Efficient real time data exchange over the Internet plays a crucial role in the successful application of web-based systems. In this paper, a data transfer mechanism over the Internet is proposed for real time web bas...Efficient real time data exchange over the Internet plays a crucial role in the successful application of web-based systems. In this paper, a data transfer mechanism over the Internet is proposed for real time web based applications. The mechanism incorporates the eXtensible Markup Language (XML) and Hierarchical Data Format (HDF) to provide a flexible and efficient data format. Heterogeneous transfer data is classified into light and heavy data, which are stored using XML and HDF respectively; the HDF data format is then mapped to Java Document Object Model (JDOM) objects in XML in the Java environment. These JDOM data objects are sent across computer networks with the support of the Java Remote Method Invocation (RMI) data transfer infrastructure. Client's defined data priority levels are implemented in RMI, which guides a server to transfer data objects at different priorities. A remote monitoring system for an industrial reactor process simulator is used as a case study to illustrate the proposed data transfer mechanism.展开更多
The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering...The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering fertilizer is still unclear. In this study, the early rice cultivar Zhongjiazao 17 and late rice cultivar H You 518 were used as materials, and the effects of different application times of tillering fertilizer on yield and population development of double-cropping rice transplanted by machine were investigated. The tillering fertilizer was applied 7(D07), 10(D10) and 13(D13) d after the transplanting, respectively. The results showed that compared with those in the D07 treatment groups, the yield of early rice in the D10 and D13 treatment groups were reduced by 9.4% and 3.8%, respectively, and the yield of late rice in the D10 and D13 treatment groups were reduced by 4.5% and 12.6%,respectively. However, there were no significant differences in rice yield among the treatment groups. The application time of tillering fertilizer showed significant effects on grain number per panicle and seed setting rate of early rice. The grain number per panicle in the D10 treatment group was significantly lower than that in the D07 treatment group, and the seed setting rate of the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). For the late rice, the effect of application time of tillering fertilizer on effective tiller number was most obvious, and the effective tiller number in the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). Compared with those in the D07 treatment group, the effective tiller numbers, leaf area indexes and biomasses in the D10 and D13 treatment groups were all trended to be decreased. Therefore,to improve the quality of population and fulfill the high-yielding potential of double-cropping rice transplanted by machine, the tillering fertilizer should be applied as early as possible after rice seedlings turn green.展开更多
In recent times,real time wireless networks have found their applicability in several practical applications such as smart city,healthcare,surveillance,environmental monitoring,etc.At the same time,proper localization...In recent times,real time wireless networks have found their applicability in several practical applications such as smart city,healthcare,surveillance,environmental monitoring,etc.At the same time,proper localization of nodes in real time wireless networks helps to improve the overall functioning of networks.This study presents an Improved Metaheuristics based Energy Efficient Clustering with Node Localization(IM-EECNL)approach for real-time wireless networks.The proposed IM-EECNL technique involves two major processes namely node localization and clustering.Firstly,Chaotic Water Strider Algorithm based Node Localization(CWSANL)technique to determine the unknown position of the nodes.Secondly,an Oppositional Archimedes Optimization Algorithm based Clustering(OAOAC)technique is applied to accomplish energy efficiency in the network.Besides,the OAOAC technique derives afitness function comprising residual energy,distance to cluster heads(CHs),distance to base station(BS),and load.The performance validation of the IM-EECNL technique is carried out under several aspects such as localization and energy efficiency.A wide ranging comparative outcomes analysis highlighted the improved performance of the IM-EECNL approach on the recent approaches with the maximum packet delivery ratio(PDR)of 0.985.展开更多
Wireless Sensor Networks(WSNs)are a major element of Internet of Things(IoT)networks which offer seamless sensing and wireless connectivity.Disaster management in smart cities can be considered as a safety critical ap...Wireless Sensor Networks(WSNs)are a major element of Internet of Things(IoT)networks which offer seamless sensing and wireless connectivity.Disaster management in smart cities can be considered as a safety critical application.Therefore,it becomes essential in ensuring network accessibility by improving the lifetime of IoT assisted WSN.Clustering and multihop routing are considered beneficial solutions to accomplish energy efficiency in IoT networks.This article designs an IoT enabled energy aware metaheuristic clustering with routing protocol for real time disaster management(EAMCR-RTDM).The proposed EAMCR-RTDM technique mainly intends to manage the energy utilization of nodes with the consideration of the features of the disaster region.To achieve this,EAMCR-RTDM technique primarily designs a yellow saddle goatfish based clustering(YSGF-C)technique to elect cluster heads(CHs)and organize clusters.In addition,enhanced cockroach swarm optimization(ECSO)based multihop routing(ECSO-MHR)approach was derived for optimal route selection.The YSGF-C and ECSO-MHR techniques compute fitness functions using different input variables for achieving improved energy efficiency and network lifetime.The design of YSGF-C and ECSO-MHR techniques for disaster management in IoT networks shows the novelty of the work.For examining the improved outcomes of the EAMCR-RTDM system,a wide range of simulations were performed and the extensive results are assessed in terms of different measures.The comparative outcomes highlighted the enhanced outcomes of the EAMCRRTDM algorithm over the existing approaches.展开更多
