Contribution to Harmonic Depollution Control by the Use of Adaptive Hybrid Filter Type TLC: Case of Control by Modulated Hysteresis

In this article, we propose a topology of a TLC-HAPF power filter as a harmonic compensator for an optimization of the pollution control of electrical networks. This filter consists of an active part and a passive part in order to reduce or limit switching losses during current injection into networks thanks to its TLC module. This topology also provides solutions dynamic performance issues, resonance and lack of compensation capacity for imbalance cases. It also offers a greater range of compensation than conventional active models which do not offer as well as an intermediate circuit voltage in the order of 105 V to 109 V relatively lower than others models (600 v). A modulated hysteresis control of this topology is therefore also developed in this article and allows to obtain a network analysis on the three phases at three levels: source side, load side, and finally at the connection of the filter to the network, allowing to specify for these different positions the value of the current spectrum and its THD at this well-defined moment.

Application of powdered activated carbon coating to fabrics in a hybrid filter to enhance mercury removal

Elemental mercury(Hg0) is predominant constituent of flue gas emitted from coal-fired power plants. Adsorption has been considered the best available technology for removal of Hg0 from flue gas. However, adsorbent injection increases the amount of ash generated. In the present study, powdered activated carbon(PAC) was coated on polytetrafluoroethylene/glass fiber filters to increase Hg0 removal while concurrently reducing the amount of ash generated. The optimal PAC coating rate was determined in laboratory experiments to ensure better Hg0 removal with low pressure drop. When PAC of particle size less than 45 μm was used, and the areal density was 50 g/m2, the pressure drop remained under 30 Pa while the Hg0 removal efficiency increased to 15.8% from4.3%. The Hg0 removal efficiency also increased with decrease in filtration velocity. The optimal PAC coating rate was applied on a hybrid filter(HF), which was combined with a bag filter and an electrostatic precipitator in a single chamber. Originally designed to remove fine particulates matter, it was retrofitted to the flue gas control device for simultaneous Hg0 removal. By employing the PAC coating, the Hg removal efficiency of the HF increased to 79.79% from 66.35%. Also, a temporary reduction in Hg removal was seen but this was resolved following a cleaning cycle in which the dust layer was removed.

Current control for a shunt hybrid active power filter using recursive integral PI

This paper presents a current control method for a shunt hybrid active power filter （HAPF） using recursive integral PI algorithm. The method improves the performance of the HAPF system by reducing the influence of detection accuracy, time delay of instruction current calculation and phase displacement of output filter. Fuzzy logic based set-point weighing algorithm is combined in the control scheme to enhance its robustness and anti-interference ability. The proposed algorithm is easy to implement for engineering applications and easy to compute. Experiment results have verified the validity of the proposed controller. Furthermore, the proposed recursive integral PI algorithm can also be applied in the control of periodic current as in AC drivers.

A “Dressed” Ensemble Kalman Filter Using the Hybrid Coordinate Ocean Model in the Pacific

The computational cost required by the Ensemble Kalman Filter （EnKF） is much larger than that of some simpler assimilation schemes, such as Optimal Interpolation （OI） or three-dimension variational as- similation （3DVAR）. Ensemble optimal interpolation （EnOI）, a crudely simplified implementation of EnKF, is sometimes used as a substitute in some oceanic applications and requires much less computational time than EnKF. In this paper, to compromise between computational cost and dynamic covariance, we use the idea of ＂dressing＂ a small size dynamical ensemble with a larger number of static ensembles in order to form an approximate dynamic covariance. The term ＂dressing＂ means that a dynamical ensemble seed from model runs is perturbed by adding the anomalies of some static ensembles. This dressing EnKF （DrEnKF for short） scheme is tested in assimilation of real altimetry data in the Pacific using the HYbrid Coordinate Ocean Model （HYCOM） over a four-year period. Ten dynamical ensemble seeds are each dressed by 10 static ensemble members selected from a 100-member static ensemble. Results are compared to two EnKF assimilation runs that use 10 and 100 dynamical ensemble members. Both temperature and salinity fields from the DrEnKF and the EnKF are compared to observations from Argo floats and an OI SST dataset. The results show that the DrEnKF and the 100-member EnKF yield similar root mean square errors （RMSE） at every model level. Error covariance matrices from the DrEnKF and the 100-member EnKF are also compared and show good agreement.

