We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single ...We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.展开更多
A geothermal resource can be defined as a reservoir inside the Earth from which heat can be extracted economically Geothermal resources are classified on the basis of different aspects, such as heat source, heat trans...A geothermal resource can be defined as a reservoir inside the Earth from which heat can be extracted economically Geothermal resources are classified on the basis of different aspects, such as heat source, heat transfer, reservoir tem perature, physical state, commercial utilization and geological settings. Unfortunately most of the current classifications that are used for geothermal systems are not complete. So, a combinational terminology of geological and tempera ture-based classifications would be more complete. This terminology can explain all geological situations, temperature and physical state of geothermal reservoir altogether. According to geological settings, in combinational terminology (from left to right), the class of geothermal resource’s name would be placed at first, then the physical state of reservoir (Liquid-dominated or Two-phase or Vapor-dominated) would be written and finally the class of the geothermal reser voir which is related to its temperature, is written.展开更多
Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common proced...Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common procedure that provides a clear and continuous passage between the conventional distinction of either a strictly classical or a strictly quantized state. While path integration, among other procedures, provides an alternative route to connect classical and quantum expressions, it normally involves complicated, model-dependent, integrations. Our alternative procedures involve only model-independent procedures, and use more natural and straightforward integrations that are universal in kind. To introduce the basic procedures our presentation begins with familiar methods that are limited to basic, conventional, canonical quantum mechanical examples. In the final sections we illustrate how alternative quantization procedures, e.g., spin and affine quantizations, can also have smooth paths between classical and quantum stories, and with a few brief remarks, can also lead to similar stories for non-renormalizable covariant scalar fields as well as quantum gravity.展开更多
Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization (DCCS) of eight n-dimensi...Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization (DCCS) of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the MATLAB simula- tion outcomes. We obtain the same results of numerical treatment of our synchronization using simulation observations of our example.展开更多
Current treatments for advanced hepatocellular carcinoma(HCC)have limited success in improving patients’quality of life and prolonging life expectancy.The clinical need for more efficient and safe therapies has contr...Current treatments for advanced hepatocellular carcinoma(HCC)have limited success in improving patients’quality of life and prolonging life expectancy.The clinical need for more efficient and safe therapies has contributed to the exploration of emerging strategies.Recently,there has been increased interest in oncolytic viruses(OVs)as a therapeutic modality for HCC.OVs undergo selective replication in cancerous tissues and kill tumor cells.Strikingly,pexastimogene devacirepvec(Pexa-Vec)was granted an orphan drug status in HCC by the U.S.Food and Drug Administration(FDA)in 2013.Meanwhile,dozens of OVs are being tested in HCC-directed clinical and preclinical trials.In this review,the pathogenesis and current therapies of HCC are outlined.Next,we summarize multiple OVs as single therapeutic agents for the treatment of HCC,which have demonstrated certain efficacy and lowtoxicity.Emerging carrier cell-,bioengineered cell mimetic-or nonbiological vehicle-mediated OV intravenous delivery systems in HCC therapy are described.In addition,we highlight the combination treatments between oncolytic virotherapy and other modalities.Finally,the clinical challenges and prospects of OV-based biotherapy are discussed,with the aim of continuing to develop a fascinating approach in HCC patients.展开更多
Sorafenib,a molecular targeted multi-kinase inhibitor,has received considerable interests in recent years due to its significant profiles of efficacy in cancer therapy.However,poor pharmacokinetic properties such as l...Sorafenib,a molecular targeted multi-kinase inhibitor,has received considerable interests in recent years due to its significant profiles of efficacy in cancer therapy.However,poor pharmacokinetic properties such as limited water solubility,rapid elimination and metabolism lead to low bioavailability,restricting its further clinical application.Over the past decade,with substantial progress achieved in the development of nanotechnology,various types of smart sorafenib nanoformulations have been developed to improve the targetability as well as the bioavailability of sorafenib.In this review,we summarize various aspects from the preparation and characterization to the evaluation of antitumor efficacy of numerous stimuli-responsive sorafenib nanodelivery systems,particularly with emphasis on their mechanism of drug release and tumor microenvironment response.In addition,this review makes great effort to summarize the nanosystem-based combination therapy of sorafenib with other antitumor agents,which can provide detailed information for further synergistic cancer therapy.In the final section of this review,we also provide a detailed discussion of future challenges and prospects of designing and developing ideal sorafenib nanoformulations for clinical cancer therapy.展开更多
