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As a form of future traffic system, connected and automated vehicles (CAVs) platoon is a typical nonlinear physical system. The CAVs can communicate with each other and exchange information. However, there is a possibility of communication failure. This failure results in the change of the platoon system status. To characterize this change, this paper proposes a dynamic topology-based car-following model and its generalized form. Then, stability analysis method is explored. Finally, taking the dynamic cooperative intelligent driver model (DC-IDM) as an example, the results of a series of numerical simulations conducted to analyze platoon stability for different communications topology scenarios are presented. The results show that communication failure leads to reduced stability, but information from more vehicles ahead and setting a larger desired time headway help to improve it. Moreover, this paper studies the critical ratio of communication failures required to ensure stability for different driving parameters.

To get better solution by improving the mutation strategy of Differential Evolution algorithm, a fractal mutation strategy is introduced. The fractal mutation factor of the proposed Fractal Mutation factor Differential Evolution (FMDE) algorithm is simulated by fractal Brownian motion with a different Hurst index. The new algorithm is test on 25 benchmark functions presented at 2005 IEEE Congress on Evolutionary Computation (CEC2005). The optimization results of at least 10 benchmark functions are significantly better than the results obtained by JADE and CoDE, and most of the rest of the test results are approximate. This shows that FMDE can significantly improve the accuracy and adaptability to solve optimization problems.

We report on the crystallographic tilting of AlN/GaN layers grown on Si (111) substrates with different miscut angles toward [110] direction. The inclination angle of the Si (111), AlN (002) and GaN (002) planes to the sample surface was measured by high resolution X-ray diffraction. We found that the tilt angles of the AlN and GaN layers with respect to the Si (111) plane are significantly larger than that predicted by the classical Nagai model. We proposed that in-plane mismatch played an important role in the tilt epitaxy of AlN/GaN layers on miscut Si (111) substrate.

Cross dock scheduling problem is a kind of highly complex optimization problem, and it is the critical issue for the efficiency of the cross docking logistics. Summarized and simplified by the practical problems, the mathematical model of cross dock scheduling problem with multi-dock doors is founded. Artificial bee colony algorithm (ABC) is presented to solve the problem. According to the characteristic of the problem and the ABC, the two-stage largest order value (LOV) based on random key encoding method is designed. To compare and analyze the performance of our proposed algorithms, 3 types with 6 scenes of instance are designed. Simulation results show that the proposed ABC algorithm is efficiency for the cross dock scheduling problem.

To investigate the protective effects of the polysaccharides isolated from ganoderma applanatum (PGA) on gastric mucosal injury in rats and the underlying mechanism.Gastric ulcer was induced by either acetic acid or pylorus ligation in the rats. The level of PGE2 and GMBF, and gastric mucus secretion were examined respectively.After oral administration of PGA (250-1000 mg x kg(-1)) repeatedly, the level of PGE2 and GMBF were obviously increased in gastric mucosa of rats as compared with the model group. The secretions of both free mucus in stomach and mucus of gastric wall were enhanced apparently by PGA in a dose-dependent manner.PGA could strengthen gastric mucosa barrier by improving the level of PGE2, GMBF and the secretion of gastric mucus, which may be one of the mechanisms underlying the protective effect of PGA on the gastric mucosa during the gastric ulcer.

To study the hypoglycemic activity of ginseng glycopeptide (GGP).Normal mice or rabbits and alloxan or streptozotocin-induced hyperglycemic rats or mice were used in the study. Blood glucose and liver glycogen levels of the experimental animals during the trial period were analyzed by spectrophotometry with O-toluidine and iodine reagents, respectively.Significant decreases in blood glucose and liver glycogen levels were induced in a dose-dependent manner after administration of GGP 50, 100, or 200 mg/kg injected ip or sc to normal mice and injected im 30 or 60 mg/kg to normal rabbits. The hypoglycemic activity of GGP lasted for about 16 h, and were examined in both normal animals and hyperglycemic animals.GGP injection induced the pronounced decreases in blood glucose and liver glycogen levels in both normal and hyperglycemic animals.

To study the hypoglycemic mechanism of ginseng glycopeptide (GGP).After administration of GGP, the levels of insulin, lactate dehydrogenase (LDH), lactic acid (LC), and oxygen consumption, as well as blood glucose (BG) and liver glycogen (LG) were measured. Based on these measurement results, the effects of GGP on insulin secretion and anaerobic/aerobic glycolysis were evaluated. Adenylate cyclase (AC) activity and cAMP level were measured to study the effects of GGP on BG and LG metabolism and to determine whether the effects were through second transmitting message system. Propranolol (beta-receptor antagonist) and phentolamine (alpha-receptor antagonist) were used to investigate whether hypoglycemic activity of GGP was through beta- or alpha-adrenoceptor. [3H]DHA (antagonist of beta-adrenoceptor) was used to determine GGP binding affinity to beta-adrenoceptor. Citrate synthetase (CTS), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), and cytochrome oxidase (CCO) activities were measured to explore GGP effects on aerobic glycolysis in liver mitochondria. Phosphorylase (PP) activity was measured to study GGP effects on liver glycogen metabolism.cAMP content and AC activity were increased when BG and LG contents in liver of mice decreased. The decrease in liver glycogen induced by GGP was inhibited by pretreatment with propranolol. Radioligand receptor assay showed that GGP was competing in vitro with [3H]DHA to bind to beta-adrenoceptor of duck erythrocyte membrane, and IC50 of GGP was 63 nmol/L. GGP inhibited LDH activity at an appropriate dosage, at which contents of BG and LG could be effectively lowered. GGP also stimulated activities of SDH, MDH, CCO, CTS, and PP.The hypoglycemic activity of GGP may be attributed to the enhancement of aerobic glycolysis through stimulation of beta-adrenoceptor and increase of various rate-limiting enzyme activities related to tricarboxylic acid cycle.

As the angle of the miscut of a Si(111) substrate increases, the luminous efficiency of InGaN LEDs decreases dramatically, along with a considerable blue shift of emission wavelength. The blue shift of the wavelength and the decrease in the efficiency are found to originate from the reduced indium incorporation and the poor uniformity of the quantum wells. The origin of the nonuniform indium incorporation of the samples is attributed to the surface morphologies formed by step bunching, as confirmed by atomic force microscopy measurements.