检索结果-南通市图书馆

A robust optimization method for label noisy datasets based on adaptive threshold: Adaptive-k

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第4期18卷 49-60页

作者： Enes DEDEOGLU Himmet Toprak KESGIN mehmet fatih AMASYALI Department of Computer Engineering Yildiz Technical UniversityIstanbul 34220Turkey

The use of all samples in the optimization process does not produce robust results in datasets with label *** the gradients calculated according to the losses of the noisy samples cause the optimization process to go in the wrong *** this paper,we recommend using samples with loss less than a threshold determined during the optimization,instead of using all samples in the *** proposed method,Adaptive-k,aims to exclude label noise samples from the optimization process and make the process *** noisy datasets,we found that using a threshold-based approach,such as Adaptive-k,produces better results than using all samples or a fixed number of low-loss samples in the *** the basis of our theoretical analysis and experimental results,we show that the Adaptive-k method is closest to the performance of the Oracle,in which noisy samples are entirely removed from the ***-k is a simple but effective *** does not require prior knowledge of the noise ratio of the dataset,does not require additional model training,and does not increase training time *** the experiments,we also show that Adaptive-k is compatible with different optimizers such as SGD,SGDM,and *** code for Adaptive-k is available at GitHub.

关键词： robust optimization label noise noisy label deep learning noisy datasets noise ratio estimation robust training

Wear and mechanical properties of carburized AISI 8620 steel produced by powder metallurgy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 430-439页

作者： mehmet Akif Erden fatih Aydın Department of Biomedical Engineering Karabuk UniversityKarabuk 78050Turkey Department of Metallurgical and Materials Engineering Karabuk UniversityKarabuk 78050Turkey

The effect of carburization on the tensile strength and wear resistance of AISI 8620 steel produced via powder metallurgy was *** 1 and 2(with 0.2wt%C and 0.25wt%C,respectively)were first pressed at 700 MPa and then sintered at 1300,1400,or 1500℃for 1 *** ideal sintering temperature of 1400℃was ***,Alloys 1 and 2 sintered at 1400℃were carburized at 925℃for 4 *** microstructure characterization of alloys was performed via optical microscopy and scanning electron *** mechanical and wear behavior of carburized and noncarburized alloys were investigated via hardness,tensile,and wear *** carburization,the ultimate tensile strength of Alloys 1 and 2 increased to 134.4%and 138.1%,***,the elongation rate of Alloys 1 and 2 decreased to 62.6%and 64.7%,*** wear depth values of Alloy 2 under noncarburized and carburized conditions and a load of 30 N were 231.2 and 100.1μm,*** wear changed to abrasive wear when the load transitioned from 15 to 30 N.

关键词： powder metallurgy steels carburization microstructure wear mechanical properties

A New Reward System Based on Human Demonstrations for Hard Exploration Games

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第2期70卷 2401-2414页

作者： Wadhah Zeyad Tareq mehmet fatih Amasyali Faculty of Electrical and Electronics Engineering Yildiz Technical UniversityIstanbul34220Turkey

The main idea of reinforcement learning is evaluating the chosen action depending on the current *** to this concept,many algorithms achieved proper performance on classic Atari 2600 *** main challenge is when the reward is sparse or *** environments are complex exploration environments likeMontezuma’s Revenge,Pitfall,and Private Eye *** built to deal with such challenges were very *** work introduced a different reward system that enables the simple classical algorithm to learn fast and achieve high performance in hard exploration ***,we added some simple enhancements to several hyperparameters,such as the number of actions and the sampling ratio that helped improve *** include the extra reward within the human *** that,we used Prioritized Double Deep Q-Networks(Prioritized DDQN)to learning from these *** approach enabled the Prioritized DDQNwith a short learning time to finish the first level of Montezuma’s Revenge game and to perform well in both Pitfall and Private *** used the same games to compare our results with several baselines,such as the Rainbow and Deep Q-learning from demonstrations(DQfD)*** results showed that the new rewards system enabled Prioritized DDQN to out-perform the baselines in the hard exploration games with short learning time.

