An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control...An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.展开更多
In the capacity planning of hydro-wind-solar power systems(CPHPS),it is crucial to use flexible hydropower to complement the variable wind-solar power.Hydropower units must be operated such that they avoid specific re...In the capacity planning of hydro-wind-solar power systems(CPHPS),it is crucial to use flexible hydropower to complement the variable wind-solar power.Hydropower units must be operated such that they avoid specific restricted operation zones,that is,forbidden zones(FZs),to avoid the risks associated with hydropower unit vibration.FZs cause limitations in terms of both the hydropower generation and flexible regulation in the hydro-wind-solar power systems.Therefore,it is essential to consider FZs when determining the optimal wind-solar power capacity that can be compensated by the hydropower.This study presents a mathematical model that incorporates the FZ constraints into the CPHPS problem.Firstly,the FZs of the hydropower units are converted into those of the hydropower plants based on set theory.Secondly,a mathematical model was formulated for the CPHPS,which couples the FZ constraints of hydropower plants with other operational constraints(e.g.,power balance constraints,new energy consumption limits,and hydropower generation functions).Thirdly,dynamic programming with successive approximations is employed to solve the proposed model.Lastly,case studies were conducted on the hydro-wind-solar system of the Qingshui River to demonstrate the effectiveness of the proposed model.展开更多
In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two t...In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel.展开更多
The self-organization mapping (SOM) neural network algorithm is a new method used to identify the ecosystem service zones at regional extent. According to the ecosystem assessment framework of Millennium Ecosystem A...The self-organization mapping (SOM) neural network algorithm is a new method used to identify the ecosystem service zones at regional extent. According to the ecosystem assessment framework of Millennium Ecosystem Assessment ( MA), this paper develops an indicator system and conducts a spatial cluster analysis at the 1km by I km grid pixel scale with the SOM neural network algorithm to sort the core ecosystem services over the vertical and horizontal dimensions. A case study was carried out in Xilingol League. The ecosystem services in Xilingol League could be divided to six different ecological zones. The SOM neural network algorithm was capable of identifying the similarities among the input data automatically. The research provides both spatially and temporally valuable information targeted sustainable ecosystem management for decision-makers.展开更多
With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers sui...With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers suitable for underground environment have been studied based on the biochemical characterization and denitrifying mechanism of microorganisms. Then the nitrate-eliminating modeling study in soil columns was carried out with the obtained denitrifier. The results show that the nitrate-eeliminating efficiency can reach 98%,so it has practical value in controlling nitrate pollution in water systems.展开更多
To know the bacterial communities structure in Babylonia areolata culture systems and to research and optimize the management pattem of Babylonia areola-ta culture systems of the pond mulched plastic film and sand in ...To know the bacterial communities structure in Babylonia areolata culture systems and to research and optimize the management pattem of Babylonia areola-ta culture systems of the pond mulched plastic film and sand in bottom, the bacte- rial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom were analyzed at molecular level by adopting the denaturing gradient gel electrophoresis (DGGE). The results indicated that the dominant bacterial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom, which were built on the basis of the seawater in East-island of Zhanjiang, included Proteobac- teda Chloroflexi, Cyanobacteria and Actinobacteria. The dominant bacterial groups in the above pond culture system were Garnmaproteobacteria, Alphaproteobacteria, Deltaprotecbacteda, Epsilonproteobacteda, Anaerolineae, Cyanobacteria and Acti- nobacteda. The dominant bacterial communities in the subtidal zone culture system were Gammaprotecbacteda, Alphaproteobacteria, Deltaproteobacteria, Anaerolineae and Cyanobacteda, and there were less Epsilonproteobacteria and Actinobacteria in the culture system. The higher diversity was detected in the above two culture sys- tems. The results of unweighted pair group method with arithmetic average (UPG- MA) showed that the bacterial communities of the sediment samples S1 and S2 in the above two culture systems were a cluster, the similarity of bacterial communities was 54.5%. The bacterial communities of seawater samples S3 and S4 in the above culture systems were in clusters, and the similarity of the bacterial communi- ties was 84.0%. The results showed that the microorganism ecological level in the Babylonia areolata culture systems of the pond mulched plastic film and sand in bottom could be similar to the sub-tidal zone culture systems through changing the pond seawater and monitoring the microbial population.展开更多
The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological securit...The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored.展开更多
