Double Filter Research Articles

Parameter identification and SOC estimation for power battery based on multi-timescale double Kalman filter algorithm

Parameter identification and SOC estimation for power battery based on multi-timescale double Kalman filter algorithm

Double spiral chip-embedded micro-trapezoid filters (SMT filters) for the sensitive isolation of CTCs of prostate cancer by spectral detection.

Circulating tumor cells (CTCs) are cancer cells that are released from the original tumor and circulate in the blood vessels, carrying greatly similar constituents as the original tumor. Therefore, CTCs have a significant value in cancer prognosis, early diagnosis, and anti-cancer therapy. However, their rarity and heterogeneity make the isolation of CTCs an arduous task. In the present research, we propose a double spiral chip-embedded micro-trapezoid filter (SMT filter) for the sensitive isolation of the CTCs of prostate cancer by spectral detection. SMT filters were elongated to effectively capture CTCs and this distinctive design was conducive to their isolation and enrichment. The SMT filters were verified with tumor cells and artificial patient blood with a capture efficiency as high as 94% at a flow rate of 1.5 mL h-1. As a further validation, the SMT filters were validated in isolating CTCs from 10 prostate cancers and other cancers in 4 mL blood samples. Also, the CTCs tested positive for each patient blood sample, ranging from 83-114 CTCs. Significantly, we advanced hyperspectral imaging to detect the characteristic spectrum of CTCs both captured in situ on SMT filters and enriched after isolation. The CTCs could be positively identified by hyperspectral imaging with complete integrity of the cell morphology and an improved characteristic spectrum. This represents a breakthrough in the conventional surface-enhanced Raman scattering (SERS) spectroscopy of nanoparticles. Also, the characteristic spectrum of the CTCs would be highly beneficial for distinguishing the cancer type and accurate for enumerating tumor cells with varied intensities. Furthermore, a novel integrated flower-shaped microfilter was presented with all these aforementioned merits. The success of both the SMT filters and characteristic spectral detection indicated their feasibility for further clinical analysis, the evaluation of cancer therapy, and for potential application.

A novel filter for removing image noise and improving the quality of image

This paper proposed a hybrid wavelet double window median filter (HWDWM) which is made by blending decision-based coupled window median filter and discrete wavelet transform (DWT) and review is made to increase the filters which are widespread for removing noise. In the proposed filter there are double window such as row window and column window. This proposed method takes the noisy image for processing and it moves row window for indexing from the 1st pixel of the noisy image up to the last pixel of the noised image then indexing is made by column window then decompose the signal of the image to provide the localisation. The noisy image is decomposed by DWT and then coefficients are transformed to independent distributed variables. The coefficients are then analysed on the basis of thresholding. The image is reconstructed using wavelet transform's inverse after the threshold. Experiments were executed in order to show the effect of noise removal filters on soil image. Two metrics are used to measure the quality of image; they are: peak signal to noise ratio (PSNR) and root mean square error (RMSE). Experimental results show the superiority of this filter over other noise removal filters.

Parameter identification and SOC estimation for power battery based on multi-timescale double Kalman filter algorithm

Accurate modelling and state of charge (SOC) estimation are of great significance to improve efficiency of power batteries and extend their life. In order to solve the issue of time-varying model parameters resulting in inaccurate SOC estimation, a combined online identification of model parameters and SOC estimation method for lithium-ion batteries based on extended Kalman filter (EKF) and unscented Kalman filter (UKF) with different timescales is proposed. A second-order RC circuit model is established and model parameters are identified online by UKF on a macroscopic timescale, and the battery SOC is estimated by EKF on a microscopic timescale. Compared with conventional SOC estimation methods in which model parameters are identified offline, the proposed method can obtain more accurate SOC estimation. The SOC mean absolute error (MAE) and root mean square error (RMSE) are both significantly reduced under the urban dynamometer driving schedule (UDDS) test. The SOC estimation results demonstrate the accuracy and robustness of the proposed method.

