysing the impact of high-volatility cryptoassets on portfolio performance, it makes important contributions to both the literature and practical portfolio strategies for investors.Emerging Sources Citation Inde
Hymenoplasty Experience: Factors Associated with Dehiscence (Hymenoplasty Complications)
No full textPurpose: To evaluate outcome of hymenoplasties in private clinics and investigate the factors affecting the risk of dehiscence Method: A retrospective cross-sectional survey of Obstetrics and Gynecology specialists trained over the last five years was conducted. Specialists from private clinics completed surveys on hymenoplasties performed. Rates and types of complications were requested and factors associated with wound dehiscence in patients undergoing permanent hymenoplasty was investigated with multivariate analysis. Results:. A total of 968 patients were included. Hymenoplasty was performed for revirgination in 874 cases (90.2%), incision of the hymen for gynecological procedures in 82 (8.4%) cases and trauma in 12 cases (1.2%). Complications included wound dehiscence (26.1%), infection (1.7%), bleeding (1.7%), pain (1.5%), itching (1.4%) and dyspareunia (0.5%). The technique was permanent in 714 cases and temporary in 254 cases. Among the permanent hymenoplaty cases, multivariate logistic regression analysis showed that obesity (OR=3.1, 95%CI: 1.5-6.2, p=0.001) and tobacco use (OR=2.2, 95%CI: 1.3-3.8, p=0.003) increases the risk of dehiscence. Sedation decreased the risk of dehiscence when compared to local infiltration anesthesia (OR=0.56, 95%CI: 0.33-0.99, p=0.04). Every decrease in the polyglactin suture caliber decreased the risk of dehiscence (OR=0.22, 95%CI: 0.16-0.3, p<0.001) This study showed that using 5.0 sutures, omitting infiltration anesthesia, and avoiding tobacco use may help decrease wound dehiscence after hymenoplasty
The Relationship Between Conflict Management Styles Used by Nurse Managers in Psychiatric Clinics and the Stress Level of Their Subordinates
No full textObjectives: This study aimed to determine the relationship between the opinions of nurses working in psychiatric wards regarding their managers' conflict management styles and their self-perceived stress levels. Methods: This was a descriptive, comparative, and correlational study. The population consisted of 580 nurses work- ing in psychiatric clinics of public and private hospitals in Istanbul, and 199 nurses were included in the sample. The \"Personal Information Form,\" \"Rahim Organizational Conflict Inventory–II (ROCI-II) Form A,\" and \"Perceived Stress Scale\" were used for data collection. Data were analyzed using frequency and percentage distributions, the Kruskal–Wallis test, Spearman correlation analysis, and the Mann–Whitney U test. Results: The participants’ mean scores on the Conflict Management Scale were as follows: integration subscale 2.50±0.90; obliging subscale 3.03±0.74; dominating subscale 2.92±0.85; avoiding subscale 2.98±0.66; and compro- mising subscale 2.61±0.83. The mean score of the Perceived Stress Scale was 13.78±4.74. The mean score for the per- ceived stress subdimension was 4.49±2.04, and for the perceived coping subdimension was 9.30±3.45. A statistically significant, weak positive correlation was found between the perceived stress subdimension and the dominating sub- scale, while a weak negative correlation was observed with the compromising and integration subdimensions. A weak negative correlation was also found between the perceived coping subdimension and the integration, obliging, and compromising subdimensions. Conclusion: According to the nurses, their managers most frequently use obliging, avoiding, dominating, compro- mising, and integration styles, respectively, in conflict management. As managers’ use of compromising and integra- tion styles increases, the nurses’ perceived stress levels decrease.Emerging Sources Citation Inde
Dynamic Instability Analysis of Piezoelectric Nanoplates Under Combined AC/DC Voltages
No full textThis work is devoted to the severe and still unsolved problem of a complete study of the instability of piezoelectric nanoplates under the combined impact of direct current (DC) and alternating current (AC) voltages, nonlocal piezoelastic dependencies, and interaction with an elastic foundation. These combined investigations are rarely discussed in the literature, although they are crucial to the successful functioning of nanoelectromechanical systems (NEMS), such as sensors, actuators, and energy harvesters. To address this research gap, we build a unified theoretical model, founded on Hamilton's principle, Mindlin plate theory, and Eringen nonlocal elasticity theory. Discretization of the governing equations is performed using the Galerkin method, with Floquet theory employed to rigorously identify parametric resonance effects and determine the stability and unstable regions of the voltage-frequency parameter space. The impact of controlling physical parameters, such as nonlocal scale factors, geometric dimensions, magnitude of DC voltage, and elastic foundation stiffness, is systematically studied to explain their collective contributions to instabilities. Our findings indicate that a nonlocal effect, combined with large lateral dimensions, tends to cause instability, whereas a stiff substrate and negative DC voltage enhance stability. Numerical simulations confirm the theory by showing uninhibited transverse displacement in vicinity of resonance regions. This detailed investigation not only contributes to the basic knowledge of electromechanical coupling and dynamics in piezoelectric nanoplates but also provides practical design guidelines to maximize the robustness and efficiency of NEMS devices in the future.Emerging Sources Citation Inde
An Inventory Model with Price-, Time- and Greenness-Sensitive Demand and Trade Credit-Based Economic Communications
