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Radars, due to their robustness to adverse weather conditions and ability to measure object motions, have served in autonomous driving and intelligent agents for years. However, Radar-based perception suffers from its unintuitive sensing data, which lack of semantic and structural information of scenes. To tackle this problem, camera and Radar sensor fusion has been investigated as a trending strategy with low cost, high reliability and strong maintenance. While most recent works explore how to explore Radar point clouds and images, rich contextual information within Radar observation are discarded. In this paper, we propose a hybrid point-wise Radar-Optical fusion approach for object detection in autonomous driving scenarios. The framework benefits from dense contextual information from both the range-doppler spectrum and images which are integrated to learn a multi-modal feature representation. Furthermore, we propose a novel local coordinate formulation, tackling the object detection task in an object-centric coordinate. Extensive results show that with the information gained from optical images, we could achieve leading performance in object detection (97.69\% recall) compared to recent state-of-the-art methods FFT-RadNet (82.86\% recall). Ablation studies verify the key design choices and practicability of our approach given machine generated imperfect detections. The code will be available at https://github.com/LiuLiu-55/ROFusion.

Shebin Hong,1– 3,* Weidong Jiang,1– 3,* Qinfeng Ding,1– 3,* Kaili Lin,1– 3 Cancan Zhao,1– 3 Xudong Wang1– 3 1Department of Oral & Cranio-Maxillofacial Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 2College of Stomatology, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 3National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xudong Wang; Cancan Zhao, Department of Oral and Cranio-Maxillofacial Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University, No. 639, Zhizaoju Road, Shanghai, 200011, People’s Republic of China, Tel +86-21-23271699, Fax +86-21-63136856, Email wang70@hotmail.com; cc.zhao@sjtu.edu.cnAbstract: Recently, programmable assembly technologies have enabled the application of DNA in the creation of new nanomaterials with unprecedented functionality. One of the most common DNA nanostructures is the tetrahedral DNA nanostructure (TDN), which has attracted great interest worldwide due to its high stability, simple assembly procedure, high predictability, perfect programmability, and excellent biocompatibility. The unique spatial structure of TDN allows it to penetrate cell membranes in abundance and regulate cellular biological properties as a natural genetic material. Previous studies have demonstrated that TDNs can regulate various cellular biological properties, including promoting cells proliferation, migration and differentiation, inhibiting cells apoptosis, as well as possessing anti-inflammation and immunomodulatory capabilities. Furthermore, functional molecules can be easily modified at the vertices of DNA tetrahedron, DNA double helix structure, DNA tetrahedral arms or DNA tetrahedral cage structure, enabling TDN to be used as a nanocarrier for a variety of biological applications, including targeted therapies, molecular diagnosis, biosensing, antibacterial treatment, antitumor strategies, and tissue regeneration. In this review, we mainly focus on the current progress of TDN-based nanomaterials for antimicrobial applications, bone and cartilage tissue repair and regeneration. The synthesis and characterization of TDN, as well as the biological merits are introduced. In addition, the challenges and prospects of TDN-based nanomaterials are also discussed.Graphical Abstract: Keywords: tetrahedral DNA nanostructure, carriers, antibacterial treatment, bone regeneration, cartilage regeneration

The stress-strain relationship in shales is generally time-dependent. This concerns their long-term deformation in unconventional reservoirs, and its influence on the in situ stress state therein. This paper presents an experimental investigation on the time-dependent deformation of the Longmaxi shale gas shale. A series of creep experiments subject the shale samples to long-term, multi-step triaxial compression. It is found that the shale samples exhibit varying degrees of time-dependent deformation, which can be adequately described by a power-law function of time. The experimental results establish the relationship between the elastic Young’s modulus and viscoplastic constitutive parameters, which are different from previous those derived from North American shales. Based on this viscoplastic constitutive model, the stress relaxation and the differential stress accumulation over geologic time scales can be estimated. It is found that linear elasticity substantially overestimates the differential stress accumulation predicted in the context of viscoplastic relaxation. The characterized viscoplasticity and stress relaxation are of vital importance for various geomechanical problems in shale reservoirs., Frontiers in Earth Science, 10, ISSN:2296-6463

