63 research outputs found
Application of Image Processing and Three-Dimensional Data Reconstruction Algorithm Based on Traffic Video in Vehicle Component Detection
Vehicle detection is one of the important technologies in intelligent video surveillance systems. Owing to the perspective projection imaging principle of cameras, traditional two-dimensional (2D) images usually distort the size and shape of vehicles. In order to solve these problems, the traffic scene calibration and inverse projection construction methods are used to project the three-dimensional (3D) information onto the 2D images. In addition, a vehicle target can be characterized by several components, and thus vehicle detection can be fulfilled based on the combination of these components. The key characteristics of vehicle targets are distinct during a single day; for example, the headlight brightness is more significant at night, while the vehicle taillight and license plate color are much more prominent in the daytime. In this paper, by using the background subtraction method and Gaussian mixture model, we can realize the accurate detection of target lights at night. In the daytime, however, the detection of the license plate and taillight of a vehicle can be fulfilled by exploiting the background subtraction method and the Markov random field, based on the spatial geometry relation between the corresponding components. Further, by utilizing Kalman filters to follow the vehicle tracks, detection accuracy can be further improved. Finally, experiment results demonstrate the effectiveness of the proposed methods
PA-X is a virulence factor in avian H9N2 influenza virus
H9N2 influenza viruses have been circulating worldwide in multiple avian species, and regularly infect pigs and humans. Recently, a novel protein, PA-X, produced from the PA gene by ribosomal frameshifting, was demonstrated to be an antivirulence factor in pandemic 2009 H1N1, highly pathogenic avian H5N1 and 1918 H1N1 viruses. However, a similar role of PA-X in the prevalent H9N2 avian influenza viruses has not been established. In this study, we compared the virulence and cytopathogenicity of H9N2 WT virus and H9N2 PA-X-deficient virus. Loss of PA-X in H9N2 virus reduced apoptosis and had a marginal effect on progeny virus output in human pulmonary adenocarcinoma (A549) cells. Without PA-X, PA was less able to suppress co-expressed GFP in human embryonic kidney 293T cells. Furthermore, absence of PA-X in H9N2 virus attenuated viral pathogenicity in mice, which showed no mortality, reduced progeny virus production, mild-to-normal lung histopathology, and dampened proinflammatory cytokine and chemokine response. Therefore, unlike previously reported H1N1 and H5N1 viruses, we show that PA-X protein in H9N2 virus is a pro-virulence factor in facilitating viral pathogenicity and that the pro- or antivirulence role of PA-X in influenza viruses is virus strain-dependent
Twenty amino acids at the C-terminus of PA-X are associated with increased influenza A virus replication and pathogenicity
The PA-X protein, arising from ribosomal frameshift during PA translation, was recently discovered in influenza A virus (IAV). The C-terminal domain ‘X’ of PA-X proteins in IAVs can be classified as full-length (61 aa) or truncated (41 aa). In the main, avian influenza viruses express full-length PA-X proteins, whilst 2009 pandemic H1N1 (pH1N1) influenza viruses harbour truncated PA proteins. The truncated form lacks aa 232–252 of the full-length PA-X protein. The significance of PA-X length in virus function remains unclear. To address this issue, we constructed a set of contemporary influenza viruses (pH1N1, avian H5N1 and H9N2) with full and truncated PA-X by reverse genetics to compare their replication and host pathogenicity. All full-length PA-X viruses in human A549 cells conferred 10- to 100-fold increase in viral replication and 5–8 % increase in apoptosis relative to corresponding truncated PA-X viruses. Full-length PA-X viruses were more virulent and caused more severe inflammatory responses in mice. Furthermore, aa 233–252 at the C terminus of PA-X strongly suppressed co-transfected gene expression by ∼50 %, suggesting that these terminal 20 aa could play a role in enhancing viral replication and contribute to virulence
Root hairs facilitate rice root penetration into compacted layers
