• Title/Summary/Keyword: distributed applications

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Field Applications Study on the Validation of Remediation Technology for Chromium(VI) Contaminated Soil (6가크롬 오염토양 정화기술 현장적용성 연구)

  • Kim, Joo-Young;Choi, Min-Zoo;Kim, Jung-Hoon;Choi, Sang-Il
    • Journal of Soil and Groundwater Environment
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    • v.15 no.1
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    • pp.57-65
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    • 2010
  • Currently, the pursuit of industrialization for rapid economic growth has led to serious environmental damage and related problems because of comtamination with chemicals. Over time, this contaminaion is getting worse and worse. Most developing countries have tried to pursue their economic development and growth, however without preparation for the control and disposal of hazardous wastes. Permitting hazardous waste to be abandoned and disposed in appropriately causes soil pollution, groundwater contamination, and surface water contamination, which are all extremely serious. In particular, when hazardous wastes which include toxic chemicals are distributed around the living environment even in small amounts, concentration can occur in the food chain through ecological systems, which can therefore affect human. Chromium(VI) has contaminated soil in China. We experimented to test the immobilization, chemical reduction, and soil washing methods in order to make our experiment efficient in the purification of soil contaminated with Chromium(VI), and to prove the theoretical models by experiments testing the field applications. The field experiment showed that result of experiment satisfied with the standards of China. The result of multi-stage continuous remediation reduce the Chromium(VI) concentration to 11.95 mg/kg and 14.83 mg/kg that were equivalent to 98% and 97% removal rates. This result implied we could apply multi-stage process of Chromium(VI) contaminated soil to meet the regulatory limit of Chromium(VI).

Method of Fuzzing Document Application Based on Android Devices (안드로이드 기반 문서 어플리케이션의 퍼징 방법론 연구)

  • Jo, Je-Gyeong;Ryou, Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.1
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    • pp.31-37
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    • 2015
  • As the forms of cyberattacks become diverse, there has been reported another case of exploiting vulnerabilities revealed while processing either a document or multimedia file that was distributed for attacking purpose, which would replace the traditional method of distributing malwares directly. The attack is based upon the observation that the softwares such as document editer or multimedia player may reveal inherent vulnerabilities on some specific inputs. The fuzzing methods that provide invalid random inputs for test purpose could discover such exploits. This paper suggests a new fuzzing method on document applications that could work in mobile environments, in order to resolve the drawback that the existing methods run only in PC environments. Our methods could effectively discover the exploits of mobile applications, and thus could be utilized as a means of dealing with APT attacks in mobile environments.

Network Time Protocol Extension for Wireless Sensor Networks (무선 센서 네트워크를 위한 인터넷 시각 동기 프로토콜 확장)

  • Hwang, So-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.12
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    • pp.2563-2567
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    • 2011
  • Advances in smart sensors, embedded systems, low-power design, ad-hoc networks and MEMS have allowed the development of low-cost small sensor nodes with computation and wireless communication capabilities that can form distributed wireless sensor networks. Time information and time synchronization are fundamental building blocks in wireless sensor networks since many sensor network applications need time information for object tracking, consistent state updates, duplicate detection and temporal order delivery. Various time synchronization protocols have been proposed for sensor networks because of the characteristics of sensor networks which have limited computing power and resources. However, none of these protocols have been designed with time representation scheme in mind. Global time format such as UTC TOD (Universal Time Coordinated, Time Of Day) is very useful in sensor network applications. In this paper we propose network time protocol extension for global time presentation in wireless sensor networks.

A Fair Scheduling of Heterogeneous Multi-Server Systems by Cumulative Extra Capacity Sharing (누적적 잉여용량 공유를 통한 이질적 다중 서버 시스템의 공정 스케줄링)

  • Park, Kyeong-Ho;Hwang, Ho-Young
    • The KIPS Transactions:PartA
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    • v.14A no.7
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    • pp.451-456
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    • 2007
  • In this paper, we regard computer systems as heterogeneous multi-server systems and propose a cumulative fair scheduling scheme that pursues long-term fairness. GPS(generalized processor sharing)-based scheduling algorithms, which are usually employed in single-server systems, distribute available capacity in an instantaneous manner. However, applying them to heterogeneous multi-server systems may cause unfairness, since they may not prevent the accumulation of scheduling delays and the extra capacities are distributed in an instantaneous manner. In our scheme, long-term fairness is pursued by proper distribution of extra capacities while guaranteeing reserved capacities. A reference capacity model to determine the ideal progresses of applications is derived from long-term observations, and the scheduler makes the applications gradually follow the ideal progresses while guaranteeing their reserved capacities. A heuristic scheduling algorithm is proposed and the scheme is examined by simulation.

App-based 2-channel User Authentication Scheme for Multiple Application Systems (다중 응용시스템용 앱기반 2-채널 사용자 인증방안)

  • Song, Tae-Gi;Jo, In-June
    • The Journal of the Korea Contents Association
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    • v.18 no.9
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    • pp.141-148
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    • 2018
  • Currently, the user authentication technology used by users to access multiple applications within an organization is being applied with ID/PW-based SSO technology. These user authentication methods have the fundamental disadvantages of ID/PW and SSO. This means that security vulnerabilities in ID/PW can lead to periodic changes in PWs and limits on the number of incorrect PW inputs, and SSO adds high cost of the SSO server, which centrally stores the authentication information, etc. There is also a fundamental vulnerability that allows others to freely use other people's applications when they leave the portal application screen with SSO. In this paper, we proposed an app-based 2-channel authentication scheme to fundamentally eliminate problems with existing ID/PW-based SSO user authentication technologies. To this end, it distributed centralized user authentication information that is stored on SSO server to each individual's smartphone. In addition, when users access a particular application, they are required to be authenticated through their own smartphone apps.

