On String Stable Control of Platoon of Automated Vehicles with Predecessor-successor Information Framework

For the constant distance spacing policy,the existing researches of the string stability focus on the single-predecessor information framework（SPIF） and predecessor-successor information framework（PSIF）.The research results demonstrated that the string stability could not be guaranteed with the SPIF,and then the PSIF was proposed to resolve this string instability.But the issue,whether the string stability can be guaranteed when applying the PSIF,is still controversial.Meanwhile,most of the previous researches on the string stability were conducted without consideration of the parasitic time delays and lags.In this paper,the practical longitudinal vehicle dynamics model is built with consideration of the parasitic time delays and lags existing in the actuators,sensors or the communication systems.Secondly,the detailed theoretical analysis of string stability in frequency domain is conducted to demonstrate that the classical linear control laws can not ensure the string stability when applying both the symmetrical PSIF（SPSIF） and asymmetrical PSIF（APSIF）.Thirdly,a control law,which adds the position and velocity information of the leading vehicle,is proposed to guarantee string stability for small/medium platoon,and the other control law,which adds the acceleration information of the controlled vehicle,is proposed to guarantee string stability for large platoon as well as small/medium platoon.Finally,the comparative simulation is conducted to confirm the conducted analysis and the proposed control laws.The conducted research completes the means to analyze the string stability in frequency domain,provides the parameters＇ reference for the design and implementation of the practical automatic following controllers,and improves the reliability and stability of the platoon of automatic vehicles.

Access Request Trustworthiness in Weighted Access Control Framework

Weighted factor is given to access eontrol policies to express the importanceof policy and its effect on access control decision. According to this weighted access controlframework, a trustworthiness model for aceess request is also given. In this model, we give themeasure of trustworthiness factor to access request- by using some idea of uncertainty reasoning ofexpert system, present and prove the parallel propagation formula of request trustworthiness factoramong multiple policies, and get thefinal trustworthiness factor to decide whether authorizing. Inthis model, authorization decision is given according to the calculation of request trustworthinessfactor, which is more understandable, more suitable for real requirement and more powerfulforsecurity enhancement than traditional methods. Meanwhile the finer access control granularity isanother advantage.

Control Framework for Secure Cloud Computing

Cloud computing is touted as the next big thing in the Information Technology (IT) industry, which is going to impact the businesses of any size and yet the security issue continues to pose a big threat on it. The security and privacy issues persisting in cloud computing have proved to be an obstacle for its widespread adoption. In this paper, we look at these issues from a business perspective and how they are damaging the reputation of big companies. There is a literature review on the existing issues in cloud computing and how they are being tackled by the Cloud Service Providers (CSP). We propose a governing body framework which aims at solving these issues by establishing relationship amongst the CSPs in which the data about possible threats can be generated based on the previous attacks on other CSPs. The Governing Body will be responsible for Data Center control, Policy control, legal control, user awareness, performance evaluation, solution architecture and providing motivation for the entities involved.

Iterative optimal control based on support vector machine modeling within the Bayesian evidence framework

In the paper, an iterative method is presented to the optimal control of batch processes. Generally it is very difficult to acquire an accurate mechanistic model for a batch process. Because support vector machine is powerful for the problems characterized by small samples, nonlinearity, high dimension and local minima, support vector regression models are developed for the optimal control of batch processes where end-point properties are required. The model parameters are selected within the Bayesian evidence framework. Based on the model, an iterative method is used to exploit the repetitive nature of batch processes to determine the optimal operating policy. Numerical simulation shows that the iterative optimal control can improve the process performance through iterations.

Unified control and detection framework and its applications: a review, some new results, and future perspectives

Initiated three decades ago,integrated design of controllers and fault detectors has continuously attracted research attention.The recent development of the unified control and detection framework with an observer-based residual generator in its core gives a more general form of the previous works.Its applications to residual centred modelling of uncertain control systems,fault detection in feedback control systems with uncertainties,fault-tolerant control(FTC)as well as control performance degradation monitoring,detection and recovery are introduced.In conclusion,some future perspectives are proposed.