The coastal ecosystem health assessment is a field of increasing importance.In this paper,a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made,mainly based on remote sensing data and GI...The coastal ecosystem health assessment is a field of increasing importance.In this paper,a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made,mainly based on remote sensing data and GIS technique.Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development.Firstly,human activities,hydrology and ecosystem problems in the study area were discussed and analyzed.Secondly,from 4 aspects of human stress,physical,chemical and biological responses to anthropogenic activities and natural stress,several indicators such as water transparency(Secchi Disk Depth,SDD),suspended substance concentration,dissolved inorganic nitrogen,active phosphate,chlorophyll,harmful algae bloom,as well as distribution of sewage,sea lanes and port were employed.Thirdly,the Analytic Hierarchical Process was used for indicator weight calculation,and the ecosystem health criteria were established according to the integrative analysis of national water quality criteria,similar coastal ecosystem health research in other places or data inherent properties.The results indicated that from 2005 to 2007 the coastal water ecosystem health value in Zhejiang Province was unhealthy and needs ecological restoration by human intervention.展开更多
Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest Chin...Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality (2-3 orders of magnitude at the intersection zone) and the formation mechanisms of the fault intersection zone. Differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized.展开更多
China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic ...China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic development and modern management.Laying a theoretical foundation for the modern management of China's costal zone is aimed at. This research focuses on the following processing and analyzing technologies for coastal zone high-resolution remote sensing data: organization and management of large amounts of high-resolution remote sensing data, quick and precise spatial positioning system,algorithms for image fusion in feature level and coastal zone feature extraction. They will form a technical foundation of the system. And, if combined with other research results such as coastal zone remote sensing classification system and its mapping subsystem, an advanced technical frame for remote sensing investigation of coastal zone resource will be constructed.展开更多
In this paper we use theoretical analysis and extensive simulations to study zone inhomogeneity with the random asymmetric simple exclusion process (ASEP). In the inhomogeneous zone, the hopping probability is less ...In this paper we use theoretical analysis and extensive simulations to study zone inhomogeneity with the random asymmetric simple exclusion process (ASEP). In the inhomogeneous zone, the hopping probability is less than 1. Two typical lattice geometries are investigated here. In case A, the lattice includes two equal segments. The hopping probability in the left segment is equal to 1, and in the right segment it is equal to p, which is less than 1. In case B, there are three equal segments in the system; the hopping probabilities in the left and right segments are equal to 1, and in the middle segment it is equal to p, which is less than 1. Through theoretical analysis, we can discover the effect on these systems when p is changed.展开更多
Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in co...Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in complex patterns. Here I describe some of our observations and experiments showing that mycorrhizal fungi play key roles in moving water for both transpiration and to facilitate nutrient acquisition under dry conditions. Mycorrhizal fungal hyphae grow from both surface and deep roots even into bedrock to help extract water under dry conditions. In both deep and surface roots, mycorrhizal fungi acquire water from pores too small for roots and root hairs to access, and at distances from roots and root hairs. Mycorrhizal fungi are also able to utilize hydraulic-lifted water from plants to obtain nutrients in extremely dry surface soils. The importance of these root symbionts in water and nutrient dynamics, and as integrators of surface and deeper water dynamics need further investigation.展开更多
To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feat...To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management.展开更多
Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in t...Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in the Tongbai-Dabie complexes. However, it cannot explain the most deformations in the shear zones. The northwest-southeast shear zones are developed around or wrapped the Tongbai-Dabie complexes. They play an important role for the interpretation of the tectonic evolution of the Tongbai-Dabie orogenic belt. By a systematically observation and description of the geometry and kinematics of these shear zones, we found that the shear zones to the north dip NE and have a uniform sinistral shear sense, the shear zone to the south dips SW and has a uniform dextral shear sense, and the shear zones at the core are sub-horizontal and have a uniform top-to-NW sense of shear. Combining with the comparison of previous and our geochronological studies, we interpret these associations as indicating that these shear zones were originally a single, more flat-lying and sub- horizontal shear zone with a uniform top-to-NW shear sense before the folding-doming of the Tongbai- Dabie complexes and suggest that the Tongbai-Dabie orogenic belt experienced a uniform top-to-NW orogen-paraUel extension in the ductile lithosphere before the widespread magmatism in the Cretaceous.展开更多
