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Collaborative edge computing (CEC) can realize the cooperation and integration of heterogeneous resources distributed in adjacent areas, increasing the overall resource utilization efficiency. In a CEC-supported heterogeneous vehicular network composed of different access solutions, including cellular vehicle-to-everything (C-V2X) and dedicated short-range communications (DSRC), good network connections can guarantee timely access to edge resources. How to maintain stable and high-quality network connections for vehicles is a crucial issue. With traditional received signal strength (RSS)-based handover schemes, vehicles may encounter severe ping-pong effects and even direct handover failures leading to data packet loss. In this article, to overcome the frequent handover problem caused by vehicles' high-speed motion and the ever-changing network environment, we propose a trajectory prediction-based handover scheme. In this scheme, the sojourn time of a vehicle staying in each candidate network's coverage can be obtained through a social long short-term memory (social-LSTM)-based prediction model. Together with the signal strength, available bandwidth, and cost, the sojourn time is also taken as a handover decision attribute parameter. Simulation results show that our proposed scheme can reduce the number of handovers effectively.

In the flue gas ammonia desulfurization process of the coal chemical industry, ammonium sulfate slurry in the desulfurization tower often foams and overflows, which wastes resources and pollutes the environment. The solution to this problem remains largely unknown. This paper aims to reveal the causes of foaming by analyzing foam composition, ammonia desulfurization process raw material source, and characteristics of the flue gas source of the coal chemical industries. It is seen that the organic carboxylate ammonium salt surfactant in the slurry was the main cause of ammonium sulfate slurry foaming. Moreover, due to ammonium sulfate crystals and ash in foam forming a skeleton to support the foaming structure, the foam was not easy to break. More importantly, an appropriate defoaming agent was screened and optimized by an ammonia desulfurization tower simulated device in the laboratory. The YLZ-3 compound defoaming agent, with the optimal defoaming efficiency, was obtained by combining a polyether siloxane copolymer, n-octyl alcohol, fumed silica, and deionized water. It had a good temperature stability and little influence on the ammonium sulfate slurry drying time. However, defoaming agent addition could affect the ammonium sulfate crystal form. The foam overflowing could be controlled by spraying the defoaming agent from the top of the tower. Thus, the problem of bubbling overflow of the ammonia desulfurization tower could be resolved very well.

Radiation-induced lung injury (RILI) is a common serious complication and dose-limiting factor caused by radiotherapy for lung cancer. This study was to investigate radioprotective effects of grape seed proanthocyanidins (GSP) on normal lung as well as radiosensitizing effects on lung cancer. In vitro, we demonstrated radioprotective effects of GSP on normal alveolar epithelial cells (MLE-12 and BEAS/2B) and radiosensitizing effects on lung cancer cells (LLC and A549). In vivo, we confirmed these two-way effects in tumor-bearing mice. The results showed that GSP inhibited tumor growth, and played a synergistic killing effect with radiotherapy on lung cancer. Meanwhile, GSP reduced radiation damage to normal lung tissues. The two-way effects related to the differential regulation of the MAPK signaling pathway by GSP on normal lung and lung cancer. Moreover, GSP regulated secretion of cytokines IL-6 and IFN-γ and expression of p53 and Ki67 on normal lung and lung cancer. Our findings suggest that GSP is expected to be an ideal radioprotective drug for lung cancer patients who are treated with radiotherapy.

Human perception of an object’s skeletal structure is particularly robust to diverse perturbations of shape. This skeleton representation possesses substantial advantages for parts-based and invariant shape encoding, which is essential for object recognition. Multiple deep learning-based skeleton detection models have been proposed, while their robustness to adversarial attacks remains unclear. (1) This paper is the first work to study the robustness of deep learning-based skeleton detection against adversarial attacks, which are only slightly unlike the original data but still imperceptible to humans. We systematically analyze the robustness of skeleton detection models through exhaustive adversarial attacking experiments. (2) We propose a novel Frequency attack, which can directly exploit the regular and interpretable perturbations to sharply disrupt skeleton detection models. Frequency attack consists of an excitatory-inhibition waveform with high frequency attribution, which confuses edge-sensitive convolutional filters due to the sudden contrast between crests and troughs. Our comprehensive results verify that skeleton detection models are also vulnerable to adversarial attacks. The meaningful findings will inspire researchers to explore more potential robust models by involving explicit skeleton features.

A highly customizable hybrid sensor system, composed of a silicon integrated circuit (IC) chip and an organic field effect transistor (OFET) transducer, is proposed for Internet of Everything (IoE). In such a system, the silicon IC chip performs high performance and complex signal processing, and the OFET transducer provides flexible or conformable large area coverage and more friendly interfaces to integrate different sensing materials. A low trap-state density OFET (LTDOFET) technology is developed for such a hybrid system, owning features of low-cost solution printing processes, low operation voltage and excellent operational stability. This technology has been implemented with various materials and processes, indicating its generality. Several sensor applications built based on this device technology are also reviewed, proving the LTDOFET technology would be promising for highly customizable sensor systems towards the IoE era.

