• Journal of Biomedical Engineering Research
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• v.13 no.4
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• pp.323-330
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• 1992

A Study of Image Compression Algorithm using DCT This paper describes the system that implement a JPEG(Joint Photographic Experts Group) algorithm based on DCT(Discrete Cosine Transform) uslng CCD kameva, Image Grabber, and IBM PC. After cosine transforms the acquisited image, this algorithm quantize and entropy encode the coefficients by JPEG code table. The coefficients are reconstructed by the Huffman decoding, dequantized procedure, and Inverse cosine transform. The results obtained from the impleulented system are as follows. (1) For effcient storage and easy implementation, this system save Image as a PCX formal (2) Thls system get 7:1 compression ratio(3.8 RMSE value) without large distortion. (3) With a low pass filtering, thls system eliminate high frequency components and get 20% enhanced compression ratio. (4) Thls system enhance the reconstructed Image using histogram modeling.

• Journal of IKEEE
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• v.6 no.1 s.10
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• pp.10-20
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• 2002

The purpose of this work is to develop a system fer rapid and automatic identification of persons, with high reliability and confidence levels. The iris of the eye is used as an optical fingerprint, having a highly detailed pattern that is unique for each individual and stable over many years. Image analysis algorithms find the iris in a image, and encode its texture into an iris code. Iris texture is extracted from the image at multiple scales of analysis by wavelet transformation. The features of many different parts of the iris are projected onto the space-frequency space. They are used to determine an abstract iris code which is similar to 2D barcode. Pattern recognition is achieved by using modified CPN.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.1
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• pp.109-117
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• 2012

This paper addresses influence on the flow field by varying the length of DPF Inlet pipe in 5 ways. Numerical analysis is carried out by using PIV and commercial code and as a result, PIV and commercial code shows correlation correspond to 87%. Furthermore, in the same velocity condition, as stable and high pressure value is shown when the Inlet pipe length is 20mm, particulate filtering rate can be increased.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.10
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• pp.63-71
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• 1996

This paper proposes a method which analyzes facial shape and extracts positions of eyes regardless of the tilt and the size of input iamge. With the extracted feature parameters of facial element by the method, full human faces are recognized by a neural network which BP algorithm is applied on. Input image is changed into binary codes, and then labelled. Area, circumference, and circular degree of the labelled binary image are obtained by using chain code and defined as feature parameters of face image. We first extract two eyes from the similarity and distance of feature parameter of each facial element, and then input face image is corrected by standardizing on two extracted eyes. After a mask is genrated line historgram is applied to finding the feature points of facial elements. Distances and angles between the feature points are used as parameters to recognize full face. To show the validity learning algorithm. We confirmed that the proposed algorithm shows 100% recognition rate on both learned and non-learned data for 20 persons.

• Journal of Internet of Things and Convergence
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• v.2 no.4
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• pp.15-20
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• 2016

This paper describes the construction of knowledge data retrieval management system based on medical image CT. The developed system is aimed to improve the efficiency of the hospital by reading the medical images using the intelligent retrieval technology and diagnosing the patient 's disease name. In this study, the medical image DICOM file of PACS is read, the image is processed, and feature values are extracted and stored in the database. We have implemented a system that retrieves similarity by comparing new CT images required for medical treatment with the feature values of other CTs stored in the database. After converting 100 CT dicom provided for academic research into JPEG files, Code Book Library was constructed using SIFT, CS-LBP and K-Mean Clustering algorithms. Through the database optimization, the similarity of the new CT image to the existing data is searched and the result is confirmed, so that it can be utilized for the diagnosis and diagnosis of the patient.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1603-1606
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• 2005

Eye Glass Display (EGD) with microdisplay to realize the virtual display can make the large screen, so virtual image has been developed by using microdisplay panel. This paper shows study of low cost lens design and simulation for microdisplay system with 0.6" Liquid Crystal on Silicon (LCoS) panel. Lens design optimized consider to spherical aberration, astigmatism, distortion, and chromatic aberration. Code V is used and it designed an aspheric lens about exit pupil 6mm, eye relief 20mm and 35 degree of field of view (FOV). With the application this aspheric lens to LCOS type's microdisplay, virtual image showed 50 inch at 2m. One side of the aspheric lens was constituted from diffractive optical element (DOE) for the improvement in a performance. It had less than ${\pm}2%$ of distortion value and modulation transfer function in axial had 20% of resolution with 30 lp/mm spatial frequency. The optical system is suitable for display of 0.6"-diagonal with SVGA.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.6
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• pp.825-830
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• 2010

