2型糖尿病血瘀证的Wave Intensity(WI)技术检测

目的:探讨应用Wave Intensity(WI)技术检测临床评估2型糖尿病血瘀证的可行性。方法:用ALOKA Prosoundα10彩色多普勒超声仪,对2型糖尿病65例血瘀证和62例非血瘀证患者,及50例健康者检查,获取W1(前向压缩波)、W2(前向膨胀波)、NA(低振幅负向波)、时间参数(R-W1、W1-W2)等数据。结果:2型糖尿病非血瘀证组的W1值较对照组减低,而血瘀证组W2、NA值较非血瘀证和对照组增高,差异均有显著性意义(P<0.01)。结论:WI技术血流动力学参数为临床综合评估糖尿病患者早期发现动脉硬化提供新方法。

基于Wave Intensity技术的高血压患者动脉弹性参数与血瘀证积分的相关性分析

目的探讨应用Wave Intensity(WI)技术检测高血压患者动脉弹性参数与血瘀证积分的相关性。方法用ALOKA Prosoundα10彩色多普勒超声仪检测119例高血压基础病患者,及62例健康对照者,获取颈总动脉β(僵硬度)、Ep(弹性模量)、AC(顺应性)、AI(增大指数)、PWVβ(β值推导的脉搏波传导速度)、PWV-WI(WI值推导的脉搏波传导速度)等数据,并评估血瘀证积分。结果高血压组β、Ep、AI、PWVβ、PWV-WI均值均高于对照组均值,而AC均值低于对照组均值,两组比较差异有统计学意义(P<0.05),而高血压血瘀证积分与β、Ep、PWVβ、PWV-WI值与呈正相关(分别为r=0.750,P<0.001;r=0.776,P<0.001;r=0.870,P<0.001;r=0.418,P<0.001),与AC呈负相关(r=-0.769,P<0.001),差异有统计学意义,血瘀证积分与AI无明显相关(r=0.023,P=0.800)。结论基于Wave Intensity技术检测的动脉弹性参数能较准确反映血瘀证程度,具有临床应用价值。

高血压患者人迎脉Wave Intensity与脉象参数的相关性研究

目的探讨高血压患者人迎脉(颈总动脉)Wave Intensity(WI)各项参数与脉象仪参数的相关性。方法用ALOKA Prosoundα10彩色多普勒超声仪检测80例高血压病患者,获取右颈总动脉前向压缩波(W1)、前向膨胀波(W2)、低振幅负向波(NA)、僵硬度(β)、β值推导的脉搏波传导速度(PWVβ)、顺应性(AC)、弹性模量(Ep)等数据,应用DDMX-100脉象仪检测右侧寸口脉关部,收集主波高度(h1)、潮波高度(h3)、降中峡高度(h4)、重搏波高度(h5)、脉图收缩期面积(As)、脉图舒张期面积(Ad)等数据。结果基于颈动脉WI[压力瞬时变化(d P/dt)与速度瞬时变化(d U/dt)的乘积,WI=(d P/dt)×(d U/dt)]技术的W1、W2、NA、β、Ep、AC、PWVβ等值与脉象诸参数有显著性相关,但二者反映的信息量及分析方法等存在一定的差异。结论应用WI概念可作为未来脉象领域一个新的研究方向。

Wave Intensity的命名探讨

目的探讨Wave Intensity的中文命名,期望加快该项新技术的临床推广应用。方法查阅文献,结合临床应用体会,通过与传统波强概念对比、时相分析、与加、减速度的关系以及根据检测方法不同命名。结果从不同的研究角度得到不同的命名。结论建议将WI命名为"瞬时波强",简称WI;将W1命名为"瞬时加速度波强",简称W1;将W2命名为"瞬时减速度波强",简称W2,供研究时参考。

高血压血瘀证的Wave Intensity技术检测

目的探讨应用Wave Intensity技术检测临床评估高血压血瘀证的可行性。方法用ALOKA Prosoundα10彩色多普勒超声仪,对高血压65例血瘀证和62例非血瘀证患者,及50例健康者检查,获取W1(前向压缩波)、W2(前向膨胀波)、NA(低振幅负向波)、时间参数(R-W1、W1-W2)等数据。结果高血压非血瘀证组的W1值较对照组增高,而血瘀证组W2、NA值较非血瘀证和对照组增高,差异均有显著性意义(P<0.01)。结论 WI技术血流动力学参数为临床综合评估血瘀证患者的心脏、血管功能提供新方法。

