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Accurately localizing the pupil is an essential requirement of some new human–computer interaction methods. In the past, a lot of work has been done to solve the pupil localization problem based on the appearance characteristics of the eye, but these methods are often specific to the scenario. In this paper, we propose an improved U-net network to solve the pupil location problem. This network uses the attention mechanism to automatically select the contribution of coded and uncoded features in the model during the skip connection stage of the U-net network in the channel and spatial axis. It can make full use of the two features of the model in the decoding stage, which is beneficial for improving the performance of the model. By comparing the sequential channel attention module and spatial attention module, average pooling and maximum pooling operations, and different attention mechanisms, the model was finally determined and validated on two public data sets, which proves the validity of the proposed model.

Remote mountainous areas have complex terrain, so the information transmission capacity of communication links have been greatly restricted. In addition, the maritime areas have the problem of limited communication base stations and limited communication links as well. Currently, the most commonly used air-based platforms for spectrum forwarding, which only support a small coverage of areas, fail to achieve wide-area or cross-regional signal connectivity, and only support a limited number of concurrent users. Therefore, this paper proposes an integrated communication enhanced link based on frequency detection, conversion and forwarding, which solves the problem that information sharing is not stable. And the simulation results verify that the proposed integrated communication enhanced link addresses the problem of multiple users (up to 150) to communicate concurrently in a cross-region area (radius 50 km) which may have mountains in between. And also, the proposed air-based platform only requires a low power of energy, so that the platform can work longer time in the air.

As programing became more and more important, people are taking a large amount of work to help students to learn programming skills effectively. This paper applies a programming learning game called May's Journey to fit 5 debugging types including syntax, logical, structure, reasoning, and undefined debugging errors into programming levels. Then we can find out the reason why students make mistakes, and which debugging type would cause the mistakes of other debugging types. And we have 6 findings, (1) This paper proposes a student debugging model to describe how students make debugging errors, which is used for further analysis on student debugging behaviors. (2) This paper proposes to use group mean and with-in group variance based on student debugging model, which finds out the common debugging errors and personal debugging errors. (3) This paper proposes to extract student debugging patterns using Random forest, which identifies student debugging behaviors, so that students who have the same debugging pattern can be trained together. (4) This paper also proposes to use student debugging model-based SVM to extract student performance patterns, which identifies student performance changing over programming levels in terms of a specific debugging type. (5) This paper proposes to apply mean decrease accuracy and mean decrease Gini to identify the effectiveness of debugging types; and (6) this paper proposes to use a classification-based LSTM algorithm to predict debugging errors, which improves the predication accuracy a lot. Experiments and results are also provided to prove that our methods are valid and better.

With the continuous innovation of optical remote sensing technology and the increasing demand for spatial information, satellite videos, which can provide higher spatial and temporal resolution, have been paid a lot of attention. And moving vehicles extraction in satellite videos is one of the most important tasks. By analyzing the shortcomings of current satellite video moving vehicles extraction algorithms, and combining with the characteristics of satellite videos and moving vehicles, this paper proposes an algorithm to extract moving vehicles in satellite videos, that some vehicles are firstly separated from the background by using image extreme points and mean differences, and then the moving vehicles are extracted by joint detection of inter-frame vehicles motion. At the same time, based on the extracted moving vehicles, we also propose a method that can extract road masks by using only three frames. Finally, we use Jilin-1 satellite video data to prove the proposed methods in the experiment. And also this paper has compared the propose methods with another two algorithms, where the results show that the proposed methods greatly improve the accuracy and quality of moving vehicles detection in satellite videos.

PBRM1 is the second most commonly mutated gene after VHL in clear cell renal cell carcinoma (ccRCC). However, the biological consequences of PBRM1 mutations for kidney tumorigenesis are unknown. Here, we find that kidney-specific deletion of Vhl and Pbrm1, but not either gene alone, results in bilateral, multifocal, transplantable clear cell kidney cancers. PBRM1 loss amplified the transcriptional outputs of HIF1 and STAT3 incurred by Vhl deficiency. Analysis of mouse and human ccRCC revealed convergence on mTOR activation, representing the third driver event after genetic inactivation of VHL and PBRM1. Our study reports a physiological preclinical ccRCC mouse model that recapitulates somatic mutations in human ccRCC and provides mechanistic and therapeutic insights into PBRM1 mutated subtypes of human ccRCC.