Sliding Mode Controller for Three-Phase Hybrid Active Power Filter with Photovoltaic Application

This paper presents a new three-phase hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. This paper will describe the proposed hybrid active power filter control using sliding mode with photovoltaic system. The proposed technique effectively filters harmonics under 1 kHz but also higher frequency to achieve wideband harmonics compensation. The THD of source current is reduced from 30.09% to 1.95%. The result indicates that the sliding mode controller can track the reference signals and have good dynamic characteristics.

Effects of main factors on remedying northern landscaping water by hybrid ecological filter

Natural zeolite and coal cinder were layered as main packing medium of the ecological filter instead of traditional filling to remedy the static lake water in Northern China.The ecological filter was running in a combined upward and downward flow mode.Dynamic experiments were carried out to study the effects of retention time and ambient temperature on pollutants' removal efficiency of the hybrid ecological filter.The function of plant was also studied by contrast test.It is showed that the removal efficiencies of NH4+-N and TP are increased when the retention time is changed from 1 h to 2 h and 4 h,but the removal efficiency of TN is decreased,the removal efficiency of NH4+-N is increased from 91.5% to 98% and that of TP is increased from 31.8% to 52.5%.When the temperature declines,the temporal removal efficiency of NH4+-N is reduced,but the removal efficiency of 24 h and 48 h is remained.The removal efficiency of TP after 24 h and 48 h is decreased when the temperature declines evidently.The retention time plays an important role in NH4+-N and TP removal,and the ambient temperature is significant for TP removal.The plant favors for TP and organic matter removal but has little effect on TN removal.

Research on hybrid power filter of 6 kV power grid in coal mine

Studied the harmonic control of the 6 kV power grid in a coal mine substation.Taking harmonic suppression and reactive power compensation into account, and complyingwith the economic and efficient technical line of the smart grid, a new hybrid activefilter was proposed and applied to the power grid in the coal mine with the advantagessuch as large capacity, low cost and low loss.In order to improve detection speed and reducethe succeeding errors to improve the filtering performance of the active power filter,the DFT (Discrete Fourier Transform) sliding window algorithm based on coordinatetransformation and improved hysteresis control method was proposed.The Matlab simulationresults show that the hybrid active filter is satisfactory, can improve the grid powerfactor and can meet the requirements of improving the power quality in the coal mine.

Multi-sensor Hybrid Fusion Algorithm Based on Adaptive Square-root Cubature Kalman Filter

处于正常操作条件，一个常规方形根的求容积法 Kalman 过滤器(SRCKF ) 给足够地好的评价结果。然而，如果大小不是可靠的， SRCKF 可以给不精密的结果并且到时间分叉。这研究与过滤器获得修正介绍一个适应 SRCKF 算法因为测量的盒子失灵。由建议一个切换的标准，一个最佳的过滤器根据测量质量从适应、常规的 SRCKF 被选择。一个分系统软差错察觉算法与过滤器剩余被造。利用一个清楚的分系统差错系数，有缺点的分系统由于系统重建被孤立。以便改进多传感器系统的性能，一个混合熔化算法基于适应 SRCKF 被介绍。状态和错误协变性矩阵被 priori 熔化估计也预言，并且被分系统的预言并且估计的信息更新。建议算法被用于容器动态放系统模拟。他们与正常 SRCKF 和本地评价相比是加权的熔化算法。模拟结果证明介绍适应 SRCKF 改进分系统过滤的坚韧性，并且混合熔化算法有更好的表演。模拟验证建议算法的有效性。

Decoupling control and zero dynamics stabilization for shunt hybrid active power filter

An inverse system method based optimal control strategy was proposed for the shunt hybrid active power filter(SHAPF)to enhance its harmonic elimination performance.Based on the inverse system method,the d-axis and q-axis current dynamics of the SHAPF system were decoupled and linearized into two pseudolinear subsystems.Then,an optimal feedback controller was designed for the pseudolinear system,and the stability condition of the resulting zero dynamics was presented.Under the control strategy,the current dynamics can asymptotically converge to their reference states and the zero dynamics can be bounded.Simulation results show that the proposed control strategy is robust against load variations and system parameter mismatches,its steady-state performance is better than that of the traditional linear control strategy.

Refinement of Enhanced Speech Using Hybrid-Median Filter and Harmonic Regeneration Approach

This study proposes a post-processor to improve the harmonic structure of a vowel in an enhanced speech, enabling the speech quality to be improved. Initially, a speech enhancement algorithm is employed to reduce the background noise for a noisy speech. Hence the enhanced speech is post-processed by a hybrid-median filter to reduce the musical effect of residual noise. Since the harmonic spectra are impacted by background noise and a speech enhancement process, the quality of a vowel is deteriorated. A harmonic regenerated method is developed to improve the quality of post-processed speech. Experimental results show that the proposed method can improve the quality of post-processed speech by adequately regenerating harmonic spectra.