Wave Intensity技术对高血压患者左心室收缩功能和颈动脉血管的研究

目的:探讨WI技术评价高血压患者左心室收缩功能和颈动脉血管的临床应用价值。方法:对56例高血压患者和50例健康志愿者采用高频线阵探头对颈动脉进行检测,应用echo-doppler系统测量颈动脉血流速度和直径变化,计算WI值(W1、W2和NA)、硬化参数(β)、弹性系数(Ep)、顺应性(AC)、增大指数(AI)和脉搏波传导速度(PWVβ、PWV-WI),比较高血压组与对照组各参数值的差异。结果:高血压组与正常对照组相比较W1和W2增高,差异有统计学意义(P<0.05);高血压组β、Ep、PWVβ及PWV-WI较正常对照组增高,AC降低,且差异均有显著性意义(P<0.05)。结论:WI技术能客观准确综合地反映高血压患者左心室收缩功能和血管弹性改变,高血压患者左心整体收缩功能高于健康成人。

Dynamic Stress Intensity Factor and Scattering of SH Wave by Circle Canyon and Crack

The dynamic stress intensity factor (DSIF) and the scattering of SH wave by circle canyon and crack are studied with Green's function. In order to solve the problem, a suitable Green's function is constructed first, which is the solution of displacement fields for elastic half space with circle canyon under output plane harmonic line loading at horizontal surface. Then the integral equation for determining the unknown forces in the problem can be changed into the algebraic one and solved numerically so that crack DSIF can be determined. Last when the medium parameters are altered, the influence on the crack DSIF is discussed partially with the displacement between circle canyon and crack.

Wave Intensity Analysis of Carotid Artery:A Noninvasive Technique for Assessing Hemodynamic Changes of Hyperthyroid Patients

This study examined the wave intensity (WI) of the carotid artery in patients with hyperthyroid in order to assess the hemodynamic changes of hyperthyroid patients.A total of 86 hyperthyroid patients without cardiac morphological changes and arrhythmia, and 80 healthy control subjects were enrolled in the study.Right common carotid artery (RCCA) was selected for ultrasonic imaging to obtain WI indices, including amplitude of the peak during early systole (W1), amplitude of the peak during late systole (W2), area of the negative wave during mid-systole (NA), interval between R wave of electrocardiogram and W1 (R-1st), interval between W1 and W2 (1st-2nd).The levels of serum thyroid hormones, consisting of free triiodothyronine (FT3), free thyroxin (FT4) and thyroid stimulating hormone (TSH), were measured in hyperthyroid patients.Echocardiographic indices including left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were determined in each subject.The results showed that the W1, W2, NA, and (1st-2nd×HR) in hyperthyroid patients were significantly higher than those in healthy controls.There was no significant difference in LVEF and LVFS between the two groups.FT3 was correlated with W1, W2, NA, (1st-2nd×HR), pulse pressure (PP) and heart rate (HR) in hyperthyroid patients.Several abnormal waves on WI curves were present in 19 hyperthyroid patients during mid-systole.It was concluded that WI technique may prove a real-time, noninvasive, sensitive and convenient tool for assessing the cardiac function and hemodynamic alterations in hyperthyroid patients.

THE ESTIMATE AND MEASUREMENT OF LONGITUDINAL WAVE INTENSITY

Quasi-longitudinal waves are one type of structural waves, which are important at high frequencies. This paper studies the estimate theory and measurement technique of quasi-longitudinal waves, analyzes the bias error due to the effect of bending waves. In a two-dimensional quasi-longitudinal wave held, the intensity vector is the sum of the effective intensity vector and the intensity variation vector. Its axial component is proportional to two imaginary parts of cross spectral densities and in the measurement, it is measured by a pair of two-transducer arrays. In a one-dimensional quasi-longitudinal wave field, the intensity variation is zero, the intensity is proportional to only one imaginary part of a cross spectral density and it can be measured using a two-transducer array. If bending and quasi-longitudinal waves coexist and the contribution from bending waves cannot be eliminated or reduced to a certain extent, the measured quasi-longitudinal wave intensity will contain a large error. The results measured on the three-beam structure show that quasi-longitudinal wave intensity can be accurately measured using the intensity technique when bending waves are negligible in comparison with quasi-longitudinal waves.

A Preliminary Study on the Intensity of Cold Wave Storm Surges of Laizhou Bay

Abstract Dike failure and marine losses are quite prominent in Laizhou Bay during the period of cold wave storm surges because of its open coastline to the north and fiat topography. In order to evaluate the intensity of c01d wave storm surge, the hindcast of ma- rine elements induced by cold waves in Laizhou Bay from 1985 to 2004 is conducted using a cold wave storm surge-wave coupled model and the joint return period of extreme water level, concomitant wave height, and concomitant wind speed are calculated. A new criterion of cold wave storm surge intensity based on such studies is developed. Considering the frequency of cold wave, this paper introduces a Poisson trivariate compound reconstruction model to calculate the joint return period, which is closer to the reality. By using the newly defined cold wave storm surge intensity, the ＇cold wave grade＇ in meteorology can better describe the severity of cold wave storm surges and the warning level is well corresponding to different intensities of cold wave storm surges. Therefore, it provides a proper guidance to marine hydrological analysis, disaster prevention and marine structure design in Laizhou Bay.

