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Recently, the outbreak of the infection of Duck adenovirus 3 (DAdV-3) characterized by swelling and hemorrhagic liver and kidney has caused huge economic losses to duck industry since 2014 in China. To date, the B cell epitopes in the Fiber-1 protein and the underlying infection mechanism of DAdV-3 have not been investigated. In this study, the recombinant Fiber-1 protein was first expressed in E. coli and six novel monoclonal antibodies (mAbs) against Fiber-1 were generated, designated as 1D8, 1E6, 3G6, 4G1, 4G2, and 6F10, respectively. Moreover, mAbs 3G6 and 6F10 could efficiently immunoprecipitate the Fiber-1 in LMH cells infected with DAdV-3 or transfected with pcDNA3.1-Fiber-1. Notably, mAbs 3G6 and 4G2 also showed certain neutralizing activity against DAdV-3 infection in vitro. Epitopes mapping revealed that the B cell epitope recognized by 6F10, 3G6, 4G1, 1D8, 4G2, and 1E6 was located in 34-66aa, 67-99aa, 64-296aa, 297-329aa, 330-362aa, and 363-395aa, respectively. Sequence alignments further found that the six epitopes recognized by these mAbs were highly conserved among different DAdV-3 isolates. The generated mAbs specific to Fiber-1 and their defined epitopes provide powerful tools for establishing rapid and efficient diagnostics for the detection of DAdV-3 and pave the way for further studying on the critical role of Fiber-1 in mediating the infection of DAdV-3.

Intelligent munition, which integrates networking, big data, deep learning and other artificial intelligence (AI) technologies, is increasingly become the key to military reforms and combats in the future. Therefore, this study defines the connotations and features of intelligent air-to-ground precision strike munition, and provides an analysis on the development status and trend of such munition at home and abroad from the aspects of single intelligence and swarm intelligence. By drawing experience from the development of the U.S. army, this paper elaborates on the ways of establishing the technological system of intelligent air-to-ground precision strike munition from three aspects, namely, single intelligent technology, system integration and operational application. The study is expected to promote the research and development of the next generation of air-to-ground precision strike munition with intelligent features including perception, learning, decision-making and collaboration.

Intelligent manufacturing is a new mode and trend of sustainable manufacturing development. It optimizes the design and manufacturing process of products and greatly reduces the consumption of resources and energy by virtue of the huge potential of computer modeling and simulation and information communication technology. Under the background of intelligent manufacturing, intelligent bearing is proposed on the basis of traditional bearing products. Intelligent bearing is one of the research and development directions of high-end bearings at home and abroad. Embedded test technology is one of the research fields of intelligent bearings at present. Firstly, based on the finite element model, the structural design problems related to the integration of rolling bearing and sensor are studied. According to the load distribution of bearing, the optimal slot position of bearing is determined. Considering the influence of reducing the bearing capacity, the influence of axial and radial slot ways of bearing outer ring on the maximum deformation and stress of bearing outer ring is studied, and the bearing outer ring is analyzed The relationship between the maximum deformation, maximum stress and the groove size of the outer ring of the bearing is determined to provide the basis for the selection and design of the sensor module. Secondly, according to the friction moment formula, the total heat of the bearing is calculated. Based on the workbench, the temperature field cloud distribution model of the rolling bearing is established to analyze the changes of the speed, the radial load and the temperature of the inner and outer ring of the bearing Finally, according to the slot position and slot size, select the appropriate sensor and rolling bearing integration to achieve the real-time monitoring of the operation state of the bearing.

In this article, a multiple diffuse coding metasurface (MDCM) of independent polarization is designed to control the propagation direction of diffuse reflections under different polarizations and to improve the monostatic and bistatic RCS (radar cross section) reduction effect. First, a method for controlling the distribution range and propagation direction of the diffuse field is studied, and the diffuse field distribution of the random phase metasurface is optimized by a genetic algorithm to improve the uniformity of the diffuse scattering distribution. Then, the random phase distribution is superimposed on the periodic gradient phase distributions of the linear and hedge types in the orthogonal direction so that the main propagation direction of the diffuse metasurface deviates from the specular reflection region under different polarizations, showing single and two diffuse beams. Finally, the anisotropic unit cell with a rectangle inside and an improved Jerusalem cross on the outside is employed as the basic coding element of the MDCM due to its independent polarization phase response. The numerical and experimental results show that the MDCM features multiple diffuse scattering, independent polarization and angle insensitivity and can efficiently improve the monostatic and bistatic RCS reduction effect simultaneously. Because the scattered energies are redirected away from the specular reflection direction, the specular scattering reduction effect is better than the isotropic diffuse metasurface. The proposed method increases the difficulty of detection by single or netted radar and has the potential for the applications of stealth techniques.

