BinTyper : type confusion detection for C++ Binaries

김동주 Graduate School of Cybersecurity, Korea University 2021 국내석사

타입 컨퓨전 버그는 C++로 개발된 소프트웨어를 공격하기 위해 사용되는 인기 있는 취약점 클래스 중 하나이다. 이 버그는 프로그램이 오브젝트를 호환되지 않는 클래스 타입으로 형변환(타입캐스팅)하여 발생한다. 공격자는 이 취약점(버그)을 악용해 대상 소프트웨어에서 악성 코드를 실행할 수 있다. 유형 혼동 버그를 탐지하기 위한 기존 연구들은 모두 소스 코드 수준에서 제안되었다. 이들은 소스 코드의 컴파일 과정에서 타입캐스팅 연산자에 타입 호환성을 검증하기 위한 추가적인 코드를 삽입하여 런타임에서 타입 컨퓨전 버그를 탐지한다. 그러나 이러한 방법들은 바이너리 수준에서 적용될 수 없다. 컴파일된 바이너리에는 클래스 정보와 타입캐스팅 연산자 등의 고수준 정보가 존재하지 않기 때문이다. 본 논문은 바이너리 수준에서 타입 컨퓨전 버그를 탐지할 수 있는 최초의 도구인 BinTyper를 제안한다. BinTyper는 정적 분석을 통해 클래스 오브젝트를 클래스 상속 구조에 따라 여러 영역으로 나눈다. 이후 동적 분석을 수행해 타입 컨퓨전 버그를 유발하지 않고 프로그램이 실행되기 위해 오브젝트에 필요한 조건들을 추론한다. 마지막으로, 추론된 조건들을 바탕으로 타입 호환성을 검증하여 타입 컨퓨전 버그를 탐지한다. 우리는 제안된 방법을 Google PDFium과 LibSass에 적용해 바이너리 수준에서 타입 컨퓨전 버그를 성공적으로 탐지하였다. Type confusion bug is a popular vulnerability class used to attack C++-based software. This bug occurs when a program typecasts an object to an incompatible class type. An attacker can exploit this vulnerability to execute malicious code on the target software. Existing researches to detect type confusion bugs have been proposed at the source level. They perform detection at runtime by adding extra code that verifies type compatibility to the typecasting operator. However, this approach is not applicable at the binary level, because high-level information such as class information and the typecasting operator does not exist in the compiled binary. In this paper, we propose BinTyper, a tool that detects type confusion bugs at the binary level for the first time. BinTyper divides the object into several areas according to the class hierarchy by static analysis. After that, BinTyper performs dynamic analysis to infer the condition of the object for the program to be executed without causing a type confusion bug. Finally, based on the inferred condition, type compatibility is verified to detect a type confusion bug. We actually applied our proposed method to Google PDFium and LibSass, which confirmed that our proposed method successfully detects a type confusion bug at the binary level.