关键词： Deep reinforcement learning human demonstrations prioritized double deep q-networks atari

Treatment of retinopathy of prematurity: a review of conventional and promising new therapeutic options

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2013年第2期6卷 228-236页

作者： fatih mehmet Mutlu Umit Serdar Sarici Department of Ophthalmology Gülhane Military Medical Academy and Medical School Department of Pediatrics Division of Neonatology Gülhane Military Medical Academy and Medical School

Retinopathy of prematurity (ROP), a retinal vascular disease of premature infants, continues to be a major cause of preventable childhood blindness all over the world. The incidence of ROP varies among countries, being influenced by the quality of the level of neonatal intensive care. Here, we discuss the potential treatments that are now available or will soon or probably be available for ROP. Although ablation of the avascular retina with laser photocoagulation remains the current gold standard and well established therapy for ROP, some new therapeutic options including angiostatic therapies are being explored based on our knowledge of the pathophysiology of the ROP and complications and efficacy of laser treatment. However, prevention of the development of severe ROP and screening for ROP seem to be the best strategy in avoiding visual impairment caused by ROP in premature infants. New therapeutic interventions including vascular endothelial growth factor antibody administration, gene therapy and supplemental therapies should be supported with evidence-based data for the treatment of ROP.

关键词： retinopathy of prematurity laser retina vascular endothelial growth factor propranolol

A comparative analysis of text representation, classification and clustering methods over real project proposals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Intelligent Computing and Cybernetics 2023年第3期16卷 595-628页

作者： Meltem Aksoy Seda Yanık mehmet fatih Amasyali Industrial Engineering Department Istanbul Technical UniversityIstanbulTurkey Computer Engineering Department Yıldız Technical UniversityIstanbulTurkey

Purpose-When a large number of project proposals are evaluated to alocate available funds,grouping them based on their simiarites is *** approaches to group proposals are primarily based on manual matching of similar topics,discipline areas and keywordls declared by project *** the number of proposals increases,this task becomes complex and requires excessive *** paper aims to demonstrate how to ffctively use the rich information in the titles and abstracts of Turkish project propsals to group them ***/methodology/approach-This study proposes a model that effectively groups Turkish project proposals by combining word embedding,clustering and classification *** proposed model uses FastText,BERT and term frequency/inverse document frequency(TF/IDF)word-embedding techniques to extract terms from the titles and abstracts of project proposals in *** extracted terms were grouped using both the clustering and classification *** groups contained within the corpus were discovered using k-means,k-means++,k-medoids and agglomerative clustering algorithms,Additionally,this study employs classification approaches to predict the target class for each document in the *** classify project proposals,var ious classifiers,including k nearest neighbors(KNN),support vector machines(SVM),artificial neural networks(ANN),cassftcation and regression trees(CART)and random forest(RF),are *** experiments were conducted to validate the effectiveness of the proposed method by using real data from the Istanbul Development ***-The results show that the generated word embeddings an fftvely represent proposal texts as vectors,and can be used as inputs for dustering or casificatiomn *** clustering algorithms,the document corpus is divided into five *** adition,the results demonstrate that the proposals can easily be categoried into predefmned categories using cassifiation alg

关键词： Project proposal selection Text mining Word embedding Text clustering Text classification

Determining Crop and Pan Coefficients for Cauliflower and Red Cabbage Crops Under Cool Season Semiarid Climatic Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2009年第2期8卷 167-171页

作者： Ustun Sahin Yasemin Kuslu Talip Tunc fatih mehmet Kiziloglu Department of Agricultural Structures and Irrigation Faculty of Agriculture Atatürk University

The aim of this study was to estimate the evapotranspiration of cauliflower and red cabbage crops grown under cool season semiarid climatic conditions from Class A pan evaporation. Actual evapotranspiration （ETc） of cauliflower and red cabbage crops was calculated according to the water balance approach. Reference evapotranspiration （ETo） was calculated with FAO Penman-Monteith equation. Pan evaporation （Epan） was measured by using Class A pan. Seasonal ETc was determined as 475 mm for cauliflower and 556 nun for red cabbage. Seasonal pan coefficient （kp=ETo/Epan） was determined as 0.82, and the seasonal crop coefficient （kc=ETc/ETo） was determined as 0.84 for cauliflower and 0.83 for red cabbage. So the evapotranspiration of cauliflower and red cabbage crops was estimated as 70% Class A pan evaporation.