For fully-air-processed perovskite solar cells (PSCs), high-quality perovskite films and improved intrinsic stability are critical for high photovoltaic performance. However, strain, as a critical factor of perovskite instability, not only harms the efficiency of PSCs but also accelerates the degradation of the PSCs devices. In this report, we introduce a novel negative thermal expansion (NTE) material into perovskite film for the first time, growing a high-quality perovskite films with high crystallinity, large grain size and low defect density. More importantly, effective residual strain relaxation of perovskite films is achieved, the thermal expansion compensation properties of NTE materials reduces the overall thermal expansion coefficient for perovskite films. As a result, the fully-air processed PSC achieves a champion power conversion efficiency (PCE) of 22.40 %. Simultaneously, the unencapsulated device retains 93.78 % of its original PCE after storage in ambient air after 90 days. Furthermore, these devices also show excellent thermal stability and remarkable light stability. The present study not only provides insights into the multi role of NTE materials, but also provides a new path for the application of NTE materials in the photovoltaic field.

Background: Cardiac surgery is associated with a substantial risk of major adverse events. Although carbon dioxide (CO2)-derived variables such as venous-to-arterial CO2 difference (ΔPCO2), and PCO2 gap to arterial–venous O2 content difference ratio (ΔPCO2/C(a−cv)O2) have been successfully used to predict the prognosis of non-cardiac surgery, their prognostic value after cardiopulmonary bypass (CPB) remains controversial. This hospital-based study explored the relationship between ΔPCO2, ΔPCO2/C(a−cv)O2 and organ dysfunction after CPB.Methods: We prospectively enrolled 114 intensive care unit patients after elective cardiac surgery with CPB. Patients were divided into the organ dysfunction group (OI) and non-organ dysfunction group (n-OI) depending on whether organ dysfunction occurred or not at 48 h after CPB. ΔPCO2 was defined as the difference between central venous and arterial CO2 partial pressure.Results: The OI group has 37 (32.5%) patients, 27 of which (23.7%) had one organ dysfunction and 10 (8.8%) had two or more organ dysfunctions. No statistical significance was found (P = 0.84) for ΔPCO2 in the n-OI group at intensive care unit (ICU) admission (9.0, 7.0–11.0 mmHg), and at 4 (9.0, 7.0–11.0 mmHg), 8 (9.0, 7.0–11.0 mmHg), and 12 h post admission (9.0, 7.0–11.0 mmHg). In the OI group, ΔPCO2 also showed the same trend [ICU admission (9.0, 8.0–12.8 mmHg) and 4 (10.0, 7.0–11.0 mmHg), 8 (10.0, 8.5–12.5 mmHg), and 12 h post admission (9.0, 7.3–11.0 mmHg), P = 0.37]. No statistical difference was found for ΔPCO2/C(a−cv)O2 in the n-OI group (P = 0.46) and OI group (P = 0.39). No difference was detected in ΔPCO2, ΔPCO2/C(a−cv)O2 between groups during the first 12 h after admission (P > 0.05). Subgroup analysis of the patients with two or more failing organs compared to the n-OI group showed that the predictive performance of lactate and Base excess (BE) improved, but not of ΔPCO2 and ΔPCO2/C(a−cv)O2. Regression analysis showed that the BE at 8 h after admission (odds ratio = 1.37, 95%CI: 1.08–1.74, P = 0.009) was a risk factor for organ dysfunction 48 h after CBP.Conclusion : ΔPCO2 and ΔPCO2/C(a−cv)O2 cannot be used as reliable indicators to predict the occurrence of organ dysfunction at 48 h after CBP due to the pathophysiological process that occurs after CBP.

During the operation of the fracturing pump, the friction between the sliding shoe and the guiding plate generates heat, which can rise the temperature of the friction surface, causing the fracturing pump to fail. Generally, relying only on worker experience to adjust the gap between the guiding plate and the sliding shoe and determine the oil supply flow lacks scientific basis and theoretical guidance, which may result in sliding shoe and guiding plate wear, and the increasing probability of burning tile. It seriously shortens the service life of the fracturing pump and affects the safe production of fracturing operations. Therefore, this paper studies the frictional heat generation and heat dissipation mechanism of the sliding shoe and guiding plate. After deriving the formula, a model for the influence of the gap of the sliding shoe and the guiding plate and the oil supply flow rate on the temperature rising of lubricating oil is established. And the test validation was carried out on the experimental platform of 6000 HP fracturing pump. The results showed that the change of temperature rise of the lubricating oil is more obvious as the gap decreases. When the gap between the sliding shoe and the guiding plate is less than 0.2 mm, the temperature of the lubricating oil reaches 360 K, which has exceeded the allowable working temperature of the selected lubricating oil. An increase in the flow rate of the lubricating oil can lower the temperature of the lubricating oil; however, when the flow rate of the lubricating oil exceeds 2 L/min, the effect on the temperature rise of the lubricating oil is not significant. In this study, a lubrication cooling state model for fracturing pump calibration was proposed. It provides a theoretical basis and design reference for reasonable selection of lubricating oil supply flow and the gap.