Compacted soil layers adversely affect rooting depth and access to deeper nutrient and water resources, thereby impacting climate resilience of crop production and global food security. Root hair plays well-known roles in facilitating water and nutrient acquisition. Here, we report that root hair also contributes to root penetration into compacted layers. We demonstrate that longer root hair, induced by elevated auxin response during a root compaction response, improves the ability of rice roots to penetrate harder layers. This compaction-induced auxin response in the root hair zone is dependent on the root apex-expressed auxin synthesis gene OsYUCCA8 (OsYUC8), which is induced by compaction stress. This auxin source for root hair elongation relies on the auxin influx carrier AUXIN RESISTANT 1 (OsAUX1), mobilizing this signal from the root apex to the root hair zone. Mutants disrupting OsYUC8 and OsAUX1 genes exhibit shorter root hairs and weaker penetration ability into harder layers compared with wild type (WT). Root-hair-specific mutants phenocopy these auxin-signaling mutants, as they also exhibit an attenuated root penetration ability. We conclude that compaction stress upregulates OsYUC8-mediated auxin biosynthesis in the root apex, which is subsequently mobilized to the root hair zone by OsAUX1, where auxin promotes root hair elongation, improving anchorage of root tips to their surrounding soil environment and aiding their penetration ability into harder layers
Source-reservoir rock assemblages and hydrocarbon accumulation models in the Middle-Lower Jurassic of eastern Sichuan Basin, China
The eastern Sichuan Basin in China holds vast potential for oil and gas exploration in the Lower-Middle Jurassic strata. However, the geological characteristics and hydrocarbon accumulation patterns of this region remain largely unclear. During the deposition period of the Lower-Middle Jurassic strata, the eastern Sichuan is characterized by the formation of multiple sets of source, reservoir, and caprock assemblages through depositing lake-delta-fluvial deposits, which have great exploration potential. The Jurassic source rocks in eastern Sichuan are mainly developed in the Dongyuemiao Member, Da’anzhai Member, and Liangshan Formation. These source rocks have a total organic carbon (TOC) content greater than 1 and a varying range of organic matter maturity, with a Ro value of 0.8–2.0. The kerogen in these source rocks is primarily type II, with a smaller proportion being type III. A range of reservoir rocks can be found in the Jurassic strata of eastern Sichuan, with sandstone reservoirs being predominantly found in the Liangshan Formation, Shaximiao Formation, and Zhenzhuchong Member. Shale reservoirs are mostly present in the Dongyuemiao, Da’anzhai, Liangshan, and Maanshan Members, and there is a limited distribution of limestone reservoirs in the Da’anzhai Member and Dongyuemiao Formation. The arrangement of source rocks and reservoir rocks in eastern Sichuan has led to the formation of three types of reservoir-forming combinations, including lower generation and upper storage, self-generation and self-storage, and composite. Sandstone reservoirs are typically of lower generation and upper storage, shale reservoirs are primarily of self-generation and self-storage, and limestone reservoirs are mostly composite. The exploration of Jurassic oil and gas in eastern Sichuan should prioritize “layer and area selections.” The Da’anzhai, Dongyuemiao, and Liangshan shale reservoirs should be the primary exploration targets, with the semi-deep lake deposits in the syncline area being the most favorable. The degree of fracture development in the exploration area also has a significant impact on the shale oil and gas content. The Liangshan Formation and Shaximiao Formation sandstone reservoirs can serve as secondary exploration targets, with anticline areas that have better sealing conditions being more favorable. Limestone reservoirs have limited distribution, and exploration areas with high and steep fractures are relatively more advantageous
Design of reinforced concrete frame structure of exhibition hall
Import 23/08/2017Předmětem bakalářské práce je železobetonová dvoupatrová rámová konstrukce, která má sloužit pro občanskou vybavenost jako výstavní síň. Cílem je navrhnout a posoudit nosné prvky rámové konstrukce, konstrukce schodiště a stropů a založení na základových patkách podle metody mezních stavů, platných norem a konstrukčních zásad.
Pro posouzené prvky byly vypracovány výkresy výztuže a stavební výkresy.The subject of Bachelor thesis is two storey reinforced concrete frame structure, which has to serve for civil amenitied as exhibition hall. The aim is to design and assess the support elements of frame structure, the structure of staircase and the ceilings and the foundation on foundation plinths according to the method of limit states, applicable standards and design principles.