Remaining Useful Life Prediction of Rolling Bearings Based on Segmented Relative Phase Space Warping and Particle Filter

Predictive maintenance plays a crucial role in the field of intelligent machinery fault diagnosis, which improves the efficiency of maintenance. This paper focuses on the extraction of real-time damage feature and the prediction of remaining useful life (RUL) in predictive maintenance of rolling bearings. Some RUL prediction approaches lack dynamic foundations and require large amounts of data and prior knowledge. This paper proposes the algorithm of segmented relative phase space warping (SRPSW) and a strategy combining double exponential model (DEM) and particle filter (PF) to predict the RUL. SRPSW provides a dynamic basis for real-time RUL prediction in different stages. The DEM-based PF reduces the need for prior knowledge and improves accuracy. The analysis results from normal and accelerated degradation experiments show that the proposed SRPSW overcomes the failure of the original PSW in depicting the later operating stage of bearings. Further, the relative damage indicators (RDIs) extracted by SRPSW are more accurately than commonly used indicators. The predicted results show that the DEM-based PF does not require professional and prior information whilst ensuring the accuracy of RUL prediction. The proposed approach in this paper provides a new avenue for predictive maintenance of bearings.

Electric Vehicle State Parameter Estimation Based on DICI-GFCKF

To improve the estimation accuracy of the state parameters of distributed electric vehicles, a double inverse covariance intersection generalized fifth-order cubature Kalman filter (DICI-GFCKF) es-timation algorithm is proposed. Based on the fifth-order cubature Kalman filter algorithm, the generalized cubature rule is used to directly obtain the weight and cubature point of the algorithm. Then, the inverse covariance intersection (ICI) data fusion algorithm is introduced and combined with the generalized fifth-order CKF, and the double inverse covariance intersection-generalized fifth-order cubature Kalman filter is derived. The algorithm is applied to estimate the state parameters of distributed electric vehicles. Finally, the simulation and the vehicle experiment show that the algorithm not only improves the estimation accuracy and stability but also reduces the influence of the system model nonlinearity on the algorithm, and has good effectiveness and robustness.

An Integrated Double Hybrid Fusion Approach for Image Smoothing

Often in practice, during the process of image acquisition, the acquired image gets degraded due to various factors like noise, motion blur, mis-focus of a camera, atmospheric turbulence, etc. resulting in the image unsuitable for further analysis or processing. To improve the quality of these degraded images, a double hybrid restoration filter is proposed on the two same sets of input images and the output images are fused to get a unified filter in combination with the concept of image fusion. First image set is processed by applying deconvolution using Wiener Filter (DWF) twice and decomposing the output image using Discrete Wavelet Transform (DWT). Similarly, second image set is also processed simultaneously by applying Deconvolution using Lucy–Richardson Filter (DLR) twice followed by the above procedure. The proposed filter gives a better performance as compared to DWF and DLR filters in case of both blurry as well as noisy images. The proposed filter is compared with some standard deconvolution algorithms and also some state-of-the-art restoration filters with the help of seven image quality assessment parameters. Simulation results prove the success of the proposed algorithm and at the same time, visual and quantitative results are very impressive.

Experimental justification of directions for improving the methodological support of professional psychological selection of candidates for training in universities of the ministry of defense of the Russian Federation

This experimental study aimed to determine the possibility to increase the effectiveness of predicting the success of training and military-professional adaptation by applicants to universities of the Russian Federation Ministry of Defense by including professional psychological selection, an indicator of previously unused psychological survey methods and complex visual-motor reaction. Therefore, we examined the cadets of the VVI courses and used the results of the same groups of cadets when they pass the professional psychological selection. Mathematical and statistical data processing was carried out by discriminant analysis. The long-term forecast of successful training according to the professional psychological selection indicators is ineffective, and 61.7% of cadets have high academic performance. The inclusion of complex visual-motor reaction indicators significantly increases the reliability of the long-term forecast of high academic performance to 85.7%, overcoming the critical threshold of 75%. Additionally, by the end of the training, 10%12% of cadets developed chronic stress-induced somatic diseases, such as circulatory system (I00I99 according to the International Statistical Classification of Diseases and Related Health Problem 10th revision) and digestive system diseases (K00K93), indicating imperfect military-professional adaptation and reducing the professional activity reliability. Adding the study of complex visual-motor reaction indicators and a method that evaluates the neurotic manifestations to the existing tests in the professional psychological selection procedure is necessary to predict the propensity to stress-induced somatic diseases. The indicators in the prediction models of academic performance and propensity to stress-induced somatic diseases are different, which reflects the significant difference in their biopsychosocial mechanisms. Placing a double filter in the decisive selection rule is necessary to identify people with a forecast of high academic performance and identify stress-resistant people who are not prone to stress-induced somatic diseases among them. Developing weighting coefficients of every test block is necessary to conclude; however, the existing approach is assumed to be equivalent, that is, at variance with the complex biopsychosocial mechanism of professional reliability.

