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Wang A, Duan Q, Wu J, Liu X, Sun Z. The expression of ADAMTS13 in human microvascular endothelial cells. Blood Coagul Fibrinolysis. (2016) 27:464-6. doi: 10.1097/MBC.0000000000000405 13. ...doi:10.3389/fneur.2019.00772 pmid:31379722 pmcid:PMC6650536 fatcat:xc76qvxi5bfivkaoi7wbtke3u4
The travelling salesman problem (TSP) of space trajectory design is complicated by its complex structure design space. The graph based tree search and stochastic seeding combinatorial approaches are commonly employed to tackle the time-dependent TSP due to their combinatorial nature. In this paper, a new continuous optimization strategy for the mixed integer combinatorial problem is proposed. The space trajectory combinatorial problem is tackled using continuous gradient based method. AarXiv:2109.01821v1 fatcat:xrlkohsa7jgsnargsoislawe6e
more »... us mapping technique is developed to map the integer type ID of targets on the sequence to a set of continuous design variables. Expected flyby targets are introduced as references and used as priori to select the candidate target to fly by. Bayesian based analysis is employed to model accumulated posterior of the sequence and a new objective function with quadratic form constraints is constructed. The new introduced auxiliary design variables of expected targets together with the original design variables are set to be optimized. A gradient based optimizer is used to search optimal sequence parameter. Performances of the proposed algorithm are demonstrated through a multiple debris rendezvous problem and a static TSP benchmark.
Currently, it appears that there is a lack of understanding related to the role of SSF, in the two-phase behavior of the deceleration history, which is an issue discussed recently in the impact dynamics field. This paper analytically and numerically focuses on the effect of SSF on the projectile deceleration characteristic of concrete-like targets. Firstly, the penetration process according to the two-phase feature of the projectile deceleration is revised, where analytical results indicatedoi:10.3390/ma13214733 pmid:33113988 fatcat:ypomd3oulfby5a4le4ldi6jzai
more »... the SSF has a phased feature corresponding to the two-phase behavior of the deceleration history. Furthermore, a series of numerical simulations are conducted to understand the role of SSF more clearly. Simulation results show a similar conclusion to the analyses of the two-phase penetration process; at the range below a certain critical striking velocity, adding friction can reproduce the experimental data; when exceeding the critical striking velocity, the simulated results without considering friction are closest to the experimental data. Hence, it could be gained that the role exchange between the SSF and the dynamic term contributes to the two-phase penetration behavior for concrete-like materials. This indicates that the sensitivity of SSF to the penetration process is one of the factors driving the two-phase feature.
Further, a dynamic task clustering strategy was designed by Wu G in 2017  . ... In 2013, Wu G  proposed a two-phase scheduling method that considers task clustering of Earth observation satellites. ...doi:10.3390/a12110231 fatcat:zc4lvsdpdng2bltbt3ogm3aurm
In the clinical diagnosis and treatment of brain tumors, manual image reading consumes a lot of energy and time. In recent years, the automatic tumor classification technology based on deep learning has entered people's field of vision. Brain tumors can be divided into primary and secondary intracranial tumors according to their source. However, to our best knowledge, most existing research on brain tumors are limited to primary intracranial tumor images and cannot classify the source of thearXiv:2104.02331v1 fatcat:yqq2nqgqvncgdg4pr77jgq5tl4
more »... or. In order to solve the task of tumor source type classification, we analyze the existing technology and propose an attention guided deep convolution neural network (CNN) model. Meanwhile, the method proposed in this paper also effectively improves the accuracy of classifying the presence or absence of tumor. For the brain MR dataset, our method can achieve the average accuracy of 99.18% under ten-fold cross-validation for identifying the presence or absence of tumor, and 83.38% for classifying the source of tumor. Experimental results show that our method is consistent with the method of medical experts. It can assist doctors in achieving efficient clinical diagnosis of brain tumors.
