中药方剂与米非司酮合用治疗子宫肌瘤效果分析

目的中西医结合治疗子宫肌瘤的临床效果。方法选取天津市滨海新区大港医院74例子宫肌瘤患者作为研究对象,采用随机数字表法分为观察组和对照组,对照组给予西药治疗,观察组患者采用中西医结合治疗,对两组患者临床治疗效果进行观察和分析。结果观察组子宫肌瘤患者治疗有效率明显高于对照组(P<0.05),具有统计学意义。结论在子宫肌瘤临床治疗中,采用中西医结合治疗能明显改善临床症状,提高临床治疗效果,安全可靠,具有重要的临床应用价值。     

生产井开发指标的分层分方向定量计算方法

针对注水开发的多层砂岩油藏分层动态分析难度大等问题,在常规井层开发指标计算基础上,结合动、静态劈分方法,综合考虑渗透率、孔隙度、地层系数、含水饱和度、位置系数、措施系数及注水量系数,提出了一种既可将油、水井作为统一整体,又可对小层、方向流动分量开发指标进行定量计算的体现渗流力学本质的方法。用大庆油田N2-O1井组的产液剖面资料进行验证。结果表明,所提方法的计算结果与测量结果吻合度较高,精度平均值达75.11%。用该方法计算开发指标,适用性强,能较真实地反映各小层、各方向的产液情况,对现场应用具有指导意义。     

EEMD在土壤剖面反射光谱消噪中的应用

实测光谱常含有大量干扰信息, 消噪在光谱数据处理和分析中极为重要, 它直接影响后续的定量分析和信息挖掘。因此, 选择适当的消噪方法是改善光谱分析精度, 提升光谱分析能力的一个关键性突破。集合经验模态分解(EEMD)方法是一个以信号固有特征尺度为度量的时空滤波过程, 能充分保留信号本身的非线性和非平稳特征, 在信号的滤波和消噪中具有较大的优势。结合EEMD的多尺度滤波特性, 提出了一种新的EEMD阈值光谱消噪方法, 并应用于新疆塔里木河中游典型绿洲33个土壤剖面反射光谱数据的预处理。为探讨EEMD阈值法在土壤剖面反射光谱消噪中的效用, 对EEMD阈值法和小波阈值法的消噪结果进行了对比分析。结果表明: 与传统的小波阈值法相比, EEMD阈值法消噪结果的信噪比从14.836 6 dB提高到34.275 7 dB, 均方根误差由6.786 1×10-5降到7.240 6×10-6, 相关系数从0.982 5提高到0.999 8, EEMD阈值法的三个消噪效果衡量指标均优于小波阈值法。证明了EEMD阈值法可有效地去除土壤剖面光谱噪声, 较好地保留了光谱的细节信息, 提高了光谱的定量分析精度, 且与小波阈值消噪方法相比具有较强的可靠性和自适应优势, 作为光谱数据预处理的一种新方法, 其应用前景良好。     

《应用声学》2014年总目次 第33卷 第1-6期

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Influence of laser power density on damage of comb by photodynamic therapy—simulation and validation of mathematical models

Photodynamic therapy （PDT） has poor therapeutic outcomes for the treatment of port-wine stain （PWS） lesions with long drug-light intervals （DLIs）. This letter investigates the possibility of improving the treatment efficacy through increasing the laser power density using a computer simulation and a cock comb model. The computational model includes a Monte Carlo simulation for the laser distribution and a calculation of the singlet oxygen concentrations （102）. Both simulation and experimental results show that increasing the power density from i00 to 140 mW/cm^2 not only improves the PDT efficacy, but also results in the unwanted skin damage.     

Even- and odd-order dispersion cancellation effects in four-photon quantum interferometry

The even-order dispersion cancellation effect based on the frequency anti-correlated photon pairs has attracted much attention in the research of quantum dispersion cancellation in two-photon systems. In this letter, we demonstrate a four-photon quantum interferometry in which we can not only observe the even-order dispersion cancellation effect but also the odd-order cancellation. Importantly, the four-photon scheme can get a much better resolution than the two-photon case and help us get a better understanding of the interference phenomenon in a four-photon interferometry.     