A novel combined model of the vibration control for the coupled flexiblesystem and its general mathematic description are developed. In presented model, active and passivecontrols as well as force and moment controls ...A novel combined model of the vibration control for the coupled flexiblesystem and its general mathematic description are developed. In presented model, active and passivecontrols as well as force and moment controls are combined into a single unit to achieve theefficient vibration control of the flexible structures by multi-approaches. Considering thecomplexity of the energy transmission in the vibrating system, the transmission channels of thepower flow transmitted into the foundation are discussed, and the general forces and thecorresponding velocities are combined into a single function, respectively. Under the controlstrategy of the minimum power flow, the transmission characteristics of the power flow areinvestigated. From the presented numerical examples, it is obvious that the analytical model iseffective, and both force and moment controls are able to depress vibration energy substantially.展开更多
Aiming at the problems of large energy consumption and serious pollution of winter heating existing in the rural buildings in Southern Xinjiang,a combined active-passive heating system was proposed,and the simulation ...Aiming at the problems of large energy consumption and serious pollution of winter heating existing in the rural buildings in Southern Xinjiang,a combined active-passive heating system was proposed,and the simulation software was used to optimize the parameters of the system,according to the parameters obtained from the optimization,a test platform was built and winter heating test was carried out.The simulation results showed that the thickness of the air layer of 75 mm,the total area of the vent holes of 0.24 m^(2),and the thickness of the insulation layer of 120 mm were the optimal construction for the passive part;solar collector area of 28 m^(2),hot water storage tank volume of 1.4 m^(3),mass flow rate of 800 kg/h on the collector side,mass flow rate of 400 kg/h on the heat exchanger side,and output power of auxiliary heat source of 5∼9 kWwere the optimal constructions for active heating system.Test results showed that during the heating period,the system could provide sufficient heat to the room under different heating modes,and the indoor temperature reached over 18°C,which met the heating demand.The economic and environmental benefits of the system were analyzed,and the economic benefits of the systemwere better than coal-fired heating,and the CO_(2) emissionswere reduced by 3,292.25 kg compared with coalfiredheating.The results of the study showed that the combinedactive-passiveheating systemcouldeffectively solve the heating problems existing in rural buildings in Southern Xinjiang,and it also laid the theoretical foundation for the popularization of the combined heating systems.展开更多
The combined gradient representations for generalized Birkhoffian systems in event space are studied.Firstly,the definitions of six kinds of combined gradient systems and corresponding differential equations are given...The combined gradient representations for generalized Birkhoffian systems in event space are studied.Firstly,the definitions of six kinds of combined gradient systems and corresponding differential equations are given.Secondly,the conditions under which generalized Birkhoffian systems become combined gradient systems are obtained. Finally,the characteristics of combined gradient systems are used to study the stability of generalized Birkhoffian systems in event space. Seven examples are given to illustrate the results.展开更多
The aging development in Shanghai shows speed, high degree of aging, the number of elderly people living alone increased and other trends, the contradiction between degree of aging and care become more prominent. Howe...The aging development in Shanghai shows speed, high degree of aging, the number of elderly people living alone increased and other trends, the contradiction between degree of aging and care become more prominent. However, the prevalence of current pension model has a pension without medical care, health care and pension separate and other issues, so the development of "medical support combined with pension" long-term care insurance system is imperative. Based on the study to explore parts of the country which operate basic pension model of"medical pension combination", we analyze the necessity and feasibility of the implementation of Shanghai "medical support combined with pension " long-term care insurance system, by summing up experiences and lessons, put forward some of the recommendations for the development in Shanghai "medical support combined with pension" type of long-term care system.展开更多