Biological Network Inference With GRASP: A Bayesian Network Structure Learning Method Using Adaptive Sequential Monte Carlo.

Bayesian networks (BNs) provide a probabilistic, graphical framework for modeling high-dimensional joint distributions with complex correlation structures. BNs have wide applications in many disciplines, including biology, social science, finance and biomedical science. Despite extensive studies in the past, network structure learning from data is still a challenging open question in BN research. In this study, we present a sequential Monte Carlo (SMC)-based three-stage approach, GRowth-based Approach with Staged Pruning (GRASP). A double filtering strategy was first used for discovering the overall skeleton of the target BN. To search for the optimal network structures we designed an adaptive SMC (adSMC) algorithm to increase the quality and diversity of sampled networks which were further improved by a third stage to reclaim edges missed in the skeleton discovery step. GRASP gave very satisfactory results when tested on benchmark networks. Finally, BN structure learning using multiple types of genomics data illustrates GRASP’s potential in discovering novel biological relationships in integrative genomic studies.

Influence of double layer filter on mean glandular dose (MGD) and image quality in low energy image of contrast enhanced spectral mammography (LE-CESM)

IntroductionThe aim of this study was to evaluate mean glandular dose (MGD) and image quality in low energy imaging from contrast-enhanced spectral mammography (CESM) when using double-layer filtration. MethodologyA dedicated phantom was used to quantitatively estimate the MGD and image quality. The target slab of the phantom consisted of three iodine coins having a concentration of 1.0 mgI/cm3, 2.0 mgI/cm3, 4.0 mgI/cm3, a 100% adipose equivalent coin and a 100% glandular equivalent coin. The phantom was exposed using a semiautomated function at 28 k, 30 kV and 32 kV. MGD. Contrast to noise ratio (CNR) and figure of merit (FOM) were estimated for Mo/Rh, Mo/Rh + Cu, Mo/Rh + Al and Mo/Rh + Cd combinations using three breast equivalent compositions. ResultsMGD was reduced up to a maximum of 1.03 mGy from 1.17 mGy for 100% adipose tissue. 1.18 mGy from 1.34 mGy for 50% glandular tissue and 1.39 mGy from 1.72 mGy for the 100% glandular phantom when using double-layer filtration. All of the above-mentioned results were obtained for the 50 mm phantom using 32 kV. CNR and FOM values were not significantly reduced with a double-layer filter when compared to a single-layer filter. ConclusionThe present study concluded that Mo/Rh + Cu is the best combination to reduce the MGD significantly when compared to Mo/Rh + Al or Mo/Rh + Cd. Mo/Rh + Cu also achieved optimal image quality when compared to the Mo/Rh single filter combination. Implications of practiceThe use of a double-layer filter in low energy imaging of CESM results in a significant reduction in MGD without degrading the quality of the image.

OR15. Cell Surface Markers on Adipose-Derived Mesenchymal Stem Cells: Isolation, Culture, and Identification for Translational Success

Abstract Aims The purpose of this study is determining that each part of adipose tissue will generate stem cells with similar adipose-derived mesenchymal stem cells (AMSCs) characteristic and specific cell-surface markers, thus there is no waster product of part adipose tissue in regenerative medicine. Methods An invitro experimental study, used approximately 20 grams of human subcutaneous adipose tissue were isolated and processed, until stromal vascular factor (SVF) and creamy supernatant separated. Both substances then divided into single filtration group and double filtration group consecutively. Each group and control group were sextuplicate before further analysis using immunocytochemistry. Single and double filter of AMSCs were applied to the subsequent experiments. AMSCs were observed under a microscope, the growth curves of the cells were assessed using a cell counting kit‑8 assay and the membrane expression of cell surface antigens, including cluster of differentiation (CD) 34, CD45, CD90, and CD105 were detected by immunocytochemistry. Results Flow cytometry demonstrated that the cells were highly positive for fourth cell surface markers. CD34 and CD45 expressions were detected in control group, and gradually decreased among another groups whereas lack of CD45 expression were consistent on other remaining groups. The expression of CD90 and CD105 were visibly increased significantly from control group to fourth group. Conclusion This study demonstrated that either SVF and/or supernatant generates fibroblastic-like cells and surface markers expression that matched the MSCs criteria. Therefore, all parts of adipose tissue are an appealing alternative of stem cell source regardless of culture method chosen.