Machine learning and deep learning classification models are data-driven, and the model and the data jointly determine their classification performance. It is biased to evaluate the model's performance only based on the classifier accuracy while ignoring the data separability. Sometimes, the model exhibits excellent accuracy, which might be attributed to its testing on highly separable data. Most of the current studies on data separability measures are defined based on the distance between sample points, but this has been demonstrated to fail in several circumstances. In this paper, we propose a new separability measure--the rate of separability (RS), which is based on the data coding rate. We validate its effectiveness as a supplement to the separability measure by comparing it to four other distance-based measures on synthetic datasets. Then, we demonstrate the positive correlation between the proposed measure and recognition accuracy in a multi-task scenario constructed from a real dataset. Finally, we discuss the methods for evaluating the classification performance of machine learning and deep learning models considering data separability.

Flax (Linum usitatissimum L.) is an important industrial crop in fiber production. This study is aimed to isolate specific germplazms with high potassium efficiency. Totally 50 flax germplazms were...

Flax stem bast fiber, a natural raw material used to make textiles, possesses poor heat and dye resistance, excessive stiffness and low elasticity. To improve fiber quality and quantity, flax fiber...

Supplemental material, sj-docx-1-scm-10.1177_00369330221132158 for Lasso algorithm and support vector machine strategy to screen pulmonary arterial hypertension gene diagnostic markers by Chenyang Jiang and Weidong Jiang in Scottish Medical Journal

Supplemental material, sj-docx-2-scm-10.1177_00369330221132158 for Lasso algorithm and support vector machine strategy to screen pulmonary arterial hypertension gene diagnostic markers by Chenyang Jiang and Weidong Jiang in Scottish Medical Journal

Supplemental material, sj-docx-1-scm-10.1177_00369330221132158 for Lasso algorithm and support vector machine strategy to screen pulmonary arterial hypertension gene diagnostic markers by Chenyang Jiang and Weidong Jiang in Scottish Medical Journal

In order to improve the ability of cognitive radar (CR) to adapt to the environment, the required ambiguity function (AF) can be synthesized by designing the waveform. The key to this problem is how to minimize the interference power. Suppressing the interference power is equivalent to minimize the expectation of slow-time ambiguity function (STAF) over range-Doppler bins. From a technical point of view, this is actually an optimization problem of a non-convex quartic function with constant modulus constraints (CMC). In this paper, we proposed a novel method to design a waveform to synthesize the STAF based on suppressing the interference power. We put forward an iterative algorithm within an alternating direction penalty method (ADPM) framework. In each iteration, this problem is split into two sub-problems by introducing auxiliary variables. In the first sub-problem, we solved the convex problem directly with a closed-form solution, then utilized the Riemannian trust region (RTR) algorithm in the second sub-problem. Simulation results demonstrate that the proposed algorithm outperforms other advanced algorithms in the aspects of STAF, range-cut and signal-to-interference-ratio (SIR) value.

In this paper, the history of flax breeding, the types, research methods, occurrence, and genetic mechanism of apomixis were reviewed. The development and genetic mechanism of apomixis in polyembryonic flax, the progress in inducing methods and other aspects was discussed by cytology, embryology, genetics, and molecular biology, etc., methods in this paper. The purpose of this study was to reveal the rules of apomixis and to improve the utilization efficiency of apomixis in breeding. The problems existing in apomixis breeding of polyembryonic flax and the research direction of apomixis of flax were put forward.

This paper briefly reviews virtual space vector pulse width modulation (VSVPWM) for the diode-clamped multilevel inverter (DCMLI). Based on the universal modulation model of the DCMLI with N-level, a modulation strategy named as full range capacitor voltage balance PWM (FRCVBPWM) is proposed, which has similar capacitor voltage balance characteristics as VSVPWM. The characteristic of FRCVBPWM is that there are respectively zero, N &minus, 1 and N &minus, 2 switching actions for the three phases of the DCMLI. Therefore, the total switching actions are greatly decreased compared with VSVPWM. The switching loss comparison between FRCVBPWM and VSVPWM is conducted by comprehensive simulations. Finally, the feasibility and superiority of FRCVBPWM over VSVPWM is verified by experiments.

