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This article investigates the stabilization of stochastic highly non-linear coupled systems (SHNCSs) with multiple time delays by using periodically intermittent control (PIC). It is worth noting that coefficients in SHNCSs dissatisfy the linear growth condition, which weakens the previous stability conditions. In addition, PIC and multiple time delays are first introduced into the study of highly nonlinear systems, which leads to the existing methods being inapplicable to investigate the stability of SHNCSs with multiple time delays. Therefore, a novel Halanay-type differential inequality is established, which can be employed to deal with highly nonlinear systems with PIC. Based on the Lyapunov method, the graph theory, and the novel differential inequality, SHNCSs with multiple time delays are first studied, and stability criteria are presented. Next, the theoretical results can be applied to modified FitzHugh–Nagumo models. At last, a numerical example is presented to show the effectiveness of our results.

This study aimed to evaluate the feasibility and safety of a novel stent manufactured by metal injection molding (MIM) in clinical practice through animal experiments. Vessel stents were prepared using powder injection molding technology to considerably improve material utilization. The influence of MIM carbon impurity variation on the mechanical properties and corrosion resistance of 316L stainless steel was studied. In vitro cytotoxicity and animal transplantation tests were also carried out to evaluate the safety of MIM stents. The results showed that the performance of 316L stainless steel was very sensitive to the carbon content. Carbon fluctuations should be precisely controlled during MIM. All MIM stents were successfully implanted into the aortas of the dogs, and the MIM 316L stents had no significant cytotoxicity. The novel intravascular stent manufactured using MIM can maintain a stable form and structure with fast endothelialization of the luminal surface of the stent and ensure long-term patency in an animal model. The novel intravascular stent manufactured using MIM demonstrates favorable structural, physical, and chemical stability, as well as biocompatibility, offering promising application in clinical practice.

Despite the success in decreasing varicella-related disease burden, live-attenuated Oka vaccine strain of varicella-zoster virus (vOka) remains neuro-virulence and may establish latency and reactivate, raising safety concerns. Here we aimed to evaluate the safety and immunogenicity of a skin- and neuro-attenuated varicella vaccine candidate (v7D).

To identify the coumarins constituents in Cnidium monnieriand classify ten samples into three groups and this helpful chemical information could be used for the further pharmacological and clinical study on C. monnieri.

Patients and doctors often have questions about the equivalence of traditional and machinery decoctions. In this article, using Da-cheng-qi Decoction (DCQD) as a model of formula, traditional decoction (TD), machinery decoction under high pressure (MDHP), and machinery decoction under normal pressure (MDNP) were compared.

There has been a significant increase in the publication of clinical practice guidelines (CPGs) for respiratory diseases in China. However, little is known about the quality and potential impacts of these CPGs. Our objective was to critically evaluate the quality of Chinese CPGs for respiratory diseases that were published in peer-reviewed medical journals.

This paper studies the stability analysis of discrete time-varying system with parameter uncertainties and disturbances. The system under consideration is subject to time-varying non-bounded parameter uncertainties in both the state and measured output matrices. To facilitate the stability analysis, the T-S fuzzy model is employed to represent the discrete-time nonlinear system. A fuzzy observer is used to guarantee the Lyapunov stability of the closed-loop system and reduces the effect of the disturbance input on the controlled output to a prescribed level for all admissible uncertainties. The control and observer matrices can be obtained by directly solving a set of linear matrix inequality (LMI) via the existing LMI optimization techniques. Finally, an example is provided to demonstrate the effectiveness of the proposed approach.

AbstractThe thermooxidative degradation of natural rubber (NR) coagulated by microwave radiation (NR-m) was investigated by thermogravimetry (TG) analysis, and compared with NR coagulated by acid (NR-a). It was found that the degradation process is not a one-step reaction, the main degradation process occurs at 300–400ºC, and the equilibrium degradation temperatures of NR-m are higher than those of NR-a. Different methods were used to find the most probable kinetic model and the Arrhenius para­meters (activation energy Eand preexponential factor A) for the main stage of thermooxidative degradation of NR-m. The results show that the values of Eand A, obtained from the Coats-Redfern method, are highly variable with the kinetic model chosen and the heating rate (β), and the apparent activation energy (E0) when βapproaches zero for the Dntype kinetic model is in the range of 96.7–106.4 kJ ∙ mol-1. The mean values of E, calculated by the Friedman and Flynn-Wall-Ozawa (FWO) methods, are 113.8 and 83.3 kJ ∙ mol-1, respectively, suggesting Ein the range of 83.3–113.8 kJ ∙ mol-1. Comparison of these two ranges indicates the most probable kinetic model to be Dntype kinetic models, corresponding to a diffusion-controlled mechanism.

