• 정보보호학회논문지
• /
• 제29권1호
• /
• pp.45-55
• /
• 2019

DEX 파일과, SO 파일로 알려진 공유 라이브러리 파일은 안드로이드 어플리케이션의 행위를 결정짓는 중요한 구성요소이다. DEX 파일은 Java 코드로 구현된 실행파일이며, SO 파일은 ELF 파일 형식을 따르며 C/C++와 같은 네이티브 코드로 구현된다. Java 영역과 네이티브 코드 영역은 런타임에 상호작용할 수 있다. 오늘날 안드로이드 악성코드는 지속적으로 증가하고 있으며, 악성코드로 탐지되는 것을 회피하기 위한 다양한 우회 기법을 적용한다. 악성코드 분석을 회피하기 위하여 분석이 어려운 네이티브 코드에서 악성 행위를 수행하는 어플리케이션 또한 존재한다. 기존 연구는 Java 코드와 네이티브 코드를 모두 포함하는 함수 호출 관계를 표시하지 못하거나, 여러 개의 DEX을 포함하는 어플리케이션을 분석하지 못하는 문제점을 지닌다. 본 논문에서는 안드로이드 어플리케이션의 DEX 파일과 SO 파일을 분석하여 Java 코드 및 네이티브 코드에서 호출 관계를 추출하는 시스템을 설계 및 구현한다.

• 대한기계학회논문집A
• /
• 제30권5호
• /
• pp.488-495
• /
• 2006

The demand for the use of 3D CAD data over the Internet environment has been increased. However, transmission of 3D CAD data has delayed the communication effectiveness because of the CAD data size. Lightweight CAD file design methodology is required for rapid transmission in the distributed environment. In this paper, to derive lightweight CAD files from commercial CAD systems, a file translation system producing a native file is constructed first by using the InterOp and API of the ACIS kernel. Using the B-rep model and mesh data extracted from the native file, the lightweight CAD file with topological information is constructed as a binary file. Since the lightweight CAD file retains topological information, it is applied to the dimensional verification, digital mock-ups and visualization of CAD files. Effectiveness of the proposed lightweight CAD file is confirmed through various case studies.

• 대한임베디드공학회논문지
• /
• 제10권3호
• /
• pp.139-150
• /
• 2015

The major components of IoT(Internet of Things) environment are IoT devices rather than the conventional desktop computers. One of the intrinsic characteristics of IoT devices is diversity in view of data type and data access method. In addition, IoT devices usually deal with real-time data. In order to use such IoT data for internal business or cloud services, an IoT platform capable of easy domain management and consistent data access interface is required. This paper proposes a Linux FUSE-based virtual file system connecting IoT devices on POSIX file system view. It is possible to manage IoT domain with the native Linux utilities such as mkdir, mknod, ls and find in the file system. Also, the file system makes it possible to access or control IoT devices through POSIX interface such as open(), read(), write() or close() without any separate APIs or utilities. A test result shows that the management performance of the file system is lower than that of linux file system negligibly.

• 한국정보과학회논문지:시스템및이론
• /
• 제29권8호
• /
• pp.472-483
• /
• 2002

본 논문에서는 스트리밍 미디어의 효율적인 캐슁과 재전송을 목적으로 범용 화일 시스템에 기반한 사용자 수준의 스트리밍 미디어 캐쉬 화일 시스템(umcFS)을 설계하고 구현하였다. umcFS는 범용화일 시스템의 저장역을 선점하는 화일 디스크에 기반한다. 화일 디스크는 캐쉬 블럭의 물리적인 연속성을 확보하여 효율적인 캐쉬 입출력 시스템을 구성하는 가상 디스크이다. umcFS 구조는 큰 캐쉬 블럭 구조와 제어블럭의 정적 할당을 기본 정책으로 유닉스 화일 시스템과 비교되는 확장된 1차 간접 블럭 참조를 통해서 캐쉬 블럭을 관리한다. 또한 사용자 수준의 라이브러리로 개발되어 시스템 간에 이식성과 확장성이 우수하고 개발 기간이 짧은 장점이 있다. umcFS의 구현을 통해 umcFS의 저수준과 API 수준의 입출력 성능을 비교 분석하였다. 1024KB의 적정 캐쉬 블럭 크기에 대한 임의 입출력 실험 결과, umcFS가 화일 블럭 캐쉬에 비해 약 13%의 성능 향상을 보임을 알 수 있었다.

• 산업경영시스템학회지
• /
• 제26권2호
• /
• pp.23-28
• /
• 2003

This research explains visualization of diagnostic system of 3D CAD data, IGES (Initial Graphics Exchange Specification), by using JNI(Java Native Interface) to connect between C++ and Java programming. The diagnostic system is to analyze IGES clearly by identifying errors and anomalies with respect to the diagnosis of geometry and topology of entities. The output of the system is IGES file including . error information which can be visualized with different colors by several commercial visualization systems. The paper focuses on the visualization of the result IGES which can be extended to web based application over internet.

