Başkent University

About: Başkent University is a education organization based out in Ankara, Turkey. It is known for research contribution in the topics: Transplantation & Population. The organization has 4652 authors who have published 10380 publications receiving 143117 citations. The organization is also known as: Başkent Üniversitesi.

Design and Implementation of a 154-kV $\pm$ 50-Mvar Transmission STATCOM Based on 21-Level Cascaded Multilevel Converter

Abstract: In this research work, the design and implementation of a 154-kV ± 50-Mvar transmission static synchronous compensator (T-STATCOM) have been carried out primarily for the purposes of reactive power compensation and terminal voltage regulation and secondarily for power system stability. The implemented T-STATCOM consists of five 10.5-kV ±12-Mvar cascaded multilevel converter (CMC) modules operating in parallel. The power stage of each CMC is composed of five series-connected H-bridges (HBs) in each phase, thus resulting in 21-level line-to-line voltages. Due to modularity and flexibility of implemented HBs, each CMC module has reached a power density of 250 kvar/m3, thus making the mobility of the system implementable. DC-link capacitor voltages of HBs are perfectly balanced by means of the modified selective swapping algorithm proposed. The field tests carried out at full load in the 154-kV transformer substation where T-STATCOM is installed have shown that the steady-state and transient responses of the system are quite satisfactory.

Pre-Service Elementary School Teachers' Learning Styles and Attitudes towards Mathematics

Abstract: The purpose of this study was to investigate the differences of pre-service elementary school teachers’ attitudes towards mathematics according to their learning styles. Two hundreds eighty one pre-service elementary school teachers were involved in this study. The researchers employed two types of instruments, Learning Style Inventory and Scale of Mathematics Attitude Questionnaire, to collect the data. The learning style inventory was designed to detect the participants’ learning styles, Divergent, Assimilator, Convergent, and Accommodator, and the scale of mathematics attitude questionnaire was used to find the participants’ attitudes towards mathematics. After the collection of the data, the researchers run the one-way ANOVA to show the attitude differences based on the learning styles. The study concluded that there were statistically significant differences found between the attitudes of learners, convergent and assimilator, and that the convergent learners had more positive attitudes towards mathematics than the assimilator learners.

Fertility-Sparing Therapy in Young Women With Endometrial Cancer: 2010 Update

Abstract: Endometrial cancer (EC) in young and especially null gravid women is a challenging problem with increasing frequency due to both detailed investigations for infertile couples seeking treatment in in vitro fertilization centers and women delaying their plans for pregnancy. Considering very low number of such cases in the literature, fertility-sparing therapy for EC in young women is not standard, although it is widely used. In this review we searched the relevant literature, reviewed selection criteria, therapeutic options, response rates to therapy, special challenges, reproductive outcomes, and follow-up strategies for young women diagnosed with EC.