Sema Bayraktar

Dr. Sema Bayraktar

Kocaeli University, Kocaeli, Turkey (Türkiye)
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 January 2020 in TURKISH JOURNAL OF MATHEMATICS
Verified
Journal Article
Closed access
Sema BayraktarSema Bayraktar
Sema Bayraktar
ŞGŞevket Gür
Şevket Gür

7 July 2026 in Nutrients
Verified
Journal Article
Open access
PDF file
Jean Chrinot VelombeJean Chrinot Velombe
Jean Chrinot Velombe
Sema BayraktarSema Bayraktar
Sema Bayraktar
AKAdnan Kavak
Adnan Kavak
Muhammad JamilMuhammad Jamil
Muhammad Jamil
Alpaslan Burak İNNERAlpaslan Burak İNNER
Alpaslan Burak İNNER
Hossein FotouhiHossein Fotouhi
Hossein Fotouhi
Background/Objectives: Accurate estimation of meal composition from food images can support safer and more reliable insulin bolus decision-making for individuals with Type 1 diabetes. Existing food recognition and nutrition estimation systems are often designed for general dietary logging and do not directly integrate food analysis with personalized insulin therapy parameters. Methods: This study presents an image-based nutrition estimation and insulin decision-support module developed within the AI-assisted Diabetes Care (AIDCARE) platform. The proposed system uses a convolutional neural network (CNN) to classify food items from a single meal image, and retrieves reference nutritional values from a food composition database. A separate multimodal large language model (MLLM)-based estimation component is then used to estimate portion size, allowing carbohydrate and nutrient values to be scaled according to the observed serving. Results: A curated food image dataset containing 40 food categories was used to evaluate three CNN architectures: ResNet50, Inception V3, and EfficientNet-B0. EfficientNet-B0 achieved the best classification performance, with 94.91% validation accuracy, 95.55% precision, 94.87% recall, and 94.90% F1-score. The portion-estimation component achieved an MAE of 12.27 g and an RMSE of 15.11 g. The estimated carbohydrate value is combined with user-specific clinical parameters, including the insulin-to-carbohydrate ratio and insulin sensitivity factor, to generate advisory bolus guidance. To support safety, the system requires user confirmation or correction of the recognized food category and estimated portion before insulin guidance is displayed. Conclusions: The proposed system is intended for advisory decision support only and is not designed to replace clinical judgment or autonomous insulin delivery systems.

27 July 2026 in Nutrients
Verified
Journal Article
Open access
PDF file
FGFurkan Göz
Furkan Göz
Muhammad JamilMuhammad Jamil
Muhammad Jamil
AKAdnan Kavak
Adnan Kavak
Sema BayraktarSema Bayraktar
Sema Bayraktar
Ali Can Can DoğruAli Can Can Doğru
Ali Can Can Doğru
Hossein FotouhiHossein Fotouhi
Hossein Fotouhi
Background/Objectives: The objective evaluation of regional dietary intake remains a core challenge in personalized health management due to complex plate presentations and a lack of culturally specific dataset benchmarks. Methods: This study introduces a confidence-aware hybrid vision–language framework engineered for traditional Turkish food recognition and structured nutritional assessment. Results: We curate a balanced dataset containing 14,711 verified images spanning 40 representative Turkish culinary classes to train and evaluate seven deep learning architectures. Among the visual models, EfficientNet V2-L achieved the highest standalone performance with an accuracy of 93.47%, 0.92 macro-precision, 0.92 macro-recall, and a 0.92 F1 score. To overcome visual ambiguity and automate content analysis, a confidence-aware routing strategy escalates uncertain predictions (τ<0.70) or user-rejected classifications to the Google Gemini 2.5 Flash multimodal large language model (MLLM). Conclusions: This hybrid paradigm yields a combined classification accuracy of 95.50% while validating portion weight estimations within a mean absolute error (MAE) of 18.42 g and total energy within 36.75 kcal. Fully realized as a cross-platform Flutter mobile application, the end-to-end pipeline demonstrates localized plate detection, adaptive portion analysis, and structured nutrient tracking, providing a scalable design for consumer-facing digital nutrition platforms.