A defect-rich layered double hydroxide nanofiber filter with solar-driven regeneration for wastewater treatment

The need for environmental technology treatment of contaminants of emerging concerns (CECs) is increasing as CECs lead to detrimental effects on human health and ecosystems. Herein, defect-rich layered double hydroxide (LDH) structured into a fibrous filter with a facile solar-driven regeneration function was fabricated for efficiently removing adsorbed CECs in wastewater. The physical and chemical interactions between the LDH filter and CECs are revealed. It is demonstrated that the introduction of unsaturated Cuδ+ sites (δ < 2) and creating oxygen vacancies represents an effective way for improving adsorbing activity of the defect-rich LDH host layer. Also, the nanofiber-particle friction coefficient of the hierarchical LDH filter affects the filtration efficiency as revealed by 3D modelling. The LDH filter is capable of filtrating sixteen types of CECs and shows the capability of photocatalytic degradation of adsorbed CECs, thus enabling filter regeneration. This work thus presents a new perspective into bottom-up design of adsorbent materials: from molecular interactions to shaping adsorbents into microscopic nanofibers and assembling these into macroscopic 3D adsorbent filters.

The Association between Vitamin D Deficiency and Chronic Tonsillitis in Children: an Evidence Based Case Reports

Background: vitamin D has an important influence on the host’s immune system by modulating both innate and adaptive immunity and regulating the inflammatory cascade. Vitamin D deficiency may be related with reduced immunomodulation, specifically in preventing the occurrence of chronic tonsillitis.&#x0D; Objective: to identify the association between vitamin D deficiency with chronic tonsillitis in pediatric patients.&#x0D; Methods: the search was conducted with advanced searching on PubMed® and Cochrane® according to the clinical question. The screening of title and abstract using inclusion and exclusion criteria, double filter, and reading full text led to six useful articles. The selected studies were critically appraised for validity, importance, and applicability. &#x0D; Results: three original articles were eligible for this evidence-based case report. All studies were considered to have good validity. All three studies reported an increased risk of chronic tonsillitis with the vitamin D deficiency and/or insufficiency.&#x0D; Conclusion: Vitamin D deficiency may be associated with the increased risk of chronic or recurrent tonsillitis in children.

Practical Method for Prevention of Fat Embolism in Mechanical Stromal Cell Applications: IPs and IV Blood Transfusion Set.