Research and Design on Framework of Quality Risk Control System for Livestock Products

In view of the currant status of the quality risk control of livestock products, the differences between the quality, safety and risk of the livestock products were pointed clearly; the derivative mechanism model of the quality risk was studied; the risk system of livestock products was established; and the types of controllable risk were identified. On this basis, the design principles of risk control framework were established. Then the modular system of risk control was constructed and the attributes of production system were detailed into the describable indicators of risk control based on the thrae-dimensional risks.

A novel control framework for internet based tele-robotics

Aiming at the tele-operation instability caused by time delay of interuet information transfer for internet based tele-robotics, this paper proposes a novel control framework for internet based tele-roboties, which can guarantee the non-distortion-transfer of control information and reduce the difference of action time between the local simulated virtual robot and the remote real robot. This framework is insensitive to the inherent interact time delay, and differs from other tele-robotics systems that try to use some mathematic models to describe the internet delay or take some assumptions. In order to verify the framework, a 4-DOF fischertechnik industry robot tele-operation system has been developed using the new proposed framework. Experimental results demonstrate the applicable performance of the new framework. The framework is open structured and can be applied to other general purposed tele-operation systems.

A General Framework of Reversible Data Hiding with Controlled Contrast Enhancement

This paper proposes a two-step general framework for reversible data hiding(RDH)schemes with controllable contrast enhancement.The first step aims at preserving visual perception as much as possible on the basis of achieving high embedding capacity(EC),while the second step is used for increasing image contrast.In the second step,some peak-pairs are utilized so that the histogram of pixel values is modified to perform histogram equalization(HE),which would lead to the image contrast enhancement.However,for HE,the utilization of some peak-pairs easily leads to over-enhanced image contrast when a large number of bits are embedded.Therefore,in our proposed framework,contrast over-enhancement is avoided by controlling the degree of contrast enhancement.Since the second step can only provide a small amount of data due to controlled contrast enhancement,the first one helps to achieve a large amount of data without degrading visual quality.Any RDH method which can achieve high EC while preserve good visual quality,can be selected for the first step.In fact,Gao et al.’s method is a special case of our proposed framework.In addition,two simple and commonly-used RDH methods are also introduced to further demonstrate the generalization of our framework.

基于Model/View/Controller的电子商务研究

分析了传统电子商务系统的缺陷 ,电子商务发展趋势 ,分析了M/V/C(Model/View/Controller)技术 ,提出了基于M/V/C电子商务并且分析了其体系结构及框架结构 ,以及在此框架之上构建电子商务的方法。

云控制水肥药械智能监控平台的设计与实现

随着我国农业现代化水平的提高,以水肥药械为核心的现代农业服务体系成为未来行业发展的方向。为此,采用B/S结构模式,使用Django框架,选用MySQL数据库,设计并实现了一种云控制水肥药械智能监控平台。平台拥有完善的机构、数据交互、用户和权限等管理功能,可实现水肥药械的数字化管理;嵌入了基于Bi-LSTM与LightGBM融合的参考作物蒸散量预测方法,可实现对作物灌溉的实时预测;增加了作物施肥计算公式以及施肥用药数据库,可为用户对肥、药的施用提供科学的参考依据。实际运行及性能测试结果表明:平台的架构和模块设计合理,功能较全面和灵活,可有效满足设施园区对于水肥药械的管理需求,推动现代化农业发展。

基于.Net Micro Framework的电动汽车充电桩控制系统的设计

针对电动汽车充电桩控制系统开发周期长、扩展能力差的问题,设计了一种基于.Net Micro Framework的电动汽车充电桩控制系统。本系统基于Cortex-M3内核的开发板,采用了模块化设计原则,详细阐述了.Net Micro Framework在电动汽车充电桩控制系统中的开发流程和功能模块设计。本系统已在山东临沂焦庄、青岛薛家岛充换电站的充电桩上运行使用,运行结果表明该系统扩展能力强、开发成本低,运行更加稳定可靠。

