HMO in study on diffraction-free beams

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Experimental study on phase perception in speech

As the human ear is dull to the phase in speech, little attention has been paid to phase information in speech coding. In fact, the speech perceptual quality may be degenerated if the phase distortion is very large. The perceptual effect of the STFT (Short time Fourier transform) phase spectrum is studied by auditory subjective hearing tests. Three main conclusions are (1) If the phase information is neglected completely, the subjective quality of the reconstructed speech may be very poor; (2) Whether the neglected phase is in low frequency band or high frequency band, the difference from the original speech can be perceived by ear;(3) It is very difficult for the human ear to perceive the difference of speech quality between original speech and reconstructed speech while the phase quantization step size is shorter than π/7.     

A VQ study on diatone in Putonghua

1IntroductionIthasbeenbelievedthatthetonemodelofwordisthebasisoftheintonationmodel,thoughtherearestillsomeargumentsontheintonationmodelsinPutonghua.Inaddition,mostoftheChinesewordsaredisyllables,whichisabout80%ofthetotalChineselexiconstatistically,andmostofwhicharederivativeandcompoundwords.Fromthepointofviewofphonetics,thereare15diatones,exceptthosewithaneutralizedtone.ThebasicphoneticmodelsofdiatonesaregivenbyWu[1]andthepitChvariationmodels,thloughtheacousticandstatisticstudyoffundamentalf…     

Dependence of stresses on grain orientations in BCC polycrystalline films on substrates

Most thin films have different thermal expansion coefficients from their substrates, thus thermal stresses will be introduced into the films when the temperature is changed during annealing and service. Calculations of these stresses for grains in various crystallographic orientations have been made for seven BCC transition metals Cr, Fe, Mo, Nb, Ta, V and W. Neglecting W, which is isotropic and the stresses are equiaxial and without grain orientation （hkl） dependence, the BCC metals may be grouped into two classes. In the first class （Cr, Mo, Nb and V）, the （100）-oriented grains have the largest stresses, while the stresses σ1 and σ2 in other （hkl）-oriented grains decrease linearly with the increase of the angle between （hkl） and （100）, and with σ1 〈 σ2 except in （100）- and （lll）-oriented grains. In the second class （Fe and Ta）, on the contrary, the （100）-oriented grains have the lowest stresses, and the stresses σ1 and σ2 in other （hkl）-oriented grains increase linearly with the increase of the angle between （hkl） and （100）, and with σ1 〉 σ2 except in （100）- and （111）-oriented grains.     

Studies on electron cloud instability in BEPCⅡ

Electron Cloud Instability has been studied in the operation of BEPC. The BEPCⅡ began the commissioning in November 2006 and the positron beam current has reached 500 mA. Because of such a high beam current, some instabilities such as ECI, bunch lengthening et al, have appeared during the operation. The experimental investigation on ECI during the commissioning of BEPCⅡ will be reported in this paper.     

Temperature sensor based on PNR in Sagnac interferometer

A temperature sensor based on polarization non-reciprocity (PNR) in fiber-optic Sagnac interferometer (FSI) was proposed. The experimental study was made primarily and the results agree with theory well. Discussion shows that this kind of temperature sensor can achieve high precision and have great application potential.     

Research on perception of juncturebetween syllables in Chinese

1IntroductionXUYi[l]classifiesjuncturesofChineseinfourcategories'inner-syllablejuncture,between-syllablejuncture,rhythmjuncture,andpausejuncture.Amongthefourcategories,theinner-syllablejunctureisthestrongestone,thebetween-syllablejunctureisthesecond,andtheothertwokindsofjuncturesareweaker.SincemonosyllablesusuallyareadoptedasChinesesyntheticunits,theinner-syllablejuncturehasbeenpreservedinsyllables.Thereforetheinfiuenceofbetween-syllablejunctureonperceptionofnaturalnessofsynthesisChineseisth…     

Effect of Clusters on Thermal Conductivity in Nanofluids

We propose a new model for the effective thermal conductivities of nanottuids, which is derived from the fact that nanoparticles and clusters coexist in the fluids. The effects of the compactness and the perfectness of the contact between nanoparticles in clusters on the effective thermal conductivity of nanofluids are analysed. The proposed model indicates that the effective thermal conductivity of nanofluids decreases with the increasing concentration of clusters. The model predictions are compared with and are in good agreement with the available experimental data.     

Theoretical Study on Ion Escape in Martian Atmosphere

Based on the observation that Martian magnetic moment is gradually reducing from the ancient to the present, we investigate the O^＋ ion flux distribution along magnetic field lines and the ion escaping flux in Martian tail with different assumed Martian magnetic moments. The results show that the O^＋ ion flux along magnetic field lines decreases with distance from Mars; the ion flux along the field line decreases more quickly if the magnetic moment is larger; the larger the magnetic moment, the smaller the ion escaping flux in the Martian tail. The ion escaping flux depends on Z-coordinate in the Martian tail. With decrease of the magnetic moment, the ion escaping flux in the Martian tail increases. The results are significant for studying the water loss from Mars S uFface.     

