안전한 리눅스 시스템을 위한 E-BLP 보안 모델과 구현

강정민,신욱,박춘구,이동익,Kang, Jung-Min,Shin, Wook,Park, Chun-Gu,Lee, Dong-Ik 한국정보처리학회 2001 정보처리학회논문지 A Vol.8 No.4

대부분의 안전한 운영체제는 주체와 객체에 보안 등급을 부여하여 운영하는 다중등급 정책(MLP:Multi-Level Policy)을 수용하고 있으며, BLP(Bell and LaPadula) 모델은 이 정책을 표현하는 검증된 대표적인 모델이다. 하지만 BLP 모델을 적용한 안전한 운영체제들은 사용자의 보안 등급을 프로세스에 그대로 상속하고 있음을 알 수 있다. 이러한 접근방법의 문제점은 프로세스를 전적으로 신뢰할 수 없다는 것에서 기인한다. 즉, 사용자의 보안 등급과 권한허용 범위를 오류가 내재되어 있거나 의도적으로 수정된 악의적인(malicious) 프로세스에게 그대로 상속할 경우, 시스템 안전성이 파괴될 가능성이 있다. 이는 BLP 모델이 접근 주체를 정의함에 있어서 시스템 사용자와 실제 그 접근을 대행하는 프로세스를 동일시 하도록 단순하게 정의하고 있기 때문이며, 따라서 사용자와 프로세스간 신뢰관계를 모델에 도입함으로써 해결 가능하다. 또한 다중등급 보안 운영체제들은 접근 주체인 프로세스가 접근 객체로서 존재하는 등급화 된 프로그램 실행 시, 새로운 프로세스를 위한 보안 등급을 부여해야 하는데, 접근 주체와 접근 객체의 보안 등급이 다를 경우, 보안 등급 결정 문제가 발생하며 정보보호의 목적에 위배되는 결과가 발생한다. 이에 본 논문에서는 프로세스의 신뢰성을 고려하고, 보안 등급 결정 문제를 해결할 수 있는 확장된 BLP(E-BLP) 보안 모델을 제안하고 리눅스 커널(2.4.7)에 구현한다. To design and develop secure operating systems, the BLP (Bell-La Padula) model that represents the MLP (Multi-Level Policy) has been widely adopted. However, user\`s security level in the most developed systems based on the BLP model is inherited to a process that is actual subject on behalf of the user, regardless whatever the process behavior is. So, there could be information disclosure threat or modification threat by malicious or unreliable processes even though the user is authorized in the system. These problems can be solved by defining the subject as (user, process) ordered pair and by defining the process reliability. Moreover, when the leveled programs which exist as objects in a disk are executed by a process and have different level from the process level, the security level decision problem occurs. This paper presents an extended BLP (E-BLP) model in which process reliability is considered and solves the security level decision problem. And this model is implemented into the Linux kernel 2.4.7.

임플랜트 Overdenture의 Bar설계에 따른 하악지지조직의 광탄성학적 응력분석

강정민,방몽숙,Kang Jeong-Min,Vang Mong-Sook 대한치과보철학회 1994 대한치과보철학회지 Vol.32 No.2

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

코팅횟수에 따른 PZT세라믹의 구조적 특성

강정민(kang Jeong-Min),조현무(Cho Hyun-Moo),이성갑(Lee Sung-Gap),배선기(Bae Seon-Gi) 대한전기학회 2004 대한전기학회 학술대회 논문집 Vol.2004 No.11

유치원의 아동학대 예방을 위한 환경조사 지표 연구

강정민(Jungmin Kang),강석진(Seokjin Kang) 한국셉테드학회 2020 한국셉테드학회지 Vol.11 No.3

본 연구는 유치원의 아동학대 예방을 위해서 범죄예방디자인 개념을 적용한 현장조사 지표 개발을 목적으로 진행되었다. 유치원의 범죄예방 및 건축계획 기준과 관련된 법제도, 연구, 보고서 등을 고찰한 결과 본 연구와 밀접한 관련이 있는 8개의 자료가 확인되었다. 본 연구에서 도출된 지표구성의 적절성, 개별지표의 중요도 등의 분석을 위해서 범죄예방디자인을 전공했거나 연구 경험이 있는 전문가(건축 6명, 범죄 2명, 유아교육 2명) 10명을 대상으로 2회에 걸쳐 델파이 조사를 진행하였다. 분석결과 아동학대가 주로 실내공간에서 발생하는 점을 고려해야 하고, 범죄예방디자인 원리 및 공간시설계획 요소의 연계가 중요한 것으로 나타났다. 이를 반영하여 최종적으로 3개 영역(공간계획, 안전시설, 교육관리) 45개 지표가 도출되었다. 전문가 조사(AHP 분석 포함)에서 중요도가 높은 것은 감시원리가 반영된 공간 및 시설 관련 지표였고, 영역별 우선순위는 공간계획>안전시설설치>교육관리 순으로 나타났다. 이러한 결과는 아동학대의 문제를 환경적 관점에서 규명하고자 했던 본 연구의 취지와 일치하는 것으로 지금까지 대책으로 제시된 CCTV 설치와는 별개로 환경디자인을 통해서 아동학대 문제를 해결할 가능성을 확인했다는 측면에서 의의가 있다. The aim of this study was to develop the indicators for field survey and evaluation that applied the Crime Prevention Through Environmental Design(CPTED) concept to prevent child abuse in kindergartens. It was found that the eight materials were closely related to this study through the review of legal systems, researches, reports, etc. related to standards for crime prevention and architectural planning in kindergarten. In this study, in order to analyze the appropriateness of the structure of indicators and the importance of individual indicators, Delphi surveys were conducted for 10 experts (6 architecture field, 2 criminology field, and 2 infant education field) who majored in CPTED or had related research experience. The analysis showed that child abuse should be considered mainly in indoor spaces, and that the linkage of the CPTED principles and spatial facility planning elements are important. 45 indicators of three areas (space planning, safety facilities, and education management) were finally derived. In the expert survey(including AHP analysis), the most important indicator was related to surveillance principle by CCTV monitoring, removal of blind spot and concealed space, and the priority for each area was space planning, installation of safety facilities, and education management. These results are consistent with the purpose of this study, which sought to search the cause of child abuse from an environmental perspective. In addition, apart from the CCTV installation proposed as a countermeasure so far, it is meaningful in that it has confirmed the possibility of solving the child abuse problem through environmental design.