基于Require.js+koa2+Typescript+Routing-controllers框架设计与实现

本框架设计采用Require.js实现JS文件的模块化和异步加载。以koa2作为后端API接口框架的核心底层引擎。通过typescript强类型提高开发效率,提升框架的稳定性和健壮性。通过routing-controllers装饰器设计,降低代码的冗余量,提高代码的可维护性和可读性。从而为全栈工程师提供一个开箱即用的开源框架,同时也为学习者提供一定的理论依据。

Modeling of combined Bayesian networks and cognitive framework for decision-making in C2

The command and control（C2） is a decision-making process based on human cognition,which contains operational,physical,and human characteristics,so it takes on uncertainty and complexity.As a decision support approach,Bayesian networks（BNs） provide a framework in which a decision is made by combining the experts＇ knowledge and the specific data.In addition,an expert system represented by human cognitive framework is adopted to express the real-time decision-making process of the decision maker.The combination of the Bayesian decision support and human cognitive framework in the C2 of a specific application field is modeled and executed by colored Petri nets（CPNs）,and the consequences of execution manifest such combination can perfectly present the decision-making process in C2.

Type Design and Behavior Control for Six Legged Robots

The research on legged robots attracted much attention both from the academia and industry. Legged robots are multi-input multi-output with multiple end-e ector systems. Therefore,the mechanical design and control framework are challenging issues. This paper reviews the development of type synthesis and behavior control on legged robots; introduces the hexapod robots developed in our research group based on the proposed type synthesis method. The control framework for legged robots includes data driven layer,robot behavior layer and robot execution layer. Each layer consists several components which are explained in details. Finally,various experiments were conducted on several hexapod robots. The summarization of the type synthesis and behavior control design constructed in this paper would provide a unified platform for communications and references for future advancement for legged robots.

An Improved Robust Model Predictive Control Approach to Systems with Linear Fractional Transformation Perturbations

In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws instead of a single one, the control performance can be improved and the region of attraction can be enlarged compared with the existing model predictive control （MPC） approaches. Moreover, a synthesis approach of MPC is developed to achieve high performance with lower on-line computational burden. The effectiveness of the proposed approach is verified by simulation examples.

Ensuring Security, Confidentiality and Fine-Grained Data Access Control of Cloud Data Storage Implementation Environment

With the development of cloud computing, the mutual understandability among distributed data access control has become an important issue in the security field of cloud computing. To ensure security, confidentiality and fine-grained data access control of Cloud Data Storage (CDS) environment, we proposed Multi-Agent System (MAS) architecture. This architecture consists of two agents: Cloud Service Provider Agent (CSPA) and Cloud Data Confidentiality Agent (CDConA). CSPA provides a graphical interface to the cloud user that facilitates the access to the services offered by the system. CDConA provides each cloud user by definition and enforcement expressive and flexible access structure as a logic formula over cloud data file attributes. This new access control is named as Formula-Based Cloud Data Access Control (FCDAC). Our proposed FCDAC based on MAS architecture consists of four layers: interface layer, existing access control layer, proposed FCDAC layer and CDS layer as well as four types of entities of Cloud Service Provider (CSP), cloud users, knowledge base and confidentiality policy roles. FCDAC, it’s an access policy determined by our MAS architecture, not by the CSPs. A prototype of our proposed FCDAC scheme is implemented using the Java Agent Development Framework Security (JADE-S). Our results in the practical scenario defined formally in this paper, show the Round Trip Time (RTT) for an agent to travel in our system and measured by the times required for an agent to travel around different number of cloud users before and after implementing FCDAC.