Recently, obtaining stromal cells mechanically from adipose tissue has become very popular in plastic surgery. Mechanical methods are advantageous in terms of not only regulatory considerations but also of the application (cost, quality, and quantity) of the products obtained compared with the use of enzymes. In a study conducted by Ghiasloo et al, 4505 articles were reviewed, and it was noted that mechanical methods are used in many indications.1 Copcu and Oztan examined a total of 276 studies and found 46 different terms to define the end product from mechanical methods.2 Stromal vascular fraction is an enzyme-specific definition; the authors suggested total stromal cells (TOST) instead of stromal vascular fraction for the end product resulting from mechanical methods.2 As shown in recent studies, TOST is used in many indications, such as stromal vascular fraction.1,2 Although there are no complications related to the mechanical methods described so far, the most important potential complication is fat embolism. There is always a possibility of adipose tissue or fat globules in the final product obtained. To minimize or eliminate this risk, it is necessary to ensure that the final product is in liquid form in cases in which it is possible to enter the systemic circulation and pass through a double filter (filter in filter) in the obtained liquid.3 For this purpose, the indication-based protocols (IPs) defined by Copcu and Oztan should be followed in mechanical stromal-cell transfer.4 If the final product is to be obtained in liquid form, the condensed fat should be diluted with an appropriate liquid (saline, ringer, platelet-poor-plasma, etc.) and mechanical separation should be performed. Copcu speculated that this approach would yield more stromal cells, especially due to polarity and cellular interaction.5 In IP one, 10 cm3 condensed fat is mixed with 10 cm3 saline or similar liquid, and in IP two, 5 cm3 fat is mixed with 5 cm3 liquid and mechanical separation is achieved. To prevent embolism of TOST in liquid form, an IV transfusion with a double-filter system should be used. Today, two types of filters are used in transfusion sets: 170–200 μm filters for macroaggregates and 15–40 μm filters for microaggregates.3 Fat cells are normally 80–120 μm in size if they are not hypertrophied.3 Hypertrophied cells are retained by the macroaggregate filter and the rest by the microaggregate filter. Therefore, we use the IV set presented in Figure 1 and in the video. (See Video [online], which displays the preparation of mechanical stromal-cells). Stromal cells vary in size from 8 to 12 μm. A 25-μm filter both minimizes risk and ensures a safe delivery of stromal cells. However, the most important approach here is to obtain TOST in liquid form to prevent possible circulation of extracellular matrix and adipose tissue particles when using mechanical methods; this can only happen with IPs. Especially in the method defined as supercharged mechanical stromal-cell transfer, the addition of platelet-rich-plasma after processing the condensed fat with platelet-poor-plasma first makes it possible not only to collect approximately five times more cells but also to give both fat- and blood-derived regenerative cells, and to apply regenerative cells in a much wider spectrum. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 1.","caption":"Mechanical Stromal-cells Prep. Video 1 from “Practical Method for Prevention of Fat Embolism in Mechanical Stromal Cell Applications: IPs and IV Blood Transfusion Set.” This video displays the preparation of mechanical stromal-cells with IPs and IV filters","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_66j4389w"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Fig. 1.: Preparation of filters for prevention of fat embolism in mechanical stromal-cell applications. A, IV blood transfusion set with 170-μm filter for macroaggregate and 25-μm filter for microaggregate. B, Filters. C, Practical set for prevention of fat embolism in mechanical stromal-cell transfer.DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. No funding was received for this article.

A robust node-shifting method for shape optimization of irregular gridshell structures

Evolutionary node shifting is an effective approach to the shape optimization of spatial structures for excellent mechanical performance. In this paper, a novel shape optimization algorithm is proposed, which is applicable to complex gridshell structures of irregular geometries and non-uniform grids. With the objective of maximizing the structural stiffness, the nodal coordinates are iteratively updated according to the sensitivity information. The perturbation displacements referring to the inverse hanging method are applied to the initial flat model. By analysis, we found that the irregular grids give rise to non-smooth gradient fields, which results in jagged surfaces. To normalize the non-smooth gradient fields and to prevent the optimization process from falling into local optima, a double filter scheme is introduced in the process of optimization. A variety of examples are presented to demonstrate that the proposed algorithm can effectively solve shape optimization problems of general gridshell structures.

Multi-wavelength switchable random fibre laser based on double Sagnac-loop filter

A multi-wavelength switchable random fibre laser based on a double Sagnac-loop filter is proposed. The threshold of laser is 27 mW and the slope efficiency of the total power output to pump power is about 0.04%. In the experiment, stable and switchable laser outputs of single-, dual-, tri- and quad-wavelength channels are obtained by adjusting the polarization controller at room temperature. The wavelength positions are tuneable within the range of 1556–1564 nm and intervals are switchable between 2.5, 5 and 7.5 nm. Under 300 mW pump power, average power intensity of −24dBm is achieved. Furthermore, the output of fibre laser is relatively stable with less than 0.2 nm wavelength drift and less than 1.5 dBm power fluctuation within one hour. The proposed random fibre laser has promising application prospects for distributed sensing systems and biomedical imaging.

