• Title/Summary/Keyword: Security Techniques

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A Review of Change Detection Techniques using Multi-temporal Synthetic Aperture Radar Images (다중시기 위성 레이더 영상을 활용한 변화탐지 기술 리뷰)

  • Baek, Won-Kyung;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.35 no.5_1
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    • pp.737-750
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    • 2019
  • Information of target changes in inaccessible areas is very important in terms of national security. Fast and accurate change detection of targets is very important to respond quickly. Spaceborne synthetic aperture radar can acquire images with high accuracy regardless of weather conditions and solar altitude. With the recent increase in the number of SAR satellites, it is possible to acquire images with less than one day temporal resolution for the same area. This advantage greatly increases the availability of change detection for inaccessible areas. Commonly available information in satellite SAR is amplitude and phase information, and change detection techniques have been developed based on each technology. Those are amplitude Change Detection (ACD), Coherence Change Detection (CCD). Each algorithm differs in the preprocessing process for accurate automatic classification technique according to the difference of information characteristics and the final detection result of each algorithm. Therefore, by analyzing the academic research trends for ACD and CCD, each technologies can be complemented. The goal of this paper is identifying current issues of SAR change detection techniques by collecting research papers. This study would help to find the prerequisites for SAR change detection and use it to conduct periodic detection research on inaccessible areas.

A Comparative Study of the Security Prevention Strategies on Arson: Focused on the Behavioral Characteristics between Serial Arsonists and Simple Arsonists (방화범죄의 경비예방 전략에 관한 비교연구 - 연쇄방화범과 단순방화범의 행위적 특성을 중심으로 -)

  • You, Wan-Seok;Hwang, Sung-Hyun
    • Korean Security Journal
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    • no.29
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    • pp.139-162
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    • 2011
  • The purpose of this study is to compare with the general and behavioral characteristics between simple and serial arsonists using the data derived from Scientific Crime Analysis System, Criminal Filing Search System, and Crime Information Management System. The analysis and findings reported here are derived from data extracted from 160 arsonists arrested by police officer. The independent variables included such socio-economic characteristic as arsonists' gender, age, occupation, education level, and previous criminal records of arsonists, and finally the general characteristics of the scene of fire settings. The dependent variable is whether or not serial fire setter. To achieve the purpose, the analysis of frequencies and cross-tab were conducted. According to frequence and cross-tab analysis, there are great differences of the general and behavior characteristics between two groups. In the comparison of simple and serial arsonists, serial arsonists are more likely to have previous criminal records, low socio-economic status, unmarried and no cohabitants than simple arsonists. furthermore, serial arsonists are more likely to use garbage papers for fire setting in the scene of the crime, to have mental or psychological problems, and to get involved in fire setting for the psychological pleasure than simple arsonists do. The present research has some obvious limitations. First, the analysis is based only on arsonists arrested by police officers. These may be considerable differences in arsonists arrested by police officers and fire setters not arrested by them. Additional research is needed to assess the extent to which these findings would apply to fire setters not arrested by police officer in Korea. Secondly, the data in this study are cross-sectional and simple cross-tab analysis are used. Potential limitation of cross-sectional data concerns the inability to specify the changes in measures as arsonists behavioral characteristics. Therefore, further studies need to use longitudinal data and more complicate statistical techniques such as correlation analysis, multiple regression analysis, or LISREL models to specify the casual relationships between dependent and independent variables for fire settings. Even if this study has some limitations, it is meaningful in which it first investigated the comparison of simple and serial arsonists focusing on the general and behavioral characteristics between two groups in Korea.

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A Static Analysis Technique for Android Apps Written with Xamarin (자마린으로 개발된 안드로이드 앱의 정적 분석 연구)

  • Lim, Kyeong-hwan;Kim, Gyu-sik;Shim, Jae-woo;Cho, Seong-je
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.3
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    • pp.643-653
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    • 2018
  • Xamarin is a representative cross-platform development framework that allows developers to write mobile apps in C# for multiple mobile platforms, such as Android, iOS, or Windows Phone. Using Xamarin, mobile app developers can reuse existing C# code and share significant code across multiple platforms, reducing development time and maintenance costs. Meanwhile, malware authors can also use Xamarin to spread malicious apps on more platforms, minimizing the time and cost of malicious app creation. In order to cope with this problem, it is necessary to analyze and detect malware written with Xamarin. However, little studies have been conducted on static analysis methods of the apps written in Xamarin. In this paper, we examine the structure of Android apps written with Xamarin and propose a static analysis technique for the apps. We also demonstrate how to statically reverse-engineer apps that have been transformed using code obfuscation. Because the Android apps written with Xamarin consists of Java bytecode, C# based DLL libraries, and C/C++ based native libraries, we have studied static reverse engineering techniques for these different types of code.

