• International journal of advanced smart convergence
• /
• 제7권4호
• /
• pp.161-168
• /
• 2018

Recently, the bio-sensing information systems for collecting and analysing human body information of a patient in real time in the field of medical information and healthcare information service are continuously increasing. Specially, various wearable devices such as a wrist, a garment, and a skin attachment type for supporting health information of a mobile user are rapidly increasing. Until now, there is no patch-type biometric information service model. Therefore, this paper presents a biometric information system model and the application examples to support biometric information sensing and health information service of mobile user with digital patch system as a new biometric information system. As a result, through this research, research issues based on digital patch system are searched to suggest the direction of continuous research.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
• /
• pp.397-400
• /
• 2001

In this paper, to improve bandwidth of microstrip antenna, we discussed the patch structure using Aperture Stacked Patch. To provid PCS service and IMT-2000 service simultaneous, a microstrip patch antenna needs impedance bandwidth of 22%. But typical microstrip patch antennas have impedance bandwidth of 3∼6%. To analyze characteristics of microstrip pach antenna, we used Ensemble of commercial software. The microsrtip patch antenna was designed and fabricated, tuned. We get following results; 650MHz(33%) of impedance bandwidth for VSWR 1.5. The measured gain of ASP microstrip antenna is 6.94dBi.

• 대한전자공학회논문지TC
• /
• 제39권2호
• /
• pp.108-116
• /
• 2002

본 논문은 프로브 피드와 이중 패치 구조를 이용한 마이크로스트립 안테나 대역폭 개선에 관한 것이다. PCS와 IMT-2000 서비스를 동시에 제공하기 위한 안테나는 임피던스 대역폭이 22%가 되어야 한다. 본 논문에서는 구조가 복잡하지 않는 광대역 마이크로스트립 패치 안테나에 대해 제안한다. 마이크로스트립 패치 안테나의 특성 해석은 상업용 소프트웨어인 앙상블을 이용하였다. 마이크로스트립 패치 안테나의 설계, 제작 및 보정한 결과 값은 VSWR 2에서 임피던스 대역폭이 500 ㎒(25.5%), VSWR 1.5에서 임피던스 대역폭이 430 ㎒(21.9%)의 결과를 얻었다. 안테나의 복사패턴에서 부엽(side lobe)은 -14 dB를 가졌고, 전후방비(front to back ratio)는 전체적으로 20 dB를 얻었다. 안테나의 측정 이득은 5.2 dBi이다.

• Journal of Information Processing Systems
• /
• 제16권2호
• /
• pp.301-317
• /
• 2020

An enterprise patch-management system (PMS) typically supplies a single point of failure (SPOF) of centralization structure. However, a Blockchain system offers features of decentralization, transaction integrity, user certification, and a smart chaincode. This study proposes a Hyperledger Fabric Blockchain-based distributed patch-management system and verifies its technological feasibility through prototyping, so that all participating users can be protected from various threats. In particular, by adopting a private chain for patch file set management, it is designed as a Blockchain system that can enhance security, log management, latest status supervision and monitoring functions. In addition, it uses a Hyperledger Fabric that owns a practical Byzantine fault tolerant consensus algorithm, and implements the functions of upload patch file set, download patch file set, and audit patch file history, which are major features of PMS, as a smart contract (chaincode), and verified this operation. The distributed ledger structure of Blockchain-based PMS can be a solution for distributor and client authentication and forgery problems, SPOF problem, and distribution record reliability problem. It not only presents an alternative to dealing with central management server loads and failures, but it also provides a higher level of security and availability.

• 한국컴퓨터정보학회논문지
• /
• 제22권4호
• /
• pp.67-74
• /
• 2017

The objective of this paper is to design broadband microstrip patch antenna for mobile communication service. The enhanced features were confirmed and proved by comparing the proposed antenna with the antennae that have been reported in the relevant literatures. The experimental results show that the impedance bandwidth(VSWR ${\leq}2$) of 19.6%(fo=1,920MHz) and the peak gain of 5.53dBi(at 1,900MHz) were obtained by the mobile communication service frequency band. The proposed antenna had the impedance bandwidth of about 3.1% larger than that of the reported microstrip antenna.

• 대한기계학회논문집A
• /
• 제24권8호
• /
• pp.2000-2006
• /
• 2000

The enhancement of service life of damaged or cracked structures is currently major issue to the researchers and engineers. In order to improve the life of cracked aging aircraft structures, the repair technique which uses adhesively bonded boron/epoxy composite patches is being widely considered as a cost-effective and reliable method. This paper is to study the performance of the bonded composite patch repair of a plate containing an inclined central through-crack. A 3-dimensional finite element method having three layers to the cracked plate, composite patch and adhesive layer, is used to compute the stress intensity factor. In this paper, the reduction of stress intensity factors near the crack-tip are determined to evaluate the effects of various non-dimensional design parameter including composite patch thickness, and material properties of the composite patch and thickness of the adhesive layer, materials of patch etc., and the crack length, Finally, The problem of how to optimize the patch geometric configurations has been discussed.