The Traffic Sign Detection Algorithm Based on Region of Interest Extraction and Double Filter

Methods: First, in order to reduce environmental interference, the input image is preprocessed to enhance the main color of each logo. Secondly, in order to improve the extraction ability of Regions Of Interest, a Region Of Interest (ROI) detector based on Maximally Stable Extremal Regions (MSER) and Wave Equation (WE) is used, and candidate regions are selected through the ROI detector. Then, an effective HOG (Histogram of Oriented Gradient) descriptor is introduced as the detection feature of traffic signs, and SVM (Support Vector Machine) is used to classify them into traffic signs or background. Finally, the context-aware filter and the traffic light filter are used to further identify the false traffic signs and improve the detection accuracy. In the GTSDB database, three kinds of traffic signs, which are indicative, prohibited and dangerous, are tested. Objective: In order to solve the current traffic sign detection problem due to the interference of various complex factors, as it is difficult to effectively carry out the correct detection of traffic signs, a traffic sign detection algorithm based on the region of interest extraction and double filter is designed. Results: The results show that the proposed algorithm has a higher detection accuracy and robustness compared with the current traffic sign recognition technology.

A New Quasi Open Loop Synchronization Technique for Grid-Connected Applications

Abstract This paper presents an effective quasi open-loop (QOLS) synchronization technique for grid -connected power converters that is organized in two different blocks. The first block is a new flexible technique for extracting the positive and negative sequence voltage under unbalanced and distorted conditions. It is a decoupled double self-tuning filter (DD-STF) or multiple self-tuning filters (M-STF) according to the conditions. The main advantages of this technique are its simple structure and the fact of being able to work under highly distorted conditions. Each harmonic is separately treated and this allows for selective compensation in active filter applications. The second block is the frequency detector; we propose a neural approach based on an ADALINE for online adaptation of the cut-off frequency of the DD-STF and M-STF considering a possible variation in the main frequency. The main advantage of this method is its immunity to the voltage signal amplitude and phase. In order to improve the performance of the frequency estimation under distorted source voltage, a pre-filtering stage is introduced. Experimental tests validate the proposed method and illustrate all its interesting features. Results show high performance and robustness of the method under low voltage ride through.

Estimating PEMFC ohmic internal impedance based on indirect measurements

AbstractIn this study, the ohmic internal impedance of a proton exchange membrane fuel cell (PEMFC) is explored. A double Kalman filter (DKF) method is proposed to estimate the internal ohmic impedance based on the monitor output current density and voltage when the fuel cell is operated in the ohmic polarization region. First, the working current density is set between 0.4 and 1 A cm−2 by carrying out an initial experiment to obtain the PEMFC polarization curve. The PEMFC is assumed to be an equivalent circuit when the output current density is set in this range. Second, an experiment is also performed within the custom‐built platform based on the DKF algorithm. Monitoring data are obtained by Hall sensors in the direct current (DC) converter, and the stack ohmic resistance is calculated by the designed PEMFC internal resistance algorithm. Finally, verification is accomplished by comparing the simulated voltage based on the ohmic resistance with the experimentally measured output voltage using MATLAB/Simulink. The feasibility of this method to estimate the ohmic resistance is demonstrated. The ohmic internal resistance of the PEMFC is obtained in real time by the designed algorithm. Furthermore, the results indicate that moisture in the proton exchange membrane (PEM) can be reflected by the internal ohmic resistance of the PEMFC. The moisture can be adjusted based on this estimated impedance.

The Association between Vitamin D Deficiency and Chronic Tonsillitis in Children: an Evidence Based Case Report

A B S T R A C TBackground: vitamin D has an important influence on the host’s immune system bymodulating both innate and adaptive immunity and regulating the inflammatorycascade. Vitamin D deficiency may be related with reduced immunomodulation,specifically in preventing the occurrence of chronic tonsillitis. Objective: to identify theassociation between vitamin D deficiency with chronic tonsillitis in pediatric patients.Methods: the search was conducted with advanced searching on PubMed® andCochrane® according to the clinical question. The screening of title and abstract usinginclusion and exclusion criteria, double filter, and reading full text led to six usefularticles. The selected studies were critically appraised for validity, importance, andapplicability. Results: three original articles were eligible for this evidence-based casereport. All studies were considered to have good validity. All three studies reported anincreased risk of chronic tonsillitis with the vitamin D deficiency and/or insufficiency.Conclusion: Vitamin D deficiency may be associated with the increased risk of chronicor recurrent tonsillitis in children.