Construction of cyclodextrin-based organic frameworks with adjustable size:Enhanced the physicochemical stability and controlled release characteristics of apigenin

The poor physicochemical stability and bioavailability of apigenin were main factors that limited its application in the food industry.Theγ-cyclodextrin-metal-organic frameworks(γ-CD-MOFs)were prepared using polyethylene glycol(PEG)as surfactants to solve these issues.The size ofγ-CD-MOFs,ranging from nanometer to micrometer dimensions,could be controlled by using PEG with different molecular weights.Theγ-CD-MOFs based on PEG 10000(molecular weight of 10000)had a small pore size(1.58 nm)and high BET surface area(810.15 m^(2)/g),leading to a high encapsulation efficiency(74.23%)and loading capacity(41.17%)for apigenin.Apigenin interacted withγ-CD-MOFs through van der Waals forces,hydrophobic interactions and hydrogen bonding,but did not affect the inherent crystallinity ofγ-CD-MOFs.Furthermore,γ-CD-MOF-10000 protected apigenin better against UV light and temperature,resulting in better anti-cancer properties and controlled release efficiency(79.89%).This strategy of constructingγ-CD-MOFs nanocarriers with tunable size may open new possibilities for hydrophobic drug applications.

Cloud-Based Access Control to Preserve Privacy in Academic Web Application

Emerging cloud computing has introduced new platforms for developing enterprise academic web applications, where software, platforms and infrastructures are published to the globe as services. Software developers can build their systems by multiple invocations of these services. This research is devoted to investigating the management and data flow control over enterprise academic web applications where web services and developed academic web application are constructing infrastructure-networking scheme at the application level. Academic web services are invoked over http port and using REST based protocol;thus traditional access control method is not enough to control the follow of data using host and port information. The new cloud based access control rules proposed here are to be designed and implemented to work at this level. The new proposed access control architecture will be a web service gateway, and it published itself as a service (SaaS). We used three case studies to test our moodle and then we apply JSON parsers to perceive web service description file (WSDL file) and supply policies according to data are to be allowed or denied based on user roll through our parsing.

A Multi-Factor Authentication-Based Framework for Identity Management in Cloud Applications

User’s data is considered as a vital asset of several organizations.Migrating data to the cloud computing is not an easy decision for any organization due to the privacy and security concerns.Service providers must ensure that both data and applications that will be stored on the cloud should be protected in a secure environment.The data stored on the public cloud will be vulnerable to outside and inside attacks.This paper provides interactive multi-layer authentication frameworks for securing user identities on the cloud.Different access control policies are applied for verifying users on the cloud.A security mechanism is applied to the cloud application that includes user registration,granting user privileges,and generating user authentication factor.An intrusion detection system is embedded to the security mechanism to detect malicious users.The multi factor authentication,intrusion detection,and access control techniques can be used for ensuring the identity of the user.Finally,encryption techniques are used for protecting the data from being disclosed.Experimental results are carried out to verify the accuracy and efficiency of the proposed frameworks and mechanism.The results recorded high detection rate with low false positive alarms.

松辽盆地西缘构造带构造格架、演化及油气资源潜力

松辽盆地西缘构造带是研究松辽盆地形成演化的关键地带,但目前关于该构造带的构造格架、活动历史、控盆特征等仍不清晰,构造带深部物质架构及中—新生代构造演化的精细厘定为解决这一科学问题提供了新的证据。松辽盆地西缘地区布格重力异常与综合地球物理剖面特征指示,松辽盆地西缘构造带为区域上带状展布的超壳深大构造带。通过对综合构造变形带的产状、性质、运动学等资料分析,提出松辽盆地西缘构造带东西分带、倾向相背的“两带八字形”构造格架。依据构造带发育的基底背景、构造样式、地球物理特征等差异,建立了南北分段的“四段式”展布构架。在此基础上,结合区域构造演化、变形带构造解析与40Ar/39Ar构造年代学等资料,恢复了晚三叠世、中晚侏罗世、早白垩世中期、晚白垩世中期、古新世—渐新世和新近纪—更新世6期中—新生代构造活动年代格架。结合构造带的控盆作用指出,外盆带控制的中侏罗世和早白垩世中期沉积盆地是油气资源勘查的重要选区,为中国东北地区新层系油气资源勘查提供了新依据。