Актуальность. По сравнению с традиционными месторождениями нефти, на морских месторождениях с тяжелой нефтью существует много проблем, связанных с низкой нефтеотдачей заводнения. Если бы мы обладали более глубокими знаниями о фильтрационных характеристиках водной и нефтяной фаз, это было бы очень полезно для улучшения состояния нефтеотдачи заводнения пласта с тяжелой нефтью. Цель: изучение закономерностей изменения фильтрационных характеристик водной и нефтяной фаз в морском месторождении с тяжелой нефтью, которые очень важны для решения задач разработки нефтяных месторождений и могут представлять руководство для создания моделей численного моделирования. Методы. Были учтены геологические характеристики пласта, флюидные свойства и технология строительства морского нефтяного месторождения Бохай с тяжелой нефтью. Влияние проницаемости керна, вымывания воды и вязкости нефти на кривую относительной проницаемости и эффективность вытеснения нефти заводнения было исследовано по методу нестационарного состояния. Изменение внутренней структуры керна представлено с помощью компьютерной томографии и ртутного теста давления. Результаты. С увеличением проницаемости керна относительная проницаемость водной фазы увеличивается, объем охвата водной фазы становится больше, поток двухфазного флюида становится шире и конечная нефтеотдача пластов увеличивается. Функция "очистки" и "эрозии", которая образуется от вымывания водой, оказывает влияние на структуру пор керна, увеличивает радиус порового канала керна и проницаемость керна, и ее влияние - на кривую относительной проницаемости и эффективность вытеснения нефти такое же, как влияние на увеличение проницаемости. С увеличением вязкости нефти способность регулирования подвижности воды ослабевает в процессе заводнения, объем охвата вытесняемой водной фазы уменьшается, сужается диапазон двухфазного потока, а конечная нефтеотдача уменьшается. The relevance. Compared with conventional reservoir, offshore heavy oil reservoir faced the problem of lower water flooding recovery. It is helpful to improve the water flooding recovery of heavy oil reservoir if we have more knowledge about seepage characteristics of water and oil. The main aim of the research is to investigate the change rule of seepage characteristics of water phase and oil phase in offshore heavy oil reservoir, which is helpful to the decision of field construction and can provide guidance for numerical simulation. Methods. The reservoir geological characteristics, fluid properties and field construction technology of the destination offshore heavy oil reservoir in Bohai Oilfield were taken into consideration. The impact of core permeability, injection water washout and crude oil viscosity on relative permeability curve and displacement efficiency of water flooding were studied, through core displacement experiment using displacement method of unsteady state. The change of core inside structure is presented by core CT scanning and mercury pressure test. Results. With the increase of core permeability, water phase relative permeability increases, the swept volume of water phase becomes bigger, two-phase flow span gets wider, and ultimate recovery enhances. The function of "cleaning" and "erosion" that water washout exerts on core pore structure would enlarge the pore throat radius, increasing core permeability, and its influence on relative permeability curve and displacement efficiency is the same as the influence of permeability increase. With the crude oil viscosity increasing, mobility control ability of water gets weaker in the process of water flooding, displacement phase viscous fingering phenomenon aggravates, the swept volume of water phase becomes smaller, two-phase flow span gets narrower, and ultimate recovery decreases.

