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Aiming at the present situation of laser aiming device in our country, a new type of laser aiming axis and parallel detection system of the transmission shaft is designed with CCD device and control technology. The system uses special signal processing and algorithm to improve the accuracy of the parallel degree of digital detection. Experimental results show that the detection system is stable and reliable, with high detection accuracy, and has high practicability and popularization value.

The quad-rotor is an under-actuated, strong coupled nonlinear system with many parameters, and the method of tuning them is very tough. For the sake of the stabilization of a quad-rotor, we propose the use of Particle Swarm Optimization (PSO) algorithm for tuning Linear Active Disturbance Rejection Control (LADRC) which is applied for the stabilization of a quad-rotor model. It is demonstrated that LADRC based on PSO algorithm has better flexibility, adaptability and robustness than that of trial and error method to determine parameters, and can improve the accuracy of the control system.

During the past decades, extensive coastal areas have been reclaimed along the coastline of China, including a massive land-reclamation activity in the early 1970s in the Yalu River Estuary (YRE). In this thesis, human impacts on sedimentation in the YRE are investigated by a combination of sediment core samples and numerical models. Three related studies were conducted on this topic after an analysis of the characteristics of the estuary and a comprehensive literature review. These studies quantitively demonstrate human impacts on the hydrodynamics and sediment transport in a macro-tidal estuary, provide an improved three-dimensional (3D) Lagrangian particle-tracking model for sediments and show the possibility of a new approach to study estuarine sediment sources using results from both numerical models and geochemistry. In the first study, sedimentary records from the YRE over the past five decades were used to establish a regional age framework and to investigate the influence of abnormal sedimentary events. Ten sediment core samples collected from the main branch in the estuary were analyzed for the first time. Core-averaged sediment accumulation rates calculated based on the 210Pb and 137Cs profiles of these samples were in the range 1.09–2.83 cm/yr and 0.94–3.11 cm/yr, respectively. The established age framework showed that most of the sediments in the YRE were deposited after the 1960s; this was also supported by results from a grain-size analysis. Changes in estuarine sedimentation due to abnormal events (e.g. floods, construction, deforestation and large mining activities) were also included in this study: (1) the mean grain size at sites near the Middle River became finer after 1963 due to the contemporaneous reduction in coarse sediment supply caused by upstream reservoir construction; (2) abnormal 137Cs signals in the records during the 1980s probably reflected concurrent deforestation; and (3) the 137Cs signals in the 1990s were related to mixing of sediments caused by mining activities. The feasibility of using 137Cs time markers (especially the auxiliary time markers in 1975 and 1986) in a dynamic estuary is confirmed in this study. Furthermore, the regional age framework established in this study can provide a chronological reference for future studies in the YRE and adjacent areas. The rare-earth-element (REE) signatures in sediments in two core samples (K1 and K12) and 51 surficial samples from the YRE were analyzed in the second study. Compared to samples from the western side of the estuary, the normalized pattern of REE at K1 and K12 relative to Upper Continental Crust (UCC) and North American Shale Composite (NASC) exhibited relatively strong enrichment in light REE (LREE) with remarkable change around 1975. According to the vertical profiles of concentration and fractionation factors of the NASC-normalized REE, the sedimentary environment of the core samples experienced dramatic change and subsequently becoming homogeneous after 1975. The binary diagram of the REE chemistry in the YRE and the discrimination function between the two cores also demonstrated that the properties of the deposits in K1 and K12 became similar after the 1970s. The sediments in this area were likely from multiple sources before the 1970s but turned into a uniform mixture after that. Such a deposition change appears to be related to human activity in this area, including the blocking of water channels and land reclamation around Chouduan Island. This study provides an important baseline for further studies about the sediment provenance and fates in the YRE and the Yellow Sea shelf. The results also reveal that anthropogenic interference can alter the sedimentary environment in a medium-scale estuary over a short period. The third study in this thesis analysed the mechanisms behind human-induced changes in estuarine sedimentation in the YRE using numerical simulations. A 3D coastal model was established for the area using the Finite Volume Coastal Ocean Model (FVCOM) to explore the changes in the hydrodynamics and sediment transport after land reclamation. Model results showed that the tidal system was flood-dominant both before and after the land reclamation, but the degree of flood dominance decreased slightly after the reclamation. Tidal-choking was enhanced in the main branch after reclamation, with a decreased tidal range, and resulted in stronger tidal currents. Both vertical and horizontal mixing were strengthened due to the enhanced tidal choking. As a consequence, sediments in the estuary became more well-mixed and homogeneous. Suspended-sediment concentration (SSC) in the estuary increased after the reclamation, and the horizontal gradient of SSC between the estuary and neighbouring shallow waters also became larger. The landward sediment flux caused by tidal pumping decreased significantly after the reclamation whereas the seaward Lagrangian flux increased. Furthermore, according to results from a newly improved 3D Lagrangian particle-tracking model, sediments at the two sites (K1 and K12) in the main branch were likely from different sources before the reclamation but were similar with a common composition of sediment afterwards; fluvial sediments and local resuspended sediments contributed more to sediments in the estuary and material from the Western Korean Bay was more restricted to outside the estuary after the reclamation. This study shows that tidal choking plays an important role in sediment dynamics in the YRE and that the estuary may turn into a sediment source instead of a sink if more land is reclaimed in the future. The conclusions of this study are valuable for marine management and show the utility of using a coastal model to resolve marine-geology problems.