This paper has proposed an error searching method to search the solutions of errors that occurred in the unified commanding platform mix-deployed software (UCPMD). Because those errors belong to different stages or may be happened in different services, applications, IP ports, system software, or different versions of software, and those errors are also can be classified into different types. It is necessary to locate accurate reason that cause an error as well as find out its solution. The proposed error searching system applies Chinese keyword extraction and Chinese fuzzy matching between keywords, which considers the processed keywords as the index to find out the solutions of errors. Besides, the error searching system had made correspondence among errors, reasons, and solutions, and put them to different categories in terms of their characteristics, such that it is easy to manage, search, and use. Among others, we have added specialized thesaurus as the index of keywords, which enriches and completes the searching results. Because of the proposed error searching system evolves keyword extraction and keyword fuzzy matching technologies; it is more accurate to find out user-interested solutions.

When the space robot contacts with the target, due to the coupling between the manipulator and the base, the instantaneous impulse generated at the end may cause a large roll of the base. This paper proposes a new base attitude undisturbed planning algorithm. Firstly, the dynamic equation of the space robot based on the variable stiffness joint is established . Secondly, using Tent chaotic map, differential evolution strategy and nonlinear control parameter strategy to improve the grey wolf optimization algorithm, an improved gray wolf optimization algorithm based on Tent chaotic initialization and differential evolution strategy is constructed. The stiffness value of variable stiffness joint is used as the gray wolf individual, and the algorithm is applied to the base attitude undisturbed planning of the space robot. Finally, the simulation results show that the algorithm can achieve base attitude undisturbed planning very well.

With the increase in on-orbit maintenance and support requirements, the application of space manipulator is becoming more promising. However, how to control the vibration generated by the space manipulator has been a difficult problem to be solved. The advent of variable stiffness joint (VSJ) has brought about a dawn in solving this problem. But how to achieve coordinated control of joint angle and stiffness is still a problem to be solved, especially when considering system model parameter uncertainty, unknown disturbance and control input saturation. In order to realize the controllable attenuation of the vibration of the space flexible manipulator based on the variable stiffness joint, the dynamic model of the variable stiffness joint was constructed. Then the linear transformation and feedback linearization method are used to transform its complex nonlinear dynamic model system into a pseudo-linear system containing aggregate disturbance and input saturation constraints. This paper constructs a linear extended state observer (LESO) for estimating the state of unknown systems in pseudo-linear systems. Based on the idea of state feedback control, a Neural State Feedback Adaptive Robust (NSFAR) control is constructed by using Radial Basis Function Neural Network. The adaptive input saturation compensation control law is also designed by using Radial Basis Function Neural Network to deal with the input saturation compensation problem. The ultimate uniform bounded stability of the constructed system is proved by the stability analysis based on Lyapunov function. Finally, the effectiveness and superiority of the constructed tracking algorithm are verified by compared simulation and semi-physical experiment.

The covalently closed circular DNA (cccDNA), as the template of HBV transcription, plays a key role in the virus infection. The present study aimed to compare the effect of pegylated interferon (IFN)-α-2a with that of conventional IFN-α-2a on intrahepatic covalently closed circular (ccc)DNA in patients with chronic hepatitis B.Seventy-six HBeAg-positive chronic hepatitis B patients were randomly divided into two groups (n=38): group A was treated with interferon alpha-2a (IFN-α-2a) and group B was treated with peginterferon alpha-2a (peg IFN-α-2a). The intrahepatic level of cccDNA and its detection rate, levels of hepatitis B virus (HBV) DNA in liver and serum, histologic inflammation and some biochemistry parameters (alanine aminotransferase, aspartate aminotransferase and total bilirubin levels) were measured.The outcome of 48 weeks therapy showed that the mean level of intrahepatic HBV cccDNA level and its detection rate, the levels of HBV DNA and the histology and biochemistry parameters were significantly decreased following therapy in two groups (P0.05). While, the reductions in the group treated with peg IFN-α-2a were greater (P0.05).It may be concluded that the ability of the peg IFN-α-2a to clear and suppress cccDNA and HBV DNA was superior compared with that of conventional IFN-α-2a. Furthermore, the effects of peg IFN-α-2a on histology and biochemistry parameters were also more obvious than conventional IFN-α-2a.