The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform ...The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform (TIP) combined with other systems, such as Floating Production Storage and Offloading (FPSO) system, Floating Production Unit (FPU) system, Tender Assisted Drilling (TAD) system, etc., has drawn the industry attention and increased significantly in the past few years. For the areas lacking of pipeline system, the use of TIP(s) combined with FPSO has been chosen to efficiently develop the deepwater fields. The TIP with a Tender Assisted Drilling system significantly reduces the payload of the platform and reduces the investment in the TIP system substantially. This opens the door for many new deepwater field developments to use the tension leg platform. The advantage of the TIP combined with a TAD system is more significant when several TIPs are used for the continuous development of the field. One of the applications for the TIP with a tender assisted drilling system can be in the development of an offshore marginal field. Owing to the increase of water depth, the conventional fixed platform model for the exploration of those fields becomes uneconomical. It also would be too expensive to use a large TIP structure for those marginal fields due to the large amount of initial investment. The TIP system with tender assisted drilling can be used to develop those fields economically. There are many marginal fields in China offshore, especially in shelf areas. The application of this field developing model, combined with the existing field developing experience in China, will open the door for many marginal field developments. This paper will review the application of the combined TIP system through some examples of completed/ongoing projects, and major technical issues encountered in those practices. The potential application of this technology in China deepwater development will be discussed in the end.展开更多
Due to the mining,smelting,sewage irriga-tion,agricultural runoff,and development ofrural enterprises,combined pollution of Cd andZn in soil-rice systems has frequently oc-curred.This problem was studied by using thep...Due to the mining,smelting,sewage irriga-tion,agricultural runoff,and development ofrural enterprises,combined pollution of Cd andZn in soil-rice systems has frequently oc-curred.This problem was studied by using thepot-culture imitative method combined withhemical analysis and mathematical models.展开更多
This paper deals with knowledge representation of ESEP (Expert System for Earthqauke Prediction). Attending the characteristics of the knowledge in earthquake prediction domain, production representation and procedura...This paper deals with knowledge representation of ESEP (Expert System for Earthqauke Prediction). Attending the characteristics of the knowledge in earthquake prediction domain, production representation and procedural representation are connected in the knowledge repesentation model of ESEP named ESEP/K, and three new ways of evidence conbination are proposed for production rules besides 'AND' and 'OR'.展开更多
In this paper, a class of real-time parallel combined methods (RTPCM) of the digital simulation for a partitioned large system is presented. By means of combination of the parallelism across the system with the parall...In this paper, a class of real-time parallel combined methods (RTPCM) of the digital simulation for a partitioned large system is presented. By means of combination of the parallelism across the system with the parallelism across the method, stiff and non-stiff subsystems are solved in parallel on parallel computer by a parallel Rosenbrock method and a parallel RK method, respectively. Their construction, convergence and numerical stability are discussed, and the digitalsimulation experiments are conducted.展开更多
Resources are the base and core of education information, but current web education resources have no structure and it is still difficult to reuse them and make them can be self assembled and developed continually. Ac...Resources are the base and core of education information, but current web education resources have no structure and it is still difficult to reuse them and make them can be self assembled and developed continually. According to the knowledge structure of course and text, the relation among knowledge points, knowledge units from three levels of media material, we can build education resource components, and build TKCM (Teaching Knowledge Combination Model) based on resource components. Builders can build and assemble knowledge system structure and make knowledge units can be self assembled, thus we can develop and consummate them continually. Users can make knowledge units can be self assembled and renewed, and build education knowledge system to satisfy users' demand under the form of education knowledge system.展开更多
