• 대한전자공학회논문지SP
• /
• 제40권5호
• /
• pp.332-346
• /
• 2003

본 논문에서는 2차원 DWT(Discrete Wavelet Transform)를 이용하여 디지털 영상을 압축 및 복원할 수 있는 시스템을 구현하였다. 제시한 DWT 기반 영상압축 시스템은 크게 영상을 압축하는 FPGA 보드와 영상을 복원하는 응용 소프트웨어로 구성된다. 먼저 영상을 압축하는 FPGA는 A/D 변환기로부터 영상을 받아들여서 웨이블릿 변환을 이용하여 영상을 압축하고 PCI 인터페이스를 이용하여 PC로 저장하며, PC에 저장된 압축된 영상정보는 응용 소프트웨어를 이용하여 복원된다. 영상압축 시스템은 A/D 변환기에 동기하여 NTSC YCbCr(4:2:2)의 640×240 영상을 초당 약 60 필드 압축한다. 구현된 하드웨어는 APEX20KC EP20K1000CB652-7의 FPGA에서 11,120개의 LAB(Logic Array Block)와 27,456개의 ESB(Embedded System Block)를 사용하여 하나의 FPGA내에 사상되었다. 전체적으로 33MHz의 클럭을 사용하고 메모리 제어부는 100MHz의 클럭을 사용하여 동작한다.

• 한국재료학회지
• /
• 제20권10호
• /
• pp.543-549
• /
• 2010

The hydrogen energy had recognized clean and high efficiency energy source. The research field of hydrogen energy was production, storage, application and transport. The commercial storage method was using high pressure tanks but it was not safety. However metal hydride was very safety due to high chemical stability. Mg and Mg alloys are attractive as hydrogen storage materials because of their lightweight and high absorption capacity (about 7.6 wt%). Their range of applications could be further extended if their hydrogenation properties and degradation behavior could be improved. The main emphasis of this study was to find an economical manufacturing method for Mg-Ti-Ni-H systems, and to investigate their hydrogenation properties. In order to examine their hydrogenation behavior, a Sievert's type automatic pressure-compositionisotherm (PCI) apparatus was used and experiments were performed at 423, 473, 523, 573, 623 and 673 K. The results of the thermogravimetric analysis (TGA) revealed that the absorbed hydrogen contents were around 2.5wt.% for (Mg8Ti2)-10 wt.%Ni. With an increasing Ni content, the absorbed hydrogen content decreased to 1.7 wt%, whereas the dehydriding starting temperatures were lowered by some 70-100 K. The results of PCI on (Mg8Ti2)-20 wt.%Ni showed that its hydrogen capacity was around 5.5 wt% and its reversible capacity and plateau pressure were also excellent at 623 K and 673 K.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 1999년도 추계종합학술대회
• /
• pp.199-203
• /
• 1999

본 논문은 MPEG-2 AAC 멀티채널 오디오 및 MPEG-4 오디오의 다중객체 부호화를 위한 DSP 시스템의 설계 및 구현에 관하여 기술한다. DSP로서는 TI 사의 최근 제품인 고성능의 TMS320C6701 (이하 6701로 함) 2개를 사용하였고, DSP 보드는 PC에 장착하여 프로그램을 다운로드하고 시스템을 제어할 수 있게 하기 위하여 PCI 인터페이스를 함께 구현하였으며, 부호화기 및 복화기로서 함께 사용할 수 있는 구조로서 설계하였다. 또한 멀티채널 오디오를 디지털 신호로 변환하고 다중화하여 직렬신호로서 입력하고, 다시 역으로 출력하기 위한 시스템을 별도로 외부에 구현하였으며, 접속 인터페이스로서 ADI (Alesys Digital audio Interface)론 사용하여, ADI 인터페이스를 지원하는 멀티채널오디오 장비론 입출력 시스템으로 사용할 수 있도록 하였다. 현재의 결과로서는 MPEG-2 AAC 4채널 오디오를 2개의 DSP를 사용하여 실시간으로 안정되게 부호화 할 수 있으며, 1개의 DSP로도 8채널까지의 복호화가 가능함을 확인하였다.