Preparation and Optical Patterning of Organic-Inorganic Hybrid Color-Filter Films Using Latent Pigments by Utilizing Photo-Acid-Generator and Microwave Irradiation

Preparation and photo-patterning characteristics of organic-inorganic hybrid thin film containing latent pigment by using photo-acid-generator (PAG) and microwave irradiation have been investigated. The acrylic thin film modified with methoxysilane containing PAG was formed on a glass substrate and irradiated with ultraviolet rays to promote sol-gel reaction by catalytic action of acid which was generated from PAG. And then the film was hardened with microwave irradiation, yielding organic-inorganic hybrid polymer film having hardness, highly transparency and strong adhesion with a glass substrate. Since this reaction only occurred in the optically (UV) irradiated regions, by exploiting the difference between the adhesivenesses of these regions photo-irradiated through photomask with a glass substrate, it was possible to form a patterned film with pitch of 100 to 50 μm by a simple lift-off method. A pigment-containing film using latent pigments (with subtractive three primary colors of coloring materials) and a patterned film were prepared, and it was possible to make these films multi-colored by varying the mixing ratio of the pigments. This multi-colored film-preparation method is effective for simply and efficiently forming a color-filter film by applying optical and microwave irradiation.

OPTIMAL SMOOTHING FOR MICROPHONE ARRAY POST-FILTERING UNDER A COMBINED DETERMINISTIC-STOCHASTIC HYBRID MODEL

This paper shows the importance of the optimal smoothing scheme in Microphone Array Post-Filtering(MAPF) under a combined Deterministic-Stochastic Hybrid Model(DSHM).We reveal that some of the well-known MAPF algorithms may cause serious speech distortion without using the optimal smoothing scheme,which is resulted from oversmoothing the raw periodogram over time.Using a minimum conditional mean square error criterion,we derive the optimal smoothing factor under the DSHM,where the Deterministic-to-Stochastic-Ratio(DSR) and the stationarity determine the value of the optimal smoothing factor.The optimal smoothing scheme is applied to the Tran-sient-Beam-to-Reference-Ratio(TBRR)-based MAPF algorithm and experimental results show its better performance in terms of both the Log-Spectral Distance(LSD) and the Perceptual Evaluation of Speech Quality(PESQ).

基于情境感知和序列模式挖掘的气象学习资源推荐算法

随着互联网的快速发展,气象部门职工作为学习者可以获得的学习资源得到极大丰富。信息超载导致检索合适的在线学习资源时遇到了困难;学习者在不同学习环境和序列访问模式上也有不同的学习需求。但是,现有的推荐系统,如基于内容的推荐和协同过滤,没有结合学习者的情境和序列访问模式,推荐结果准确度不高。本文提出了一种结合情境感知、序列模式挖掘和协同过滤算法的混合推荐算法来为学习者推荐学习资源。混合推荐算法中,情境感知被用来整合学习者的情境信息,如知识水平和学习目标;序列模式挖掘被用来对网络日志进行挖掘,发现学习者的序列访问模式;协同过滤被用来根据学习者的情境数据和序列访问模式为目标学习者计算预测并生成建议。实验和应用效果表明,该混合推荐算法推荐的质量和准确性方面优于其他推荐算法。

一种基于粒子群优化BP神经网络技术的震后压埋人员手机定位方法

近年全球地震灾害频发,如何快速准确定位压埋人员方位是震后搜救工作中的重点和难点。本文提出的基于粒子群优化BP神经网络技术震后压埋人员手机定位方法,通过对压埋手机的定位,间接定位到被压埋人员。利用WiFi探针捕捉被压埋手机发出的接收信号强度数据,采用高斯-卡尔曼混合滤波对数据进行处理。以粒子群优化BP神经网络解算出的压埋距离为基础,融合对数衰减模型与多项式衰减模型,建立多衰减模型融合的压埋距离修正模型,获取更为精确的压埋距离。通过加权六点质心定位算法求解压埋手机位置。实验结果表明:多衰减模型融合的压埋距离修正模型定位误差为0.579 m,相较于单一的信道衰减模型与神经网络,定位精度分别提升43.5%、30.9%和12.7%。

