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In order to improve the prediction accuracy of the theoretical model on steel corrosion degree, the multiple correction coefficient method was used to establish a piecewise constitutive model based...

Context Despite the abundance of knowledge regarding high-altitude pulmonary edoema (HAPE) and high-altitude pulmonary hypertension (HAPH), their prevalence continues to be on the rise. Thus, there is an urgent need for newer safe, effective, and relatively economic drug candidates. China is particularly known for the use of medicinal plants. Objective This review summarizes the medicinal plants used for HAPE and HAPH in the past 30 years, as well as some potential plants. Methods Publications on HAPE and HAPH from 1990 to 2020 were identified using Web of Science, PubMed, SCOPUS, Springer Link, Google Scholar databases, Chinese Clinical Trial Registry and CNKI with the following keywords: ‘medicinal plants,’ ‘hypoxia,’ ‘high altitude pulmonary edema,’ ‘high altitude pulmonary hypertension,’ ‘pathophysiology,’ ‘mechanisms,’ ‘prevention,’ ‘treatment,’ ‘human,’ ‘clinical,’ ‘safety,’ and ‘pharmacokinetics.’ Results We found 26 species (from 20 families) out of 5000 plants which are used for HAPE and HAPH prevention or treatment. Rhodiola rosea Linn. (Crassulaceae) is the most widely utilized. The most involved family is Lamiaceae, which contains 5 species. Discussion and Conclusions We mainly reviewed the medicinal plants and mechanisms for the treatment of HAPE and HAPH, and we also assessed related toxicology experiments, pharmacokinetics and bioavailability. Potential medicinal plants were also identified. Further research is needed to determine the pharmacological effects and active ingredients of these potential medicinal plants.

Summary Diabetic cardiomyopathy (DCM) is one of the most common complications of diabetes without effective treatment options. Its pathogenesis is complex and remains unclear. Long non-coding RNA (lncRNA) MIAT allele has been reported to be enriched in DCM patients and activate a pyroptosis program in hypoxia-induced H9c2 cells. Thus, whether MIAT played a role in DCM pyroptosis remains to be clarified. In the study, the expression of MIAT was found elevated in the serum of diabetic patients, as well as in high-glucose induced cardiomyocytes and diabetic mice. Further, the expression levels of CASP1 and pyroptosis correlation factors (IL-1 and IL-18) were downregulated after silencing MIAT. Through modeling and validation experiments, we then confirmed that the MIAT-miR-214-3p-CASP1 axis serves as an essential point in pyroptosis of DCM mice. These results suggested that silencing MIAT would be a potential treatment strategy for DCM., Graphical abstract, Highlights • MIAT and caspase-1 were overexpressed in serum and cardiomyocytes of diabetic patients • High glucose caused inflammatory damage and calcium overloaded in cardiomyocytes • MIAT regulated pyroptosis in cardiomyocytes via MIAT-miR-214-3p-CASP1 axis, Classification Description: Physiology; Cellular physiology; Molecular biology

This work is to introduce a new model for fatigue life prediction. At first, considering the weakening speed of weight function in the stress field of intensity method is too fast, a modification is presented to make it more suitable for the calculation of the fatigue life of the key components. In this model the stress contour line was proposed as the boundary of the damage zone and a new mathematical model for stress gradient was constructed. Then, the determination of the damage zone and the direction angle were given. Numerical simulations were performed to analyze the proposed new method. On the basis of the new stress field of intensity method, two examples were analyzed and calculated. Compared with the traditional method, the damage zone determined by the improved stress field method can change with the load amplitude, and it is closer to the shape and size of the real damage zone. The experiment effectively verifies the rationality of the new mathematical model and the feasibility of this new approach. With the small error and good stability, this new approach can be well used in the fatigue life prediction of notched specimen.

A large number of charging piles installed on roadside parking spaces and smart poles on the roadside of the Internet have become essential substation infrastructure (roadside) for building a vehicle-road coordinated charging network for electric vehicles. The management system of China National Grid's network-load interaction includes the interaction between these main stations (traffic control stations) and substations (roadsides). The Internet-friendly interactive communication protocol for China's vehicle-road coordination is IEC 60870-5-104 (104 protocol). The control network of the vehicle-road collaborative charging network has many characteristics, such as multiple levels, multiple types, and frequent information exchange for monitoring and control. Various types of operational information and control commands are subject to eavesdropping, tampering, and interruption during collection, transmission, and triggering. This paper proposes a command-level anomaly detection (CAD) method for a vehicle-road collaborative charging network. The CAD method analyzes the protocol for the specification format and business command characteristics of the 104 protocol. This paper uses the dynamic analysis protocol fuzzy test to realize the dynamic information in the program to guide the generation of test cases and pass the Markov state transition diagram. We describe the state transition and abnormality identification of protocol messages. We also design a long-term memory network to implement instruction-level anomaly feature mining. The experiment proved the validity of CAD. If we adopt other new protocols for the vehicle-road coordinated network in different countries or regions, the analysis of the new protocol can be completed in the same way, which has strong application value and prospect.