The conventional target tracking approaches are presented under the assumption of the point target. In multi extended target scenarios, the tracking performance of these approaches may be greatly decreased. The the Gaussian mixture (GM) implementation of the probability hypothesis density (PHD) (named as the ET-GM-PHD approach) has been presented for applying the GM-PHD approach into extended target tracking. However, it has been proposed under the linear models. In fact, most of targets are moving with nonlinear models. Thus, we, in this paper, present a square-root cubature information filter (SCIF) based ET-GM-PHD approach. To be more specific, we, first, employ the cubature points to predict the mean and the square-root factor of covariance. Then, the information forms of the mean and square-root of covariance has been used to update the mean and covariance of GM component. Meanwhile, we integrate the gating method into our method for saving computational complexity. Owing to the significant tracking performance of the SCIF method, our approach can estimate states and number of multi extended targets in nonlinear scenarios. In addition, we also propose an observation driven method to initiate the birth intensity. As for our method, the conditional probability has been adopted to describe the association between the target and its corresponding observations. With such a probability, the most possible partition, where the estimated targets belong to, can be approximated. Thus, the birth intensity can be estimated by removing the cells associated with the estimated targets. Since we use the estimated targets to initiate the birth intensity, our approach can initiate the birth intensity adaptively. The simulation results prove the effectiveness of our approach.

Energy Internet has been considered as a promising alternative to the traditional power grid. In order to improve the energy efficiency of an Energy Internet, energy routers are treated as a significant power conversion device to increase the penetration of renewable sources. Different from previous studies which only consider the shortest path for energy routers, a virtual energy routing strategy involving renewable energy integration is proposed in this paper to reduce the network loss, considering both transmission and conversion efficiency. To address above, the discrete particle swarm optimization (DPSO) algorithm is studied and applied. The effectiveness of the proposed virtual energy routing strategy is validated by an Energy Internet platform integrated with photovoltaic (PV) generation and energy-storage.

Solid insulators applying functionally graded material (d-FGM) have spatially non-uniform dielectric properties. The d-FGM insulator is effective on insulation performance improvement without complicating the structure; however, the fabrication of such insulators remains a challenge. To investigate the feasibility of 3D printing technology on d-FGM, we designed and fabricated a conductivity non-uniform insulator and tested its surface flashover characteristics. First, a modified genetic algorithm is employed to design the conductivity distribution in the non-uniform insulator. The designed insulator is then fabricated using a 3D printing process named fused deposition modeling (FDM), in which we verified the applicability of 3D printing materials on electrical insulation. Finally, compared to the uniform insulator, the surface flashover voltages of non-uniform insulators were improved by 23% in SF6 and 20% in vacuum. From above, we envision potential application feasibility for 3D printing of d-FGM in practical insulation design.

As a common serious complication of thoracic radiotherapy, radiation-induced pulmonary fibrosis (RIPF) severely limits radiation therapy approaches. Epithelial–mesenchymal transition (EMT) is a direct contributor to the fibroblast pool during fibrogenesis, and prevention of EMT is considered an effective strategy to inhibit tissue fibrosis. Our previous study revealed that TANK-binding kinase 1 (TBK1) regulates EMT in lung cancer cells. In the present study, we aimed to investigate the therapeutic potential of targeting TBK1 to prevent RIPF and EMT progression. We found radiation-induced EMT and pulmonary fibrosis in normal alveolar epithelial cells and lung tissues. TBK1 knockdown or inhibition significantly reversed EMT in vivo and in vitro and attenuated pulmonary fibrosis and collagen deposition. Moreover, we observed that TBK1 was elevated in a time- and dose-dependent manner by radiation. Meanwhile, radiation also induced time- and dose-dependent activation of AKT and ERK, each of whose inhibitors suppressed radiation-induced EMT. Intriguingly, silencing of TBK1 with shRNA also blocked the radiation-induced activation of AKT and ERK signaling. The ERK inhibitor did not obviously affect the expression of TBK1 or phosphorylated AKT, while AKT inhibition suppressed activation of ERK without changing the expression of TBK1. Finally, we found that a TBK1 inhibitor inhibited inflammatory cytokine expression in a RIPF model and Amlexanox protected normal cells and mice from ionizing radiation. In conclusion, our results indicate that the TBK1–AKT–ERK signaling pathway regulates radiation-induced EMT in normal alveolar epithelial cells, suggesting that TBK1 is a potential target for pulmonary fibrosis prevention during cancer radiotherapy., Lung cancer: Suppressing fibrosis during radiotherapy The risk of scarred tissues and respiratory distress during radiation treatment of lung cancer could be reduced by targeting an enzyme that alters healthy cells. Lung cancer radiotherapy often causes pulmonary fibrosis, excessive growth of fibrous tissues in the lungs, involving the transition of normal epithelial cells into an invasive form of multipotent stem cells. The development of pulmonary fibrosis limits the clinical application of radiotherapy. Hongjin Qu and co-workers at the Second Military University in Shanghai, China, previously demonstrated that the TANK-binding kinase 1 (TBK1) enzyme regulates this transition. Now, the team have shown that levels of TBK1 itself increased during radiation treatment, together with two proteins that would normally suppress alterations in healthy cells. Inhibiting TBK1, both in cell cultures and mouse models, reversed the cell transitions and prevented pulmonary fibrosis.

In this paper, the research status of topology and control strategy of energy storage grid-connected system is analyzed, and aiming at the working characteristics of the repurposed battery, a cascade power electronic transformer (CPET) with independent DC output is proposed. The working principle of current fed isolated bidirectional DC-DC converter (CF-IBDC) and cascaded H-bridge (CHB) is analyzed, and the decoupling control strategy is designed. In this paper, a hierarchical control strategy is designed for the repurposed battery energy storage (RBES) grid-connected system based on CPET, which consists of three layers: energy layer, power layer, and state of charge (SOC) layer. The energy layer responds to active and reactive power scheduling instructions, the power layer controls the grid-connected current and tracks the grid voltage, and the SOC layer equates the charged state of repurposed batteries. A 3 MVA/12 kV three-phase grid-connected simulation system was established, and a 1 kW single-phase system experiment platform was designed. The simulation and experimental results can verify the correctness of the theoretical analysis and the feasibility of the control strategy.

