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The large-span pipe bridge is widely applied to long-distance water diversion projects because of its large crossing capacity, strong integrity, and adaptability to complex terrain. However, under the action of an earthquake, the pipe bridge will often produce large displacement, which can lead to large deformation of the whole system and damage to the pipe bridge structure. At present, there are relatively few studies on the seismic response of such pipe bridges for water diversion, and even there is also a lack of special design specifications for pipe bridges. Combined with the construction practice of the KLH long-span pipe bridge, based on the finite element analysis, the seismic response characteristics and dynamic stabilization of the long-span pipe bridge are analyzed, so the structure optimization scheme is proposed for the key parts of the bridge. The research results can provide new ideas for the seismic design of the long-span pipe bridge.

In this paper, a new lightning electric field (LEF) signals denoising approach combined with empirical mode decomposition (EMD) and wavelet transform (WT) is proposed. Unlike the conventional EMD or WT denoising approaches, we use EMD to decompose the LEF signal firstly, the continuous mean square error(CMSE) criteria are used to determine a turning point in the original signal energy, then the Birge-Massart threshold wavelet denoising method is employed to denoise the high frequency component which contains lots of noise. Finally, the clean high frequency component and the remaining low frequency intrinsic mode function, and the residual of the EMD operation are employed to synthesize a cleaner LEF signal. The method is illustrated on real data, and the performance of the proposed method is evaluated in terms of several standard metrics. The results show that the proposed method is able to reduce noise from the noisy LEF signals more accurately and effectively in comparison to EMD filtering and Wavelet filtering methods.

In this paper, a novel method for face recognition, called two-dimensional weighted and locality preserved discriminant analysis (2D-WLPDA) is proposed. The new algorithm is developed based on three techniques: (1) locality preserved embedding, by embedding nearest-neighbor graphs which characterize the within-class compactness of the same class samples, 2D-WLPDA discovers the submanifold of images space; (2) image based projection which can avoids the small sample problem and improves the computation efficiency;(3) weighting contributions of individual class pairs which alleviates the overlap of neighboring classes in Fisher criterion for a k-class problem with k>2. We experimentally compare 2D-WLPDA to other feature extraction methods, such as 2D-LDA, 2D-PCA and 2D-DLPP, 2D-WLPDA has better recognition performance.

Concrete plate is mainly anti-seepage structure for rockfill dam and essential to avoid dam destruction. Cooling shrinkage will be effectively compensated by mix MgO, as a result, it have been widely used in hydraulic structure. However, with large radiating surface, uniform heat exchange and small bottom restriction, stress characteristic of concrete plates is much different from conventional massive concrete structure. Therefore, impact of MgO on stress characteristic of concrete plates is unclear. In view of this, construction process using MgO concrete and ordinary concrete are simulated based on practical project data. Conclusions indicate that tensile stress of concrete plates in cooling stage can be reduced by adding MgO.

The δ-ferrite to γ-austenite phase transformation process of low carbon steel was observed in-situ under a confocal scanning laser microscope and the influence of manganese and chromium on the migration of δ/γ interphase boundary during the δ to γ phase transformation was studied. It was found that the δ/γ interphase boundary becomes unstable with the decrease of temperature, from planar to curved morphology during the δ to γ phase transformation of Fe-0.08C steel and Fe-0.08C-0.8Mn steel. But in Fe-0.08C-0.8Cr steel, the δ/γ interphase boundaries are stable with planar morphology during the whole δ-ferrite to γ-austenite transformation. The destabilization of δ/γ interphase boundary in Fe-0.08C and Fe-0.08C-0.8Mn steels results from high degree of supercooling and sub-boundaries in γ, respectively. The stabilization of δ/γ interphase boundary in Fe-0.08C-0.8Cr steel results from the slow diffusion rate of carbon atom induced by the addition of chromium.