The presence vertebral artery (VA) abnormalities in the upper cervical may be a potential cause of catastrophic complication in the posterior approach of the upper cervical spine surgery. The aim of this study was to demonstrate the real incidence of the V3 segment anomaly in patients who need upper cervical surgery, and tried to find out the risk factors of V3 segment anomaly to evaluate the necessary of computed tomographic angiography (CTA) for upper cervical surgery. This systematic review was conducted following the preferred reporting items for systematic reviews and meta-Analyses (PRISMA). Retrospective studies and reports of case series involving human subjects with data on anomalies of vertebral artery in upper cervical spine were included. Data on the prevalence of persistent first intersegmental artery (PIA), fenestration of the VA (FA), posterior inferior cerebellar artery (PICA) were extracted. A total of 16 articles involving 5927 subjects met the inclusion criteria. The total incidence of V3 segment anomaly in the patients with bony abnormalities was 25.9% (74/286): PIA was 17.5%, FA was 6.6% and PICA was 1.8%. The total incidence of V3 segment anomaly in the patients without bony abnormalities was 2.7% (152/5671): PIA was 1.76%, FA was 0.4% and PICA was 0.5%. The total incidence of V3 segment anomaly in Asian population without bony abnormalities was 5.8%, while in European and American population was 0.8 and 0.6%, respectively. Patients with bone abnormalities are high risk factor for VA abnormalities, CTA is of paramount importance to evaluate the variant VA anatomy. However, regarding to the low incidence of V3 variation in normal population, we do not recommend preoperative CT angiography as mandatory part of preoperative.

Metastasis is the leading cause of cancer-related death. Surgery is a common intervention for most primary solid tumors; however, surgical trauma-related systemic inflammation facilitates distant tumor metastasis by increasing the spread and adhesion of tumor cells to vascular endothelial cells. Currently, there are no effective interventions to prevent distant metastasis. Here, we show that HECTD3 deficiency in vascular endothelial cells (ECs) significantly reduces tumor metastasis in tumor resection metastasis, LPS-induced metastasis and MMTV-Neu metastasis models. HECTD3 depletion downregulates expression of adhesion molecules, such as VCAM-1, ICAM-1 and E-selectin, in mouse primary ECs and in human primary umbilical vein ECs stimulated by inflammatory factors and inhibits adhesion of tumor cells to ECs both in vitro and in vivo. We demonstrate that HECTD3 promotes stabilization and kinase activity of IKKα by ubiquitinating IKKα with K27- and K63-linked polyubiquitin chains at K296, increasing phosphorylation of histone H3 at Ser10 to promote NF-κB target gene transcription. IKKα kinase inhibitors prevented LPS-induced pulmonary metastasis. These findings reveal the promotional role of the HECTD3-IKKα axis in tumor hematogenous metastasis and provide a potential strategy for tumor metastasis prevention.

After the outbreak of the new coronavirus pneumonia, it has been broadcasting soon. Medical supplies are out of used. Chinese people have provided medical supplies and raised donations to help Hubei Province, China. While, Red Cross Society of Hubei Branch and Wuhan Branch were suspected for unfair distribution of donated materials, the backlog of donated items, and inefficient assignment. These problems exposed public welfare organizations to the public sights. For information sharing, Jiangsu Province developed a new COVID-19 Donation Management Blockchain System (CDMBS). The system improves the transparency and credibility of donation information with the blockchain. Based on the overall architecture of Jiangsu's new coronavirus charity donation management blockchain, this paper designs various types of security control components. The components include the middleware for secure connection to protect the user certificate security. We designed CA certificate user management middleware to realize more secure registration and query functions for users with extended attributes. There is also a blockchain query middle with access control Software to ensure that important blockchain information is viewed securely. Experiments have verified the effectiveness and applicability of these security control components. It can be applied into a variety of scenarios in the CDMBS.

Pedestrian attribute recognition aims to accurately identify attributes from pedestrian images. Visually similar pedestrian images tend to share similar attributes, and the upper and lower clothing attributes normally match in style. However, how to effectively capture these relations remains a challenging topic. In this paper, we propose a novel network Pentadent-Net (PD-Net). The network consists of a “Representation Refining Branch (RRB)” and an “Attribute Fusion Branch (AFB)”. The RRB reduces the feature distances among visually similar images, and the AFB generates a joint-representation for each attribute based on its correlation with other attributes. The polished features from the two branches are then applied to capture the inter-sample relations and attribute dependencies respectively. We also further associate features from the two branches to enrich feature representations. Experimental results on two benchmark datasets (PETA and PA-100K) by our proposed approach demonstrate its advantages over state-of-the-art methods.