Effect of Blasting Stress Wave on Dynamic Crack Propagation

Stress waves affect the stress field at the crack tip and dominate the dynamic crack propagation.Therefore,evaluating the influence of blasting stress waves on the crack propagation behavior and the mechanical characteristics of crack propagation is of great significance for engineering blasting.In this study,ANSYS/LS-DYNA was used for blasting numerical simulation,in which the propagation characteristics of blasting stress waves and stress field distribution at the crack tip were closely observed.Moreover,ABAQUS was applied for simulating the crack propagation path and calculating dynamic stress intensity factors(DSIFs).The universal function was calculated by the fractalmethod.The results show that:the compressive wave causes the crack to close and the reflected tensile wave drives the crack to initiate and propagate,and failure mode is mainly tensile failure.The crack propagation velocity varies with time,which increases at first and then decreases,and the crack arrest occurs due to the attenuation of stress waves and dissipation of the blasting energy.In addition,crack arrest toughness is smaller than the crack initiation toughness,applied pressure waveforms(such as the peak pressure,duration,waveforms,wavelengths and loading rates)have a great influence on DSIFs.It is conducive to our deep understanding or the study of blasting stress waves dominated fracture,suggesting a broad reference for the further development of rock blasting in engineering practice.

SCATTERING OF SH-WAVE BY CRACKS ORIGINATING AT AN ELLIPTIC HOLE AND DYNAMIC STRESS INTENSITY FACTOR

The method of complex function and the method of Green's function are used to investigate the problem of SH-wave scattering by radial cracks of any limited length along the radius originating at the boundary of an elliptical hole, and the solution of dynamic stress intensity factor at the crack tip was given. A Green's function was constructed for the problem, which is a basic solution of displacement field for an elastic half space containing a half elliptical gap impacted by anti-plane harmonic linear source force at any point of its horizontal boundary. With division of a crack technique, a series of integral equations can be established on the conditions of continuity and the solution of dynamic stress intensity factor can be obtained. The influence of an elliptical hole on the dynamic stress intensity factor at the crack tip was discussed.

THE ESTIMATE AND MEASUREMENT OF TRANSVERSE WAVE INTENSITY

Transverse waves are a type of structural waves and should be considered in the analysis of high frequency vibration because the energy carried by transverse waves increases with the increase of frequency and becomes important at high frequencies. This paper studies the estimate theory and measuring technique of the transverse wave intensity in two-dimensional homogeneous structures. In general, the intensity vector is the sum of the effective intensity vector and the intensity variation vector. Each axial intensity component is proportional to two imaginary parts of cross spectral densities and its estimate is complicated. For the special case where transverse waves propagate in one direction, the intensity variation is zero and the estimate of the intensity is simplified. The intensity technique is formed based on the finite difference principle. Transverse wave intensity can be measured using a pair of two-transducer arrays lying in the orthogonal direction for the general case or a two-transducer array lying in the propagating direction for the special case. In order to assess the measurement accuracy of transverse wave intensify, the coupling loss factors from bending to transverse waves in building structures were measured using the intensity technique and compared with the results predicted and measured using the conventional method. It is shown that the agreement between the results measured using the intensity technique and that by the conventional method is good.

Effects of Sampling between Data of Significant Wave Height for Intensity and Duration of Severe Sea Storms

The paper deals with the analysis of severe storms in the central Mediterranean Sea and in the US coasts of the Atlantic and Pacific Ocean. Firstly, we introduce a model for the representation of the sea storms by means of two parameters: the former is given by the maximum value of significant wave height in the actual storm and defines the storm intensity, the latter gives the storm duration. The analysis considers buoy data with different sampling Δt between two consecu- tive records, which varies in the range 0.5 - 6 hours. The sensitivity analysis of the modelled sea storm with the varia- tion of Δt shows as the structure of storms is strongly modified with large values of Δt of order of 3 - 6 hours: both the intensity and the duration may change significantly. The results are of interest to investigate the extreme events in the storms obtained with WAve Model, starting from meteorological data, where the value of Δt of 6 hours is widely applied. The conclusion is that structure of severe storms should be represented with continuous data, with Δt = 0.5 hours;a good representation is also obtained with Δt = 1 hour. The errors with increasing values of Δt are investigated.

