The research project'Development and application of FCC additive for maximization of propylene and isobutylene'jointly undertaken by RIPP,the Baling Petrochemical Company(BPC)and the SINOPEC
Grice's maxims,which define the conditions for efficient spoken communication,can be adapted to the teaching of writing by providing both teachers and writers with a way of understanding successful and unsuccessfu...Grice's maxims,which define the conditions for efficient spoken communication,can be adapted to the teaching of writing by providing both teachers and writers with a way of understanding successful and unsuccessful written correspondence in mono-and cross-cultural settings.A survey of lay readers' responses to a sample letter which show that,while there are individual differences in the way these maxims are interpreted,readers expect clarity,brevity,and sincerity,and writing which fails to meet these expectations will be unfavorably received.Also discussed are the issues of contrastive rhetoric,and ways of helping writers to position themselves in relation to their real or imagined reader.展开更多
This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically deter...This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically determine the weight coefficients among the multiindices and also can obtain the exact and reliable evaluation results without subjectivity.展开更多
Large-scale epidemiological studies have found that hyperhomocysteinemia is a powerful, independent risk factor for Alzheimer's disease. Trillium tschonoskii maxim is a traditional Chinese medicine that is used to pr...Large-scale epidemiological studies have found that hyperhomocysteinemia is a powerful, independent risk factor for Alzheimer's disease. Trillium tschonoskii maxim is a traditional Chinese medicine that is used to promote memory. However, scientific understanding of its mechanism of action is limited. This report studied the potential neuroprotective effects of Trillium tschonoskii maxim extract against homocysteine-induced cognitive deficits. Rats were intravenously injected with homocysteine(400 μg/kg) for 14 days to induce a model of Alzheimer's disease. These rats were then intragastrically treated with Trillium tschonoskii maxim extract(0.125 or 0.25 g/kg) for 7 consecutive days. Open field test and Morris water maze test were conducted to measure spontaneous activity and learning and memory abilities. Western blot assay was used to detect the levels of Tau protein and other factors involved in Tau phosphorylation in the hippocampus. Immunohistochemical staining was used to examine Tau protein in the hippocampus. Golgi staining was applied to measure hippocampal dendritic spines. Our results demonstrated that homocysteine produced learning and memory deficits and increased levels of Tau phosphorylation, and diminished the activity of catalytic protein phosphatase 2A. The total number of hippocampal dendritic spines was also decreased. Trillium tschonoskii maxim extract treatment reversed the homocysteine-induced changes. The above results suggest that Trillium tschonoskii maxim extract can lessen homocysteine-induced abnormal Tau phosphorylation and improve cognitive deterioration such as that present in Alzheimer's disease.展开更多
Influenced by many factors,farmers remain very unfavorable position in market transaction and thus fail to ensure their reasonable benefits.In accordance with basic theory of microeconomics,this paper analyzes mutual ...Influenced by many factors,farmers remain very unfavorable position in market transaction and thus fail to ensure their reasonable benefits.In accordance with basic theory of microeconomics,this paper analyzes mutual relation between market of agricultural means of production and agricultural product market,compares economic decisions of agricultural means of production enterprises and agricultural product circulation service providers in monopoly condition and perfect competitive market,expounds influence of monopoly position of agricultural means of production enterprises and agricultural products service providers on economic benefits of farmers,and elaborates weak position and economic damage of farmers in transaction with various economic entities.Through analysis,it further recognizes necessity for protection of farmers'benefits and puts forward corresponding countermeasures:(1)regulating providers of agricultural means of production;(2)strengthening construction of agricultural product market circulation system;(3)improving organization of farmers;(4)setting up and improving production subsidy system of farmers.展开更多