Effects of traffic noise on pupils''''behavior in classroom

Noise surveys in this country reported that a large number ofclassrooms in primary and secondary schools in the urban areas were dis-turbed by environmental noise,particulariy by traffic noise.A series ofpsychological tests were conducted to identify pupils'behavior in aclassroom under different noise levels within the range of 40 to 70 dBA.Statistical analysis results were obtained by using Relational Data Analy-sis System(RDAS)software.According to the t-test and single factor vari-ance analysis of the results,significant differences of the pupils'behaviorin the classroom have been observed when the percentile exceeded soundlevel either L_(50) exceeds 50 dBA or L_(10) exceeds 55 dBA,or the equivalentcontinuous sound level L_(eq) exceeds 50 dBA.The same conclusion hasbeen drawn from the average percentages of syllable articulation under different noise levels in a classroom which were the results of tests made inacdordance with the procedure described in the National Standard.Themaximum acceptable noise     

Studies on electron cloud instability in BEPCⅡ

Electron Cloud Instability has been studied in the operation of BEPC. The BEPCⅡ began the commissioning in November 2006 and the positron beam current has reached 500 mA. Because of such a high beam current, some instabilities such as ECI, bunch lengthening et al, have appeared during the operation. The experimental investigation on ECI during the commissioning of BEPCⅡ will be reported in this paper.     

A note on ∑ single-particle properties in hypernuclei

Problems of the interpretation of -hypernuclear excitation function related to the single-particle spectrum of -hyperon in the nuclear medium are discussed in Woods-Saxon model.The discussions with J. Hüfner, B. Gyarmati, J. Mare, M. Sotona and K. Yazaki have been of much use and are highly appreciated.     

New approaches inμ + SR studies on critical phenomena in Ni

The critical phenomena in Ni are probed by pulsedSR method under longitudinal- and zero external magnetic fields. The sample magnetization around the critical temperature is confirmed simultaneously by bulk magnetization measurement in situ, disappearance of transverseSR signal and recovery of asymmetry under longitudinal field. At the same time, the ratio of the ⁺ hyperfine field to the bulk magnetization in the ferromagnetic phase below the critical temperature is determined from the observables obtained only in the present experiment. The zero- and low-field longitudinal relaxation rate of muon does not diverge in approaching toT _c in the paramagnetic region, but seems to reach a saturation value.This work is supported by the Grand-in-Aid of the Japanese Ministry of Education, Culture and Science.     

Study on blind band elimination in jitter estimation

We propose a blind spot elimination method based on an improved layout of CCD in spacecraft jitter estimation. At least three CCDs are required and designed with two pairs of overlapping area and one non-overlapping pair. The two number of lines in space of overlapping pairs are made coprime to minimize the number of common blind spots. The third non-overlapping pair is arranged with the space less than the quotient of the least line frequency and bandwidth. It is used to eliminate the aliasing blind frequencies of the first two overlapping pairs. Experimental results prove the effectiveness of the blind band elimination.     

Leptoquark effects on ν τ propagation in the Earth

The proposal of pilgrim dark energy is based on the idea that phantom dark energy possesses enough resistive force to preclude black hole formation. We work on this proposal by choosing an interacting framework with cold dark matter and three cutoffs such as Hubble as well as event horizon and conformal age of the universe. We present a graphical analysis and focus our study on the pilgrim dark energy as well as interacting parameters. It is found that these parameters play an effective role on the equation of state parameter for exploring the phantom region of the universe. We also make the analysis of ω–ω′ and point out freezing region in the ω–ω′ plane. Finally, it turns out that the ΛCDM is achieved in the statefinders plane for all models.     

Study on loss and crosstalk in WDM passive optical network based on spectral slicing

A model for calculating loss and crosstalk in WDM passive optical network based on spectral slicing is proposed in this paper. Through theoretical analysis and numerical calculation, the relationship between loss or crosstalk and the parameters of the system, such as the bandwidth of the light-source, the parameters of the multiplexer, the number of channels and the fraction of channel misalignment, was demonstrated.     

Investigation on the influence of soot size on prompt LII signals in flames

Theoretical papers predict that prompt LII signals are weakly dependent on the soot size due to the fact that larger particles reach higher temperatures during the heating process by nanosecond laser pulses. This question is of crucial importance for establishing LII as a practical technique for soot volume fraction measurements. In this work two-color prompt LII measurements have been performed in several locations of diffusion and rich premixed ethylene-air flames. The experimental apparatus was carefully designed with a probe volume of uniform light distribution and sharp edges, a 4 ns integration time around the signal pulse peak and narrow spectral bandwidth. Measurements did not confirm the theoretical predictions concerning an increase of temperature for larger particles. On the contrary, larger particles in richer premixed flames exhibit a lower 400/700 signal ratio. This can probably be attributed to small differences in the refractive index of soot.     

A ministop band in a single-defect photonic crystal waveguide based on silicon on insulator

This paper reports that a two-dimensional single-defect photonic crystal waveguide in the Г-K direction with triangular lattice on a silicon-on-insulator substrate is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. A ministop band （MSB） is observed by the measurement of transmission characteristics. It results from the coupling between the two modes with the same symmetry, which is analysed from the stimulated band diagram by the effective index and the two-dimensional plane wave expansion methods. The parameter working on the MSB is the ratio of the radius of air holes to the lattice constant, fla. It is obtained that the critical τ/a value determining the occurrence or disappearance of MSB is 0.36. When τ/a is larger than or equal to 0.36, the MSB occurs. However, when τ/a is smaller than 0.36, the MSB disappears.