The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the ...The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the balance of number of kinds of items between different zones but not the number of items and the idle time in each zone. In this paper, an idle factor is proposed to measure the idle time exactly. The idle factor is proven to obey the same vary trend with the idle time, so the object of this problem can be simplified from minimizing idle time to minimizing idle factor. Based on this, the model of item assignment problem in synchronized zone automated order picking system is built. The model is a form of relaxation of parallel machine scheduling problem which had been proven to be NP-complete. To solve the model, a taboo search algorithm is proposed. The main idea of the algorithm is minimizing the greatest idle factor of zones with the 2-exchange algorithm. Finally, the simulation which applies the data collected from a tobacco distribution center is conducted to evaluate the performance of the algorithm. The result verifies the model and shows the algorithm can do a steady work to reduce idle time and the idle time can be reduced by 45.63% on average. This research proposed an approach to measure the idle time in synchronized zone automated order picking system. The approach can improve the picking efficiency significantly and can be seen as theoretical basis when optimizing the synchronized automated order picking systems.展开更多
The Sanchahe quartz monzonite intrusion is situated in the middle segment of the North Qinling tectonic belt, Central China mainland, and consists chiefly of sanukitoid–like and granodioritic-monzogranitic rocks. The...The Sanchahe quartz monzonite intrusion is situated in the middle segment of the North Qinling tectonic belt, Central China mainland, and consists chiefly of sanukitoid–like and granodioritic-monzogranitic rocks. The sanukitoid–like rocks are characterized by quartz monzonites, which display higher Mg#(55.0–59.0), and enrichments in Na2 O+K2 O(7.28–8.94 %), Ni(21-2312 ppm), Cr(56-4167 ppm), Sr(553-923 ppm), Ba(912-1355 ppm) and LREE((La/Yb)N =9.47–15.3), from negative to slightly positive Eu anomalies(δEu=+0.61 to +1.10), but also depletion in Nb, Ta and Ti. The granodioritic-monzogranitic rocks diaplay various Mg#of 6.00-53.0, high Na2 O+K2 O(7.20– 8.30%), Sr(455–1081 ppm) and(La/Yb)N(27.6–47.8), with positive Eu anomalies(δEu=1.03–1.57) and depleted Nb, Ta and Ti. Laser ablation inductively coupled plasma mass spectrometry(LA-ICPMS) zircon U-Pb isotopic dating reveals that the sanukitoid-like rocks were emplaced at two episodes of magmatism at 457±3 Ma and 431±2 Ma, respectively. The monzogranites were emplaced at 445±7Ma. Sanukitoid–like rocks have their εHf(t) values ranging from +0.3 to +15.1 with Hf–depleted mantle model ages of 445 to 1056 Ma, and the monzogranite shows its εHf(t) values ranging from 21.6 to +10.8 with Hf–depleted mantle model ages of 635 to 3183 Ma. Petrological, geochemical and zircon Lu –Hf isotopic features indicate that the magmatic precursor of sanukitoid–like rocks was derived from partial melting of the depleted mantle wedge materials that were metasomatized by fluids and melts related to subduction of oceanic slab, subsequently the sanukitoid magma ascended to crust level. This emplaced mantle magma caused partial melting of crustally metamorphosed sedimentary rocks, and mixing with the crustal magma, and suffered fractional crystallization, which lead to formations of quartz monzonites. However, the magmatic precursor of the granodioritic-monzogranitic rocks were derived from partial melting of subducted oceanic slab basalts. Integrated previous investigation for the adackitic rocks in the south of the intrusion, the Sanchahe intrusion signed that the North Qinling tectonic zone was developed in an early Paleozoic transitionally tectonic background from an island arc to back–arc.展开更多
Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynami...Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.展开更多
The aim of the current study was to gain a better understanding of the changes in soil microbial biomass and basal respiration dynamics in the vicinity of the bean caper (Zygophyllura duraosura) perennial desert shr...The aim of the current study was to gain a better understanding of the changes in soil microbial biomass and basal respiration dynamics in the vicinity of the bean caper (Zygophyllura duraosura) perennial desert shrub and the inter-shrub sites. Microbial biomasses as well as basal respiration were found to be significantly greater in the soil samples taken beneath the Z. duraosura shrubs than from the inter-shrub sampling sites, with no differences between the two sampling layers (0-10 and 10-20 cm) throughout the study period. However, seasonal changes were observed due to autumn dew formation, which significantly affected microbial biomass and basal respiration in the upper-layer inter-shrub locations. The calculated metabolic coefficient (qCO2) revealed significant differences between the two sampling sites as well as between the two soil layers, elucidating the abiotic effect between the sites throughout the study period. The substrate availability index was found to significantly demonstrate the differences between the two sites, elucidating the significant contribution of Z. duraosura in food source availability and in moderating harsh abiotic components. The importance of basal microbial parameters and the derived indices as tools demonstrated the importance and need for basic knowledge in understanding plant-soil interactions determined by an unpredictable and harsh desert environment.展开更多