The safety of on-orbit satellites is threatened by space debris with large residual angular velocity and the space debris removal is becoming more challenging than before. This paper explores the non-contact despinning and traction problem of high-speed rotating targets and proposes an eddy current brake and traction technology for space targets without any propellant consumption. The principle of the conventional eddy current brake is analyzed in this article and the concept of eddy currentdoi:10.3390/aerospace8020024 fatcat:l7lkvwzj4bdhvdqanffk7hpori
more »... ke and traction without propellant is put forward for the first time. Secondly, according to the key technical requirements, a brand-new structure of a satellite generating artificial magnetic field is designed accordingly. Then the control mechanism of eddy current brake and traction without propellant is analyzed qualitatively by simplifying the model and conditions. Then, the magnetic pulse control method is proposed and analyzed quantitatively. Finally, the feasibility of the technology is verified by the numerical simulation method. According to the simulation results, the eddy current brake and traction technology based on magnetic pulses can make the angular speed of target decrease linearly without propellant during the process. This technology has huge advantages compared with conventional eddy current brake technology in terms of efficiency and reduced propellant consumption.
Microsatellites have attracted a large number of scholars and engineers because of their portability and distribution characteristics. The ground station suitable for microsatellite service has become an important research topic. In this paper, we propose a networked ground station and verify it on our own microsatellite. The specific networked ground station system consists of multiple ground nodes. They can work together to complete data transmission tasks with higher efficiency. Afterdoi:10.3390/s22093569 pmid:35591261 pmcid:PMC9102216 fatcat:a2r4srb2d5hrhly6flpo2ircsm
more »... ing our microsatellite project, a reasonable distribution of ground nodes is given. A cloud computing model is used to realize the coordination of multiple ground nodes. An adaptive communication system between satellites and ground stations is used to increase link efficiency. Extensive on-orbit experiments were used to validate our design. The experimental results show that our networked ground station has excellent performance in data transmission capability. Finally, the specific cloud-computing-based ground station network successfully completes our satellite mission.
Fabrication of polymer composite fibers embedding ultra-long micro/nanowires via an iterative melt co-drawing and bundling technique is reported in this study. The poly(methyl methacrylate) (PMMA) porous array templates were prepared with section-cutting the PMMA/polystyrene (PS) (shell/core) composite fibers and dissolution of inner PS. The results showed that the PS cores or pores in the PMMA matrix are regularly arranged with hexagonal, and their diameter and spacing exhibits a uniformdoi:10.3390/nano11040939 pmid:33917057 fatcat:46br5dzxjjbapgcamgonw52cxq
more »... bution. Especially, the core diameter can be precisely controlled from millimeter-scale to nanometer-scale by multi-step melt co-drawing. Based on the PMMA porous array templates, the Cu nanowires were successfully prepared by electrochemical deposition. Moreover, to fabricate PMMA ultra-long micro/nanowires, the composite fibers with converse shell/core component of PS/PMMA were initially prepared, and then the outer PS was dissolved. The obtained PMMA micro/nanowires were characterized with smooth complete orientation structure. The study provides an experimental basis for fabricating such polymer composite fibers, micro/nano porous array templates, and micro/nanowires with precise and controllable manner to meet the real application requirements.
District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demanddoi:10.1016/j.egypro.2019.01.743 fatcat:ao7neoracfgqrcft3g5ss6vwpe
more »... door temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations. Abstract The alternative materials to remove Hg 0 from energy utilization sectors is crucial to mercury control in atmosphere. CeO2 based catalysts were prepared by an incipient wetness impregnation (IWI) method. A novel Hg 0 and Hg T temperature-programmed surface reaction (Hg 0 -Hg T -TPSR) was proposed in this study for the investigation of the prepared CeO2 based catalysts with the qualitative and quantitative analyses. The characteristic temperatures, the areas of adsorption region and desorption region, and activation energy with reaction kinetics were investigated to evaluate the performance. It was found that 2wt% Ce catalyst has the best mercury removal performance with the highest Hg 0 removal ability and the lowest Ea. There was also small amount of Hg 2+ detected which indicated the catalytic effect contributed. The results suggested that 2wt% Ce based binary catalysts could be the potential candidates to be investigated in the future study. Abstract The alternative materials to remove Hg 0 from energy utilization sectors is crucial to mercury control in atmosphere. CeO2 based catalysts were prepared by an incipient wetness impregnation (IWI) method. A novel Hg 0 and Hg T temperature-programmed surface reaction (Hg 0 -Hg T -TPSR) was proposed in this study for the investigation of the prepared CeO2 based catalysts with the qualitative and quantitative analyses. The characteristic temperatures, the areas of adsorption region and desorption region, and activation energy with reaction kinetics were investigated to evaluate the performance. It was found that 2wt% Ce catalyst has the best mercury removal performance with the highest Hg 0 removal ability and the lowest Ea. There was also small amount of Hg 2+ detected which indicated the catalytic effect contributed. The results suggested that 2wt% Ce based binary catalysts could be the potential candidates to be investigated in the future study.