Given a maximal subgroup M of a group G, a θ*-completion C of M is called an s*-completion if either C = G or there exists a subgroup D of G which is not a θ*-completion of M such that D contains C as a maximal subg...Given a maximal subgroup M of a group G, a θ*-completion C of M is called an s*-completion if either C = G or there exists a subgroup D of G which is not a θ*-completion of M such that D contains C as a maximal subgroup. In this paper, we obtain several results on s*-completions which imply G to be solvable or supersolvable.展开更多
The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Fi...The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.展开更多
In this paper we deal with the martingales in variable Lebesgue space over a probability space.We first prove several basic inequalities for conditional expectation operators and give several norm convergence conditio...In this paper we deal with the martingales in variable Lebesgue space over a probability space.We first prove several basic inequalities for conditional expectation operators and give several norm convergence conditions for martingales in variable Lebesgue space.The main aim of this paper is to investigate the boundedness of weak-type and strong-type Doob’s maximal operators in martingale Lebesgue space with a variable exponent.In particular,we present two kinds of weak-type Doob’s maximal inequalities and some necessary and sufficient conditions for strong-type Doob’s maximal inequalities.Finally,we provide two counterexamples to show that the strong-type inequality does not hold in general variable Lebesgue spaces with p>1.展开更多
Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in mo...Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways(i.e.,intercropping green manure in orchards or rotating green manure in cropland) to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent(CLUE-S) model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics(mainly croplands and orchards) were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011:The promotion of green manure planting in orchards(scenario 1) and the promotion of simultaneous green manure planting in orchards and croplands(scenario 2).The predictions were generally accurate based on the receiver operating characteristic(ROC) and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways.展开更多
CHINA and Africa have been a commu- nity of shared interests and shared destiny Their collaboration benefits not only the development of China and Africa but also promotes the unity and cooperation of developing count...CHINA and Africa have been a commu- nity of shared interests and shared destiny Their collaboration benefits not only the development of China and Africa but also promotes the unity and cooperation of developing countries. Health cooperation is a powerful testimony to the friendship between Chinese and African people. Based on win-win cooperation and aiming at the well-being of the people, China and Africa have attained fruitful results through health cooperation over the last five decades.展开更多
In this paper, we introduce the concept of weakly reducible maxi mal triangular algebras S*!which form a large class of maximal t riangular algebras. Let B be a weakly closed algebra containing S, we prove that the co...In this paper, we introduce the concept of weakly reducible maxi mal triangular algebras S*!which form a large class of maximal t riangular algebras. Let B be a weakly closed algebra containing S, we prove that the cohomology spaces Hn(S , B) ( n≥1) are trivial.展开更多
Relations between China and Malaysia have been developing steadily.Recently,See Chee Kong Leonard,Business Minister of Embassy of Malaysia in PRC,accepted an interview with Chinas Foreign Tradey and talked about the 4...Relations between China and Malaysia have been developing steadily.Recently,See Chee Kong Leonard,Business Minister of Embassy of Malaysia in PRC,accepted an interview with Chinas Foreign Tradey and talked about the 45 years of economic and trade cooperation and achievements of the two countries.展开更多
The Sino-U.S. trade imbalance and the related debate on RMB appreciation have attracted much attention in recent years. Judging objectively, however, the trade imbalance does not necessarily result in an imbalance in ...The Sino-U.S. trade imbalance and the related debate on RMB appreciation have attracted much attention in recent years. Judging objectively, however, the trade imbalance does not necessarily result in an imbalance in the distribution of trade benefits. By analyzing the distribution of benefits in Sino-U.S. trade from 1978 to 2007, this paper finds that bilateral trade has brought positive benefits to both sides, differentially in terms of production and consumption. Simply put, China has gained benefits for production yet suffered in terms of consumption, whereas the opposite is true for the U.S.. Moreover, even during periods in which the U.S. experienced a trade deficit, its citizens gained larger total individual benefits than those in a period of trade surplus. We argue, therefore, that appreciation of the RMB would reduce the trade benefits for both sides by almost the same margin, bringing little benefit to the United States.展开更多