Data Type-Tolerant Component Model: A Method to Process Variability of Externalized Data (데이터 타입 무결성 컴포넌트 모델 : 외부화된 데이터 가변성 처리 기법)

  • Lim, Yoon-Sun;Kim, Myung;Jeong, Seong-Nam;Jeong, An-Mo
    • Journal of KIISE:Software and Applications
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    • v.36 no.5
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    • pp.386-395
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    • 2009
  • Business entities with which most service components interact are kind of cross-cutting concerns in a multi-layered distributed application architecture. When business entities are modified, service components related to them should also be modified, even though they implement common functions of the application framework. This paper proposes what we call DTT (Data Type-Tolerant) component model to process the variability of business entities, or externalized data, which feature modern application architectures. The DTT component model expresses the data variability of product lines at the implementation level by means of SCDTs (Self-Contained Data Types) and variation point interfaces. The model improves the efficiency of application engineering through data type converters which support type conversion between SCDTs and business entities of particular applications. The value of this model lies in that data and functions are coupled locally in each component again by allowing service components to deal with SCDTs only instead of externalized business eutities.

Extensions of LDA by PCA Mixture Model and Class-wise Features (PCA 혼합 모형과 클래스 기반 특징에 의한 LDA의 확장)

  • Kim Hyun-Chul;Kim Daijin;Bang Sung-Yang
    • Journal of KIISE:Software and Applications
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    • v.32 no.8
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    • pp.781-788
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    • 2005
  • LDA (Linear Discriminant Analysis) is a data discrimination technique that seeks transformation to maximize the ratio of the between-class scatter and the within-class scatter While it has been successfully applied to several applications, it has two limitations, both concerning the underfitting problem. First, it fails to discriminate data with complex distributions since all data in each class are assumed to be distributed in the Gaussian manner; and second, it can lose class-wise information, since it produces only one transformation over the entire range of classes. We propose three extensions of LDA to overcome the above problems. The first extension overcomes the first problem by modeling the within-class scatter using a PCA mixture model that can represent more complex distribution. The second extension overcomes the second problem by taking different transformation for each class in order to provide class-wise features. The third extension combines these two modifications by representing each class in terms of the PCA mixture model and taking different transformation for each mixture component. It is shown that all our proposed extensions of LDA outperform LDA concerning classification errors for handwritten digit recognition and alphabet recognition.

Design and Implementation of Interface Middleware for Improved Portability on General Operating System (범용 운영체제의 이식성 향상을 위한 인터페이스 미들웨어 설계 및 구현)

  • Kim, Yeon-Il;Lee, Sang-Gil;Lee, Seung-Il;Lee, Cheol-Hoon
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.17-28
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    • 2015
  • The applications program that running on Operating System has high dependence. Because environment of OS and standard libraries that supports are different. For those reason, Applications that perform the same function should be implemented in accordance with the new operating system. This results in a temporal and economic waste not only in subsequent maintenance of application but also in management. Even though, to solve this problem Cygwin or MinGW has been distributed, they do not support the portability of the application but provide a virtual environment and the tool. Therefore, in this paper, we design the wrapper format interface middleware using the POSIX and standard C library to support the application performing the same function on virtual environment and without code modification. The middleware can be selectively loading the API that is classified by basic and extend. This allows to managing the application size efficiently. Also, perform the comparative experiments and performance evaluation for application, on equipped with the Interface Middleware Linux, Unix, Windows and on Cygwin.

A Design of GPS based Personal Location Self-Control Software on Android Platform (안드로이드 기반 GPS 개인위치정보 자기제어 구조 설계)

  • Jang, Won-Jun;Lee, Hyung-Woo
    • Journal of the Korea Convergence Society
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    • v.1 no.1
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    • pp.23-29
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    • 2010
  • The various kinds of application is distributed for the Smart phone user recently. There is the advantage that the open source application on Android operating system based Smart phone supports a multi tasking service. Layar, Wikitude, and Sherpa and the other applications using the GPS location information like an a2b etc. were developed in the Smart phone environment. However, the existing Cell-ID based location information can be directly collected by the mobile ISP unit which the mobile carrier installs, the personal privacy problem occurs. Therefore, the personal location information is possible to be exposed publicly without any access control procedure. Therefore, in this research, the self-control mechanism on the GPS location information at the Smart phone is designed and presented. Through this, it is possible to develop diverse applications providing enhanced access control and GPS location management on the Android based Smart Phone.

Design and Fabrication of Diplexer for Dual-band GSM/DCS Application using High-Q Multilayer Inductors (고품질 적층형 인덕터를 이용한 이중 대역 GSM/DCS 대역 분리용 다이플렉서의 설계 및 제작)

  • 심성훈;강종윤;최지원;윤영중;윤석진;김현재
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.2
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    • pp.165-171
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    • 2004
  • In this paper, the modeling and design of high-Q multilayer passives have been investigated, and multilayer diplexer for GSM/DCS applications has been designed and fabricated using the passives. Modeling of a multilayer inductor was performed by the subsystems of distributed components, and using the modeling the optimal structures of the high-Q multilayer inductor could be designed by analyzing parasitics and couplings which affect their frequency characteristics. Multilayer diplexers for GSM/DCS applications have been designed and fabricated using LTCC technology. LPF for GSM band had the passband insertion loss of less than 0.55 dB, the return loss of more than 12 dB, and the isolation level of more than 26 dB. HPF for DCS band had the passband insertion loss of less than 0.82 dB, the return loss of more than 11 dB, and the isolation level of more than 38 dB.