Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view

In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets.

Policy Iteration for Optimal Control of Discrete-Time Time-Varying Nonlinear Systems

Aimed at infinite horizon optimal control problems of discrete time-varying nonlinear systems,in this paper,a new iterative adaptive dynamic programming algorithm,which is the discrete-time time-varying policy iteration(DTTV)algorithm,is developed.The iterative control law is designed to update the iterative value function which approximates the index function of optimal performance.The admissibility of the iterative control law is analyzed.The results show that the iterative value function is non-increasingly convergent to the Bellman-equation optimal solution.To implement the algorithm,neural networks are employed and a new implementation structure is established,which avoids solving the generalized Bellman equation in each iteration.Finally,the optimal control laws for torsional pendulum and inverted pendulum systems are obtained by using the DTTV policy iteration algorithm,where the mass and pendulum bar length are permitted to be time-varying parameters.The effectiveness of the developed method is illustrated by numerical results and comparisons.

Research on the effects of command-and-control and market-oriented policy tools on China's energy conservation and emissions reduction innovation

The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in academia about the establishment of "weak" and "narrow" versions of PH. Based on the panel data of application for patent of energy conservation and emission reduction(ECER) technology of Chinese city scale during 2008-2014, comprehensive energy price, pollutant emission, etc., mixed regression model and systematic generalized method of moments method were adopted, respectively,to study the impact of market-oriented and command-and-control policy tool on China's ECER technology innovation. The results show that the environmental regulation hindered the technological innovation in the immediate phase; however, it turned out to be positive in the first-lag phase. Hence, the establishment of "weak" PH is time-bounded. The command-and-control policy tool played a more positive role in promoting technological innovation in the first-lag phase than market-oriented policy tool. Therefore, "narrow" PH is not tenable. The reason is that the main participants of China's ECER technology innovation are state-owned companies and public institutions. Regionally speaking, the impact which command-and-control policy tool has on technological innovation at sight was nonsignificant in the eastern, the central, and the western regions of China whilst market-oriented policy tool had a negative effect. And market-oriented policy tool in the central region had strongest negative effect, which would diminish in the eastern region and become weakest in the western region. This was related to regional energy consumption level and the market economic vitality.

基于Command and Control通信信道流量属性聚类的僵尸网络检测方法

僵尸网络(Botnet)是一种从传统恶意代码形态进化而来的新型攻击方式,为攻击者提供了隐匿、灵活且高效的一对多命令与控制信道(Command and Control channel,C&C)机制,可以控制大量僵尸主机实现信息窃取、分布式拒绝服务攻击和垃圾邮件发送等攻击目的。该文提出一种与僵尸网络结构和C&C协议无关,不需要分析数据包的特征负载的僵尸网络检测方法。该方法首先使用预过滤规则对捕获的流量进行过滤,去掉与僵尸网络无关的流量;其次对过滤后的流量属性进行统计;接着使用基于X-means聚类的两步聚类算法对C&C信道的流量属性进行分析与聚类,从而达到对僵尸网络检测的目的。实验证明,该方法高效准确地把僵尸网络流量与其他正常网络流量区分,达到从实际网络中检测僵尸网络的要求,并且具有较低的误判率。

基于主动网络的Policy-control研究

结合主动网络的机制和IntServ体系结构，提出了一种主动网络支持的基于代理-管理者的策略控制机制，可以简化中间节点策略控制复杂性，保证在一个管理域中的策略一致性，并且可以实现控制策略代理的动态部署、更新。在此基础上，提出了基于发送用户的策略控制方法。

Adaptive optimization of agile organization of command and control resource

Adaptive optimization is one of the means that agile organization of command and control resource （AOC2R） adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put forward by analyzing the interrelating concept and research. The model takes the adaptive process as a multi-stage decision making problem. The 2-phases method is presented to calculate the model, which obtains the related parameters by running the colored Petri net （CPN） model of AOC2R and then searches for the result by ant colony optimization （ACO） algorithm integrated with genetic optimization techniques. The simulation results demonstrate that the proposed algorithm greatly improves the performance of AOC2R.

Command Filtered Finite/Fixed-time Heading Tracking Control of Surface Vehicles

This paper investigates the heading tracking problem of surface vehicles with unknown model parameters.Based on finite/fixed-time control theories and in the context of command filtered control,two novel adaptive control laws are developed by which the vehicle can track the desired heading within settling time with all signals of the closed-loop system are uniformly bounded.The effectiveness and performance of the schemes are demonstrated by simulations and comparison studies.