The long noncoding RNA(lncRNA) small nucleolar RNA host gene 3(SNHG3) has been reported to be upregulated in colorectal cancer (CRC). However, its biological role and underlying mechanisms in CRC have not been well studied. The expression levels of SNHG3 were measured in CRC tissues and cell lines by real time quantitative PCR. Functional assays, including the cell counting Kit-8, wound healing and transwell invasion assays, were used to determine the effect of SNHG3 on CRC cell proliferation, migration and invasion,respectively. Furthermore, bioinformatics analysis, dual-Luciferase reporter assays and RNA immunoprecipitation were applied to determine the mechanism of SNHG3 in CRC. Mice xenograft models were established to assess the role of SNHG3 in CRC tumorigenicity and metastasis in vivo.The expression of SNHG3 was significantly upregulated in CRC tissues compared to adjacent normal tissues, which was positively correlated with advanced clinical stage, distant metastasis and poor overall survival. Functional experiments revealed that SNHG3 knockdown significantly decreased CRC growth and metastasis both in vitro and in vivo. Mechanistically, SNHG3 could bind to miR-539, thereby up-regulating the expression of its target gene runt-related transcription factor 2 (RUNX2), and play an oncogenic role in CRC progression. Our works suggest that lncRNA SNHG3 promotes CRC growth and metastasis via regulating miR-539/RUNX2 axis, suggesting that the SNHG3 might be a potential therapeutic target for CRC.

In this paper, carrier-based pulse width modulation (CBPWM), space vector PWM (SVPWM) and reduced switching losses PWM (RSLPWM) for the three-level neutral point clamped (NPC) inverter are introduced. In the case of the neutral point (NP) potential (NPP) offset, an asymmetric disposition PWM (ASPDPWM) strategy is proposed, which can output PWM sequences correctly and suppress the lower order harmonics of the inverter effectively. An NPP balance strategy based on carrier based PWM (CBPWM) is analyzed. A hybrid modulation strategy combining RSLPWM and the NPP balance based on CBPWM is proposed, and hysteresis control is adopted to switch between the two modulation strategies. An experimental prototype of the three-level NPC inverter is built. The effectiveness of the hybrid modulation is verified with a resistance-inductance load and a permanent magnetic synchronous motor (PMSM) load, respectively. The experimental results show that reduced switching losses and an acceptable NPP can be effectively achieved in the hybrid modulation strategy.

Strain sensing is one of the core parts of smart fabric which can be expressed by electrical signals affected by external forces. In this paper, the strain sensing functional fabric was prepared by using the acidified carbon nanotubes (a-CNTs) as the conductive layer and the waterborne polyurethane (WPU) as the adhesive based on foam finishing method. The results showed that many hydroxyl and carboxyl groups were introduced into the surface of CNTs through acidification, which improved their dispersibility in aqueous solution. The blended film of a-CNTs and anionic WPU had excellent conductive properties. When the ratio of a-CNT to WPU was 9:1, the fabric had the smallest resistivity, about 0.13 Ω⋅m, and the corresponding tensile sensing sensitivity up to 55.2.

Neutrophil extracellular traps (NETs) are shown to play important roles in the progression or development of systemic autoimmune diseases. However, implication of NETs or NETosis in the pathogenesis of non-systemic autoimmune diseases such as Hashimoto's thyroiditis (HT), a chronic inflammatory organ-specific autoimmune disease, has not been previously reported. In the present study, our results demonstrate that the concentration of NET products, neutrophil elastase (NE) and proteinase 3 (PR3) in plasma, are significantly higher in the patients with HT than in healthy controls, respectively. In addition, PR3 concentration in plasma was positively associated with the titers of autoantibodies against thyroglobulin (TGAb) and thyroid peroxidase (TPOAb) in serum, respectively. Consistently, NETosis was more markedly induced in neutrophils derived from the HT patients than controls. Concomitantly, IL-6 production in the NETosis induction system in the neutrophils from the patients was significantly higher than those in controls. Moreover, serum from HT patients but not healthy controls induced more pronounced NETosis in neutrophils. Meanwhile, our immuno-fluorescence staining results showed that NETs from the HT patients contained autoantigens. These findings together indicate roles for NETs and/or NETosis in autoantibody generation as well as pathogenesis of HT. Therefore, the underlying mechanisms of NETs in the pathogenesis of HT warrant further study.