전북지역 산업체 급식소 조리종사자의 고용형태에 따른 안전사고 실태 및 안전사고 예방수칙에 대한 중요도와 실천도 분석

소희 전북대학교 교육대학원 2017 국내석사

Research Objective: The purpose of this study was to investigate the status of safety accidents, the status of safety education, the level of safety knowledge, and the degree of importance and performance of precautions of safety accidents according to the type of employment for workers in industrial food service in Jeonbuk area. Research Methods: The 282 regular and non-regular workers in industrial food service in Jeonbuk area were used in the final analysis. The questionnaires were comprised general characteristics, safety accident status of food service room, safety education state, safety knowledge evaluation, importance and performance about precautions of safety accidents. Statistical data analysis was being completed using SPSS v.20.0. Research Results: 96.5% of cook workers are women, men are 5 regular workers and 5 non-regular workers. The final education level of the cooking staff was the highest with 69.5% graduated from high school. 65.5% of regular workers and 72.4% of non-regular workers were the highest in high school graduation . Above university graduation that 8.4% for regular workers and 1.8% for non-regular workers were the lowest and there was a significant difference(p<0.05). In the case of annual salary, the regular worker was the highest with more than 15 million won (68.1%), while the non-regular workers was the highest with more than 10 to 15 million won(47.9%)(p<0.001). The highest level of cooking staff was cook assistant(78.4%). Regular workers were 75.6% of cook assistant and 24.4% of cooks, while the non-regular workers were 80.4% for cook assistant, 11.7% for cooks and 8.0% for part-time workers and there was a significant difference between the regular and non-regular workers(p<0.001). In the case of the number of meals per day of regular workers, 2 diet was the highest of 38.7% and 4 diet was the lowest with 16.8%. In the case of non-regular workers, 3 diet was the highest with 33.7% and 4 diet was the lowest with 4.3%(p<0.001). The average age of cooked workers was 50.48 years old, the regular workers were 48.68 years old and the non-regular workers were 51.79 years old(p<0.001). 58.9% of cook workers experienced food safety accidents and 66.4% of regular workers and 53.4% of non-regular workers experienced safety accidents(p<0.05). 98.3% of the regular workers and 95.1% of the non-regular workers were conducted in the safety education for the cooking staff. 29.9% of the regular workers and 33.5% of the non-regular workers were evaluated education as training tests(p<0.05). The average score of safety knowledge of cooking staff was 0.76 out of 1, and the correct answer rate was 76.4%. Among the items higher than the average rating, ‘When smelling gas leaking, blocking valve and unplug various electric cords’ was the highest with 0.95 and ‘For expired of unused chemicals, let it flow to drainage after mixing chemical substances with water’ was the lowest with 0.80. As a result of comparative analysis of the importance of safety accident prevention policies by type of employment, the average value was 4.26 points for regular workers and 4.15 points for non-regular workers. In regular workers, ‘Do not let water in the case of frying oil, pay attention to the burning’ had the highest score of 4.43 and ‘When handling heavy materials must keep the right attitude and method’ had the lowest score of 4.27. In non-regular workers, ‘If floor is slippery while working, remove oil element immediately by using detergent’ was the highest with 4.29 points and ‘Keep the knife at hidden place or do not leave it in sink and other places with water’ was the lowest with 4.17 point. Among the 21 items, ‘Do not let water in the case of frying oil, pay attention to the burning’ showed significant difference(p<0.05). As a result of comparative analysis of the degree of performance about precautions of safety accident, the average value was 3.95 points for regular workers and 3.94 points for non-regular workers. ‘The tidy the product, materials in the workplace and passage’ had the highest score of 4.14, and ‘When putting food in vegetable cutter or ingredient grinder, use exclusive stick’ had the lowest score of 3.97. ‘If floor is slippery while working, remove oil element immediately by using detergent’ had the highest score of 4.09, and ‘When handling heavy materials must keep the right attitude and method’ had the lowest score of 3.96. There was no significant difference between the regular and non-regular workers. Analysis of Importance and performance about precautions of safety accidents were significant difference(p<0.001). The average score is 4.26 points of importance and 3.95 points of performance. The score of importance was higher. There was a significant difference between the importance and performance of non-regular workers in the precautions of safety accidents(p<0.001). The mean score was 4.15 for criticality and 3.94 for performance. Safety knowledge was significantly correlation with importance and performance about precaution of safety accidents. Importance of precaution of safety accidents was significantly correlation with performance about precaution of safety accidents. Conclusion: The study showed that the status of safety accidents was influenced by employment type, safety knowledge, importance level about precautions of safety accident, performance about precautions of safety accident are have a correlation. In order to prevent safety accidents, it is necessary to improve consciousness of the foodservice manager, for effective application of safety education contents, development of contents, media of education is needed. In addition, the sense of discrimination the division of employment type should be lowered to promote responsibility and safety awareness. In order to raise the importance and performance about precautions of safety accident, it is necessary to prepare diverse ways to stabilize the employment of cook workers.

