Pseudorandomness of Basic Structures in the Block Cipher KASUMI

The notion of pseudorandomness is the theoretical foundation on which to consider the soundness of a basic structure used in some block ciphers. We examine the pseudorandomness of the block cipher KASUMI, which will be used in the next‐generation cellular phones. First, we prove that the four‐round unbalanced MISTY‐type transformation is pseudorandom in order to illustrate the pseudorandomness of the inside round function FI of KASUMI under an adaptive distinguisher model. Second, we show that the three‐round KASUMI‐like structure is not pseudorandom but the four‐round KASUMI‐like structure is pseudorandom under a non‐adaptive distinguisher model.     

Near‐Infrared Light‐Emitting Diodes (LEDs) Based on Poly(phenylene)/Yb‐tris(β‐Diketonate) Complexes

Near‐infrared‐emitting electroluminescent (EL) devices using blue‐light‐emitting polymers blended with the Yb complexes Yb(DBM)₃phen (DBM = dibenzoylmethane), Yb(DNM)₃phen (DNM = dinaphthoylmethane), and Yb(TPP)L(OEt) (L(OEt) = [(C₅H₅)Co{P(O)Et₂}₃]^–) have been studied. EL devices composed of Yb(DNM)₃phen blended with PPP‐OR11 showed enhanced near‐IR output at 977 nm when compared to those fabricated with Yb(DBM)₃phen/PPP‐OR11 blends. The maximum near‐IR external efficiencies of the devices with Yb(DBM)₃phen and Yb(DNM)₃phen are, respectively, 7 × 10^–5 (at 6 V and at 0.81 mA mm^–2) and 4 × 10^–4 (at 7 V, and 0.74 mA mm^–2). The optimal blend composition for EL device performance consisted of PPP‐OR11 blended with 10–20 mol‐% Yb(DNM)₃phen. A device fabricated using Yb‐(TPP)L(OEt)/PPP‐OR11 showed significantly enhanced near‐IR output efficiency, and future efforts will focus on devices fabricated using porphyrin‐based materials.     

A new loss recovery architecture for wireless TCP

The loss recovery architecture of TCP under wireless environment is considered. We propose sent-time ordered two lists architecture as an alternative to sequence number ordered single list architecture. By keeping the sent-time order, the recovery mechanism can be more efficient and-simpler and transmission decision is decoupled from loss recovery using the second list. Simulation results show the superiority of our mechanism.     

The application of microencapsulated phase‐change materials to nylon fabric using direct dual coating method

The fabrication of functional textiles able to provide thermal regulation and comfort for the body has attracted increasing interest in recent years. This research investigated fabric coatings containing energy absorbing, temperature stabilizing, phase‐change material microcapsules (PCMMcs), and their methods of application. Specifically, a coated fabric was directly prepared by a dual‐type coating method, in which the PCMMcs were dispersed in a polyurethane coating solution with no binder. The thermal performances of the dual‐coated samples were evaluated by differential scanning calorimetry, and their physical characteristics were examined by scanning electron microscopy, thermal vision camera, porosity, water vapor transmission rate (WVTR), and water entry pressure (WEP) analyses. Furthermore, the microclimate characteristics of the thermally enhanced fabrics were investigated under experimental conditions using a human‐clothing‐environment (HCE) simulator system. The study results confirmed the superior performance of the dual‐coated fabrics in terms of thermal regulation and body comfort, compared with those coated by the dry or wet coating method, because of the improved WEP, WVTR, and thermal performance. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

CO毒化AB5型合金分形特征研究

研究了三种贮氢合金 L a Ni5、L a Ni4 .7Al0 .3、Ml Ni4 .5Al0 .5被 10 0× 10 - 6 CO毒化后的分形特征 ,求出这三种合金在含 10 0× 10 - 6 CO的氢中循环 ,分维分别为 0 .2 5 4 7、0 .170 9、0 .0 72 5。可以较好的解释合金被毒化的宏观现象。     

Single-photon avalanche diode detectors for quantum key distribution

The application of quantum key distribution (QKD) has raised particular demands for single-photon detectors. One of the most promising candidates at the low-loss optical fibre communications windows is the planar geometry InGaAs/InP single-photon avalanche diode. These detectors have been modelled, fabricated and characterised at 1.55 mum wavelength. Their performance in terms of single-photon detection efficiency, dark count rate, timing jitter and afterpulsing behaviour are reported and compared with the best commercially available, linear multiplication avalanche photodiodes operated in Geiger-mode. Their use in the application of QKD is discussed.     

Atomic force microscopic study on DNA-wrapping for different diameter single-wall carbon nanotubes

DNA-wrapped single-wall carbon nanotubes (DNA-SWNT hybrids) prepared from different diameter HiPco- and Arc-SWNTs were investigated by atomic force microscopy. The mean diameter of DNA-HiPco-SWNT hybrids is 1.94 nm that is consistent with one HiPco-SWNT (~ 0.9 nm) wrapped by DNA (~ 1 nm). On the other hand, the mean diameter of DNA-Arc-SWNT hybrids is 3.74 nm that can correspond to one Arc-SWNT (~ 1.4 nm) wrapped by several layers of DNA. It is suggested that the DNA-wrapping mechanism for large diameter Arc-SWNTs is different from that for small diameter HiPco-SWNTs.