摘要：In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub- stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci- pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.

摘要：The H_∞ performance analysis and controller design for linear networked control systems(NCSs) are *** NCSs are considered a linear continuous system with time-varying interval input delay by assuming that the sensor is time-driven and the logic Zero-order-holder(ZOH) and controller are *** on this model,the delay interval is divided into two equal subintervals for H_∞ performance *** improved H_∞ stabilization condition is obtained in linear matrix inequalities(LMIs) framework by adequately considering the information about the bounds of the input delay to construct novel Lyapunov–Krasovskii functionals(LKFs).For the purpose of reducing the conservatism of the proposed results,the bounds of the LKFs differential cross terms are properly estimated without introducing any slack matrix ***,the H_∞ controller is reasonably designed to guarantee the robust asymptotic stability for the linear NCSs with an H_∞ performance level γ.Numerical simulation examples are included to validate the reduced conservatism and effectiveness of our proposed method.

摘要：LCO_2(liquid CO_2) can absorb heat and release latent heat via phase transition, which can provide considerable cooling energy and effectively solve the problem of thermal damage in deep coal mining processes. A LCO_2 cycle refrigeration system is designed to continuously cool down the working face in a mine, and CO_2 is cyclically utilized. Additionally, LCO_2 is used not only as a cold source but also to prevent spontaneous combustion of coal in the gob. COMSOL Multiphysics simulation software is used to characterize the thermal performance of the heat exchange system, where the heat transfers between the CO_2 and the airflow. For a LCO_2 consumption of 13.54 m^3/h, the temperature of the airflow in the tunnel decreases by 7.72°C, and the cooling volume of the system reaches 142.99 kW/h; the cooling volume provides a latent heat release of 46.68 k W/h. The main influencing factors of the refrigeration system, such as ventilation flux, LCO_2 flow, LCO_2 temperature and initial tunnel temperature, are also analyzed quantitatively through the software. The temperature of the steady airflow in the tunnel is proportional to the square of the local fan ventilation flux, and it decreases linearly with an increase in the LCO_2 flow but increases with both the temperature of the LCO_2 and the initial temperature in the tunnel. When the temperature difference between the LCO_2 and wind increases, the heat exchange between the CO_2 and wind intensifies, and the cooling volume increases.

摘要：A novel fiber Bragg grating （FBG） rain gauge is proposed in this paper to achieve high precision rainfall measurement. One core sensitive FBG, a temperature compensation FBG and a mechanical transition system construct this novel FBG rain gauge. Sensing principle of this FBG rain gauge is explained in detail, and its theoretical calculation model is also established, which shows that the relationship between center wavelength of sensitive FBG and external rainfall has very good linearity. To verify its detection performance, the calibration experiment on one prototype of this FBG rain gauge is carried out. After experiment data analysis, the detection precision of this FBG rain gauge is 15.4/.tm which is almost two orders of magnitude higher than that of the existing rainfall measurement device. The experimental data confirm that this FBG rain gauge can achieve rainfall measurement with high precision.

摘要：In order to realize safe and accurate homing of parafoil system,a multiphase homing trajectory planning scheme is proposed according to the maneuverability and basic flight characteristics of the *** this scenario,on the basis of geometric relationship of each phase trajectory,the problem of trajectory planning is transformed to parameter optimizing,and then auxiliary population-based quantum differential evolution algorithm(AP-QDEA)is applied as a tool to optimize the objective function,and the design parameters of the whole homing trajectory are *** proposed AP-QDEA combines the strengths of differential evolution algorithm(DEA)and quantum evolution algorithm(QEA),and the notion of auxiliary population is introduced into the proposed algorithm to improve the searching precision and *** simulation results show that the proposed AP-QDEA is proven its superior in both effectiveness and efficiency by solving a set of benchmark problems,and the multiphase homing scheme can fulfill the requirement of fixed-points and upwind landing in the process of homing which is simple in control and facile in practice as well.

摘要：This paper investigates the H∞ filtering problem for a class of linear continuous-time systems with both time delay and saturation. Such systems have time delay in their state equations and saturation in their output equations, and their process and measurement noises have unknown statistical characteristics and bounded energies. Based on the Lyapunov-Krasovskii stability theorem and the linear matrix inequalities （LMIs） technique, a generalized dynamic filter architecture is proposed, and a filter design method is developed. The linear H∞ filter designed by the method can guarantee the H∞ performance. The parameters of the designed filter can be obtained by solving a kind of LMI. An illustrative example shows that the design method proposed in this paper is very effective.