In the context of data integration on the web, traditional data integration system lacks scalability, flexibility, is no longer adequate. A novel data integration architecture, UQSIQ, is proposed, which achieves web-scale data integration. Key components in the system are introduced. UQSIQ maps user query schema to a suitable domain, selects web databases, querys and then ranks results. Key techniques, domain mapping and user query schema matching, to handle the scale and heterogeneity of structured web data are described.

A water soluble binder system is used to prepare Ti-6Al-4V and NiTi pre-alloyed powder feedstock. The binder dissolution and transport kinetics through the porous powder skeleton are studied for various powder morphologies and powder loadings from 60 to 69.5 vol.%. The binder removal behaviours are evaluated with different debinding time intervals. The focus of this work is to investigate the influences of shaping pressure, specimen thickness and water bath temperature on the binder extraction behaviour.

The dynamic tension of synchronous belt and pulleys forces are obtained by analyzing the dynamic characteristics of timing drive system of a diesel based on muti-body dynamics. The effects of crankshaft speed fluctuation and other excitations on the dynamics characteristics of synchronous belt are illustrated. After the analysis, it is found that crankshaft speed fluctuation has a great influence on the linear and transversal vibrations of synchronous belt. Comparing the simulation results of the original timing system and the one optimized, it is found that the modal frequency of synchronous belt depends on its span. Therefore it is important to control the span of belt and arrange the tensioner pulley properly for timing system design.

The 3D injection discrete element model of blade injection part is constructed. PFC3D is used to program for filling simulation and analysis. The simulation result shows that there is anisotropy and filling in injection direction first. There is difference between results by discrete element and by Moldflow software. There is large contact stress in reverse direction in sharp angle region and it is filled at last. The injection test result shows that the injection discrete element model is feasible.

A novel Adaptive Fuzzy Sliding Mode Control (AFSMC) methodology is proposed in this paper based on the integration of Sliding Mode Control (SMC) and Adaptive Fuzzy Control (AFC).To get rid of the chattering and the bound of uncertainty, an adaptive fuzzy logic system design method introduced for the switching gain is proposed. The main advantage of our proposed methodology is that the nonlinear systems are unknown and no knowledge of the bounds of parameters, uncertainties and external disturbance are not required in advance.the design for the switching gain which will relax the requirement for the bound of uncertainty can ensure stability. The simulation results illustrate the effectiveness of the method.

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} In the present study, effect of sintering temperature and atmosphere on corrosion behavior of 316L stainless steel specimens manufactured by metal injection molding (MIM) process were investigated. Sintering experiments were carried out at 1320°C, 1370°C and 1375°C under various sintering atmospheres, i.e. Ar+H2, Ar, N2+H2 or N2. The corrosion behavior of as-sintered specimens was studied by weight loss immersion test in 5%HCl solution. The results indicated that a better corrosion resistance was accompanied higher density, finer and rounder surface pores. The specimens sintered under Ar+H2 atmosphere at 1370°C had little susceptibility to intergranular corrosion.

SiC/Al composites with high reinforcement content were fabricated by pressure infiltration of aluminum alloy into porous SiC preform obtained by powder injection molding using a bimodal powder mixture. The influence of powder loading and particle size on the thermo-physical properties of the prepared composites was investigated. The results indicate that the thermal conductivities (TC) increases and coefficients of thermal expansion (CTE) decreases with increasing powder loading and particle size of the coarse powders in the bimodal powder system. The TCs are below the estimated value based on Hasselman-Johnson model, mainly due to the residual pores and the irregular particle shape. The CTEs of the composites increase with increasing temperature from 100°C to 400°C, and the increasing rates vary at different temperature ranges. Deep cooling in liquid nitrogen is effective to bring dislocations in the matrix and thus reduces the CTEs.

Hoteliers in Taiwan re-manifest the prosperity of motels originally seen in the U.S. Most Taiwanese associate motels with sex, yet this negative image has not hindered the development of motels in Taiwan. Hoteliers spend efforts to be creative and daring in their managements to meet consumers' needs, and are aggressive in making hotels refined and casual so that they are no longer merely spaces to overnight. Therefore, this research investigates whether criteria such as location, facilities, service, and prices serve to actually meet the needs of consumers. We do so by sending out questionnaires to consumers who have visited motels, and inquire also about the difference of perceptions towards services and facilities provided by hoteliers. Further, we investigate overnighters' intention of motel stays and their demographics. Our analysis tools include confidence and validity levels in SPSS 14.0, and independent T sampling, etc. Our Cronbach's value has reached above 0.8 in confidence level. Through literature review and the analysis done on the 272 valid questionnaires returned, we found that the boutique motels are no longer ones situated near main highways that enjoy transportation convenience and high level of entertainment when nearby metropolises.Through literature review and the receipt of the valid 272 questionnaires returned, we find in our analysis that today's boutique motels are no longer merely for the purpose overnights and situated at main roads, but rather possess high convenience and entertainment and casual qualities in downtown areas. From categories based on Placement Attachment, we found that consumers go to motels no longer for resting and overnighting, but rather, for romantic dates and get-togethers with friends. They are influenced by outside stimulation such as magazine recommendations, TV report coverage, and internet introductions, all serving to raise their interests in and impressions of motels, so as to increase their intentions to overnight in motels. Our Analysis of Pursuits of New sensation further proves that the higher one scores on the pursuits of new sensation indicates a difference preference in motels facilities.