Binocular stereo vision ranging method taking contour boundary center of measurement object as matching features was investigated. And experimental platform for binocular stereo vision ranging system was built up. The stereo vision ranging system comprised four modules: camera calibration, stereo calibration, stereo rectification and features extraction. Firstly, the intrinsic parameters of single camera were obtained by camera calibration and relative pose of two cameras was obtained by stereo calibration. Then the left and right images were rectified into a frontal parallel arrangement by Bouguet’s method. The edge pixels of contours were detected by image processing. Then the disparity and the distance was calculated taking contour center as matching features. Finally, measurement error analysis was performed to verify the proposed method with good practicability.

Based on transient heat transfer theory and finite element method, a 3D finite element model was created to simulate the heat transfer of the vertical U type berried pipe of the ground source heat pump system. At the same time, the pipe algorithm applied successfully in the numerical simulation of concrete temperature field was introduced. The corresponding program was written. Taking the true experiment conditions as the input data and boundary condition of the computation model, the 3D dynamic simulation of the heat transfer between the berried pipe and sandy soil was carried out. The calculated temperatures of the output water of the pipe and the measure points in soil at different times met the experiment results very well, which verified the effectiveness and the reliability of the algorithm and the model. Beneficial exploration is made for providing more detailed and accurate data for the designer.

For virtue of small volume and fast speed of construction, arch dam is the most suitable dam type in cold region, where construction period is relatively short each year. Low average value and large amplitude of atmospheric temperature make temperature stress distribution of arch affect directly by thickness of permanent insulation material as while as the time of thermal insulation. Extreme climate lead to stricter external insulation requirement for cold region arch than these in common district, however, thermal insulation will increase the burden of artificial cooling and extend the construction period. Therefore, it is complicated and critical for arch dam crack prevention to study on permanent thermal insulation. In view of this, finite element method was applied for simulation of construction processes of a practical project in cold region. Influence of permanent thermal insulation layer thickness and selection of insulation time is analyzed, in order to provide basis for permanent thermal insulation optimization.

Some cracks are observed in a heightening project of a concrete gravity. In order to investigate and solve this problem, the three-dimensional finite element simulation and nonlinear cracking analysis are implemented in this paper to analyze the causes of cracks and their propagation trends. This work is helpful to design the proper crack controlling plans. The research shows that large tensile stress has accumulated during construction, especially after an early air temperature sudden drop in November, the tensile stress increases 3MPa in general on the concrete surface, which exceeds the tensile strength of concrete and causes cracking. Therefore, the crack is the result of both the accumulated temperature stress during construction and temperature sudden drop. The crack will further propagate during another temperature sudden drop, but extended range is limited. If concrete tensile strength is greater than 2.5MPa, the cracks will not penetrate throughout the dam body along the water flow direction.

Under the action of annual change and sudden drop of air temperature, thermal induced cracking will occur in concrete dam during the operation period. For exploring the temperature control measures for crack prevention, taking a concrete gravity dam section as the research object, sensitivity analyses to the factors which affecting the water-cooling effect are conducted with 3D FEM, some significant suggestions for the water cooling are presented. The results show that, the stresses of the dam surface will decrease to a certain extent after water cooling in the operation period using the cooling water pipe which embedded during construction period, and the cracking risk of the dam will reduce. The study provides a new train of thought for the temperature control and crack prevention of the mass concrete during the operation period.

Maximum Scatter Difference (MSD) aims to preserve discriminant information of sample space, but it fails to find the essential structure of the samples with nonlinear distribution. To overcome this problem, an efficient feature extraction method named as Locality Preserving Maximum Scatter Difference (LPMSD) projection is proposed in this paper. The new algorithm is developed based on locality preserved embedding and MSD criterion. Thus, the proposed LPMSD not only preserves discriminant information of sample space but also captures the intrinsic submanifold of sample space. Experimental results on ORL, Yale and CAS-PEAL face database indicate that the LPMSD method outperforms the MSD, MMSD and LDA methods under various experimental conditions.

The heat-exchange efficiency between buried pipes of the ground coupled heat pump and the surrounding soil is influenced by many factors. To design the Heat Pump better, a three-dimensional FEM method which contains buried pipes and considers changing water temperature along the pipe is applied to simulate the heat exchange progress between buried pipes and the surrounding soil. In this paper, the influence of the inlet water temperature, the flow, operating modes and the distance between branches on the heat-exchange efficiency are analyzed and the reasonable suggestions is proposed to benefit the design and operation of the Ground coupled heat pump.

