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Learning from the motion principle of quadrotor, a symmetric propeller AUV, which has small size and low velocity is designed. Compared with the AUV equipped with rudders, it has better maneuverability and manipulation at low velocity. According to the Newton-Euler method, the 6 DOF kinematic model and dynamic model of the propeller AUV are established. A stability controller that consists of 3 different PID controllers is designed. It makes the depth and attitude angle as trigger conditions, and the relevant controller is chosen in different moving process. The simulation experiments simulate ideal motion state and disturbed motion state, and experiments results show that the stability controller based on combined sections method can make the best of mature technology of PID, and meet the control requirements in different stages. It has a higher respond speed and accuracy, improving the stability of the propeller AUV under the disturbance of complex ocean currents.

Low-cycle fatigue tests were conducted on the directionally solidified nickel-base super- alloy DZ125 at 850°C in the unexposed and exposed specimens for 2, 15, 25 and 50h in hot corrosion environment. The pre-exposed specimen exhibited a lower life than unex- posed specimens. Fatigue cracks in the unexposed specimens are initiated from defects near the surface, while the cracks of exposed specimens preferentially occur on the sur- face. Hot corrosion damage in fatigue life was found to be associated with the reduction of the bearing area. A novel life prediction methodology based on continuum damage mechanics was proposed to predict the experimentally observed decrease in low-cycle fa- tigue life with increasing prior exposure time.

A novel in situ-foaming material was successfully prepared by a naphthalene-based hydroxyl-containing poly(arylene ether ketone) (PAEK) modified with thermally labile tert-butyloxycarbonyl which can decompose and in situ generate CO2 and isobutene as the foaming agents. The structure and thermal properties of the polymers were characterized by using 1H NMR spectra and thermogravimetry coupled time-resolved mass spectrogram (TG/MS). The resulting polymers exhibited relatively high Tg because of the existence of a rigid naphthalene moiety. Then closed microcellular porous membranes with a wide range of expansion ratio (ER) were obtained by a simple thermal treatment from 140 °C to 280 °C for 60 seconds, without using any other physical or chemical foaming agents. The highest ER was 53.98%. This method has never been reported before on high-performance poly(aryl ether) materials. Furthermore, we investigated the relationship between the foaming temperature and the morphology of membranes in detail by using density measurement and scanning electron microscopy (SEM).

A series of sulfonated naphthalene-based poly (arylene ether ketone)s (SNPAEK-xx) with pendant sulfoalkyl groups were prepared by polycondensation of 1,5-bis(4-fluorobenzoyl)-2,6-dimethoxynaphthalene and o-methylhydroquinone, followed by a demethylation and sulfobutylation reaction. The sulfonate degree of SNPAEK-xx could be controlled easily by adjusting the ratio of 1,4-butane sultone to the hydroxyl content in the demethylated polymers. Flexible and tough membranes with reasonably high mechanical strength were prepared. SNPAEK-xx membranes showed a high ionic exchange capacity (IEC) in the range of 1.13 to 2.27 mequiv. g−1, and the highest proton conductivity of 0.191 S cm−1 at 80 °C. They exhibited low methanol permeability in the range of 1.25–10.22 × 10−7 cm2 s−1, which was much lower than that of Nafion 117. Transmission electron microscopy analysis of SNPAEK-xx revealed that they had a more obvious phase separated structure between the hydrophilic side chain and hydrophobic fully aromatic domains at a higher IEC. Combining their high thermal and mechanical stability, high selectivity, lower water swelling ratio, SNPAEK-xx membranes could be promising materials as alternative to Nafion membranes for direct methanol fuel cell applications.

