A COMPARISON OF HAZE REMOVAL ALGORITHMS AND THEIR IMPACTS ON CLASSIFICATION ACCURACY FOR LANDSAT IMAGERY

The quality of Landsat images in humid areas is considerably degraded by haze in terms of their spectral response pattern, which limits the possibility of their application in using visible and near-infrared bands. A variety of haze removal algorithms have been proposed to correct these unsatisfactory illumination effects caused by the haze contamination. The purpose of this study was to illustrate the difference of two major algorithms (the improved homomorphic filtering (HF) and the virtual cloud point (VCP)) for their effectiveness in solving spatially varying haze contamination, and to evaluate the impacts of haze removal on land cover classification. A case study with exploiting large quantities of Landsat TM images and climates (clear and haze) in the most humid areas in China proved that these haze removal algorithms both perform well in processing Landsat images contaminated by haze. The outcome of the application of VCP appears to be more similar to the reference images compared to HF. Moreover, the Landsat image with VCP haze removal can improve the classification accuracy effectively in comparison to that without haze removal, especially in the cloudy contaminated area

Research on the value-added path and management mechanism of the whole agricultural industry chain based on the value network

The key to fostering the growth and prosperity of China's rural industry is to realize the added value of the entire industrial chain. This article focuses primarily on enhancing the value of the entire agricultural supply chain. Based on a systematic analysis of the existing value-added methods of agriculture and the theory of the entire industry chain and value network, it combines the multifunctional and multidimensional value attributes of the entire agricultural industry—the entire farming industry—under the value network. And put forward the value reconstruction network system and value-added method of "platform ecosystem + agricultural industry cluster," information resource optimization and integration, cultural value fusion, knowledge creation, and information resource sharing, value Internet relationship management, information virtual value chain management, and utilization of Internet technology innovation for driving value chain mechanism, etc., can promote the value-added effectively. Rejuvenate and expand the entire agricultural supply chain. For operation research to help ensure the future success of agricultural value chains, practitioners must comprehend and model the value chain as a complex adaptive system.Lei Chaofan (Management and Science University), Zunirah Mohd Talib (Graduate School of Management, Postgraduate Centre, Management and Science University), Liang Ruihua (Academic Committee, Henan University of Technology), Brian Sheng-Xian Teo (Graduate School of Management, Academic Affairs Department, Management and Science University)Includes bibliographical reference

Isotopic Composition (δ¹⁵N and δ¹⁸O) of Urban Forests in Different Climate Types Indicates the Potential Influences of Traffic Exhaust and Relative Humidity

Previous studies have shown that climatic and anthropogenic factors influence the variations in the stable isotope signature of tree materials in an urban ecosystem. However, the responses of urban trees to various anthropogenic and precipitation interventions are unclear. To fill the research gap, the isotopic composition (δ15N and δ18O) and total nitrogen content of the soil-plant system of urban forests were measured, focusing on typical urban tree species (Populus tomentosa and Ficus virens). The research was done under various land uses in China’s Beijing and Shenzhen megacities (with different humidity conditions). The linear mixed-effect model revealed that the δ15N values in the leaves of roadside Ficus virens were significantly higher than those in urban park sites, away from the road (δ15N difference = 7.2‰). In contrast, Populus tomentosa leaves exhibited a non-significant difference (δ15N difference = −1.8‰). Further regression analysis revealed that the variations in δ15N in tree leaves could be attributed to the proximity to highways, suggesting the influence of vehicle exhaust on δ15N values in roadside trees. The linear mixed-effect model also revealed δ18O values significantly higher in Populus tomentosa leaves than in Ficus virens leaves. To assess the influence of humidity conditions on δ18O values in the leaves, the ratio of the atmospheric and intercellular vapor pressures (ea/ei) of tree canopies was estimated. The result revealed that the ea/ei of Ficus virens was significantly higher than for Populus tomentosa, ascribed to the variation in the humidity conditions of the two megacities. These results highlight that urban trees can potentially serve as bioindicators for atmospheric pollution and humidity. Our findings highlight the ecophysiological responses of urban forests related to N and O as they vary according to traffic exhaust and relative humidity. Consequently, they are potentially valuable indicators of urban atmospheric contamination, forming a nature-based solution for citizen welfare improvement

Pore scale numerical investigation of counter-current spontaneous imbibition in multi-scaled pore networks