As the grid-connected converter is operating in the unbalanced three-phase grid in the traditional control strategies, the even harmonics of the voltage appear in DC-link and the odd harmonics of the current in AC-link, which will severely affect the performance of the grid-connected converter. Under this circumstance, the unbalanced three-phase grid will bring various negative effects and difficulty to the control of the converter, such as the fluctuation of active and reactive powers, non-sinusoidal and unsymmetrical three-phase currents. First, this study analyses the form of the fluctuation of power based on the instantaneous power theory and establishes a mathematical model of a grid-connected converter under unbalanced grid voltage. And then, a more complete description of the control problem of the converter is given, after three different control objectives, the fluctuation of active/reactive power and the non-sinusoidal and unsymmetrical grid currents, are considered at the same time. A novel method of separating the instantaneous positive and negative sequence components is proposed and well applied during achieving the different control objectives. Finally, the experimental results are compared, showing that the strategy is effective.

Multilevel voltage source inverters are most promising when employed in high-power and high-voltage applications. As the number of inverter levels increases, the algorithm of space-vector pulse-width modulation (SVPWM) becomes increasingly complex. Based on the intrinsic relationship between SVPWM algorithms for 2-level inverters and those for arbitrary-level inverters, here a novel SVPWM algorithm is proposed for an arbitrary-level inverter. Considering that the nearest three vectors are used to synthesise the reference vector, the on-time of the voltage vector for an arbitrary-level inverter can be acquired from that for a 2-level inverter via the use of a linear transformation. This algorithm is verified through simulation and experiments, with the latter proving that the proposed algorithm can meet the real-time requirements of multilevel inverters.

The hydraulic jet radial drilling technology is a low-cost production and completion technology for effectively developing low-permeability marginal reservoirs, thin-bed reservoirs with edge and bottom water, and depleted oil and gas fields. It has been successfully and widely applied in sandstone, coalbed methane, and heavy oil reservoirs. In order to explore its application in carbonate reservoirs, specially economically and efficiently develop low-permeability thin-layer carbonate reservoirs, the pilot of hydraulic jet radial drilling technology in the carbonate reservoir application was successfully completed through the research on the principle, advantage, existing problems and application condition of radial jet drilling, economic productivity was got, and cost-effective development was achieved, this pilot provided a method for the development of low permeability thin layer carbonate reservoir. This research shows that the hydraulic jet radial drilling technology has its unique technical advantages, which can enable some reservoirs to increase production or injection, but it is not suitable for every well, it has certain applicable conditions, such as the depth, thickness, and temperature of the target zone, and the conditions of well inclination, casing and wellbore have certain requirements too. The hydraulic jet radial drilling technology can achieve the expected target based on the zone and well selection, in selecting layers, as far as possible, homogeneous oil layers with good reservoir physical properties should be selected; the key of its successful implementation is the depth and azimuth control, wellbore diameter and operation safety control. The application of hydraulic jet radial drilling in carbonate reservoirs will make the spray hose wear large due to its high Young's modulus the high hardness, which affects the treatment footage; the use of acid in jet drilling can increase the radial drilling footage, but on the other hand can also produce impurities affecting the operation. The working fluid for jetting must meet the requirements of no solid phase.

Increasing environmental pollution caused by the volatile organic compounds because of their toxicity is a matter of great concern; thus, it is crucial to develop processes that can destroy these compounds effectively. It has been found that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene in a batch reactor can be greatly enhanced by loading TiO2 on the surface of Ce0.67Zr0.33O2. In this work, we have investigated the loading amount of TiO2 on Ce0.67Zr0.33O2 in enhancing the photocatalytic activity of TiO2. This article reveals that the optimal loading amount of TiO2 on Ce0.67Zr0.33O2 for the degradation of gaseous benzene is 1% (wt). The prepared photocatalyst was characterized by Brunauer-Emmet Teller, X-ray diffraction, UV–vis diffuse reflectance, and X-ray photoelectron spectroscopy. The deposited titania was well dispersed in the Ce0.67Zr0.33O2 matrix. TiO2/Ce0.67Zr0.33O2 absorbs much more ultraviolet light than TiO2 in the ultraviolet light region. The binding energy values of Ti2p shift to lower value. TiO2/Ce0.67Zr0.33O2 demonstrates 1.5 times photocatalytic activity of that of pure TiO2. Based upon these observations, the mechanistic role of Ce0.67Zr0.33O2 in the photocatalytic oxidation reaction has been suggested. The suggested mechanism is electrons transfer, increase of the surface coverage of active oxygen species, and increase of the absorption from 210 to 400 nm of TiO2/Ce0.67Zr0.33O2. © 2009 American Institute of Chemical Engineers Environ Prog, 2009