Background Cerebral ischemic stroke is a highly debilitating disease, in which inflammation is well document to play a pivotal role in its pathophysiology. Microglia are the the major immuncompetent cells of the brain involved in different neuropathologies. Recent discovery of cyclic GMP-AMP synthase(cGAS) activation and its induction of the downstream signaling protein stimulator of interferon genes (STING) is increasingly recognized as a crucial determinant of neuropathophysiology. Although cGAS-STING pathway has been reported to play an important role in inflammatory response in myocardial infarction (MI), its mechanism in inflammatory response in ischemic stroke (IS) has remained to be fully explored.Methods In light of the above, this study sought to explore the roles of cGAS-STING pathway in inflammatory reaction in IS. It is hoped that the results would provide new insights for designing of therapeutic strategies targeting at IS. We used HT22 cells to establish an oxygen-glucose deprivation (OGD) cell model. The supernatant derived from this and which contained OGD-induced DAMPs(OIDs) was used to stimulate the BV2 microglia. Additionally, we used siRNA technology to interfere with cGAS gene expression to observe changes in downstream cytokines. Furthermore, we established middle cerebral artery occlusion (MCAO) mouse model and performed cGAS-siRNA lentivirus infection to further elucidate the mechanism of cGAS-STING pathway in vivo.Results We show here that OIDs strongly activated the cGAS-STING pathway and triggered accumulation of a plethora of proinflammatory factors in activated Microglia. Of note, the cascade reaction was successfully inhibited by cGAS-siRNA. Furthermore, we extended the study of cGAS-STING in a mouse MCAO model, which showed that inhibiting cGAS-STING pathway can effectively diminish MIDs(MCAO-induced DAMPs)-induced neuronal apoptosis and ultimately functional improvement.Conclusion The present results have shown GAS-STING signaling pathway controls the polarity transformation of microglia. The underlying mechanisms of cGAS-STING triggering microglial inflammatory response is now better clarified which made the pathway a potential therapeutic target of IS.

Connectionist Temporal Classification (CTC) and attention mechanism are two main approaches used in recent scene text recognition works. Compared with attention-based methods, CTC decoder has a much shorter inference time, yet a lower accuracy. To design an efficient and effective model, we propose the guided training of CTC (GTC), where CTC model learns a better alignment and feature representations from a more powerful attentional guidance. With the benefit of guided training, CTC model achieves robust and accurate prediction for both regular and irregular scene text while maintaining a fast inference speed. Moreover, to further leverage the potential of CTC decoder, a graph convolutional network (GCN) is proposed to learn the local correlations of extracted features. Extensive experiments on standard benchmarks demonstrate that our end-to-end model achieves a new state-of-the-art for regular and irregular scene text recognition and needs 6 times shorter inference time than attentionbased methods., Accepted by AAAI 2020

Network selection in the Internet of Vehicles has become a popular topic of research. Unlike existing algorithms for heterogeneous network environments that rarely consider user satisfaction, in this paper, we propose a network selection strategy that takes into account both user satisfaction and transmission efficiency. We employ the effective capacity concept, which describes the maximum throughput a system can achieve under a specific statistical Quality-of-Service (QoS) delay violation probability constraint. This strategy first analyzes the influence of different utility function weight coefficients, transmission power, and time delay on each network utility satisfaction function. It is evident that the weight coefficient is proportional to the value of the utility function. Within a constrained transmission power range, the rate of increase of the function gradually slows down until it approaches a fixed value. When the delay factor value is larger, the function value is smaller, which indicates that the pursuit of lower delay will sacrifice other network performance aspects. In order to determine the maximum value of each network utility satisfaction function, a convex optimization theory is introduced for the joint optimization of user satisfaction and transmission efficiency. Finally, simulation experiments carried out under three representative network environments show that the proposed strategy is efficient and reliable.

The Yunnan power grid has a large-scale hydropower station, whereby the power generated at the station is transmitted via HVdc lines under an asynchronous operation mode. In the system performance test of the Yunnan asynchronous operation, a 0.05-Hz ultralow-frequency oscillation occurred in the grid. This ultralow-frequency oscillation is a frequency stability problem caused by instability of hydraulic turbine governing system, which is quite common in the islanded system and very rare in the normal synchronous system. The relationship between the speed governing system stability of one unit and that of the system with parallel operation units was proposed to explain that the high proportion of units with an unstable governing system will lead to system frequency instability and the reduction in loads in the traditional sense was proven to further worsen the frequency stability of the Yunnan asynchronous system. By using related measures, the ultralow-frequency oscillation of the Yunnan asynchronous system has been curbed effectively. System performance testing verified the effectiveness of the analysis and the measures.