"Hollow Village" Evolution and Policy Control from the Perspective of Rural Urbanization: A Case Study of Jiangsu Province

From the perspective of the process of urbanization,this paper puts forward the corresponding public policy control by analyzing the characteristics of " hollowing" at different stages of urbanization. Moreover,the paper focuses on the stage of China's current urbanization.Based on the survey of migrant workers,this paper evaluates China's current policies,and argues that the rural " hollowing" is an objective that accompanies urbanization. At different stages of the process of urbanization,the rural " hollowing" presents different characteristics. Local governments should make policy and plan based on the different stages of local urbanization and local conditions,because of the extent of regional differences in economic and social development. This paper aims to guide the rural " hollowing" to develop toward the right direction.

Survey of <i>C. difficile</i>-Specific Infection Control Policies in Local Long-Term Care Facilities

Introduction: The incidence and severity of Clostridium difficile infection (CDI) has been increasing and long-term care facility (LTCF) residents are at high risk given their age, co-morbidities, and high antibiotic exposure. Infection control policies are crucial for controlling CDI, but there are currently no regulatory guidelines in the United States. Therefore, we evaluated infection control policies in local LTCFs to define the CDI-specific policies and the administrative and staff understanding of CDI, so as to identify perceived barriers for compliance. Methods: IRB approval was sought and exemption granted, all 8 local LTCFs were asked to participate. Each facility was visited by study personnel who interviewed the administrative Infection Control Practitioner (ICP) and 3-4 Licensed Practical Nurses (LPNs) with distinct survey format. Infection control policies were then compared to the SHEA recommendations for CDI in LTCFs. Results: Of the eligible facilities, 75% (n = 6) participated. ICP (n = 6) and LPNs (n = 21) were interviewed. All facilities accept residents with active CDI and 2 had written CDI-specific infection control policies. All facilities had hand hygiene or glove use policies and 2 had policies for the use of sporicidal environmental cleaning. No facility restricted antibiotic use. Each facility has a policy to instruct their staff through in-services, either annually or upon new hire, but 33% (n = 7) LPNs reported no facility-based CDI training. While 80% (n = 17) of LPNs felt comfortable with the facility CDI policies, only 11 accurately restated it. ICPs felt the most relevant barrier to staff compliance was time constraints (n = 4, 67%), however, LPNs felt it was limited knowledge (n = 10, 48%) and poor communication (n = 2, 10%). Discussion and Conclusions: With the increasing incidence and severity of CDI in LCTF, few of the facilities surveyed had CDI-specific policies. Despite CDI-specific training, there is a perceived knowledge and communication gap for staff caring for residents with CDI.

STUDY ON THE OPTIMIZATION OF TRANSPORT CONTROL POLICY IN COMMUNICATION NETWORK

In communication networks with policy-based Transport Control on-Demand (TCoD) function,the transport control policies play a great impact on the network effectiveness. To evaluate and optimize the transport policies in communication network,a policy-based TCoD network model is given and a comprehensive evaluation index system of the network effectiveness is put forward from both network application and handling mechanism perspectives. A TCoD network prototype system based on Asynchronous Transfer Mode/Multi-Protocol Label Switching (ATM/MPLS) is introduced and some experiments are performed on it. The prototype system is evaluated and analyzed with the comprehensive evaluation index system. The results show that the index system can be used to judge whether the communication network can meet the application requirements or not,and can provide references for the optimization of the transport policies so as to improve the communication network effectiveness.

Command and Control Cities in Global Space-economy Before and after 2008 Geo-economic Transition

The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations.Existing studies have yet to depict the detrimental impacts on city's command and control functions induced by the sub-prime mortgage crisis together with its residual wave of global economic recession on the global spatial economy.Recent and previous studies have produced an 'instant history' of the global spatial economy before the global economic downturn undermines the global economy in late 2008.However,the waxes and wanes of major cities' command and control functions on the global economic arena before and after the outbreak of financial crisis and its associated geo-economic transitions are still poorly understood.This paper attempts to contribute a new set of customized data to update and fill in the gap in the literature with the investigation of the command and control functions of cities around the world from 2005 to 2009.Particular attentions are paid to the time-space relationship of the geo-economic transition that can capture the recent historical images of the command and control situation of different cities in the world.

A policy and technical measures for controlling soil and water loss in the Loess Plateau of China

Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for erosion in this area, and puts forward a comprehensive controlling policy on the basis of the principles of ecology and practise of Chinese scientists for 40 years. In conformity with the policy, a number of technical measures for controlling soil and water loss are suggested.