A systematic account of micro-textures and a few compositional profiles of plagioclase from high-alumina basaltic aa lava erupted during the year 1994-1995, from Barren Island Volcano, NE India ocean, are presented fo...A systematic account of micro-textures and a few compositional profiles of plagioclase from high-alumina basaltic aa lava erupted during the year 1994-1995, from Barren Island Volcano, NE India ocean, are presented for the first time. The identified micro-textures can be grouped into two categories: (i) Growth related textures in the form of coarse/fine-sieve morphology, fine-scale oscillatory zoning and resorption surfaces resulted when the equilibrium at the crystal-melt interface was fluctuated due to change in temperature or H20 or pressure or composition of the crystallizing melt; and (ii) morphological texture, like glomerocryst, synneusis, swallow-tailed crystal, microlite and broken crystals, formed by the influence of dynamic behavior of the crystallizing magma (convection, turbulence, degassing, etc.). Each micro-texture has developed in a specific magmatic environment, accordingly, a first order magma plumbing model and crystallization dynamics are envisaged for the studied lava unit. Magma generated has undergone extensive fractional crystallization of An-rich plagioclase in stable magmatic environment at a deeper depth. Subsequently they ascend to a shallow chamber where the newly brought crystals and pre-existing crystals have undergone dynamic crystallization via dissolution-regrowth processes in a convective self- mixing environment. Such repeated recharge-recycling processes have produced various populations of plagioclase with different micro-textural stratigraphy in the studied lava unit. Intermittent degassing and eruption related decompression have also played a major role in the final stage of crystallization dynamics.展开更多
基金financially supported by the Sichuan Science and Technology Program(Grant No.2023NSFSC1980)。
文摘An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.
文摘In the capacity planning of hydro-wind-solar power systems(CPHPS),it is crucial to use flexible hydropower to complement the variable wind-solar power.Hydropower units must be operated such that they avoid specific restricted operation zones,that is,forbidden zones(FZs),to avoid the risks associated with hydropower unit vibration.FZs cause limitations in terms of both the hydropower generation and flexible regulation in the hydro-wind-solar power systems.Therefore,it is essential to consider FZs when determining the optimal wind-solar power capacity that can be compensated by the hydropower.This study presents a mathematical model that incorporates the FZ constraints into the CPHPS problem.Firstly,the FZs of the hydropower units are converted into those of the hydropower plants based on set theory.Secondly,a mathematical model was formulated for the CPHPS,which couples the FZ constraints of hydropower plants with other operational constraints(e.g.,power balance constraints,new energy consumption limits,and hydropower generation functions).Thirdly,dynamic programming with successive approximations is employed to solve the proposed model.Lastly,case studies were conducted on the hydro-wind-solar system of the Qingshui River to demonstrate the effectiveness of the proposed model.
文摘In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel.
基金Supported by the National Scientific Foundation of China(4080123170873118)+6 种基金the Chinese Academy of Sciences(KZCX2-YW-305-2KSCX2-YW-N-039KZCX2-YW-326-1)the Ministry of Science and Technology of China(2006DFB91912012006BAC08B032006BAC08B062008BAK47B02)~~
文摘The self-organization mapping (SOM) neural network algorithm is a new method used to identify the ecosystem service zones at regional extent. According to the ecosystem assessment framework of Millennium Ecosystem Assessment ( MA), this paper develops an indicator system and conducts a spatial cluster analysis at the 1km by I km grid pixel scale with the SOM neural network algorithm to sort the core ecosystem services over the vertical and horizontal dimensions. A case study was carried out in Xilingol League. The ecosystem services in Xilingol League could be divided to six different ecological zones. The SOM neural network algorithm was capable of identifying the similarities among the input data automatically. The research provides both spatially and temporally valuable information targeted sustainable ecosystem management for decision-makers.
文摘With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers suitable for underground environment have been studied based on the biochemical characterization and denitrifying mechanism of microorganisms. Then the nitrate-eliminating modeling study in soil columns was carried out with the obtained denitrifier. The results show that the nitrate-eeliminating efficiency can reach 98%,so it has practical value in controlling nitrate pollution in water systems.