유동-구조 연성해석을 이용한 파일럿타입 안전밸브의 구조안정성 평가

김태관 동아대학교 대학원 2018 국내석사

한국 소비자의 수입식품 안전성 인식에 관한 연구

우인인 경희대학교 일반대학원 2015 국내석사

This study was designed to be crucial in enhancing Korea consumers’ safety perception and helping them lead a safe dietary life. After the import liberalization, our domestic market has ben opened and imported gods from a lot of countries, and consumers have ben using them for their consuming life in diverse ways. In particular, as imported fod’s table ocupation has ben constantly increasing, it wil be meaningful to figure out safety perception and purchase Intention regarding it. On national image and imported fod intake consists of familar experience apreciate the safety awarenes This increases the degre of buying a safe diet can be a problem because it is recognized corectly, the safety of imported fod products under the corect judgment information to be made available for purchase, and consumer education wil be made. The number of imported fod into Korea year by year. This study aims to find out the influence factors of imported fod safety awarenes which wil afect the purchase intention on the basis of SERVQUAL model. This study involves a survey conducted from Oct. 2 to Nov. 12, 2014. Total 38 questionaires were colected and analyzed. Mean, standard deviation, frequency analysis, exploratory factor analysis, corelation, multiple regresion, path analysis were analyzed, using SPS 21.0 program and AMOS 21.0 program.

전북지역 학교 유형에 따른 학교급식 조리종사자의 안전사고 실태 및 안전사고 예방관리에 대한 중요도와 수행도 분석

이향진 전북대학교 교육대학원 2020 국내석사

Research Objective : The purpose of the study was to evaluate status of safety accidents, work intensity and cooking environment, status of safety education, level of safety knowledge, importance-performance analysis (IPA) about precautions of safety accidents by school type of school foodservice employees in Jeonbuk area. Research Methods : The questionnaire of 316 school foodservice employees in Jeonbuk area was used for the final analysis. The questionnaire consisted of characteristics, status of safety accidents, work intensity and cooking environment, status of safety education, assessment of safety knowledge, importance and performance about precautions of safety accidents. Statistical data were analyzed using SPSS 25.0. Research Results : Cooking workers who have experienced safety accidents in the last two years were found to be 89.2% in elementary schools and 93.4% in middle and high schools. Among the types of safety accidents, ‘Musculoskeletal diseases(68.2%)’ was found to be the highest incidence in elementary schools, and so were ‘slip, fall(70.2%)’ and ‘burn(70.2%)’ in middle and high schools. The recognition level for the work intensity and cooking environment averaged 4.12 ± 0.60 and 2.78 ± 0.74 (based on 5 points). There were no significant differences depending on the type of school. In both groups, the question ‘I have an ache on a specific spot of my body due to repetitive work’ had the highest level of awareness of the intensity of work. In both groups, the question ‘The temperature and humidity of the cooking room are suitable for working’ had the lowest level of awareness of the cooking environment. Cooking workers received 100% safety education from dietitian(nutrition teacher) and education offices for 1 year. However, 29.9% of elementary schools and 23.0% of middle and high schools received safety education from Korea Chefs Association. In both groups, the biggest reason for dissatisfaction with safety education was ‘Content is not suitable for actual site’ and the biggest reason for not applying safety education contents to work was ‘Heavy workload & lack of time’. The results of the safety knowledge level evaluation of cooking workers, it was 0.91 ± 0.08 for elementary schools and 0.90 ± 0.11 for middle and high schools (based on 1 point). Independent sample t-test analysis results, showed that the importance of safety accident precautions was significantly higher in middle and high schools than elementary schools, depending on the types of schools (p<0.05). There was no significant difference in the performance of safety accident precautions depending on the types of schools. Paired samples t-test analysis results, both groups showed significantly higher importance between importance and performance of safety accident precautions(p<0.001). As a result of the IPA analysis, for elementary schools, areas A, B and C included 15 items of safety management status(slip/burn risk, cut/stenosis risk, collision/downfall risk, electric shock/fire risk). Area D included 6 items of health care status(musculoskeletal diseases prevention, chemical substance management) and 1 item of safety management status. For middle and high schools, areas A, B and C included 15 items of safety management status and 1 item of health care status. Area D included 5 items of health care status and 1 item of safety management status. A low correlation was shown between cooking environment and performance of safety accident precautions(r=0.239, p<0.01). Positive correlation was shown between importance and performance of safety accident precautions(r=0.342, p<0.01). Conclusion : Therefore, in order to improve the performance of safety accident precautions, it is necessary to improve the cooking environment and raise awareness of importance. In particular, the area of musculoskeletal diseases prevention and chemical substance management needs professional and continuous education to recognize and practice its importance. In addition, proper placement of cooking workers is important and elementary schools need to supplement cooking workers in consideration of school conditions.

