As the global economy navigates through a complex landscape of uncertainty and shifting dynamics,the Chinese economy stands out for its remarkable resilience,inherent vitality,and steadfast commitment to a transformat...As the global economy navigates through a complex landscape of uncertainty and shifting dynamics,the Chinese economy stands out for its remarkable resilience,inherent vitality,and steadfast commitment to a transformative,high-quality development path.The latest economic indicators,strategic policy guidance from the Central Economic Work Conference,and a surge in international confidence collectively present a picture of an economy not merely recovering,but actively building its new growth engines.China is transitioning towards a more sustainable and innovation-driven model,with new quality productive forces playing an increasingly prominent role.展开更多
Since the outbreak of the Ukraine crisis,the European Union(EU)has imposed multiple rounds of systematic economic sanctions on Russia,covering key areas such as finance,energy,trade,and technology,in an attempt to wea...Since the outbreak of the Ukraine crisis,the European Union(EU)has imposed multiple rounds of systematic economic sanctions on Russia,covering key areas such as finance,energy,trade,and technology,in an attempt to weaken Russia's war capacity.In response,Russia has taken forceful measures,legitimizing its counteractions through legal tools,hedging EU sanctions with economic and financial instruments,and leveraging resources as a“weapon.”Additionally,Russia has reinforced its defense through internal structural adjustments,seeking strategic breakthroughs by diversifying foreign relations.These measures have effectively mitigated the impact of EU sanctions,increased EU costs in carrying out the sanctions,and prevented the EU from achieving its intended political objectives.Currently,Russia's military operation in Ukraine continues,with its foreign cooperation pattern and development path undergoing significant shifts.Specifically,Russia is accelerating its“turn to the East”in terms of foreign economic relations,and its development model is becoming increasingly conservative and security-oriented.As its confrontation with the EU enters a prolonged phase,Russia,while striving to maintain overall economic stability,faces numerous challenges and long-term risks threatening its economic transformation and reorientation of foreign cooperation.The difficulties awaiting its future counteractions will even increase.展开更多
How is a nation’s embrace of snow and ice shaping a new cultural identity and igniting a multi-trillion-yuan economic boom?ADRIAAN Smit now cannot imagine a life without snowboarding,a passion that has become central...How is a nation’s embrace of snow and ice shaping a new cultural identity and igniting a multi-trillion-yuan economic boom?ADRIAAN Smit now cannot imagine a life without snowboarding,a passion that has become central to his world.He is excited to witness how winter sports are fostering a new winter culture in China.Listening to Smit speaking so enthusiastically about the slopes,one might assume he was raised in a region where snow sports are a way of life,but the fact is quite the contrary.展开更多
Decarbonising the building sector,particularly residential heating,represents a critical challenge for achieving carbon-neutral energy systems.Efficient solutions must integrate both technological performance and rene...Decarbonising the building sector,particularly residential heating,represents a critical challenge for achieving carbon-neutral energy systems.Efficient solutions must integrate both technological performance and renewable energy sources while considering operational constraints of existing systems.This study investigates a hybrid heating system combining a natural gas boiler(NGB)with an air-to-water heat pump(AWHP),evaluated through a combination of laboratory experiments and dynamic modelling.A prototype developed in the Electrical and Energy Engineering Laboratory enabled the characterization of both heat generators,the collection of experimental data,and the calibration of a MATLAB/Simulink model,including emissions and exhaust analyses.Sensitivity analyses were performed to identify optimal configurations for energy efficiency and system control,accounting for interactions between subsystems.Results highlight that hybridisation significantly improves primary energy efficiency and reduces fuel consumption compared to conventional NGB-only systems.Environmental performance,assessed through CO_(2) and NOx emissions and renewable energy integration,demonstrates the benefits of partial electrification in the residential sector.Economic assessment further quantifies decarbonization costs and fuel savings,illustrating tradeoffs between low-capital,moderate-performance systems and high-efficiency,high-renewable solutions requiring larger investments.The analysis shows that strategic decisions for residential decarbonisation cannot be separated from system-wide considerations,including control strategies,component integration,and economic feasibility.The study underlines the importance of hybrid and renewable-based solutions as pivotal pathways for energy transition in the residential building sector.展开更多
To enhance the low-carbon economic efficiency and increase the utilization of renewable energy within integrated energy systems(IES),this paper proposes a low-carbon dispatch model integrating power-to-gas(P2G),carbon...To enhance the low-carbon economic efficiency and increase the utilization of renewable energy within integrated energy systems(IES),this paper proposes a low-carbon dispatch model integrating power-to-gas(P2G),carbon capture and storage(CCS),hydrogen fuel cell(HFC),and combined heat and power(CHP).The P2G process is refined into a two-stage structure,and HFC is introduced to enhance hydrogen utilization.Together with CCS and CHP,these devices form a multi-energy conversion system coupling electricity,heat,cooling,and gas.A laddertype carbon trading approach is adopted to flexibly manage carbon output by leveraging marginal cost adjustments.To evaluate the resilience of the proposed low-carbon scheduling strategy involving multiple energy units under the variability of renewable energy,a two-level robust optimization framework is developed.This model captures the most adverse scenarios of wind and solar generation.The