No full textMondal, Sankar Prasad/0000-0003-4690-2598;Background: Price is the most authoritative constituent among the factors shaping consumer demand. Growing consciousness among global communities regarding environmental issues makes greenness one of the key factors controlling demand, along with time, which drives demand in markets. This paper addresses such issues associated with a retail purchase scenario. Methods: Consumer's demand for products is hypothesized to be influenced by pricing, time and the green level of the product in the proposed model. Time-dependent inventory carrying cost and green level-induced purchasing cost are considered. The average cost during the decision cycle is the objective function that is analyzed in trade credit phenomena, involving delayed payment by the manufacturer to the supplier. The Convex optimization technique is used to find an optimal solution for the model. Results: Once a local optimal solution is found, sensitivity analysis is conducted to determine the optimal value of the objective function and decision variables for other impacting parameters. Results reveal that demand-boosting parameters, for instance, discounts on price and green activity, result in additional average costs. Conclusions: Discounts on price and green activity advocate a large supply capacity by boosting demand, creating opportunities for the retailer to earn more revenue.Emerging Sources Citation Inde
Üniversite Öğrenci Temsilcilerinin Algıladığı Ebeveyn Tutumları ve Dönüşümcü Liderlik Özelliklerinin İncelenmesi
No full textBu araştırmanın amacı, vakıf üniversitelerinde öğrenim gören öğrenci temsilcilerinin algıladıkları ebeveyn tutumları ile dönüşümcü liderlik özellikleri arasındaki ilişkiyi incelemektir. Araştırma, nitel araştırma desenlerinden olgubilim (fenomenoloji) yöntemi ile yürütülmüştür. Çalışma grubunu, İstanbul ili Tuzla ilçesinde bulunan vakıf üniversitelerinde öğrenim gören ve üniversite öğrencisi temsilcisi olarak görev yapan 15 öğrenci oluşturmaktadır. Katılımcılar amaçlı örnekleme yönteminin bir alt türü olan maksimum çeşitlilik örnekleme yöntemiyle seçilmiştir. Veriler, yarı yapılandırılmış görüşme formu aracılığıyla toplanmış ve betimsel analiz yöntemi ile analiz edilmiştir. Araştırmada, öğrenci temsilcilerinin dönüşümcü liderlik özellikleri ile geçmişte deneyimlediği ebeveyn tutumları arasında belirli bir etkileşim olduğu gözlenmiştir. Katılımcıların büyük çoğunluğunun, demokratik ve destekleyici ebeveyn tutumlarını deneyimledikleri ve bu durumun onların liderlik tarzlarına olumlu yönde yansıdığı belirlenmiştir. Araştırma sonuçları, dönüşümcü liderlik özelliklerinin gelişiminde erken dönem aile tutumlarının etkili olabileceğini göstermektedir. Bu bağlamda çalışma, dönüşümcü liderlik gelişimi açısından ebeveyn tutumlarının rolüne dikkat çekmekte ve üniversitelerde liderlik eğitimi süreçlerinde bu boyutun da göz önünde bulundurulmasını önermektedir
A Stochastic Neural Network Procedure for the Nonlinear Typhoid Fever Disease System
No full textThe aim of this work is to provide the numerical results of the typhoid fever disease system by applying an artificial neural network. The nonlinear typhoid fever disease system is considered into susceptible, exposed, infected, and recovered. The typhoid fever disease system is one of the nonlinear models and numerical results of the system are accomplished via stochastic computing scheme. The optimization is performed by using the Levenberg-Marquardt backpropagation (LMQBP) neural network for solving the nonlinear typhoid fever disease system. An explicit Runge-Kutta solver implemented to calculate the dataset, which is used to lessen the mean square error by data separating into testing (10%), training (70%), and validation (20%). The proposed stochastic scheme is implemented by taking sixteen neurons, log-sigmoid transfer function in the hidden layer, with the input and output layer structure for solving the typhoid fever disease system. The exactness of the scheme is validated by applying the assessment of reference and obtained outputs along with negligible values of the absolute error. Furthermore, the statistical presentations using various disciplines are implemented to indorse the approach's consistency. The proposed stochastic scheme is implemented first time to solve the nonlinear typhoid fever disease system.Emerging Sources Citation Inde
Assessing the Effectiveness and Policy Gaps of Turkish Government Policies in Facilitating Affordable Housing
No full textThis study looks into the impact of government policies on housing affordability in Turkey, specifically how these policies affect the construction industry's ability to provide cheap housing. The study used a qualitative methodology, conducting in-depth interviews with 25 professionals from diverse construction organizations. The attendees comprised architects, civil engineers, and other industry stakeholders from mostly medium-sized businesses in Istanbul and other Turkish cities. Thematic analysis of the interview data yielded noteworthy insights. First, respondents universally observed little to no policy influence in supporting affordable housing or recycled material usage, highlighting a crucial policy gap. Bureaucratic delays, high loan interest rates, and restricted market availability for recycled materials were identified as the key barriers. However, there are potential to raise awareness among clients and industry stakeholders, incorporate affordable techniques into legislation, and build public–private partnerships to improve collaboration. The findings reveal that industry professionals have a largely negative impression of present government policies, further citing expensive plot costs, and tight regulations as major hurdles to affordable housing creation. Furthermore, while some respondents cited collaboration with government agencies and the use of recycled materials as potential solutions, the overall tone indicated a lack of effective government incentives and support. This study emphasizes the need for comprehensive policy reforms to improve stakeholder collaboration and to offer incentives that would reduce building costs and promote the use of sustainable materials. Policy implications include those targeted subsidies, improved administrative processes, and strengthened public-private partnerships are required to create a more favorable climate for affordable home creation in Turkey. © 2025 Elsevier B.V., All rights reserved