Wu et al. [38, 43] improved the clique partition algorithm by considering the priorities of vertices (original tasks) and adopted it in the task clustering phase. ...doi:10.3390/rs13122377 fatcat:h7bxhdyxq5grfid4bjmspiicwy
High demands for industrial networks lead to increasingly large sensor networks. However, the complexity of networks and demands for accurate data require better stability and communication quality. Conventional clustering methods for ad-hoc networks are based on topology and connectivity, leading to unstable clustering results and low communication quality. In this paper, we focus on two situations: time-evolving networks, and multi-channel ad-hoc networks. We model ad-hoc networks as graphsarXiv:2108.00600v2 fatcat:zfsjuxyv6nbfpjanjjyciyicey
more »... d introduce community detection methods to both situations. Particularly, in time-evolving networks, our method utilizes the results of community detection to ensure stability. By using similarity or human-in-the-loop measures, we construct a new weighted graph for final clustering. In multi-channel networks, we perform allocations from the results of multiplex community detection. Experiments on real-world datasets show that our method outperforms baselines in both stability and quality.
Recent neuropsychological research has begun to reveal that neurons encode information in the timing of spikes. Spiking neural network simulations are a flexible and powerful method for investigating the behaviour of neuronal systems. Simulation of the spiking neural networks in software is unable to rapidly generate output spikes in large-scale of neural network. An alternative approach, hardware implementation of such system, provides the possibility to generate independent spikes preciselydoi:10.1007/s11571-011-9170-0 pmid:22942919 pmcid:PMC3179547 fatcat:czem7mnllbdltpsmpkx3i67rga
more »... d simultaneously output spike waves in real time, under the premise that spiking neural network can take full advantage of hardware inherent parallelism. We introduce a configurable FPGA-oriented hardware platform for spiking neural network simulation in this work. We aim to use this platform to combine the speed of dedicated hardware with the programmability of software so that it might allow neuroscientists to put together sophisticated computation experiments of their own model. A feed-forward hierarchy network is developed as a case study to describe the operation of biological neural systems (such as orientation selectivity of visual cortex) and computational models of such systems. This model demonstrates how a feed-forward neural network constructs the circuitry required for orientation selectivity and provides platform for reaching a deeper understanding of the primate visual system. In the future, larger scale models based on this framework can be used to replicate the actual architecture in visual cortex, leading to more detailed predictions and insights into visual perception phenomenon.
Actually, Wu & Wu (1993) proved that, at least in the framework of the derivative moment transformation, the aerodynamic force cannot be determined solely with longitudinal variables. ... Following the work of Lighthill (1957) and Hayes (1957) , Wu et al. (2006) proposes a simple and general way to re-derive vorticity jump condition in three-dimensional general steady flow (with small ...arXiv:2012.11320v1 fatcat:tb4vyyfyxja7tj7dphib3n62oi
In order to develop online washing process of a carrier-based aircraft engine and improve washing efficiency, washing equipments were employed in cold operation state to carry out experimental study on structural strength of spray frame, selection of nozzle and determination of injection parameters of online washing spray system, determination of washing injection timing, determination of drying procedure, liquid-washing experiments of different concentrations and water-washing experiments anddoi:10.1051/matecconf/201711404009 fatcat:7ovszn5zhbeynd6ab5wzfy4aha
more »... o on. The results show that if engine is washed in cold operation state, mid-nozzle with upward offset angel of 7 30 can be selected and the feed liquid pressure provided by washing vehicle is 0.9Mpa. The start time is 20s after an engine cold start-up, and sustains 30s for once washing. After a liquid-washing with the use of washing fluid, the liquid concentration of which is no more than 20%, twice water-washing can be carried out to rinse the almost all cleaning agent remaining in the engine runner(the residue is less than 1%). The engine can be thoroughly dried by power-on operation, the procedure of which is engine operating 2min in ideal state, then 2min in state of n2 85 and 2min of ideal state lastly. Washing will not affect the engine function. a Corresponding
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