The multi-scaled pore networks of shale or tight reservoirs are considerably different from the conventional sandstone reservoirs. After hydraulic fracturing treatment, the spontaneous imbibition process plays an important role in the productivity of the horizontal wells. Applying the color-gradient model of Lattice Boltzmann Method (LBM) accelerated with parallel computing, we studied the countercurrent spontaneous imbibition process in two kinds of pore structures with different interlacing distributions of large and small pores. The effect of geometry configuration of pore arrays with different pore-scale and the capillary number Ca on the mechanism of counter-current spontaneous imbibition as well as the corresponding oil recovery factor are studied. We found that the wetting phase tends to invade the small pore array under small Ca in both types of geometry configurations of different pore arrays of four pore arrays zones. The wetting phase also tends to invade the pore array near the inlet for injecting the wetting phase no matter if it is a large pore array or small pore array except for the situation when the Ca is large to a certain value. In this situation, the small pore arrays show resistance to the wetting phase, so the wetting phase doesn't invade the small pore near the inlet, but invades the large pore preferentially. Both the geometry configurations of different pore arrays and Ca have a significant effect on the oil recovery factor. This work will help to solve the doubt about the selectivity of the multi-scaled pores of the wetting phase and the role of pores with different sizes in imbibition and oil draining in countercurrent spontaneous imbibition processes

Numerical Modeling of Seismic Responses and Seismic Measures of Tunnel Crossing a Fault Zone: A Case Study

The investigation shows that Longxi Tunnel, across a fault zone, was severely damaged during the 2008 Wenchuan earthquake, China. In this paper, the dynamic time history analysis method is used to study the seismic response characteristics of Longxi Tunnel and the aseismic effect of seismic measures. The interfaces of the fault are simulated by bonded interfaces. The results show that high earthquake intensity, high in situ stress, and fault zone are the main reasons for damage of Longxi Tunnel. The inconsistent motion response between the normal surrounding rocks and surrounding rocks within the fault zone resulted in the damage of Longxi Tunnel, and the maximum displacement difference reaches 50 cm. With the seismic measure by setting shake absorb layer and seismic joints, the tunnel has better performance: the maximum peak internal force of the tunnel structure is reduced by about 26% and the acceleration is reduced by 30%. Seismic measures should not only be considered within fault zones but also extend to adjacent surrounding rocks. In this study, the fault seismic measures of Longxi Tunnel should be no less than 4.0 times the tunnel diameter

A COMPARISON OF HAZE REMOVAL ALGORITHMS AND THEIR IMPACTS ON CLASSIFICATION ACCURACY FOR LANDSAT IMAGERY

The quality of Landsat images in humid areas is considerably degraded by haze in terms of their spectral response pattern, which limits the possibility of their application in using visible and near-infrared bands. A variety of haze removal algorithms have been proposed to correct these unsatisfactory illumination effects caused by the haze contamination. The purpose of this study was to illustrate the difference of two major algorithms (the improved homomorphic filtering (HF) and the virtual cloud point (VCP)) for their effectiveness in solving spatially varying haze contamination, and to evaluate the impacts of haze removal on land cover classification. A case study with exploiting large quantities of Landsat TM images and climates (clear and haze) in the most humid areas in China proved that these haze removal algorithms both perform well in processing Landsat images contaminated by haze. The outcome of the application of VCP appears to be more similar to the reference images compared to HF. Moreover, the Landsat image with VCP haze removal can improve the classification accuracy effectively in comparison to that without haze removal, especially in the cloudy contaminated are

Coupling Efficiency Assessment of Food–Energy–Water (FEW) Nexus Based on Urban Resource Consumption towards Economic Development: The Case of Shenzhen Megacity, China

The population aggregation and economic development caused by urbanization significantly influence the efficiency of urban resource consumption. However, the coupling interactions between crucial resource consumptions such as food, energy and water (FEW) and urbanization processes within highly urbanized areas has not been well-studied. In this study, we constructed an assessment framework for the coupling efficiency measurement of FEW resource consumptions in 10 administrative districts across Shenzhen megacity during 2012–2020, based on the data envelopment analysis (DEA). This study demonstrated that, from the perspective of the FEW nexus, increasing efficiencies in the energy consumption of most districts improved the municipal FEW efficiency, while more than half of the districts did not achieve water resource efficiencies throughout the period. Concerning regional economic development, 80% of the districts improved coupling FEW efficiencies by 2020, the average values of which were higher for Yantian, Nanshan, Luohu and Dapeng, and lower for Baoan, Longgang and Guangming, with a downtrend only being observed in Guangming. Overall, the value of the coupling FEW efficiency of Shenzhen megacity rose by 35% from 2012 to 2020. Correlation analysis showed that synergistic effects of efficient resource consumption occurred in most districts, and economic urbanization was the main driving factor of regional FEW efficiencies within Shenzhen megacity. This study provides instructive insights into the status of urban resource consumption and suggests that the coordination of FEW management should be further improved by fiscal intervention to maintain economic development with the limited resources available, which would have valuable implications for synergistic FEW governance in megacities in China and elsewhere