A pot experiment was conducted to study the effects of different nitrogen application time (during the tillering or the booting stages) with the same nitrogen rates on the caryopsis development and grain quality of ...A pot experiment was conducted to study the effects of different nitrogen application time (during the tillering or the booting stages) with the same nitrogen rates on the caryopsis development and grain quality of rice variety Yangdao 6. The increased nitrogen fertilizer (urea), especially applied during the booting stage, could evidently increase the milled rice rate, head rice rate and protein content in rice grains compared with the control (no nitrogen application), and decrease chalky grain rate and amylose content. Moreover, the increased nitrogen fertilizer significantly affected the caryopsis development and enhanced the grain weight when nitrogen applied during the tillering and the booting stages, especially during the booting stage. During caryopsis development the increased nitrogen fertilizer applied during the tillering and booting stages could obviously decrease the total starch and amylose contents, but not obviously for the amylopectin content in rice grain. Increased topdressing of nitrogen fertilizer, especially applied during the booting stage, had significant effect on the development and structures of amyloplasts and proteinoplasts. That is, it could change the distribution, number and shape of amyloplasts and proteinoplasts in the endosperm cells especially in grain abdomen, Compared with the control the arrangements of amyloplasts and proteinoplasts were closer, with more numbers, higher density and less interspaces each ohter. Furthermore, most amyloplasts showed polyhedron under the increased nitrogen fertilizer level.展开更多
Terahertz (THz) radiation, whose frequency ranges from 0.1 THz to 10.0 THz, has rich science, but limited technology. It has long been considered the last remaining scientific gap in the electromagnetic spectrum. Fa...Terahertz (THz) radiation, whose frequency ranges from 0.1 THz to 10.0 THz, has rich science, but limited technology. It has long been considered the last remaining scientific gap in the electromagnetic spectrum. Far from being fully exploited, it offers great opportunities in science, innovation, new technology, and potential applications. THz science and technology enables fundamental research directly impact our lives, from industrial quality control,展开更多
[Objective] The aim was to provide a scientific and rational water,nitrogen model for achieving high yield,high quality of wheat and water and fertilizer saving.[Method] Under the field conditions,the effects of irrig...[Objective] The aim was to provide a scientific and rational water,nitrogen model for achieving high yield,high quality of wheat and water and fertilizer saving.[Method] Under the field conditions,the effects of irrigation frequencies and N application times on net photosynthetic rate(Pn),chlorophyll fluorescence parameters of flag leaf and yield of wheat was studied.[Result] The differences on Pn,chlorophyll fluorescence parameters Fv/Fo,Fv/Fm,qP,qN of flag leaves and yield of wheat among different irrigation times had reached a significant level,and the difference between treatment without irrigation and irrigation treatments were relatively large;the difference on Pn,Fv/Fo,Fv/Fm,qP and qN between treatments of basal application of N fertilizer and N application(40%)in returning green stage was not significant,however,the photosynthetic parameters and yield of two treatments were obviously lower than that of N application(40%)in jointing stage or booting stage.[Conclusion] The effects of irrigation frequencies and N application times showed significant interaction effects on photosynthetic characteristics of wheat flag leaves and yield,in which W2N4 treatment combination was best.展开更多
The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are un...The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are unified into a single one,which is compressed by the extended coding technique.A reconfigurable scan test application mechanism is presented,in which test data for multiple cores are scanned and captured jointly to make SoC test application more efficient with low hardware overhead added.The proposed union test technique is applied to an academic SoC embedded by six large ISCAS'89 benchmarks,and to an ITC' 02 benchmark circuit.Experiment results show that compared with the existing schemes in which a core test set is compressed and applied independently of other cores,the proposed scheme can not only improve test data compression/decompression,but also reduce the redundant shift and capture cycles during scan testing,decreasing SoC test application time effectively.展开更多
Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^+-tree are shown to outperform conventional main memory indic...Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^+-tree are shown to outperform conventional main memory indices such as the AVL-tree and the T-tree. This paper proposes a cacheconscious version of the T-tree, CST-tree, defined according to the cache-conscious definition. To separate the keys within a node into two parts, the CST-tree can gain higher cache hit ratio.展开更多