A Remote User Authentication Scheme Preserving Anonymity and Traceability with Non-Tamper Resistant Smart Cards (정보추출 가능한 스마트카드 환경에서 익명성과 추적성을 제공하는 원격 사용자 인증 기법)

  • Kwon, Hyuck-Jin;Ryu, Eun-Kyung;Lee, Sung-Woon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.159-166
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    • 2013
  • Recently, because the interest and needs in privacy protection are growing, smartcard-based remote user authentication schemes have been actively studied to provide the user anonymity. In 2008, Kim et al. first proposed an authentication scheme in order to ensure the user anonymity against both external attackers and the remote server and track malicious users with the help of a trusted trace sever. However, in 2010, Lee et al. showed that Kim et al.'s scheme cannot provide the user anonymity against remote server, which is because the server can trace users without any help of the trace server, and then proposed a improved scheme. On the other hand, in 2010, Horng et al. proposed an authentication scheme with non-tamper resistant smart cards, in which the non-tamper resistant smart card means that an attacker may find out secret information stored in the smart card through special data analysis techniques such as monitoring power consumption, to be secure against a variety of attacks and to provide the user anonymity against external attackers. In this paper, we will propose a remote user authentication scheme with non-tamper resistant smart cards not only to ensure the user anonymity against both external attackers and the remote server but also to track malicious users with only the help of a trusted trace sever.

Police knighthood introduction and training the realities -Taekwondo's introduction- (경찰 무도의 교육훈련 실태조사 - 태권도 교육 중심으로 -)

  • Oh, Jeong-Soo
    • Korean Security Journal
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    • no.13
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    • pp.259-277
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    • 2007
  • The results of realities of the Taekwondo training in Korea National Police University, Police Comprehensive Academy, National Central Police Academy, and police stations and of realities of the Taekwondo blackbelt holders are as below. 1. The Taekwondo training time of Korea National Police University is 4 hours per week for freshmen and 2 hours per week for sophomores, juniors, and seniors. 2. The Taekwondo training of Police Comprehensive Academy is basis for police lieutenants and sergeants. time for Taekwondo training is not allotted in the education course but only allotted as a liberal everyday exercise. In the chivalry master course, 71% of the course composes of basic policeman and on-site arrest techniques and pliceman chilvary such as Taekwondo, and judo. The cadets must select one item among the policeman chivalry and take Taekwondo training for 150 hours during 52 weeks acquire the first grade to be appointed as lieutenant simultaneously with the graduation. 3. The Taekwondo training for newly appointed policemen of National Central Police Academy is 104 hours of arresting criminals and self-protection. 4. In the Taekwondo training in the police stations, when a master completes more than two times of training per month, he receives the first grade by examination and be promoted by one grade each. 5. The policemen with Taekwondo black belt are more than 2.6 times of judo, 4.6 times of fencing, 5.9 times of hapgido.

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Lightweight Authentication Scheme for Secure Data Transmission in Terrestrial CNPC Links (지상 CNPC 링크에서 안전한 데이터 전송을 위한 경량화된 인증기법)

  • Kim, Man Sik;Jun, Moon-Seog;Kang, Jung Ho
    • KIPS Transactions on Software and Data Engineering
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    • v.6 no.9
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    • pp.429-436
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    • 2017
  • Unmanned Aerial Vehicles (UAV) that are piloted without human pilots can be commanded remotely via frequencies or perform pre-inputted missions. UAVs have been mainly used for military purposes, but due to the development of ICT technology, they are now widely used in the private sector. Teal Group's 2014 World UAV Forecast predicts that the UAV market will grow by 10% annually over the next decade, reaching $ 12.5 billion by 2023. However, because UAVs are primarily remotely controlled, if a malicious user accesses a remotely controlled UAV, it could seriously infringe privacy and cause financial loss or even loss of life. To solve this problem, a secure channel must be established through mutual authentication between the UAV and the control center. However, existing security techniques require a lot of computing resources and power, and because communication distances, infrastructure, and data flow are different from UAV networks, it is unsuitable for application in UAV environments. To resolve this problem, the study presents a lightweight UAV authentication method based on Physical Unclonable Functions (PUFs) that requires less computing resources in the ground Control and Non-Payload Communication (CNPC) environment, where recently, technology standardization is actively under progress.