The problem of data representation on a sphere of unknown radius arises from various disciplines such as Statistics (spatial data representation), Psychology (constrained multidimensional scaling), and Computer Science (machine learning and pattern recognition). The best representation often needs to minimize a distance function of the data on a sphere as well as to satisfy some Euclidean distance constraints. It is those spherical and Euclidean distance constraints that present an enormous challenge to the existing algorithms. In this paper, we reformulate the problem as an Euclidean distance matrix optimization problem with a low rank constraint. We then propose an iterative algorithm that uses a quadratically convergent Newton-CG method at its each step. We study fundamental issues including constraint nondegeneracy and the nonsingularity of generalized Jacobian that ensure the quadratic convergence of the Newton method. We use some classic examples from the spherical multidimensional scaling to demonstrate the flexibility of the algorithm in incorporating various constraints. We also present an interesting application to the circle fitting problem

A new bisphenol monomer, 3,3′,5,5′-tetramethoxy-4,4′-dihydroxybiphenyl, was synthesized and copolymerized to prepare diphenyl-based poly(arylene ether sulfone) copolymers containing tetra-methoxy groups (MOPAES). After converting the methoxy group to the reactive hydroxyl group, the resulting side-chain-type sulfonated copolymers (SOPAES) with a hydrogen bonded network were obtained by a sulfobutylation reaction. The copolymers were characterized and confirmed by 1H NMR, FT-IR, thermogravimetric analysis (TGA) and small-angle X-ray scattering. The water uptake, proton and methanol transport properties of the resulting membranes were also determined for fuel cell applications. These SOPAES series membranes showed high proton conductivity in the range of 0.032–0.054 and 0.084–0.142 S cm−1 at 25 and 80 °C under hydrated conditions, respectively. SOPAES-40 (IEC = 1.38 mequiv. g−1) showed comparable proton conductivity with Nafion 117 in the hydrated state. The methanol permeability of these membranes was in the range of 1.58–4.29 × 10−7 cm2 s−1, which is much lower than Nafion (1.55 × 10−6 cm2 s−1). It should be noted that the intra/inter hydrogen bonds formed between sulfonic acid and hydroxyl groups or between hydroxyl and hydroxyl groups improved the mechanical properties and reduced the methanol permeability of the membranes effectively. A combination of suitable proton conductivity, low water uptake, and low methanol crossover for selected SOPAES indicates that they are good candidates as proton exchange membrane materials for fuel cells.

A series of cross-linked sulfonated poly (arylene ether ketones) containing tri-side-chain pendent sulfonic groups (SQNPAEK) were prepared by the Friedel–Crafts acylation reaction in order to solve the problem of high methanol crossover and maintain high proton conductivity for direct methanol fuel cells. For this purpose, sulfonated poly(arylene ether ketones) with pendent carboxylic acid groups were synthesized based on phenolphthalein carboxylic monomers to be used as a macro-crosslinker. The cross-linked membranes showed improved mechanical properties, chemical resistance and oxidative stability. The water uptake and swelling ratio of cross-linked membranes decreased from 57.3% to 18.7%, and from 12.2% to 3.03%, respectively. And the methanol permeability decreased from 0.94 × 10−7 cm2 s−1 to 0.37 × 10−7 cm2 s−1. Regarding the high proton conductivity, it showed enhanced performance over the pristine membrane, up to 0.29 S cm−1. Thus, the cross-linked membranes possessed the better performance implying their potential for practical application in high-energy-density devices.

The water-air UAV is a new kind of aircraft which cruises in the air on ordinary occasions. Specially, it can submerge for a short distance underwater and take off again when necessary. It has lots of superior performance and wide application fields for both military and civil users. Over the last decades, several vehicles like it have been developed for special uses. First, the research necessity and development history of water-air UAV and other similar vehicle are reviewed in this paper. Then, the involved key technologies and their application status, such as configuration, power, control and communication are introduced. It is certain that the water-air UAV will play an important role in the world ahead.

To analyze the air flow interference between upper and lower wings in axial ring wing configuration, NASA SC(2)-1006 supercritical airfoil is chosen as the basic airfoil. Flow field around the double-wing structure with different relative distances between upper and lower wings is numerically simulated, using SST turbulence model, and the numerical conclusion about the influence of relative distance D/L on the aerodynamic performance is drawn. It is shown that, at the speed Ma = 0.8, reflection of shockwave between the upper wing and the lower wing has a great negative effect on both lift and drag coefficient. When D/L = 0.1, and the angle of attack AOA = 0°, the resultant lift produced by the two wings is equivalent to that of the single wing, while the resultant drag is 4 times of that of the single wing, which shows a poor aerodynamic characteristic. With the increasing of the relative distance, the intensity of the shockwave between the upper and lower wings is weakened and the negative effect is relieved. Furthermore, the growth of the angle of attack AOA can obscure the negative effect. It could provide helpful reference to the design of axial ring wing aircraft.