The stability in L∞-norm is considered for the Ritz-Volterra projection and some applications are presented in this paper. As a result, point-wise error estimates are established for the finite element approximation ...The stability in L∞-norm is considered for the Ritz-Volterra projection and some applications are presented in this paper. As a result, point-wise error estimates are established for the finite element approximation for the parabolic integrodifferential equation, Sobolev equations, and a diffusion equation with non-local boundary value problem.展开更多
The time delay estimation (TDE) of two different received signals from the same source has attracted many interests of researchers in the field of signal processing. A method described for precisely estimating time de...The time delay estimation (TDE) of two different received signals from the same source has attracted many interests of researchers in the field of signal processing. A method described for precisely estimating time delay in this paper is based on the assumption that little priori knowledge on statistical characteristics is available for the received signals. The variance of the estimate is derived . The basic architecture of this method is to use the adaptive noise canceller, in the steady state , and to interpolate the weight coefficients by using a generalized quadratic interpolation matrix. The formula of the time delay estimation is presented . The method proposed by F.A. Reed is a special case of this method . The hardware implementation is much easier than that of the conventional time delay estimation method . The results of the system simulation and the experimental results at sea show a good agreement with the theoretical analysis.展开更多
By generalizing the concept of mean in mathematical statistics to a mean generation function(MGF), the extended matrix of MGF is defined and then a new model of time series is presented.A calculatingseheme for modelli...By generalizing the concept of mean in mathematical statistics to a mean generation function(MGF), the extended matrix of MGF is defined and then a new model of time series is presented.A calculatingseheme for modelling of monovariate time series is deduced cooperating with a normalization procedure of vector and a couple score criterion.An example of climatic prediction for ten-year scale is given in this paper,the tendency of variation for every year can be predicted skillfully with the model.展开更多
This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free...This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free-floating space robot because the base disturbance minimization will result in less energy consumption and prolonged control application. The analytical formulation of the reaction torque is derived in this article, and the reaction torque control can achieve reactionless control and satellite base disturbance minimization. Furthermore, we derive the reaction torque based control of the space robot for base disturbance minimization from both the non-strict task priority and strict task priority control strategy. The dynamics singularity in the proposed algorithm is avoided in this paper. Besides, a real time simulation system of the space robot under Linux/real time application interface(RTAI) is developed to verify and test the feasibility and reliability of the method. The experimental results demonstrate the feasibility of online reaction torque control of the redundant free-floating space robot.展开更多
Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. A...Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. As the greatest consumers of N fertilizer in the world, Chinese farmers have overused N, and there has been poor synchrony between crop N demand and N supply because of limited understanding of the N uptake-yield relationship. To address this problem, this study evaluated the total and dynamic N requirement for different yield ranges of two major crops (maize and wheat), and suggested improvements to N management strategies. Whole-plant N aboveground uptake requirement per grain yield (Nreq) initially deceased with grain yield improvement and then stagnated, and yet most farmers still believed that more fertilizer and higher grain yield were synonymous. When maize yield increased from 〈 7.5 to 〉 12.0 Mg ha-I, Nreq decreased from 19.8 to 17.0 kg Mg-1 grain. For wheat, it decreased from 27.1 kg Mg-1 grain for grain yield 〈 4.5 Mg ha-1 to 22.7 kg Mg-1 grain for yield 〉 9.0 Mg ha-1. Meanwhile, the percentage of dry matter and N accumulation in the middle-late growing season increased significantly with grain yield, which indicated that N fertilization should be concentrated in the middle-late stage to match crop demand while farmers often applied the majority of N fertilizer either before sowing or during early growth stages. We accordingly developed an integrated soil-crop system management strategy that simultaneously increases both grain yield and NUE.展开更多
文摘Efficient real time data exchange over the Internet plays a crucial role in the successful application of web-based systems. In this paper, a data transfer mechanism over the Internet is proposed for real time web based applications. The mechanism incorporates the eXtensible Markup Language (XML) and Hierarchical Data Format (HDF) to provide a flexible and efficient data format. Heterogeneous transfer data is classified into light and heavy data, which are stored using XML and HDF respectively; the HDF data format is then mapped to Java Document Object Model (JDOM) objects in XML in the Java environment. These JDOM data objects are sent across computer networks with the support of the Java Remote Method Invocation (RMI) data transfer infrastructure. Client's defined data priority levels are implemented in RMI, which guides a server to transfer data objects at different priorities. A remote monitoring system for an industrial reactor process simulator is used as a case study to illustrate the proposed data transfer mechanism.