• 한국CDE학회논문집
• /
• 제7권3호
• /
• pp.202-209
• /
• 2002

It is difficult to support collaborative design with a conventional ship CAD system which manages design information using files. In this research, file storage has been replaced with a database. This paper describes the OpenDIS which is an interface between the geometric kernel and the database. Its main purpose is to implement the CAD system which has the STEP database as the native storage. A prototype CAD system has been implemented using that OpenDIS interface which is implemented by OpenCascade geometric kernel and the Objectstore object-oriented database. The STEP methodology is used as the database schema. This CAD system has been applied to the hull design of a ship in order to verify the usefulness of the interface.

• 대한기계학회논문집A
• /
• 제29권10호
• /
• pp.1353-1360
• /
• 2005

Injection-molded products serve a wide range of applications in our modem lives and their significance is ever increasing. However, difficulty of communication among related companies under the present system results in increase of lead time and decrease of production efficiency. The objective of this paper is the development of a web-based draft verification system in mold design processes. Although several commercial CAD systems offer draft verification functions, those systems are very expensive and inadequate to perform collaborative works. For collaborative work under the distributed environment, the proposed system uses native file transforming of CAD data into optimal format by using the ACIS kernel and InterOp. Functions of draft verification modules are constructed over the ActiveX control using the visual C++ and OpenGL. Therefore, collaborators related to the development of a new product are able to verify the draft and undercut over the Internet without commercial CAD systems. The system helps to reduce production cost, errors and lead-time to the market. Performance of the system is confirmed through various case studies.

• 한국CDE학회논문집
• /
• 제6권4호
• /
• pp.254-262
• /
• 2001

It is not possible to exchange parametric information of CAD (Computer Aided Design) models based on the current version of STEP (Standard leer the Exchange of Product model data). The design intent can be lost during the STEP transfer of CAD models. The ISO Parametrics Group has proposed the SMCH (Solid Model Construction History) schema in June 2000 that includes structures fur exchange of parametric information. This paper proposes the macro parametric approach that is intended to provide capabilities to transfer parametric information. In this approach, CAD models are exchanged in the form of macro files. The macro file contains user commands which are used in the modeling phase. To exchange CAD models using the macro parametric approach, modeling commands of commercial CAD systems are analyzed. Those commands are classified by the grouping method suggested by Bill Anderson. As a neutral file format, a standard modeling commands set has been defined. Mapping relations between the standard modeling commands set and the native modeling commands set of commercial CAD systems are defined.

• 한국CDE학회논문집
• /
• 제7권4호
• /
• pp.240-247
• /
• 2002

Most commercial CAD systems provide parametric modeling functions, and by using these capabilities designers can edit a CAD model in order to create design variants. It is necessary to transfer parametric information during a CAD model exchange to modify the model inside the receiving system. However, it is not possible to exchange parametric information of CAD models based on the cur-rent version of STEP. The designer intents which are contained in the parametric information can be lost during the STEP transfer of CAD models. This paper introduces a hybrid CAB model translator, which also uses the feature tree of commercial CAD systems in addition to the macro file to allow transfer of parametric information. The macro-parametric approach is to exchange CAD models by using the macro file, which contains the history of user commands. To exchange CAD models using the macro-parametric approach, the modeling commands of several commercial CAD systems are analyzed. Those commands are classified and a set of standard modeling commands has been defined. As a neutral fie format, a set of standard modeling commands has been defined. Mapping relations between the standard modeling commands set and the native modeling commands set of commercial CAD systems are defined. The scope of the current version is limited to parts modeling and assemblies are excluded.

• 정보과학회 논문지
• /
• 제44권3호
• /
• pp.232-238
• /
• 2017

사용자 경험이 중요한 스마트폰에서는 사용자의 입력에 대한 응용 프로그램의 반응 시간에 대한 분석이 필요하며 특히 사용자 반응 시간에 큰 영향을 주는 스토리지 I/O 성능의 분석은 사용자 경험최적화를 위한 중요한 요건이다. 사용자가 경험하는 반응 시간의 분석을 위해서는 입력을 받아들이는 최상위 계층에서 최하위 저장장치 계층을 수직적으로 아우르는 통합된 분석도구가 필요한데 기존의 도구들은 제한된 범위의 계층들에 맞추어 있어서 효과적인 사용자 경험 분석이 어려운 상황이다. 본 논문에서는 안드로이드 스마트폰을 대상으로 최상위 안드로이드 플랫폼, 리눅스 커널을 포함하는 전체 스토리지 I/O 계층의 I/O 동작을 측정하고, 이를 바탕으로 계층 통합적 분석을 통하여 각 계층간 I/O 동작을 연결하여 사용자 입력에 따른 스토리지 I/O가 미치는 영향의 분석이 가능한 도구인 AIOPro를 소개한다. 검증 실험을 통하여 AIOPro가 0.1% 미만의 동작부하로 정확히 분석할 수 있음을 확인하였다.