Detecting conflict of heterogeneous access control policies

Policy conflicts may cause substantial economic losses.Although a large amount of effort has been spent on detecting intra-domain policy conflict,it can not detect conflicts of heterogeneous policies.In this paper,considering background knowledge,we propose a conflict detection mechanism to search and locate conflicts of heterogeneous policies.First,we propose a general access control model to describe authorization mechanisms of cloud service and a translation scheme designed to translate a cloud service policy to an Extensible Access Control Markup Language(XACML)policy.Then the scheme based on Multi-terminal Multi-data-type Interval Decision Diagram(MTMIDD)and Extended MTMIDD(X-MTMIDD)is designed to represent XACML policy and search the conflict among heterogeneous policies.To reduce the rate of false positives,the description logic is used to represent XACML policy and eliminate false conflicts.Experimental results show the efficiency of our scheme.

Effects of policies and containment measures on control of COVID- 19 epidemic in Chongqing

BACKGROUND Coronavirus disease 2019(COVID-19)is an emerging,rapidly evolving disease that spreads through the respiratory system and is highly contagious.In March 2020,the World Health Organization declared the COVID-19 outbreak a pandemic.In China,the pandemic was controlled after 2 mo through effective policies and containment measures.Describing the detailed policies and containment measures used to control the epidemic in Chongqing will provide a reference for the prevention and control of COVID-19 in other areas of the world.AIM To explore the effects of different policies and containment measures on the control of the COVID-19 epidemic in Chongqing.METHODS Epidemiological data on COVID-19 in Chongqing were prospectively collected from January 21 to March 15,2020.The policies and prevention measures implemented by the government during the epidemic period were also collected.Trend analysis was performed to explore the impact of the main policy measures on the effectiveness of the control of COVID-19 in Chongqing.As of March 15,the cumulative incidence of COVID-19 in Chongqing was 1.84/100000(576 cases)and the infection fatality rate was 1.04%(6/576).The spread of COVID-19 was controlled by effective policies that involved establishing a group for directing the COVID-19 epidemic control effort;strengthening guidance and supervision;ensuring the supply of daily necessities and medical supplies and equipment to residents;setting up designated hospitals;implementing legal measures;and enhancing health education.Medical techniques were implemented to improve the recovery rate and control the epidemic.Policies such as“the lockdown of Wuhan”,“initiating a first-level response to major public health emergencies”,and“implementing the closed management of residential communities”significantly curbed the spread of COVID-19.Optimizing the diagnosis process,shortening the diagnosis time,and constructing teams of clinical experts facilitated the provision of“one team of medical experts for each patient”treatment for severe patients,which significantly improved the recovery rate and reduced the infection fatality rate.CONCLUSION The prevention policies and containment measures implemented by the government and medical institutions are highly effective in controlling the spread of the epidemic and increasing the recovery rate of COVID-19 patients.

Research on the Policies and Means Changes of Macro Regulation and Control of Chinese and Foreign Governments

In the process of economic development, government uses the "visible hand" to achieve macroeconomic regulation and control for "market failure", which has been common knowledge among people after World War II. Comparing policy and means adopted by Chinese and foreign governments in macro regulation and control, we can see that the choice is different in different historical periods and the change of emphasis in macro regulation and control policy and means has the convergence tendency. We can make the following conclusion from research of the change rules of macro regulation and control means in the market economic condition of Chinese and foreign governments: supply-side structural reform in China complies with the basic rules of development of market economy.

Key technologies and applications of intelligent dispatching command for high-speed railway in China

Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new HSR dispatching command system that integrates the widely used CTC in China with the practical service requirements of intelligent dispatching.This paper aims to propose key technologies and applications for intelligent dispatching command in HSR in China.Design/methodology/approach–This paper first briefly introduces the functions and configuration of the intelligent CTC system.Some new servers,terminals and interfaces are introduced,which are plan adjustment server/terminal,interface for automatic train operation(ATO),interface for Dynamic Monitoring System of Train Control Equipment(DMS),interface for Power Supervisory Control and Data Acquisition(PSCADA),interface for Disaster Monitoring,etc.Findings–The key technologies applied in the intelligent CTC system include automatic adjustment of train operation plans,safety control of train routes and commands,traffic information data platform,integrated simulation of traffic dispatching and ATO function.These technologies have been applied in the Beijing-Zhangjiakou HSR,which commenced operations at the end of 2019.Implementing these key intelligent functions has improved the train dispatching command capacity,ensured the safe operation of intelligent HSR,reduced the labor intensity of dispatching operators and enhanced the intelligence level of China’s dispatching system.Originality/value–This paper provides further challenges and research directions for the intelligent dispatching command of HSR.To achieve the objectives,new measures need to be conducted,including the development of advanced technologies for intelligent dispatching command,coping with new requirements with the development of China’s railway signaling system,the integration of traffic dispatching and train control and the application of AI and data-driven modeling and methods.