Gate pier may cause damaged by construction joints under inappropriate pouring in Pengshui Hydropower Station. Based on nonlinear FEM, a contact algorithm is adopted to simulate interaction of construction joints between the overflow dam surface and gate pier. With different contact type and loading, the deformation and stress are analyzed comparatively in detail in order to evaluate the strength and safety of the gate pier. The results show that existence of construction joints reduces the stiffness of the structure, but satisfies the requirements of original reinforcement project, which have a little effect on safety of the gate pier.

The spiral case with combinatorial embedding manner is a novel design and inherits the advantage of the general types of embedding manners of embedded with cushion layers and embedded directly, which is progressively used in hydro projects. In the present paper, the mechanical behavior of a larger spiral case with combinatorial embedding manner is analyzed by using 3-D non-linear finite element method. The deformation of the spiral case structure and crack analysis of outer reinforced concrete structure are carried out. The strengthening measures under the engineering control criterion are also discussed. The results show that the penetrating crack will appear in the concrete and the relative rising displacement of generator pedestal structure is out of the control criterion if no strengthening measures implemented. Increasing the quantity of reinforcement only is not able to hold back the penetrating cracks. The enhancement of the tensile strength of concrete is an effective way to decrease the range of crack propagation, resist the penetrating and decrease the rising displacement of generator pedestal structure. It also indicated that extending the laying length of cushion is another effective way to decrease the rising displacement of generator pedestal structure

Based on Numerical Manifold Method (NMM), a novel method is presented for computing Stress Intensity Factor (SIF) of cracks. The Williams expansions are employed as the analytical solutions in the mesh containing the crack tip. And high-order polynomial functions are used as the numerical solutions in the surrounding meshes. Then the SIFs are computed via combination of the numerical solutions and the analytical solutions. Meanwhile, the meshes in NMM need not conform to the physical boundaries including the crack edges, allowing the cracks arbitrarily align within the meshes. The given example shows the validity of the method.

Adrenomedullin (ADM) has the vasodilatory properties and involves in the pathogenesis of vascular calcification. ADM could be degraded into more than six fragments in the body, including ADM(27-52), and we suppose the degrading fragments from ADM do the same bioactivities as derived peptides from pro-adrenomedullin. The present study carries forward by assessing the effects on vascular calcification of the systemic administration of ADM(27-52). The rat vascular calcific model was replicated with vitamin D3 and nicotine. ADM or/and ADM(27-52) were systemically administrated with mini-osmotic pump beginning at seventh day after the model replication for 25 days. Vascular calcific nodules histomorphometry, vascular calcium content, vascular calcium uptake, alkaline phosphatase activity, and osteopontin-mRNA quantification in aorta were assessed. ADM limited 40.2% vascular calcific nodules (P0.01), did not effect on calcium content (P0.05), reduced 44.4% calcium uptake (P0.01), lowered 21.1% alkaline phosphatase activity (P0.01), and regulated 40.9% downwards osteopontin-mRNA expression (P0.01) in the aorta of rats with vascular calcification. ADM(27-52) receded 32.0% vascular calcific nodules (P0.01), taken from 55.5% calcium content (P0.01), did not affect calcium uptake (P0.05), inhibited 22.5% alkaline phosphatase activity (P0.01), and restrained 21.9% osteopontin-mRNA expression (P0.01) in the aorta of rats with vascular calcification. Both of ADM and ADM(27-52) did interact on vascular calcification each other. ADM could partially antagonize the effects of ADM(27-52) in taking from calcium content (17.5%, P0.01) and in receding vascular calcific nodules (18.6%, P0.01). ADM could obviously enhance the action of ADM(27-52) in inhibiting alkaline phosphatase activity (14.4%, P0.01) and in reducing calcium uptake (11.4%, P0.01). ADM(27-52) could partially antagonize the effects of ADM on regulating downwards osteopontin-mRNA expression (17.0%, P0.01). It is concluded that ADM(27-52) derived from ADM acts as an inhibitory agent on vascular calcification, with special mechanisms different from ADM derived from ADM progenitor molecule.

