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The problem of optimizing the maximum range of a glide guided bomb is studied based on the principle of solving optimal control problems using the Radau pseudo-spectral method. The dynamic model of the guided bomb is nondimensionalized. Combining with the Pontryagin minimum principle, the analytic solution of the optimal control and the first-order necessary condition are derived. The trajectory optimization problem is translated to a nonlinear programming via the Radau pseudo-spectral method. Based on covector mapping principle, an optimality verification method is presented for the numerical solution. Simulation results show that the Radau pseudo-spectral method can provide a highly valuable optimal solution for engineering application. Compared with the conventional maximum lift-to-drag ratio gliding trajectory, the trajectory after optimization can be extended by more than 10%. [ABSTRACT FROM AUTHOR]

Objective Modify hydroxyapatite whisker (HAPw) by nano zinc oxide(ZnO) to synthesize a kind of antibacterial implant bone compound material, and study its degradation and substantial changing in extreme environment. Methods Nano ZnO was prepared through sol-gel method, and modified HAPw by nano ZnO to achieve nano ZnO-HAPw compound material. According to ISO 10993-14 standards,the degradation rate of nano ZnO-HAPw was tested after soaked in citrate buffer solution, the surface morphology change was examined with by scanning electric microscope(SEM) and XRD analysis. Results The degradation rate was 25.44% (HAPw/n-ZnO),18.59% (HAPw), respectively. SEMshowed apparently that HAPw fractured and the quantities of nano ZnO particles significantly reduced after soaking. XRD analysis indicated that the three strong peaks of HAPw lowered. Conclusion Nano ZnO-HAPw is a low soluble materials. [ABSTRACT FROM AUTHOR]

Objective To discuss the influence of nano-silica content which was hydrolyzed by letraethyl ortho-sioale(TEOS) on the aluminum borate whisker(AlBw) and silica filler composite resins on flexural properties. Methods The nanometer-size silicon dioxide (Si02) particles were prepared by sol-gel method based on tetraethyl orthosioate. Different proportion of AlBw and Si02 were fused and attached onto the surface of AlBw through high temperature, then polymerized with resin matrix after surface siliconization and their flexural strength and flexural modulus were determined. The effects of heat treatment to the surface morphology of AlBw and the shapes of the mixture at various proportions were characterized by TEM. Results The flexural properties of dental composite resins with AlBw-Si02 compound as inorganic fillers were significantly improved. The flexural property of a new type of dental composite resins was (130.29±8.38) MPa, when the mass ratio of AlBw and nano-Si02 particle was 3:1. Conclusion Nano-sil-ica content which was hydrolyzed by tetraethyl orthosioate improved flexural properties of the aluminum borate whisker and silica filler composite resins. [ABSTRACT FROM AUTHOR]

Objective: This study aims to assess the effects of the different thicknesses of body-shade resin layers on the color of polyetheretherketone (PEEK)-Crea.lign restorations., Methods: Five PEEK specimens with the thickness of 0.6 mm were prepared. The color values of PEEK specimens were measured. Afterward, opaque-shade resin layers (0.1 mm) and body-shade resin layers (1.5 mm) were stacked with mold. The five specimens were evenly ground to a thickness of 1.4, 1.2, 1.0, 0.8, 0.6, 0.4, 0.2, and 0.0 mm in sequence. After grinding and ultrasonic cleaning, the color value was measured., Results: With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the L*, a*, and b* values all showed downward trend with the increased thickness of the body-shade resin layer (1.0-1.4 mm). With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the color difference between the adjacent groups was less than 1.5 NBS. This difference between nonadjacent groups was more than 1.5 NBS when the thickness of the body-shade resin layer reached 0.6 mm. Color difference between PEEK-Crea.lign restoration and PEEK was more than 1.5 NBS., Conclusions: The thickness change in the body-shade resin layers influence the color of the PEEK-Crea.lign restorations. Using A2 shade Crea.lign, opaque-shade resin layer thickness is 0.1 and 0.6 mm thickness of body-shade resin layer can produce color which clinically acceptable.

Objective: To discuss the influence of nano-silica content which was hydrolyzed by tetraethyl orthosioate (TEOS) on the aluminum borate whisker (AlBw) and silica filler composite resins on flexural properties., Methods: The nanometer-size silicon dioxide (SiO2) particles were prepared by sol-gel method based on tetraethyl orthosioate. Different proportion of AlBw and SiO2 were fused and attached onto the surface of AlBw through high temperature, then polymerized with resin matrix after surface siliconization and their flexural strength and flexural modulus were determined. The effects of heat treatment to the surface morphology of AlBw and the shapes of the mixture at various proportions were characterized by TEM., Results: The flexural properties of dental composite resins with AlBw-SiO2 compound as inorganic fillers were significantly improved. The flexural property of a new type of dental composite resins was(130.29 +/- 8.38) MPa, when the mass ratio of AlBw and nano-SiO2 particle was 3:1., Conclusion: Nano-silica content which was hydrolyzed by tetraethyl orthosioate improved flexural properties of the aluminum borate whisker and silica filler composite resins.

Objective: To evaluate neurocognitive performance in first-episode schizophrenic patients and unaffected first-degree relatives of different patients samples., Methods: A total of 42 patients with first-episode schizophrenia, 24 unaffected first-degree relatives and 40 healthy individuals, matched with age, gender and years of education, were recruited from both outpatients and inpatients after being diagnosed with structured tool (SCID-I/P). Subjects' cognitive performance was evaluated by a set of neuropsychological test battery, which assessed four cognitive domains including learning and memory, motor skills, speed of processing and executive function., Results: Healthy individuals performed better than first-episode schizophrenic patients in nearly all cognitive domains (ES=0.63-1.54) with exception of inhibition sub-domain. first-degree relatives showed moderate impairment in verbal learning (ES=0.62), digital symbol (ES=1.05), symbol search (ES=1.18), animal category (ES=0.80) and WCST perseverate errors (ES=0.68). Degree of impairment in first-degree relatives was less than that in the patients., Conclusion: Patients with first-episode schizophrenia have global neurocognitive deficits. Independent first-degree relatives also have deficits in some neurocognitive domains, with a moderate degree between patients and normal controls. Our results indicate that neurocognitive performance may be viewed as a biomarker for candidates reflecting genetic liability for schizophrenia.