基金Supported by Key Project of the National Twelfth-Five Year Research Program of China(2011BAD16B04)"Gan-Po Talent 555"Project of Jiangxi Province[GCZ2012(1)]+2 种基金National Transformation Fund for Agricultural Science and Technology Achievements(2013GB2C500244)Science and Technology Plan of Action for Universities and Colleges in Jiangxi Province(12003)Special Fund for Agro-Scientific Research in the Public Interest(201303102)~~
文摘The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering fertilizer is still unclear. In this study, the early rice cultivar Zhongjiazao 17 and late rice cultivar H You 518 were used as materials, and the effects of different application times of tillering fertilizer on yield and population development of double-cropping rice transplanted by machine were investigated. The tillering fertilizer was applied 7(D07), 10(D10) and 13(D13) d after the transplanting, respectively. The results showed that compared with those in the D07 treatment groups, the yield of early rice in the D10 and D13 treatment groups were reduced by 9.4% and 3.8%, respectively, and the yield of late rice in the D10 and D13 treatment groups were reduced by 4.5% and 12.6%,respectively. However, there were no significant differences in rice yield among the treatment groups. The application time of tillering fertilizer showed significant effects on grain number per panicle and seed setting rate of early rice. The grain number per panicle in the D10 treatment group was significantly lower than that in the D07 treatment group, and the seed setting rate of the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). For the late rice, the effect of application time of tillering fertilizer on effective tiller number was most obvious, and the effective tiller number in the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). Compared with those in the D07 treatment group, the effective tiller numbers, leaf area indexes and biomasses in the D10 and D13 treatment groups were all trended to be decreased. Therefore,to improve the quality of population and fulfill the high-yielding potential of double-cropping rice transplanted by machine, the tillering fertilizer should be applied as early as possible after rice seedlings turn green.
基金supported by Ulsan Metropolitan City-ETRI joint cooperation project[21AS1600,Development of intelligent technology for key industriesautonomous human-mobile-space autonomous collaboration intelligence technology].
文摘In recent times,real time wireless networks have found their applicability in several practical applications such as smart city,healthcare,surveillance,environmental monitoring,etc.At the same time,proper localization of nodes in real time wireless networks helps to improve the overall functioning of networks.This study presents an Improved Metaheuristics based Energy Efficient Clustering with Node Localization(IM-EECNL)approach for real-time wireless networks.The proposed IM-EECNL technique involves two major processes namely node localization and clustering.Firstly,Chaotic Water Strider Algorithm based Node Localization(CWSANL)technique to determine the unknown position of the nodes.Secondly,an Oppositional Archimedes Optimization Algorithm based Clustering(OAOAC)technique is applied to accomplish energy efficiency in the network.Besides,the OAOAC technique derives afitness function comprising residual energy,distance to cluster heads(CHs),distance to base station(BS),and load.The performance validation of the IM-EECNL technique is carried out under several aspects such as localization and energy efficiency.A wide ranging comparative outcomes analysis highlighted the improved performance of the IM-EECNL approach on the recent approaches with the maximum packet delivery ratio(PDR)of 0.985.
基金This research has been funded by Dirección General de Investigaciones of Universidad Santiago de Cali under call No.01–2021.
