Fazli Yildirim

Prof. Dr. Fazli Yildirim

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

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

Representative Publications

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7 November 2025 in Diagnostics
Verified
Journal Article
Open access
PDF file
MCMehmet akif Cifci
Mehmet akif Cifci
Batuhan ÖNEYBatuhan ÖNEY
Batuhan ÖNEY
FYFazli Yildirim
Fazli Yildirim
HBHülya YILMAZ BAŞER
Hülya YILMAZ BAŞER
MZMetin Zontul
Metin Zontul
Background: This study introduces the Adaptive Graph Fusion Network, an interpretable graph-based learning framework developed for large-scale prediction of intensive care outcomes. The proposed model dynamically constructs patient similarity networks through a density-aware kernel that adjusts neighborhood size based on local data distribution, thereby representing both frequent and rare clinical patterns. Methods: To characterize physiological evolution over time, the framework integrates a short-horizon convolutional encoder that captures acute variations in vital signs and laboratory results with a long-horizon recurrent memory unit that models gradual temporal trends. The approach was trained and internally validated on the publicly available eICU Collaborative Research Database, which includes more than 200,000 admissions from 208 hospitals across the United States. Results: The model achieved a mean area under the receiver operating characteristic curve of 0.91 across six critical outcomes, with in-hospital mortality reaching 0.96, outperforming logistic regression, temporal long short-term memory networks, and calibrated Transformer-based architectures. Feature attribution analysis using SHAP and temporal contribution mapping identified lactate trajectories, creatinine fluctuations, and vasopressor administration as dominant determinants of risk, consistent with established clinical understanding while revealing additional temporal dependencies overlooked by existing scoring systems. Conclusions: These findings demonstrate that adaptive graph construction combined with multi-horizon temporal reasoning improves predictive reliability and interpretability in heterogeneous intensive care populations, offering a transparent and reproducible foundation for future research in clinical machine learning.

7 April 2026 in Agronomy
Verified
Journal Article
Open access
PDF file
TKTolga Karaköy
Tolga Karaköy
IYIlkay Yelmen
Ilkay Yelmen
MZMetin Zontul
Metin Zontul
FYFazli Yildirim
Fazli Yildirim
Chickpea (Cicer arietinum L.) is a globally important legume crop whose grain yield is strongly influenced by environmental and agronomic variability. This study aimed to predict chickpea grain yield using artificial neural networks (ANNs) and to identify key traits associated with yield formation across different genotypes under semi-arid conditions. The dataset consisted of 96 chickpea genotypes evaluated over two growing seasons (2022–2023) in Sivas, Türkiye. The results demonstrated that reproductive traits, particularly seed weight per plant, number of pods per plant, and number of seeds per plant, were the most influential factors determining grain yield. Environmental variability also contributed significantly to yield prediction, highlighting the importance of genotype–environment interactions. The developed ANN model showed high predictive accuracy, indicating its robustness in capturing complex relationships among yield-related traits. Beyond prediction, the model provides biologically meaningful insights into trait prioritization, supporting its application in chickpea breeding programs. Overall, the findings suggest that ANN-based approaches can serve as effective decision-support tools in precision agriculture by enabling accurate yield estimation, facilitating the selection of high-performing genotypes, and identifying key breeding traits for sustainable crop improvement.

