15 research outputs found
Meme Kanserli Olgularda Adjuvan Radyoterapinin Tiroid Fonksiyonları Üzerine Etkisi
Amaç: Meme kanseri görülme sıklığı yıllar içerisinde artmasına rağmen meme kanserine bağlı ölüm oranlarında belirgin azalma dikkat çekmektedir. Buna bağlı olarak artan genel sağkalım süreleri, meme kanseri tedavisinde görülen yan etkilerin önemini arttırmıştır. Bu çalışmada meme kanseri nedeniyle adjuvan radyoterapi RT uygulanan olgularda, RT’nin tiroid fonksiyonlarına etkisinin değerlendirilmesi amaçlanmıştır.Gereç ve Yöntem: Bölümümüzde 2009-2017 yılları arasında meme kanseri nedeniyle RT uygulanmış 87 hastanın demografik verileri, tümör evreleri, tedavi modaliteleri, tiroid hacimleri, tedavi öncesi ve sonrası TSH, T3 ve T4 değerleri, RT doz ve hacimleri ile tiroid bezinin doz-volüm değerleri hasta dosyaları, planlama sistemi ve Gazi Üniversitesi Tıp Fakültesi elektronik veritabanından toplanarak değerlendirildi.Veriler SPSS 22.0 dosyasına aktarılarak hipotiroidizm ile RT doz-hacim, tiroid hacmi ilişkisi ki-kare ve parametrik olmayan testlerle analiz edildi.Bulgular: Medyan yaş 50 idi. 87 hastanın 85’i kadın %98 , 2 tanesi erkekti %2 . 59 hastanın metastatik lenf nodu %59 mevcuttu. 53 hastada %61 supraklaviküler alan SKF tedavi hacmi içerisindeydi. Toplamda 12 hastada 14% RT’ye bağlı hipotiroidizm görüldü. Lenf nodu pozitifliği, ve buna bağlı olarak yapılan SKF ışınlaması hipotiroidizm gelişmesi ile anlamlı olarak ilişkili saptandı sırasıyla p=0.013, p=0.003 . Çok değişkenli analizde sadece ortalama doz Dort=24Gy ve V30 %30 değerleri hipotiroidizm gelişmesi açısından istatistiksel olarak anlamlı bulundu sırasıyla p=0.038, p=0.044 . V30 değerlerinin >%30 olduğu olgularda hipotirodizm gelişme riskinin daha yüksek olduğu gözlendi
Elektrik empedans spektroskopi meme doku kayıtlarının sınıflandırılmasında topluluk algoritmalarının başarısı
Eroğlu, Kübra (Arel Author) --- 2014 22nd Signal Processing and Communications Applications Conference, SIU 2014 -- 23 April 2014 through 25 April 2014 -- TrabzonIn this study was performed by using records from breast tissue electrical impedance spectroscopy analysis. The aim of the study is to reveal the impact of ensemble algorithms on success of the classification performance in the classification of normal and pathological breast tissue classification. For this purpose have been used three different ensemble algorithms they are bagging, adaboost, random subspaces and three main basic classifiers, which are RF, YSA, DVM. The results obtained are supplemented with performance analysis and ensemble algorithms have been demonstrated to increase classification performance results. The results obtained by the combined use of adaboost ensemble algorithm with RF basic classifier demonstrate, that the success rate was higher than the others (%89.62). © 2014 IEEE
Investigation of a laterally loaded model pile behaviour in sand by means of experimental and numerical methods
Niyazi Uğur TERZİ (Aksaray Üniversitesi yazarı)Bu çalışmada, farklı kum ortamlarında yerleştirilmiş olan bir kazık modelinin yanal yüklemeler altındaki gerilme-şekil değiştime ve yerdeğiştirme davranışı incelenmiştir. Labaratuvar ortamında yürütülen çalışmada, dairesel bir alüminyum kazık, deney kutusu, yükleme düzeneği, yer değişimi ve şekil değişimi ölçerler kullanılmıştır. Yağmurlama sistemi kullanılarak eşdeğer sıkılık ve homojen bir dolgu ortamı oluşturulmuştur. Deneysel çalışmalarda model kazığın kademeli yüklemeler altındaki gösterdiği davranışı deneysel olarak saptanmıştır ve daha sonra kazık davranışı, tasarımcılar tarafından yaygın olarak kullanılan p-y ve yatak katsayısı yöntemleri kullanılarak analiz edilmiştir. Nümerik çalışmalar LPILE ve SAP 2000 programlarında gerçekleştirilmiştir. Yapılan çalışmalar sonucunda, p-y yönteminin yatak katsayısı yönteminden daha güvenilir sonuçlar ortaya koyduğu saptanmıştır. Kumun sıkılık derecesinin zemin reaksiyonu üzerindeki etkisi görülmüştür. Son olarak ölçüm aygıtlarının kalibrasyonunda kullanılan Daley yönteminin güvenilir olduğu anlaşılmıştır.In this study, stress-strain relation and deformation behavior of laterally loaded pile which is located in different sand embedment is investigated. A circular aluminum pile, test box, loading system, strain gauge rosettes and linear position transducers were used in the laboratory test. Uniform relative density and homogeneous embedment medium in the test box were achieved by using sand pluviation system. The behavior of aluminum pile loaded incrementally at its head is obtained experimentally and then p-y method and subgrade reaction method which is commonly used by designers are employed to model the numerical behavior of the pile. Numerical studies were performed by using LPILE and SAP 2000 computer programs. Based on the findings, the p-y method estimates the pile head deflection more accurately than subgrade reaction method particularly high lateral deflections of pile head. The experimental test studies show that relative density of sand embedment is very effective on occurrence of soil reaction. Finally the reliability of Daley calibration method which is used in instrumentation was evaluated