Rescue of satellite with attitude fault is of great value. Satellite with improper injection attitude may lose contact with ground as the antenna points to the wrong direction, or encounter energy problems as solar arrays are not facing the sun. Improper uploaded command may set the attitude out of control, exemplified by Japanese Hitomi spacecraft. In engineering practice, traditional physical contact approaches have been applied, yet with a potential risk of collision and a lack of versatility since the mechanical systems are mission-specific. This paper puts forward a touchless attitude correction approach, in which three satellites are considered, one having constant dipole and two having magnetic coils to control attitude of the first. Particular correction configurations are designed and analyzed to maintain the target’s orbit during the attitude correction process. A reference coordinate system is introduced to simplify the control process and avoid the singular value problem of Euler angles. Based on the spherical triangle basic relations, the accurate varying geomagnetic field is considered in the attitude dynamic mode. Sliding mode control method is utilized to design the correction law. Finally, numerical simulation is conducted to verify the theoretical derivation. It can be safely concluded that the no-contact attitude correction approach for the satellite with uniaxial constant magnetic moment is feasible and potentially applicable to on-orbit operations.

This letter introduces a W-band full-polarization monopulse antenna based on the sequential rotate polarization theory. The proposed antenna consists of a main reflector, a subreflector, and a sequential rotate polarization feed to realize full-polarization monopulse angle measurement. The circular polarization monopulse patterns are simulated and measured by using special amplitude and phase setting. The measured results are in good agreement with the simulated ones. The SUM beam gain of the proposed antenna is 36.1 dBi by eliminating the loss of W-band comparator, cross-polarization level is better than −23 dB, and 3-dB beamwidth is 1.65°. The first sidelobe level is under −17 dB. The gain ratio between the SUM and DIFF beams is 5.5 dB. The proposed antenna is a good candidate for W-band full-polarization monopulse detector.

Crowdsourcing has already attracted a wide attention in the field of machine learning and its related fields. A large amount of labeled data can be obtained quickly and cheaply on crowdsourcing platforms. To deal with the problem that labels collected from crowds are usually noisy due to the low accuracy of non-expert online workers, we use quality control methods to improve the qualities of crowd data. Unfortunately, current quality control methods only consider the instance difficulty or the worker reliability to account for the variety of labels to the same instance, and these methods did not take subjectivity of workers into consideration which also effects the responses. In this paper, we present a novel subjectivity-aware algorithm for label aggregation, which also model the difficulty of instances and reliability of workers as latent parameters. This method is an EM-like algorithm, which not only infers the ground truth of the instances, but also simultaneously estimates the latent parameters. Experimental results on real-world datasets show that our method outperforms the state-of-the-art ground truth inference algorithms.

As a novel and potential supporting technology for on-orbit operation missions, spacecraft electromagnetic docking has not only distinct visible advantages, but also several intrinsic unconspicuous capabilities, such as the self-docking capability which could be exploited to alleviate the burden of the docking controller. Based on theoretical derivation and comparison with the near-field model and numerical simulation, the feasibility of utilizing the far-field electromagnetic force/torque model to spacecraft electromagnetic docking characteristics analysis is firstly verified. Then, the self-docking capability is studied with self-alignment and self-attraction analysis, and the necessary condition for the former and the sufficient condition for the latter are derived. Finally, a velocity-aimed electromagnetic docking control approach based on the self-docking capability and the conservation laws is put forward and verified by numerical simulations.

The falling film evaporation outside the elliptical tube was studied and compared with the circular tube for the design and improvement of seawater desalination system using the method of theoretical analysis, CFD numerical simulation and experiments. The experiment shows that the thickness of liquid film outside elliptical tube of E (ellipticity) = 1.5 obtained from the simulation agrees well with the experimental data and the maximum deviation is within 8%. This fully illustrates that the numerical model is correct and that analog calculation is feasible. The experimental results also manifested that heat transfer coefficient of the system with E = 1.5 elliptical tubes increases by 20–22% compared with circular tubes. This study testified that it is superiority and feasibility that elliptical tubes were applied to falling-film evaporation and seawater desalination of horizontal tubes. The exploratory researches will be conducted for promoting the design and application of falling film evaporation with elliptical tubes in the seawater desalination system.

Optical technology is widely applied in the China Lunar Exploration Program (CLEP) and the first China Martian exploration project: More than half of the scientific payloads were optical remote-sensing payload, and it was also widely used in the engineering areas including autonomous navigation, TT&C, monitoring, rendezvous and docking. In this paper, accomplished CLEP missions, on-going Chinese lunar and Martian projects and especially main achievements of optical technology applications were overviewed. Roadmap on China's future lunar, mars, jupiter and asteroids exploration was introduced. Development trends and prospects of optical technology in lunar and deep space exploration were analyzed and proposed.