Novel self-crosslinked alkaline electrolyte membranes with high hydroxide ion conductivity, excellent dimensional stability and extraordinary solvent resistance stability are synthesized successfully without using any catalyst or separate crosslinker. Monitored by 1 H NMR analysis, the synthetic process of trimethyl poly (ether sulfone)-methylene quaternary ammonium hydroxide (TPQAOH) is found to be simple and efficient. The chemical and thermal stability of the synthetic SCL-TPQAOH-x membranes are better than other anion exchange membranes. At the same time, the hydroxide ion conductivity of SCL-TPQAOH-0.67 membrane reaches 33 mS cm −1 with an IEC value of 1.07 mmol g −1 at 80 °C, which complies with the requirements of alkaline fuel cells. This investigation also proves that self-crosslinking technology is a very simple and effective approach in improving the performance of alkaline electrolyte membranes.

To explore the association between Insertion/Deletion polymorphism of the angiotensin converting enzyme (ACE) gene and the effects of Living High-Exercise High-Training Low (HiHiLo) on muscle oxygenation (MO), Seventy-one healthy men of Han nationality in northern China underwent HiHiLo training for 4 weeks. Training programme was as follows: exposure in hypoxic environment (14.5%~14.8%O2, 10h/day), three times hypoxic training per week (15.4%O2), and training at sea level. Resting MO, exercising MO and resuming MO were measured by non-invasive near infrared spectroscopy (NIRS) before and after the protocol, and the ACE gene I/D polymorphism was detected by PCR. The findings indicated that exercising MO and resuming MO all increased markedly after training (P< 0.05), but resting MO declined. As to genotypes, no significant differences were in the baseline MO among groups before HiHiLo. Increase in resting MO and exercising MO in II and ID groups were more than those in DD groups, but decline in resuming MO in II and ID groups was less than those in DD groups.The present study suggested that HiHiLo could be helpful for developing individual resting MO and exercising MO, but harmful for resuming MO. Moreover, MO of men carrying II and ID probably were more sensitive to the hypoxic training than those carrying DD.

Turbine vanes and blades are the most intensively loaded elements in that they are subjected to a large variety of mechanical and high temperature loads. The thermal barrier coatings (TBCs) are widely used on different hot components of gas turbines, as blades and vanes, for both, power engineering as well as aeronautical applications. Currently, two methods are used for depositing TBCs on substrate, which are plasma spray (PS) and electron beam-physical vapor deposition (EB-PVD). A typical TBCs system consists of two thin coatings, including a ceramic coating and a metallic bond coat. Despite considerable efforts, the highly desirable prediction of their life time is still a demanding task. The PS coating was focused on in this work. Firstly, the TBCs systems are multiplayer material systems. The material properties are not easily determined, such as Young’s modulus of the top-coating of TBCs. Using the resonant frequency and the composite beam theory, the Young’s modulus of APS TBCs was gotten under from room temperature to 1150°C. Then using a commercial finite-element program, the model geometry is that of a cylinder specimen. The interface region between bond coat and top coating is modeled and meshed with a sinusoidal geometry. The temperature was designed and cycled over a range from room temperature to 1050°C. The force-air-cooling was designed to form temperature gradient across the thickness of TBCs. Finally, the fatigue life of TBCs was predicated. The maximum relative error is 20.1%.

Tensile creep tests were conducted at 980°C under a constant stress on a single crystal nickel base superalloy. Some tests were interrupted at different stages during the creep process. The strain-time curves indicated that this alloy exhibited conventional primary, steady-state and tertiary stages at this temperature. The transmission electron microscope (TEM) observations of foils taken from the gauge sections of specimens were made to interpret the microstructural evolution that occurred during the creep process. It was found that the γ′ particles were rafted in the direction perpendicular to the applied stress. The acceleration of the creep rate was related to the change of the dislocation density.