dispatch strategy is validated against these extreme conditions to demonstrate its flexibility and effectiveness.The problem is solved using the GUROBI optimization tool.Results from simulations indicate that themodel increases renewable energy integration by 39.1%,and achieves reductions of 15.96%in carbon emissions and 16.29%in operational expenditures.The results demonstrate that the strategy ensures both economic efficiency and environmental performance under uncertain conditions.Compared with existing studies that separately model two-stage P2G or CCS devices,this paper integrates HFC,CHP,and CCS into a unified dispatchable system,enabling refined hydrogen utilization and flexible carbon circulation.Furthermore,the introduction of a laddertype carbon pricing mechanism,combined with multi-energy storage participation in implicit demand response,creates a dynamic and cost-sensitive dispatch framework.These modeling strategies go beyond conventional linear IES formulations and provide more realistic system representations.The proposed approach not only deepens the coupling among electric,thermal,and gas systems,but also offers a feasible pathway for high-penetration renewable integration in low-carbon energy systems.展开更多
China’s commitment to high-standard opening-upduring its 15th Five-Year Plan period offers Europe analternative approach to economic resilience.AT a time when much of the Westernworld is retreating behind tariff wall...China’s commitment to high-standard opening-upduring its 15th Five-Year Plan period offers Europe analternative approach to economic resilience.AT a time when much of the Westernworld is retreating behind tariff wallsand industrial policy rhetoric framedaround“unfair competition,”China ismoving steadfastly in the opposite direction.展开更多
In the countryside of east Zhejiang Province,a quiet village has hit a home run.Xujiadai,once a place known for pig farming and environmental pollution,is drawing visitors from across China with a sport still uncommon...In the countryside of east Zhejiang Province,a quiet village has hit a home run.Xujiadai,once a place known for pig farming and environmental pollution,is drawing visitors from across China with a sport still uncommon in the country:baseball.展开更多
The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supporte...The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supported Africa in addressing historical injustices at diplomatic and political levels and firmly backed South Africa in hosting the G20 Leaders’Summit,further deepening China-Africa strategic mutual trust.展开更多
Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional constructio...Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional construction land, and to discuss the decision direction for economical and intensive utilization of the regional con- struction land. The results showed that, the population based land utilization both in Zunyi and the city districts and counties indicated extensive trend. The economy- based land utilization in Zunyi City, as well as in Huichun, Zunyi and Tongzi County presented intensive trend, however the other districts and counties were in extensive tendency. It concluded that the economical and intensive utilization of construction land should be focused on the rural collective construction land, and the potential tapping of rural collective construction land in rocky desertification area should be the first priority, otherwise, the regional economic development was unbalanced be- tween different district and county in Zunyi.展开更多
Effects of chemical compositions, finish rolling temperature, isothermal temperature on runout table and coiling temperature on microstructure and mechanical properties of economical dual phase steel produced on CSP l...Effects of chemical compositions, finish rolling temperature, isothermal temperature on runout table and coiling temperature on microstructure and mechanical properties of economical dual phase steel produced on CSP line were investigated. Experimental results showed that martensite volume fraction could be enhanced and banding mi- crostructure could be reduced by controlling Mn, Si contents and applying proper finish rolling temperature. Opti- mized processing-parameters were obtained for DP580 production on CSP line of Wuhan Iron and Steel （group） Co （WISCO） in China. Optimal mierostructure and mechanical properties could be achieved when the strip was finished rolling at the range of 790 to 830 ~C, isothermally holding at 680 to 740 ~C and coiling below 250 ~C.展开更多
AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopi...AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopic treatment of benign foregut strictures between January 2014 and May 2017 was analyzed. A control group of non-stented patients who underwent three endoscopic dilations was compared to patients who underwent LAMS placement. Statistical tests performed included independent t-tests and fiveparameter regression analysis RESULTS Nine hundred and ninety-eight foregut endoscopic dilations were performed between January 2014 and May 2017. 15 patients underwent endoscopic LAMS placement for treatment of benign foregut stricture. Thirty-six patients with recurrent benign foregut strictures underwent three or more endoscopic dilations without stent placement. The cost ratio of endoscopic dilation to LAMS(stent, placement and retrieval) is 5.77. Cost effective analysis demonstrated LAMS to be economical after three endoscopic dilation overall.LAMS was cost effective after two dilations in the Postsurgical stricture subgroup. CONCLUSION Endoscopists should consider LAMS for the treatment of benign foregut strictures if symptoms persist past three endoscopic dilations. Post-surgical strictures may benefit from LAMS if symptoms persist after two dilations in a post-surgical. Early intervention with LAMS appears to be a clinically and economically viable option for durable symptomatic relief in patients with these strictures.展开更多