• 정보보호학회논문지
• /
• 제28권6호
• /
• pp.1393-1399
• /
• 2018

다양한 소프트웨어를 사용하는 기업은 보안 업체에서 제공하는 패치관리시스템을 사용하여 소프트웨어의 취약점을 일괄적으로 관리해서 보안 수준을 높인다. 시스템 관리자는 최신 소프트웨어 버전을 유지하기 위해 신규 패치 정보를 제공하는 벤더 사이트를 모니터링 하지만 패치를 제공하는 주기가 불규칙적이고 웹 페이지 구조가 다르기 때문에 패치 정보를 검색하고 수집하는데 많은 비용과 모니터링 시간이 소요된다. 이를 줄이기 위해 키워드나 웹 서비스를 기반으로 패치 정보 수집을 자동화하는 연구가 진행되었으나 벤더 사이트에서 패치 정보를 제공하는 구조가 규격화되어 있지 않기 때문에 특정 벤더 사이트에서만 적용 가능했다. 본 논문에서는 패치 정보를 제공하는 벤더 사이트 구조와 특징을 분석하고 패치 정보 수집에 소모되는 비용과 모니터링 시간을 줄이기 위해서 웹 크롤러를 이용해 패치 정보 수집을 자동화하는 시스템을 제안한다.

• Steel and Composite Structures
• /
• 제32권1호
• /
• pp.127-139
• /
• 2019

Bridges, offshore oil platforms and other infrastructures usually require at some point in their service life rehabilitation for reasons such as aging and corrosion. This study explores the application of adhesively bonded CFRP patches in repair of corroded circular hollow sectional (CHS) steel beams. An experimental program involving three-point bending tests was conducted on intact, corroded, and repaired CHS beams. Meso-scale finite element (FE) models of the tested beams were developed and validated by the experimental results. A parametric study using the validated FE models was performed to examine the effects of different CFRP patch parameters, including patch dimensions, number of plies and stacking sequence, on efficiency of the repair system. Results indicates that the corrosion reduced elastic stiffness and flexural strength of the undamaged beam by 8.9 and 15.1%, respectively, and composite repair recovered 10.7 and 18.9% of those, respectively, compared to undamaged beam. These findings demonstrated the ability of CFRP patch repair to restore full bending capacity of the corroded CHS steel beam. The parametric study revealed that strength and stiffness of the repaired CHS beam can be enhanced by changing the fiber orientations of wet composite patch without increasing the quantity of repair materials.

• 한국컴퓨터정보학회논문지
• /
• 제27권1호
• /
• pp.33-41
• /
• 2022

본 논문은 유전체 기판 상에 설계한 평면형 마이크로스트립 패치 안테나를 기술하였다. 5세대 이동통신 적용을 위하여 2가지 타입의 평면형 마이크로스트립 패치 안테나를 연구하였으며 한 타입은 일반적인 마이크로스트립 구조이며 다른 한 타입은 동축 프로브 급전의 적층된 마이크로스립 구조이다. 전자기적인 커플링 방식을 사용한 적층된 마이크로스트립 패치는 다층기판 구조에서 설계되었다. 본 논문에서 제안한 적층된 마이크로스트립 패치 안테나는 3.42GHz~3.70GHz 광대역의 5G 서비스 대역에서 양호한 결과를 나타냈다. 임피던스 대역폭(VSWR≤2)은 3.42GHz~3.78GHz에서 360MHz(10.28%)를 나타냈다. 본 논문의 적층된 마이크로스트립 패치 안테나의 설계를 통하여 5G 이동통신 중계 시스템에 적용가능성을 확인하였다.

• Journal of Chest Surgery
• /
• 제49권2호
• /
• pp.85-91
• /
• 2016

Background: This study was conducted to determine the efficacy of staple line coverage using a polyglycolic acid patch and fibrin glue without pleural abrasion to prevent recurrent postoperative pneumothorax. Methods: A retrospective analysis was carried out of 116 operations performed between January 2011 and April 2013. During this period, staple lines were covered with a polyglycolic acid patch and fibrin glue in 58 cases (group A), while 58 cases underwent thoracoscopic bullectomy only (group B). Results: The median follow-up period was 33 months (range, 22 to 55 months). The duration of chest tube drainage was shorter in group A (group A $2.7{\pm}1.2day$ vs. group B $3.9{\pm}2.3day$, p=0.001). Prolonged postoperative air leakage occurred more frequently in group B than in group A (43% vs. 19%, p=0.005). The postoperative recurrence rate of pneumothorax was significantly lower in group A (8.6%) than in group B (24.1%) (p=0.043). The total cost of treatment during the follow-up period, including the cost for the treatment of postoperative recurrent pneumothorax, was not significantly different between the two groups (p=0.43). Conclusion: Without pleural abrasion, staple line coverage with a medium-sized polyglycolic acid patch and fibrin glue after thoracoscopic bullectomy for primary spontaneous pneumothorax is a useful technique that can reduce the duration of postoperative pleural drainage and the postoperative recurrence rate of pneumothorax.