This paper addresses the design of practical communication strategies for multi-antenna amplify-and-forward and decode-and-forward relay systems. We show that simple linear techniques at the source and destination in ...This paper addresses the design of practical communication strategies for multi-antenna amplify-and-forward and decode-and-forward relay systems. We show that simple linear techniques at the source and destination in conjunction with maximum ratio combining can provide an optimal transmission strategy in terms of received SNR without imposing a huge computational load over the relay node(s). Besides, the structures of precoding matrices are very similar at the source and relay nodes, which reduces the complexity as all nodes can play the role of source and relay nodes without changing their transmission structure. Numerical results show that the proposed transmission and reception techniques can improve the received SNR, and hence enhance the ergodic capacity.展开更多
This paper presents a modification of an existing cognitive antenna design which contains two antennas: one is a sensing that covers the band from 1 - 11 GHz and the other is a hybrid triangular reconfigurable antenna...This paper presents a modification of an existing cognitive antenna design which contains two antennas: one is a sensing that covers the band from 1 - 11 GHz and the other is a hybrid triangular reconfigurable antenna. Two antennas are combined together to create a new design which called Cognitive Antenna. The new shape of the reconfigurable antenna will affect the cognitive antenna so as to work at two different frequencies via rotation by 180°. At each rotation, the antenna takes single frequency from number of possible frequencies that sensing antenna would find.展开更多
A new response-spectrum mode superposition method, entirely in real value form, is developed to analyze the maximum structural response under earthquake ground motion for generally damped linear systems with repeated ...A new response-spectrum mode superposition method, entirely in real value form, is developed to analyze the maximum structural response under earthquake ground motion for generally damped linear systems with repeated eigenvalues and defective eigenvectors. This algorithm has clear physical concepts and is similar to the complex complete quadratic combination (CCQC) method previously established. Since it can consider the effect of repeated eigenvalues, it is called the CCQC-R method, in which the correlation coefficients of high-order modal responses are enclosed in addition to the correlation coefficients in the normal CCQC method. As a result, the formulas for calculating the correlation coefficients of high-order modal responses are deduced in this study, including displacement, velocity and velocity-displacement correlation coefficients. Furthermore, the relationship between high-order displacement and velocity covariance is derived to make the CCQC-R algorithm only relevant to the high-order displacement response spectrum. Finally, a practical step-by-step integration procedure for calculating high-order displacement response spectrum is obtained by changing the earthquake ground motion input, which is evaluated by comparing it to the theory solution under the sine-wave input. The method derived here is suitable for generally linear systems with classical or non-classical damping.展开更多
基金supported in part by the Japan Ministry of Education,Sciences and Culture under Grants-in-Aid for Scientific Research(C)(21560471)the Green Industry Leading Program of Hubei University of Technology(CPYF2017003)the National Natural Science Foundation of China(1160147411461082)
文摘We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.
文摘A geothermal resource can be defined as a reservoir inside the Earth from which heat can be extracted economically Geothermal resources are classified on the basis of different aspects, such as heat source, heat transfer, reservoir tem perature, physical state, commercial utilization and geological settings. Unfortunately most of the current classifications that are used for geothermal systems are not complete. So, a combinational terminology of geological and tempera ture-based classifications would be more complete. This terminology can explain all geological situations, temperature and physical state of geothermal reservoir altogether. According to geological settings, in combinational terminology (from left to right), the class of geothermal resource’s name would be placed at first, then the physical state of reservoir (Liquid-dominated or Two-phase or Vapor-dominated) would be written and finally the class of the geothermal reser voir which is related to its temperature, is written.
文摘Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common procedure that provides a clear and continuous passage between the conventional distinction of either a strictly classical or a strictly quantized state. While path integration, among other procedures, provides an alternative route to connect classical and quantum expressions, it normally involves complicated, model-dependent, integrations. Our alternative procedures involve only model-independent procedures, and use more natural and straightforward integrations that are universal in kind. To introduce the basic procedures our presentation begins with familiar methods that are limited to basic, conventional, canonical quantum mechanical examples. In the final sections we illustrate how alternative quantization procedures, e.g., spin and affine quantizations, can also have smooth paths between classical and quantum stories, and with a few brief remarks, can also lead to similar stories for non-renormalizable covariant scalar fields as well as quantum gravity.
