Sınıf Öğretmeni Adaylarının Silindir ve Koniye Yönelik Kavram İmajlarının İncelenmesi

Bu araştırmada sınıf öğretmeni adaylarının silindir ve koniye ilişkin kavram imajlarını ortaya çıkarmak amaçlanmıştır. Bu amaç doğrultusunda öğretmen adaylarının bu geometrik cisimlere ilişkin tanımları ve çizimleri incelenmiştir. Çalışmada nitel araştırma yöntemi kullanılmıştır. Seçkisiz olmayan örnekleme yöntemlerinden biri olan uygun örnekleme yöntemiyle belirlenen 126 sınıf öğretmeni adayına açık uçlu ve çoktan seçmeli toplam 8 sorudan oluşan bir test uygulanmıştır. Veriler analiz edilirken betimsel ve içerik analizi teknikleri kullanılmıştır. Elde edilen sonuçlar öğretmen adaylarının silindir ve koni kavramlarıyla ilgili yeterli bilgiye sahip olmadıklarını göstermektedir. Bunun yanında öğretmen adaylarının imajlarında silindir ve koni ile ilgili daha çok prototip örneklere yer verdikleri belirlenmiştir. Bu durumun kavram yanılgılarına yol açabileceği sonucu ortaya çıkmıştır

Pre-service Elementary Mathematics Teachers’ Views About Geometric Construction

Geometrical reasoning involves three kinds of cognitive process: visualization process, construction process and reasoning process. Although many studies about the visualization and reasoning process in the learning geometry found in the literature, there were a few researches about the geometric construction process. This study investigated 63 pre-service elementary mathematics teachers’ views about geometric construction activities using compass and straightedge from an education faculty in the west Anatolia region of Turkey. Data were obtained from an open-ended questionnaire and teacher’s field notes. Data were analyzed by descriptive method. The result of the study showed that pre-service teachers haven’t encountered with these activities in their past experiences and they have positive views about them. Moreover they think that these activities would help them to learn geometry concepts. In addition, it was determined that pre-service teachers have difficulties both using compass and deciding how to begin to draw.Geometri öğrenme görselleştirme, geometrik inşa ve muhakeme olmak üzere üç bilişsel süreci içermektedir. Bu süreçlerden görselleştirme ve muhakeme süreçlerine yönelik literatürde birçok çalışmaya rastlanmasına karşın geometrik inşa sürecine yönelik çok fazla çalışmaya rastlanmamaktadır. Bu araştırmada Ege bölgesindeki bir devlet üniversitesinin ilköğretim matematik öğretmenliği bölümünde okuyan 63 öğretmen adayının geometrik inşa etkinliklerine yönelik görüşleri incelenmiştir. Bu amaçla veriler açık uçlu sorulardan oluşan bir görüş formu ve dersin öğretmeni tarafından tutulan alan notları yardımıyla toplanmıştır. Elde edilen veriler betimsel olarak analiz edilmiştir. Sonuçlar, öğretmen adaylarının geçmiş deneyimlerinde bu tür inşa etkinlikleriyle çok fazla karşılaşmadıklarını, geometrik inşa etkinliklerine yönelik olumlu düşüncelerinin olduğunu ve bu çalışmaların geometri konularının öğrenilmesine yardımcı olacağını düşündüklerini göstermektedir. Bunun yanında öğretmen adaylarının inşa etkinliklerinde karşılaştıkları en büyük güçlüklerin ise pergel ve ölçüsüz cetveli kullanma ve inşa aşamalarına karar verme oldukları belirlenmiştir

Image information mining using spatial relationship constraints

Ankara : The Department of Computer Engineering and the Graduate School of Engineering and Science of Bilkent University, 2012.Thesis (Master's) -- Bilkent University, 2012.Includes bibliographical refences.There is a huge amount of data which is collected from the Earth observation satellites and they are continuously sending data to Earth receiving stations day by day. Therefore, mining of those data becomes more important for effective processing of collected multi-spectral images. The most popular approaches for this problem use the meta-data of the images such as geographical coordinates etc. However, these approaches do not offer a good solution for determining what those images contain. Some researches make a big step from the meta-data based approaches in this area by moving the focus of the study to content based approaches such as utilizing the region information of the sensed images. In this thesis, we propose a novel, generic and extendable image information mining system that uses spatial relationship constraints. In this system, we use not only the region content, but also relationships of those regions. First, we extract the region information of the images and then extract pairwise relationship information of those regions such as left, right, above, below, near, far and distance etc. This feature extraction process is defined as a generic process which is independent from how the region segmentation is obtained. In addition to these, since new features and new approaches are continuously being developed by the image information mining researchers, extendability feature of the our system plays a big role while we are designing our system. In this thesis, we also propose a novel feature vector structure in which a feature vector consists of several sub-feature vectors. In the proposed feature vector structure, each sub-feature vector can be exclusively selected to be used for search process and they can have different distance metrics to be used in comparisons between the same sub-feature vector of the other feature vector structures. Therefore, the system gives ability to users to choose which information about the region and its pairwise relationship with other regions to be used when they perform a search on the system. The proposed system is illustrated by using region based retrieval scenarios on very high spatial resolution satellite images.Karakuş, FatihM.S