This paper proposes a new process that assembly simulation with 3-D model which obtained from product to improve the reliability of spacecraft assembly. 3-D model of the satellite camera which obtained by reverse engineering was used in DELMIA virtual assembly simulation. The point cloud date of the model was scanned by laser radar, and the scanning accuracy is 0.3mm. To get more accurate model data, firstly it’s necessary to remove noise data by the method of HCI and curve inspect; then, min-distance method was used to streamline the point data, and repair the data by complementary surface; finally, reconstruct the model by the triangular Bezier surface. Because the model obtained by RE is more exact than the ordinary model, the virtual assembly simulation is more useful. During the period of installing the camera, as the simulation, the risk was avoided and the process was successful.

The uncertainties of renewable energy and load demand challenge the short-term operation of power system. Although robust unit commitment has been extensively studied, we propose a novel approach for day-ahead scheduling in multi-area power system, which is in compliance with the operation pattern of hierarchically-organized system operators such as in China. The problem is formulated as a two-stage robust optimization, in which the first-stage problem minimizes a quadratic function to decide an interval of daily generation, and the second-stage problem works out generation and transmission power profiles while guaranteeing the robust feasibility of the pre-decision with regard to any realization within the uncertainty set. Column-and-constraint generation method are adopted in the solution procedure. We carry out numeric experiment based on China Southern Grid, after which the performance of our algorithm is assessed, and the effectiveness and feasibility of the proposed approach are verified.

The function of the donor foot has been affected after using big toe wrap-around flap for thumb reconstruction. A modified operation method has been developed to reduce the adverse effect on the donor foot. The current study compared the long-term effect of the classic and the modified operation methods on the donor foot. Gait analysis was carried out, including how the patient walked, the walking speed and walking distance, and how the patient jumped and ran. Plantar pressure was measured while the patient was standing and moving. A total of 45 patients who received the 2 different operation methods were included. The follow-up time was 4-10 years with a mean of 6.5 years. Various degrees of complications occurred for the 21 patients who received the classic operation method. For these patients, plantar pressure of the donor foot was obviously different comparing with the healthy unaffected foot while the patient was standing or walking. For the 24 patients who received the modified operation method, no obvious complications were observed and the plantar pressure of the donor foot and the healthy unaffected foot was similar while the patient was standing or walking. In conclusion, both the classic and the modified operation methods have affected the function of the donor foot after using the big toe wrap-around flap for thumb reconstruction. However, the donor foot was less affected when the modified operation method was used.

A novel S-band antenna is proposed in this paper. The antenna consists of two layers of radiant dipole. The unit is capable of realizing broad beam-width of 144° in E-plane with isolation better than -35dB between two ports. The circular polarization can be achieved by exciting two ports with equal amplitude and 90° phase difference. Moreover, the axial ratio is less than 2dB in the antenna operating frequency band. At last, a triangular grid array with 64 elements is designed. The simulated results show that the designed array can meet the requirements of large scanning angle. It can be applied for the fifth generation mobile communications (5G) Multiple-Input Multiple-Output (MIMO)base station.

Most of the disabled spacecraft are spun, which are dangerous to other normal work spacecraft. Therefore, the disabled spacecraft need to be cleared and the first step is de-tumbling its angular velocity to an acceptable value. This paper investigates the dynamics and controller design of electromagnetic de-tumbling, analyzes the effects of the Earth's magnetic field, the inclination and the orbit height, and utilizes the ‘Two-to-One’ de-tumbling mode which eliminates the incidental electromagnetic force actuated on the disabled spacecraft.

Yunnan power grid has a large-scale hydropower station whereby the power generated at the station is been transmitted via high-voltage direct current (HVDC) transmission lines under asynchronous operation mode. In the system performance test of Yunnan asynchronous operation, 0.05 Hz ultra-low frequency oscillation occurred in the grid. We analyzed the damping characteristics of different types of units and figured out that the negative damping characteristic of the hydropower units are mainly responsible for the ultra-low frequency oscillation. There is a tendency for ultra-low frequency oscillation in a regional power grid with high ratio of hydropower penetration which transmits electricity using HVDC. The water hammer effect of hydraulic turbine influences the damping characteristic of the hydropower unit while the governor control gain influences the strength of the damping. By setting reasonable governor control gain and optimizing the dead-zone of HVDC frequency limit controller the ultra-low frequency oscillation of the Yunnan asynchronous system can be effectively curbed. Simulation results and system performance test verified the effectiveness of the method.