Millions of geo-tagged photos are becoming available due to the wide spread of photo-sharing websites, which provide valuable information to mine spatial patterns from human activities. In this study, we present a simple and fast density-based spatial clustering algorithm to detect popular scenic spots using geo-tagged photos collected from Flickr. In this algorithm, Gaussian kernel is applied to estimate local density of data points, and a decision graph is used to obtain cluster centers easily. More than 289,000 geo-tagged photos located in five typical cities of China are downloaded as case studies, and data pre-processing such as duplicate removing is performed to improve the quality of clustering result. Finally, popular tourist attractions of each sample city are successfully detected with this algorithm, and our result is useful for recommending some interesting destinations which might not be on the list of tourist website or mobile guide applications. The proposed solution is robust with respect to different distributions of photos, and it is efficient by comparing with other popular clustering approaches.

Superinductors are inductors whose microwave characteristic impedances are greater than the resistance quantum, $R_{Q}=h/(2e)^{2}approx6.5kOmega$. They can be implemented using Josephson junction chains and high kinetic inductance nanowires. In this dissertation, we explore applications of superinductors in both implementations in superconducting quantum circuits. The dissertation consists of three parts. In the first part, we discuss the fluxon-parity-protected qubit consisting of a Cooper-pair box (CPB) shunted by a superinductor made of a chain of coupled asymmetric Superconducting Quantum Interference Devices (CASQUIDs). The spectroscopic measurement of a prototype of the fluxon-parity-protected qubit was performed. We observed almost complete suppression of the single fluxon tunneling across the CPB due to the destructive Aharonov-Casher interference when the offset charge on the CPB island was set to $e$ mod(2$e$). A fluxon-parity-protected qubit with a higher superinductance can potentially be used to perform fault-tolerant Clifford gates. In the second part, we studied the microwave losses in high-kinetic-inductance granular Aluminum films using superconducting coplanar-waveguide (CPW) resonators made of the films. We observed that the intrinsic losses in these resonators at low temperatures were limited by resonator coupling to the two-level systems (TLS) in the environment. The demonstrated internal quality factors are comparable with those for CPW resonators made of conventional superconductors. The characterized granular Aluminum films can be used to fabricate superinductors for a wide range of applications in quantum metrology and quantum information processing. In the third part, we discuss the one-dimensional Josephson metamaterial made of a similar structure as the superinductor used in the fluxon-parity-protected qubit. The metamaterial demonstrated strong Kerr nonlinearity with the Kerr constant tunable over a wide range from positive to negative values by the magnetic field. The metamaterial is promising for use as an active medium for quantum-limited Josephson traveling-wave parametric amplifiers.

The design of inlet into S-shaped is a stealth method with limited effect. The ICP generated in closed quartz chamber is an effective solution to improve the stealth effect. In this paper, an inductively coupled plasma (ICP) generator with the size of 30cm×30cm×2cm which could be conformal with S-shaped inlet was designed, the discharge experiment was carried out to study the discharge configuration of air ICP and the distribution of the electron density in the core area of ICP under 100Pa and different discharge power was diagnosed with microwave interference method. On this basis, the three-dimensional electromagnetic model of inlet and the plasma generator were established and the finite-difference time-domain method was used to calculate the broad-band scattering parameter of the inlet with and without the ICP generator. The variation of radar cross section area (RCS) with the azimuth angle, electromagnetic wave frequency and discharge power of ICP was studied. The result indicated that the ICP generator could effectively improve the stealth effect of S-shaped inlet in the head direction.

Identifiable signatures about people can be left automatically and unobtrusively when they are using smartphones, which can help to identify different users and offer personalized service to them. Specifically, offering services to users according to their age is significant and necessary, as people with different ages have distinct requirements for phone use. However, the smartphone knows little about the user's age. In this paper, we introduce CHIP, a system that achieves CHildren user Identification based on smartphone sensory data only. The system first captures data in two scenes, i.e., unlocking screen and phone answering, by utilizing ubiquitous sensors available in commodity mobile phone. Based on these scenes, we then extract features in the stages of picking up the phone, swiping the screen, response time, and answering the phone. The Random Forest classifier is further used to identify children users. We evaluate the system through real-life experiments conducted by 8396 effective samples from 35 participants with different ages. Experimental results show that our approach achieves the precision of 94.80% in identifying children phone users.

