• 한국세라믹학회지
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• 제37권5호
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• pp.438-443
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• 2000

This dissertation is focused on the study over the improvement for the early strength of belite-rich cement(BRC). For this purpose, the initial hydration behaviors according to addition of different calcium sulfate types were evaluated. From the observations by XRD, DSC and SEM, the BRC II and III with the addition of natural anhydrate and flue gas desulphurization(FGD) gypsum, respectively, formed much ettringite after 7 days more than the BRC I with the addition of chemical gypsum. The compressive strength of the BRC II and III developed outstandingly due to the formation of calcium aluminate hydrate within pores of hardened BRC paste. Especially, in the case of BRC III adding FGD with low impurities, the early as well as long term compressive strengths were shown very high, compared with other specimens.

• Archives of Reconstructive Microsurgery
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• 제20권2호
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• pp.121-125
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• 2011

Simple ganglions are most common benign tumor of the hand and wrist. However, cystic adventitial disease is an uncommon vascular anomaly first described in 1947 in the external iliac artery. It usually involves the popliteal artery, although other arteries and veins may also be involved. Radial artery adventitial cysts are found directly within the adventitia, whereas the more common wrist ganglions may extrinsically compress or adhere to the artery walls. The diagnosis is rarely made before surgery because of their similar appearance and location. The authors report a rare case of a 46-year old woman with mucoid adventitial cyst of the radial artery in the wrist.

• 대한임베디드공학회논문지
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• 제8권1호
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• pp.43-50
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• 2013

The narrow dynamic range of most smart phone cameras is severely limited. It usually is narrower than the dynamic range of most scenes. So we proposes a illuminance dynamic range expansion using multi-point knee for smart phone camera. Such as logarithmic functions the proposed method compress the image sensor output signal. Additionally, the proposed method was merged into the gamma that is essential circuit for any cameras. To justifying multi-point knee effectiveness, we configure the control and quality evaluation system for smart phone camera module. Experimental results show that the lost information by cut off and saturated affectively reconstructed in darker and in brighter areas. Finally this methods have advantage to implement without any changing hardware for conventional smart phones.

• ETRI Journal
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• 제32권6호
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• pp.972-975
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• 2010

In this letter, we consider the lossy coding of a non-uniform binary source based on GF(q)-quantized low-density generator matrix (LDGM) codes with check degree $d_c$=2. By quantizing the GF(q) LDGM codeword, a non-uniform binary codeword can be obtained, which is suitable for direct quantization of the non-uniform binary source. Encoding is performed by reinforced belief propagation, a variant of belief propagation. Simulation results show that the performance of our method is quite close to the theoretic rate-distortion bounds. For example, when the GF(16)-LDGM code with a rate of 0.4 and block-length of 1,500 is used to compress the non-uniform binary source with probability of 1 being 0.23, the distortion is 0.091, which is very close to the optimal theoretical value of 0.074.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.853-856
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• 2004

Image data processing on the region of interest (ROI) for providing the primary information is needed the view of saving search time and bandwidth over image communications related to web browsing, image database, and telemedicine, etc. Hence, the issue on extracting the region of interest is drawing a plenty of attention for the communication environment with a relatively low bandwidth such as mobile internet. In this paper, we propose a improved standard Maxshift method. The proposed algorithm compress image that includes multiple ROI using Maxshift method in Part 1 of JPEG2000. Simulation results show that proposed method increases PSNR vs. compression ratio performance above the Maxshift method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.53-54
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• 2015

As the result of uniaxial compression strength test on the CLMS mixing BFS and SS with BFS 4000, it required to determine the desired strength through increasing unit quantity of cement in mixing process because of dramatic strength deterioration of strength according to increasing replacing rate. In this study's result, regardless of differences in fine aggregates used, in order to get uniaxial compression strength in the scope exceeding criteria of minimum strength for applying to the field, the most reasonable combination was to mix replacing BFS with fineness of 6000 in 30%. For the CLMS mixing BFS and SS, in order to improve flow ability by securing quantity of minimum unit and to repress bleeding rate with securing uniaxial compress strength considering the field applicability, regardless of differences in fine aggregates used, to mix BFS over 6000 in 30% was most effective.

• 한국컴퓨터정보학회논문지
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• 제4권1호
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• pp.1-6
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• 1999

본 연구는 정지 영상을 무손실 압축하기 위해 영상 각 화소의 값 상위 4비트의 중복성을 이용하여 런랭스 코딩 전처리로 1차 압축을 수행한 후 허프만 코딩으로 무손실 압축률을 향상시키는 새로운 방법을 제시한다. 본 연구에서 제안된 방법은 영상의 종류에 따라 자동적으로 허프만 코딩과 전처리 허프만 코딩을 선택하도록 하고, 전처리는 상위 4비트와 하위 4비트를 분리하여 상위 4비트의 중복성을 이용하여 런 랭스 코딩을 하여 기존의 일반적인 허프만 방법보다 더 나은 결과를 나타내었다.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.455-460
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• 2002

As the transmission of 3D shape models through Internet becomes more important, the compression issue of shape models gets more critical. The issues for normal vectors have not yet been explored as much as it deserves, even though the size of the data for normal vectors can be significantly larger than its counterparts of topology and geometry. Presented in this paper is an approach to compress the normal vectors of a shape model represented in a mesh using the concept of clustering. It turns out that the proposed approach has a significant compression ratio without a serious sacrifice of the visual quality of the model.

• 전자공학회논문지 IE
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• 제47권2호
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• pp.27-31
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• 2010

본 논문에서는 무손실 압축을 위하여 예측기를 스위칭하는 알고리즘을 제안한다. 제안하는 방법은 MED(median edge detector), GAP(gradient adaptive prediction) 예측기의 예측 에러들에 따라 적응적으로 하나의 예측기를 이용하여 화소값을 예측한다. 그리고, 에러는 기존의 엔트로피 방법을 이용하여 측정한다. 실험 결과, 제안하는 알고리즘이 기존 예측 방법보다 적은 에러값과 엔트로피를 가짐으로써 향상된 압축을 할 수 있음을 보인다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.358-360
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• 2004

The digital images contain a significant amount of redundancy and require a large amount of data for their storage and transmission. Therefore, the image compression is necessary to treat digital images efficiently. The goal of image compression is to reduce the number of bits required for their representation. The image compression can reduce the size of image data using contractive mapping of original image. Among the compression methods, the mapping is affine transformation to find the block(called range block) which is the most similar to the original image. In this paper, we applied the neural network(SOM) in encoding. In order to improve the performance of image compression, we intend to reduce the similarities and unnecesaries comparing with the originals in the codebook. In standard image coding, the affine transform is performed with eight isometries that used to approximate domain blocks to range blocks.