The existing single machine working mode of live working robots cannot meet the computational power requirements of artificial intelligence high-precision algorithm, and it is difficult to adapt to the complex working scene, and cannot be applied to the scene where a large number of robots work at the same time to generate massive data management and control. In view of the existing shortcomings, this paper analyzes and compares the working modes of existing power grid inspection robots and live working robots, and proposes an intelligent management and control method for live working robots based on cloud and edge computing terminals. By deploying different parts of deep learning algorithm in cloud and edge computing terminal, the problems existing in the previous working mode are solved. A typical example of live working robot scene in substation is analyzed. The results show that the intelligent control method proposed in this paper can meet the computational power requirements of artificial intelligence deep learning, neural network coordinated control, recognition and control model self-learning, self-renewal and other high-precision algorithm, and can be applied to the scene of complex environment or a large number of robots working at the same time to produce massive data control.

Image enhancement is an essential processing for raw infrared images to improve contrast. In this paper, an infrared image enhancement method is proposed to solve the problem of over-enhancement on background in occurrence probability histogram based methods and the problem of uneven enhancement for targets in the saliency weight based method. First, the saliency histogram is constructed, where the bin values of target-related intensity levels are significantly larger than the bin values of background-related intensity levels. According to the value distribution of bins in saliency histogram, the intensity levels with several largest bin values, defined as the salient intensity levels, are segmented. Salient intensity levels are separated further away from non-salient levels to improve the contrast between targets and background. Second, salient intensity levels are divided into groups and each group is related to targets of a certain range of temperatures. Bin values of salient intensity levels are reallocated within each group to keep these intensity levels compact, for the purpose of performing equalized enhancement for targets. Experimental results demonstrate that the proposed method achieves better improvement on target-to-background contrast and better visual quality on targets by performing equalized enhancement for targets.

Urban residential consumers represent an increasing share in electricity consumption in Eastern China, making it vital for policy makers to understand how various factors, especially price, can impact residential power usage. This paper first introduces two micro-models for estimating electricity price elasticity. Based on data from a household survey in Shanghai and Nanjing, the electricity price elasticity in these two typical regions is calculated, which is approximately -0.51, or -0.68. Finally, the paper provides insights for policy makers regarding residential electricity market regulation in Eastern China.

Contact reed and contact subassembly are used in kinds of mechanical inertial apparatus, and they are is the media between electric signal and mechanical movement. In this paper, in accordance with the problem in the process of producing, through the experiment and analysis, the cause is found and processing technique to solving the problem is presented. The technique can be used in the producing process and can increase the passing rate of the gyroscope. The technique can play an important role in improving the overall assembly quality of the instrument and the ex-factory pass rate, effectively improving the reliability of spacecraft assembly.

An organic/silicon hybrid system is proposed for customizable Internet of Things (IoT) devices, composed of a silicon integrated circuit (IC) chip and organic field effect transistor (OFET) transducers. The silicon IC chip performs high performance and complex signal processing, and the OFET transducer provides flexible or conformable large area coverage and more friendly interfaces to integrate different sensing materials. A low trap-state density OFET (LTDOFET) technology is developed for such a hybrid system, owning features of low-cost solution printing processes, low operation voltage and excellent operational stability. This technology has been implemented with various materials, and processes, indicating its generality. Several sensor applications built based on this device technology are also reviewed, proving the LTDOFET technology would be promising for highly customizable IoT applications.

Based on the low-energy X-ray reference the (10-40)kV narrow-spectrum series of radiation masses are established, and the radiation field size and radiation field uniformity are measured. The results show that the field uniformity is better than 99% in all directions, and the radiation field range is about 50cm.The first half-value layer, the secend half-value layer and the homogeneity coefficient of the established radiation quality were measured and two scattered radiation experiments were carried out. Experiment 1 measures the air kerma rate at various points in the central axis of the X-ray beam. The results show that the dose rate satisfies the inverse square law and the smaller the tube voltage, the smaller the error. In experiment 2, the radiation field range was completely covered with lead with a thickness of 3 cm. The air kerma rate at various points in the central axis of the measurement showed that the effect of scattered radiation on the total dose rate did not exceed 2%. The X-ray energy spectrum of the subsurface under radiation was simulated by EGSnrc software, and the parameters such as average energy and resolution were calculated and compared with the national standard GB/T12162.1. The results show that the simulated radioactive energy spectrum is basically consistent with the national standard. The average energy and spectral resolution deviation is not more than 3%, and the established radiation quality meets the requirements.

Different mass R-290 (propane) leaked into the room from the inside and outside of a split type air conditioner indoor unit, and the refrigerant concentration was measured by infrared gas sensors. A CFD mode for RAC indoor unit including heat exchanger and fan was developed and verified by the test data. Through experiment and simulation, the dispersion characteristics of the refrigerant under different conditions were studied. The influence of installation height, leak point location, airflow rate and angle were tested and analyzed. Using velocity and concentration contours, jet camber resulted from leaked refrigerant and Coanda flow were illustrated clearly. The airflow volume at speed greater than 0.2 m/s could be applied directly to assess the effect of airflow on refrigerant mixing and diffusion.

