• 제목/요약/키워드: Protect Device

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Design of Efficient Hacking Prevention Systems Using a Smart Card (스마트카드 기반의 효율적인 해킹 방지 시스템 설계)

  • 황선태;박종선
    • Journal of Information Technology Applications and Management
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    • v.11 no.2
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    • pp.179-190
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    • 2004
  • This paper describes the design of hacking prevention systems using a smart card. It consists of two parts, i.e., PC authentication and Keyboard-buffer hacking prevention. PC authentication function is a procedure to handle the access control to the target PC. The card's serial number is used for PIN(Personal Identification Number) and is converted into hash-code by SHA-1 hash-function to verify the valid users. The Keyboard-buffer hacking prevention function converts the scan codes into the encoded forms using RSA algorithm on the Java Card, and puts them into the keyboard-buffer to protect from illegal hacking. The encoded information in the buffer is again decoded by the RSA algorithm and displayed on the screen. in this paper, we use RSA_PKCS#1 algorithm for encoding and decoding. The reason using RSA technique instead of DES or Triple-DES is for the expansion to multi-functions in the future on PKI. Moreover, in the ubiquitous computing environment, this smart card security system can be used to protect the private information from the illegal attack in any computing device anywhere. Therefore, our security system can protect PC user's information more efficiently and guarantee a legal PC access authority against any illegal attack in a very convenient way.

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Mechanism of Photodynamic Therapy using 9-hydroxypheophorbide-alpha on HeLa Cell Lines

  • Ahn, Jin-Chul
    • Biomedical Science Letters
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    • v.15 no.2
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    • pp.153-160
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    • 2009
  • Photodynamic therapy(PDT) is a treatment utilizing the generation of singlet oxygen and other reactive oxygen species(ROS), which selectively accumulate in target cells. The aim of present work is to investigate the photodynamic therapy mechanism of 9-HpbD-a-mediated PDT in HeLa cell lines. We studied the general reactive oxygen species(G-ROS) activation after 9-HpbD-a PDT using fluorescence stain with $H_2DCF-DA$. G-ROS activation observed after 9-HpbD-a PDT and higher activation condition was 1 hour after PDT at 0.5 ${\mu}g/ml$ 9-HpbD-a concentration. Sodium azide and reduced glutathione(the singlet oxygen quencher) could protect HeLa cells from cell death induced by 9-HpbD-a PDT. But D-mannitol(the hydroxyl radical scavenger) could not protect cell death. Singlet oxygen played a decisive role in 9-HpbD-a PDT induced HeLa cell death. Type II reaction was the main type of ROS formation at 9-HpbD-a PDT.

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Novel Switching Pattern for the Paralleling of SRM Inverter (SRM 인버터의 병렬 스위칭을 위한 새로운 스위칭 패턴)

  • Lee S. H.;Lee S. H.;Jung S. W.;Lim H. H.;Park S. J.;Ahn J. W.
    • Proceedings of the KIPE Conference
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    • 2002.07a
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    • pp.313-316
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    • 2002
  • A SRM inverter has very low switching frequency. This results in reducing the burden for a high-speed of the gate-amp interface circuit. and the linearity of optocoupler is used to protect the intanteneous peak current for the stable operation In this paper, series resistor is used to equal the current sharing of each switching device and a linear gate-amp is proposed to protect the intanteneous peak current which occurs in transient state.

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A Novel Security Scheme with Message Level Security for Hybrid Applications

  • Ma, Suoning;Joe, Inwhee
    • Annual Conference of KIPS
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    • 2016.04a
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    • pp.215-217
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    • 2016
  • With the popularity of smart device, mobile applications are playing more and more important role in people's daily life, these applications stores various information which greatly facilitate the user's daily life. However due to the frequent transmission of data in the network also increases the risk of data leakage, more and more developers began to focus on how to protect user data. Current mainstream development models include Native development, Web development and Hybrid development. Hybrid development is based on JavaScript and HTML5, it has a cross platform advantages similar to Web Apps and a good user experience similar to Native Apps. In this paper according to the features of Hybrid applications, we proposed a security scheme in Hybrid development model implements message-level data encryption to protect user information. And through the performance evaluation we found that in some scenario the proposed security scheme has a better performance.

New Switching Pattern for the Paralleling of SRM Low Voltage Inverter (저전압형 SRM 인버터의 병렬운전 위한 새로운 스위칭)

  • 이상훈;박성준;원태현;안진우;이만형
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.6
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    • pp.359-367
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    • 2004
  • The switched reluctance motor(SRM) has considerable potential for industrial applications because of its high result lily as a result of the absence of rotor windings. In some applications with SRM, paralleling strategy is often used for cost saving, increasing of current capacity and system reliability. A SRM inverter has very low ,switching frequency. This results in reducing the burden for a high-speed of the gate-amp interface circuit. and the linearity of optocoupler is used to protect the instantaneous peak current for the stable operation. In this paper, series resistor is used to equal the current sharing of each switching device and a linear gate-amp is proposed to protect the instantaneous peak current which occurs in transient state. The proposed paralleling strategy is verified by experimental results.