Strong magnetoelectric (ME) coupling can be realized in multiferroic heterostructures, which have led to a variety of devices. Here, a novel electrostatically tunable frequency selective surface (FSS) with PZT/FeGaB films is reported, which shows a high resonant frequency tunability. A high X to Ku band resonant frequency tunability of f = 2.75 GHz or f/f= 24% was demonstrated in the FSS with PZT/FeGaB films, which was 10 times of the similar FSS structure with only FeGaB film. This electrostatically tunable FSS with strong ME coupling will provide great opportunities for more energy efficient, less noisy, compact and light-weight microwave devices with frequency tunabilities.

To test airborne avionics device, it is necessary to provide signal stimulus for the device under test (DUT) to simulate the real work environment. This paper proposes a hardware module which used to signal generate and analyze. The hardware structure and diagram of logic design are described. The generated waveforms and measurement results are presented. This test module combined with other necessary modules can achieve the test of L band airborne avionics such as ATC, TCAS and TACAN.

Micro cutting is a promising manufacturing method to obtain good surface integrity. Surface roughness shows size effect when the uncut chip thickness is smaller than the cutting edge radius. A special micro slot on the flank face of cutting tools was manufactured with discharge. Two groups of micro orthogonal cutting were conducted. The surface roughness of machined surface was measured and compared to each other. The results show that surface roughness decreases first and then increases with the ratio of uncut chip thickness to cutting edge radius. The surface machined with micro slot is better than that of without micro slot due to the micro slot restrain the back side flow of work piece based on the finite element model.

This paper takes the seismic performance of the existing building evaluation in Wuhan, analysis of the existing building on the seismic performance, and extract a certain characteristic parameters for quick retrieval and identification, proposed the idea of the of earthquake damage prediction database, build and improve the based information of the construction earthquake damage prediction, establish a fast city buildings earthquake damage prediction system.

A common mechanical model of ball-end milling cutter is analyzed in this paper, and take advantage of the orthogonal experiment method to make experiment of milling to identify the milling force coefficients with the titanium alloy material as the test object.Then put the coefficients in the mechanical model of ball to use MATLAB software to predict the milling force. The results of experiment and results of simulation are basically identical, it shows that the mechanics model of ball milling is proved to be correct.

Tool point frequency response function (FRF) is the key parameters to predict the milling stability in high-speed milling. Receptance coupling substructure analysis (RCSA) is described to predict the tool point FRF. The major difficulties in RCSA are the identification of joint connection parameters and the obtaining of FRFs of substructure. This paper separation of the milling system into three substructures: the machine-spindle-holder taper, the extended holder-tool shank, and the tool extended portion. Develop the connection model compose of linear and rotational springs and dampers. Determine the substructure FRF by measurement and Euler-Bernoulli beam model. Tool point FRF is obtained by coupling the substructure FRFs through the connection model by RCSA.

By disrupting the regenerative effect, milling cutters with variable-pitch are usually used to improve stability. Since high interrupted cutting processes, such as low radial immersion case, will result in more nonlinear phenomena and some consequent differences of stability chart, in this paper, an improved semi-discretization algorithm is utilized to predict the stability lobes for variable-pitch milling under low radial immersion ratios, the focus of the current manuscript is to investigate the stability trend caused by tool geometries. In addition, the chart differences in the cases of low and high radial immersion milling are also discussed by comparisons. Under certain combinations of parameters, some phenomena, like bunch of isolated island and flip bifurcation region are described, and some influences of tool geometries on stability trends are shown and explained.

The mean Hounsfield value of 99.9% ethanol did get down to -190 Hounsfield units (HU), there was a linear correlation between ethanol concentration and Hounsfield values. We aimed to evaluate whether sclerotherapy with estimated ethanol concentration was helpful in improving the success rate for treatment of symptomatic simple hepatic cysts.Forty-five patients with 52 symptomatic simple hepatic cysts were enrolled in this study. Twenty-one patients (24 cysts, group A) were treated by sclerotherapy without estimated ethanol concentration and 24 patients (28 cysts, group B) with estimated ethanol concentration. The Chi-square test and Mann-Whitney U test were used to compare the difference in characteristics and treatment outcomes of the subjects between these two groups.The mean cyst size before and after treatment were 8.4cm and 2.3cm, respectively, in group A, and 8.2cm and 0.8cm, respectively, in group B. There was no significant difference in the initial size of hepatic cysts between the groups. However, the final size was significantly smaller in group B (P=0.022). The mean ethanol exposure time was 18.3minutes in group B, which was less than that in group A (P0.001). The success rate was significantly higher in group B (96.4%) than in group A (70.8%) (P=0.03). There were no major complications in either group.CT-guided sclerotherapy with estimated ethanol concentration yields better results than those without estimated ethanol concentration in the treatment of symptomatic simple hepatic cysts.

