Cooperative Anti-Jamming and Interference Mitigation for UAV Networks: A Local Altruistic Game Approach

To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.

Current-Aided Multiple-AUV Cooperative Localization and Target Tracking in Anchor-Free Environments

In anchor-free environments,where no devices with known positions are available,the error growth of autonomous underwater vehicle(AUV)localization and target tracking is unbounded due to the lack of references and the accumulated errors in inertial measurements.This paper aims to improve the localization and tracking accuracy by involving current information as extra references.We first integrate current measurements and maps with belief propagation and design a distributed current-aided message-passing scheme that theoretically solves the localization and tracking problems.Based on this scheme,we propose particle-based cooperative localization and target tracking algorithms,named CaCL and CaTT,respectively.In AUV localization,CaCL uses the current measurements to correct the predicted and transmitted position information and alleviates the impact of the accumulated errors in inertial measurements.With target tracking,the current maps are applied in CaTT to modify the position prediction of the target which is calculated through historical estimates.The effectiveness and robustness of the proposed methods are validated through various simulations by comparisons with alternative methods under different trajectories and current conditions.

Improved GNSS Cooperation Positioning Algorithm for Indoor Localization

For situations such as indoor and underground parking lots in which satellite signals are obstructed,GNSS cooperative positioning can be used to achieve highprecision positioning with the assistance of cooperative nodes.Here we study the cooperative positioning of two static nodes,node 1 is placed on the roof of the building and the satellite observation is ideal,node 2 is placed on the indoor windowsill where the occlusion situation is more serious,we mainly study how to locate node 2 with the assistance of node 1.Firstly,the two cooperative nodes are located with pseudo-range single point positioning,and the positioning performance of cooperative node is analyzed,therefore the information of pseudo-range and position of node 1 is obtained.Secondly,the distance between cooperative nodes is obtained by using the baseline method with double-difference carrier phase.Finally,the cooperative location algorithms are studied.The Extended Kalman Filtering(EKF),Unscented Kalman Filtering(UKF)and Particle Filtering(PF)are used to fuse the pseudo-range,ranging information and location information respectively.Due to the mutual influences among the cooperative nodes in cooperative positioning,the EKF,UKF and PF algorithms are improved by resetting the error covariance matrix of the cooperative nodes at each update time.Experimental results show that after being improved,the influence between the cooperative nodes becomes smaller,and the positioning performance of the nodes is better than before.

Healthcare Levels Cooperation, Action in Local Health System to Better Coordinate the Delivery of Healthcare

The healthcare system＇s approach considers the complexity and interactions between organized elements. In continuous processing, healthcare systems are affected by their constituent elements, themselves modified with each system change. To secure and optimize the system of care, collaboration between levels is necessary. Almost no documented experience to better coordination of levels of care in the Belgian system is available. To improve the quality of care, the system needs collaborative coordination between stakeholders. Good coordination improves the quality of patient care, it makes quality more efficient and optimal care. This coordination between care lines must be collaborative. Interactional communication is the founding element of inter-professional collaboration. A good self-esteem improves the relationship between actors in the health system and supports the initiatives and adaptability. It contributes therefore to an increase of the quality of care. The interactional Local Health System promotes cooperation in the relevant health network. Consultation and coordination between the actors involved and motivated bring care quality and operational solutions. This dynamic modality of exchanges appears fruitful as participants continue to meet and coordinate care, even after the official end of the action-research. The climate became conducive to solving real problems through the skills developed in the LHS.

China-Africa Local Government Cooperation Essential for Growth

The First Forum on China-Africa Local Government Cooperation was held in Beijing on August 27-28, 2012. Vice President of the Chinese People＇s Association for Friendship with Foreign Countries （CPAFFC） Feng Zuoku, shared his insights on the Forum and China-Africa local-level cooperation with ChinAfrica reporter Yu Nan. Excerpts follow：

Cooperative navigation and localization for multiple UUVs

The authors proposed a moving long baseline algorithm based on the extended Kalman filter （EKF） for cooperative navigation and localization of multi-unmanned underwater vehicles （UUVs）. Research on cooperative navigation and localization for multi-UUVs is important to solve navigation problems that restrict long and deep excursions. The authors investigated improvements in navigation accuracy. In the moving long base line （MLBL） structure, the master UUV is equipped with a high precision navigation system as a node of the moving long baseline, and the slave UUV is equipped with a low precision navigation system. They are both equipped with acoustic devices to measure relative location. Using traditional triangulation methods to calculate the position of the slave UUV may cause a faulty solution. An EKF was designed to solve this, combining the proprioceptive and exteroceptive sensors. Research results proved that the navigational accuracy is improved significantly with the MLBL method based on EKF.