To meet the requirements of a socialist market economy and overcome the inherent sharp contradictions of the former taxation system, China began reforming the structure of its tax system this year. The structural refo...To meet the requirements of a socialist market economy and overcome the inherent sharp contradictions of the former taxation system, China began reforming the structure of its tax system this year. The structural reform has been carried out under theguidelines of unifying the tax law, creating equal treatment, simplifying the tax system, building up a rational tax revenue sharing system, redressing distribution relationships, standardizing the mode展开更多
By adopting a complex formulation of Ohm’s law, we arrive at combined equations connecting the conductivities of conductors. The horizontal resistivity is equal to the inverse of Drude’s conductivity δo( ), and the...By adopting a complex formulation of Ohm’s law, we arrive at combined equations connecting the conductivities of conductors. The horizontal resistivity is equal to the inverse of Drude’s conductivity δo( ), and the vertical resistivity (ρy) is equal to the Hall’s conductivity ( δH). At high magnetic field, the horizontal conductivity becomes exceedingly small, whereas the vertical conductivity equals to Hall’s conductivity. The Hall’s conductivity is shown to represent the maximal conductivity of conductors. Drude’s and Hall’s conductivities are related by δo =δHωC , where ωC is the cyclotron frequency, and is the relaxation time. The quantization of Hall’s conductivity is attributed to the fact that the magnetic flux enclosed by the conductor is carried by electrons each with h/e, where h is the Planck’s constant and e is the electron’s charge. The Drude’s conductance is found to be equal to Hall's conductance provided the magnetic flux enclosed by the conductor is a multiple of h/e.展开更多
The problems of stability and stabilization for the discrete Takagi-Sugeno(T-S) fuzzy time-delay system are investigated.By constructing a discrete piecewise Lyapunov-Krasovskii function(PLKF) in each maximal over...The problems of stability and stabilization for the discrete Takagi-Sugeno(T-S) fuzzy time-delay system are investigated.By constructing a discrete piecewise Lyapunov-Krasovskii function(PLKF) in each maximal overlapped-rules group(MORG),a new sufficient stability condition for the open-loop discrete T-S fuzzy time-delay system is proposed and proved.Then the systematic design of the fuzzy controller is investigated via the parallel distributed compensation control scheme,and a new stabilization condition for the closed-loop discrete T-S fuzzy time-delay system is proposed.The above two sufficient conditions only require finding common matrices in each MORG.Compared with the common Lyapunov-Krasovskii function(CLKF) approach and the fuzzy Lyapunov-Krasovskii function(FLKF) approach,these proposed sufficient conditions can not only overcome the defect of finding common matrices in the whole feasible region but also largely reduce the number of linear matrix inequalities to be solved.Finally,simulation examples show that the proposed PLKF approach is effective.展开更多
The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC n...The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/6G.However, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.展开更多
文摘The research project'Development and application of FCC additive for maximization of propylene and isobutylene'jointly undertaken by RIPP,the Baling Petrochemical Company(BPC)and the SINOPEC
文摘Grice's maxims,which define the conditions for efficient spoken communication,can be adapted to the teaching of writing by providing both teachers and writers with a way of understanding successful and unsuccessful written correspondence in mono-and cross-cultural settings.A survey of lay readers' responses to a sample letter which show that,while there are individual differences in the way these maxims are interpreted,readers expect clarity,brevity,and sincerity,and writing which fails to meet these expectations will be unfavorably received.Also discussed are the issues of contrastive rhetoric,and ways of helping writers to position themselves in relation to their real or imagined reader.
文摘This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically determine the weight coefficients among the multiindices and also can obtain the exact and reliable evaluation results without subjectivity.