文摘Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization (DCCS) of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the MATLAB simula- tion outcomes. We obtain the same results of numerical treatment of our synchronization using simulation observations of our example.
基金by the National Natural Science Foundation of China(No.81700453).
文摘Current treatments for advanced hepatocellular carcinoma(HCC)have limited success in improving patients’quality of life and prolonging life expectancy.The clinical need for more efficient and safe therapies has contributed to the exploration of emerging strategies.Recently,there has been increased interest in oncolytic viruses(OVs)as a therapeutic modality for HCC.OVs undergo selective replication in cancerous tissues and kill tumor cells.Strikingly,pexastimogene devacirepvec(Pexa-Vec)was granted an orphan drug status in HCC by the U.S.Food and Drug Administration(FDA)in 2013.Meanwhile,dozens of OVs are being tested in HCC-directed clinical and preclinical trials.In this review,the pathogenesis and current therapies of HCC are outlined.Next,we summarize multiple OVs as single therapeutic agents for the treatment of HCC,which have demonstrated certain efficacy and lowtoxicity.Emerging carrier cell-,bioengineered cell mimetic-or nonbiological vehicle-mediated OV intravenous delivery systems in HCC therapy are described.In addition,we highlight the combination treatments between oncolytic virotherapy and other modalities.Finally,the clinical challenges and prospects of OV-based biotherapy are discussed,with the aim of continuing to develop a fascinating approach in HCC patients.
基金This project was supported by the National Natural Science Foundation of China(81972832)Project supported by College Students’innovation and entrepreneurship training program of Fujian Province(S202010386051).
文摘Sorafenib,a molecular targeted multi-kinase inhibitor,has received considerable interests in recent years due to its significant profiles of efficacy in cancer therapy.However,poor pharmacokinetic properties such as limited water solubility,rapid elimination and metabolism lead to low bioavailability,restricting its further clinical application.Over the past decade,with substantial progress achieved in the development of nanotechnology,various types of smart sorafenib nanoformulations have been developed to improve the targetability as well as the bioavailability of sorafenib.In this review,we summarize various aspects from the preparation and characterization to the evaluation of antitumor efficacy of numerous stimuli-responsive sorafenib nanodelivery systems,particularly with emphasis on their mechanism of drug release and tumor microenvironment response.In addition,this review makes great effort to summarize the nanosystem-based combination therapy of sorafenib with other antitumor agents,which can provide detailed information for further synergistic cancer therapy.In the final section of this review,we also provide a detailed discussion of future challenges and prospects of designing and developing ideal sorafenib nanoformulations for clinical cancer therapy.
文摘A novel combined model of the vibration control for the coupled flexiblesystem and its general mathematic description are developed. In presented model, active and passivecontrols as well as force and moment controls are combined into a single unit to achieve theefficient vibration control of the flexible structures by multi-approaches. Considering thecomplexity of the energy transmission in the vibrating system, the transmission channels of thepower flow transmitted into the foundation are discussed, and the general forces and thecorresponding velocities are combined into a single function, respectively. Under the controlstrategy of the minimum power flow, the transmission characteristics of the power flow areinvestigated. From the presented numerical examples, it is obvious that the analytical model iseffective, and both force and moment controls are able to depress vibration energy substantially.
基金This study was funded by the Xinjiang Production and Construction Corps Southern Xinjiang Key Industry Support Program Project,Grant Number 2019DB007.