Cooperative localization against GPS signal loss in multiple UAVs flight

Based on multiple unmanned aerial vehicles（UAVs） flight at a constant altitude,a fault-tolerant cooperative localization algorithm against global positioning system（GPS） signal loss due to GPS receiver malfunction is proposed.Contrast to the traditional means with single UAV,the proposed method is based on the use of inter-UAV relative range measurements against GPS signal loss and more suitable for the small-size and low-cost UAV applications.Firstly,for re-localizing an UAV with a malfunction in its GPS receiver,an algorithm which makes use of any other three healthy UAVs in the cooperative flight as the reference points for re-localization is proposed.Secondly,by using the relative ranges from the faulty UAV to the other three UAVs,its horizontal location can be determined after the GPS signal is lost.In order to improve an accuracy of the localization,a Kalman filter is further exploited to provide the estimated location of the UAV with the GPS signal loss.The Kalman filter calculates the variance of observations in terms of horizontal dilution of positioning（HDOP） automatically.Then,during each discrete computing time step,the best reference points are selected adaptively by minimizing the HDOP.Finally,two simulation examples in Matlab/Simulink environment with five UAVs in cooperative flight are shown to evaluate the effectiveness of the proposed method.

A Distributed Cooperative Localization Algorithm for Mobile Multi-platforms Oriented to Unpredicted Communication Topology

The cooperative localization(CL)is affected by the communication topology among the platforms.Based on the unscented Kalman filtering,the distributed CL(DCL)oriented to the unpredicted communication topology is investigated.To improve the adaptability,the character of the look-up Cholesky decomposition is exploited for the covariance matrix decomposing.Then,the distributed U transformation can be dynamically implemented according to the available communication topology.In the proposed algorithm,the global information is not required for the individual,and only the available information from the neighbor is used.Each platform’s state can be estimated independently.The error covariance of the state estimates can be updated in the single platform.The algorithm is adaptive to any serial communication topologies where the measuring to the measured platform is a starting path.The applicability of the proposed algorithm to unpredicted communication topology is improved,remaining equivalent localization performance to free connection communication.

An Area Optimization Based Cooperative Localization Algorithm with Node Selection

In recent years,position information has become a key feature to drive location and context aware services in mobile communication.Researchers from all over the world have proposed many solu-tions for indoor positioning over the past several years.However,due to weak signals,multipath or non-line-of-sight signal propagation,accurately and efficiently localizing targets in harsh indoor environments re-mains a challenging problem.To improve the perfor-mance in harsh environment with insufficient anchors,cooperative localization has emerged.In this paper,a novel cooperative localization algorithm,named area optimization and node selection based sum-product al-gorithm over a wireless network(AN-SPAWN),is de-scribed and analyzed.To alleviate the high compu-tational complexity and build optimized cooperative cluster,a node selection method is designed for the cooperative localization algorithm.Numerical experi-ment results indicate that our proposed algorithm has a higher accuracy and is less impacted by NLOS errors than other conventional cooperative localization algo-rithms in the harsh indoor environments.

Distributed cooperative localization for sparse communication network with multi-locating messages

In cooperative localization with sparse communication networks, an agent maybe only receives part of locating messages from the others. It is difficult for the receiver to utilize the part instead of global knowledge. Under the extended Kalman filtering, the utilization of the locating message is maximized by two aspects： the locating message generating and multi-locating messages fusing. For the former, the covariance upper-bound technique, by introducing amplification coefficients, is employed to remove the dependency of locating messages on the global knowledge. For the latter, an optimization model is setup; the covariance matrix determinant of the receiver＇s state estimate, expressed as a function of the amplification coefficients, is selected as the optimization criterion, under linear constraints on the amplification coefficient characteristics and the communication connectivity. Using the optimization solution, the local optimal state of the receiver agent is obtained by the weighting fusion. Simulation with seven agents is shown to evaluate the effectiveness of the proposed algorithm.