학교복합시설 실태조사 현황 분석

강정민(Kang, Jung- Min),강석진(Kang, Seok-Jin),이상민(Lee, Sang-Min) 대한건축학회 2024 대한건축학회 학술발표대회 논문집 Vol.44 No.1

Recently, The problem of school extinction is occurring due to changes in the social structure due to the decrease in the school-age population. Accordingly, the necessity of promoting school complex facilities that can be used by local residents and students has emerged. This study aims to analyze the current status of school complex facilities and derive implications from the perspective of typification. The results of the study are as follows. School complex facilities were distributed around the metropolitan area, but they tended to spread to the region according to policies. In addition, it may vary depending on the location conditions and the needs of local residents, and it means that the school complex can function as an infrastructure. The ownership and operation rights of school complex facilities are determined in consultation with the Office of Education and local governments, but cooperation between institutions is expected to be difficult due to different establishment and operation entities.

근대를 살아간 ‘전통’ 지식인의 교육 활동

강정민 ( Kang Jeong-min ) 청람사학회 2018 靑藍史學 Vol.27 No.-

The reading the diary of the ancient people is the task of looking at the raw personal life and the society reflected in that periods at one time. There were two main characters who kept a diary from 1851 to 1936, the names were Ryu Je-yang and Ryu Hyung-up, they were traditional intellectuals who lived in the transition period of the Modern Society. In this article, we looked at individuals who accepted the turbulent times of modern life through their educational activities. Those were not the men who actively protested the changing times, therefore they have been alienated from official document. But they have been acted by responding to the chaotic times in their own way and tried to integrate the traditional education with the modern things, and those diary by themselves. So, we would like to see the writings, the diary, the process of their exploring and choosing revealed in that diary showed well how traditional and modern things competed, negotiated and created a new social order.

칸트와 스트로슨의 선험성 Transzendental 개념 비교

강정민 ( Jung Min Kang ) 한국칸트학회 2005 칸트연구 Vol.15 No.-

주파수 안정도 향상을 위한 풍력 발전기의 예비력 확보 방법 및 운전 능력 검증

강정민(Jeongmin Kang),박성수(Seongsu Park),심재웅(Jae Woong Shim) 대한전기학회 2023 대한전기학회 학술대회 논문집 Vol.2023 No.7

리눅스 커널 보안 동향

강정민(Jung Min Kang),장인숙(In Sook Jang),남택준(Taek Jun Nam),이진석(Jin Soek Lee) 한국정보보호학회 2005 정보보호학회지 Vol.15 No.2

리눅스가 전자정부 및 다양한 분야에 적용되면서 항상 거론되는 문제점은 보안이다. 더욱이 최근 들어 커널 취약점과 이를 악용한 공격 사례가 발표되면서 응용 수준에서의 보안 노력이 사상누각(砂上樓閣)임을 보여주고 있다. 본 논문에서는 리눅스 커널의 잠재적 혹은 알려진 취약점을 해소하기 위한 커널 수준의 리눅스 보안 요소 기술과 보안 솔루션들을 살펴본다. 또한 본 저자들이 제안하는 모바일 디바이스용 리눅스 보안 커널에 대해 소개한다.

풍동과 예인 수조를 이용한 터빈 성능 비교 시험

강정민(Kang, Jung-Min),이영호(Lee, Yeong-Ho),이규찬(Lee, Kyu-Chan) 한국신재생에너지학회 2011 신재생에너지 Vol.7 No.4

The objective of this paper is to suggest a new method of a wind turbine performance test. The performance test of a wind turbine is generally carried out in a wind tunnel. The test needs not only a high-accuracy measuring system but also durable structure to withstand high speed turbine rotation and wind flow. Therefore, we tried turbine performance test using a towing tank to improve stability and reliability. Because a turbine rotates more slowly and generates more torque in the water than in the wind tunnel under similarity conditions. In this study, we developed turbine performance test systems and verified the turbine test method using a towing tank through comparing results of the wind tunnel and the towing tank test.