文摘Aiming at the problems of large energy consumption and serious pollution of winter heating existing in the rural buildings in Southern Xinjiang,a combined active-passive heating system was proposed,and the simulation software was used to optimize the parameters of the system,according to the parameters obtained from the optimization,a test platform was built and winter heating test was carried out.The simulation results showed that the thickness of the air layer of 75 mm,the total area of the vent holes of 0.24 m^(2),and the thickness of the insulation layer of 120 mm were the optimal construction for the passive part;solar collector area of 28 m^(2),hot water storage tank volume of 1.4 m^(3),mass flow rate of 800 kg/h on the collector side,mass flow rate of 400 kg/h on the heat exchanger side,and output power of auxiliary heat source of 5∼9 kWwere the optimal constructions for active heating system.Test results showed that during the heating period,the system could provide sufficient heat to the room under different heating modes,and the indoor temperature reached over 18°C,which met the heating demand.The economic and environmental benefits of the system were analyzed,and the economic benefits of the systemwere better than coal-fired heating,and the CO_(2) emissionswere reduced by 3,292.25 kg compared with coalfiredheating.The results of the study showed that the combinedactive-passiveheating systemcouldeffectively solve the heating problems existing in rural buildings in Southern Xinjiang,and it also laid the theoretical foundation for the popularization of the combined heating systems.
基金supported by the National Natural Science Foundation of China(No.11972241)the Natural Science Foundation of Jiangsu Province (No.BK20191454)the Scientific Research Foundation of Suzhou University of Science and Technology (No.XKZ2017005)。
文摘The combined gradient representations for generalized Birkhoffian systems in event space are studied.Firstly,the definitions of six kinds of combined gradient systems and corresponding differential equations are given.Secondly,the conditions under which generalized Birkhoffian systems become combined gradient systems are obtained. Finally,the characteristics of combined gradient systems are used to study the stability of generalized Birkhoffian systems in event space. Seven examples are given to illustrate the results.
文摘The aging development in Shanghai shows speed, high degree of aging, the number of elderly people living alone increased and other trends, the contradiction between degree of aging and care become more prominent. However, the prevalence of current pension model has a pension without medical care, health care and pension separate and other issues, so the development of "medical support combined with pension" long-term care insurance system is imperative. Based on the study to explore parts of the country which operate basic pension model of"medical pension combination", we analyze the necessity and feasibility of the implementation of Shanghai "medical support combined with pension " long-term care insurance system, by summing up experiences and lessons, put forward some of the recommendations for the development in Shanghai "medical support combined with pension" type of long-term care system.
基金supported by National Natural Science Foundation of China(11271139)Guangdong Natural Science Foundation(2014A030313256,S2013040016144)+1 种基金Science and Technology Projects of Guangdong Province(2013B010101009)Tianhe Science and Technology Foundation of Guangzhou(201301YG027)
文摘The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform (TIP) combined with other systems, such as Floating Production Storage and Offloading (FPSO) system, Floating Production Unit (FPU) system, Tender Assisted Drilling (TAD) system, etc., has drawn the industry attention and increased significantly in the past few years. For the areas lacking of pipeline system, the use of TIP(s) combined with FPSO has been chosen to efficiently develop the deepwater fields. The TIP with a Tender Assisted Drilling system significantly reduces the payload of the platform and reduces the investment in the TIP system substantially. This opens the door for many new deepwater field developments to use the tension leg platform. The advantage of the TIP combined with a TAD system is more significant when several TIPs are used for the continuous development of the field. One of the applications for the TIP with a tender assisted drilling system can be in the development of an offshore marginal field. Owing to the increase of water depth, the conventional fixed platform model for the exploration of those fields becomes uneconomical. It also would be too expensive to use a large TIP structure for those marginal fields due to the large amount of initial investment. The TIP system with tender assisted drilling can be used to develop those fields economically. There are many marginal fields in China offshore, especially in shelf areas. The application of this field developing model, combined with the existing field developing experience in China, will open the door for many marginal field developments. This paper will review the application of the combined TIP system through some examples of completed/ongoing projects, and major technical issues encountered in those practices. The potential application of this technology in China deepwater development will be discussed in the end.