ODUN PLASTİK KOMPOZİTLERİN ÜRETİLMESİNDE TARIMSAL ATIKLARIN DEĞERLENDİRİLMESİ

Odun plastik kompozitler (OPK); odun unu ya da tarımsal atıkların polimer matrisi içerisine katılmasıyla üretilen kompozit malzemeler olarak adlandırılmaktadır. OPK üretiminde saf polimerler kullanılabildiği gibi geri dönüşüm (atık) polimerler de kullanılabilmektedir. Bu çalışmada orman endüstrisi veya lignoselülozik esaslı atıklar kullanılarak üretilen odun plastik kompozitlerin mekanik ve morfolojik özellikleri belirlenmiştir.  Bu amaçla okaliptus odun unu, pamuk karpeli ve buğday sapları kullanılmıştır.  Termoplastik malzeme olarak geri dönüşüm yüksek yoğunluklu polietilen (YYPE) değerlendirilmiştir. Kompozit örneklerin üretimi ekstrüzyon ve pres kalıplama yöntemi kullanılarak gerçekleştirilmiştir. Üretilen kompozit örnekler üzerinde çekme ve eğilme direnci, elastikiyet modülü ve darbe direnci değerleri ASTM standartları takip edilerek belirlenmiştir. Elektron mikroskobu yardımıyla morfolojik özellikleri belirlenmiştir.  Bu tip odun plastik kompozit malzemeler mobilya endüstrisinde kapı-pencere doğraması, park-bahçe mobilyası ve kamelya malzemesi gibi kullanılma potansiyelleri bulunmaktadır

INVESTIGATION OF DIFFERENCES LEVELS OF PERCEIVED FREEDOM IN LEISURE BETWEEN INDIVIDUALS WHICH ARE PARTICIPATED IN NATURE SPORTS AND MEMBERS OF FITNESS CENTERS

The purpose of this study is; to identify the difference between the level of freedom perceived by individuals participating in fitness centers and nature sports. A total of 202 participants, 84 of whom were members of Nature Sports clubs in İzmir, Manisa and Kütahya, participated in at least 1 nature sports event per month and 118 people who were members of fitness centers for at least 3 months. In the study, data collection tool, Perceived Freedom in Leisure, was developed by Witt and Ellis (1985) and adaptation to Turkish was done by Yerlisu Lapa and Agyar (2011). In the research, descriptive analysis, MANOVA and Two-Way Anova tests were used. As a result of the analysis; while the activities of the participants influenced the level of freedom they perceived in free time, no significant difference was observed in terms of age and difficulty in participating in the activity. Although freedom levels perceived in free time did not show a significant change in terms of both age and difficulty, changes were observed according to the activity performed

Synthesis and Biological Evaluation of Some Hydrazide-Hydrazone Derivatives as Anticancer Agents

In this study, a series of hydrazide-hydrazone derivatives (3a-3u) were synthesized and evaluated for their anticancer activities against prostate cancer cell line (PC-3), breast cancer cell line (MCF-7), colon cancer cell line (HT-29) and human umbilical vein endothelial cells (HUVEC) using MTT assay. In particular, compound 3h having a pyrrole ring was found to be the most potent derivative with IC50 = 1.32, 2.99, 1.71 µM against PC-3, MCF-7, HT-29 cancer cell lines respectively using paclitaxel as a standard compound. Furthermore, compound 3h was subjected to further biological studies such as caspase-3 activity and Annexin-V assay to evaluate their inhibitory potentials. The activity results displayed that compound 3h increased caspase-3 activation and the number of cells to early apoptosis. The additional studies like pharmacokinetics, bioavailability scores and drug-likeness properties were also evaluated. The in silico pharmacokinetics predictions displayed that the bioavailability of these compounds may be high

Conventional and Diffusion-Weighted MR Imaging Findings of Parotid Gland Tumors

Objective: To investigate diffusion-weighted magnetic resonance imaging (MRI) findings of parotid gland lesions in addition to conventional MRI findings and demographic data.Methods: A retrospective evaluation was made of the demographic data, histopathologic data, preoperative conventional and diffusion-weighted MRI of 74 patients who underwent parotidectomy. The patients were categorized according to the histopathology (pleomorphic adenoma [PA], Warthin’s Tumor [WT] and malignant Tumor [MT]).Results: Histologically, 30 patients had PA, 27 patients had WT, and the remaining 17 patients had MT. The mean age of the PA, WT and MT groups were 44±21 (20-72), 55±10 (41-71) and 62±20 (21-76) years, respectively. The WT (81%) and MT (70%) groups were male dominant, while the PA group showed female dominance (55%). The PA group showed statistically significant difference in terms of age (p<0.05) and gender (p=0.009) compared to the other two groups. The median apparent diffusion coefficient (ADC) values for the PA, WT and MT groups were 1.99±0.94 (1.10-2.41) x 10-3 mm2/s, 0.92±0.35 (0.21-1.79) x 10-3 mm2/s and 1.20±0.34 (0.78-1.47) x 10-3 mm2/s, respectively. PA was differentiated from the other two groups (p=0.001). The sensitivity and specificity for distinguishing PAs from WT was 97% and 85%, respectively, when the ADC cutoff value was 1.25; and for distinguishing PAs from MT was 77% and 83%, respectively, when the ADC cutoff value was 1.35.Conclusion: ADC measurements are useful for the differentiation of PA from both WT and MT; and can be used as a complementary tool to predict the histopathology in the preoperative planning of parotid tumors