• Title/Summary/Keyword: DEF

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Automated Unit-test Generation for Detecting Vulnerabilities of Android Kernel Modules (안드로이드 커널 모듈 취약점 탐지를 위한 자동화된 유닛 테스트 생성 기법)

  • Kim, Yunho;Kim, Moonzoo
    • Journal of KIISE
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    • v.44 no.2
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    • pp.171-178
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    • 2017
  • In this study, we propose an automated unit test generation technique for detecting vulnerabilities of Android kernel modules. The technique automatically generates unit test drivers/stubs and unit test inputs for each function of Android kernel modules by utilizing dynamic symbolic execution. To reduce false alarms caused by function pointers and missing pre-conditions of automated unit test generation technique, we develop false alarm reduction techniques that match function pointers by utilizing static analysis and generate pre-conditions by utilizing def-use analysis. We showed that the proposed technique could detect all existing vulnerabilities in the three modules of Android kernel 3.4. Also, the false alarm reduction techniques removed 44.9% of false alarms on average.

Formalism-Based Defense Safety/Security-Critical Software Development & Certification Criteria - Application of Formal Methods to Safety/Security-Critical Software Certification Process Activities - (정형성 기반 국방 안전/보안필수 소프트웨어 개발 및 인증 기준 - 안전/보안필수 소프트웨어 인증 프로세스에 대한 정형기법 적용 방안 연구 -)

  • Kim, Chang-Jin;Choi, Jin-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.1
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    • pp.55-69
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    • 2007
  • The paper provides the approach to apply formal methods to the development and certification criteria of defense safety/security-critical software. RTCA/DO-178B is recognized as a do facto international standard for airworthiness certification but lack of concrete activities and vagueness of verification/certification criteria have been criticized. In the case of MoD Def Stan 00-55, the guidelines based on formal methods are concrete enough and structured for the defense safety-related software. Also Common Criteria Evaluation Assurance Level includes the strict requirements of formal methods for the certification of high-level security software. By analyzing the problems of DO-178B and comparing it with MoD Def Stan 00-55 and Common Criteria, we identity the important issues In safety and security space. And considering the identified issues, we carry out merging of DO-178B and CC EAL7 on the basis of formal methods. Also the actual case studies for formal methods applications are shown with respect to the verification and reuse of software components.

Pyridoxine Deficiency on Neurotransmitters in the Developing Rat Brain - Catecholamine Metabolism- (Pyridoxine결핍이 뇌의 신경전달물질에 미치는 영향 - Catecholamine 대사 -)

  • Choi, Hay-Mie;Kang, Soon-Ah
    • Journal of Nutrition and Health
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    • v.17 no.3
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    • pp.199-209
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    • 1984
  • Pregnant rats were fed a pyridoxine deficient diet during the gestation and lactation. DEF I group received the deficient diet from delivery ; DEF II group, from the 15 th day of gestation. Body and brain weights, brain protein, DNA, RNA, plasma GOT and GPT, and catecholamines were measured. Effect of MAO inhibiting drug, pargyline, was determined. Brain protein, DNA, and RNA of offsprings of deficient groups were significantly lower than the control group, but RNA/ DNA, brain weight/DNA, and protein/DNA show that cell number were more affected than cell size by the pyridoxine deficiency during the 3rd week of gestation and lactation. Plasma GOT activities were more significantly different than plasma GPT between the control and deficient group. Brain norepinephrine of offsprings of deficient group were significantly lower than the control, but brain dopamine content was not significantly different from the control. At 2nd and 3rd week, norepinephrine was significantly depressed in deficient groups. Pargyline treatment affected a 1.2 fold increase in catecholamines in 3hr while the control had a 1.5 fold increase. Thus norepinephrine and dopamine synthesis was depressed in the deficient groups. Dopaminergic neurons may be less dependent on pyridoxine level than neurons from norepinephrine. Pyridoxine deficiency in maternal diet is not so critical to brain catecholamines of offspring except to the neonatal rats.