18 May 2026 in Drones
Verified
Journal Article
Open access
PDF file
Alparslan GuzeyAlparslan Guzey
Alparslan Guzey
Mehmet Akif CifciMehmet Akif Cifci
Mehmet Akif Cifci
FYFazli Yildirim
Fazli Yildirim
Arda Yasar ErdoganArda Yasar Erdogan
Arda Yasar Erdogan
Rapid localisation of trapped victims after urban disasters is essential but challenging because Bluetooth Low Energy (BLE) beacons are intermittent, radio propagation is obstructed by rubble, UAVs are energy-constrained, and real-world multi-UAV training is impractical in high-risk search-and-rescue (SAR) environments. This study formulates post-disaster victim localisation as a cooperative Dec-POMDP and adapts a model-aided federated multi-agent reinforcement learning framework based on FedQMIX. The proposed pipeline combines a lightweight LoS/NLoS surrogate channel model, PSO-based victim-position estimation, return-to-base and map-feasibility safety checks, an SAR-aligned shaped reward, and a leakage-free centralised training state based on estimated rather than ground-truth victim locations. Each UAV trains locally inside a learned digital-twin simulator and periodically shares only QMIX network parameters, avoiding the exchange of raw trajectories or RSSI logs. The framework is evaluated on two synthetic post-earthquake urban maps representing a compact return-to-base scenario and a larger reach-to-destination scenario. Across five independent seeds per method and map, Model-Aided FedQMIX achieves the highest and most stable victim-localisation performance, with the clearest advantage observed in the larger long-horizon scenario. Additional diagnostic tests examine reward-weight sensitivity, RF channel-shift robustness, BLE/smartphone hardware heterogeneity, non-IID client-data variation, and partial-client FedAvg under missing client updates. The results indicate that combining model-aided localisation cues, decentralised value factorisation, SAR-aligned objective design, and federated parameter sharing can improve the robustness of UAV-based victim-localisation policies. The framework also clarifies deployment considerations for federated SAR coordination, including communication payload, privacy boundaries, heterogeneous client experience, device variability, and intermittent connectivity. This study remains simulation-based, and future validation with real UAVs, BLE devices, and rubble-inspired testbeds is required before operational deployment.

30 April 2026 in Diagnostics
Verified
Journal Article
Open access
PDF file
Mehmet Akif CifciMehmet Akif Cifci
Mehmet Akif Cifci
KKKadir Karataş
Kadir Karataş
FYFazli Yildirim
Fazli Yildirim
ADALİ DOĞAN
ALİ DOĞAN
Background/Objectives: Automated brain tumor classification from MRI is particularly challenging when restricted to single post-contrast axial T1-weighted slices without volumetric or clinical context. Methods: We present a four-class (glioma, meningioma, pituitary tumor, no tumor) slice-level classification framework that combines a fine-tuned Swin-Tiny Transformer with inverse-frequency class-weighted learning and a prototype SMT-based symbolic auditing layer for post hoc logical consistency checks. All architectures were trained and evaluated under identical preprocessing, augmentation, optimization, and evaluation protocols. Results: On an internal clinical dataset from Bandırma Onyedi Eylül University Hospital (n = 8040 slices), Swin-Tiny achieved 97.42% slice-level accuracy (macro-F1 97.42%, macro-AUC 0.994), exceeding matched convolutional baselines by approximately eight percentage points. Five-fold stratified cross-validation confirmed stability (mean accuracy 97.40% ± 0.28%). Zero-shot evaluation on the independent BRISC-2025 dataset (n = 6000 slices) yielded 94.82% accuracy and macro-AUC 0.97, indicating maintained performance under acquisition-related distribution shift. Per-class metrics were consistently high across tumor types, with residual errors dominated by glioma–meningioma confusion, reflecting known radiologic overlap on single contrast-enhanced T1 slices. The symbolic auditing layer flagged 1.2–2.9% of predictions as constraint-violating; most such cases were borderline but correctly classified, suggesting sensitivity of heuristic thresholds rather than systematic model failure. Conclusions: These findings support the value of hierarchical shifted-window attention for integrating local texture and broader spatial context in slice-level MRI classification. While patient-wise, multimodal, and prospective validation remain necessary for clinical deployment, this study provides a controlled empirical benchmark and a prototype mechanism for post hoc logical auditing in neuro-oncologic imaging.