Women＇s Cooperatives Contributions to Local Region Economy： Seferihisar Agricultural Cooperative Development Model-Turkey

The cooperative movement has played a very important role in the social and economic development of all countries since 19th eentury＇s second half. Cooperatives provide health, housing, and banking services; they promote education and gender equality; they protect the environment and workers＇ rights. According to 2014＇s data, the total number of cooperatives is 79,486 in Turkey, while the total number of partners of cooperatives is approximately 7.8 million. The research＇s sample group ＂Hidirlik Agricultural Development Cooperative＂ was founded by the wife of the Seferihisar＇s mayor and six women. It has been a subject of curiousity that the contributions of the cooperative have developed the economy of the region since 2010. Therefore, various questions asked to the president and members of the cooperative, and significant results were obtained. In this research ＂Interview technique＂ was used. The fact that within the boundaries of local governments, the establishment of ＂women＇s cooperatives＂ and their active management can be supported with 10 basic criteria for the regional and national development can be predicted. These dimensions： ecological balance and sensitivity, the revival of the tourism sector, the mobility of logistics activities, new investments and increase of land value, the increase of women employment, the increase of healthy living standards, increase of competitiveness and trade earnings, the creation of new brands, widespread of the agricultural sector, and the increase of social and educational level of women. The similiar implementation of ＂Seferihisar Women＇s Cooperatives Model＂ in the research is considered form an important enterprenurship model not only in Turkey but also for all countries.

On Localization of ELT at Sino-foreign Cooperative Institutions

With the rapid development of educational reform and innovation,Sino-foreign Cooperative Institutions have made greatachievements.Especially after China entered the WTO,as foreign universities educational resources are introduced,the localiza-tion of English language teaching arouse much attention.This paper is to explore and study the Localization of English LanguageTeaching at Sino-foreign Cooperative Institutions.And then is the study on localization of English language teaching at SIAS Inter-national University.Through the evidence of this paper shows,it can pose a theory reference and support to Sino-foreign Coopera-tive Institutions.

Compensation Algorithm Based on Estimation State for Transmission Delay in Cooperative Localization

In order to maximize the utilization of the observation information in the cooperative localization,a compensation algorithm based on the estimation state is presented for transmission delay.Under the framework of the Kalman filter,two different processes of state estimating with and without transmission delay are investigated and contrasted.The expression of difference quantity caused by transmission delay is derived.It is used to compensate the present estimation state instead of the observed information compensation.According to the characteristics of state transition matrix,an equivalent expression of which successively impacts on the covariance factor in delay time is obtained.The simulation results show that the present estimated state is effectively corrected by transmission information and the relevance among agents is accurately updated.As a result,a higher positioning accuracy is achieved.Meanwhile,the consumption of recording and multiplication of the state transition matrix is saved.

Cooperative Nodes Localization for Three-Dimensional Underwater Wireless Sensor Network Based on Weighted Centroid Localization Algorithm

The underwater wireless sensor network(UWSN) has the features of mobility by drifting,less beacon nodes,longer time for localization and more energy consumption than the terrestrial sensor networks,which makes it more difficult to locate the nodes in marine environment.Aiming at the characteristics of UWSN,a kind of cooperative range-free localization method based on weighted centroid localization(WCL) algorithm for three-dimensional UWSN is proposed.The algorithm assigns the cooperative weights for the beacon nodes according to the received acoustic signal strength,and uses the located unknown nodes as the new beacon nodes to locate the other unknown nodes,so a fast localization can be achieved for the whole sensor networks.Simulation results indicate this method has higher localization accuracy than the centroid localization algorithm,and it needs less beacon nodes and achieves higher rate of effective localization.