고령자의 무동력 승강식 피난기 사용 시 인체 영향 평가

강영석 전북대학교 일반대학원 2022 국내석사

In modern society, buildings are becoming high-rise due to the phenomenon of population density caused by urbanization. With the increase in these high-rise buildings, the risk of disasters is increasing. High-rise buildings, unlike general buildings, can cause massive casualties in the event of a fire. In order to prevent casualties in disaster situations, the evacuation capacity of the occupants must be guaranteed, and it is necessary to develop design standards for securing evacuation safety or evacuation facilities and evacuation equipment capable of self-evacuation. The evacuation elevator used in this study has been developed by Didimdol Co., Ltd., a company specializing in manufacturing fire evacuation facilities, to solve the problems of the previously proposed evacuation facilities. Introduced by the 2011 National Fire Safety Standards (NFSC 301), the lift evacuation device can be installed by connecting to the inner balcony, outer wall, and balcony of the apartment, and is a fire evacuation device that descends by gravity without power. In the case of existing evacuation mechanism-related studies, improvement of the firefighting method was proposed through evaluation of performance, design, and evacuation time, or a solution was proposed in consideration of field adaptability. Evacuation elevators have been developed in consideration of the safety of the homeless, such as the elderly and the disabled, as well as adaptability in high-rise buildings, but studies on human impact through bio-signal analysis are insufficient. In particular, in the case of elevator evacuation, it is a new evacuation tool and vertically evacuates without power in consideration of user safety, and it is designed to be easy to use by anyone in a one-touch method, but research on quantitative evaluation using bio-signals is insufficient. Concerns about additional accidents due to the use elevator evacuation can be caused by injuries due to posture imbalance or failure to use the instrument due to mental stress caused by emergencies. Myoelectricity is a method of measuring the microscopic activity potential that occurs in the muscle and nervous system when the muscle contracts. It can diagnose muscle diseases or assess body load. Postural balance can be evaluated based on gravity through foot pressure analysis along with electromyography. Heart rate changes through exercise, but as a tool to detect emergency situations under physical and mental stress in real time, it can be an indicator of the mental load of emergency situations that affect evacuation behavior. Therefore, in this study, user satisfaction survey was conducted using a Elevator-type Evacuation, and the effect on evacuation behavior was analyzed through repeated evacuation training and quantitative analysis of bio-signals such as electromyography, foot pressure, and heart rate according to safety handle height. Heart rate was analyzed for before and after comparison of psychological factors, and EMG and left and right foot pressures of major muscles in the lower extremities were analyzed for evaluation of physical factors affected by repeated use.

