• 한국인터넷방송통신학회논문지
• /
• 제17권1호
• /
• pp.1-11
• /
• 2017

최근 서비스 계약 또는 가입에 개인의 고객정보 이용 및 약관 동의를 위한 디지털 자필 서명을 요구하는 것이 일반적이다. 기존 자필 서명을 포함하는 서명시스템들은 각 기업 내에서 자체적으로 서비스 플랫폼 위에 구현되어 활용되고 있기 때문에 플랫폼에 의존적일 뿐만 아니라 디바이스 보유 현황에 따라 서명을 수행할 수 있는 환경이 달라질 수 있는 문제점이 존재한다. 본 논문에서는 이기종간 통합 브라우저 환경에서 jQuery를 기반으로 자필의 2차원 좌표를 직접 저장하는 방식을 이용하여 크로스 브라우징이 가능한 통합 자필 서명 시스템을 설계 및 구현하였다. iOS, Android, PC 등 이기종 환경의 웹 브라우저에서 통합 테스트를 하였고, 모든 자필 서명 기능이 정상적으로 동작함을 확인하였다.

• Current Optics and Photonics
• /
• 제1권3호
• /
• pp.196-202
• /
• 2017

Corona discharge is always a sign of failure processes of high-voltage electrical apparatus, including those utilized in electric railway systems. Solar-blind ultraviolet (UV) cameras are effective tools for corona inspection. In this work, we present an automatic railway corona-discharge detection system based on solar-blind ultraviolet detection. The UV camera, mounted on top of a train, inspects the electrical apparatus, including transmission lines and insulators, along the railway during fast cruising of the train. An algorithm based on the Hough transform is proposed for distinguishing the emitting objects (corona discharge) from the noise. The detection system can report the suspected corona discharge in real time during fast cruises. An experiment was carried out during a routine inspection of railway apparatus in Xinjiang Province, China. Several corona-discharge points were found along the railway. The false-alarm rate was controlled to less than one time per hour during this inspection.

• 대한치과기공학회지
• /
• 제30권2호
• /
• pp.87-92
• /
• 2008

Purpose: In this study, we tried to compare marginal accuracy when produce ceramic crown using all ceramic materials and existent metal-ceramic system. Material and methods: All-ceramic systems were E-max (Ivoclar/Vivadent, Lichtenstein), Lava(3M, U.S.A.) and Wol-ceram(Teamziereis, Germany). Metal-ceramic system(PFG) was composed of Au-Pt alloy (Metalor, Switzerlandand) and overlying ceramic(D-sign, Ivoclar/Vivadent, Lichtenstein). We fabricated metal master die with upper diameter of 7.95mm, bottom diameter of 9.00mm, height of 5.00mm, and taper of $6^{\circ}$. All ceramic system used 0.5mm thickness ceramic coping, while metalceramic system used 0.3 thickness metal coping. By adding dentin and enamel ceramics on each coping, a crown with a proximal thickness of 1.0 mm and occlusal thickness of 2.0mm was fabricated. Pressure of 2kg was applied for 10 seconds on each crown with static load compressor. Before and after cementation, we measured the marginal gap at 4 points of each crown using optical microscope. The data was analyzed using a Student's t test and repeated-measures of analyses of variance(ANOVA) followed by a Bonferroni test. A p value<0.05 was considered significant. Results: As experiment results, marginal accuracy of wol-ceram and Lava is no good when compared with marginal accuracy of PFG. But marginal accuracy of E.max is good when compared with PFG. This result showed not significant. The marginal accuracy of E.max is good when compared with marginal accuracy of wol-ceram and Lava. Conclusion: The marginal accuracy of E.max is very good when compared with marginal accuracy of another group.

• 한국지반환경공학회 논문집
• /
• 제19권9호
• /
• pp.29-36
• /
• 2018

국내 외에서는 사면붕괴를 사전에 예방할 수 있는 모니터링 및 자동계측기에 관한 다수의 연구가 수행되어져 오고 있으나, 이러한 연구들은 다소 복잡한 구조로 이루어져 있고, 계측시스템의 대부분은 사면표층에 설치되어 있으며, 사면파괴 전 붕괴징후를 사전에 감지하고 경보를 울려주는 계측시스템에 관한 연구는 미진한 실정이다. 본 연구에서는 강우 조건에서의 사면 붕괴 메카니즘을 파악하기 위하여 사면 붕괴 실험을 수행하고 지중 변위와 체적 함수비 계측을 통해 사면 모델의 붕괴 초기에 발생되는 함수비와 변위 거동 특성을 분석하였다. 본 연구를 통해 고찰된 내용은 지방자치단체에서 집중호우로 인해 급경사지 붕괴위험지역 등 사면붕괴나 산사태가 예측될 때 사전에 주민을 대피시키는 사면붕괴 예 경보시스템 구축 시 기초자료로 활용될 수 있을 것으로 기대된다.