For assess elements have been created reinforcement drawings and constuction drawings.221 - Katedra konstrukcívýborn
Multifurnace optimization in electric smelting plants via load scheduling and control
For large electricity users, such as smelting plants, their electric loads cannot exceed a concerted limit in production. Traditional single-furnace optimization methods aim to satisfy the electric demand of a furnace to improve its production, and hence cannot consider the maximum demand constraint in a smelting plant. Maximum demand (MD) control is often utilized to keep the total electric demand within the limit via shedding the electric loads of some furnaces once the demand approaches the limit. However, the control method will enlarge the fluctuation of electric loads, which does harm to the production and causes a decline in energy-efficiency. In this paper, we propose a multifurnace optimization strategy to improve the production targets of a whole plant instead of a single furnace. In the strategy, an offline multiobjective load scheduling is first performed to assign electric loads for furnaces in each sampling period, taking into account of the MD constraint and production constraints. A multiobjective particle swarm optimization algorithm, combined with population initialization and constraint-handing strategies, is proposed to search for the Pareto optimal set of the scheduling problem, from which decision-makers can select one solution as the load scheduling program. A double closed-loop control mechanism is used to change the scheduled load into detailed load setpoints of furnaces and keep the actual loads up with the load setpoints. In the outer loop, the detailed load setpoints of furnaces are dynamically adjusted based on the deviation of actual loads from the scheduled loads. Thereafter, the desired setpoints are sent to the automatic control mechanism of each furnace, which is in the inner loop and responsible to keep the actual load up with the setpoint via a proportional-integral-derivative (PID) controller. The case study on a typical magnesia-smelting plant shows that the proposed multifurnace optimization strategy can achieve an increase of- about 12.29% in the production output, an improvement of about 0.46% of the magnesia in the product, and a slight reduction of 2.35% in electricity cost over the results of MD control
A multiobjective particle swarm optimization for load scheduling in electric smelting furnaces
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Electric smelting furnaces, applied in the smelting process of infusible mineral, are highly energy-intensive. In China, they waste a huge amount of electric energy, but yield a small quantity of valuable metals due to the lack of optimized load scheduling strategies. In this paper, we design a multiobjective load scheduling method to minimize the electricity cost and maximize the production output and product quality. Firstly a load scheduling model is developed based on a least square support vector machine, which is a robust empirical model with simple formulation and low sensitivity to external disturbance. We utilize a modified multiobjective particle swarm optimization algorithm to solve the optimization model. The proposed algorithm adopts a supervised population initialization that reuses the past optimal solutions and digs out new candidate solutions to guide the current optimization. An elaborate constraint-handing strategy is devised, which repairs the infeasible solutions that violate the maximum demand constraint and reserve the ones that violate one production constraint but performing excellently on the other production targets. The case study on a typical magnesia-smelting plant shows that the proposed multi-objective load scheduling model and algorithm can achieve an increase of about 14.5% in the production output, an improvement of about 0.46% of the magnesia in the product, and a slight saving in electricity cost
Numerical Simulation of the Flow and Heat Transfer Characteristics of Sweeping and Direct Jets on a Flat Plate with Film Holes
The internal heat transfer performance and flow structures of a sweeping jet and film composite cooling on a flat plate were numerically studied. Sweeping jet and film composite cooling consists of a fluidic oscillator and 20 cylindrical film holes; the direct jet is formed by removing the feedback from the fluidic oscillator, which is different from the traditional cylindrical nozzle. Four different mass flow rates of coolant were considered, and the inclination angle of the film hole was 30°. The Conjugate Heat Transfer method (CHT) and Unsteady Reynolds Averaged Navier Stokes equation (URANS) were employed. The results indicated that the flow resistance coefficients of the sweeping jet were larger than those of the direct jet, and the Nusselt number monotonously increased with the increase in the mass flow rate. Compared to the direct jet, the sweeping jet had a more spatially uniform heat removal rate, and the area-averaged Nusselt number was slightly lower. Therefore, the sweeping jet and film composite cooling caused the distribution of the flat plate heat transfer to be more uniform. It is worth noting that the novel direct jet nozzle in the present work had considerable area-averaged impingement cooling effectiveness
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