아테네 헌장(1931)의 재고

최병하,Choi, Byung-Ha 한국건축역사학회 2012 건축역사연구 Vol.21 No.4

This paper is to review the conclusions of the Athens conference that has so far contributed to the conservation world. It is normally called the conclusions of the Athens conference as the Athens charter. But the conclusions of the Athens are not as same as the Athens Charter regarding the contents. The former had more valuable contents than the latter regarding historic monuments. And the report of the Athens conference including 56 articles and 500 pages with 55 photos was published in 1933 by the International Museums Office. But little attention has been given to the report of the Athens conference. Therefore the point I want to make is to review to the report in order to understand the agenda of the conference and to examine the Anastylosis in Acropolis. In conclusion, these agendas and the articles in the report show us that the conference was sort of milestone with some advanced modern philosophical and technical concepts about conservation and restoration of historic monuments. Also when the term of anastylosis turns to reconstruction in archaeological sites, we are going to face with the problems of authenticity.

크메르 종교건축에서 회랑의 의미와 구법 발전에 관한 연구

최병하(Choi, Byung-Ha) 대한건축학회 2012 대한건축학회논문집 Vol.28 No.3

One of the most unique architectural particularities in the Khmer monument is the gallery, appearing from about 11 century in the Khleang style of the Khmer architectural history. The architectonic evolution regarding the corbel arch, window, and connective beam in a gallery indicates the identity of the Angkor monuments, nevertheless earlier studies have lacked such architectonic viewpoints. In this paper each phase of the architectonic evolution and its spatial meaning is looked at with several monuments in the Angkor archeological site. In conclusion, this paper indicates the followings. Firstly the appearance of a gallery is not derived from the long-buildings around the sanctuary but from the new ideas giving symbolism of Meru and keeping the spatial holiness of the site. Secondly a closed space with a gallery was changed into an open space in mountain-monument type in later times, and it proves the discovery of the new conception by Khmer architects in terms of landscape. Finally the architectonic concepts of a gallery derive mostly from wooden architectonics. When faced with technical problems in masonry work, it is likely that Khmer architects overcame the architectonic difficulties in view of the wooden architectural concept and techniques.

HTTP Outbound Traffic에 HMM을 적용한 웹 공격의 비정상 행위 탐지 기법

최병하(Byung-Ha Choi),최승교(Sung-Kyo Choi),조경산(Kyung-San Cho) 한국컴퓨터정보학회 2012 韓國컴퓨터情報學會論文誌 Vol.17 No.5

본 논문은 HTTP Outbound Traffic의 감시를 통해 다양한 웹 공격의 침입 경로에 대응하고, 학습 효율성을 높여 변종 또는 새로운 기법을 이용한 비정상 행위에 대한 오탐을 낮춘 기법을 제안한다. 제안 기법은 HMM(Hidden Markov Model)을 적용하여 HTML 문서속의 태그와 자바스크립트의 학습을 통한 정상 행위 모델을 생성한 후, HTTP Outbound Traffic속의 정보를 정상 행위 모델과 비교하여 웹 공격을 탐지한다. 실제 침입된 환경에서의 검증 분석을 통해, 제안기법이 웹 공격에 대해 0.0001%의 오탐율과 96%의 우수한 탐지능력을 보임을 제시한다. In this paper we propose an anomaly detection scheme to detect new attack paths or new attack methods without false positives by monitoring HTTP Outbound Traffic after efficient training. Our proposed scheme detects web-based attacks by comparing tags or javascripts of HTTP Outbound Traffic with normal behavioral models which apply HMM(Hidden Markov Model). Through the verification analysis under the real-attacked environment, we show that our scheme has superior detection capability of 0.0001% false positive and 96% detection rate.

아나스티로시스의 도입에 대한 의혹

최병하(Choi, Byung-Ha) 대한건축학회 2012 대한건축학회논문집 Vol.28 No.7

This paper is to indicate some doubts on the established story that Henri Marshal, Angkor monument conservator, had introduced Anastylosis as reconstruction in Angkor monuments from the Oudheidkundige Dienst in Nederlandsch-Indie’s reconstruction activities during the 1920s to 1930s and to consider the cause of some doubts. With faced with the limit of conservation activities in Angkor monument, the EFEO missioned Henri Marchal, conservator of Angkor monument, to Java in 3 months in order to study the ODNI’s reconstruction which had been obtaining an expected result in Java. After his returning, Henri Marchal started the first reconstruction at Banteay Srei in Angkor monuments, and insisting on his first reconstruction as anastylosis introduced from Java. But, Here, I could rise up a series of doubt that the ODNI didn’t use the term of anastylosis in Java at those times, and in fact the term will be proposed by an greek conservator, Nicolas Baranos, and authorized in the Athena conference in 1931 later also after starting the first reconstruction of Banteay Srei. In conclusion, Henri Marchal would like intentionally to use the term of anastylosis to get a good evaluation on his first reconstruction and to escape from a possible conflict of reconstruction in the near future.