Colon segmentation and colonic polyp detection using cellular neural networks and three-dimensional template matching
Osman, Onur (Arel Author)In this study, an automatic three-dimensional computer-aided detection system for colonic polyps was developed. Computer-aided detection for computed tomography colonography aims at facilitating the detection of colonic polyps. First, the colon regions of whole computed tomography images were carefully segmented to reduce computational burden and prevent false positive detection. In this process, the colon regions were extracted by using a cellular neural network and then the regions of interest were determined. In order to improve the segmentation performance of the study, weights in the cellular neural network were calculated by three heuristic optimization techniques, namely genetic algorithm, differential evaluation and artificial immune system. Afterwards, a three-dimensional polyp template model was constructed to detect polyps on the segmented regions of interest. At the end of the template matching process, the volumes geometrically similar to the template were emhanced
Osmanlıca Karakterlerin Yapay Sinir Ağları ile Tanınması ve Türkçeye Çeviren Akıllı Bir Sistemin Geliştirilmesi”
Breast Cancer Detection with Reduced Feature Set
This paper explores feature reduction properties of independent component analysis (ICA) on breast cancer decision support system. Wisconsin diagnostic breast cancer (WDBC) dataset is reduced to one-dimensional feature vector computing an independent component (IC). The original data with 30 features and reduced one feature (IC) are used to evaluate diagnostic accuracy of the classifiers such as k-nearest neighbor (k-NN), artificial neural network (ANN), radial basis function neural network (RBFNN), and support vector machine (SVM). The comparison of the proposed classification using the IC with original feature set is also tested on different validation (5/10-fold cross-validations) and partitioning (20%–40%) methods. These classifiers are evaluated how to effectively categorize tumors as benign and malignant in terms of specificity, sensitivity, accuracy, F-score, Youden’s index, discriminant power, and the receiver operating characteristic (ROC) curve with its criterion values including area under curve (AUC) and 95% confidential interval (CI). This represents an improvement in diagnostic decision support system, while reducing computational complexity
Experimental investigations of backfill conditions on the performance of high-density polyethelene pipes
WOS: 000301574000007In this study, a series of laboratory tests on 100-mm-diameter high-density polyethylene (HDPE) 100 PE flexible pipe buried in poorly graded Sile quartz sand with different relative densities are described. The laboratory tests were performed in a 40-mm-thick plexiglass fronted test tank that replicated a classical trench section in field conditions. The HDPE flexible pipe was positioned against the glass with its longitudinal axis perpendicular to the glass. This allowed direct observation of the backfillpipe interactions. Three high-definition photogrammetric cameras were used to capture the photogrammetric images through the glass allowing the discrete measurement and image processing of the deformation patterns of the pipe conduit during the pipe installation and incremental surcharge loading. Vertical loads were applied in increments of 10150 kPa using air pressure membranes. Electric resistant strain gauges measured the bending moments of the pipe walls under vertical surcharge loadings. For each loading step, the vertical deformation of the pipe crown was also measured using linear position transducers. According to the test results, it is understood that the installation technique and backfill relative density have an important effect on circumferential strains, performance, and deformation characteristics of HDPE pipes. It was also observed that close-range image processing is a very simple and appropriate method for measuring three-dimensional pipe deformations under various conditions.TUBITAK [104I107]This study is supported by the TUBITAK 104I107 project