基金supported in part by grants from the National Natural Science Foundation of China,No.81260172,81660223the Opening Foundation of Hubei Key Laboratory of Biological Resource Protection and Utilization of China,No.PKLHB1318+2 种基金the Science and Technology Innovation Team Project of Hubei University for Nationalities of China,No.MY2011T005the Doctoral Fund of Hubei University for Nationalities of China,No.MY2012B015the Natural Science Foundation of Hubei Province of China,No.2017CFB451
文摘Large-scale epidemiological studies have found that hyperhomocysteinemia is a powerful, independent risk factor for Alzheimer's disease. Trillium tschonoskii maxim is a traditional Chinese medicine that is used to promote memory. However, scientific understanding of its mechanism of action is limited. This report studied the potential neuroprotective effects of Trillium tschonoskii maxim extract against homocysteine-induced cognitive deficits. Rats were intravenously injected with homocysteine(400 μg/kg) for 14 days to induce a model of Alzheimer's disease. These rats were then intragastrically treated with Trillium tschonoskii maxim extract(0.125 or 0.25 g/kg) for 7 consecutive days. Open field test and Morris water maze test were conducted to measure spontaneous activity and learning and memory abilities. Western blot assay was used to detect the levels of Tau protein and other factors involved in Tau phosphorylation in the hippocampus. Immunohistochemical staining was used to examine Tau protein in the hippocampus. Golgi staining was applied to measure hippocampal dendritic spines. Our results demonstrated that homocysteine produced learning and memory deficits and increased levels of Tau phosphorylation, and diminished the activity of catalytic protein phosphatase 2A. The total number of hippocampal dendritic spines was also decreased. Trillium tschonoskii maxim extract treatment reversed the homocysteine-induced changes. The above results suggest that Trillium tschonoskii maxim extract can lessen homocysteine-induced abnormal Tau phosphorylation and improve cognitive deterioration such as that present in Alzheimer's disease.
基金Supported by Fundamental Research Funds for the Central Universities in 2013(swu1309406)Key Educational Reform Project for Higher Education of Chongqing Municipal Education Commission in 2010(102310)General Educational Reform Project for Higher Education of Chongqing Municipal Education Commission in 2010(103321)
文摘Influenced by many factors,farmers remain very unfavorable position in market transaction and thus fail to ensure their reasonable benefits.In accordance with basic theory of microeconomics,this paper analyzes mutual relation between market of agricultural means of production and agricultural product market,compares economic decisions of agricultural means of production enterprises and agricultural product circulation service providers in monopoly condition and perfect competitive market,expounds influence of monopoly position of agricultural means of production enterprises and agricultural products service providers on economic benefits of farmers,and elaborates weak position and economic damage of farmers in transaction with various economic entities.Through analysis,it further recognizes necessity for protection of farmers'benefits and puts forward corresponding countermeasures:(1)regulating providers of agricultural means of production;(2)strengthening construction of agricultural product market circulation system;(3)improving organization of farmers;(4)setting up and improving production subsidy system of farmers.
文摘Given a maximal subgroup M of a group G, a θ*-completion C of M is called an s*-completion if either C = G or there exists a subgroup D of G which is not a θ*-completion of M such that D contains C as a maximal subgroup. In this paper, we obtain several results on s*-completions which imply G to be solvable or supersolvable.
基金Supported by 973 Project(2009CB421302)Innovation Project of Chinese Academy of Sciences(KZCX2-YW-127)Youth Science Foundation of China(41401025)
文摘The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.
文摘In this paper we deal with the martingales in variable Lebesgue space over a probability space.We first prove several basic inequalities for conditional expectation operators and give several norm convergence conditions for martingales in variable Lebesgue space.The main aim of this paper is to investigate the boundedness of weak-type and strong-type Doob’s maximal operators in martingale Lebesgue space with a variable exponent.In particular,we present two kinds of weak-type Doob’s maximal inequalities and some necessary and sufficient conditions for strong-type Doob’s maximal inequalities.Finally,we provide two counterexamples to show that the strong-type inequality does not hold in general variable Lebesgue spaces with p>1.
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China(20110300501-01)the Special Fund for First-Class University (4572-18101510)
文摘Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways(i.e.,intercropping green manure in orchards or rotating green manure in cropland) to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent(CLUE-S) model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics(mainly croplands and orchards) were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011:The promotion of green manure planting in orchards(scenario 1) and the promotion of simultaneous green manure planting in orchards and croplands(scenario 2).The predictions were generally accurate based on the receiver operating characteristic(ROC) and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways.
文摘CHINA and Africa have been a commu- nity of shared interests and shared destiny Their collaboration benefits not only the development of China and Africa but also promotes the unity and cooperation of developing countries. Health cooperation is a powerful testimony to the friendship between Chinese and African people. Based on win-win cooperation and aiming at the well-being of the people, China and Africa have attained fruitful results through health cooperation over the last five decades.