Four custom fiber Bragg grating (FBG)-based sensors are developed to monitor an artificial landslide located in Nanjing, China. The sensors are composed of a rod and two FBGs. Based on the strength of the rods, two sensors are referred to as “hard sensors” (Sensor 1 and Sensor 2), the other two are referred to as “soft sensors” (Sensor 3 and Sensor 4). The two FBGs are fixed on each sensor rod at distances of 50 cm and 100 cm from the top of the rod (an upper FBG and a lower FBG). In the experiment presented in this paper, the sensors are installed on a slope on which an artificial landslide is generated through both machine-based and manual excavation. The fiber sensing system consists of the four custom FBG-based sensors, optical fiber, a static fiber grating demodulation instrument (SM125), and a PC with the necessary software. Experimental data was collected in the presence of an artificial landslide, and the results show that the lower FBGs are more sensitive than the upper FBGs for all four of the custom sensors. It was also found that Sensor 2 and Sensor 4 are more capable of monitoring small-scale landslides than Sensor 1 and Sensor 3, and this is mainly due to their placement location with respect to the landslide. The stronger rods used in the hard sensors make them more adaptable to the harsh environments of large landslides. Thus, hard sensors should be fixed near the landslide, while soft sensors should be placed farther away from the landslide. In addition, a clear tendency of strain variation can be detected by the soft sensors, which can be used to predict landslides and raise a hazard alarm.

Making use of the features of radial distribution systems, a chromosome coding method and genetic operation strategies were developed. Crossover operations were defined as to exchange the same template while mutation operations and inversion operations are restricted in the template. The above strategies greatly reduce the infeasible solutions produced during genetic operations. Further, a simplifying power distribution method was also proposed to reduce the length of chromosome and reciprocal value of the active power losses as the fitness function. The above measures improve the performance of genetic algorithms for distribution reconfiguration. Several tests were conducted and the results have shown that the proposed algorithm has advantages over other previously developed algorithms.

A differentiating/integrating (D/I) system which does not change GIS (gas insulated substation) configuration is developed for the measurement of very fast transient overvoltages (VFTO) occurring in GIS. Then the numerical computation of VFTO is studied on the base of field measurement results. Some factors influencing VFTO magnitude are analyzed through computation. The possible reason why VFTO may cause more failures in 300 kV and above GIS is presented.

Q-learning can provide a robust and natural means for agents to learn how to coordinate their action choices in multi-agent systems. We examine some of the factors that can influence the dynamics of the learning process in such a setting. We first distinguish reinforcement learners that are unaware of (or ignore) the presence of other agents from those that explicitly attempt to learn the value of joint actions and the strategies of their counterparts. We study Q-learning in cooperative multi-agent systems under these two perspectives, focusing on the convergence to Nash equilibrium. We propose an exploration strategy to increase the likelihood of convergence to an optimal equilibrium.

It is well known that spark conditioning is the simplest and most effective method to raise the breakdown voltage. This paper describes the effect of spark conditioning with a parallel capacitor on trapping various impurities and absorbed layer of gases during pumping out a vacuum switch. Results show that with a suitable capacitor parallel to the vacuum switch, the breakdown energy may be high enough to make the electrode surfaces locally melted and rapidly cooled, which will form a fine grained layer. Also, increasing the number of breakdowns in a unit time and breakdown energy will be an effective method for manufacturing vacuum switches.

Defect passivation has been recognized as an effective strategy to improve efficiency and stability of perovskite solar cells (PSCs). In this work, in-depth theoretical calculations and experimental characterizations reveal the dual-site synergistic passivation of 1H-benzimidazole (BIZ), and the conjugated structure of the benzene ring tends to increase the interaction between BIZ and perovskite. High-quality perovskite films are thus achieved, with increased grain size, reduced defect density, and suppressed ion migration. Simultaneously, the reduced work function and optimized band alignment promote carrier transport, reducing nonradiative recombination, and loss of open-circuit voltages, as well as fill factor. Consequently, the target PSC devices achieve a champion power conversion efficiency (PCE) of 24.59%, and 20.49% for perovskite solar module (a designated area of 27.5 cm(2)). The unencapsulated PSC maintains 91.49% of original PCE after storing in air with an average relative humidity of 40% for 2400 h. Moreover, the device exhibits remarkable the long-term operational stability, maintaining 90.47% of initial PCE after continuously operating at the maximum power point for 1000 h. This study not only provides insights into the synergistic passivation of BIZ but also provides a strategy for the application of BIZ derivatives in the photovoltaic field.