A back-illuminated metal–insulator–semiconductor (MIS) structure AlGaN-based solar-blind ultraviolet photodiode is demonstrated for the purpose of overcoming the technical bottleneck caused by high Al content p-AlGaN in p–i–n structure. The device presents a peak responsivity of 0.115 A/W at 270 nm, corresponding to an external quantum efficiency (EQE) of 53% and an ultraviolet/visible rejection ratio of more than three orders of magnitude under zero-bias. Moreover, a response speed around 24 µs and a peak responsivity of 0.154 A/W, corresponding to an EQE of 70.6% will be achieved at a reverse bias of 3 V. The excellent performances of the back-illuminated MIS photodetector can be attributed to the adoption of a thin n-AlGaN layer of Al content gradient which plays a role of completely relaxing the strain of light absorption layer and the introduction of a homogeneous n-AlGaN interlayer into light absorption region which redistributes its electric field in favor of the separation and transport of the photo-generated carriers.

Integrating photovoltaic (PV) power into large-capacity hydropower plants is considered as an efficient and promising approach for large-scale PV power accommodation. To improve the guidelines for the optimal operation of large-scale hydro-PV hybrid systems, this paper proposes a practical coordination mode of a PV plant and a large-capacity hydropower plant based on the negotiation mechanism between the power generation company and the power grid. A chance-constrained programming (CCP) based stochastic optimization model is then presented to determine the short-term joint operation of a hydro-PV system, aiming at promoting renewable energy consumption. To improve the solution efficiency, several linearization approaches are proposed to convert the original model into a scenario-based mixed integer linear programming (MILP) problem. The real-world case studies demonstrate that the joint operation of the hydro-PV hybrid system can promote the consumption of renewable energy while making the actual total power output track the schedule submitted to the power grid. Moreover, the confidence level at which the power balance constraints can be met exceeds 90% in all weather conditions, far above the confidence level of less than 50% for the deterministic model, proving the stochastic model would be a better choice for the joint operation of a hydro-PV system.

Empirical mode decomposition (EMD) is a data-driven and multi-scale transform theory, and it is a nonlinear and non-stationary signal processing theory. But each EMD decomposition theory has its advantages and disadvantages. Synthetic aperture radar (SAR) imaging is an important remote sensing technique to obtain the change information, and SAR image data belongs to non-stationary signal. So EMD is very suitable for SAR image processing. There are two kinds of typical EMD theories, which are the ensemble empirical mode decomposition (EEMD) and bidimensional empirical mode decomposition (BEMD). Based on the deep study of the two methods, this paper proposed a new SAR image change detection algorithm, which is called the FCD-EMD algorithm, i.e. fusion change detection based on EMD. So FCD-EMD algorithm can obtain more accurate information, which not only includes the directional information obtained by EEMD, but also can contain the spatial information got by BEMD. The main contribution of the FCD-EMD algorithm is to fuse the detail information in different directions, so that the results obtained are more accurate than the individual method. On the other hand, it can reduce the influence of speckle noise in SAR images by feature selections. The actual SAR image data verify the algorithm proposed in this paper and good experimental results are obtained, which show that the new method is feasible.

Priority development of public transport is an important way to implement the sustainable development of urban transport, how to scientifically identify different travelers’ dependence on public transportation is conducive to explore the travelers' usage behavior of public transport, provide more accurate public transport services. Based on the dynamic and static data of public transport and individual travel survey data, this study uses the relevancy and matching technology to generate the individual travel chain information based on fused data, then selects 8 identification indicators from the dimensions of individual traveling habits behavior and individual attributes to describe the individual travel dependence on public transport. The two-step clustering algorithm which can deal with mixed variables is taken as an identification model of individual travel dependence on public transport. Finally, the identification model is applied to the actual research in Beijing, and the investigated population is clustered for four categories from the perspective of public transport travel dependence. Then the individual category of respondents is identified based on incomplete identification indicators, and the effects of assistant indicators on identification results are quantitatively evaluated with average hit ratio (AHR) and average coverage ratio (ACR). The results indicate that occupation, vehicle ownership, and income can be taken as assistant factors when the information of assistant indicators is incomplete and large scale of traveler data need to be collected and processed. The identification method of individual travel dependence on public transport can provide a meaningful reference for optimizing public transport system and improving public transport sharing rates.

Radiotherapy is an indispensable strategy for lung cancer, however, treatment failure or reoccurrence is often found in patients due to the developing radioresistance. Novel approaches are required for radiosensitizing to improve the therapeutic efficacy. In present study, we found that transglutaminase 2 (TG2) confers radioresistance in non-small cell lung cancer (NSCLC) cells through regulating TOPOIIα and promoting DNA repair. Our data showed that TG2 inhibitor or knockdown increased NSCLC radiosensitivity in vivo and in vitro. We found that TG2 translocated into nucleus and located to DSB sites, surprisingly, knockdown TG2 or glucosamine inhibited the phosphorylation of ATM, ATR and DNA-Pkcs. Through IP-MS assay and functional experiments, we identified that TOPOIIα as an downstream factor of TG2. Moreover, we found that TGase domain account for the interaction with TOPOIIα. Finally, we found that TG2 expression was correlated with poor survival in lung adenocarcinoma instead of squamous cell carcinoma. In conclusion, we demonstrated that inhibiting TG2 sensitize NSCLC to IR through interfere TOPOIIα mediated DNA repair, suggesting TG2 as a potential radiosensitizing target in NSCLC.