Objective Aldosterone is involved in cardiovascular diseases such as hypertension and heart failure by inducing sodium retention and vascular remodeling, which is characterized by fibroblast proliferation and migration in adventitia. It is well known that aldosterone stimulates vascular smooth muscle cells and fibroblasts to produce and secrete adrenomedullin (ADM), a multiple functional peptide with an important cytoprotective effect against cardiovascular damage. We examined the effect of aldosterone on ADM production and secretion and its mRNA expression in rat aortic adventitia to study the paracrine/autocrine interaction between endogenous ADM and aldosterone. Methods ADM produced and secreted from adventitia stimulated by aldosterone in the absence or presence of spironolactone, RU486 or spironolactone together with RU486 were detected by radioimmunoassay, proliferation in adventitia cells was evaluated by the level of [ 3 H]-thymine incorporation, and preproADM gene expression was measured by semi-quantitative reverse transcriptase polymerase chain reaction. Results Adventitial ADM secretion and mRNA expression stimulated by aldosterone were concentration-dependent as was the inhibitive effect of ADM on aldosterone-induced proliferation. The induction of aldosterone in ADM secretion was mediated by mineralocorticoid receptor. Antagonists of specific receptors of calcitonin gene-related peptide (CGRP) receptor type 1 and ADM both potentiated the proliferation effect-induced by aldosterone; and thiorphan, an inhibitor of the enzyme for ADM degradation, inhibited the adventitial [ 3 H]-thymine incorporation induced by aldosterone. ADM inhibited the activity of extracellular signal related kinase (ERK) stimulated by aldosterone. Conclusion Aldosterone stimulates adventitia to produce and secrete ADM, which in turn, antagonizes the aldosterone-induced proliferation in adventitia.

To overcome “small sample size problem” problem faced by some hyper spectral classification methods, the Maximum Scatter Discriminant criterion is used to analyzed hyperspectral data. Maximum Scatter Discriminant analysis searches for the project axes by maximizing the difference of between-class scatter and within-class scatter matrices, which avoid to calculate the inverse of matrices. Experiment results on Indian Pines HSI data set show that the proposed method outperforms the other methods in terms of recognition accuracy. The proposed method is an effective and feasible method for hyper pectral data classification.

Adrenomedullin (ADM) is a multifunctional peptide with important roles in the cardiovascular system, especially in the adjustment of cardiovascular and renal homeostasis. ADM is present in plasma, organs and tissues, and its activity increases during hypertension. It remains unknown whether the clearance of this peptide is altered during hypertension. Neutral endopeptidase (NEP) is the major enzyme in ADM's degradation. We observed the activity and distribution of NEP and the expression of its mRNA in the plasma, cardiac ventricle, aorta, jejunum and kidney of spontaneously hypertensive rats (SHRs) in order to study the possible role of NEP in elevating tissue ADM concentrations during hypertension. ADM and NEP were diffuse in all tissues studied. The level of tissue ADM was generally higher in SHR tissues than in control tissues, except in the renal medulla, and its mRNA expression was higher in all tissues. Plasma NEP activity, general NEP activity and the expression of NEP mRNA in the left ventricle, aorta and jejunum in SHRs was lower than that of controls, and the level of ADM was inversely correlated with NEP activity. NEP activity and mRNA and protein expression in SHR kidneys were higher than in control kidneys; moreover, the ADM content was positively correlated with NEP activity in the renal cortex. NEP activity in the lung of SHRs did not differ from that of controls. Thus, in SHRs, the local concentration and action of ADM in the tissues may be differentially regulated by NEP.