Total suspended particulate matter (TSM) in estuarine and coastal regions usually exhibits significant diurnal and seasonal variability. The understanding of such variability can reveal the sedimentary processes in coastal turbid waters which play a central role in the water quality and primary productivity in the ocean. The aim of this study is to investigate the diurnal and seasonal variabilities of surface TSM distribution and its mechanisms in the Yalu River Estuary (YRE), Liaoning, China. Data from field measurements and polar-orbiting satellites with coarse spatial and limited temporal resolution are insufficient for monitoring surface TSM distribution in coastal waters. The Geostationary Ocean Color Imager (GOCI), the world's first geostationary ocean color satellite sensor, however, provides measurements over northeast Asia at hourly intervals. With regard to diurnal variability, there were usually two peaks of TSM in a tidal cycle corresponding to the maximum flood and ebb current. Tidal action appears to play a vital role in diurnal variability of TSM. Both the processes of tidal re-suspension and advection could be identified; however, the diurnal variability of TSM was mainly affected by a re-suspension process. In addition, special attention was paid to the effect of spring-neap tidal cycle on the TSM diurnal distribution. Scenarios under different daily tidal ranges implied that spring-neap tides can affect both the TSM values and the magnitude of TSM diurnal variability in the YRE: higher TSM concentrations with great fluctuation occurred during spring tide and TSM values were lower during neap tide with limited fluctuation. The GOCI-retrieved TSM results in the YRE showed a clearly seasonal variability of surface TSM during observation period, with the highest level in winter and the lowest in summer. A comparison between TSM results in the wet and dry seasons demonstrated that TSM concentrations were significantly higher in the dry season although river discharge was much greater in the wet season than the dry season. The seasonal variability of river discharge can only affect the TSM in the inner estuary during a flooding event. Seasonal action of wind waves was considered to be the main factor affecting TSM seasonal variability in the YRE.

Presentation given at the Satellite Oceanography Users Workshop, Melbourne, Australia, 9 -11 Nov 2015.

It is well known that ox-LDL plays key roles in the development of atherosclerosis, partly by inducing vascular smooth muscle cells (VSMCs) proliferation. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many physiological and pathological conditions. However, the role and function of miRNAs on ox-LDL induced VSMC proliferation are not fully elucidated. In this study, we showed that ox-LDL could suppress miR-141 expression and inhibition of miR-141 could promote VSMCs proliferation. Moreover, we found that PAPPA was the direct target gene of miR-141. Overexpression of PAPPA impaired the miR-141-induced inhibition of proliferation in the VSMCs. Taken together; miR-141 may play important roles in ox-LDL-induced abnormal proliferation of the VSMC.

In this paper, we apply the maximum principle and the compensated compactness method to get the existence of weak solutions to the Cauchy problems for the nonlinear hyperbolic conservation laws of quadratic flux and the LeRoux system with sources. En este artículo aplicamos el principio del máximo y el método de la compactificación compensada para obtener soluciones débiles a los problemas de Cauchy para las leyes de conservación hiperbólica, no lineal, de flujo cuadrático y el sistema LeRoux con fuentes.

In this paper we use the Brouwer-Schauder's fixed point theorem to obtain the existence of local smooth viscosity solutions of the Cauchy problem for the parabolic system with the bounded measurable initial data Then based on the local existence and the maximum principle, we get the existence of global smooth solutions for two special systems, one related to the hyperbolic system of quadratic flux and the other related to the LeRoux system. En este artículo usamos el teorema de punto fijo de Brouwer-Schauder para obtener la existencia de soluciones locales de viscosidad suave al problema de Cauchy para el sistema parabólico con data inicial medible acotada Luego, basados en la existencia local y el principio del máximo, obtenemos la existencia de soluciones globales suaves para dos sistemas especiales , uno relacionado con el sistema parabólico de flujo cuadrático y el otro relacionado con el sistema LeRoux.

In this paper, we apply the invariant region theory [1] and the compensated compactness method [2] to study the singular limits of stiff relaxation and dominant diffusion for the Cauchy problem of a system of quadratic flux and the Le Roux system, and obtain the convergence of the solutions to the equilibrium states of these systems. En este artículo aplicamos la teoría de la región invariante [1] y el método de la compactificación compensada [2] para estudiar los límites singulares de la relajación rígida y difusión dominante para el problema de Cauchy de un sistema de flujo cuadrático y el sistema Roux obteniendo la convergencia de las soluciones para el estado de equilibrio de esos sistemas.