Radiation-induced lung injury (RILI) is a serious complication in thoracic tumour radiotherapy. It often occurs in clinical chest radiotherapy and acute whole-body irradiation (WBI) caused by nuclear accidents or nuclear weapon attack. Some radioprotective agents have been reported to exert protective effects when given prior to radiation exposure, however, there is no treatment strategy available for preventing RILI. In this study, we demonstrated that heat-killed Salmonella typhimurium (HKST), a co-agonist of Toll-like receptors 2 (TLR2), Toll-like receptors 4 (TLR4) and Toll-like receptors 5 (TLR5), mitigated radiation-induced lung injury through the transforming growth factor-β (TGF-β) signalling pathway. We found that HKST alleviated lung hyperaemia and pathological damage after irradiation, indicated that HKST inhibits the early inflammatory reaction of radiation-induced lung injury. Then, for the first time, we observed HKST reduced collagen deposit induced by irradiation in the later phase (7-14 week) of RILI, and we found that HKST inhibited radiation-induced cell apoptosis in lung tissues. We found that HKST reduced the level of TGF-β and regulated its downstream signalling pathway. Finally, it was found that HKST inhibited radiation-induced epithelial-mesenchymal transition (EMT) in lung tissues. In conclusion, our data showed that HKST effectively mitigated RILI through regulating TGF-β, provide novel treatment strategy for RILI in whole-body irradiation and radiotherapy.

The wide application of virtualization, big data, cloud storage and other technologies has made the data centralized storage increase security risks and leakage risks. For the problem of internal personnel using legal identity and role to steal internal information, this paper proposes a network information data protection architecture based on superposition encryption from the process of data generation, transmission, storage and processing. Based on the framework, including information storage protection based on symmetric cryptography and information transmission protection based on hybrid cryptography, a network information data protection scheme based on superimposed encryption is designed. Finally, the security of the scheme is proved.

In medical domain, given a medical question, it is difficult to manually select the most relevant information from a large number of search results. BioNLP 2019 proposes Question Answering (QA) task, which encourages the use of text mining technology to automatically judge whether a search result is an answer to the medical question. The main challenge of QA task is how to mine the semantic relation between question and answer. We propose BioBERT Transformer model to tackle this challenge, which applies Transformers to extract semantic relation between different words in questions and answers. Furthermore, BioBERT is utilized to encode medical domain-specific contextualized word representations. Our method has reached the accuracy of 76.24% and spearman of 17.12% on the BioNLP 2019 QA task.

The integrated operation of PV power plants and hydropower plants is regarded as an efficient and promising approach for large-scale PV power accommodation. This study mainly focuses on studying the optimal sizing of small and medium-sized hydro-PV systems, which are abundant in the northwest and southwest of China but are rarely considered by the existing researches. In this study, a scenario analysis technique, which includes typical scenario classification, the analysis of the inflow and PV power output under each scenario and scenario combination, is proposed to deal with the uncertainties of the inflow of the hydropower plant and the PV power output. On that basis, an optimization model is developed to determine the optimal size of a PV plant complementarily operating with a hydropower plant, where the hydro-PV hybrid system provides the baseload of local power grid and renewable energy curtailment is not allowed. A two-layer nested algorithm is then proposed to solve the model in a hierarchical structure. In the inner layer, an iterative trial calculation method for coupled dynamic programming is used to optimize the PV capacity for the given scenario. In the outer layer, the traversal search algorithm is employed to search for the optimal PV capacity in each scenario, and a confidence level accumulation method is proposed to determine the PV capacity for different confidence levels. The developed model and method are applied to the Naijili hydro-PV hybrid system which is located in Qinghai Province, China. Case studies demonstrate that the optimization of the PV capacity can significantly promote the consumption of renewable energy and effectively mitigate the adverse impact of PV output fluctuations on the power grids. The optimal PV capacities for different confidence levels are obtained, which can make it easy for planners to determine the installed capacity of the PV plant based on their own appetite for risk. Moreover, it is observed that, for small and medium-sized hydro-PV hybrid systems, the impact of capacity expansion of the hydropower plant on the solar energy consumption and the total power generation of the system is not significant.

In this paper, the electric field resonance (EFR) method, similar to the four-coil configuration of the magnetic field resonance wireless power transfer, is proposed for the capacitive coupling power transfer. The characteristics of the proposed method are derived and analyzed. With the EFR method, not only unity power factor for the power source is achieved, but also high power factor and low reactive power for the capacitive coupling stage are achieved. Effective power transfer is realized by the EFR method. Based on the proposed method, a dynamic charging concept for railway vehicles is then proposed. A prototype powering system is designed and built to prove the validity of the proposed method. Analytical, simulation, and experimental results are given and compared. A 23-cm model vehicle is put on a 150-cm track. It is shown that about 700-W power is transferred through a 24-pF coupling capacitor. The proposed method reaches 91% dc–dc overall efficiency at switching frequency 2 MHz.

For river-lake system, the riverbed topography and flow boundary are very complex. And it must meet small-scale and high-precision research requirement of navigable conditions. A plane 2D flow mathematical model is established for small- scale and large-range river-lake waterway system based on Mike21 software. It is validated by measured hydrological data. Then it is used to study the influence of the lake-control project on navigation conditions of the Dongting Lake. The results provide a scientific reference for the analysis of navigation benefits of the lake-control project.

