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1.
Lack of hydrogen refueling stations (HRSs) has hindered the diffusion of hydrogen fuel cell vehicles (HFCVs) in the Chinese transport market. By combining the agent-based model (ABM) and the experience weighted attraction (EWA) learning algorithm, this paper explores the impact of government subsidy strategy for HRSs on the market diffusion of HFCVs. The actions of the parties (government, HRS planning department and consumers) and their interactions are taken into account. The new model suggests dynamic subsidy mode based on EWA algorithm yields better results than static subsidy mode: HFCV purchases, HRS construction effort, total number of HRSs and expected HRS planning department profits all outperform static data by around 27%. In addition, choosing an appropriate initial subsidy strategy can increase the sales of HFCVs by nearly 40%. Early investment from government to establish initial HRSs can also increase market diffusion efficiency by more than 76.7%.  相似文献   
2.
A complete characterization of the stability boundary of an asymptotically stable equilibrium point in the presence of type-k saddle-node non-hyperbolic equilibrium points, with k ≥ 0, on the stability boundary is developed in this paper. Under the transversality condition, it is shown that the stability boundary is composed of the stable manifolds of the hyperbolic equilibrium points on the stability boundary, the stable manifolds of type-0 saddle-node equilibrium points on the stability boundary and the stable centre and centre manifolds of the type-r saddle-node equilibrium points with r ≥ 1 on the stability boundary. This characterization is the first step to understanding the behaviour of stability regions and stability boundaries in the occurrence of saddle-node bifurcations on the stability boundary.  相似文献   
3.
Adults of Tribolium castaneum (Herbst) and Rhyzopertha dominica (F.) biosynthesize aggregation pheromones 4,8-dimethyldecanal and dominicalure-1/dominicalure-2, respectively. These pheromones are commonly used independently, and their simultaneous use has not been adequately studied. Furthermore, information on trapping flying R. dominica in pheromone traps is minimum. Therefore, the objectives were to evaluate distance of attraction of T. castaneum and R. dominica adults to traps having both pheromones, and height of R. dominica adult attraction to traps with its pheromone lure alone. In first experiment, both pheromones were deployed simultaneously inside a commercial pitfall trap. One-month-old 20 T. castaneum and R. dominica adults were released every 30 cm from the pheromone trap. The adults trapped were recorded at 4 and 24 h following their release. Adults of both species released were captured in higher percentages at 24 h than 4 h. At 30 cm distance, these values were 45.5% for T. castaneum and 10–12% for R. dominica for 24 h whereas they were 40.5% for T. castaneum and 5–7.5% for R. dominica following 4 h exposure. The maximum trap capture was at 30 cm for T. castaneum and 30–60 cm for R. dominica. In second experiment, a trap with two rubber septa containing dominicalure-1 and dominicalure-2 was placed at different heights inside cage, and R. dominica adults were released at the bottom. In each experiment, four replicates were tested. After 24 h, flying R. dominica adults were captured in progressively lower percentages as trap height increased up to 40 cm above the bottom of cage. Trap heights above 10 cm exhibited decreased trap capture of R. dominica compared to those at 3 cm. We conclude that simultaneous use of both aggregation pheromones better facilitates trapping of walking T. castaneum and R. dominica. Traps above 10 cm show decreased captures of flying R. dominica.  相似文献   
4.
This paper investigates PID control design for a class of planar nonlinear uncertain systems in the presence of actuator saturation. Based on the bounds on the growth rates of the nonlinear uncertain function in the system model, the system is placed in a linear differential inclusion. Each vertex system of the linear differential inclusion is a linear system subject to actuator saturation. By placing the saturated PID control into a convex hull formed by the PID controller and an auxiliary linear feedback law, we establish conditions under which an ellipsoid is contractively invariant and hence is an estimate of the domain of attraction of the equilibrium point of the closed-loop system. The equilibrium point corresponds to the desired set point for the system output. Thus, the location of the equilibrium point and the size of the domain of attraction determine, respectively, the set point that the output can achieve and the range of initial conditions from which this set point can be reached. Based on these conditions, the feasible set points can be determined and the design of the PID control law that stabilizes the nonlinear uncertain system at a feasible set point with a large domain of attraction can then be formulated and solved as a constrained optimization problem with constraints in the form of linear matrix inequalities (LMIs). Application of the proposed design to a magnetic suspension system illustrates the design process and the performance of the resulting PID control law.   相似文献   
5.
