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271.
A scalable and efficient key escrow model for lawful interception of IDBC‐based secure communication
Kyusuk Han Chan Yeob Yeun Taeshik Shon Jonghyuk Park Kwangjo Kim 《International Journal of Communication Systems》2011,24(4):461-472
Key escrowing is one of the core technologies for the lawful interception (LI) of secure communications in the wired and wireless networks. Although many previous studies on the key escrowing have been done before, they are insufficient to be deployed in practical networks due to conflicts with the LI requirements. Moreover, there is lack of consideration on the LI of ID‐based cryptosystem (IDBC)‐based secure communication because the interest of the LI was moved to the industries and IDBC has the inherent key escrowing property. However, the inherent property of IDBC cannot prevent ‘illegal’ eavesdropping of all the communications in the networks from the law enforcement agency with the ‘legally’ obtained key. Thus, we propose a new key escrow model that satisfies the requirements of LI and overcomes the potential threats of IDBC. Our contributions enable the scalable and efficient key escrowing for the LI of secure one‐way and two‐pass communication in the mobile networks. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
272.
We have investigated exciton localization in binary GaN nanorods using micro- and time-resolved photoluminescence measurements.
The temperature dependence of the photoluminescence has been measured, and several phonon replicas have been observed at the
lower energy side of the exciton bound to basal stacking faults (I
1). By analyzing the Huang-Rhys parameters as a function of temperature, deduced from the phonon replica intensities, we have
found that the excitons are strongly localized in the lower energy tails. The lifetimes of the I
1 and I
2 transitions were measured to be < 100 ps due to enhanced surface recombination. 相似文献
273.
In-Jin Shon Sung-Yong Kim In-Yong Ko Jung-Mann Doh Jin-Kook Yoon Na-Ra Park 《Metals and Materials International》2011,17(3):445-449
Nanopowders of 3Fe0.67Cr0.33 and Al2O3 were synthesized from CrO3 and 2FeAl powders by high-energy ball milling. A highly dense nanocrystalline 3Fe0.67Cr0.33-Al2O3 composite was consolidated by a high frequency induction heated sintering (HFIHS) method within three minutes from mechanically
synthesized powders of Al2O3 and 3Fe0.67Cr0.33. The average grain size and mechanical properties of the composite were investigated. 相似文献
274.
Hyun-Su Kang In-Yong Ko Jin-Kook Yoon Jung-Mann Doh Kyung-Tae Hong In-Jin Shon 《Metals and Materials International》2011,17(1):57-62
Nanopowders of Fe and ZrO2 were synthesized from Fe2O3 and Zr by high-energy ball milling. The powder sizes of Fe and ZrO2 were 70 nm and 12 nm, respectively. Highly dense nanostructured 4/3Fe-ZrO2 composite was consolidated by a pulsed current activated sintering method within 1 minute from the mechanically synthesized
powders (Fe-ZrO2) and horizontal milled Fe2O3+Zr powders under the 1 GPa pressure. The grain sizes of Fe and ZrO2 in the composite were calculated. The average hardness and fracture toughness values of nanostuctured 4/3Fe-ZrO2 composite were investigated. 相似文献
275.
Na-Ra Park In-Yong Ko Jin-Kook Yoon Jung-Mann Doh In-Jin Shon 《Metals and Materials International》2011,17(2):233-237
Nanopowders of MoSi2 and Si3N4 were synthesized from Mo2N and Si by high ball milling. Dense nanostructured 8MoSi2-Si3N4 composite was consolidated by high frequency induction heated sintering (HFIHS) method within two minutes from mechanically
synthesized powders of MoSi2 and Si3N4. Highly dense 8MoSi2-Si3N4 composite with a relative density of up to 97 % was produced under simultaneous application of 80 MPa pressure and the induced
current. The average grain size and mechanical properties (hardness and fracture toughness) of the composite were investigated. 相似文献
276.
In this study, we compared the line edge roughnesses (LER) and profile angles of chemical vapor deposited (CVD) amorphous carbon (a-C) patterns etched in an inductively coupled plasma (ICP) etcher produced by varying process parameters such as the N2 gas flow ratio, Q (N2), and dc self-bias voltage (Vdc) in O2/N2/Ar and H2/N2/Ar plasmas. The tendencies of the LER and profile angle values of the etched CVD a-C pattern were similar in both plasmas. The LER was smaller in the O2/N2/Ar than in the H2/N2/Ar plasmas, and the profile angle was larger in the O2/N2/Ar than in the H2/N2/Ar plasmas under the same processes conditions. The use of O2/N2/Ar plasma was more advantageous than the H2/N2/Ar plasma for controlling LER and profile angle. 相似文献
277.
An experimental investigation was made to study the effects of chemical coupling of flocculation and adsorption with photocatalysis in treating persistent organic pollutants in wastewater. The photocatalysis alone showed initial reverse reaction when titanium oxide (TiO(2)) was used in catalysis. The effect of the pretreatment of adsorption with powdered activated carbon (PAC) on photocatalysis was studied. The results showed that PAC adsorption followed by photocatalysis was not effective in alleviating reverse reaction. On the other hand, when PAC and TiO(2) were added simultaneously, the reverse reaction was eliminated. Further, the organic removal was also improved by simultaneous PAC and TiO(2) additions. When flocculation with ferric chloride (FeCl(3)) was used as pretreatment, the organic removal efficiency was superior. The initial reverse reaction was also eliminated/minimized. However, inadequate doses of FeCl(3) (less than 30 mgl(-1)) resulted in initial reverse reaction and inferior DOC removal. 相似文献