Summary Double phase estimator (DPE) is an unambiguous binary offset carrier (BOC) tracking algorithm for band-limited receivers in Global Navigation Satellite Systems. Based on the strobe pulse method, the DPE was modified by introducing a strobe waveform in the prompt signal correlation process of the subcarrier phase lock loop in this paper.. This strobe DPE (SDPE) employs no additional correlators. Two different reference strobe waveforms and their receiving structures are provided. The performance of the SDPE is characterized according to the subcarrier multipath error envelope (SMEE) and the tracking jitter. Simulation results show that, relative to conventional DPE, the first waveform employed in this study provides a reduction in the SMEE area of 81.1% and 75.1% for BOC(1,1) and BOC(14,2) signal, respectively. The second waveform employed in this study provides a reduction in the SMEE area of 82.5% and 76.8% for BOC(1,1) and BOC(14,2) signal, respectively. They also both outperform the double estimator about 64.4% and 53.2% for BOC(1,1) and BOC(14,2) signal in the SMEE area. However, the SDPE experiences a loss of −6 and −7.25 dB, respectively, for two reference waveforms in terms of the post-coherent signal-to-noise ratio, which impacts its tracking precision. Copyright © 2016 John Wiley & Sons, Ltd.

A time-multiplexed double strobe scheme for unambiguous tracking of time-multiplexed binary offset carrier (TMBOC) modulated signal in GPS is presented. In the code tracking loop, two kinds of time-multiplexed strobe pulses are generated to track the BOC(1,1) and BOC(6,1) components, respectively. The strobe based on BOC(1,1) subcarrier eliminates the false lock points in the code discriminator, and the bump-jumping algorithm is not required. The other strobe employs the BOC(6,1) component to prevent additional signal-to-noise ratio loss. Thus, the proposed method simplifies the hardware structure in comparison with conventional strobe techniques, and improves the tracking performance in the presence of thermal noise and multipath.

Objective Patients receiving carbon-ion radiation therapy and astronauts exploring outer space are inevitably exposed to heavy ion radiation. The aim of this study was to develop radioprotectors to minimize the injuries induced by carbon ion radiation. Methods Heat-killed Salmonella Typhimurium (HKST) was administered to mice by gavage prior to irradiation with a 12C6+ heavy ion accelerator. Hematoxylin and eosin staining and immunofluorescence TdT-mediated dUTP Nick-End Labeling staining were used to assess the radioprotective effect of HKST on organ damage and levels of apoptosis, respectively, in mice. To investigate the mechanism underlying the radioprotective effect of HKST, levels of the pro-apoptotic proteins BAX and caspase 3 as well as interferon-regulatory factor (IRF) 3/7 in the femur, testis and intestine were assessed using immunofluorescence. Results Injuries induced by carbon ion radiation were significantly eased by pretreatment with HKST. Both apoptosis and high expression levels of pro-apoptotic proteins induced by heavy ion radiation were inhibited by HKST pretreatment. The radioprotective effect of HKST was associated with stimulation of Toll-like receptor signaling mediated by enhanced IRF3 and IRF7 signaling. Conclusion HKST was an effective radioprotector alleviating damage to multiple organs caused by heavy ion radiation.

Spacecraft antenna is an antenna loaded on the spacecraft and an indispensable part of the spacecraft system. It is particularly important to measure the assembly accuracy of the antenna. A certain type of satellite needs to test the amplitude of antenna A and B in sinusoidal vibration test. Because the distance between antenna A and antenna B is very close to the fairing, it is necessary to measure the amplitude of antenna A to verify the spatial compatibility of antenna A with carrier fairing and antenna B in the test process. By comparing four kinds of antenna measurement technology, this paper chooses high-speed photography technology to measure the amplitude of the antenna, uses recognition processing computing technology to binarize the image, changes the image into calculable coordinate value, obtains the amplitude data of X-direction and Y-direction, and verifies the space composite compatibility requirements between antenna A, carrier fairing and antenna B under vibration conditions. There will be interference and collision.

In this study, a geometric model of Wolter-I X-ray focusing mirror was established, and a set of equations were derived for determining the parameters of glass substrate focusing mirror. In order to study the focal spot diffusion at the theoretical focal point under the condition of point light source. A formula for calculating the focal spot size of the single-layer focusing mirror at the theoretical focal length under point-source incident light was derived through theoretical analysis. A set of Wolter-I X-ray focusing mirror were fabricated through a slumping process using Schott D263 T glass,which is designed based on the derived equations. Ray tracing software was used to simulate the size variations of focal spot under parallel incident light and point-source incident light. A test system was constructed, and experiments were conducted to verify the validity of the calculation formula and the results of the simulation analysis. The test results showed that the theoretical results are in good agreement with the experimental results.

The problems of quality and safety in AIT (assembly Integration and test), especially the damage of the crucial equipment or key parts, will have a great impact on quality, schedule, and cost of the spacecraft development process. Therefore, an engineering method of risk identification and prevention to evaluate the safety of key process in AIT is needed in order to improve the safety risk control ability for spacecraft. In this paper, we use the fuzzy comprehensive evaluation and analytic hierarchy process (AHP) method to construct the spacecraft assembly safety evaluation model. Based on the expert scoring, combining the multilevel fuzzy comprehensive evaluation method and directly scoring method, the weights of each evaluation index are analyzed and determined. After calculation, the risk value of the key activities for the spacecraft assembly process is obtained. The verification work on a certain type of spacecraft shows good effect that the assessment results accord with experience well and have high degree of distinction.