The impeller as the key part of aircraft engine components, and the impeller blade surface is complex, and it is a typical complex difficult machining parts. Five-axis NC machining is the important means to realize sculptured curved surface parts machined with high quality and efficiency. In this paper, in view of the interference problems occurred in the process of impeller five-axis NC machining tool path generating, the configuration space method is proposed to tackle the problem of interference, cutter location point as constraint conditions, the cutter position is described by using two angle parameters, optimization of cutter position, tool path generated without interference, improve the impeller machining quality and production efficiency. Finally, as a case study of a certain type of impeller, it makes arithmetic realization combining with MATLAB.

For the high speed cutting process of hardened 45 steel (45HRC), a finite element simulation of cutting deformation, cutting force and cutting temperature is finished with the large general finite element software ABAQUS. Through the building of geometry model, material model and heat conduction model, also the determination of boundary conditions, separation rule and friction condition, a thermal mechanical coupling finite element model of high speed cutting for hardened 45 steel is built. The serrated chip, cutting force and cutting temperature can be predicted. The comparison of experiment and simulation shows the validity of the model. The influence of cutting parameters on cutting process is investigated by the simulation under different cutting depthes and rake angles. The results show that as the increase of rake angle, the segment degree, cutting force and cutting temperature decrease. But the segment degree, also the cutting force and cutting temperature increase with the increase of cutting depth. This study is useful for the selection of cutting parameters of hardened steel.

Using five-axis equipment for NC machining of free-form surface is an effective way to improve machining quality and machining efficiency, the surface shape and the five coordinate of the complexity of the machine tool movement led to its tool path planning technology is difficult. The paper aimed at the five coordinate NC machining of free-form surface and puts forward a five-axis NC machining method based on triangular facet model. The research based on triangular facet model, using constant scallop height method to calculate the step distance and improve the cutting efficiency to a great extent. In the process, tool path is generated, combining with the method of configuration space interference free.

As one of the most widely used energy storage systems, lithium-ion batteries are attracting more and more attention, and the estimation of lithium-ion batteries remaining useful life (RUL) becoming a critical problem. Generally, RUL can be predicted in two ways: physics of failure (PoF) method and data driven method. Due to the internal electro-chemical reactions are either inaccessible to sensors or hard to measure; the data-driven method is adopted because it does not require specific knowledge of material properties. In this paper, three data-driven algorithms, i.e., Support Vector Machine (SVM), Autoregressive Moving Average (ARMA), and Particle Filtering (PF) are presented for RUL prediction. The lithium-ion battery aging experiment data set has been trained to implement simulation. Based on the RUL prediction result, we can conclude that: (1) ARMA model achieved better result than SVM, however, the result shows a linear trend, which fail to properly reflect the degradation trend of the battery; (2) SVM often suffers from over fitting problem and is more suitable for single-step prediction; and (3) PF approach achieved a better prediction and reflected the trends of degradation of the battery owing to its combined with specific model.

Innovation capability evaluation plays a vital role on promoting and ensuring the persistent and in-depth work of scientific research activities in university. Some scholars have proposed a variety of qualitative innovation capability evaluation methods, however, how to separate from subjective judgments and how to describe the vagueness of capability information are still the most important problems. This study proposed fuzzy clustering method and Based on this method 41 universities innovation capability evaluation of Jiangsu province is processed. This study provided a novel means to solving practical innovation capability evaluation problems.

Objective: Side population (SP) cells may play a crucial role in tumorigenesis and the recurrence of cancer. Many kinds of cell lines and tissues have demonstrated the presence of SP cells, including several gastric cancer cell lines. This study is aimed to identify the cancer stem-like cells in the SP of gastric cancer cell line MKN-45. Methods: We used fluorescence activated cell sorting (FACS) to sort SP cells in the human gastric carcinoma cell line MKN-45 (cells labeled with Hoechst 33342) and then characterized the cancer stem-like properties of SP cells. Results: This study found that the SP cells had higher clone formation efficiency than major population (MP) cells. Five stemness-related gene expression profiles, including OCT-4, SOX-2, NANOG, CD44, and adenosine triphosphate (ATP)-binding cassette transporters gene ABCG2, were tested in SP and MP cells using quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). Western blot was used to show the difference of protein expression between SP and MP cells. Both results show that there was significantly higher protein expression in SP cells than in MP cells. When inoculated into non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, SP cells show higher tumorigenesis tendency than MP cells. Conclusions: These results indicate that SP cells possess cancer stem cell properties and prove that SP cells from MKN-45 are gastric cancer stem-like cells.

This paper uses modern spectrum setimation to process stepped-frequency signals which have extracted to obtain high resolution range profile. This paper use FPE criteria and AIC criteria to estimate the order of AR model, and linear prediction is used to test the performance of AR model. Compared with conventional IFFT processing, the results of spectrum estimation is satisfactory, and the exact location of high resolution range profile is determined.