Measurement of intensity difference squeezing via non-degenerate four-wave mixing process in an atomic vapor

We report the measurement of the intensity difference squeezing via the non-degenerate four-wave mixing process in a rubidium atomic vapor medium. Two pairs of balanced detection systems are employed to measure the probe and the conjugate beams, respectively. It is convenient to get the quantum shot noise limit, the squeezed and the amplified noise power spectra. We also investigate the influence of the input extra quadrature amplitude noise of the probe beam. The influence of the extra noise can be minimized and the squeezing can be optimized under the proper parameter condition. We measure the -3.7-dB intensity difference squeezing when the probe beam has a 3-dB extra quadrature amplitude noise. This result is slightly smaller than -4.1 dB when the ideal coherent light （no extra noise） for the probe beam is used.

Theoretical study of the influence of intense femtosecond laser field on the evolution of the wave packet and the population of NaRb molecule

Employing the two-state model and the time-dependent wave packet method, we have investigated the influences of the parameters of the intense femtosecond laser field on the evolution of the wave packet, as well as the population of ground and double-minimum electronic states of the NaRb molecule. For the different laser wavelengths, the evolution of the wave packet of 6{ }^1／Sigma ^ ＋ state with time and internuclear distance is different, and the different laser intensity brings different influences on the population of the electronic states of the NaRb molecule. One can control the evolutions of wave packet and the population in each state by varying the laser parameters appropriately, which will be a benefit for the light manipulation of atomic and molecular processes.

Seismic effort of blasting wave transmitted in coal-rock mass associated with mining operation

Microseismic effects during the transmission of seismic waves in coal and rock mass associated with mining operation were studied by on-site blasting tests and microseismic monitoring in LW704 of Southern Colliery,Australia,by using spread velocities,amplitudes and frequency contents as the main analysis parameters.The results show that the average P-wave velocity,mean values of combined maximal amplitudes and frequencies of the first arrivals are all reduced significantly along with goaf expanding and intensity weakening of overlying strata during mining process.A full roof fracturing can make the average P-wave velocities,combined maximal amplitudes and frequencies of first arrivals reduce to about 69.8%,92.2% and 60.0%,respectively.The reduction of the above seismic parameters reveals dynamic effects of the variation of strata structure and property to the wave transmission and energy dissipation of blasting wave.The research greatly benefits further study on stability of surrounding rock under the destructive effort by mine tremor,blasting,etc,and provides experimental basis for source relocation and parameter optimization of seismic monitoring as well.

Theoretical research on intensity envelope function of strong ground motion

After the time history of seismic motion is represented by superposition of a series of narrow frequency band wave groups, we obtain a general relation between wave group arrival time and derivative of phase spectra in the paper. On the basis of the relation, frequency number distribution function of wave group arrival time is completely equivalent to that of phase difference spectra. Under the assumption that phase angles of seismic motionobey uniform distribution ranged from 0 to ─ 2π, a quantitative relation between intensity envelope function of seismic motion and energy distribution function with wave group arrival time has been derived in this paper. The relation illuminates inner links among Fourier amplitude spectra and derivative of phase spectra and intensity envelope function. Some examples given by the paper support the conclusions mentioned above.

Photon statistics of pulse-pumped four-wave mixing in fiber with weak signal injection

We study the photon statistics of pulse-pumped four-wave mixing in fibers with weak coherent signal injection by measuring the intensity correlation functions of individual signal and idler fields. The experimental results show that the intensity correlation function of individual signal（idler） field g_（s（i））^（2） decreases with the intensity of signal injection. After applying narrow band filter in signal（idler） band, the value of g_（s（i））^（2） decreases from 1.9 ± 0.02（1.9 ± 0.02） to 1.03 ± 0.02（1.05 ± 0.02） when the intensity of signal injection varies from 0 to 120 photons/pulse. The results indicate that the photon statistics changes from Bose–Einstein distribution to Poisson distribution. We calculate the intensity correlation functions by using the multi-mode theory of four-wave mixing in fibers. The theoretical curves well fit the experimental results.Our investigation will be useful for mitigating the crosstalk between quantum and classical channels in a dense wavelength division multiplexing network.

INTERACTION OF ELASTIC WAVES WITH A PERIODIC ARRAY OF COLLINEAR INPLANE CRACKS

A boundary integral equation method is applied to the study of the interaction of plane elastic waves with a periodic array of collinear inplane cracks.Numerical results are presented for the dynamic stress in- tensity factors.The effects of the wave type,wave frequency,wave incidence angle,and crack spacing on the dynamic stress intensity factors are analyzed in detail.