基金Supported by the Special Program of Scientific and Technological Promotion of Fisheries in Guangdong(A201101I01,A201208E01)the Guangdong Scientific and Technological Planning Program(2012B020415006)~~
文摘To know the bacterial communities structure in Babylonia areolata culture systems and to research and optimize the management pattem of Babylonia areola-ta culture systems of the pond mulched plastic film and sand in bottom, the bacte- rial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom were analyzed at molecular level by adopting the denaturing gradient gel electrophoresis (DGGE). The results indicated that the dominant bacterial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom, which were built on the basis of the seawater in East-island of Zhanjiang, included Proteobac- teda Chloroflexi, Cyanobacteria and Actinobacteria. The dominant bacterial groups in the above pond culture system were Garnmaproteobacteria, Alphaproteobacteria, Deltaprotecbacteda, Epsilonproteobacteda, Anaerolineae, Cyanobacteria and Acti- nobacteda. The dominant bacterial communities in the subtidal zone culture system were Gammaprotecbacteda, Alphaproteobacteria, Deltaproteobacteria, Anaerolineae and Cyanobacteda, and there were less Epsilonproteobacteria and Actinobacteria in the culture system. The higher diversity was detected in the above two culture sys- tems. The results of unweighted pair group method with arithmetic average (UPG- MA) showed that the bacterial communities of the sediment samples S1 and S2 in the above two culture systems were a cluster, the similarity of bacterial communities was 54.5%. The bacterial communities of seawater samples S3 and S4 in the above culture systems were in clusters, and the similarity of the bacterial communi- ties was 84.0%. The results showed that the microorganism ecological level in the Babylonia areolata culture systems of the pond mulched plastic film and sand in bottom could be similar to the sub-tidal zone culture systems through changing the pond seawater and monitoring the microbial population.
基金funded by National Natural Science Foundation Project (40801077)Ministry of Education Key Project (209100)+1 种基金Natural Science Foundation of Chongqing ( CSTC, 2008BB7367 )Chongqing Municipal Education Commission of Science and Technology Research Grant Project (KJ070811)~~
文摘The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored.
基金The National Natural Science Foundation of China under contract No. 41001271
文摘The coastal ecosystem health assessment is a field of increasing importance.In this paper,a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made,mainly based on remote sensing data and GIS technique.Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development.Firstly,human activities,hydrology and ecosystem problems in the study area were discussed and analyzed.Secondly,from 4 aspects of human stress,physical,chemical and biological responses to anthropogenic activities and natural stress,several indicators such as water transparency(Secchi Disk Depth,SDD),suspended substance concentration,dissolved inorganic nitrogen,active phosphate,chlorophyll,harmful algae bloom,as well as distribution of sewage,sea lanes and port were employed.Thirdly,the Analytic Hierarchical Process was used for indicator weight calculation,and the ecosystem health criteria were established according to the integrative analysis of national water quality criteria,similar coastal ecosystem health research in other places or data inherent properties.The results indicated that from 2005 to 2007 the coastal water ecosystem health value in Zhejiang Province was unhealthy and needs ecological restoration by human intervention.
基金supported by the National 973 Basic Research Program (Grant No.2006CB202308)the Major National Science & Technology Program (2008ZX05008-004-012)
文摘Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality (2-3 orders of magnitude at the intersection zone) and the formation mechanisms of the fault intersection zone. Differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized.
基金the"863"Marine Monitor of Hi-tech Research and Development Program of China under contract No.2003AA604040.
文摘China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic development and modern management.Laying a theoretical foundation for the modern management of China's costal zone is aimed at. This research focuses on the following processing and analyzing technologies for coastal zone high-resolution remote sensing data: organization and management of large amounts of high-resolution remote sensing data, quick and precise spatial positioning system,algorithms for image fusion in feature level and coastal zone feature extraction. They will form a technical foundation of the system. And, if combined with other research results such as coastal zone remote sensing classification system and its mapping subsystem, an advanced technical frame for remote sensing investigation of coastal zone resource will be constructed.
