摘要：It has been hypothesized that leaflet substrates with a trilayer structure and anisotropicmechanical properties could be useful for the production of functional and long-lasting tissue-engineered *** investigate the influence of the anisotropic structural and mechanical characteristics of a substrate on cells,in this study,we electrospun trilayer anisotropic fibrous substrates and randomly oriented isotropic fibrous substrates(used as controls)from polycaprolactone ***,the random substrates had higher radial and lower circumferential tensile properties than the trilayer substrates;however,they had similar flexural *** valvular interstitial cells cultured on both substrates produced random and trilayer cell-cultured constructs,*** trilayer cell-cultured constructs had more anisotropic mechanical properties,17%higher cellular proliferation,14%more extracellular matrix(i.e.,collagen and glycosaminoglycan)production,and superior gene and protein expression,suggesting that more cells were in a growth state in the trilayer constructs than in the random ***,the random and radial layers of the trilayer constructs had more vimentin,collagen,transforming growth factor-beta 1(TGF-ß1),transforming growth factor-beta 3(TGF-ß3)gene expression than in the circumferential layer of the *** study verifies that the differences in structural,tensile,and anisotropic properties of the trilayer and random substrates influence the characteristics of the cells and ECM in the constructs.

摘要：A kind of erbium doped photosensitive fiber(EDPF) was proposed and fabricated,whose core was made of double layers named photosensitive layer and erbium doped *** double-layer core de-sign can overcome difficulties in fabrication of EDPF with single core design,*** conflict between the high consistency rare earth doping and high consistency germanium doping.A sample was fabri-cated through the modified chemical vapor deposition method combined with solution doping *** peak absorption coefficient was 48.80 dB/m at 1.53 μm,the background loss was lower than 0.1 dB/m,and the reflectivity of the fiber Brag gratings(FBG) written directly on the sample fiber was up to 97.3% by UV-writing ***,a C band tunable fiber laser was fabricated using the sample fiber,in which a uniform FBG was written directly on EDPFs as a reflector.A single wavelength lasing with a maximum wavelength tuning range of 1555.2―1558.0 nm was achieved *** this tuning range,the full-width at half maximum(FWHM) of the laser output was smaller than 0.015 nm and the side mode suppression ratio(SMSR) was better than 50 dB.

摘要：能够根据工作环境改变翼面形状的自适应变形能力是未来航空、航天飞行器结构设计追求的重要目标。研究驱动器布局方式以及控制参数的设计技术是实现该目标的关键。以压电纤维复合薄膜(Macro fiber composites,MFC)作为驱动器,研究在一定数量的MFC驱动器条件下,通过驱动器布局与控制参数的协同设计,以实现类翼面平板结构具有理想形状的最优控制设计方法。以驱动器的铺设位置、铺设角度、层数、对称性以及控制电压为设计变量,以驱动器的击穿电压、铺设位置限制等为约束,建立多参数下的协同优化设计模型。数值算例以类机翼平板的弯曲、扭转、弯扭型面作为理想型面,以实际型面与理想型面在81个参考点位置的均方差为评价指标,设计获得弯曲、扭转和弯扭组合型面的均方差分别为9.977×10–5、4.394×10–4和5.308×10–4,实现了较高的变形控制精度。研究了驱动器数量对变形精度的影响,制作了具有6个驱动器的类翼面平板结构测试平台,仿真与试验结果高度吻合,从而验证了所提出的驱动器布局与控制电压协同优化设计模型的有效性和可行性。

摘要：In this paper we propose an analyzing of the response of a stress optical fiber sensor of which we proposed several design. We show that an optical fiber sensor with these designs can covenanting allow the measuring the force/stress applied to a mechanical structure or which it is linked, by optimizing the uses of appropriate materials for constituting the sensor support. The experiment that we introduce to validate our approach based in principles includes design with a support bearing a multimode optical fiber organized in such a way that the transmitted light is attenuated when the fiber-bending angle coming from stitching in holes of the support is modified by the effects of the force/stress applied to the optical fiber sensor realized in this way. The tests realized concern the most relevant parameters that define the performances of the stress sensor that we propose. We present the problems that we to solved for the optimization of the sensor for selecting the more efficient material for the optical fiber sensor support related to a relevant choice of optical fibers.