Lysophosphatidic acid (LPA) is a bioactive phospholipid having growth factor-like activity on fibroblasts and is involved in cardiovascular diseases such as hypertension and heart failure by inducing vascular remodeling, characterized by fibroblast proliferation and migration in adventitia. Among various bioactive factors that LPA works with, adrenomedullin (ADM) is a multiple functional peptide with an important cytoprotective effect against cardiovascular damage. We studied rat aortic adventitia to explore the possible paracrine/autocrine interaction between endogenous ADM and LPA. LPA stimulation of the adventitia to secrete ADM and express its mRNA was concentration dependent. ADM inhibited LPA-induced proliferation in adventitial cells and attenuated the activity of mitogen-activated protein kinase (MAPK) stimulated by LPA. In contrast, treatment with specific antagonists of the ADM receptor potentiated the LPA-induced proliferation in adventitial cells. We concluded that LPA stimulates the adventitia to produce and secrete ADM, which in turn regulates the vascular biological effects of LPA.

Adrenomedullin (ADM) is a potent vasodilatory peptide which regulates blood pressure, cell growth and bone formation. Our work was aimed to explore the production of ADM, changes and pathophysiological significance of ADM mRNA and ADM receptor components--calcitonin receptor like receptor (CRLR) and receptor activity modifying proteins (RAMPs) mRNA in calcified myocardium and aorta of rats induced by Vitamin D3 plus nicotine. Contents of ADM in plasma, myocardium and aorta were measured by radioimmunoassay (RIA). The amount of ADM, CRLR and RAMPs mRNA was determined by semi-quantitative RT-PCR. The calcium content and alkaline phosphatase activity in myocardium and aorta of rats were measured. The results showed that the contents of calcium in calcified myocardium and aorta were increased by 3.5- and 6-fold (all P < 0.01), respectively, and alkaline phosphatases activity in calcified myocardium and aorta were increased by 66.5 and 82.7% (all P < 0.01 ), respectively, compared with control. Contents of ADM in plasma, myocardium and aorta were increased by 58% (P < 0.01), 14.3% (P < 0.01) and 27.8% P < 0.05). Furthermore, it was found that the amount of ADM, CRLR and RAMP2 mRNA in calcified myocardium was elevated by 90.6, 157.5 and 119.6% (all P < 0.01), RAMP3 mRNA was decreased by 14.1% (P < 0.01), respectively, compared with control. The amount of ADM, CRLR, RAMP2 and RAMP3 mRNA in calcified aorta was elevated by 37.7% (P < 0.01), 41.4% (P < 0.01), 60.1% (P < 0.05) and 13% P < 0.01), respectively, compared with control. The elevated level of CRLR and RAMP2 mRNA were in positive correlation with that of ADM mRNA (r = 0.992 and 0.882, respectively, P < 0.01) in calcified myocardium. The elevated level of CRLR and RAMP3 mRNA were also in positive correlation with that of ADM mRNA (r = 0.727, P < 0.05 and 0.816, P < 0.01, respectively) in calcified aorta. These results demonstrated that calcified myocardium and aorta generated an increased amount of ADM, up-regulated gene expressions of ADM, CRLR and RAMP2 mRNA. While the alteration of RAMP3 mRNA in calcified myocardium and aorta was different. These suggested that ADM and its receptor system might involve in the regulation of calcification in heart and aorta.

Adrenomedullin (ADM), a multifunction peptide with important roles in regulating cardiovascular homeostasis, has the vasodilatory properties and is of particular interest in the pathophysiology of sepsis. ADM levels in plasma and tissues are regulated by the proteolysis of neutral endopeptidase (NEP), the major enzyme of ADM degradation. We observed the NEP activity in the plasma, the activity and distribution of NEP and its mRNA expression in the tissues of rats in septic shock to study the possible role of NEP in elevating tissue ADM concentration during sepsis. ADM level increases progressively during sepsis except in the jejunum. Rats in early phase of shock (ES) showed diverse changes in tissue NEP activity. Plasma NEP activity, tissue NEP activity and its protein and mRNA expression in the left ventricle, aorta, jejunum and lung in the late phase of shock (LS) rats were lower than those in ES and the control, but no statistical change of NEP activity in the kidney was observed. The level of ADM was inversely correlated with NEP activity in the plasma, ventricle and aorta and positively correlated with NEP activity in the jejunum. Thus, in sepsis, the local concentration and action of ADM in tissues may be differentially regulated by NEP.