文摘Due to the mining,smelting,sewage irriga-tion,agricultural runoff,and development ofrural enterprises,combined pollution of Cd andZn in soil-rice systems has frequently oc-curred.This problem was studied by using thepot-culture imitative method combined withhemical analysis and mathematical models.
文摘This paper deals with knowledge representation of ESEP (Expert System for Earthqauke Prediction). Attending the characteristics of the knowledge in earthquake prediction domain, production representation and procedural representation are connected in the knowledge repesentation model of ESEP named ESEP/K, and three new ways of evidence conbination are proposed for production rules besides 'AND' and 'OR'.
文摘In this paper, a class of real-time parallel combined methods (RTPCM) of the digital simulation for a partitioned large system is presented. By means of combination of the parallelism across the system with the parallelism across the method, stiff and non-stiff subsystems are solved in parallel on parallel computer by a parallel Rosenbrock method and a parallel RK method, respectively. Their construction, convergence and numerical stability are discussed, and the digitalsimulation experiments are conducted.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (2002AA111010 2003AA001032)
文摘Resources are the base and core of education information, but current web education resources have no structure and it is still difficult to reuse them and make them can be self assembled and developed continually. According to the knowledge structure of course and text, the relation among knowledge points, knowledge units from three levels of media material, we can build education resource components, and build TKCM (Teaching Knowledge Combination Model) based on resource components. Builders can build and assemble knowledge system structure and make knowledge units can be self assembled, thus we can develop and consummate them continually. Users can make knowledge units can be self assembled and renewed, and build education knowledge system to satisfy users' demand under the form of education knowledge system.
文摘This paper addresses the design of practical communication strategies for multi-antenna amplify-and-forward and decode-and-forward relay systems. We show that simple linear techniques at the source and destination in conjunction with maximum ratio combining can provide an optimal transmission strategy in terms of received SNR without imposing a huge computational load over the relay node(s). Besides, the structures of precoding matrices are very similar at the source and relay nodes, which reduces the complexity as all nodes can play the role of source and relay nodes without changing their transmission structure. Numerical results show that the proposed transmission and reception techniques can improve the received SNR, and hence enhance the ergodic capacity.
文摘This paper presents a modification of an existing cognitive antenna design which contains two antennas: one is a sensing that covers the band from 1 - 11 GHz and the other is a hybrid triangular reconfigurable antenna. Two antennas are combined together to create a new design which called Cognitive Antenna. The new shape of the reconfigurable antenna will affect the cognitive antenna so as to work at two different frequencies via rotation by 180°. At each rotation, the antenna takes single frequency from number of possible frequencies that sensing antenna would find.
基金Natural Science Foundation of China under Grant Nos.51478440 and 51108429National Key Technology R&D Program under Grant No.2012BAK15B01
文摘A new response-spectrum mode superposition method, entirely in real value form, is developed to analyze the maximum structural response under earthquake ground motion for generally damped linear systems with repeated eigenvalues and defective eigenvectors. This algorithm has clear physical concepts and is similar to the complex complete quadratic combination (CCQC) method previously established. Since it can consider the effect of repeated eigenvalues, it is called the CCQC-R method, in which the correlation coefficients of high-order modal responses are enclosed in addition to the correlation coefficients in the normal CCQC method. As a result, the formulas for calculating the correlation coefficients of high-order modal responses are deduced in this study, including displacement, velocity and velocity-displacement correlation coefficients. Furthermore, the relationship between high-order displacement and velocity covariance is derived to make the CCQC-R algorithm only relevant to the high-order displacement response spectrum. Finally, a practical step-by-step integration procedure for calculating high-order displacement response spectrum is obtained by changing the earthquake ground motion input, which is evaluated by comparing it to the theory solution under the sine-wave input. The method derived here is suitable for generally linear systems with classical or non-classical damping.