The objective of this study is to determine if men would follow the “red effect” when choosing colors for women to wear on a date, and also to determine if the colors that men would wear when going on a date would be the same as the colors that females (their date) would wish them to wear. A set of psychophysical data was generated from this experiment, where participants were asked to rank a set of 10 colored samples based on preference for each question asked. There were three different sets of colored samples. The set of colored samples given to the participant depended on the question. A total of five questions were asked. Scaling analysis was done on the data to organize a set of items according to preferences providing values, an interval scale (Z values), that correspond to the relative perceptual differences among the stimuli. The Z values were graphed to show the general preference of colors for women to wear, and the preference of colors for men to wear. A Spearman's rank-order correlation coefficient (SRCC) was calculated comparing each individual's rank order with the mean rank order for that specific question. An average Spearman's rank order was calculated for each question and each gender in order to determine the variability in answers. Scaling results indicate that men follow the “red effect,” but women preferred to wear other colors such as turquoise, blue, or yellow depending on the outfit. Males and females agreed that no matter the colored bottoms (denim or black), blue was the preferred color top for men to wear. SRCC results showed a lot of variability between individual answers and the mean answer indicating that participants' rankings did not necessarily agree with general color preferences presented in the scaling analysis. While scaling analysis might suggest certain color preferences such as men following the “red effect” and women preferring to wear blue, the poor correlation found using SRCC between the individual answers and the mean rank orders suggests that color preferences for each individual are inherently unique.  相似文献   
6.
Aluminum phosphate (AlPO4) is a promising oxidation-resistant and weak interface for ceramic-matrix composites. In this research, AlPO4 coating was deposited on mullite fibers by an improved liquid-phase method based on electrostatic attraction. A cationic polyelectrolyte, polyethylenimine (PEI), was used for surface modification of mullite fibers. The formation process, phase evolution and microstructure of the coating were studied. The zeta potential of AlPO4 particles, PEI-adsorbed AlPO4 particles, and PEI-adsorbed mullite particles was characterized to find the proper pH value for improving electrostatic attraction. The obtained AlPO4 coating was porous and continuous, whose thickness could be controlled by multiple coating cycles. The relatively low calcination temperature (600 or 1000 °C) was a useful heat treatment method to develop bonding between coating and fiber as well as reduce the fiber strength degradation. The phase transformations of AlPO4 have little volume change, and cristobalite AlPO4 is thermal compatible with mullite. Therefore, the coating structure was preserved after calcining at 1200 °C. The technique is also applicable for other fibers contained mullite phase to fabricate high-performance AlPO4 coated mullite/mullite composites.  相似文献   
7.
A methodology is presented for assessing the expected loss of human lives due to the structural damage, failure of contents and non-structural components inside buildings during earthquakes. This approach estimates human life losses considering whether the structure collapses (partial or totally) or not. Entrapment and entrapment fatality rates are calculated using available data from worldwide literature and newspapers of 50 collapsed buildings, which information is reasonably reliable. We apply this methodology to one example of a five-floor RC frame building of typical office occupancy. Vulnerability functions are presented relating the intensity of the earthquake to the loss of human lives inside buildings, considering different times of occurrence of the earthquakes: daytime, commuting time and nighttime. Uncertainties in all parts of the process are very large, but they are formally addressed and taken into account. This methodology may improve the risk assessment for insurances purposes, optimisation of the cycle of life, mitigation strategies, risk control and tolerable risk.  相似文献   
8.
Herein, the poorly water-soluble drug, Tamoxifen (Tmx), was loaded in the amphipathic matrix of human serum albumin (HSA) nanoparticles by a modified desolvation method. In order to enhance the drug loading (DL) and drug entrapment efficiency (DEE) (<2% and 10%, respectively), ultrasonication of Tmx-HSA mixture was performed prior to desolvation process. Tmx loading and entrapment efficiency were optimized by employment of the response surface methodology (RSM)-central composite design (CCD) of experiments. Under the optimum conditions of 1.59 mg Tmx/ml concentration, 7.76 pH and 5 h incubation of HSA-Tmx, the DL of 6.7% and DEE of 74% are achievable. Particles with the average size of 195 nm, zeta potential of −21 mV and polydispersity index of 0.09 were produced under these conditions. A more sustained Tmx release behavior was observed from polyethylene glycol (PEG) conjugated nanoparticles in comparison to the non-PEGylated ones. The short-term stability investigation showed no alteration in physicochemical properties of nanoparticles at 4 and 37 °C, but small increase in nanoparticles size was observed after three months of storage at room temperature. This is the first report for efficient production of a Tmx delivery system based on HSA nanoparticles.  相似文献   
9.
This article examines the asymptotic inference for AR(1) models with a possible structural break in the AR parameter β near the unity at an unknown time k0. Consider the model yt = β1yt − 1I{tk0} + β2yt − 1I{t > k0} + ϵt, t = 1,2, … ,T, where I{ ⋅ } denotes the indicator function. We examine two cases: case I | β1 | < 1,β2 = β2T = 1 − cT; and case II β1 = β1T = 1 − cT, | β2 | < 1, where c is a fixed constant, and {ϵt,t ≥ 1} is a sequence of i.i.d. random variables, which are in the domain of attraction of the normal law with zero means and possibly infinite variances. We derive the limiting distributions of the least squares estimators of β1 and β2 and that of the break‐point estimator for shrinking break for the aforementioned cases. Monte Carlo simulations are conducted to demonstrate the finite‐sample properties of the estimators. Our theoretical results are supported by Monte Carlo simulations.  相似文献   
10.
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