Hybrid device for acoustic noise reduction and energy harvesting based on a silicon micro-perforated panel structure

A kind of hybrid device for acoustic noise reduction and vibration energy harvesting based on the silicon micro- perforated panel （MPP） resonant structure is investigated in the article. The critical parts of the device include MPP and energy harvesting membranes. They are all fabricated by means of silicon micro-electro-mechanical systems （MEMS） tech- nology. The silicon MPP has dense and accurate micro-holes. This noise reduction structure has the advantages of wide band and higher absorption coefficients. The vibration energy harvesting part is formed by square piezoelectric membranes arranged in rows. ZnO material is used as it has a good compatibility with the fabrication process. The MPP, piezo- electric membranes, and metal bracket are assembled into a hybrid device with multifunctions. The device exhibits good performances of acoustic noise absorption and acoustic-electric conversion. Its maximum open circuit voltage achieves 69.41 mV.     

Effects of some parameters on the divertor plasma sheath characteristics and fuel retention in castellated tungsten tile gaps

Castellation of plasma facing components is foreseen as the best solution for ensuring the lifetime of future fusion devices. However, the gaps between the resulting surface elements can increase fuel retention and complicate fuel removal issues. To know how the fuel is retained inside the gaps, the plasma sheath around the gaps needs to be understood first. In this work, a kinetic model is used to study plasma characteristics around the divertor gaps with the focus on the H＋ penetration depth inside the poloidal gaps, and a rate-theory model is coupled to simulate the hydrogen retention inside the tungsten gaps. By varying the magnetic field strength and plasma temperature, we find that the H＋ cyclotron radius has a significant effect on the penetration depth. Besides, the increase of magnetic field inclination angle can also increase the penetration depth. It is found in this work that parameters as well as the penetration depth strongly affect fuel retention in tungsten gaps.     

前缘一体化高温热管结构防热效果的实验研究

为了研究复杂构型前缘一体化高温热管结构在高热流密度状态下的防热效果, 设计了飞行器气动加热轨道, 实现了高温热管低状态完全启动、高状态极限考核。然后采用超声速电弧风洞驻点自由射流结合轨道模拟技术, 模拟乘波体飞行器的前缘疏导构件的气动加热环境, 开展了前缘一体化高温热管结构防热效果研究。实验结果表明, 一体化高温热管结构能够多次使用, 低状态下高温热管的启动时间约为115 s, 在高状态下结构依然有效, 降温系数达到24.5%, 验证了前缘疏导式防热结构的防热效果, 可为未来新型高超声速飞行器非烧蚀热防护系统的设计提供指导。      

新型Helmholtz型声子晶体的低频带隙及隔声特性

为了解决军用飞机舱室内产生的低频噪声问题,构建了一种新型的Helmholtz型二维声子晶体,该结构采用迷宫型开口通道,并在结构加入了刚性振子.研究发现,该结构在晶格常数为62 mm条件下,将第一低频带隙的下限降至15 Hz左右,且在100 Hz频率左右形成一条宽度为93 Hz的带隙宽带,表现出较好的低频隔声特性.首先,通过振型及声压场分析了其带隙成因,采用“力-声类比”的方法建立了该结构的等效模型,最后利用有限元法和传递矩阵法对第一低频的带隙范围进行了计算,两种方法所得结果基本相符;其次,通过有限元法探究了晶格常数、空气通道长度及振子材料等结构参数对低频带隙的影响.研究表明,增加开口通道长度和晶格常数都会降低第一带隙下限,增加振子材料密度能够有效降低第二带隙的上下限,进一步揭示了该结构带隙形成的实质,验证了等效模型的准确性.该研究为低频噪声控制方面提供了一定的理论支持,为低频声子晶体的设计提供了新的思路.