• KIISE Transactions on Computing Practices
• /
• v.21 no.3
• /
• pp.257-262
• /
• 2015

As software grows more complex, it contains more bugs that are not recognized by developers. Attackers can then use exploitable bugs to penetrate systems or spread malicious code. As a representative method, attackers manipulated documents or multimedia files in order to make the software engage in unanticipated behavior. Recently, this method has gained frequent use in A.P.T. In this paper, an automatic analysis method to find software security bugs was proposed. This approach aimed at finding security bugs in the software which can arise from input data such as documents or multimedia. Through dynamic taint analysis, how input data propagation to vulnerable code occurred was tracked, and relevant instructions in relation to input data were found. Next, the relevant instructions were translated to a formula and vulnerable input data were found via the formula using an SMT solver. Using this approach, 6 vulnerable codes were found, and data were input to crash applications such as HWP and Gomplayer.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.18 no.4
• /
• pp.171-180
• /
• 2014

Since the execution of structural design by professional structural engineers is not mandatory for small-size buildings in Korea, structural design is conducted by architects or contractors resulting in concern about the seismic safety of the buildings. Therefore, the Korean Structural Engineers Association proposed dedicated structural design criteria in 2012. The criteria were developed based on a deterministic approach in which the structural members are designed only with information of story and span length of the buildings and without structural analyses. However, due to the short time devoted to their development, these criteria miss satisfactory basis and do not deal with structural walls popularly used in Korea. Accordingly, the Ministry of Land, Infrastructure and Transport launched a research on the 'development of structural performance enhancement technologies for small-size buildings against earthquakes and climate changes'.. As part of this research, this paper intends to establish direction for the preparation of deterministic structural design guidelines for seismic safety of domestic small-size reinforced concrete buildings. To that goal, a typical plan of these buildings is selected considering frames only and frames plus walls, and then design is conducted by changing the number of stories and span length. Next, the seismic performance is analyzed by nonlinear static pushover analysis. The results show that the structural design guidelines should be developed by classifying frames only and frames plus walls. The size and reinforcement of structural elements should be provided in the middle level of the current Korean Building Code and criteria for small buildings by considering story and span length for buildings with frames only, and determined by considering the shape and location of walls and the story and span length as well for buildings with frames plus walls. It is recommended that the design of walls should be conducted by reducing the amount of walls along with symmetrically located walls.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.3
• /
• pp.573-583
• /
• 2015

Amcache.hve file is a registry hive file regarding Program Compatibility Assistant, which stores the executed information of applications. With Amcache.hve file, We can know execution path, first executed time as well as deleted time. Since it checks both the first install time and deleted time, Amcache.hve file can be used to draw up the overall timeline of applications when used with the Prefetch files and Iconcache.db files. Amcache.hve file is also an important artifact to record the traces of anti-forensic programs, portable programs and external storage devices. This paper illustrates the features of Amcache.hve file and methods for utilization in digital forensics such as estimation of deleted time of applications.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.9
• /
• pp.2384-2392
• /
• 1999

Software engineers are used to analyse the error behavior of computer programs using test cases which are collected for the testing phase when software errors are detected. In actual software testing and debugging, it is important to adopt dynamic slicing technique which is concerned on all the statements to be affected by the variables of current inputs and to use technique of its implementations. The traditional dynamic slicing has focused on the single slicing criterion algorithm. It has been thought that it is needed to develope and implement algorithm for used multiple criteria variables program slicing, which finds every slicing criterion variable where it is used multiple criteria variables. In this paper, we propose an efficient algorithm to make dynamic program slices when it has used multiple criteria variables. The results of the implementation are presented by the making table on execution history and the dynamic dependence graph. Also we can find that the proposed dynamic program slicing approach using multiple criteria variables is more efficient than the traditional single case algorithm on the practical testing environment.

• The KIPS Transactions:PartC
• /
• v.9C no.2
• /
• pp.149-156
• /
• 2002

Current vaccine program which scans virus code patterns has a difficult to detect the encrypted viruses or polymorphic viruses. The decryption part of polymorphic virus appears to be different every time it replicates. We must monitor the behavior of the decryption code which decrypts the body of the virus in order to detect these kinds of viruses. Specialty, it is not easy for the existing methods to detect the virus if the virus writer has modified the loop count of execution intentionally. In this paper, we propose an advanced emulator using a new algorithm so as to detect various kinds of polymorphic viruses. As a result of experiment using advanced emulator, we found that our proposed method has improved the virus detecting rate about 2%. In addition, our proposed system has a merit that it runs on not only MS-Windows but also Linux, and Unix-like Platform.

• Steel and Composite Structures
• /
• v.25 no.6
• /
• pp.663-670
• /
• 2017

The problem of layup optimization of the composite laminates involves a very complex multidimensional solution space which is usually non-exhaustively explored using different heuristic computational methods such as genetic algorithms (GA). To ensure the convergence to the global optimum of the applied heuristic during the optimization process it is necessary to evaluate a lot of layup configurations. As a consequence the analysis of an individual layup configuration should be fast enough to maintain the convergence time range to an acceptable level. On the other hand the mechanical behavior analysis of composite laminates for any geometry and boundary condition is very convoluted and is performed by computational expensive numerical tools such as finite element analysis (FEA). In this respect some studies propose very fast FEA models used in layup optimization. However, the lower bound of the execution time of FEA models is determined by the global linear system solving which in some complex applications can be unacceptable. Moreover, in some situation it may be highly preferred to decrease the optimization time with the cost of a small reduction in the analysis accuracy. In this paper we explore some machine learning techniques in order to estimate the failure of a layup configuration. The estimated response can be qualitative (the configuration fails or not) or quantitative (the value of the failure factor). The procedure consists of generating a population of random observations (configurations) spread across solution space and evaluating using a FEA model. The machine learning method is then trained using this population and the trained model is then used to estimate failure in the optimization process. The results obtained are very promising as illustrated with an example where the misclassification rate of the qualitative response is smaller than 2%.