According to the demands of an array detector in the X-ray pulsar navigation system for Micro-channel Plate (MCP), a selection method for the MCP was explored. Four key parameters for the selection of MCPs, the uniformity of gain, impedance matching, dark count rate and the gain coefficient were determined. Based on the four key parameters, corresponding experiments were designed and the selection process of MCPs was set out. The amplitudes and counting rates of MCPs selected by proposed method were tested. The tested results show that the relative error of each detection unit is not identical. When a single channel anode is used, the ranges of the maximum relative error Δ1i and minimum relative error Δ2i of the amplitudes for output signals from the ith anode are 7%-13.5% and 3%-6.7%, respectively, and when a four-channel anode is used, Δ1i and Δ2i are 7.8% and 3.1%, respectively. Moreover, the relative error between the anode count rate n1+n2+n3+n4 from the single channel and N from the four-channel shared anode is 4.38%, less than 10%. Obtained results indicate that the MCPs with good performance have been effectively chosen by the proposed selection method. ©, 2015, Chinese Academy of Sciences. All right reserved.

With the rapid development of Internet technologies such as cloud computing and big data, the scales of distributed information systems in big companies have grown to enormous sizes. Automatic detection and diagnosis of system faults in the large-scale information systems is complicated and important in both practice and research. In this paper, we propose a Graph-based Fault Diagnosis approach in Distributed System (G-FDDS), in which availability testing records of distributed systems are represented by a multi-relational graph in order to find out latent root causes of the failures of availability testing. Vertices represent non-repeated failed availability testing records and edges indicate multiple relations between these records, then a clustering method is proposed to group similar vertices into fault causes. Our approach is more appropriate for mining accurate fault causes both in the simulation and real datasets comparing with other commonly used methods such as statistical methods.

// Jiaming Guo 1, * , Yuanyuan Chen 1, * , Xiao Lei 1, * , Yang Xu 1 , Zhe Liu 1 , Jianming Cai 1 , Fu Gao 1 and Yanyong Yang 1 1 Department of Radiation Medicine, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, P.R. China * These authors have contributed equally to this work Correspondence to: Yanyong Yang, email: yyyang2010@163.com Fu Gao, email: gaofusmmu@163.com Jianming Cai, email: cjm882003@163.com Keywords: monophosphoryl lipid a (MPLA), radioprotection, toll like receptor 4 (TLR4), TRIF, MyD88 Received: June 16, 2017 Accepted: August 04, 2017 Published: September 15, 2017 ABSTRACT Ionizing radiation causes severe damage to human body, and normal tissue toxicity in cancer radiotherapy also limits its further application. It is urgently required to develop safe and effective radioprotector. Our previous study has shown that toll like receptor 4 (TLR4) was dispensable for basal radiation resistance. However, severe toxicity of its traditional agonist lipopolysaccharide limits the clinical application. In present study, we demonstrated that monophosphoryl lipid A (MPLA), a potent TLR4 agonist with low toxicity, effectively attenuated radiation injury on in vitro and in vivo . MPLA increased cell survival and inhibited cell apoptosis after irradiation, and cell cycle arrest was also inhibited. Radiosensitive tissues including spleen, intestine, bone marrow and testis were protected from radiation damages in a TLR4 dependent manner. We also found that myeloid differentiation factor 88 (MyD88) accounted more than Toll/IL-1R domain-containing adaptor inducing IFN-β (TRIF) for the radioprotective effects of MPLA. In conclusion, our finding suggests TLR4 agonist MPLA as a safe and effective radioprotector for clinical application.

In this paper, a novel +45° insulator is proposed. The insulator has a conductivity graded structure in which the high conductivity part performs as a shield to reduce the electric field concentration at anode triple point and along surface. Hence, the surface electrical withstanding strength would be enhanced. Computer aided simulation is performed to investigate the electric field distribution with different shape parameters of high-conductivity area and an electric field optimized insulator design is thus obtained. A Fused Deposition Modeling 3D printing technique is adopted to fabricate the conductivity graded insulator. The wide application of 3D printing in insulator fabrication is expected for its ability to fabricate special functional structure and high fabricating efficiency. Flashover tests are to be conducted to investigate the electrical withstanding performance of such insulators.

Flexible accessories is an important part of modern satellite, the elastic vibration is the main factor influencing the control performance of space vehicle, which make it necessary to test the performance of vibration suppression for the control system on the ground. The difficulty of physical simulation is to simulate the space microgravity environment, the length of solar array is large and frequency is low, which make it extremely difficult to build the space microgravity environment. In view of the above situation, this paper proposes a method of flexible solar simulator based on air flotation, and we design the physical simulation system based on equivalent spindle inertia and flexible frequency. Dynamic model is established for the simulation system to make sure that the system can equivalently simulate the torque characteristics of flexible satellite rotating panels, which reduces the difficulty to simulate ground microgravity environment. The rationality of the scheme is verified by the simulation results, whose results show that, the simulator has torque characteristics consistent with real solar panels, and we can achieve a smooth change of parameters by a simple operation to simulate different parameters and structure of the solar array. This method meets the test requirements and can effectively and efficiently examine the vibration performance of the control algorithm.