11 May 2026 in Preprints.org
Verified
Preprint
Open access
PDF file
Jean Chrinot VelombeJean Chrinot Velombe
Jean Chrinot Velombe
Sema BayraktarSema Bayraktar
Sema Bayraktar
AKAdnan Kavak
Adnan Kavak
Muhammad JamilMuhammad Jamil
Muhammad Jamil
Alpaslan Burak İNNERAlpaslan Burak İNNER
Alpaslan Burak İNNER
Hossein FotouhiHossein Fotouhi
Hossein Fotouhi
Accurate estimation of meal composition from food images can support safer and more reliable insulin bolus decision-making for individuals with Type 1 diabetes. Existing food recognition and nutrition estimation systems are often designed for general dietary logging and do not directly integrate food analysis with personalized insulin therapy parameters. This study presents an image-based nutrition estimation and insulin decision-support module developed within the AI-assisted Diabetes Care (AIDCARE) platform. The proposed system uses a convolutional neural network (CNN) to classify food items from a single meal image and retrieves reference nutritional values from a food composition database. A separate multimodal large language model (MLLM)-based estimation component is then used to estimate portion size, allowing carbohydrate and nutrient values to be scaled according to the observed serving. A curated food image dataset containing 40 food categories was used to evaluate three CNN architectures: ResNet50, Inception V3, and EfficientNet-B0. EfficientNet-B0 achieved the best classification performance, with 94.91% validation accuracy, 95.55% precision, 94.87% recall, and 94.90% F1-score. The portion-estimation component achieved an MAE of 12.27 g and an RMSE of 15.11 g. The estimated carbohydrate value is combined with user-specific clinical parameters, including the insulin-to-carbohydrate ratio and insulin sensitivity factor, to generate advisory bolus guidance. To support safety, the system requires user confirmation or correction of the recognized food category and estimated portion before insulin guidance is displayed. The proposed system is intended for advisory decision support only and is not designed to replace clinical judgment or autonomous insulin delivery systems.

9 September 2026 in Engineering Proceedings
Verified
Conference Paper
Open access
PDF file
Sema BayraktarSema Bayraktar
Sema Bayraktar
AKAdnan Kavak
Adnan Kavak
Muhammad JamilMuhammad Jamil
Muhammad Jamil
ADAli Can Doğru
Ali Can Doğru
Muhammad FarhanMuhammad Farhan
Muhammad Farhan
GAGünay Aslan
Günay Aslan
Next-generation Intelligent Transportation Systems (ITSs) require ultra-reliable, low-latency Vehicle-to-Everything (V2X) communication frameworks that support safety-critical vehicular services. Conventional centralized, monolithic architectures suffer from excessive transmission latency, limited scalability, and authentication overheads that are ill-suited to the highly dynamic and dense vehicular environment. This paper presents a secure and low-latency edge–cloud architecture for intelligent V2X communications based on a lightweight microservice-driven design paradigm. A formal latency-constrained model is presented to ensure that the end-to-end delay satisfies tight real-time constraints. The proposed framework is lightweight and includes HMAC-based authentication, nonce-based replay protection, timestamp validation, and short-lived encrypted session tokens in a stateless architecture using the Laravel framework deployed at the edge layer. Security validation is performed at edge gateways, and asynchronous SQLite-backed job queues support non-blocking telemetry processing and scalable service orchestration. Experimental evaluation shows that the edge-based deployment achieves a mean response time of 2.58 ms with small variance under repeated request conditions, while centralized processing exhibits significantly higher latency. The results demonstrate that secure authentication and telemetry exchange can be achieved without breaching strict latency requirements. The proposed solution creates a deployable, scalable, and security-aware foundation for next-generation V2X ecosystems and Intelligent Transportation Systems (ITSs) in real time.

1 January 2025 in Sigma Journal of Engineering and Natural Sciences
Verified
Journal Article
Open access
PDF file
Sema BayraktarSema Bayraktar
Sema Bayraktar
EÇEmine Çeli̇k
Emine Çeli̇k
ŞGŞevket Gür
Şevket Gür
We consider an initial-boundary value problem for a fourth-order nonlinear parabolic equation with constant coefficients. Our primary focus lies in establishing a priori estimates for the solution to this equation, with a particular emphasis on its continuous dependence on both the initial data and parameters. Using energy estimates, we establish the continuous dependency for both the solution and its gradient concerning the fourth-order nonlinear parabolic equation.