It is significantly important to have the knowledge of electromagnet situation of battlefield, because it contains a lot of useful information to understand the situation of the whole battlefield. Electromagnet situation visualization would be very useful to help people to understand the situation, and handle battlefield situation, such as the size and quality of the electromagnetic radiation source, target objects, and operational purposes by the two parties engaged in combat scale. This paper proposes two electromagnet situation visualization methods, one is an isoline tracking algorithm based on floating rectangle and the other is an isoline filling algorithm based on linear interpolation, which also solves the problem of low accuracy and low efficiency. This paper also implements and displays the visualization results using different ways of demonstration modules, which show that the visualization results are more intuitive.

Nowadays a great amount of space debris threat the safety of space activities, so the space debris removal becomes a hot research field. In particular, on the base of space mechanical arm technology, using mechanical arm to remove space debris proves feasible in the implementation. Traditional space mechanical arms are rigid arms, and in consideration of the uncontrolled momentum of rigid arm, this paper intend to use flexible arm to capture space debris, which can achieve the purpose of stably controlling collision momentum. According to the whole task process that flexible arm captures space debris, this paper built a model of flexible arm and space debris, and establishes their mathematics models. The simulation system is constructed based on the models, and use I/O Completion Port (IOCP) model to ensure the real-time transportation of data produced in collision. Finally, this paper designs a simulation application case to verify the ability of simulation system to support space missions.

Aiming at the problem of harsh operating condition of the space manipulator and not being able to support great collision Momentum, this paper proposes a new concept and technical method, called soft-contact technology. According to this, the paper designs a space manipulator joint configuration based on bionics and carries out its rigid-flexible composite characteristic simulation. Simulation results show that the rigid member of the joint configuration has the ability to complete the path planning. meanwhile the flexible controllable damper is able to implement attenuate collision momentum between the base and the manipulator, and transfers stepped collision momentum to harmonic attenuation momentum.

In order to solve the problem of harsh operating condition of the space manipulator, and the problem of not being able to afford great collision Momentum, this paper proposes a new technical method, namely soft-contact technology. According to the proposed method, the dynamic model of space flexible manipulator is built up based on Kane's equations. Then this paper makes a comparison simulation between dynamic models designed by ADAMS using same dynamic parameters. Simulation show that the curves obtained by Kane's equations and ADAMS are basically the same, so the correctness of the dynamic model of the space flexible manipulator based on Kane's equation has been proved.

The base attitude of a free-floating space robot is disturbed during capturing targets. Based on the variable stiffness technology, this paper presents a compliance control strategy for minimizing the base attitude disturbance. Firstly, the dynamic model of space manipulator system is established by using the Lagrange equation. Secondly, the differential evolution algorithm is utilized to design the control strategy of variable stiffness joint space manipulator. The simulation results reflect that the influence introduced by impact is obviously reduced, which verify the effectiveness of the control strategy.

Information integrated decision system (IIDS) integrates multiple sub-system developed by many facilities, including almost hundred kinds of software, and provides with various services, such as email, short messages, drawing and sharing, etc., which also supports two types of network, WLAN and Wi-Fi. Because of the underlayer protocols are different, user standards are not unified, and many errors are happened during the stages of setup, configuration, and operation, which seriously affect the usage. Because the errors are various, which maybe happened in different operation phases, stages, TCP/IP communication protocol layers, and sub-system software. It is necessary to design a network online monitoring tool for IIDS. In order to solve the above problems, this paper studies on network online monitoring based on IIDS, which provides strong theory and technology supports for the operating and communicating of IIDS.