• 인터넷정보학회논문지
• /
• 제15권2호
• /
• pp.41-47
• /
• 2014

본 논문은 도시기상모델인 전산유체역학모델(CFD_NIMR)을 GP-GPU에서 실행시키기 위해 CUDA Fortran 병렬프로그램을 구현하였다. GP-GPU는 원래 PCI 카드 형태의 그래픽 처리 장치이지만 저비용, 저전력으로 대량의 계산을 초고속으로 수행할 수 있는 일반 계산 가속기이다. 모델을 단일 Intel XEON 2.0 GHz CPU에서 실행한 결과와 Nvidia Tesla C1060 GPU에서 실행한 성능을 비교하였을 때 GP-GPU에서 15배 정도의 빠른 속도를 보였다. 또한 다중 CPU를 사용한 MPI 병렬프로그램과 비교한 경우에도 GP-GPU에서 보다 더 효율적인 성능을 보였다. 본 논문에서 제시한 프로그램 방식은 유사한 구조를 가진 수치모델을 GP-GPU 병렬 프로그램으로 구현하는데 쉽게 적용할 수 있을 것으로 기대한다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
• /
• pp.469-471
• /
• 2002

This paper presents analysis of the IEEE802.11 MAC protocol and implementation of the asynchronous communication portion of the IEEE802.11 MAC protocol. we have used PRISM2 chipsets from intertsil to build physical layer and PCI controller from PLX to interface LLC layer. This study is shown to be able to apply to MAC implementation in high speed LAN.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.216-218
• /
• 2003

QuickBird satellite is quickly becoming the best choice for high-resolution mapping using satellite images. In this paper, we will describe the followings: (1) how to correct QuickBird data using different geometric correction methods, (2) data fusion using QuickBird panchromatic and multispectral data, and (3) automatic DEM extraction using QuickBird stereo data.

• 임상간호연구
• /
• 제23권1호
• /
• pp.83-90
• /
• 2017

Purpose: This study was to develop evidence-based clinical practice guideline in order to prevent contrastinduced nephropathy (CIN) for patients undergoing percutaneous coronary intervention (PCI). Methods: The guideline was developed based on the "Scottish Intercollegiate Guidelines Network (SIGN)". The first draft of guideline was developed through 5 stages and evaluated by 10 experts.(1) Clinical questions were ensured in PICO format.(2) Two researchers conducted a systematic search through electronic database, identifying 170 studies. We selected 27 full text articles including 16 randomized clinical trials, 7 systematic reviews, and 4 guidelines. Quality of each studies were evaluated by the Cochran's Risk of Bias, AMSTAR, K-AGREEII. Among the studies, 11 studies were excluded.(3) The strength of recommendations were classified and quality of recommendations were ranked.(4) Guideline draft was finalized.(5) Content-validation was conducted by an expert group. All contents were ranked above 0.8 in CVI. Results: Evidence-based clinical practice guideline to prevent CIN was dveloped.(1) The guideline for preventing CIN recommends using 0.9% saline.(2) Standardized rate of fluid therapy is 1 to 1.5ml/kg/hr.(3) Execute hydration for 6~12hrs before PCI and after PCI. Conclusion: This study suggests evidence-based clinical practice guideline for preventing CIN which can be more efficiently used in clinical practice.