In many practical applications of wireless power transfer (WPT) system, high power transmission efficiency is required and has been widely studied as an important issue. This paper presents and analyzes a Series-Parallel compensated WPT system with a Z-source inverter network inserted. To obtain higher efficiency, asymmetrical voltage-cancellation (AVC) control is applied and the ZVS operation is achieved. The AVC control algorithm should also be modified to help Z-source inverter to realize voltage boosted and fully utilize the null state existed in the AVC control. On account of the ZVS operation, the power factor of the system decreases inevitably, but it decreases less in Series-Parallel compensated topology than in Series-Series compensated topology. To verify the feasibility of the proposed method, a small-signal model is fully analyzed, and a controller is designed to help to realize AVC control. Finally, a simulation model is established and the result agrees with the analysis.

This paper presents an efficient modular electromechanical transient modeling method of unified power flow controller (UPFC) based on voltage source converter (VSC). The most distinctive advantage of the modeling method proposed in this paper is that it can be applied to the simulation of different UPFC structures and access ways. This method is based on basic VSC-based UPFC rules. Firstly, transform different VSC topology structures into unified and equivalent current circuit. Next, divide UPFC into four modules: series module, parallel module, DC module and control module. Then, calculate each module in turn. Finally, solve the UPFC part and the network equation alternately until the convergence is reached. This modeling method has already been applied and proved effective in “PSD” power system analysis tools. The accuracy of the model is verified by the example analysis and the comparison with the Real Time Digital Simulator (RTDS) dynamic test curve.

Islanded operation of HVDC sending system can reduce the influence of HVDC fault on the parallel AC system, enhance the security of the system and increase the transmission capacity. Due to relatively small system inertia and ESCR, there are difficulties of the frequency and voltage control in the islanded sending system. The conventional analysis are focuses on the process after HVDC bipolar trip. An unexpected bipolar trip occurred after the monopolar trip test in the onsite commissioning of Yun-Guang HVDC islanded operation on May 26th, 2013. Process analysis shows that direct causes of the bipolar trip are the reverse-action of PSS, the low ESCR, and frequency adaptability of the HVDC overvoltage protection. An supplymentary test, concentrating on frequency adaptability of the HVDC overvoltage protection, was conducted on July 14th, 2013. But the temporary overvoltage risk still existed in the supplymentary test. Wide-area PSS and high-voltage-side voltage control are proposed to solve temporary overvoltage problem after HVDC trip. In the EMTDC/PSCAD simulation, overvoltage decreases about 60 kV to 80 kV by using these two measures simultaneously.

This paper concentrates on the design approaches of attitude control with momentum management, which is still a difficult and hot problem, especially for spacecraft electromagnetic docking technology. The integrated controller design frame is firstly brought forward, and sequence solutions with magnetic dipoles are provided. After the magnetic design, the extended state model of attitude control with momentum management is derived. Considering the magnitude, rate and bandwidth constraints of attitude control mechanism, as well as requirements of spacecraft docking mission, several approaches including linear, nonlinear and optimal methods for a single satellite or multiple satellites are studied. A simple simulation case is presented to verify the feasibility and performance of these approaches. At last, some conclusions are given.

This paper firstly puts forward a novel concept of space-based radiography which could be used to detect the interior of spacecraft, and investigates the relevant four kinds of formation patterns with application to the disabled spacecraft, i.e., patterns of external structure reconstruction, with the same or different relative orbit, with the spiral relative orbit. Taking advantages of the cyclic pursuit theory and the extended state observer (ESO), the three kinds of pursuit strategies and the robust coordinated cyclic pursuit controllers of each formation patterns are designed. In addition, the tuning method and formulation of controller parameter with respect to the required formation pattern are also derived and presented. Simulation results verify that the cyclic pursuit controller could enable all required formation patterns with certain robust capability, which could be enhanced by the feedback compensation of ESO-based estimates.

This paper designs a visual 3D CAD framework based on Vega Prime/Creator. This framework solves problems such as the customization of Vega Prime application class, establishment of multichannel and multi-view scenes, transmitting method of plenty of view pointers, management of data with diversified source, multithreading communication, movement of the model and its view point controlling. In the end, this paper developed a real-time interactive CAD system using this framework, which verifies the validity of the framework.

Transcutaneous energy transmission (TET) systems are designed to deliver power from an in vitro primary power source to in vivo implantable secondary over relatively large air gaps via magnetic coupling. This paper proposes an optimization method with given output power to meet different practical application. The transmission efficiency is the objective function; primary and secondary coils are design variables; constraints are based on bifurcation phenomenon and components peak over-voltage and peak withstand current. We have used MATLAB/ SIMULINK to verify the analytical results.