We have developed basic ionic liquid-based hybrid membranes with ionic liquid modified zeolitic imidazolate frameworks (ZIFs) as fillers, aiming to enhance the electrochemical and physical properties of the membrane.

The hydrodynamic model of a vehicle exiting the water surface obliquely has been analyzed. The analyzed object is a cylinder vehicle and its motion characteristics. Two methods have been used to simulate the water-exit process under the same conditions: Numerical Simulation Method (NSM) and Theoretical Model Solution Method (TMSM). The comparison results of the two methods can validate the hydrodynamic model founded in this paper. Different initial angles and different initial velocities have been simulated by this hydrodynamic model and the numerical simulation has been analyzed. The analysis reveals the rule of change of altitude and position of the vehicle in the water-exit process, and its motion after it exits the water surface. This paper explains why it is more difficult for the vehicle to exit the water obliquely than vertically. The results show that the hydrodynamic model of the water exiting vehicle can be used to research the exiting water motion characteristics. The models simulate the physics of motion realistically and this hydrodynamic model can be used as a foundation for the future research of the stability and control of a vehicle exiting the water.

An additional isotropic internal variable is utilized to extend the Bodner Partom unified viscoplastic constitutive model(original B-P) to improve the modeling of rate dependent plasticity and cyclic hardening behaviors of metals. The extended model (new B-P) contains two isotropic internal variables: one plays the role of representing the fast hardening in smaller inelastic strain range, while the other evolutes at slower speed accompanied by larger accumulated inelastic deformation, such as cyclic hardening. To examine the validity of the extended constitutive model, the rate dependent plasticity of a Ni-base superalloy Udimet 720Li at 650°C and 700°C are characterized using both models. Not only numerical simulations are conducted for various loading conditions by implementing both models into ABAQUS using a user material subroutine, also a systematic comparison between two models is completed. Numerical results show that the extended material constants in the new model provide more flexible capability in modeling the inelastic behavior of the material with sound accuracy.

To solve the hardware/software(HW/SW) partitioning problem on the system that contains only one CPU, a new algorithm based on GA is studied. Firstly, the concept of hardware orientation is put forward, and then used to create the initial colony of GA and in mutation process, which reduces the randomicity of initial colony and the blindness of search. Secondly in the process of GA, crossover and mutation probability become more and more small, this not only ensures a big search space in the early, but also keeps the good solution later. Experimental statistics show that the efficiency of the proposed algorithm outperforms the algorithms in comparison by up to 23% in large-scale problem. What’s more, it can obtain better solution. In conclusion, the proposed algorithm has higher efficiency and appears to be a better solution under specific conditions.

Based on Qi, Sun, and Zhou's smoothing Newton method, we propose a regularized smoothing Newton method for the box constrained variational inequality problem with P0-function (P0 BVI). The proposed algorithm generates an infinite sequence such that the value of the merit function converges to zero. If P0 BVI has a nonempty bounded solution set, the iteration sequence must be bounded. This result implies that there exists at least one accumulation point. Under CD-regularity, we prove that the proposed algorithm has a superlinear (quadratic) convergence rate without requiring strict complementarity conditions. The main feature of our global convergence results is that we do not assume a priori the existence of an accumulation point. This assumption is used widely in the literature due to the possible unboundedness of level sets of various adopted merit functions. Preliminary numerical results are also reported.

Purposes To explore the association between Insertion/Deletion polymorphism of the angiotensin converting enzyme (ACE) gene and the effects of Living High-Exercise High-Training Low (HiHiLo) on arterial oxygen saturation (SPO2), so that sports practitioners comprehend better individual hypoxia training effects, coach can constitute individual training program. Procedures and Methods 71 healthy men of Han nationality in northern China underwent HiHiLo training for 4 weeks Training programme was as follows: exposure in hypoxic environment (14.5–14.8 % O2, 10 h/day), three times hypoxic training per week (15.4 % O2), and training at sea level. Resting, exercising and resuming SPO2 were measured before and after the protocol, and the ACE gene I/D polymorphism was detected by PCR. Results There was no significant differences were in the baseline SPO2 among groups before HiHiLo. Exercising and resuming SPO2 both increased significantly in total and II, ID after training than those before the training (P 0.05). Conclusions HiHiLo could be helpful for developing individual exercising and resuming SPO2. Moreover, SPO2 of men carrying 2 and ID probably were more sensitive to the hypoxic training than those carrying DD.

