이정우 교수

The immunomodulatory and antitumor effects of lactic acid bacteria (LABs) were investigated. Cytoplasmic fraction of Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium longum were tested for the antiproliferative activity in vitro to SNUC2A, SNU1, NIH/3T3 and Jurkat cell lines by crystal violet assay. All cytoplasmic fraction suppressed proliferation of tumor cells, though L. casei and B. longum were more effective. From these results, cytoplasmic fraction of L. casei and B. long

In this paper we present a novel technique to dynamically adapt motion interpolation structures by temporal segmentation. The number of reference frames and the intervals between them are adjusted according to the temporal variation of the input video. Bit-rate control for this dynamic group of pictures (GOP) structure is achieved by taking advantage of temporal masking in human vision. Constant picture quality can be obtained by variable-bit-rate coding using this approach. Further improvement

We present an algorithm for joint optimization of anchor frame separation and bit allocation for motion-compensated video coders. The anchor frame separation is optimized in the sense that the distortion is minimized under a bit budget constraint. At the same time, the quantization for each frame in a group of pictures is also optimized in an operational rate distortion sense. The optimal anchor frame separation does depend on the quantization of each frame so that the two optimization problems

We propose a novel collaborative filtering algorithm based on deep neural networks. We use normalized user-rating vector and normalized item-rating vector as inputs to a neural network. The batch normalization technique is used for each layer to prevent neural networks from overfitting. Experimental results show that the proposed method outperforms conventional collaborative filtering algorithms. Based on the results, its performance is comparable to the well-known Netflix prize winning algorith

In this paper, we present a new approach to find the best quadtree for variable block size (VBS) motion estimation for video coding. In this approach, the quantizer which encodes the prediction residual is also jointly optimized in a rate-distortion sense. The desired balance of the bit allocation between the motion vector coding and the residual error coding is achieved by a Lagrange multiplier approach for the joint optimization problem. A fast tree optimization technique is used to reduce the

A new multispectral image compression technique based on the Karhunen-Loeve transform (KLT) and the discrete cosine transform (DCT) is proposed. The quadtree for determining the transform block size and the quantizer for encoding the transform coefficients are jointly optimized in a rate-distortion sense. The problem is solved by a Lagrange multiplier approach. After a quadtree is determined by this approach, a one-dimensional (1-D) KLT is applied to the spectral axis for each block before the D

In this paper we present a multiresolution approach for video indexing and feature matching of subband coded video databases. Subband coding refers to a coding technique where the input images are quantized after being decomposed into several narrow spatial frequency bands by filtering and decimation. Five different approaches were tested for scene change detection which is applied only on the lowest subband for computational efficiency. Two kinds of scene changes, abrupt and smoothly accumulate

We present the Whirlpool Routing Protocol (WARP), which efficiently routes data to a node moving within a static mesh. The key insight in WARP's design is that data traffic can use an existing routing gradient to efficiently probe the topology, repair the routing gradient, and communicate these repairs to nearby nodes.

We consider information-theoretic privacy in federated submodel learning, where a global server has multiple submodels. Compared to the privacy considered in the conventional federated submodel learning where secure aggregation is adopted for ensuring privacy, information-theoretic privacy provides the stronger protection on submodel selection by the local machine. We propose an achievable scheme that partially adopts the conventional private information retrieval (PIR) scheme that achieves the

In this paper, we present an algorithm for joint optimisation of motion compensation structure and bit allocation for motion compensated video coders. In this scheme, the motion compensation structure is optimized in the sense that the distortion is minimized under a bit budget constraint. At the same time, the quantisation for each frame in the group of pictures (GOP) is also optimized in an operational rate distortion sense.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="htt

The I/Q unbalance which is generated by a non-ideal component is an inevitable physical phenomenon and leads to performance degradation when we implement a practical two-dimensional (2-D) modulation system. In this paper, we provide an. exact and general expression involving the 2-D Gaussian Q-function for the SER/BER of arbitrary 2-D signaling with I/Q amplitude and phase unbalances over an additive white Gaussian noise (AWGN) channel by using the coordinate rotation and shifting technique. Thr

Objectives: This study was conducted in order to assess the efficacy of 1st generation cephalosporin as use as a single-dose preoperative prophylactic antibiotic for surgical wound infections resulting from intra-oral bone grafting procedures. Materials and Methods: A total of 23 patients who were to undergo intra-oral bone graft procedures participated in this study. After randomization, 2 grams of 1st generation cephalosporin was orally administered to both the experimental and placebo groups

The field emission (FE) characteristics of indium oxide (In2O3)-coated single-walled carbon nanotubes (SWCNTs) were studied. Scanning electron microscopy, x-ray diffractometer, and UV/visible spectroscopy confirmed that In2O3 exists as a polycrystalline cubic bixbyite structure on the surface of SWCNTs. The turn-on field of pristine SWCNTs decreased from 3.82to3.27V∕μm for In2O3-coated SWCNTs with optimal coating thickness. The maximum emission current density reached 3.5mA∕cm2, five times highe