http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
An IEEE 802.15.4g SUN Compliant MR-OFDM RF CMOS Transceiver for Smart Grid and CEs
서영호,이승식,김창완 한국과학기술원 반도체설계교육센터 2015 IDEC Journal of Integrated Circuits and Systems Vol.1 No.1
This paper proposes an IEEE 802.15.4g SUN (Smart Utility Network) OFDM-based 920 MHz RF CMOS transceiver. It can be adopted in energy saving intelligent green homes, which are related to Smart Grid, as well as universal remote controller, building automation, which is related to CEs (Consumer Electronics), and other areas. With the proposed SUN OFDM-based RF transceiver, wireless connectivity among CE devices or among electric metering systems can considerably save electronic energy and make our lives more comfortable. The proposed RF transceiver consists of a RF front-end with an on-chip RF switch, a Tx BBA (Baseband Analog), a Rx BBA, and a PLL. The proposed RF transceiver is implemented in 0.18-μm CMOS technology and consumes 37 mA in Tx mode and 38 mA in Rx mode from a 1.8 V supply voltage. With the fabricated RF transceiver chip, two successful public demonstrations have been carried out, which show the possibility of its use in commercial products.
백년초 추출물 처리가 신선절단 사과의 갈변억제와 Staphylococcus aureus 증식에 미치는 영향
서영호 한국식품위생안전성학회 2012 한국식품위생안전성학회지 Vol.27 No.4
The dual effectiveness of Opuntia ficus indica extracts for browning inhibition and microbial inactivation on fresh-cut apples was investigated. Prepared apple slices were treated with 25, 50, 100, 200 mg/mL Opuntia ficus indica extracts, packaged in polyethylene bags, and stored for 10 days at 4, 21oC. Results indicate that Opuntia ficus indica extracts significantly (P < 0.05) inhibited the browning reaction of fresh-cut apples. This treatment also reduced peroxidase activities. The populations of Staphylococcus aureus significantly decreased with increasing extract concentration (p < 0.05). In particular, S. aureus was reduced to non-detectable levels after 2 days in 100 mg/mL treatment at 4oC and 21oC. Opuntia ficus indica extracts therefore have antibacterial and antibrowning effects. The results suggest that Opuntia ficus indica extracts could be useful as a natural food preservative.
Wire rod 소재의 인산염 피막 손상과 마찰계수의 정량적 분석 연구
서영호 한국기계기술학회 2021 한국기계기술학회지 Vol.23 No.6
A wire rod, a material for multistage cold forging, is subjected to spheroidization and low annealing heat treatment to secure formability, and a phosphate coating treatment on the material surface to secure lubricity. The film layer produced by the phosphate treatment process is involved in adhesion to the material surface, adhesion to the forging die surface, and lubricity. This results in the increase or decrease of the forming load and the increase or decrease of the die life in the cold forging process. In particular, as the cold forging process progresses, the phosphate film is damaged and the original performance is deteriorated, so there is a high possibility of process defects. In case of excessive damage, the film is completely lost and die soldering occurs. Therefore, in this study, quantitative criteria for phosphate film damage are presented and the effect on the cold forging process is analyzed based on this to improve process analysis prediction accuracy. Therefore, in this study, quantitative criteria for phosphate film damage are presented, and based on this, the friction coefficient in the multi-stage cold forging process is to be derived.
깊이 및 텍스쳐 영상 기반의 3D 입체 영상을 위한 워터마킹 알고리즘
서영호,김보라,김동욱,Seo, Young-Ho,Kim, Bo-Ra,Kim, Dong-Wook 한국정보통신학회 2014 한국정보통신학회논문지 Vol.18 No.3
3차원 영상을 생성하기 위해 깊이영상과 텍스쳐 영상의 활용이 보편화되면서 이들 영상에 대한 보호도 많은 관심을 받고 있다. 본 논문에서는 깊이와 텍스쳐 영상으로부터 임의의 시점에 생성되는 스테레오 및 다시점 영상의 소유권을 보호하기 위한 워터마킹 기법을 제안한다. 3D 워핑을 이용한 DIBR을 통해서 워터마크가 보존될 수 있도록 대상 영역을 설정한 이후에 2차원 DCT를 통해서 텍스쳐 영상을 주파수 계수로 변환한다. 이 계수의 일부를 양자화하여 워터마크를 삽입한다. 삽입된 워터마크는 확인이 되지 않기 때문에 비가시성을 확인할 수 있었고, 일반적인 영상처리 공격에 의해서 강인함을 확인하였다. Since the depth and texture images have been widely used for generating 3-dimensional stereoscopic image, the security of them have been focused. In this paper, we propose a new watermarking technique for copyright of stereo and multiview images which is generated in an arbitrary viewpoint by depth and texture image. After the mark space is selected for preserving watermark through DIBR (depth-image-based rendering) process which uses 3D warping, the texture image is transformed to the frequency coefficient using 2D DCT (discrete cosine transform). Some parts of them are quantized, which is the corresponding process to watermarking. The embedded watermark is not conformed by eyes, so we identified the invisibility of the proposed method. In case of appling attacks of general image process, we also identified the robustness of it.
COX-2 억제제에 의한 AKT 경로를 통한 구강편평세포암종 세포주의 세포사멸 유도
서영호,한세진,이재훈,Seo, Young-Ho,Han, Se-Jin,Lee, Jae-Hoon 대한악안면성형재건외과학회 2008 Maxillofacial Plastic Reconstructive Surgery Vol.30 No.1
The objectives of this study was to check up the effect of celecoxib, COX-2 inhibitor, on the pathogenesis of oral squamous cell carcinoma. After mefenamic acid, aspirin and celecoxib, COX-2 inhibitor, were inoculated to HN 22 cell line, the following results were obtained through tumor cell viability by wortmannin, growth curve of tumor cell line, apoptotic index, PGE2 synthesis, total RNA extraction, RT-PCR analysis and TEM features. 1. When wortmannin and celecoxib were given together, the survival rate of tumor cells was lowest about 47 %. So wortmannin had an effect on the decrease of survival rate of tumor cells. 2. In growth curve, the slowest growth was observed in celecoxib inoculated group. 3. The synthesis of PGE2 was decreased in all group and the obvious suppression and highest apoptotic index was observed in celecoxib inoculated group. 4. Suppression of expression of COX-2 mRNA was evident in celecoxib inoculated group. But that of COX-1,2 mRNA was observed in mefenamic acid inoculated group and aspirin inoculated group. 5. In celecoxib inoculated group, mRNA expression of AKT1 was decreased and that of PTEN & expression of caspase 3 and 9 was evidently increased. Depending on above results, when celecoxib was inoculated to oral squamous cell carcinoma cell line, an increase of mRNA expression of caspase 3,9 and PTEN is related to a decrease of mRNA expression of AKT1. Wortmannin had an effect on the decrease of survival rate of tumor cells. Celecoxib might induce apoptosis of tumor cell by suppression of AKT1 pathway and COX-2 inhibition. This results suggested that COX-2 inhibitor might be significantly effective in chemoprevention of oral squamous cell carcinoma.