Networking-GPS: Cooperative Vehicle Localization Using Commodity GPS in Urban Area

A challenging issue in intelligent transportation systems （ITS） is to accurately locate moving vehicles in urban area. Considerable ef- forts have been made to improve the localization accuracy of standalone GPS receivers. However, through empirical study, we found that the latitude and longitude values generated by GPS receivers fluctuate significantly because of the muhipath effect in urban ar- eas. The relative distances between neighboring vehicles with similar GPS signal data in terms of satellite sets and signal strength are much more stable in such a scenario. In this paper, we propose a cooperative localization algorithm, Networking-GPS, to improve the accuracy of location information for vehicular networks in urban area using commodity GPS receivers. First, atom redundantly rigid graphs of vehicles are constructed according to the similarity of neighboring GPS data. Then, through rigidity expansion, local accura- cy can enforce global accuracy. Extensive simulations based on the real road network and trace data of vehicle mobility demonstrate that Networking-GPS can improve the accuracy of the entire system.

A Multi-Vehicle Cooperative Localization Method Based on Belief Propagation in Satellite Denied Environment

The global navigation satellite system(GNSS)is currently being used extensively in the navigation system of vehicles.However,the GNSS signal will be faded or blocked in complex road environments,which will lead to a decrease in positioning accuracy.Owing to the higher-precision synchronization provided in the sixth generation(6G)network,the errors of ranging-based positioning technologies can be effectively reduced.At the same time,the use of terahertz in 6G allows excellent resolution of range and angle,which offers unique opportunities for multi-vehicle cooperative localization in a GNSS denied environment.This paper introduces a multi-vehicle cooperative localization method.In the proposed method,the location estimations of vehicles are derived by utilizing inertial measurement and then corrected by exchanging the beliefs with adjacent vehicles and roadside units.The multi-vehicle cooperative localization problem is represented using a factor graph.An iterative algorithm based on belief propagation is applied to perform the inference over the factor graph.The results demonstrate that our proposed method can offer a considerable capability enhancement on localization accuracy.

Operating in Tandem Chinese experts in Sao Tome and Principe cooperate with local farmers to raise medical standards in the breeding industry

Santomean pig farmer Simao Vicente was hopeful when he came to ask Zou Rui for help. His pig was suffering from hernia, and Zou, a 42-year-old Chinese agricultural expert working in Sao Tomé and Príncipe, was the only person on the island who could provide emergency surgery.

美国社区学院产学研合作教育的经验与启示

美国产学研合作教育起步较早,积累了丰富的办学实践经验,具有完善的法律保障体系和灵活多样的合作方式,形成了独特的办学模式。尤其是社区学院的校企合作教育,有效促进了美国地方社会经济的发展。美国社区学院的校企产学研合作教育经历了形成、发展、成熟和繁荣四个时期,在服务地方社会经济和人才培养方面取得了显著成效,积累了丰富的成功经验:一是建立健全法律制度,为开展产学研合作教育提供保障;二是建立政府、社区学院和企业多元协作体系,推动校企产学研合作良性运转;三是依托项目群推动社区学院与企业开展深度合作,搭建校企产学研合作教育的桥梁;四是形成社区学院与企业联合培养人才模式,搭建校企产学研合作教育的纽带;五是满足地方社会经济发展的需求,抓住校企产学研合作教育的生命线。我国地方高校应借鉴美国社区学院发展的经验,充分发挥地方高校与企业之间的优势资源,健全校企产学研合作教育的法律体系,建立产学研合作教育一体化发展模式与管理机制,依托项目推动地方高校校企产学研合作教育,推动地方社会经济发展。

“在地国际化”视域下高等职业教育中外合作办学质量认证体系研究

“在地国际化”是突破高校师生跨境流动的传统观念,在本土创设国际化学习环境、教学资源和育人机制的教育模式。中外合作办学是高等职业教育“在地国际化”的载体与表现形式。在“在地国际化”视域下,中外合作办学存在理念更迭滞缓、认证系统与评价体系未协同、缺乏国际通行认证指标体系等问题,高等职业教育中外合作办学质量认证体系的建构将满足面向全球,培养国际化人才质量保障需求。依据“输入-环境-输出”理论模型,高等职业教育中外合作办学“在地”发展质量认证体系的构建与应用旨在凸显夯实高等职业教育国际化人才培养质量观、实现国际化高技能人才在地培养的实质等效和增强“在地”培养国际化技术技能型人才实力的应用价值。