关键词： crop coefficient (kc) evapotranspiration pan coefficient (kp)

Atrial electromechanical coupling parameters after transcatheter aortic valve replacement

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2016年第6期13卷 557-558页

作者： mehmet Dogan Omer Yiginer fatih Ozcelik Alptug Tokatli Department of Cardiology Ankara Mevki Military Hospital Turkey Department of Cardiology Gulhane Military Medical Academy Haydarpasa Training Hospital Turkey Department of Biochemistry Gulhane Military Medical Academy Haydarpasa Training Hospital Turkey Department of Cardiology Golcuk Military Hospital Turkey

The article entitled Effect of transcatheter aortic valve replacement on P-wave duration, P-wave dispersion and left atrial size by Dursun, et al. has contributed to our knowledge regarding the positive effects of transcatheter aortic valve replacement （TAVR） procedure on atrial electrical remodeling. In this study, TAVR procedure led to a decrease on P-wave duration and P-wave dinner,inn

关键词： Atrial fibrillation Electromechanical coupling, P-wave dispersion Transcatheter aortic valve replacement

Clinical efficacy and drug resistance of anti-epidermal growth factor receptor therapy in colorectal cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2016年第1期8卷 1-7页

作者： hakan kocoglu fatih mehmet velibeyoglu mustafa karaca deniz tural department of medical oncology bakirkoy education and research hospital34900 IstanbulTurkey department of medical oncology gazi university faculty of medicine06500 AnkaraTurkey

Colorectal cancer(CRC) ranked third in cancer related death and its incidence has been increasing worldwide. In recent decades important therapeutic advances have been developed in treatment of metastatic CRC(mCRC), such as monoclonal antibodies against epidermal growth factor receptor(anti-EGFR), which provided additional clinical benefits in mCRC. However, anti-EGFR therapies have limited usage due to approximately 95% of patients with KRAS mutated mCRC do not response to anti-EGFR treatment. Thus, KRAS mutation is predictive of nonresponse to anti-EGFR therapies but it alone is not a sufficient basis to decide who should not be received such therapies because; approximately fifty percent(40%-60%) of CRC patients with wild-type KRAS mutation also have poor response to anti-EGFR based treatment. This fact leads us to suspect that there must be other molecular determinants of response to anti-EGFR therapies which have not been identified yet. Current article summarizes the clinical efficacy of anti-EGFR therapies and also evaluates its resistance mechanisms.

关键词： Colorectal cancer Epidermal growth factorreceptor KRAS mutation Anti-epidermal growth factorreceptor antibody Drug resistance

Efficacy of the subthreshold micropulse yellow wavelength laser photostimulation in the treatment of chronic central serous chorioretinopathy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2020年第9期13卷 1404-1410页

作者： Mehmed Ugur Isιk mehmet fatih Kagan Degirmenci Ayhan Saglιk Department of Ophthalmology Kastamonu University Faculty of MedicineKastamonu 37100Turkey Department of Ophthalmology CanklrlState HospitalCankin 18800Turkey Department of Ophthalmology Harran University Faculty of MedicineSanllurfa 63000Turkey

AIM:To evaluate the efficacy and safety of subthreshold micropulse yellow laser(SMYL)in the treatment of chronic central serous chorioretinopathy(CCSC).METHODS:The medical records of 58 eyes of 58 patients with CCSC were reviewed.A 577-nm SMYL system was used for the *** fluorescein angiography was used as the primary method of identifying CCSC,and resolution of subretinal fluid(SRF)evaluated by optical coherence tomography(OCT)and fundus *** macular thickness(CMT),central macular volume(CMV),total macular volume(TMV),subfoveal choroidal thickness(SFCT),subretinal fluid height(SRFH),and subfoveal fluid basement diameter values were measured by spectral domain-OCT(SD-OCT)for all ***:The mean age of the patients was 42.4±9.9(range:20-72)*** mean follow-up was 11.4±8.5(range:6-37)*** BCVA at at the final follow up after treatment was statistically significant from the *** SRF resolution was 12.1%of the eyes in the 1^st month,67.2%of the eyes in the 3rd month and 67.2%of the eyes in the last follow *** initial median CMT,CMV,TMV,and SFCT values before treatment was significantly higher than 3^rd month visit values(P<0.001).In the multivariate analysis performed,age and disease duration were found to be a risk factor for persistent SRF(P=0.017,P=0.016,respectively).CONCLUSION:SMYL treatment provides a significant anatomical and functional improvement and is effective in eliminating SRF in eyes with CCSC.

关键词： central serous chorioretinopathy subthreshold micropulse laser optical coherence tomography