摘要：The paper made a research on the fiber Bragg grating sensor demodulation system, which was based on virtual instrument labview and it developed a friendly upper monitor software. Based on the LM algorithm, the software realized rapid and accurate spectral data fitting, improving dynamic characteristics and measuring precision of the system. Depending on different fiber Bragg grating sensors, it can realize flexible calibration. It has the functions of collection, display and data storage, which can flexibly design alarm threshold according to the practical application. The fiber Bragg grating sensors can be identified by the software so that the distributed network, with large capacity optical fiber sensing, can be achieved.

摘要：We demonstrate the use of photonic crystal fiber (PCF) joined in between two single mode fibers (SMF) as a concentration sensor. To realize this, one micrometer length PCF of hexagonal lattice is sandwiched between two SMF having one micrometer length each. To maximize the coupling between SMF and PCF, the core diameters are made equal. Then the output from a given input through this structure is analyzed with respect to different concentrations in the air holes of PCF using Finite Difference Time Domain (FDTD) method. It is found that the variation of electric field intensity at the output is linear with respect to concentration of alcohol.

摘要：We numerically investigate the seven-core photonic crystal fiber (PCF) with the zero dispersion wavelength designed in the range of 1000 - 1080 nm, particularly suitable for the ytterbium-doped fiber laser pumping. Also, the PCFs are well designed for obtaining a flat in-phase mode by carefully adjusting the diameter of inner layer six holes, and the corresponding empirical values of fiber structure are summarized and listed. The variations of inner six holes to the amplitude of in-phase mode are further investigated, and our results show that a better tolerance can be achieved in the fiber structures with lower filling ratio configuration.

摘要：采用自行设计的基于大规模可编程门阵列(FPGA)结构的控制电路,实现了4路光纤激光的多抖动法相干合成。对大气湍流和机械振动引起的相位噪声进行了有效补偿,使远场光斑条纹对比度由开环时的0.21提高到了闭环时的0.93,闭环时远场特定孔径内的能量较开环时提高了3.3倍。该方法还对人为抖动光纤引起的较高频率噪声具有很好的抑制作用,系统闭环后,远场光斑条纹对比度可达到0.72。

摘要：针对单极型马赫曾德尔电光调制器在Radio over fiber(RoF)和副载波复用系统中的应用,讨论了输入两路射频信号的情形,给出了电光调制器互调失真的严格通用解析解。该解析解可用于表示任意阶的互调失真项和谐波项。数值结果表明了该解析解的正确性。分析结果表明,调制器的三阶互调失真与调制器偏置相移无关,只与输入射频信号的调制系数有关,并且当外加偏置电压等于调制器的半波电压时,只存在偶数阶的失真项。根据该解析解,可方便地设计模拟光通信系统,精确地预计外调制器的非线性特征,优化系统性能。

摘要：When trying to fit data to functions of the eigensystem of a pde-eigenvalue problem, such as Maxwell’s equation, numerical differentiation is ineffective and analytic gradients must be supplied. In our motivating example of trying to determine the chemical composition of the layers of specialty optical fibers, the function involved fitting the higher order derivatives with respect to frequency of the positive eigenvalues. The computation of the gradient was the most time consuming part of the minimization problem. It was realized that if one interchanged the order of differentiation, and differentiated first with respect to the design parameters, fewer derivatives of the eigenvectors would be required and one could take full advantage that each grid point was affected by only a few variables. As the model was expanded to cover a fiber wrapped around a spool, the bandwidth of the linearized symmetric eigenvalue problem increased. At the heart of each of the iterative methods used to find the few positive eigenvalues was a symmetric, banded, indefinite matrix. Here we present an algorithm for this problem which reduces a symmetric banded matrix to a block diagonal matrix of 1 x 1 and 2 x 2 blocks. Fillin outside the band because of pivoting for stability is prevented by a sequence of planar transformations. Computationally the algorithm is compared to the block unsymmetric banded solver and the block positive definite symmetric band solver in LAPACK.