• Journal of the Korean Society of Safety
• /
• v.36 no.1
• /
• pp.44-49
• /
• 2021

Domestic industrial accidents continue to increase, with 2,142 deaths in 2018, up by 185 (9.5%) from 1,957 deaths in 2017. Industrial accidents that cause loss of human lives pose a serious risk to businesses because of the strengthening of safety regulations and the changing public perception of social responsibility. Accordingly, to prevent industrial accidents, companies regularly conduct onsite safety activities and conduct education and training to raise awareness among employees. However, many such corporate activities are not conducted voluntarily and practically by employees but mostly by formal implementation. To discontinue this customary and passive behavior of employees and establish a mature safety culture, strengthening the execution power of safety management at the site is of paramount importance, and to this end, we aim to utilize the safety practice index (SPI). In this study, the SPI calculated on the basis of the results of the 2018 and 2019 risk management and safety activities of a site was compared with the reported safety accidents. The results confirmed that the SPI index can be used as a valid indicator for safety activities for accident prevention, such as strengthening leadership and safety policies to grade and manage safety management levels for a certain period of time or by a department or to convert weaknesses into strengths.

• Journal of the Korean Society of Systems Engineering
• /
• v.18 no.2
• /
• pp.58-74
• /
• 2022

Deterministic accident analysis plays a central role in the nuclear power plant (NPP) safety evaluation and licensing process. Traditionally the conservative approach opted for the point kinetics model, expressing the reactor core parameters in the form of reactivity and power tables. However, with the current advances in computational power, high fidelity multi-physics simulations using real-time code coupling, can provide more detailed core behavior and hence more realistic plant's response. This is particularly relevant for transients where the core is undergoing reactivity anomalies and uneven power distributions with strong feedback mechanisms, such as reactivity initiated accidents (RIAs). This work addresses a RIA, specifically a control element assembly (CEA) withdrawal at power, using the multi-physics analysis tool RELAP5/MOD 3.4/3DKIN. The thermal-hydraulics (TH) code, RELAP5, is internally coupled with the nodal kinetics (NK) code, 3DKIN, and both codes exchange relevant data to model the nuclear power plant (NPP) response as the CEA is withdrawn from the core. The coupled model is more representative of the complex interactions between the thermal-hydraulics and neutronics; therefore the results obtained using a multi-physics simulation provide a larger safety margin and hence more operational flexibility compared to those of the point kinetics model reported in the safety analysis report for APR1400. The systems engineering approach is used to guide the development of the work ensuring a systematic and more efficient execution.

• Journal of Korean Dental Hygiene Science
• /
• v.5 no.1
• /
• pp.21-27
• /
• 2022

Background: This study was conducted to analyze the time for re-detection of bacteria after surface disinfection using wet wipes, isopropyl alcohol, and benzalkonium chloride antibacterial tissue and provide standards for re-execution of surface disinfection with wet and antibacterial tissues. Methods: Seven laptops were wiped with wet tissue and isopropyl alcohol and benzalkonium chloride antibacterial tissues. Test areas were rubbed with a sterile cotton swab at baseline and after 30, 60, and 120 min. After plating on a tryptic soy agar medium, the number of colonies was counted by culturing at 36.5℃ for 24 h. Results: The average number of bacterial colonies was 5.85 ± 4.33 before isopropyl alcohol wiping and nil after wiping. The average number of bacterial colonies was 12.28 ± 14.67 benzalkonium chloride wiping and nil after wiping. Before wiping with wet wipes, the average number of bacterial colonies on laptop surfaces was 3.42 ± 5.22. Bacteria decreased after wiping with wet wipes but increased again over time. Conclusions: Wet wipes can temporarily reduce bacteria but are unsuitable for removing bacteria.

• International Journal of Computer Science & Network Security
• /
• v.22 no.1
• /
• pp.241-247
• /
• 2022

This study examines teachers' implementation of strategies to modify the aggressive behavior of students with intellectual disabilities in Saudi Arabia, to determine the obstacles to their real-world execution. In addition, it presents potential approaches to overcome the obstacles to implementing strategies with this group of students. The research employed a qualitative design using semi-structured interviews as a data collection tool and applied a thematic analysis. The study population comprised 35 teachers of students with intellectual disabilities and the study sample numbered six teachers. The interviews were conducted via different methods: three by phone, two face-to face, and one using the Zoom platform. The results revealed inadequate understanding among teachers of intellectual disability and behaviour modification strategies, and this affected their capacity to develop plans that were compatible with the needs of students with intellectual disability. The findings also identified multiple obstacles that impede teachers' implementation of strategies to modify aggressive behaviour among students with intellectual disabilities; the most important being the lack of input from a psychological specialist when developing programs to modify aggressive behaviour. In general, it is apparent that programs for modifying aggressive behaviour are neither structured nor complementary, due to the scarcity of administrators with sufficient knowledge and familiarity with the characteristics and personalities of students with intellectual disabilities. This study presents several recommendations, the most important of which is that teachers of students with intellectual disability should develop themselves through training courses to enable them to deal with these students and create treatment plans that include strategies and clear steps to modify the aggressive behaviour of students with intellectual disabilities. To support teachers, it is also necessary to remove the obstacles facing education centres by providing financial support to create an environment in which they can access the required devices and equipment in their classes.