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TOPOLOGIES AND INCIDENCE STRUCTURE ON Rn-GEOMETRIES

  • Im, Jang-Hwan
    • Journal of the Korean Mathematical Society
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    • v.39 no.1
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    • pp.31-49
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    • 2002
  • An R$^{n}$ -geometry (P$^{n}$ , L) is a generalization of the Euclidean geometry on R$^{n}$ (see Def. 1.1). We can consider some topologies (see Def. 2.2) on the line set L such that the join operation V : P$^{n}$ $\times$ P$^{n}$ \ $\Delta$ longrightarrow L is continuous. It is a notable fact that in the case n = 2 the introduced topologies on L are same and the join operation V : P$^2$ $\times$ P$^2$ \ $\Delta$ longrightarrow L is continuous and open [10, 11]. It is a fundamental topological property of plane geometry, but in the cases n $\geq$ 3, it is no longer true. There are counter examples [2]. Hence, it is a fundamental problem to find suitable topologies on the line set L in an R$^{n}$ -geometry (P$^{n}$ , L) such that these topologies are compatible with the incidence structure of (P$^{n}$ , L). Therefore, we need to study the topologies of the line set L in an R$^{n}$ -geometry (P$^{n}$ , L). In this paper, the relations of such topologies on the line set L are studied.

Determination Method of Authentication Key Re-Distribution Period in Dynamic En-route Filtering Scheme on WSN (무선 센서 네트워크에서 동적 여과 프로토콜의 인증키 재배포 주기 결정 기법)

  • Lee, Sun-Ho;Cho, Tae-Ho
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.355-358
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    • 2009
  • 센서 네트워크에 대한 연구가 활발히 이루어지면서 센서 네트워크 보안에 대한 문제점이 많이 야기되고 있다. 무선 센서 네트워크에서는 개방된 환경에서 제한적인 자원을 가지는 노드들로 구성되어 있다. 개방된 환경에 배치된 노드들은 공격자에게 쉽게 노출되어질 수 있다. 공격자는 노드를 물리적으로 포획하여 데이터 인증에 사용하는 인증키와 같은 보안 정보들을 획득할 수 있다. 공격자는 포획된 노드를 통하여 허위 보고서로 무선 센서 네트워크에 쉽게 삽입시킬 수 있다. 이는 허위 보고서로 인한 혼란 및 위조 정보의 전달과정에서 발생하는 에너지 고갈 등의 문제점을 유발시키게 된다. 이러한 허위 보고서를 조기에 탐지 및 폐기하기 위하여 동적 여과 프로토콜(DEF: Dynamic En-route Filtering scheme)이 제안되었다. DEF에서 인증키를 재배포 하는 주기는 보안 강도와 비용을 트레이드-오프 하는 관계에 놓여있으므로 매우 중요하다. 본 논문에서는 센서네트워크에서 동적 여과 프로토콜의 인증키 재배포 주기를 결정하는 기법을 제안한다. 배포된 노드들의 위상변화, BS까지 도달한 허위보고서 비율, 공격자에게 포획된 노드의 수 등을 고려하여 재배포 여부를 결정하고 재배포가 결정되면 각 클러스터 헤드들에게 재배포를 명령하게 된다.

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Numerical Study on Characteristics of Turbulence Scheme in Planetary Boundary Layer (난류 모수화 방법에 따른 대기경계층 수치모의 특성에 관한 연구)

  • Jeon, Won-Bae;Lee, Hwa-Woon;Lee, Soon-Hwan
    • Journal of Environmental Science International
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    • v.19 no.2
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    • pp.137-148
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    • 2010
  • This paper investigates the characteristics of turbulence schemes. Turbulence closures are fundamental for modeling the atmospheric diffusion, transport and dispersion in the boundary layer. In particular, in non-homogeneous conditions, a proper description of turbulent transport in planetary boundary layer is fundamental aspect. This study is based on the Regional Atmospheric Modeling System (RAMS) and combines four different turbulence schemes to assess if the different schemes have a impact on simulation results of vertical profiles. Two of these schemes are Isotropc Deformation scheme (I.Def) and Anisotropic deformation scheme (A.Def) that are simple local scheme based on Smagorinsky scheme. The other two are Mellor-Yamada scheme (MY2.5) and Deardorff TKE scheme (D.TKE) that are more complex non-local schemes that include a prognostic equation for turbulence kinetic energy. The simulated potential temperature, wind speed and mixing ratio are compared against radiosonde observations from the study region. MY2.5 shows consistently reasonable vertical profile and closet to observation. D.TKE shows good results under relatively strong synoptic condition especially, mixing ratio simulation. Validation results show that all schemes consistently underestimated wind speed and mixing ratio but, potential temperature was somewhat overestimated.