基金Project supported by the State Key Program for Basic Research of China (Grant No 2005CB724206)
文摘In this paper we use theoretical analysis and extensive simulations to study zone inhomogeneity with the random asymmetric simple exclusion process (ASEP). In the inhomogeneous zone, the hopping probability is less than 1. Two typical lattice geometries are investigated here. In case A, the lattice includes two equal segments. The hopping probability in the left segment is equal to 1, and in the right segment it is equal to p, which is less than 1. In case B, there are three equal segments in the system; the hopping probabilities in the left and right segments are equal to 1, and in the middle segment it is equal to p, which is less than 1. Through theoretical analysis, we can discover the effect on these systems when p is changed.
基金supported by grants from the National Natural Science Foundation of China (EF0410408 and CRR-0120778)
文摘Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in complex patterns. Here I describe some of our observations and experiments showing that mycorrhizal fungi play key roles in moving water for both transpiration and to facilitate nutrient acquisition under dry conditions. Mycorrhizal fungal hyphae grow from both surface and deep roots even into bedrock to help extract water under dry conditions. In both deep and surface roots, mycorrhizal fungi acquire water from pores too small for roots and root hairs to access, and at distances from roots and root hairs. Mycorrhizal fungi are also able to utilize hydraulic-lifted water from plants to obtain nutrients in extremely dry surface soils. The importance of these root symbionts in water and nutrient dynamics, and as integrators of surface and deeper water dynamics need further investigation.
基金the“863”Marine Monitor of Hitech Research and Development Program of China under contract No.,5 2003AA604040 a, 2002AA639640.
文摘To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management.
基金funded by the National Natural Science Foundation of China(Grants.41272222 to C.Z.Song and 41472166 to S.Lin)China Geological Survey(Grants.1212011121116 to S.Lin)a China Scholarship Council scholarship to H.Liu
文摘Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in the Tongbai-Dabie complexes. However, it cannot explain the most deformations in the shear zones. The northwest-southeast shear zones are developed around or wrapped the Tongbai-Dabie complexes. They play an important role for the interpretation of the tectonic evolution of the Tongbai-Dabie orogenic belt. By a systematically observation and description of the geometry and kinematics of these shear zones, we found that the shear zones to the north dip NE and have a uniform sinistral shear sense, the shear zone to the south dips SW and has a uniform dextral shear sense, and the shear zones at the core are sub-horizontal and have a uniform top-to-NW sense of shear. Combining with the comparison of previous and our geochronological studies, we interpret these associations as indicating that these shear zones were originally a single, more flat-lying and sub- horizontal shear zone with a uniform top-to-NW shear sense before the folding-doming of the Tongbai- Dabie complexes and suggest that the Tongbai-Dabie orogenic belt experienced a uniform top-to-NW orogen-paraUel extension in the ductile lithosphere before the widespread magmatism in the Cretaceous.
基金Supported by Independent Innovation Foundation of Shandong University of China(Grant No.2013GN007)
文摘The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the balance of number of kinds of items between different zones but not the number of items and the idle time in each zone. In this paper, an idle factor is proposed to measure the idle time exactly. The idle factor is proven to obey the same vary trend with the idle time, so the object of this problem can be simplified from minimizing idle time to minimizing idle factor. Based on this, the model of item assignment problem in synchronized zone automated order picking system is built. The model is a form of relaxation of parallel machine scheduling problem which had been proven to be NP-complete. To solve the model, a taboo search algorithm is proposed. The main idea of the algorithm is minimizing the greatest idle factor of zones with the 2-exchange algorithm. Finally, the simulation which applies the data collected from a tobacco distribution center is conducted to evaluate the performance of the algorithm. The result verifies the model and shows the algorithm can do a steady work to reduce idle time and the idle time can be reduced by 45.63% on average. This research proposed an approach to measure the idle time in synchronized zone automated order picking system. The approach can improve the picking efficiency significantly and can be seen as theoretical basis when optimizing the synchronized automated order picking systems.