To explore the association between Insertion/Deletion polymorphism of the angiotensin converting enzyme(ACE) gene and the effects of HiHiLo (living at high altitude-exercise at high altitude-training at low altitude) training, Seventy-one healthy men of Han nationality in northern China underwent HiHiLo training for 4 weeks. Training programme was as follows: exposure in hypoxic environment (14.5%∼14.8%O 2 , 10h/day), three times hypoxic training per week (15.4%O 2 ), and training at sea level. VO 2 max and Haemogram were measured before and after the protocol, and the ACE gene I/D polymorphism was detected by PCR. The findings indicated that the frequency of genotypes in the subjects was in Hardy-Weinberg equilibrium. No significant differences were in the baseline VO 2 max, VO 2 max/w, RBC, HB and HCT among groups. VO 2 max, VO 2 max/w, RBC, HB and HCT all increased more significantly in total and II, ID after training than those before the training (P < 0.01), but no significant changes showed in DD (P > 0.05) except HCT. The present study suggested that HiHiLo training could be helpful for developing aerobic ability. Moreover, men carrying II and ID probably were more sensitive to the hypoxic training than those carrying DD.

In the title coordination polymer, [Zn(C14H11NO3)(C2H6OS)]n, each ZnII ion is five-coordinated in a slightly distorted trigonal–bipyramidal coordination environment, formed by three O atoms from two 2-[(2-oxido-1-naphthyl)methyleneamino]propanoate ligands, one O atom from a dimethyl sulfoxide molecule and the N atom from the aminopropanoate ligand. The propanoate ligands bridge ZnII ions, forming a zigzag chain parallel to [010].

In the title coordination polymer, [Zn(C(14)H(11)NO(3))(C(2)H(6)OS)](n), each Zn(II) ion is five-coordinated in a slightly distorted trigonal-bipyramidal coordination environment, formed by three O atoms from two 2-[(2-oxido-1-naphth-yl)-methyl-eneamino]propanoate ligands, one O atom from a dimethyl sulfoxide mol-ecule and the N atom from the amino-propanoate ligand. The propanoate ligands bridge Zn(II) ions, forming a zigzag chain parallel to [010].

To explore the distribution about genotype and allele frequencies of Nco I polymorphism in the CKMM gene in Han population in Northern China, and investigate what the genotypes were, PCR-RFLP was used to examine the genotype and allele frequencies of 306 unrelated healthy persons. Sequencing was used to analyze all three genotypes. Chi2 test was used to compare the frequencies between Chinese Han population and foreign population. The Nco I polymorphism was A/G. The allele frequencies were as follows: A=86%,G=14% . The genotype frequencies were A/A=74%, A/G=24%, G/G=2% and they were in Hardy-Weinberg equilibrium. The site of Nco I in the CKMM from Chinese Han population had polymorphism. No significant difference was detected in genotype and allele frequencies between men and women. There were significant differences between Chinese Han population and those in Europe and America, but no significant difference was detected between Chinese population and Korean population.

In this paper, we obtain new sufficient conditions ensuring existence, uniqueness, and global asymptotic stability (GAS) of the equilibrium point for a general class of delayed neural networks (DNNs) via nonsmooth analysis, which makes full use of the Lipschitz property of functions defining DNNs. Based on this new tool of nonsmooth analysis, we first obtain a couple of general results concerning the existence and uniqueness of the equilibrium point. Then those results are applied to show that existence assumptions on the equilibrium point in some existing sufficient conditions ensuring GAS are actually unnecessary; and some strong assumptions such as the boundedness of activation functions in some other existing sufficient conditions can be actually dropped. Finally, we derive some new sufficient conditions which are easy to check. Comparison with some related existing results is conducted and advantages are illustrated with examples. Throughout our paper, spectral properties of the matrix (A + Atau) play an important role, which is a distinguished feature from previous studies. Here, A and Atau are, respectively, the feedback and the delayed feedback matrix defining the neural network under consideration.