• Korean Chemical Engineering Research
• /
• 제58권2호
• /
• pp.184-189
• /
• 2020

Van de Vusse 반응기는 정상상태 입출력 관계에서 최대값을 그리고 이 최대값을 기준으로 동특성의 형태가 크게 바뀌는 특성을 보인다. 운전영역에 따라 정상상태 이득의 부호가 바뀌고, non-minimum phase 동특성 등의 제어를 매우 어렵게 하는 특성들이 나타난다. 매우 많은 비선형제어 방법들과 새로이 고안되고 있는 방법들이 이 Van de Vusse 반응기 공정에 적용되어 그 성능 검증이 이루어지고 있다. 이 반응기의 실제 예가 보고되어 있으나, 화학반응 특성상 제어기 실험에 일상적으로 사용되기에는 어려움이 많아 대부분 모사연구에 그치고 있다. 여기서는 이 Van de Vusse 반응기의 특성을 모두 구현하는 액위시스템을 제작하고, 새로이 고안되는 비선형 제어기의 성능을 밝히는 기준이 될 수 있는 간단한 두 제어 방법의 실험 결과를 제안하고자 한다. 액위시스템 실험장치와 제안된 제어 방법들은 매우 간단하며, 비선형 제어기의 성능과 현장 적용 가능성을 검증하는데 유용하게 사용될 수 있을 것이다.

• Journal of Information Processing Systems
• /
• 제5권1호
• /
• pp.33-40
• /
• 2009

Ever since the network-based malicious code commonly known as a 'worm' surfaced in the early part of the 1980's, its prevalence has grown more and more. The RCS (Random Constant Spreading) worm has become a dominant, malicious virus in recent computer networking circles. The worm retards the availability of an overall network by exhausting resources such as CPU capacity, network peripherals and transfer bandwidth, causing damage to an uninfected system as well as an infected system. The generation and spreading cycle of these worms progress rapidly. The existing studies to counter malicious code have studied the Microscopic Model for detecting worm generation based on some specific pattern or sign of attack, thus preventing its spread by countering the worm directly on detection. However, due to zero-day threat actualization, rapid spreading of the RCS worm and reduction of survival time, securing a security model to ensure the survivability of the network became an urgent problem that the existing solution-oriented security measures did not address. This paper analyzes the recently studied efficient dynamic network. Essentially, this paper suggests a model that dynamically controls the RCS worm using the characteristics of Power-Law and depth distribution of the delivery node, which is commonly seen in preferential growth networks. Moreover, we suggest a model that dynamically controls the spread of the worm using information about the depth distribution of delivery. We also verified via simulation that the load for each node was minimized at an optimal depth to effectively restrain the spread of the worm.

• 동의신경정신과학회지
• /
• 제19권2호
• /
• pp.265-278
• /
• 2008

Stress reaction can be shown widely in the systems of psychology, endocrinology, immunology and so on. Stress promotes catecholamine from the autonomic nerve system, and this activates the sympathetic nerve system. As the sympathetic nerve system is activated, high blood pressure, tachycardia, vertigo, anxiety, diaphoresis, myotonic reaction and others can happen. Autonomic imbalance is the syndrome that people suffer from various symptoms accompanying no organic lesions and no psychological disorders by losing the hormonies between the sympathetic and parasympathetic nerve system. We experienced a 55 year-old female who complained of sudden abdominal pain after being frightened at trouble with her husband. Her abdominal pain was very characteristic, "Something is like rising in my abdomen.", that occurred several times a day. We diagnosed 'Bun-Ton Disease' from her abdominal sign. Several oriental medicine books recorded aspects of Bun-Ton disease and treatments, we had given herbal medicine and treated acupuncture be based on those. Results from studies to date suggest the Bun-Ton Disease's main cause is fright or shock, and they stimulate releasing epinephrine or norepinephrine, that result in various symptoms. In this case report, we will present this patient's case and review the Bun-Ton Disease.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권5호
• /
• pp.1316-1332
• /
• 2012