An Empirical Study on the Relationship Between Firm Characteristics, Financial Security Indices, and Financial Profit Indices of Korean Private Venture Capital Firms (창업투자회사의 특성과 재무안정성 및 수익성지표 간의 관계에 대한 실증적 연구)

  • Lee, Joo-Heon;Kim, Sung-Min
    • Korean Business Review
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    • v.19 no.1
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    • pp.157-174
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    • 2006
  • In the past, because Korean private venture capital firms could get government support and subsidies, they could be survived in the market without having required management capabilities, advanced venture investment techniques, and professional supporting agencies and institutions. However, business environments have changed a lot recently. Now, only through identifying the optimal financial structures(the ratio of debt to equity), Korean private venture capital firms can minimize investment risks and ensure higher profits. Since Modigliani and Miller(1958) criticized the existence of the optimal financial structure, there have been numerous studies on the optimal financial structure of firms. However, there is no empirical study investigating the financial structure of venture capital firms. The purpose of this article is to analyze the relationship between firm characteristics, financial security indies, and financial profit indices of korean private venture capital firms. We gathered the data from various sources, including the web pages and the financial statements for 2003 and 2004. By using the student's t-test and the correlation analysis, we showed that there are differences in the current ratio and the ratio of net profit to net sales between new and old korean private venture capital firms. Even though it is known that korean private venture capital firms does not have enough knowledge and investment technique to compete with global venture capital firms, our result show that old korean private venture capital firms have already built some knowledge and understanding of venture capital investing.

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Study on Preventing Retaliation against Crime Victims (범죄피해자에 대한 보복범죄 방지 대책에 관한 연구)

  • Choi, KeeNam
    • Convergence Security Journal
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    • v.16 no.7
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    • pp.129-137
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    • 2016
  • The guarantee of citizens' safety from crime is the reason for a nation's existence according to the social contract, and it is also a salient task in securing the citizens' right to the pursuit of happiness, which is a constitutional right expressing the nation's duty to its citizens. First, a procedure must be made mandatory that corresponds to the Miranda rule applied during the arrest of criminal suspect, which verifies whether there exists a risk of retaliatory crime to the victim of crime, crime reporter, or witness following their report of a crime or testimony. A measure to punish those who violate this should be devised. The second is the improvement of related laws and systems, such as expanding the scope of persons subject to protection from retaliatory crimes under the current law and strengthening information protection. Third, a retaliatory crime risk evaluation index must be developed, and the evaluation results must be quantified to clearly state measures and responsibilities, in detail, for personal safety at each level of intensity. The fourth is the expanded implementation of proactive personal safety measures for victims of crime and witnesses, as well as the development and application of advanced techniques. The last is a change in the perception s of those working for the judicial body. From the initial investigation stage of the crime to the diagnosis regarding the possibility of retaliation perpetrated on an ex-convict through psychological tests, systems of general cooperation, and mutual assistance must be established.

A Study on Community Counter-terrorism (지역사회 대테러활동에 관한 연구)

  • Jung, Woo-Il
    • Korean Security Journal
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    • no.19
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    • pp.187-205
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    • 2009
  • In this study, Horgan(2005)'s argument highlights the centrality to any successful counter-terrorism strategy of understanding the social context in which terrorist ideologies take root. Counter-terrorism refers to the practices, tactics, techniques, and strategies that governments, militaries, police departments and corporations adopt in response to terrorist threats and/or acts, both real and imputed. Pickering et al.(2008) historically explained four counter-terrorism strategies as traditional counter-terrorism model, community intelligence model, belonging model, social cohesion model. It is thus proposed that counter-terrorism strategies are based in established networks within the community and proactively seeks to continually renew these relationships between the community and police. This approach must embrace an explicit recognition of multiculturalism and its political imperative and drive in a policing organization explicitly committed to social cohesion and human rights in both discourse and practice. We, therefore, suggests community tree counter-terrorism approaches, or community intelligence model, belonging model and social cohesion model to apply to counter-terrorism agencies in Korea. These models are on the basis of Pickering et al.'s counter-terrorism models, which by using community policing to boot socially cohesion police are better able to position themselves as mediators to negotiate settlements between the competing demands of different social groups.

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The Process Control Using Modeling Technique in A2O Sewage Treatment Process (모델링기법을 이용한 A2O 하수처리공정에서 주요 공정관리에 관한 연구)

  • Park, Jung Soo;Kim, Sung Duk;Seung, Dho Hyon
    • Journal of Korean Society of Disaster and Security
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    • v.13 no.2
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    • pp.65-75
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    • 2020
  • The efficiency of sewage treatment was ananlyzed selecting a sewage treatment plant in Gyeonggi-do where A2O process was applied. Statistical techniques based on the operation data of the sewage treatment were used. The main factors directly affecting the efficiency of the treatment process were analyzed using a GPS-X model. The correlation analysis and one-way ANOVA were performed. The T-N and NH4+-N values of the effluent did not generate statistically significant level (p-value:>0.05) when compared with C/N ration values. Removel of nitrogen components form sewage treatment plants were affected by temperature, HRT, SRT and DO. In the case of BOD, all operating factors were affected, while COD was affecte by factors of HRT, STR and DO. In simulations using GPS-X, the parameters that greatly influence was included the maximum sedimentation rate, the dependent nutrient microbial yield (anoxic), the phosphorus saturation coefficient, the dependent nutrient microbial killing rate, the dependent nutrient microbial maximum growth rate, and the independent trophic microorganisms. The maximum growth rate and the maximum setting rate were identified.