개발 생산성 향상을 위한 분산 시스템 기반의 프레임워크 설계

최병하(Byung-Ha Choi),최승교(Sung-Kyo Choi),조경산(Kyung-San Cho) 한국컴퓨터정보학회 2012 韓國컴퓨터情報學會論文誌 Vol.17 No.1

본 논문은 분산 시스템 기반에서 경량급 프레임워크의 간단한 개발 주기를 지원하며 분산 처리가 가능한 IPO(Input-Process-Output) 모델 기반의 프레임워크를 제안한다. 제안 프레임워크는 입력 함수, 처리 함수, 출력 함수를 가진 클래스를 개발하면 분산 시스템의 표현 계층과 중간 계층에서 하나의 응용 프로그램으로 실행되도록 지원해준다. 또한 이 기법의 특징으로 응용 프로그램 개발시 분산 시스템 의존적인 부분을 제거하며, 개발-구축-배치-검증의 개발 주기를 개발-검증 주기로 감소시킨다. 이 기법의 생산성 향상과 성능 검증하기 위해 기존의 분산 시스템과 경량급 프레임워크의 응용 프로그램을 제안 기법의 응용 프로그램과 비교 분석한다. 그 결과 상당한 코드 감소와 분산 시스템 의존적인 부분이 감소하여 개발 생산성을 향상시키고 경량급 시스템에 비해 상대적으로 안전적인 성능을 보인다. In this paper, we propose a framework which supports the simple development cycle based on Distributed System using IPO(Input-Process-Output) model. In our proposed framework, once a single class with Input, Process and Output functions is developed, it can be executed like a single application in both presentation layer and middle layer of a distributed system. Our proposed Framework removes dependency on distributed system and makes development cycle decreased from Develop-Build-Deploy-Test cycle to Develop-Test cycle when application programs is developed. The verification of productivity and performance is performed by comparing our Framework with distributed system or lightweight Framework. The results show high productivity due to the considerable amount of reduction in lines of source code and reduction in dependency on distributed system, and show stabler performance than lightweight framework.

전단 유동 하에서 전기유변유체의 과도응답 특성

최병하(Byung-Ha Choi),남윤주(Yun-Joo Nam),박명관(Myeong-Kwan Park) 대한기계학회 2009 大韓機械學會論文集B Vol.33 No.6

The transient shear stress response of an electrorheological fluid is investigated experimentally. The characteristic time constants of an electrorheological fluid sheared between two concentric cylinders were obtained under various electric field strengths and shear rates. Also, two experimental modes are adopted to investigate the effect of the shear flow on the dynamic behavior of the fluid; one is that the electric field is induced before shearing, and the other is the electric field is induced after shearing. From the difference in the response time between two modes, the cluster formation time were obtained. The response times were decreased with the increase of the shear rate, irrelatively of the electric field strength. The cluster formation time were monotonically increased with increase of shear rate, and thereafter, were converged with a certain value.

크메르 기념물에 나타난 지붕구조의 변천에 관한 고찰

최병하(Choi Byung-Ha) 대한건축학회 2009 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.29 No.1(계획계)

There are a lot of monuments, in the Angkor archeological site, constructed as the royal capital by the Khmer empire during 9-15century. One of architectural techniques in Khmer monument when the roof constructed, is to be adopted a corbel arch. The evolution of technique regarding a corbel arch would be related with the change of architectural material as well as ideas of stonecraft. Although such each stance of evolution indicates the icon of architectural technique, this point of view is limited and lack of systematization because theses on Khmer monument, up to now, have mainly focused in artistic style in order to solve the problem of chronicle in Khmer art history. Therefore here I would like to introducing each stance of the technical evolution concerning the roof structure of some monuments located in the Angkor site and furthermore considering the architectural meaning inside Khmer monument.