At present, preceding vehicle detection remains a challenging problem for autonomous vehicle technologies. In recent years, deep learning has been shown to be successful for vehicle detection, such as the faster region with a convolutional neural network (Faster R-CNN). However, when the host vehicle speed increases or there is an occlusion in front, the performance of the Faster R-CNN algorithm usually degrades. To obtain better performance on preceding vehicle detection when the speed of the host vehicle changes, a speed classification random anchor (SCRA) method is proposed. The reasons for degraded detection accuracy when the host vehicle speed increases are analyzed, and the factor of vehicle speed is introduced to redesign the anchors. Redesigned anchors can adapt to changes of the preceding vehicle size rule when the host vehicle speed increases. Furthermore, to achieve better performance on occluded vehicles, a Q-square penalty coefficient (Q-SPC) method is proposed to optimize the Faster R-CNN algorithm. The experimental validation results show that compared with the Faster R-CNN algorithm, the SCRA and Q-SPC methods have certain significance for improving preceding vehicle detection accuracy.

X-ray focusing telescope is one of the most important equipment for X-ray space observation, which is designed based on the grazing incidence principle. The purpose of x-ray observation is to detect the black holes of various sizes in outer space, and the data obtained by X-ray telescope conduces to investigating the basic physical law under the condition of extreme gravity and magnetic field, In this article, multi-layer telescope is designed to satisfy the demand for enhanced X-ray timing and polarimetry mission. in which the telescope is designed based on Wolter-I telescope. The Monte Carlo method and power spectral density are used when the relationship between mirror profile and roughness with angular resolution is investigated. We analyze the relationship between angular resolution and mirror profile, and the result shows that the higher mirror profile possesses higher angular resolution. When the root mean square(RMS) of mirror profile is 0.04 μm, PV is 0.2 μm and roughness is 0.4 nm, the mirror angular resolution is 6.3" and it will change to 30.6" when the RMS of mirror profile is 0.2 μm, PV is 1 μm and roughness is 0.4 nm. The angular resolution out of focus is also investigated in this article, and the more defocusing amount gives rise to the worse angular resolution because defocusing spot will be larger than that of focal plane. So the maximum defocusing amount of 5 mm is required when the focal plane detector is installed. The relationship between effective area with film structure and layers number is also investigated. The film with Au mixed with C has a higher reflectivity than the film with only Au, because the mixed film will generate an interference effect and enhance the intensity of reflecting X-ray. When the telescope layers increase, the effective area and telescope weight are both improved, the requirement for effective area of satellite can be satisfied when the number of nesting layers is 45. However, when the number of nesting layers further increase, the effective area will be improved with a low speed, but the weight of telescope will increase with a high speed. The field of view of this telescope is 16′, which is more than the required value of 12′. Finally, the X-ray focusing telescope with 5.25 m focal length, 45 nesting layers, effective area 842 cm2 at 2 keV, 563 cm2 at 6 keV is obtained.

The time-domain modified recursive least squares (MRLS) online parameter identification algorithms' accuracy and robustness have been verified through a small fixed-wing UAV flight test. The frequency domain least-squares (FLS) online parameter identification algorithm has also been tested, and is compared with the time-domain method. The flight test results show that with sufficient active excitation, these two types of online parameter identification algorithms are able to perform the system parameters identification accurately, even using low-cost sensors (MEMS Inertial Measurement Unit, and noisy wind vanes). A single iteration of the running time of the time-domain modified recursive least-squares (MRLS) on a low-cost arm chip takes less than 0.5ms, meeting the real-time requirements. The frequency-domain least-squares (FLS) algorithm takes slightly larger amount of time, but the convergence course is similar to time-domain algorithm. The verification of the online parameter identification algorithm via flight test provides technical foundations of the fault tolerance control system.

Tandem solar cells comprised of a III-V material on Si offer a path to efficiencies exceeding 30%. The four-terminal architecture, in which each of the two sub-cells is electrically independent, allows for especially high energy yields, as it is not limited by current-matching. Each sub-cells' contacts cause optical and electrical losses, however; and a careful optimization is required to exploit the full potential of this architecture. In this study, we explore the potential efficiency gains of an example 21.3% GaAs-on-Si four-terminal tandem [1] by re-designing the metal grid contact geometry. We optimize and model the contact losses and predict a potential efficiency increase of 3.4%. We demonstrate the importance of careful metal grid design and the benefits of using energy yield as a figure of merit when design contacts for a practical 4T tandem subject to realistic operating conditions.

Automaton-based pattern matching methods have been widely used in security services for traffic inspection and filtering. However, a large scale of patterns may be updated frequently in a multi-tenant cloud, which poses new challenges to avoid attacks while updating new patterns. This paper presents an agile approach named Eagle for "on-the-fly" updating automaton in cloud security services. The approach provides three algorithms on AC and SBOM, adding, deleting and updating operation, to update state and links of automaton in high-speed online cloud traffic. Theoretical analysis shows that Eagle lowers the computational complexity of updating patterns from O (n2) to O (n). The effectiveness of this agile approach is verified when applied to a real cloud gateway. It turns out that 68% - 89% of the time can be saved and the throughput of cloud traffic filtering proves no reduction during and after the pattern update.

According to the requirement for cables tridimensional layout in spacecraft, the research on new transmission line support (NTLS) is carried out. NTLS is namely T support. Based on the analysis of NTLS's physical parameters, the scheme of cable installing is established. Experimentations of statics and vibration prove the feasibility and dependability of the scheme. The results of experimentation indicate that the scheme of cable installing on T support is reasonable along with the requirement of cables tridimensional layout is satisfied. Therefore the efficiency of spacecraft assembly and integration is greatly enhanced.