文摘Wireless Sensor Networks(WSNs)are a major element of Internet of Things(IoT)networks which offer seamless sensing and wireless connectivity.Disaster management in smart cities can be considered as a safety critical application.Therefore,it becomes essential in ensuring network accessibility by improving the lifetime of IoT assisted WSN.Clustering and multihop routing are considered beneficial solutions to accomplish energy efficiency in IoT networks.This article designs an IoT enabled energy aware metaheuristic clustering with routing protocol for real time disaster management(EAMCR-RTDM).The proposed EAMCR-RTDM technique mainly intends to manage the energy utilization of nodes with the consideration of the features of the disaster region.To achieve this,EAMCR-RTDM technique primarily designs a yellow saddle goatfish based clustering(YSGF-C)technique to elect cluster heads(CHs)and organize clusters.In addition,enhanced cockroach swarm optimization(ECSO)based multihop routing(ECSO-MHR)approach was derived for optimal route selection.The YSGF-C and ECSO-MHR techniques compute fitness functions using different input variables for achieving improved energy efficiency and network lifetime.The design of YSGF-C and ECSO-MHR techniques for disaster management in IoT networks shows the novelty of the work.For examining the improved outcomes of the EAMCR-RTDM system,a wide range of simulations were performed and the extensive results are assessed in terms of different measures.The comparative outcomes highlighted the enhanced outcomes of the EAMCRRTDM algorithm over the existing approaches.
基金This work was supported by the National Natural Science Foundation of China(Grant No.30070454).
文摘A pot experiment was conducted to study the effects of different nitrogen application time (during the tillering or the booting stages) with the same nitrogen rates on the caryopsis development and grain quality of rice variety Yangdao 6. The increased nitrogen fertilizer (urea), especially applied during the booting stage, could evidently increase the milled rice rate, head rice rate and protein content in rice grains compared with the control (no nitrogen application), and decrease chalky grain rate and amylose content. Moreover, the increased nitrogen fertilizer significantly affected the caryopsis development and enhanced the grain weight when nitrogen applied during the tillering and the booting stages, especially during the booting stage. During caryopsis development the increased nitrogen fertilizer applied during the tillering and booting stages could obviously decrease the total starch and amylose contents, but not obviously for the amylopectin content in rice grain. Increased topdressing of nitrogen fertilizer, especially applied during the booting stage, had significant effect on the development and structures of amyloplasts and proteinoplasts. That is, it could change the distribution, number and shape of amyloplasts and proteinoplasts in the endosperm cells especially in grain abdomen, Compared with the control the arrangements of amyloplasts and proteinoplasts were closer, with more numbers, higher density and less interspaces each ohter. Furthermore, most amyloplasts showed polyhedron under the increased nitrogen fertilizer level.
文摘Terahertz (THz) radiation, whose frequency ranges from 0.1 THz to 10.0 THz, has rich science, but limited technology. It has long been considered the last remaining scientific gap in the electromagnetic spectrum. Far from being fully exploited, it offers great opportunities in science, innovation, new technology, and potential applications. THz science and technology enables fundamental research directly impact our lives, from industrial quality control,
基金Supported by National Key Basic Research Program(NKBRP)(G2000077900)Key Scientific and Technological Project of Henan Province(122012300)~~
文摘[Objective] The aim was to provide a scientific and rational water,nitrogen model for achieving high yield,high quality of wheat and water and fertilizer saving.[Method] Under the field conditions,the effects of irrigation frequencies and N application times on net photosynthetic rate(Pn),chlorophyll fluorescence parameters of flag leaf and yield of wheat was studied.[Result] The differences on Pn,chlorophyll fluorescence parameters Fv/Fo,Fv/Fm,qP,qN of flag leaves and yield of wheat among different irrigation times had reached a significant level,and the difference between treatment without irrigation and irrigation treatments were relatively large;the difference on Pn,Fv/Fo,Fv/Fm,qP and qN between treatments of basal application of N fertilizer and N application(40%)in returning green stage was not significant,however,the photosynthetic parameters and yield of two treatments were obviously lower than that of N application(40%)in jointing stage or booting stage.[Conclusion] The effects of irrigation frequencies and N application times showed significant interaction effects on photosynthetic characteristics of wheat flag leaves and yield,in which W2N4 treatment combination was best.
基金Supported by the National Natural Science Fund of China (No.60876028)the key Project of Natural Science Foundation of the Anhui Higher Education Institutions (No.KJ2010A280)
文摘The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are unified into a single one,which is compressed by the extended coding technique.A reconfigurable scan test application mechanism is presented,in which test data for multiple cores are scanned and captured jointly to make SoC test application more efficient with low hardware overhead added.The proposed union test technique is applied to an academic SoC embedded by six large ISCAS'89 benchmarks,and to an ITC' 02 benchmark circuit.Experiment results show that compared with the existing schemes in which a core test set is compressed and applied independently of other cores,the proposed scheme can not only improve test data compression/decompression,but also reduce the redundant shift and capture cycles during scan testing,decreasing SoC test application time effectively.
