Evaluation Results of the Signal Decomposition Technique for OFDM Transmission which Achieves the Power‐Added Efficiency Improvement and the SNR Enhancement Using the Noise Elimination

The authors have proposed the signal decomposition technique as one of the powerful solution to mitigate the large peak‐to‐average power ratio (PAPR) to be addressed in orthogonal frequency division multiplexing (OFDM) transmitters especially on mobile terminals. In order to enhance the receiver SNR, the simple noise elimination techniques working together with the signal decomposition technique have also been proposed that eliminates the noise added on the decomposed constant amplitude on‐off‐signals taking advantage of the knowledge of their constant amplitude at the receiver. In this paper, we discuss the parameter design issue of the proposed techniques and their optimization. Then, demonstrate the PAPR, the power‐added efficiency (PAE), and also the BER performances operating on the optimized parameters. It is confirmed that the proposed signal decomposition technique improves the PAPR by 4 dB and doubles the PAE at the complementary cumulative distribution function of 1%. It is also confirmed that the proposed noise elimination technique improves the receiver SNR by 3 dB at the BER of 10 to 3, which is nearly equal to that of conventional OFDM, under the conditions that the decomposed signals are transmitted over the independent additive white Gaussian noise channels. Furthermore, it is demonstrated that the proposed techniques work properly when the decomposed signals are transmitted over 2 × 2 multi‐input multi‐output.     

Morphological analyses of minute crystals by using stereo-photogrammetric scanning electron microscopy and electron back-scattered diffraction

We present a new method for the morphological analyses of minute faceted crystals by combining stereo-photogrammetric analysis of scanning electron microscope images and electron back-scattered diffraction. Two scanning electron microscope images of the same crystal, recorded at different tilt angles of the specimen stage, are used to determine the orientations of crystal edges in a specimen-fixed coordinate system. The edge orientations are converted to the indices [ uvw ] in the crystal system using the crystal orientation determined by electron back-scattered diffraction analysis. The Miller indices of crystal facets are derived from the indices of the edges surrounding the facets. The method is applicable to very small crystal facets. The angular error, as derived from tests using a calcite crystal of known morphology, is a few degrees.
To demonstrate the applicability of the method, the morphology of boehmite (γ-AlOOH) precipitated from solution during the dissolution of anorthite was analyzed. The micrometre-sized boehmite crystals are surrounded by two {010} basal facets and eight equivalent side facets that can be indexed equally well as {323}, {434} or {545}. We suggest that these side facets are in fact {111}, the morphology having been modified slightly (by a few degrees) by a small extension associated with opening along (010) microcleavage planes. Tiny {140} facets are also commonly observed.     

j拼音：汉语音节表的新日语标记系统

日本现行的中国固有名词标音没有统一的规则，给日本国内及中日间的信息交流带来了很大的不便和混乱。本基于听写试验的分析结果，通过组合日语固有的基本音节提出了“汉语音节表的新日语标记系统一j拼音”，试图以此来统一日本的中国固有名词标音法。     

Effective Installation Strategies of Fault Current Interrupting Arcing Horns Considering Operational Coordination with Responses of Line Protection Relays

The Fault Current Interrupting Arcing Horns (FCIAH) is a new type of arcing horns, which operates to break fault current within one cycle of alternating current and contributes to reducing the instantaneous power interruption due to the opening of a circuit breaker. However, reportedly the transmission line is often tripped by the line protection relay in some power utilities, even though the FCIAH successfully could break fault current. In this paper, we have investigated primary factors in the unwanted operation of the line protection relays at the current interruption by the FCIAH, and have proposed effective installation strategies of the FCIAH considering the operational coordination with the responses of the line protection relays.     

Corrosion of Silicon Nitride Ceramics in Aqueous Hydrogen Chloride Solutions

The leaching behavior of pressureless sintered and hotpressed Si₃N₄ containing Y₂O₃, Al₂O₃, and AlN and hot isostatically pressed Si₃N₄ without additives was studied in 0.1 M to 10 M HCl aqueous solutions at 50° to 100°C. Y and Al ions contained in the grain-boundary phase dissolved in HCl solutions, but dissolution of the Si ion from the matrix was negligible. The dissolution of Y and Al ions in HCl solutions was adequately described by a surface-chemical-reaction-controlled, shrinking-core model in <1 M HCl solutions and by a diffusion-controlled, shrinking-core model in >5 M HCl solutions. The rates of dissolution of both Y and Al ions decreased as the degree of crystallinity of the grain-boundary phase increased. The fracture strength of the corroded samples linearly decreased with increasing degree of dissolution of soluble Y and Al ions.