THE OPTIMAL DEDUCTIBLE AND COVERAGE IN INSURANCE CONTRACTS AND EQUILIBRIUM RISK SHARING POLICIES

In this paper, we consider the optimal risk sharing problem between two parties in the insurance business: the insurer and the insured. The risk is allocated between the insurer and the insured by setting a deductible and coverage in the insurance contract. We obtain the optimal deductible and coverage by considering the expected product of the two parties' utilities of terminal wealth according to stochastic optimal control theory. An equilibrium policy is also derived for when there are both a deductible and coverage;this is done by modelling the problem as a stochastic game in a continuous-time framework. A numerical example is provided to illustrate the results of the paper.

Research on Multicloud Access Control Policy Integration Framework

Multicloud access control is important for resource sharing and security interoperability across different clouds,and heterogeneity of access control policy is an important challenge for cloud mashups.XACML is widely used in distributed environment as a declaratively fine-grained,attribute-based access control policy language,but the policy integration of XACML lacks formal description and theory foundation.Multicloud Access Control Policy Integration Framework(MACPIF)is proposed in the paper,which consists of Attribute-based Policy Evaluation Model(ABPEM),Four-value Logic with Completeness(FLC)and Four-value Logic based Policy Integration Operators(FLPIOs).ABPEM evaluates access control policy and extends XACML decision to four-value.According to policy decision set and policy integration characteristics,we construct FLC and define FLPIOs including Intersection,Union,Difference,Implication and Equivalence.We prove that MACPIF can achieve policy monotonicity,functional completeness,canonical suitability and canonical completeness.Analysis results show that this framework can meet the requirements of policy integration in Multicloud.

An Improved Pairing-Free Ciphertext Policy Framework for IoT

Internet of Things(IoT)enables devices to get connected to the internet.Once they are connected,they behave as smart devices thereby releasing sensitive data periodically.There is a necessity to preserve the confidentiality and integrity of this data during transmission in public communication channels and also permitting only legitimate users to access their data A key challenge of smart networks is to establish a secure end-to-end data communication architecture by addressing the security vulnerabilities of data users and smart devices.The objective of this research work is to create a framework encompassing Ciphertext policy Attribute-based Encryption scheme using block encryption and BLAKE hashing technique.An improved Pairing-Free-Ciphertext policy Attribute-based encryption algorithm has been developed to overcome the aforementioned challenges.Further,a comparative study has been performed between the proposed scheme and the different encryption algorithms.It is found that the proposed scheme scores well over the already existing schemes.The scheme is evaluated in terms of execution time and communication overhead.The robustness of the proposed scheme is also analyzed from the perspective of several security goals.

Knowledge and awareness of infection control practices among nursing professionals:A cross-sectional survey from South Asia and the Middle East

BACKGROUND The proficiency of nursing professionals in the infection prevention and control(IPC)practices is a core component of the strategy to mitigate the challenge of healthcare associated infections.AIM To test knowledge of nurses working in intensive care units(ICU)in South Asia and Middle East countries on IPC practices.METHODS An online self-assessment questionnaire based on various aspects of IPC practices was conducted among nurses over three weeks.RESULTS A total of 1333 nurses from 13 countries completed the survey.The average score was 72.8%and 36%of nurses were proficient(mean score>80%).43%and 68.3%of respondents were from government and teaching hospitals,respectively.79.2%of respondents worked in<25 bedded ICUs and 46.5%in closed ICUs.Statistically,a significant association was found between the knowledge and expertise of nurses,the country’s per-capita income,type of hospitals,accreditation and teaching status of hospitals and type of ICUs.Working in high-and upper-middleincome countries(β=4.89,95%CI:3.55 to 6.22)was positively associated,and the teaching status of the hospital(β=-4.58,95%CI:-6.81 to-2.36)was negatively associated with the knowledge score among respondents.CONCLUSION There is considerable variation in knowledge among nurses working in ICU.Factors like income status of countries,public vs private and teaching status of hospitals and experience are independently associated with nurses’knowledge of IPC practices.