文摘In this paper, we introduce the concept of weakly reducible maxi mal triangular algebras S*!which form a large class of maximal t riangular algebras. Let B be a weakly closed algebra containing S, we prove that the cohomology spaces Hn(S , B) ( n≥1) are trivial.
文摘Relations between China and Malaysia have been developing steadily.Recently,See Chee Kong Leonard,Business Minister of Embassy of Malaysia in PRC,accepted an interview with Chinas Foreign Tradey and talked about the 45 years of economic and trade cooperation and achievements of the two countries.
文摘The Sino-U.S. trade imbalance and the related debate on RMB appreciation have attracted much attention in recent years. Judging objectively, however, the trade imbalance does not necessarily result in an imbalance in the distribution of trade benefits. By analyzing the distribution of benefits in Sino-U.S. trade from 1978 to 2007, this paper finds that bilateral trade has brought positive benefits to both sides, differentially in terms of production and consumption. Simply put, China has gained benefits for production yet suffered in terms of consumption, whereas the opposite is true for the U.S.. Moreover, even during periods in which the U.S. experienced a trade deficit, its citizens gained larger total individual benefits than those in a period of trade surplus. We argue, therefore, that appreciation of the RMB would reduce the trade benefits for both sides by almost the same margin, bringing little benefit to the United States.
文摘To meet the requirements of a socialist market economy and overcome the inherent sharp contradictions of the former taxation system, China began reforming the structure of its tax system this year. The structural reform has been carried out under theguidelines of unifying the tax law, creating equal treatment, simplifying the tax system, building up a rational tax revenue sharing system, redressing distribution relationships, standardizing the mode
文摘By adopting a complex formulation of Ohm’s law, we arrive at combined equations connecting the conductivities of conductors. The horizontal resistivity is equal to the inverse of Drude’s conductivity δo( ), and the vertical resistivity (ρy) is equal to the Hall’s conductivity ( δH). At high magnetic field, the horizontal conductivity becomes exceedingly small, whereas the vertical conductivity equals to Hall’s conductivity. The Hall’s conductivity is shown to represent the maximal conductivity of conductors. Drude’s and Hall’s conductivities are related by δo =δHωC , where ωC is the cyclotron frequency, and is the relaxation time. The quantization of Hall’s conductivity is attributed to the fact that the magnetic flux enclosed by the conductor is carried by electrons each with h/e, where h is the Planck’s constant and e is the electron’s charge. The Drude’s conductance is found to be equal to Hall's conductance provided the magnetic flux enclosed by the conductor is a multiple of h/e.
基金supported in part by the Scientific Research Project of Heilongjiang Province Education Bureau(12541200)
文摘The problems of stability and stabilization for the discrete Takagi-Sugeno(T-S) fuzzy time-delay system are investigated.By constructing a discrete piecewise Lyapunov-Krasovskii function(PLKF) in each maximal overlapped-rules group(MORG),a new sufficient stability condition for the open-loop discrete T-S fuzzy time-delay system is proposed and proved.Then the systematic design of the fuzzy controller is investigated via the parallel distributed compensation control scheme,and a new stabilization condition for the closed-loop discrete T-S fuzzy time-delay system is proposed.The above two sufficient conditions only require finding common matrices in each MORG.Compared with the common Lyapunov-Krasovskii function(CLKF) approach and the fuzzy Lyapunov-Krasovskii function(FLKF) approach,these proposed sufficient conditions can not only overcome the defect of finding common matrices in the whole feasible region but also largely reduce the number of linear matrix inequalities to be solved.Finally,simulation examples show that the proposed PLKF approach is effective.
基金supported in part by the National Natural Science Foundation of China under Grants 62201105,62331017,and 62075024in part by the Natural Science Foundation of Chongqing under Grant cstc2021jcyj-msxmX0404+1 种基金in part by the Chongqing Municipal Education Commission under Grant KJQN202100643in part by Guangdong Basic and Applied Basic Research Foundation under Grant 2022A1515110056.
文摘The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/6G.However, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.