摘要：Dermal substitutes have provided a template for the regeneration and reconstruction of the ***,the healed skin tissue often exhibits abnormal morphology and functionality,including scarring and *** this study,a composite bioink composed of methacrylated gelatin(GelMA)and chitosan oligosaccharide(COS)was proposed for printing a dermal scaffold using digital light processing(DLP)*** GelMA/COS bioink exhibited suitable porosity,swelling,degradation rate,and mechanical *** inclusion of COS demonstrated antibacterial effects against both Gram positive and Gram-negative bacteria,while simultaneously fostering the proliferation of human dermal fibroblasts(HDFs).Additionally,the application of COS could effectively reduce the expression levels of fibrosis-related genes,such as collagen I,collagen III,and fibronectin *** three-dimensionally printed cell-laden dermal scaffold exhibited excellent shape fidelity and high cellular viability,facilitating the extension of HDFs along the scaffold and the simultaneous secretion of extracellular matrix ***,the HDF-laden dermal scaffold transplanted into full-thickness skin defect sites in nude mice was shown to accelerate wound closure,reduce inflammation,and improve wound ***,the DLP-printed dermal scaffold provides an appealing approach for effectively treating full-thickness skin defects in clinical settings.

摘要：With a growing population, an increasing number of petrochemical facilities are built with larger capacity and more complexity, which pose a great risk to assets, community and environment. The value of inherently safer design is recognized with time by all stakeholders, and an effective tool is needed to evaluate and compare inherent safety of alternative technologies. This study developed a safety index to evaluate existing technologies for their safety levels and guide inherently safer design. The Integrated Risk-based Safety Index(IRSI) was developed based on a comprehensive review of petrochemical processes, incident cases from Sinopec and US Chemical Safety Board, and existing safety index systems. The IRSI included all major hazards, including fire, explosion,toxic release, dust explosion, physical explosion, and runaway. Also, the integrated life cycle approach considered chemical hazards, equipment failure rates and safety measures in this risk-based index. Advanced modeling techniques, PHAST simulation and Neural Network, were used in the development of three novel sub-indices in the projects, fire, explosion and toxic release. The index system could be easily incorporated into a user friendly tool for the ease of application. A case study of hydrogen dioxide was conducted using the IRSI, which showed its capability for evaluating the safety level of process facilities.

摘要：Plenty of dams in China are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and *** dam safety inspection remotely operated vehicle(DSIROV) is designed to solve these problems which can be equipped with many advanced sensors such as acoustical,optical and electrical sensors for underwater dam inspection.A least-square parameter estimation method is utilized to estimate the hydrodynamic coefficients of DSIROV,and a four degree-of-freedom(DOF) simulation system is *** architecture of DSIROV's motion control system is introduced,which includes hardware and software *** hardware based on PC104 BUS,uses AMD ELAN520 as the controller's embedded CPU and all control modules work in VxWorks real-time operating *** flow of the motion system of DSIROV,automatic control of dam scanning and dead-reckoning algorithm for navigation are also *** reliability of DSIROV's control system can be verified and the control system can fulfill the motion control mission because embankment checking can be demonstrated by the lake trials.

摘要：A Natural Ecological Wastewater Treatment System （NEWTS） is usually built on natural terrain with necessary topography modification to improve water flowing route and pattern, and then the topography modified NEWTS should also have a reasonable water storage volume and hydraulic retention time so as to achieve the anticipated water purification effect. In this study, the dynamic mesh technique based on the finite element method and element storativity coefficients was presented to develop a two-dimensional hydrodynamic and water quality model, which was used to optimize the design of NEWTS under the dynamic land-water boundary due to various water storage volume. The models were employed in the optimized design of NEWTS from a large abandoned coal mine, which purifies the polluted water flowing into a large water storage lake, as part of the East Route South-to-North Water Transfer Project in China. Specifically, the natural topography modification scheme was presented, and further, a reasonable water storage volume and hydraulic residence time was obtained, based on the reasonable estimation of roughness coefficient and pollutant removal rate of the NEWTS with phragmites communis.