Abstract-Channel polarization is a method of constructing capacity achieving codes for symmetric binary-input discrete memoryless channels (B-DMCs) [1]. In the original paper, the construction complexity is exponential in the blocklength. In this paper, a new construction method for arbitrary symmetric binary memoryless channel (B-MC) with linear complexity in the blocklength is proposed. Furthermore, new upper bound and lower bound of the block error probability of polar codes are derived for the BEC and arbitrary symmetric B-MC, respectively.

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Hyalinization of choroidal vessels, like arteriosclerosis, is characteristic of PCV.

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Polarization phenomenon over any finite field Fq with size q being a power of a prime is considered. This problem is a generalization of the original proposal of channel polarization by Arıkan for the binary field, as well as its extension to a prime field by Ş aşoglu, Telatar, and Arıkan. In this paper, a necessary and sufficient condition of a matrix over a finite field Fq is shown under which any source and channel are polarized. Furthermore, the result of the speed of polarization for the binary alphabet obtained by Arıkan and Telatar is generalized to arbitrary finite field. It is also shown that the asymptotic error probability of polar codes is improved by using the Reed-Solomon matrices, which can be regarded as a natural generalization of the 2 × 2 binary matrix used in the original proposal by Arıkan.

A method of channel polarization, proposed by Arıkan, allows us to construct efficient capacity-achieving channel codes. In the original work, binary input discrete memoryless channels are considered. A special case of q-ary channel polarization is considered by Ş aşoglu, Telatar, and Arıkan. In this paper, we consider more general channel polarization on q-ary channels. We further show explicit constructions using ReedSolomon codes, on which asymptotically fast channel polarization is induced.

Both initial and deferred PDT combined with IVR to treat polypoidal choroidal vasculopathy show the similar visual and anatomical improvements at 12 months. Initial PDT combination leads to significantly fewer additional treatments.

. Purpose:  We assessed the characteristic indocyanine green angiographic (ICGA) and spectral domain optical coherence tomographic (SD‐OCT) findings of two types of polypoidal choroidal vasculopathy (PCV), distinguishable by different filling patterns on ICGA. Methods:  Thirty‐one eyes with PCV were classified into types 1 and 2 based on ICGA findings of either the presence or absence of both a feeder and a draining vessel. Characteristic ICGA findings were evaluated for each type of PCV. Spectral domain optical coherence tomographic images of the 31 eyes were also used to compare the two types of PCV. Results:  Both a feeder and a draining vessel were observed in 13 eyes (type 1). Eighteen eyes had neither feeder nor draining vessels (type 2). In PCV type 1, a break in the highly reflective line thought to be Bruch’s membrane was detected, corresponding to the feeder vessel in‐growth site on SD‐OCT. This line was straight. In PCV type 2, the highly reflective line exhibited irregular thickness and had highly reflective substances adhering to its lower portion. It curved downward and became increasingly obscure, ultimately disappearing at a point corresponding to the site at which network vessel filling began. The mean subfoveal choroidal thicknesses in eyes with PCV type 1 and PCV type 2 were 199 ± 65 and 288 ± 98 μm, respectively. Conclusions:  Our observations support the existence of two distinct types of PCV. The first type represents choroidal neovascularization, whilst the second type involves choroidal vasculature abnormalities.