We study electromagnetic plane wave diffraction by a hollow circular cone with thin walls modelled by the so-called impedance-sheet boundary conditions. By means of Kontorovich–Lebedev integral representations for the Debye potentials and a ‘partial’ separation of variables, the problem is reduced to coupled functional difference (FD) equations for the relevant spectral functions. For a circula...

This article first reviews recently proposed techniques for adaptive and direct linear MIMO equalization in the context of MIMO-CDMA systems and in particular with application to a MIMO-extended UMTS-FDD downlink. The focus is thereby mainly on the complexity of the algorithms. The second part of the paper proposes frequency domain (FD) MIMO equalization using the overlap/add FFT method in conj...

This study explored the imaging capability of our frequency-domain photoacoustic (FD-PA) system that utilizes correlation processing alias “photoacoustic radar” and ultrasonic phased array for imaging of soft tissues. The probe imaging capabilities were studied using tissuemimicking phantoms, tissue samples ex vivo, blood vessels in a human wrist and a rat tumour model in vivo. Our experimental...

AKL(FD) is an integration of (an extension of) the nite domain constraint system FD in AKL, a deep concurrent constraint programming language CJH94]. In this paper we describe the implementation of the FD solver and its adaptation to the generic constraint interface of the AGENTS implementation of AKL. We also describe compilation techniques used by the AKL(FD) compiler. 1 Introduction Conceptu...

Fourier domain mode locked (FDML) lasers are excellent tunable laser sources for frequency domain optical coherence tomography (FD-OCT) systems due to their combination of high sweep rates, large tuning ranges, and high output powers. However, conventional FDML lasers provide coherence lengths of only 4-10 mm, limiting their use in demanding applications such as intravascular OCT where coherenc...

We have proposed a new frequency difference method using a weighted voltage difference (WFD-EIT) between two frequencies [1, 2]. Previous studies demonstrated its feasibility through numerical experiments and two-dimensional phantom experiments. In this study, we validate the WFD-EIT algorithm on a three-dimensional hemisphere phantom using a multi-frequency EIT system KHU Mark1. We built the h...

Near-infrared spectroscopy (NIRS) is increasingly used in neonatal intensive care. We investigated the impact of skin, bone, and cerebrospinal fluid (CSF) layer thickness in term and preterm infants on absorption-(μa) and/or reduced scattering coefficients (μs') measured by multidistance frequency-domain (FD)-NIRS. Transcranial ultrasound was performed to measure the layer thicknesses. Correlat...

Smoke inhalation injury is frequently accompanied by cyanide poisoning that may result in substantial morbidity and mortality, and methods are needed to quantitatively determine extent of airway injury. We utilized a 3-D endoscopic frequency-domain optical coherence tomography (FD-OCT) constructed with a swept-source laser to investigate morphological airway changes following smoke and cyanide ...

AIMS We investigated the feasibility of thrombus quantification by frequency-domain optical coherence tomography (FD-OCT) methods in patients with highly thrombotic acute coronary syndrome (ACS) treated by deferred stenting strategy. METHODS AND RESULTS Patients were suitable for inclusion if they presented (i) an ACS that was successfully revascularized by manual thrombo-aspiration and (ii) ...

In this paper, a new block adaptive filtering algorithm, based on the conjugate gradient (CG) method of optimization, is proposed. A Toeplitz approximation of the auto-correlation matrix is used for the estimation of the gradient vector and the involved quantities are updated on a block by block basis. Due to this formulation, the algorithm can be efficiently implemented in the frequency domain...