• 대한한방내과학회지
• /
• 제44권3호
• /
• pp.387-401
• /
• 2023

Objective: This study was conducted to investigate the preventive effect of herbal medicines on restenosis after percutaneous coronary intervention (PCI) by reviewing randomized controlled trials (RCTs). Methods: RCTs were searched for herbal medicine treatment after PCI using eight online databases (PubMed, CNKI, Wanfang, J-STAGE, OASIS, ScienceON, KTKP, and KISS). Studies that confirmed restenosis through coronary angiography at follow-up were selected according to the inclusion and exclusion criteria. The primary outcome was the restenosis rate, and the secondary outcome was the angina recurrence rate. Data were extracted from the final selected studies according to the research methodology and then analyzed with Review Manager 5.4.1. Study quality was assessed using Cochrane's risk-of-bias (RoB) tool. Results: Of the 252 papers obtained through the primary search, nine studies that met the selection criteria were finally selected. In these nine studies, herbal medicine combined with western medicine was used for the experimental group, and western medicine treatment was used alone for the control group. The meta-analysis result revealed that the restenosis rate and angina recurrence rate were significantly lower in the experimental group than in the control group (RR=0.34, 95% CI: 0.22-0.53, p<0.00001, I²=0% and RR=0.47, 95% CI: 0.29-0.78, p=0.004, I²=0%, respectively). Furthermore, the quality of studies assessed by Cochrane's RoB was low. Conclusions: This study showed that the combined treatment of herbal medicine and western medicine was effective in preventing restenosis and angina after PCI. As the number of papers included in this study was small, a large number of high-quality clinical studies should be considered in the future.

• 한국임상약학회지
• /
• 제22권2호
• /
• pp.113-122
• /
• 2012

ACC/AHA/SCAI Guideline recommends for administration dual antiplatelet therapy after drug-eluting stent (DES) to prevent restenosis and stent thrombosis in patients with percutaneous coronary intervention (PCI). Recently triple antiplatelet therapy including cilostazol is known to reduce restenosis and stent thrombosis significantly after DES implantation. However, there is lack of data providing the efficacy of triple antiplatelet therapy. The purpose of this study is to evaluate the clinical effects of the triple therapy after DES implantation compared with the dual therapy. This retrospective study collected data from medical charts of 251 patients who received DES implantation between Jul 2006 and Jun 2008. They received either dual antiplatelet therapy (N = 154 clopidogrel and aspirin; Dual group) or triple antiplatelet therapy (N = 97 cliostazol, clopidogrel and aspirin; Triple group). Major adverse cardiac event rates (MACE, included total death, myocardial infarction, target lesion revascularization) at 12 months, 24 months, stent thrombosis, rates of bleeding complications and adverse drug reactions were compared between these two groups. Compared with the dual group, the triple group had a similar incidence of the MACE rates at 24months (12.3% vs. 12.4%, p = 0.99). There is no difference in overall stent thrombosis between two groups (Dual group 2.6% vs. Triple group 4.1%, p = 0.5). Subgroup analysis showed that diabetic patients got more benefit in reducing MACE rates but, there is no statistical difference. Bleeding complications and adverse drug effects were not different significantly. As compared with dual antiplatelet therapy, triple antiplatelet therapy did not reduce the 12-months, 24-months MACE rates and stent thrombosis. Bleeding complications and adverse drug effects were not different.

• 대한한방내과학회지
• /
• 제42권2호
• /
• pp.184-196
• /
• 2021

Objectives: This case report presents the effects of Korean medical treatment in a patient with chest pain after percutaneous coronary intervention (PCI). Methods: An 80-year-old woman was treated with Korean herbal medicine, acupuncture, and cupping therapy. Chest pain, sore tongue, and headache were assessed daily using a numeric rating scale (NRS). Results: After 15 days of treatment, chest pain disappeared, as reflected by an NRS change from 9 to 0, and headache was relieved (NRS decreased from 9 to 2). On the eighth day of treatment, the sore tongue was also relieved, as reflected by an NRS change from 9 to 0. Conclusion: These results show that chest pain after PCI can be relieved with Korean medical treatment, and it is expected that major adverse cardiac events (MACEs) may be prevented with Korean medical treatment. However, additional well-designed studies are required to confirm these findings.