3 August 2026 in Information
Verified
Journal Article
Open access
PDF file
Mehmet Akif CifciMehmet Akif Cifci
Mehmet Akif Cifci
YFYousef Farhang
Yousef Farhang
Batuhan ÖNEYBatuhan ÖNEY
Batuhan ÖNEY
ZEZiya Gökalp Ersan
Ziya Gökalp Ersan
FYFazli Yildirim
Fazli Yildirim
UAUğur AKBULUT
Uğur AKBULUT
Water resource management increasingly requires allocation methods that address rising demand, climate variability, and operational inefficiency. This study proposes an elite-transfer hybrid Genetic Algorithm–Particle Swarm Optimization framework for constrained water allocation under a weighted-sum scalarization model. The model combines four normalized objectives: minimizing water shortage, an operational cost coefficient, and allocation imbalance while maximizing utilization efficiency through an equivalent minimization term. A bidirectional elite-transfer mechanism links GA-based global exploration with PSO-based local refinement. The framework was evaluated using two capacity-constrained surrogate scenarios anchored to hydrometeorological records from Türkiye: Melekbahçe station (E21A033) in the Upper Euphrates Basin and Beşdeğirmen station (E12A003) in the Sakarya Basin. Daily streamflow records supported scenario construction, while precipitation and air-temperature data characterized local conditions. The proposed method was compared with standalone GA and standalone PSO, Differential Evolution, Grey Wolf Optimizer, a scalarized NSGA-II, adapted Kao–Zahara and Garg GA–PSO hybrids, and a no-elite ablation. All methods used the same objective formulation, normalization bounds, constraint-repair procedure, equal objective weights, tuning protocol, paired random seeds, and a budget of 10,000 objective-function evaluations. Performance was assessed through 30 paired runs per scenario. The proposed framework achieved the lowest mean scalar fitness values—0.1670 for Melekbahçe and 0.1752 for Beşdeğirmen—and reached the predefined convergence region after averages of 4587 and 4780 evaluations, respectively. All fitness and convergence improvements remained significant after Holm correction. Paired rank-biserial correlations ranged from 0.957 to 1.000 against the seven general comparators and were 0.824 and 0.781 against the no-elite ablation. The findings support the framework under the tested surrogate scenarios but do not establish Pareto-front dominance or universal superiority. Future work should examine measured operational data, additional basins, dynamic scheduling, alternative weights, and Pareto-based extensions.

12 May 2026 in IEEE Access
Verified
Journal Article
Open access
GKGultekin Kocun
Gultekin Kocun
IYIlkay Yelmen
Ilkay Yelmen
MZMetin Zontul
Metin Zontul
FYFazli Yildirim
Fazli Yildirim
Ectopic pregnancy (EP) is a significant cause of maternal morbidity and mortality, particularly in the first trimester. It occurs when a fertilized ovum implants outside the uterine cavity, with the fallopian tubes being the most common location. Early and accurate diagnosis is critical to prevent complications such as tubal rupture and hemorrhage. Traditional diagnostic methods rely on transvaginal ultrasound (TVUS) and serial β-hCG measurements, but these approaches can sometimes yield inconclusive results. Recent progress in artificial intelligence has demonstrated potential for improving the precision of ectopic pregnancy detection. This study examines the use of artificial intelligence-based classification models to predict pregnancy outcomes using routinely available clinical data. The dataset comprises 310 patient records collected from real-world clinical practice. Several classification approaches were evaluated, with particular emphasis on tree-based ensemble models. Experimental results indicate that the LightGBM DART model outperformed the other evaluated classifiers, achieving the highest overall performance with an accuracy of 0.9161, a macro-AUC of 0.9409, and a balanced accuracy of 0.9080, followed by CatBoost and Histogram-based Gradient Boosting models. To enhance model transparency and clinical interpretability, Shapley Additive Explanations (SHAP) were applied to identify the most influential features contributing to model predictions. These findings suggest that explainable artificial intelligence (XAI)-based predictive models may support early and accurate diagnosis during the early follow-up period (Day 0–12), assist clinicians in timely decision-making, and potentially improve patient management, rather than serving as a standalone tool for initial Day-0 triage.