The paper presents the result of an experimental investigation on the fabrication of Al/SiC composites with high volume fraction of SiC particles by pressure infiltration of liquid aluminum into preforms prepared by powder injection molding (PIM). To obtain the required high particle volume fraction, SiC powders with a bimodal particle size distribution were used. The influence of powder loading and particle size on the bending strength of the prepared composites has been investigated. It is demonstrated that pressure infiltration permits to achieve high relative densities for the composites (i.e. 98.8%). The microstructure studies revealed a uniform distribution of SiC particles in the composites without interface reactions between the particles and the aluminum matrix. The bending strength increases with increasing powder loading and decreasing particle size of the coarse powders in the bimodal powder system.

In the present study, the effect of injection temperature, velocity and delay time on the interface morphology of the co-injection molded plates was studied. The results showed that the core penetration parallel to the flow direction becomes less as the skin injection velocity and temperature increases and delay time decreases. Among the parameters, temperature was the most significant in affecting the interface morphology, followed by delay time, while injection velocity seemed to play no significant role. The results were analyzed by taking account of rheological properties of the two feedstocks. Calculations and comparisons of viscosity ratios encountered in experiments were made. It was demonstrated the differences in the rheological properties of the metal feedstocks involved are key factors in determining the interface morphology of the molded parts.

Seroprevalence data suggest that a third of the world's population has been infected with the hepatitis E virus. Our aim was to assess efficacy and safety of a recombinant hepatitis E vaccine, HEV 239 (Hecolin; Xiamen Innovax Biotech, Xiamen, China) in a randomised, double-blind, placebo-controlled, phase 3 trial.

An experimental study of co-injection molding which involves sequential injection of dissimilar metal feedstocks into a mold has been carried out. The effect of skin temperature and injection velocity on the material distribution of co-injection molded plates has been studied. It was found that the molding temperature was important in controlling skin-core distribution, while injection velocity seemed to play no significant role. The experimental results were analyzed by taking account of the relative viscosity of the two melts. It was demonstrated that the differences in rheological properties of the metal feedstocks involved are the primary variable determining the phase distribution of the molded parts.

The apparent morphologies of packet martensite in eight high carbon steels were researched by using optical microscope, scanning electron microscope, and transmission electron microscope. It was found that the apparent morphologies, substructures, and habit plane of packet martensite in high carbon steels are entirely different from that in low carbon steels the substructures of packet martensite in high carbon steels possess fully twinned structure, while the substructures of individual coarse martensite plates in these steels bear both fully and partially twinned structures. The formation reason for apparent morphologies, substructures and two habit planes (i. e, {111}rand {225}r) of high carbon martensite were discussed in detail.

The apparent morphologies of packet martensite in eight high carbon steels were researched by using optical microscope, scanning electron microscope, and transmission electron microscope. It was found that the apparent morphologies, substructures, and habit plane of packet martensite in high carbon steels are entirely different from that in low carbon steels; the substructures of packet martensite in high carbon steels possess fully twinned structure, while the substructures of individual coarse martensite plates in these steels bear both fully and partially twinned structures. The formation reason for apparent morphologies, substructures and two habit planes (i. e, {111} r, and {225} r) of high carbon martensite were discussed in detail.

This paper gives an introduction to a new computer program – Dynasol (DynaSolver), a package of quantum dynamics program with graphical user interface (GUI). Dynasol is built on modern computational methods in quantum reaction dynamics and is integrated with graphical interface and visualization tools for X-window environment. The basic structure and instruction of using Dynasol are presented with simple examples. The available applications of Dynasol and the instructions on how to download and install the program are also provided.

The granular model which is fit for discontinuous bodies is applied to powder injection molding. The powder is regarded as discrete particles which are immersed into binder. The powder three-dimensional flowing in powder injection molding has been simulated based PFC. The results show that the filling rate of granulars is anisotropy and injection molding is always filled in the central region of cavity where resistance is smaller. But the angular area where resistance is large often filled be the end, even if it is close to the center of pressure.