HTTP Outbound Traffic을 이용한 개선된 악성코드 탐지 기법

최병하(Byung-Ha Choi),조경산(Kyung-San Cho) 한국컴퓨터정보학회 2009 韓國컴퓨터情報學會論文誌 Vol.14 No.9

웹을 통해 유포되는 악성코드는 다양한 해킹 기법과 혼합되어 진화되고 있지만, 이의 탐지 기법은 해킹 기술의 발전과 신종 악성코드에 제대로 대응하지 못하고 있는 실정이다. 본 논문에서는 악성코드와 이의 유포 특성의 분석에 따라 탐지 시스템이 갖추어야 할 요구사항을 정의하고, 이를 기반으로 HTTP Outbound Traffic을 감시하여 악성코드의 유포를 실시간으로 탐지하는 개선된 탐지 기법을 제안한다. 제안 기법에서는 악성코드를 유포하는 것으로 입증된 HTML 태그와 자바스크립트 코드를 시그니쳐로 IDS에 설정한다. 실제 침입된 환경에서의 검증 분석을 통해 제안 기법이 기존 기법에 비해 요구 사항의 만족에 우수하고 악성코드에 대한 높은 탐지율을 보임을 제시한다. Malicious codes, which are spread through WWW are now evolved with various hacking technologies However, detecting technologies for them are seemingly not able to keep up with the improvement of hacking and newly generated malicious codes. In this paper, we define the requirements of detecting systems based on the analysis of malicious codes and their spreading characteristics, and propose an improved detection scheme which monitors HTTP Outbound traffic and detects spreading malicious codes in real time. Our proposed scheme sets up signatures in IDS with confirmed HTML tags and Java scripts which spread malicious codes. Through the verification analysis under the real-attacked environment, we show that our scheme is superior to the existing schemes in satisfying the defined requirements and has a higher detection rate for malicious codes.

HTTP Outbound Traffic 감시를 통한 웹 공격의 효율적 탐지 기법

최병하(Byung-Ha Choi),최승교(Sung-Kyo Choi),조경산(Kyung-San Cho) 한국컴퓨터정보학회 2011 韓國컴퓨터情報學會論文誌 Vol.16 No.1

웹 기반 공격에 대한 대응책으로 계층적 웹 보안 시스템이 있지만 다양한 혼합 및 우회 공격에는 제대로 대응하지 못하는 실정이다. 본 논문은 웹 공격에 의해 발생하는 악성코드 유포, XSS, 웹쉘 생성, URL Spoofing, 개인 정보유출 등의 증상을 HTTP outbound traffic의 감시를 통해 실시간으로 탐지하는 효율적인 기법을 제안한다. 제안 기법은 다양한 웹 공격에 의해 생성되는 HTML 태그와 Javascript 코드를 분석하여 설정한 시그너처를 outbound traffic과 비교 검색하여 웹 공격을 탐지한다. 실제 침입 환경에서의 검증 분석을 통해, 계층적 보안 시스템과 결합된 제안기법이 우회된 웹 공격에 대한 탐지능력이 탁월함을 보인다. A hierarchical Web Security System, which is a solution to various web-based attacks, seemingly is not able to keep up with the improvement of detoured or compound attacks. In this paper, we suggest an efficient detecting scheme for web-based attacks like Malware, XSS, Creating Webshell, URL Spoofing, and Exposing Private Information through monitoring HTTP outbound traffics in real time. Our proposed scheme detects web-based attacks by comparing the outbound traffics with the signatures of HTML tag or Javascript created by the attacks. Through the verification analysis under the real-attacked environment, we show that our scheme installed in a hierarchical web security system has superior detection capability for detoured web-based attacks.

전단 유동을 하는 전기유변 유체의 동적 응답에 입자 응집이 미치는 영향

최병하(Byung-Ha Choi),남윤주(Yun-Joo Nam),박명관(Myeong-Kwan Park) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

In this study, the effect of particle aggregation on dynamic response time of Electrorheological (ER) fluid is investigated. The particle aggregation time is defined as the time interval between the application of the field and the formation of the first chain bridging the two electrodes. The dynamic response times of an ER fluid sheared between two concentric cylinders have been obtained under two different experimental conditions: the one is that the electric field is induced before shearing, and the other is that the electric field is induced after shearing. From the difference between two response times, the particle aggregation times are determined under various electric fields and shear rates. The experimental results show that the aggregation rate is decreased with an increase of shear rate, while electric field has little effect on it. Therefore, it is verified that the hydrodynamic force hinders the formation of chain-like structures.