With the increase of on-orbit maintenance and support requirements, the application of a space manipulator is becoming more promising. In actual operation, the strong coupling of the free-floating space robot itself and the unknown disturbance of the contact target caused a major challenge to the robot base posture control. Traditional Reaction Null Space (RNS) motion planning and control methods require the construction of precise dynamic models, which is impossible in reality. In order to solve this problem, this paper proposes a new Adaptive Reaction Null Space (ARNS) path planning and control strategy for the contact of free-floating space robots with unknown targets. The ARNS path planning strategy is constructed by the Variable Forgetting Factor Recursive Least Squares (VFF&ndash, RLS) algorithm. At the same time, a robust adaptive control strategy based on the Strategy Self-Adaption Differential Evolution&ndash, Extreme Learning Machine (SSADE&ndash, ELM) algorithm is proposed to track the dynamic changes of the planned path. The algorithm enables us to intelligently learn and compensate for the unknown disturbance. Then, this paper constructs a robust controller to compensate model uncertainty. A striking feature of the proposed strategy is that it does not require an accurate system model or any information about unknown attributes. This design can dynamically implement RNS path tracking performance. Finally, through simulation and experiment, the proposed algorithm is compared with the existing methods to prove its effectiveness and superiority.

In view of the current fierce competition for electromagnetic power among countries, it is necessary to accelerate the simulation of frequency equipment in complex electromagnetic environments, and to construct complex electromagnetic environment simulation scenarios under joint combat conditions. How to construct the complex electromagnetic environment that meets up with the requirement of battlefields, and to improve combat command and training capabilities are the current research problems. Thus, this paper studies the simulation and calculation of the complex electromagnetic environment in the battlefield, and proposes and designs a system for the calculation and analysis of the complex electromagnetic environment of battlefield. The system can be used to estimate radio wave propagation of each frequency equipment, to analyse and compute complex electromagnetic situation of the battlefield, and visualize them. The above estimation, analysis, and computation are obtained according to the displacement of frequency equipment, and battlefield environment, such as geography information and meteorological information. The proposed system can obtain the impact of electromagnetic environment of the battlefield on various types of frequency equipment, and provide battlefield electromagnetic information protection for equipment application.

More than just an empty shell: Multishelled Co3O4 microspheres were synthesized as anode materials for lithium-ion batteries in high yield and purity. As their porous hollow multishell structure guarantees a shorter Li+ diffusion length and sufficient void space to buffer the volume expansion, their rate capacity, cycling performance, and specific capacity were excellent (1615.8 mA?h?g-1 in the 30th cycle for triple-shelled Co3O4; see graph).

Aiming at the problem that the operation condition of space manipulator is very tough, which cannot afford large collision momentum. This paper proposes a new concept, called soft-contact technology. According to this technology, this paper designs a space manipulator joint configuration based on integrated double joints, and carries out simulation analysis on its rigid-flexible compound characteristic. Simulation results show that the rigid component of the joint configuration has the ability of path planning. Meanwhile, the flexible controllable damper is able to implement the attenuate collision momentum between the base and the manipulator, and the transfer from stepped collision momentum to harmonic attenuation momentum.

This monograph focuses on developing methods for constructing learning paths in terms of “learning resources,” “learning approaches,” and “learning quality” to support student learning. To find out a model that helps teachers to design teaching approaches, we define different teaching approaches for learning activities and organize them into a learning path, which indicates the learning sequence of different learning activities. And to find out the appropriate learning resources, we automatically generate well-structured learning resources from loosely connected Web resources.

The general research methodology we have applied includes both qualitative method and quantitative method, which is used to verify if teachers and students are satisfied with our research work as well as to verify if our research work can provide with better teaching approaches.

In the last chapter, we mainly formulate learning activities to construct the learning path based on learning outcomes in terms of how to learn. We still need to design learning resources forming the learning contents that are used in a learning path to define what to learn.

I would like to introduce some terminologies, which are all very important concepts of this monograph.

To answer the first research question of how to learn, which requires finding out the teaching approaches and the sequence of learning, we have proposed a fine-grained outcome-based learning path (LP) model. In order to verify this method, we have implemented a prototype of this model. Next, we conduct a user study, in which we have invited teachers to try out our prototype and evaluate it as well as give us feedbacks in terms of their user experiences. This user study is mainly carried out through 3 parts including an introduction on the system, user interaction with the prototype, and evaluation questionnaires.