The Triassic reservoir in the Jinan area of Tarim Oilfield consists largely of interbedded sand and shale. Because of the large overlap between sandstone and shale impedance, it is difficult to distinguish sandstone from shale by acoustic impedance alone. Compared to acoustic impedance, elastic impedance contains more lithologic and physical information of the reservoir. Based on meticulous well-tie calibration, elastic impedance data volumes for 10°, 20°, and 30° emergence angles are obtained using pre-stack elastic impedance inversion. A non-linear statistical relationship between elastic impedance and shale content is set up by a PNN neural network. The non-linear mapping relationship is used to predict the reservoir shale content from elastic impedance, which will depict and predict the reservoir oil-bearing sands.

Complex motions such a micro-motions induce complex range-Doppler coupling effect in radar imaging. Hence it is a challenge to reconstruct a clear range profile of a target with micro-motion. Stretch processing with fine motion compensation cannot perform well while it tics to eliminate the distortion of range profile caused by Doppler effect, because it is difficult to accurately estimate each scattering center velocity during coherent processing interval. Based on nonuniform stretch processing (NSP), a new technology is proposed to decouple range, time and Doppler and then achieve range profile of target with micro-motion. The new technology uses a new synthetic wide-band waveform and has an innovative mathematic interpretation. Statistical properties of the new approach are primarily examined. Typical models of target with micro-motion for high resolution rader are presented. Monte Carlo simulations demonstrate the performance of the new technology and the simulation result confirm our expecta...

The salinization and alkalization of soil are widespread environmental problems, and alkaline salt stress is more destructive than neutral salt stress. Therefore, understanding the mechanism of plant tolerance to saline–alkaline stress has become a major challenge. However, little attention has been paid to the mechanism of plant alkaline salt tolerance. In this study, gene expression profiling of flax was analyzed under alkaline-salt stress (AS2), neutral salt stress (NSS) and alkaline stress (AS) by digital gene expression. Three-week-old flax seedlings were placed in 25 mM Na 2 CO 3 (pH 11.6) (AS2), 50 mM NaCl (NSS) and NaOH (pH 11.6) (AS) for 18 h. There were 7736, 1566 and 454 differentially expressed genes in AS2, NSS and AS compared to CK, respectively. The GO category gene enrichment analysis revealed that photosynthesis was particularly affected in AS2, carbohydrate metabolism was particularly affected in NSS, and the response to biotic stimulus was particularly affected in AS. We also analyzed the expression pattern of five categories of genes including transcription factors, signaling transduction proteins, phytohormones, reactive oxygen species proteins and transporters under these three stresses. Some key regulatory gene families involved in abiotic stress, such as WRKY, MAPKKK, ABA, PrxR and ion channels, were differentially expressed. Compared with NSS and AS, AS2 triggered more differentially expressed genes and special pathways, indicating that the mechanism of AS2 was more complex than NSS and AS. To the best of our knowledge, this was the first transcriptome analysis of flax in response to saline–alkaline stress. These data indicate that common and diverse features of saline–alkaline stress provide novel insights into the molecular mechanisms of plant saline–alkaline tolerance and offer a number of candidate genes as potential markers of tolerance to saline–alkaline stress.

