Yazar "Şişman, Alper" için listeleme
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An analog integrated circuit beamformer for high-frequency medical ultrasound imaging
Gürün, Gökçe; Zahorian, Jaime S.; Şişman, Alper; Karaman, Mustafa; Hasler, Paul E.; Değertekin, Fahrettin Levent (IEEE-INST Electrical Electronics Engineers Inc, 2012-10)We designed and fabricated a dynamic receive beamformer integrated circuit (IC) in 0.35-mu m CMOS technology. This beamformer IC is suitable for integration with an annular array transducer for high-frequency (30-50 MHz) ... -
Annular CMUT arrays for side looking intravascular ultrasound imaging
Zahorian, Jaime; Güldiken, Rasim Oytun; Gürün, Gökçe; Qureshi, Muhammad Shakeel; Balantekin, Müjdat; Değertekin, Fahrettin Levent; Carlier, Stephane; Şişman, Alper; Karaman, Mustafa (IEEE, 2007)Although side looking intravascular ultrasound (SL-IVUS) imaging systems using single element piezoelectric transducers set the resolution standard in the assessment of the extent of coronary artery disease, improvements ... -
Damariçi yanal kesit görüntüleme için farklı prob yapılarının incelenmesi
Şişman, Alper; Karaman, Mustafa (IEEE, 2009-06-26)Bu çalışmada dönen bir şaftın yanal yüzeyine yerleştirilmiş 8 adet içiçe halka elemanlardan oluşan yana bakan görüntüleme için yeni bir kateter yapısı incelenmiştir. Bu Katater mimarisi basit bir dizi önü alıcı verici ... -
Design and implementation of a low cost telematic control system
Şişman, Alper (Işık Üniversitesi, 2002-09)The thesis explains phases from ideation to concretize of a device that aims to solve continuously increase security needs in everyday life more effective, more reliable and cheaper way; however the device has so many ... -
Dual-annular-ring CMUT array for forward-looking IVUS imaging
Güldiken, Rasim Oytun; Zahorian, Jaime; Balantekin, Müjdat; Değertekin, Fahrettin Levent; Tekeş, Coşkun; Şişman, Alper; Karaman, Mustafa (IEEE, 2006)We investigate a dual-annular-ring CMUT array configuration for forward-looking intravascular ultrasound (FL-IVUS) imaging. The array consists of separate, concentric transmit and receive ring arrays built on the same ... -
Evaluation of CMUT annular arrays for side-looking IVUS
Şişman, Alper; Zahorian, Jaime S.; Gürün, Gökçe; Karaman, Mustafa; Balantekin, Müjdat; Değertekin, Fahrettin Levent; Hasler, Paul E. (IEEE, 2009)Side-looking (SL) IVUS probes are extensively used for management of cardiovascular diseases. Currently SL-IVUS imaging probes use either a single rotating transducer element or solid-state arrays. Probes with single ... -
Solid-state arrays and beamformers for side-looking intravascular ultrasonic imaging
Şişman, Alper (Işık Üniversitesi, 2010-06-08)Current solid-state intravascular ultrasound (IVUS) devices use a one-dimensional (1-D) rectangular array wrapped around the cylindrical catheter. Beamforming in these devices is limited to synthetic phased array processing, ... -
Solid-state SL-IVUS arrays based on non-uniform aperture sampling
Şişman, Alper; Karaman, Mustafa; Gürün, Gökçe; Değertekin, Fahrettin Levent (IEEE, 2010)We propose new reconfigurable ring and cylindrical array designs using non-uniform (Fresnel) aperture sampling with identical differential delays between adjacent elements which reduces the beamformer complexity. For ... -
A tunable analog delay element for high-frequency dynamic beamforming
Gürün, Gökçe; Şişman, Alper; Zahorian, Jaime S.; Satır, Sarp; Karaman, Mustafa; Hasler, Paul E.; Değertekin, Fahrettin Levent (IEEE, 2009)Implementing beamforming for high frequency arrays is challenging because of the accurate delay requirements at high frequencies. High frequency digital beamforming is not suitable for catheter based applications as a large ... -
Tıbbi ultrasonik kanal içi görüntüleme için yeni yöntemler
Karaman, Mustafa; Şişman, Alper; Tekeş, Coşkun (Tübitak, 2008-09)Yakın zamanda yapılan çalışmalarımızdaki yaklaşımda, aktif kanal sayısını azaltmak için fazlalık (redundant) gönderme-alma eleman ikilileri azalırken gerekli olan (non-redundant) gönderme-alma eleman ikilileri korunmaktadır. ...