EPIDEMIOLOGY OF DENTAL CARIES INCIDENCE IN POLIOMYELITIS CHILDREN (소아마비 환자의 치아우식에 관한 역학적 연구)

  • Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.5 no.1
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    • pp.39-43
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    • 1978
  • I have studied on the dental caries incidence of 172 poliomyelitis children who are housed in rehabilitation hospital age from 3 to 13 years compared to a group of normal children. The results were as follows; 1. def rate of the poliomyelitis children was 68.63% (male 66.67%, female 71.43%) and was low value compare with that of control group of 78.64% (M 75.93%, F81.63%). 2. def index per person of poliomyelitis children was 2.37 (M 2.00, F 2.91) and was low in number compare with that of 3.29 (M 3.33, F 3.24) in control group children. 3. DMF rate of the poliomyelitis children was 59.41% (M 54.55%, F 62.79%) and was higher value than that of 48.28% (M 37.88%, F 59.96%) in control group. 4. DMF incidence per person in poliomyelitis was 1.62 (M1.48, F1.89) and was also higher in number than that of 1. 220 (M 0.85, F 1.49) in control group. 5. The dental caries incidence was higher in female than in male.

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Sharing Ship Design Model Based on STEP methodology (STEP 방법론을 이용한 선박설계 모델의 공유)

  • Yong-Jae Shin;Soon-Hung Han
    • Journal of the Society of Naval Architects of Korea
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    • v.35 no.4
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    • pp.98-108
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    • 1998
  • Hull design data is currently prepared by a 2D CAD system and re-input to 3D CAD systems specialized for detail design or to a structural analysis system. In this paper, sharing design data among different CAD systems has been studied. Based on STEP methodology, a neutral model is generated from 2D AutoCAD drawings. To handle a geometric data of this model, the non-manifold model of ACIS is used because it can support various CAD data representation such as 2D graphic entities, 3D wireframe, 3D surface model, and solid B-Rep/CSG model. It is observed that a mon-manifold model can easily be transformed to a 3-D wireframe model for the hull detail design system AutoDef or a FE model for the structural analysis system Nastran.

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Effect of n-3 Fatty Acid Deficiency on Fatty Acid Composition in Brain, Retina and Liver Using a Novel Artificial Rearing System (인공 사육 동물 모델 시스템을 이용한 n-3 지방산 결핍이 쥐의 뇌, 망막, 간의 지방산 조성에 미치는 영향)

  • Lim, Sun-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.4
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    • pp.466-475
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    • 2005
  • Docosahexaenoic acid (22:6n-3, DHA) is highly enriched in membrane of brain and retina, and plays an important role in maintaining an optimal function of the central nervous system. We investigated the effect of n-3 fatty acid deficiency on rat brain, retina and liver fatty acyl composition at two different ages (3 wks and 15 wks) under DHA deficient condition. Rat pups born to dams fed a diet with $3.1\%$ of total fatty acids as $\alpha-linolenic$ acid (LNA) were fed using an artificial rearing system either an n-3 deficient (n-3 Def) or n-3 adequate (n-3 Adq) diet. Both diets contained $17.1\%$ linoleic acid (LA) but the n-3 Adq diet also contained $3.1\%$ LNA. Rats consuming the n-3 Def diet showed a lower brain $(50\%\;in\;13\;wks\;and\;70\%\;in\;15\;wks,\;p<0.05)$ and retinal $(50\%\;in\;13\;wks\;and\;63\%\;in\;15\;wks,\;p<0.05)$ DHA than those on the n-3 Adq diet, which was largely compensated for by an increase in docosapentaenoic acid (22:5n-6, DPAn-6). In the liver of the n-3 Def group, the percentage of DHA decreased by $97\%$ at 3 wks of age with an apparent increase in DPAn-6 relative to the n-3 Adq group (p<0.05), while there was a $65\%$ lower liver DHA in n-3 Def group at 15 wks of age than the n-3 Adq group (p<0.05). Liver arachidonic acid (20:4n-6, AA) was increased at 3 wks of age but decreased at 15 wks of age in the n-3 Def group compared with n-3 Adq group (p<0.05). In conclusion, the replacement of DHA by DPAn-6 in brain and retina fatty acid composition may be related to the suboptimal function in spatial learning, memory and visual acuity. This artificial rearing method presents a first generation model for n-3 deficiency that is similar to the case of human nutrition that commonly employed two generation model.