基金Supported bythe National High Technology of 863Project (2002AA1Z2308 ,2002AA118030)
文摘Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^+-tree are shown to outperform conventional main memory indices such as the AVL-tree and the T-tree. This paper proposes a cacheconscious version of the T-tree, CST-tree, defined according to the cache-conscious definition. To separate the keys within a node into two parts, the CST-tree can gain higher cache hit ratio.
文摘The stability in L∞-norm is considered for the Ritz-Volterra projection and some applications are presented in this paper. As a result, point-wise error estimates are established for the finite element approximation for the parabolic integrodifferential equation, Sobolev equations, and a diffusion equation with non-local boundary value problem.
文摘The time delay estimation (TDE) of two different received signals from the same source has attracted many interests of researchers in the field of signal processing. A method described for precisely estimating time delay in this paper is based on the assumption that little priori knowledge on statistical characteristics is available for the received signals. The variance of the estimate is derived . The basic architecture of this method is to use the adaptive noise canceller, in the steady state , and to interpolate the weight coefficients by using a generalized quadratic interpolation matrix. The formula of the time delay estimation is presented . The method proposed by F.A. Reed is a special case of this method . The hardware implementation is much easier than that of the conventional time delay estimation method . The results of the system simulation and the experimental results at sea show a good agreement with the theoretical analysis.
文摘By generalizing the concept of mean in mathematical statistics to a mean generation function(MGF), the extended matrix of MGF is defined and then a new model of time series is presented.A calculatingseheme for modelling of monovariate time series is deduced cooperating with a normalization procedure of vector and a couple score criterion.An example of climatic prediction for ten-year scale is given in this paper,the tendency of variation for every year can be predicted skillfully with the model.
基金supported by National Basic Research Program of China(973 Program)(No.2013CB733103)Program for New Century Excellent Talents in University(No.NCET-10-0058)
文摘This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free-floating space robot because the base disturbance minimization will result in less energy consumption and prolonged control application. The analytical formulation of the reaction torque is derived in this article, and the reaction torque control can achieve reactionless control and satellite base disturbance minimization. Furthermore, we derive the reaction torque based control of the space robot for base disturbance minimization from both the non-strict task priority and strict task priority control strategy. The dynamics singularity in the proposed algorithm is avoided in this paper. Besides, a real time simulation system of the space robot under Linux/real time application interface(RTAI) is developed to verify and test the feasibility and reliability of the method. The experimental results demonstrate the feasibility of online reaction torque control of the redundant free-floating space robot.
基金supported by the National Basic Research Program(973 Program) of China(No.2015CB150402)the National Maize Production System in China(No.CARS-02-24)+1 种基金the Special Fund for Agroscientific Research in the Public Interest of China (No.201103003)the Innovative Group Grant of the NSFC,China(No.31421092)
文摘Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. As the greatest consumers of N fertilizer in the world, Chinese farmers have overused N, and there has been poor synchrony between crop N demand and N supply because of limited understanding of the N uptake-yield relationship. To address this problem, this study evaluated the total and dynamic N requirement for different yield ranges of two major crops (maize and wheat), and suggested improvements to N management strategies. Whole-plant N aboveground uptake requirement per grain yield (Nreq) initially deceased with grain yield improvement and then stagnated, and yet most farmers still believed that more fertilizer and higher grain yield were synonymous. When maize yield increased from 〈 7.5 to 〉 12.0 Mg ha-I, Nreq decreased from 19.8 to 17.0 kg Mg-1 grain. For wheat, it decreased from 27.1 kg Mg-1 grain for grain yield 〈 4.5 Mg ha-1 to 22.7 kg Mg-1 grain for yield 〉 9.0 Mg ha-1. Meanwhile, the percentage of dry matter and N accumulation in the middle-late growing season increased significantly with grain yield, which indicated that N fertilization should be concentrated in the middle-late stage to match crop demand while farmers often applied the majority of N fertilizer either before sowing or during early growth stages. We accordingly developed an integrated soil-crop system management strategy that simultaneously increases both grain yield and NUE.