• 제목/요약/키워드: LIAO

검색결과 440건 처리시간 0.022초

2D 원통형 좌표계를 위한 FDTD 방법에서 UPML과 Liao 흡수경계조건의 비교 (Comparisons between UPML and Liao's ABC in the FDTD method for 2D Cylindrical Coordinates)

  • 홍익표
    • 한국정보통신학회논문지
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    • 제11권6호
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    • pp.1054-1061
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    • 2007
  • 본 논문에서는 2D 원통형 좌표계 구조를 해석하기 위한 전자기 수치 해석 방법 중 하나인 시간영역 유한차분법(FDTD)에서 필요한 흡수경계조건으로 UPML과 Liao 흡수경계조건을 비교하였다. 일반적인 2D 직각 좌표계에서는 UPML의 성능이 Liao의 흡수경계조건보다 우수하지만, 본 논문에서 가정한 2D 원통형 좌표계에서는 Liao에 의해 제안된 고유의 흡수경계조건이 UPML과 수정된 Liao 흡수경계조건보다 우수한 것으로 나타났다. 원통형 좌표계는 축에 대해서 대칭이기 때문에 3D 구조를 2D 구조로 가정할 수 있다는 점에서 안테나를 비롯한 다양한 마이크로파 회로의 특성해석에 널리 사용될 수 있는데, 정확한 수치해석 결과를 얻기 위해서 다양한 구조에 대한 흡수경계조건들의 비교와 검증이 필요하다.

멀티서버를 위한 안전한 동적 ID 기반 원격 사용자 인증 방식에 대한 안전성 분석 (Security Analysis of a Secure Dynamic ID based Remote User Authentication Scheme for Multi-server Environment)

  • 양형규
    • 한국인터넷방송통신학회논문지
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    • 제13권1호
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    • pp.273-278
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    • 2013
  • 최근에, 멀티서버 환경을 위한 스마트 카드를 이용한 사용자 인증 방식이 실질적인 응용 분야에서 적용되고 있다. 2009년도에 Liao-Wang은 멀티서버를 위한 안전한 동적 ID 기반 원격 사용자 인증 방식을 제안하였다. 이 방식은 여러 종류의 가능한 공격에 안전하면서 사용자 익명성 보장하였다. 본 논문에서 우리는 Liao-Wang의 방식에 대한 안정성을 분석하고, Liao-Wang의 방식이 위조 공격, 패스워트 추측 공격, 세션키 공격 그리고 내부자 공격에 취약하다는 것을 보여준다. 추가로 Liao-Wang의 방식이 사용자와 서버간의 사용자 익명성 역시 제공하지 못한다는 것을 증명한다.

Intentional Identities: Liao Women's Dress and Cultural and Political Power

  • SHEA, Eiren L.
    • Acta Via Serica
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    • 제6권2호
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    • pp.37-60
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    • 2021
  • Before the tenth century, the dress of elite women in and around China often reflected "Han" Chinese fashions and preferences. In funerary paintings and relief sculptures of Sogdian and Xianbei couples from the sixth century, for example, women wear "Han" Chinese-style clothing. Even in the Tang dynasty (ca. 618-907), when exchange with Central Asia via overland Silk Road trade impacted the styles and patterning of elite dress and men incorporated clear Central Asian attributes into their dress, elite women in the Tang sphere wore recognizably Tang fashions. Chinese-style dress in these centuries clearly conveyed cultural import and, likely, political power, especially after the founding of the Tang dynasty. However, the straightforward borrowing of Tang women's dress shifted in the Khitan Liao dynasty (ca. 907-1125). The Liao, in contrast to other states that shared a border with China in previous centuries, saw themselves as political equals to the Song dynasty (ca. 960-1278) court in the south. The Liao court was interested in Song customs and culture and incorporated artistic motifs and practices from the Song court. However, the Liao courtly idiom was never fully subsumed into the greater world of the Song - rather, the Liao used facets of Song courtly culture for their own ends. One way this is manifested is through the dual administrative system, a bureaucratic organization that, among other things, regulated and distinguished between who was permitted to wear Khitan and non-Khitan dress. In this paper, I will examine the material evidence from funerary contexts for how the dress of elite Liao women both engaged with the dress of the Song, while also maintaining a certain amount of cultural autonomy. Through their dress, elite Liao women signaled clear messages about their status, identity, and difference to their Song counterparts.

Tool Planning in Assembly Simulation and its Application

  • Liao, Huafei;Zhang, Linxuan
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.55.6-55
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    • 2002
  • Huafei Liao is a graduate student of the Automation department in Tsinghua University, China. His research involves computer-aided process planning, 3D CAD/CAM, virtual reality, and feature recognition.

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The Khitans: Corner Stone of the Mongol Empire

  • LANE, GEORGE
    • Acta Via Serica
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    • 제6권1호
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    • pp.141-164
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    • 2021
  • The Khitans were a Turco-Mongol clan who dominated China north of the Yangtze River during the early mediaeval period. They adopted and then adapted many of the cultural traditions of their powerful neighbours to the south, the Song Chinese. However, before their absorption into the Mongol Empire in the late 13th century they proved pivotal, firstly in the eastward expansion of the armies of Chinggis Khan, secondly, in the survival of the Persian heartlands after the Mongol invasions of the 1220s and thirdly, in the revival and integration of the polity of Iran into the Chinggisid Empire. Da Liao, the Khitans, the Qara Khitai, names which have served this clan well, strengthened and invigorated the hosts which harboured them. The Liao willingly assimilated into the Chinggisid Empire of whose formation they had been an integral agent and in doing so they also surrendered their identity but not their history. Recent scholarship is now unearthing and recognising their proud legacy and distinct identity. Michal Biran placed the Khitans irrevocably and centrally in mediaeval Asian history and this study emphasises their role in the establishment of the Mongol Empire.