인장형 에너지흡수부재를 이용한 철도차량용 장애물제거기 연구

김홍익 과학기술연합대학원대학교 2017 국내석사

장애물제거기는 선로 내 장애물에 의한 충돌사고 발생 시 장애물을 선로 밖으로 밀어내거나 소성변형을 통해 충돌에너지를 흡수하여 열차의 탈선을 막는다. 장애물제거기는 사고 발생 이후 피해를 최소화하기 위한 장치이기 때문에 장애물과의 충돌에 의한 감속도의 변화가 최소화된 안정적인 하중특성이 요구된다. 본 논문은 인장형 에너지흡수부재와 4절 링크를 사용하여 안정적이면서도 예측이 용이한 하중특성을 가진 장애물제거기를 설계하고 정적강도 및 에너지흡수성능 검증시험을 통해 관련 규정을 만족하는 성능을 가진 장애물제거기를 설계하는데 목적이 있다. 장애물제거기의 작동 메커니즘을 구현하기 위해 4절 링크 및 인장형 에너지흡수부재가 조합된 링크의 기하학적 해석을 수행하여 각 구조물의 위치를 결정한 뒤 장애물제거기를 설계하였다. 이후 유한요소해석을 통해 장치의 성능을 확인한 뒤, UTM(Universal Test Machine)을 이용한 성능 시험법을 고안하였다. 이를 이용하여 EN15227 규정에 따라 UTM을 이용한 정적강도 및 에너지흡수성능 검증시험을 수행하여 장애물제거기의 성능 검증을 완료하였다. 본 연구를 통해 인장형 에너지흡수부재 및 4절 링크로 구성된 작동 메커니즘을 구성하여 안정적이고 예측 가능한 하중특성을 구현하였다. 특히 변형에 따라 추종힘의 방향이 달라지는 것을 고려한 슬라이딩 지그를 고안하여 적용하였으며, 시험 결과 유한요소해석과 유사한 형태의 거동을 보였다. 제안된 장애물제거기의 설계 및 검증 절차에 따라 붕괴하중을 쉽게 조절이 가능하며 실험적으로 검증할 수 있는 방법을 제안하였다.

Structural safety and serviceability evaluation for the new connection system of hybrid truss bridges

정광회 Graduate School, Yonsei University 2012 국내박사

회전익 항공기 비행 시뮬레이터를 통한 비행착각 감지 Tool 개발에 관한 연구

임세훈 한국항공대학교 일반대학원 2024 국내박사

Despite the systematic advancements in aviation industry technology and safety management, accidents of spatial disorientation in helicopter persistently occur. Spatial disorientation, a phenomenon where the pilot perceives the aircraft's attitude differently from its actual orientation, arises from multifaceted causes including fatigue, stress, and low-visibility conditions. Research dedicated to detecting flight illusions has predominantly centered on human factors like pilots' physiological attributes and behavioral responses. However, the development of a commercialized tool for detecting spatial disorientation remains unrealized. Predominantly, spatial disorientation fall under Type I category, characterized by the pilot's lack of awareness, thereby imposing constraints on the effectiveness of detecting these illusions solely based on physiological responses of pilots. Consequently, this study endeavors to develop an innovative tool for the detection and response to spatial disorientation in helicopter. The methodology of this research involved designing scenarios that closely mirror actual flight conditions, thereby facilitating the collection of high-quality data. Subsequently, the reliability of this data was ascertained through meticulous error rate analysis. The gathered data underwent a rigorous process of feature selection criteria establishment and the formulation of data labeling algorithms, enhancing the precision of spatial disorientation classification and detection accuracy. This study yielded significant findings, confirming that flight data encompassing control device input values, aircraft attitude values, and specification values serve as reliable standards for the precise detection of spatial disorientation scenarios. Moreover, it established that beyond the traditionally recognized factors of pitch and bank associated with spatial disorientation, parameters such as heading, pedal, collective, and aircraft velocity emerge as pivotal in detecting spatial disorientation. Furthermore, the study employed error rate analysis and phenomenological research to substantiate that factors like a pilot's qualification level and possession of Instrument Flight Rules (IFR) qualification play a crucial role in the incidence of errors related to spatial disorientation. The research highlighted a prevalent state of psychological anxiety among helicopter pilots, attributable to complex mission environments and inadequate training. When this state is compounded with human factors such as nocturnal and moonless conditions, fatigue, and stress, the propensity for spatial disorientation escalates significantly. The application of this tool, as proposed by the study, has the potential to enhance the accuracy in recognizing spatial disorientation conditions. Effectively responding to these conditions through improvements in pilot education and training could significantly contribute to the mitigation of helicopter accidents.

수의 중재적 시술을 위한 커튼 타입 방사선 방호 장치의 평가

최민식 충북대학교 일반대학원 2024 국내석사