Hypertension is a major worldwide health issue for which only a small proportion of cases have a known mechanistic pathogenesis. Of the defined causes, none have been directly linked to heightened vasoconstrictor responsiveness, despite the fact that vasomotor tone in resistance vessels is a fundamental determinant of blood pressure. Here, we reported a previously undescribed role for smooth muscle hypoxia-inducible factor-1α (HIF-1α) in controlling blood pressure homeostasis. The lack of HIF-1α in smooth muscle caused hypertension in vivo and hyperresponsiveness of resistance vessels to angiotensin II stimulation ex vivo. These data correlated with an increased expression of angiotensin II receptor type I in the vasculature. Specifically, we show that HIF-1α, through peroxisome proliferator-activated receptor-γ, reciprocally defined angiotensin II receptor type I levels in the vessel wall. Indeed, pharmacological blockade of angiotensin II receptor type I by telmisartan abolished the hypertensive phenotype in smooth muscle cell-HIF-1α-KO mice. These data revealed a determinant role of a smooth muscle HIF-1α/peroxisome proliferator-activated receptor-γ/angiotensin II receptor type I axis in controlling vasomotor responsiveness and highlighted an important pathway, the alterations of which may be critical in a variety of hypertensive-based clinical settings.

This paper presents an improved further treatment technical process for polymer-containing waste water in the oilfield. The core equipment of the system is a forced filtration unit, which uses walnut shells as the main filtering material, avoiding such disadvantages of ordinary mechanical filtering materials as being easy to be contaminated and difficult to be cleaned. It is equipped with an automatic backwash unit, which may timely and thoroughly back wash and prevent the filtering material from hardening and the quality of effluent water from deteriorating, etc. Compared to application of scrubbing pump at outside of the body, it may save a large amount of cost. After optimizing the backwash parameters by using the orthogonal experimental method, the backwash cycle is extended by 15%, the backwash intensity is decreased by 28.6%, the backwash time is saved by 40%, water is saved by 46.8%, and the electricity is saved by 23.44%.Experiments and field tests indicate that the after-filtration water quality is assured. It can improve the work efficiency, extend the service life of the filtering material, reduce the overflow risks as a result of a large amount of backwash water, effectively save resources, and deliver good economic and social benefits.

The real sea-clutter data are always hard to analyze due to their instinct complexity, large scale non-stationary, and lack of fundamental understanding of the natural dynamics. Measurable modeling of sea clutter is an important precondition in many research areas and practical applications, such as salvage and marine radar signal processing. However, few works have been down on the time-frequency analysis of sea clutter, especially no effective method for sea state inversion from sea clutter has been proposed. In this work, the author take into account the motion model of sea surface in typical scenarios via time-frequency and micro-Doppler effect analysis. Different contributions of the waves' velocity may provide intuitionistic ISAR images and contain certain motion parameters, from which certain sea state parameters might be inversed. Both theoretical simulation and experimental results indicate the usefulness of the model and method proposed in this work.

The undergraduate accounting education, an important component of accounting education, has undertaken the essential missions that cultivate all levels of society-needed accountants based on market-oriented culture. The demands for accounting personnel in practice circle have shift from just focusing on accounting knowledge to concentrating professional ethics, practical ability, interpersonal communication and other vocational skills. Through analyzing and researching the current status of undergraduate education, this paper gives some proposals and measures, such as strengthening professional ethics education, improving interpersonal skills, and enhancing professional practices.

Precession is a key feature for distinguishing warhead from decoys in the missile mid course, and a method of feature extraction of target with precession based on the micro-Doppler modulation is provided in this paper. The radar echo model of cone with precession is simulated by point scattering model, and the modulation of Doppler frequency caused by precession is developed. As the spread of echo spectrum corresponding to the modulation amplitude of micro-Doppler frequency, a method utilizing the spread of echo spectrum is provided to estimate the precession angle. Based on the characteristics of micro-Doppler, a 2D reconstruction of the target using inverse Radon transform and time-frequency distribution is proposed. The experiments demonstrate the validation of proposed method.