개천절 일자(日字)와 단군조선 개국년도 문제 고찰과 제언 (DATING ISSUE OF THE NATIONAL FOUNDATION DAY OF KOREA)

  • 박창범
    • 천문학논총
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    • 제30권1호
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    • pp.1-9
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    • 2015
  • The National Foundation Day of Korea (개천절, 開天節) is currently celebrated on October 3 in Gregorian calendar. We review the history of dating the National Foundation Day of Korea and make a suggestion that it be celebrated on October 3 in the lunar calendar. We present numerous historical records on heaven-worship rites supporting the date October 3 in the lunar calendar. It is pointed out that October 3 in the solar calendar has been adopted in 1949 by the National Assembly with the thought that the lunar calendar is inferior and behind the times. The thought originates from misunderstanding on the value of the lunar calendar and from the ignorance of importance of history and tradition. Since there are now many national holidays that follow the lunar calendar, the logic of the National Assembly in 1949 also makes no sense. We emphasize that the lunar calendar should be followed for the National Foundation Day of Korea for its historical and symbolic characteristics restoration. We also investigate the year of the foundation of the first country of Korea, Dangun Joseon. It is found that even though the majority of the literature before late 15th century recorded the beginning year of Dangun Joseon dynasty to be equal to that of Liao Dynasty (堯), it was accidentally changed to the 25th year of Liao Dynasty in 1484 through a misinterpretation of the previous records. We claim that the beginning year of Dangun Joseon should be set to that of Liao Dynasty as recorded in the original literature in the earlier days. According to the two main opinions accepted by Korea, the beginning year of Liao Dynasty was 2357 B.C. or 2333 B.C., which correspond to the year of Gap-Jin (the 41st year of the sexagenary cycle) or Mu-Jin (the 4th year of the sexagenary cycle), respectively.

스마트카드를 이용한 사용자 인증 스킴의 안전성 분석 및 개선 (Cryptanalysis and Enhancement of a Remote User Authentication Scheme Using Smart Cards)

  • 이영숙;원동호
    • 한국컴퓨터정보학회논문지
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    • 제15권1호
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    • pp.139-147
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    • 2010
  • 사용자 인증 스킴은 개방된 통신환경에서 원격지에 있는 사용자가 서버에 로긴할 때 정당한 사용자 인지를 확인하는 것이다. 2005년 Liao등은 스마트 카드를 이용해서 사용자의 익명성을 보장하는 사용자 인증 스킴을 제안하였다. 최근 Yoon등은 Liao가 제안한 사용자 인증 스킴의 안전성 분석을 수행한 후 그 스킴에 존재하는 결점을 보완하는 향상된 스킴을 제안하였다. 그러나 안타깝게도 그들이 제안한 스킴은 사용자가 서버를 인증하는 방식과 서버가 사용자를 인증 방식을 모두 수행할 수 없고 패스워드의 안전성에도 문제점이 존재한다. 이러한 문제점을 이 논문에서는 서버 가장 공격, 사용자 가장 공격, 오프라인 사전공격을 수행하여 지적하였다. 아울러 본 논문에서는 Yoon등이 제안한 논문의 취약점을 제거하여 보다 안전한 사용자 인증 스킴을 제안하였다.

료(遼).금(金).원대(元代)의 의정사(醫政史)에 관한 연구 (A Study of the History of Medical Administration for Liao(遼).Jin(金).Yuan(元) Dynasty)

  • 김기욱;박현국
    • 대한한의학원전학회지
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    • 제20권1호
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    • pp.17-37
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    • 2007
  • Basic summary of the medical administration: First of all, Liao Jin Yuan dynasties had broad cultural exchange between north and south that the two traditional medical administrations were closely linked which later formed a system that united as one. Establishment of governmental medical office and governmental medical education organization was the very first attempt in the history of the medical administration. The measure on promoting the social level of medical doctors has an important meaning on the growth of the medical field. Medical policy on prisoners was done under the new condition brought on from experience. Medicine not of China was broadly interchanged, medicine from Arab was spread throughout China, and the department on skeletal injuries and the dietary treatments had major development. At this era, under a overall expansion of politics, economy, culture and medicine, scholastic dispute on medicine triggered medical expansion.

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중국 요하 하류부 고대 요택의 공간 분포와 Holocene 중기 이후 해안선 변화 (The Spatial Distribution of the Ancient Liaoze in the Lower Reach of Liao River and Shoreline Change Since the Middle Holocene in China)

  • 윤순옥;김효선;지아지엔칭;복기대;황상일
    • 한국지형학회지
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    • 제24권1호
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    • pp.51-62
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    • 2017
  • Liao River with the largest basin area in the northeastern part of China has constructed huge floodplain along the lower reach. Especially a vast marsh was developed around estuaries and coastline near Liaodong Bay. The marsh was called as Yotaek(or Liaoze) before the modern time, which is meaningful for understanding human life since prehistorian times. By the analysis of historical documents and geomorphic data, it can be assumed that the height of Yotaek of landward boundary reached 20~30m from Heishan to Liaoyang during Han dynasty. The shoreline of 7,000 yr BP is estimated to coincide with the contour line between 20m and 30m at present. And the ancient shoreline during Christ era indicates 10m.a.s.l., which is corresponding to the seaside boundary of the Yotaek. The shoreline of Liaodong Bay was progressed seaward 30km/ka during 1000~1100 AD, while 10~40km/ka during late 19 century ~ early 20 century.