Formation flying is an important technology that enables high cost-effective organization of outer space aircrafts. The ad-hoc wireless network based on direct-sequence ultra-wideband (DS-UWB) techniques is seen as an effective means of establishing wireless communication links between aircrafts. In this paper, based on the theory of matched filter and error bits correction, a hybrid detection algorithm is proposed for realizing multiuser detection (MUD) when the DS-UWB technique is used in the ad-hoc wireless network. The matched filter is used to generate a candidate code set which may contain several error bits. The error bits are then recognized and corrected by an novel error-bit corrector, which consists of two steps: code mapping and clustering. In the former step, based on the modified optimum MUD decision function, a novel mapping function is presented that maps the output candidate codes into a feature space for differentiating the right and wrong codes. In the latter step, the codes are clustered into the right and wrong sets by using the K-means clustering approach. Additionally, in order to prevent some right codes being wrongly classified, a sign judgment method is proposed that reduces the bit error rate (BER) of the system. Compared with the traditional detection approaches, e.g., matched filter, minimum mean square error (MMSE) and decorrelation receiver (DEC), the proposed algorithm can considerably improve the BER performance of the system because of its high probability of recognizing wrong codes. Simulation results show that the proposed algorithm can almost achieve the BER performance of the optimum MUD (OMD). Furthermore, compared with OMD, the proposed algorithm has lower computational complexity, and its BER performance is less sensitive to the number of users.

• 방송공학회논문지
• /
• 제15권4호
• /
• pp.527-539
• /
• 2010

대부분의 비디오 부호화 시스템은 YCbCr 색 공간에서 부호화가 수행되나 초고화질 비디오가 사용되는 분야에서는 YCbCr 색 공간에서 부호화하는 것이 RGB 색 공간에서 부호화는 것에 비해 높은 압축 효율을 제공하지 않기 때문에 RGB 공간에서 부호화하는 것이 선호된다. RGB 비디오 신호의 압축 부호화 효율을 증대시키기 위하여 본 논문은 잔여신호의 적응적 주파수-선택 가중 예측 기법을 제안한다. RGB 비디오 신호의 색 평면간 상관도를 최대한 활용하기 위해, 제안 기법은 잔여신호 평면 사이의 주파수 영역에서의 부호 일치도와 상관 강도에 근거하여 적응적으로 잔여신호 평면 간 예측될 주파수 영역과 그에 상응하는 예측 가중치를 선택한다. 실험 결과는 최신의 비디오 압축 표준인 H.264/AVC에서 4:4:4 비디오 부호화의 공통 모드에 비해 약 13% 정도 압축 부호화 성능을 개선시켰음을 보여준다.

• 한국정보컨버전스학회:학술대회논문집
• /
• 한국정보컨버전스학회 2008년도 International conference on information convergence
• /
• pp.63-70
• /
• 2008

The authors, Tom Karygiannis of NIST, and Bernard Eydt, Greg Barber, Lynn Bunn, and Ted Phillips of Booz Allen Hamilton, wish to thank Steven Fick, Rick Korchak, Kate Remley, Jeff Guerrieri, Dylan Williams, Karen Scarfone, and Tim Grance of NIST, and Kenneth Waldrop and Beth Mallory of Booz Allen Hamilton. These individuals reviewed drafts of this document and contributed to its technical content. The authors would also like to express their thanks to several experts for their critical review and feedback on drafts of the publication. These experts include V.C. Kumar of Texas Instruments; Simson Garfinkel of the Naval Postgraduate School; Peter Sand of the Department of Homeland Security; Erika McCallister of MITRE; and several professionals supporting Automatic Identification Technology(AIT) program offices within the Department of Defense(DoD), especially Nicholas Tsougas, Fred Naigle, Vince Pontani, Jere Engelman, and Kathleen Smith. During the public comment period we received helpful comments from the following Federal Government agencies: the US Departments of Defense, Health and Human Services, Homeland Security, Labor, and State; the Office of the Director of National Intelligence; the Office of Management and Budget; and the General Services Administration. We also received several helpful contributions from commercial industry, including comments from EPCglobal, VeriSign, and Priway. Finally, the authors wish to thank the following individuals for their comments and assistance: Brian Tiplady, Daniel Bailey, Paul Dodd, Craig K. Harmon, William MacGregor, Ted Winograd, Russell Lange, Perry F. Wilson, John Pescatore, Ronald Dugger, Stephan Engberg, Morten Borup Harning, Matt Sexton, Brian Cute, Asterios Tsibertzopoulos, Mike Francis, Joshua Slob in, Jack Harris, and Judith Myerson.