The alphavbeta3 integrin has been shown to promote cell migration through activation of intracellular signaling pathways. We describe here a novel pathway that modulates cell migration and that is activated by alphavbeta3 and, as downstream effector, by cdc2 (cdk1). We report that alphavbeta3 expression in LNCaP (beta3-LNCaP) prostate cancer cells causes increased cdc2 mRNA levels as evaluated by gene expression analysis, and increased cdc2 protein and kinase activity levels. We provide three lines of evidence that increased levels of cdc2 contribute to a motile phenotype on integrin ligands in different cell types. First, increased levels of cdc2 correlate with more motile phenotypes of cancer cells. Second, ectopic expression of cdc2 increases cell migration, whereas expression of dominant-negative cdc2 inhibits migration. Third, cdc2 inhibitors reduce cell migration without affecting cell adhesion. We also show that cdc2 increases cell migration via specific association with cyclin B2, and we unravel a novel pathway of cell motility that involves, downstream of cdc2, caldesmon. cdc2 and caldesmon are shown here to localize in membrane ruffles in motile cells. These results show that cdc2 is a downstream effector of the alphavbeta3 integrin, and that it promotes cell migration.

The beta(1C) integrin is an alternatively spliced variant of the beta(1) subunit that contains a unique 48-amino-acid sequence in its cytoplasmic domain. We have shown previously that beta(1C) is a potent inhibitor of cell proliferation and that in vivo its expression is downregulated in prostate and breast carcinoma. In this study, we describe a panel of specific monoclonal antibodies that react with the beta(1C) cytodomain. We show by immunoblot analysis that the newly generated monoclonal antibodies specifically recognize the beta(1C) cytodomain expressed as glutathione S-transferase fusion protein. The specificity of the antibodies to beta(1C) was confirmed in competition studies by immunoblotting using beta(1C)-specific synthetic peptides. These monoclonal antibodies reacted, in enzyme-linked immunosorbent assays, with the beta(1C) 785-808 peptide but failed to bind the beta(1C) 778-794, beta(1C) 805-825, or beta(1A) 765-798 peptides. Thus, the epitope recognized by the antibodies is located within the Q(795)-F(804) beta(1C) cytoplasmic sequence; this region overlaps the previously described Q(795)-Q(802) domain necessary for beta(1C) to inhibit cell proliferation. To our knowledge, these are the first monoclonal antibodies specific for a beta(1) cytoplasmic isoform. The monoclonal antibodies described here will be useful tools for dissecting functional differences, among beta(1) integrin variants, as well as for the study of the role of beta(1C) in prostate and breast epithelial cell proliferation.

Integrins are a large family of transmembrane receptors that, in addition to mediating cell adhesion, modulate cell proliferation. The beta1C integrin is an alternatively spliced variant of the beta1 subfamily that contains a unique 48-amino acid sequence in its cytoplasmic domain. We have shown previously that in vitro beta1C inhibits cell proliferation and that in vivo beta1C is expressed in nonproliferative, differentiated epithelium and is selectively downregulated in prostatic adenocarcinoma. Here we show, by immunohistochemistry and immunoblotting analysis, that beta1C is coexpressed in human prostate epithelial cells with the cell-cycle inhibitor p27(kip1), the loss of which correlates with poor prognosis in prostate cancer. In the 37 specimens analyzed, beta1C and p27(kip1) are concurrently expressed in 93% of benign and 84%-91% of tumor prostate cells. Forced expression of beta1C in vitro is accompanied by an increase in p27(kip1) levels, by inhibition of cyclin A-dependent kinase activity, and by increased association of p27(kip1) with cyclin A. beta1C inhibitory effect on cell proliferation is completely prevented by p27(kip1) antisense, but not mismatch oligonucleotides. beta1C expression does not affect either cyclin A or E levels, or cyclin E-associated kinase activity, nor the mitogen-activated protein (MAP) kinase pathway. These findings show a unique mechanism of cell growth inhibition by integrins and point to beta1C as an upstream regulator of p27(kip1) expression and, therefore, a potential target for tumor suppression in prostate cancer.