Generally, the copy protection mark and 2D bar-code techniques are widely used for forgery protection in printed public documents. But, it is hard to discriminate truth from the copy documents by using exisiting methods, because of that existing 2D-barcode is separated from the copy protection mark and it can be only recognized by specified optical barcord scanner. Therefor, in this paper, we proposed the forgery protection tehchnique for discriminating truth from the copy document by using watermark inserted 2D-barcord, which can be accurately distinguished not only by naked eye, but also by scanner. The copy protection mark consists of deformed patterns that are caused by the lowpass filter characteristic of digital I/O device. From these, we verified the performance of the proposed techniques by applying the histogram analysis based on the original, copy, and scanned copy image of the printed documents. Also, we suggested 2D-barcord confirmation system which can be accessed through the online server by using certification key data which is detected by web-camera, cell phone camera.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.13-20
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• 2014

In this paper, we implemented the object scanning with nxtOSEK which is an open source platform. nxtOSEK consists of device driver of leJOS NXJ C/Assembly source code, TOPPERS/ATK(Automotive real time Kernel) and TOPPERS/JSP Real-Time Operating System source code that includes ARM7 specific porting part, and glue code make them work together. nxtOSEK can provide ANSI C by using GCC tool chain and C API and apply for real-time multi tasking features. We experimented the 3D scanning with ultra sonic and laser sensor which are made directly by laser module diode and experimented the measurement of scanning the object by knowing x, y, and z coordinates for every points that it scans. In this paper, the laser module is the dimension of $6{\times}10[mm]$ requiring 5volts/5[mW], and used the laser light of wavelength in the 650[nm] range. For detecting the object, we used the beacon detection algorithm and as the laser light swept the objects, the photodiode monitored the ambient light at interval of 10[ms] which is called a real time. We communicated the 3D scanning platform via bluetooth protocol with host platform and the results are displayed via DPlot graphic tool. And therefore we enhanced the functionality of the 3D scanner for identifying the image scanning with laser sensor modules compared to ultra sonic sensor.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.8
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• pp.1309-1321
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• 2008

Military style is not limited to a single period but represents various image communications related to items, synthetic images and different periodical culture backgrounds. The purpose of this study is to define the communicational function of the military style beginning from the 1st world war up to the modern days, and furthermore explain the characteristics and contents of military styles in different periods by studying the nowadays various symbols of the military style in denotative and connotative aspects. The research method is documentary studies through the literature and academic paper, and examined masters' and doctors' thesis, domestic and overseas books and fashion magazines, photographs and materials collected from the internet. As a result, first, the military style is a significant fashion code in understanding modern fashion by serving as a strong communication function representing people’s ritual through various image items called the 'military look'. Second, the meaning of the image communication through military look changed throughout the different periods. During the 1st and 2nd World war the military look supported Fascism by serving as a media representing extreme patriotism and at the same time social images like functionalism, women liberation, regulation and saving. During the cold war period it was used by young progressives like hippies and punks to send an opposing message towards war and commercialism. Since then up to the 80s it was a medium representing the ‘new role of women’, who possess same social rights and power as the men. However in the 90s the military style had to go through a paradigm transition period. Since this period it got affected by the post modernism and designers, consumers alike adopted military style to create unique beauty It can also be said that it began to be used as a pure fashion code representing intertextuality. It was rather expressed as a metonymy than a metaphor and combined with elegance and feminine factor, which contrasts to the original military concept, it now represents totally new hybrids such as difference, dissemination and varieties.

• Journal of the Optical Society of Korea
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• v.20 no.4
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• pp.476-480
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• 2016

For the application of multiusers, the arrangement and distribution of the keys is a much concerning problem in a cryptosystem. In this paper, we propose an optical encryption scheme with multiple users based on computational ghost imaging (CGI) and orthogonal modulation. The CGI encrypts the secret image into an intensity vector rather than a complex-valued matrix. This will bring convenience for post-processing and transmission of the ciphertext. The orthogonal vectors are taken as the address codes to distinguish users and avoid cross-talk. Only the decryption key and the address code owned by an authorized user are matched, the secret image belonging to him/her could be extracted from the ciphertext. Therefore, there are two security levels in the encryption scheme. The feasibility and property are verified by numerical simulations.