高密度椒盐噪声下混合滤波新方法

图像在采集、传输和处理过程中,易受环境、器材及处理方法的影响,不可避免地会产生不同程度的噪声。当噪声密度超过50%时,噪点信息在图像信息中占据主导地位,一般的中值滤波、均值滤波或自适应滤波等单一滤波方式存在着消除噪声的同时滤除了图像自身细节的问题,导致图像不清晰,滤波效果较差。由此提出高密度椒盐噪声下混合滤波新方法,采取降噪、去噪、强化边缘三个层级混合滤波,最后用噪声密度达到80%的图像进行测试验证,有效地滤除了噪声,恢复了图像的细节信息,得到了很好的效果。

一种使用多Filter初始化GA种群的混合特征选择模型

特征选择已经是高维数据处理尤其是模式识别领域中的一个关键问题.提出一种混合特征选择模型用于从潜在的相关特征中选择那些最重要的特征.该模型包括两部分:filter部分与wrapper部分.在filter部分,4种不同的Filter方法分别对候选特征进行独立排序,在融合后进一步生成综合特征排序,综合排序随后产生遗传算法(GA)的初始种群.在wrapper部分,GA算法根据神经网络的分类准确率对个体(特征子集)进行评价,以便于搜索到最优的特征子集.测试结果表明,该模型不仅能有效地减少特征子集的大小,而且还可以进一步提高分类识别的准确率和效果.

基于自适应尺度混合海森滤波器的面部皱纹检测及评分

为解决全面部皱纹缺乏量化评价方法的问题,提出了一种基于自适应尺度混合海森滤波器(adaptive scale hybrid Hessian filter,ASHHF)的面部皱纹检测方法及评分机制。根据受试者年龄自适应调整海森滤波器的尺寸(σ)范围及步长参数并对其面部高分辨率图像进行滤波,基于81个面部特征点在滤波结果中去除五官、背景,仅保留面部皱纹,使用不同颜色将不同深度的皱纹检测结果标注在原始图像中,最后计算得分量化皮肤衰老程度。以专业医生标注皱纹为参考,50名受试者(年龄为22~65岁)的检测结果表明,相比于传统的固定尺度混合海森滤波器(fixed scale hybrid Hessian filter,FSHHF),ASHHF方法的检测准确率平均提升68.57%,运行时间平均缩短26.26%,评分机制结果与检测准确率的变化趋势一致。综上,本文检测方法能够准确、快速检测面部皱纹分布、深度及宽度,所提评分机制能够科学反映受试者皮肤衰老程度,有望为化妆品、医疗美容等抗衰方法提供功效量化评价手段。

基于容忍因子的近似最近邻混合查询算法

近似最近邻搜索(ANNS)是计算机领域中一种重要的高效相似度搜索技术,可用于在大规模数据集中进行快速信息检索。随着人们对高精度信息检索的需求不断增长,同时使用结构化信息和非结构化信息进行混合查询的方式也得到了广泛应用。然而,基于近邻图的过滤贪心算法在混合查询时可能会因结构化约束条件的影响导致连通性降低,进而损害搜索精度。为此,提出了一种基于容忍因子的过滤贪心算法,通过容忍因子控制不满足结构化约束条件的顶点参与路由,在不改变索引结构的前提下维持原有近邻图的连通性,克服了结构化约束条件对检索精度的负面影响。实验结果证明,新算法可以在不同结构化约束强度下实现ANNS的高精度搜索,同时保持检索效率。该研究解决了基于近邻图的ANNS在混合查询场景中的问题,为大规模数据集的快速混合查询信息检索提供了一种有效的解决方案。

基于混合二极管的Sallen-Key低通滤波电路振荡行为研究

设计一种基于混合二极管的Sallen-Key低通滤波振荡电路,将PN结型二极管与电感、电容串并联组合所构成的混合二极管接入低通滤波电路的输入端,构建一种具有复杂动力学行为的混沌振荡电路.引入不对称系数来模拟实际电路中二极管元件之间电学特性的偏差,通过特定参数的相轨迹图、分岔图和Lyapunov指数谱对振荡电路的对称、不对称系数下两种振荡状态进行数值分析.实验产生振荡电路中独特的吸引子共存现象,揭示了受电路参数调节的对称、不对称共存分岔、反单调特性等丰富的动力学行为演化过程.最后,基于FPGA技术完成振荡电路的数字电路实验,验证了数值仿真的正确性和物理可实现性.