A Study on the Motor Overload Protection Device (모터 과부하 차단장치에 대한 연구)

  • Kang Byeong Bog;Lim Jung Yeol;Cha In Su;Cho Kyeong Jai;Yoon Suk Am;Lee Jung Il;Seo Jang Soo
    • Proceedings of the KIPE Conference
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    • 2002.11a
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    • pp.209-212
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    • 2002
  • In electrical machinery and apparatus, the most important problem is protect of machinery and apparatus in duo to transient phenomena and overload on operation. Particularly by advanced technology of late, there is demand for low cost of equipments and high percentage of use of equipments. Therefore, protection of machinery and apparatus in condition of overload is more valued considering that all efficiency increase is passed by operating all machinery and apparatus in condition of heavyload. In this paper, the suggested system is add overload protect system using CT in condition of overload.

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Development of Integrity Evaluation Instrument for the Power Line Surge Protective Device (전원용 SPD의 건전성 평가 장치 개발)

  • Chang, Sughun;Kim, Youngjin;Kim, Sungju;Kim, Jaehyung
    • Journal of the Korean Society of Safety
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    • v.30 no.4
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    • pp.39-45
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    • 2015
  • This paper deals with development of integrity evaluation instrument for the power line surge protective device. A reliable power supply is an essential element in the developed information and communication society by highly advances in IT technology. However, the lightning incidence also increased with the recent extreme weather events. In Korea, in order to protect the electrical system from lightning surge, SPD(Surge Protective Device) has been used for these past 30 years. However, the method of diagnosing the safety of the SPD in the industry is insufficient. In this paper, SPD integrity evaluation system was composed of a variable DC power source unit, voltage-current sensor and the embedded controller. In order to measure V-I characteristics of MOV, 3 type samples were degraded by impulse current generator. After impulse tests, the varistor voltage of all samples and nonlinearity coefficient were decreased. It confirmed the utility of the developed equipment by this experimental test and the reliability of SPD is expected for surge accident prevention when applied to industrial plant.

A Study on Convenient Move of Digital Contents Between Devices Using RFID in Home Network (홈 네트워크에서 RFID를 이용한 디바이스 간 디지털 콘텐츠 이동에 관한 연구)

  • Kim, Eun-Hwan;Jung, Yong-Hoon;Jun, Moon-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.2
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    • pp.351-357
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    • 2009
  • Home network is a network composed of devices in home and is being expanded by evolving devices. Also, The number of digital contents in home network has been increasing steadily. But it is difficult to continually protect the rights of digital contents due to lack of interoperability among contents devices. Besides, a license has to be re-issued by DRM sever for contents transfer between devices. Thus, this paper proposes framework which can freely transfer and contents to another device through mutual device authentication and a system that can decrease overload of license management of the DRM sever and that enable device outside home network to use contents through user authentication.

Design of a DC-DC Converter for Portable Device (휴대기기용 DC-DC 부스트 컨버터 집적회로설계)

  • Lee, Ja-kyeong;Song, Han-Jung
    • Journal of Korea Society of Industrial Information Systems
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    • v.22 no.2
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    • pp.71-78
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    • 2017
  • In This Paper, A DC-DC Boost Converter for Portable Device has been Proposed. The Converter Which is Operated with 1 MHz High Switching Frequency is Capable of Reducing Mounting Area of Passive Devices Such as Inductor and Capacitor, Consequently is Suitable for Portable Device. This Boost Converter Consists of a Power Stage and a Control Block and a Protect Block. Proposed DC-DC Boost Converter has been Designed a 0.18 um Magnachip CMOS Process Technology, we Examined Performances of the Fabricated Chip and Compared its Measured Results with SPICE Simulation Data. Simulation Results Show that the Output Voltage is 4.8 V in 3.3 V Input Voltage, Output Current 95 mA Which is Larger than 20~50 mA.

Feasibility Study for Device-to-Device Communications Using Unlicensed Bands in a Cellular Network (셀룰러 네트워크에서 비면허 대역을 활용한 단말 간 직접통신 타당성 연구)

  • Kim, Hyeon-Min;Kang, Gil-Mo;Shin, Oh-Soon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.2
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    • pp.208-211
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    • 2016
  • Device-to-Device communication(D2D) enables devices in proximity to communicate directly without going through the network infrastructure. In particular, D2D communications in a cellular network can improve the spectral efficiency by allowing the reuse of cellular resources. However, it is not easy to maintain the channel quality of the D2D links and to protect the cellular links from the D2D interferences, since the resource allocations for the cellular users will change with time due to the time-varying nature of the cellular channels. To mitigate the performance degradation of D2D links, we propose to exploit unlicensed bands as auxiliary resources when the D2D links share the uplink cellular resources. The effectiveness of the proposed scheme is verified through simulations.