Spatio-Temporal Variation in Bird Assemblages in a Subtropical Urban Ecosystem

Background: Being an excellent indicator of habitat quality, birds are more and more popular in urban studies. Selective impacts of urban environments on avian communities have been repeatedly demonstrated, however, limited information is available under a spatial-temporal perspective, especially for subtropical young cities. Methods: Bird communities were surveyed and environmental data were collected in different types of urban green spaces surrounded by urban matrix during 2018 and 2019. Various statistical analyses were used to describe avian communities residing in different habitats and evaluate bird–environment relationships. Results: Avian community structure differed between major habitat types. At intensely urbanized roadside green spaces sites, omnivores dominated over insectivores, which were regional dominators. Woodland area was key in all urban habitat types, however, the importance decreased with increasing woodland size. Bird species richness in residential parks and individual abundance in roadside green spaces were negatively influenced by environmental noise and visitor density, respectively. Resident bird species and individuals dominated over migrants, and municipal parks presented higher species richness and abundance than other habitat types during winter. Conclusions: Highly simplified habitats in urban areas represent poor wintering habitats, whereas municipal parks served as key refugia. Continued urbanization will place further pressure on habitats which are more natural; thus, municipal parks and other natural habitats must be protected to construct sustainable human-coupled ecosystems

The Evaluation of Water Footprints and Sustainable Water Utilization in Beijing

The water footprint approach is superior to the traditional approaches applied in water management. The water footprint can be regarded as a comprehensive indicator of freshwater resources appropriation, next to the traditional and restricted measure of water withdrawal. This study took the megacity of Beijing in North China as a case study to evaluate the sustainability of water utilization by calculating the water footprint in 2007 and 2010, based on real and virtual water consumption. The results show that the water footprint of the inhabitants of Beijing is decreasing, while the degree of water import dependency is increasing. Although the pressure of water scarcity in Beijing was slightly alleviated, the current situation of water shortage remains an enormous challenge, as the water footprint per capita is nearly 10 times higher than the water resources available. Therefore, water utilization in Beijing remains unsustainable. The improvement of water resources utilization efficiency, that encompasses water saving, is proposed as a key measure in the mitigation of water shortage

A Cerberus-Nodal-Lefty-Pitx signalling cascade controls Left-Right asymmetry in amphioxus

Many bilaterally symmetrical animals develop genetically-programmed left-right asymmetries. In vertebrates this process is under the control of Nodal signalling, which is restricted to the left side of the body by the Nodal antagonists Cerberus and Lefty. Amphioxus, the earliest diverging chordate lineage, has profound left-right asymmetry as a larva. We show that Cerberus, Nodal, Lefty and their target transcription factor Pitx are sequentially activated in amphioxus embryos. We then address their function by TALEN-based knockout and HSP promoter-driven overexpression. Knockout of Cerberus leads to ectopic right-sided expression of Nodal, Lefty and Pitx, while over expression of Cerberus represses their left-sided expression. Overexpression of Nodal in turn represses Cerberus, and activates Lefty and Pitx ectopically on the right side. We also show Lefty represses Nodal, while Pitx activates Nodal. These data combine in a model in which Cerberus determines whether the left-sided gene expression cassette is activated or repressed. We also show these regulatory steps are essential for normal left-right asymmetry to develop, as when they are disrupted embryos may instead form two phenotypic left sides or two phenotypic right sides. Our study shows the full regulatory cassette controlling left-right asymmetry was in place in the ancestor of amphioxus and vertebrates. This includes the deployment of the Nodal inhibitors Cerberus and Lefty, both of which operate in feedback loops with Nodal and combine to establish asymmetric Pitx expression. Cerberus and Lefty are missing from most invertebrate lineages, marking this mechanism as an innovation in the lineage leading to modern chordates