基金financially supported by the National Geological Survey Project and National Scientific and Technological Support Project (Grant Nos. 1212011085534 and 2011BAB04B05)
文摘The Sanchahe quartz monzonite intrusion is situated in the middle segment of the North Qinling tectonic belt, Central China mainland, and consists chiefly of sanukitoid–like and granodioritic-monzogranitic rocks. The sanukitoid–like rocks are characterized by quartz monzonites, which display higher Mg#(55.0–59.0), and enrichments in Na2 O+K2 O(7.28–8.94 %), Ni(21-2312 ppm), Cr(56-4167 ppm), Sr(553-923 ppm), Ba(912-1355 ppm) and LREE((La/Yb)N =9.47–15.3), from negative to slightly positive Eu anomalies(δEu=+0.61 to +1.10), but also depletion in Nb, Ta and Ti. The granodioritic-monzogranitic rocks diaplay various Mg#of 6.00-53.0, high Na2 O+K2 O(7.20– 8.30%), Sr(455–1081 ppm) and(La/Yb)N(27.6–47.8), with positive Eu anomalies(δEu=1.03–1.57) and depleted Nb, Ta and Ti. Laser ablation inductively coupled plasma mass spectrometry(LA-ICPMS) zircon U-Pb isotopic dating reveals that the sanukitoid-like rocks were emplaced at two episodes of magmatism at 457±3 Ma and 431±2 Ma, respectively. The monzogranites were emplaced at 445±7Ma. Sanukitoid–like rocks have their εHf(t) values ranging from +0.3 to +15.1 with Hf–depleted mantle model ages of 445 to 1056 Ma, and the monzogranite shows its εHf(t) values ranging from 21.6 to +10.8 with Hf–depleted mantle model ages of 635 to 3183 Ma. Petrological, geochemical and zircon Lu –Hf isotopic features indicate that the magmatic precursor of sanukitoid–like rocks was derived from partial melting of the depleted mantle wedge materials that were metasomatized by fluids and melts related to subduction of oceanic slab, subsequently the sanukitoid magma ascended to crust level. This emplaced mantle magma caused partial melting of crustally metamorphosed sedimentary rocks, and mixing with the crustal magma, and suffered fractional crystallization, which lead to formations of quartz monzonites. However, the magmatic precursor of the granodioritic-monzogranitic rocks were derived from partial melting of subducted oceanic slab basalts. Integrated previous investigation for the adackitic rocks in the south of the intrusion, the Sanchahe intrusion signed that the North Qinling tectonic zone was developed in an early Paleozoic transitionally tectonic background from an island arc to back–arc.
基金Key Project in National Science & Technology Pillar Program,China(No.2007BAE41B04)
文摘Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.
文摘The aim of the current study was to gain a better understanding of the changes in soil microbial biomass and basal respiration dynamics in the vicinity of the bean caper (Zygophyllura duraosura) perennial desert shrub and the inter-shrub sites. Microbial biomasses as well as basal respiration were found to be significantly greater in the soil samples taken beneath the Z. duraosura shrubs than from the inter-shrub sampling sites, with no differences between the two sampling layers (0-10 and 10-20 cm) throughout the study period. However, seasonal changes were observed due to autumn dew formation, which significantly affected microbial biomass and basal respiration in the upper-layer inter-shrub locations. The calculated metabolic coefficient (qCO2) revealed significant differences between the two sampling sites as well as between the two soil layers, elucidating the abiotic effect between the sites throughout the study period. The substrate availability index was found to significantly demonstrate the differences between the two sites, elucidating the significant contribution of Z. duraosura in food source availability and in moderating harsh abiotic components. The importance of basal microbial parameters and the derived indices as tools demonstrated the importance and need for basic knowledge in understanding plant-soil interactions determined by an unpredictable and harsh desert environment.
文摘A systematic account of micro-textures and a few compositional profiles of plagioclase from high-alumina basaltic aa lava erupted during the year 1994-1995, from Barren Island Volcano, NE India ocean, are presented for the first time. The identified micro-textures can be grouped into two categories: (i) Growth related textures in the form of coarse/fine-sieve morphology, fine-scale oscillatory zoning and resorption surfaces resulted when the equilibrium at the crystal-melt interface was fluctuated due to change in temperature or H20 or pressure or composition of the crystallizing melt; and (ii) morphological texture, like glomerocryst, synneusis, swallow-tailed crystal, microlite and broken crystals, formed by the influence of dynamic behavior of the crystallizing magma (convection, turbulence, degassing, etc.). Each micro-texture has developed in a specific magmatic environment, accordingly, a first order magma plumbing model and crystallization dynamics are envisaged for the studied lava unit. Magma generated has undergone extensive fractional crystallization of An-rich plagioclase in stable magmatic environment at a deeper depth. Subsequently they ascend to a shallow chamber where the newly brought crystals and pre-existing crystals have undergone dynamic crystallization via dissolution-regrowth processes in a convective self- mixing environment. Such repeated recharge-recycling processes have produced various populations of plagioclase with different micro-textural stratigraphy in the studied lava unit. Intermittent degassing and eruption related decompression have also played a major role in the final stage of crystallization dynamics.