With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically import...With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959,1982,1992–1993,2004,2009 and 2015.A total of 37 species of economically important invertebrates,belonging to 5 orders,24 families,were captured.The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015.Oratosquilla oratoria and Loligo spp.were the most dominant species in the past 30 years,the biomass proportion of O.oratoria increased gradually in both May and August from 1982 to 2015.Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to 2004 and then increased in 2015.Similarly,the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015.Overall,although the proportions of invertebrates have increased,the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the“double-control”of the total number and engine power of fishing vessels and summer moratorium of fishing.展开更多
This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractiona...This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractional-order integral, the effective sliding mode controller is designed to realize the asymptotical stability of fractional-order chaotic economical systems. Comparing with the existing results, the main results in this paper are more practical and rigorous. Simulation results show the effectiveness and feasibility of the proposed sliding mode control method.展开更多
Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the devel...Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use.展开更多
According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system wer...According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too.展开更多
A new family of economical duplex stainless steels in which N or Mn was substituted for Ni with composi- tion of 22Cr-8.0Mn-xNi-1.0Mo-0.7Cu-0.7W-0.3N （x = 0.5 -- 2.0） have been developed by examining the micro- stru...A new family of economical duplex stainless steels in which N or Mn was substituted for Ni with composi- tion of 22Cr-8.0Mn-xNi-1.0Mo-0.7Cu-0.7W-0.3N （x = 0.5 -- 2.0） have been developed by examining the micro- structure, mechanical and corrosion properties of these alloys. The results show that these alloys have a balanced ferrite-austenite relation. In addition, the alloys are free of precipitation of sigma phase and Cr-nitride when solution- treated at 750 to 1300℃ for 30 min. The yield strength, tensile strength and fracture elongation values of experi- mental alloys solution-treated at 1050 ℃ for 30 min are about 500, 750 MPa and 40.0%, respectively. Low-temper- ature impact properties can be improved distinctly with the increase of nickel content. Among the designed DSS al- loys, the alloy with Ni of 2.0% is found to be an optimum alloy with proper phase proportion, better low-tempera- ture impact properties and higher pitting corrosion resistance compared with those o~ other alloys. The mechanical and corrosion properties and lower production cost of the designed DSSs are better than those of AISI 304.展开更多
This paper analyzes the relationship between rural finance and the rural economy of Sichuan Province from 1999 to 2009 by using the sequential growth rate of the gross value of farming, forestry, animal husbandry and ...This paper analyzes the relationship between rural finance and the rural economy of Sichuan Province from 1999 to 2009 by using the sequential growth rate of the gross value of farming, forestry, animal husbandry and fishery and the sequential growth rate of the per capital total income of rural households as the indicators of rural economic development; and taking the volume of deposit, volume of credit, volume of agricultural credit and the credit volume of township enterprises as the indicators of rural financial development; as well as the method of grey correlation analysis. The results show that there is an obvious positive correlation between them, and the development of country finance has the closest connection with the sequential growth rate of farming, forestry, animal husbandry, sideline production and fishery. The loan scale of township enterprises has the biggest influence on the increase of the rural economy. The countermeasures are put forward, covering optimizing investment structure; supporting the development of township enterprises; encouraging loan; actively lightening the financial difficulties in the process of developing rural economy; innovating and exploring; and promoting the diversified development of rural finance.展开更多
Taking Huaian as an example,the rural economic and environmental problems in economically underdeveloped areas are expounded.The results show that rural areas in economically underdeveloped areas confront with lagged ...Taking Huaian as an example,the rural economic and environmental problems in economically underdeveloped areas are expounded.The results show that rural areas in economically underdeveloped areas confront with lagged economic development,serious environmental pollutionand scarce shortage of equipments for treating environmental pollution.The causes of problems are analyzed,including inadequate fiscal supportfrom the local government;unscientific system for assessing government officers' performances;backward ideas in environmental protection and im-perfect laws and regulations on environmental protection.Based on these causes,the strategy of employing the circular economy to promote the co-ordinated development of rural environment and economy in economically underdeveloped areas is put forward.The strategy covers transformingthe way of agricultural production;adjusting agricultural production structure;positively collecting funds and increasing the input on handling rural en-vironmental problems;strengthening the efforts on promotion and education,and forming the healthy habits of consumption;enforcing supervisionand establishing a professional administration team for protecting rural environment;laying stress on rural technological innovation and strengtheningthe force of expansion;accelerating the path of industrialization and promoting the industrialization of villages and towns vigorously.展开更多
This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiave...This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiavello C 2003 Phys. Rev. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y, Lamata Let al, 2007 Phys. Rev. Lett. 98 150502] in which M must be odd.展开更多
Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland cir...Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland circulation from supply and demand of land.Results showed that non-agricultural employment,social security level,and regional economic development level are key factors.In view of these factors,it is recommended to improve rural labor quality,establish perfect rural social security system,and constantly improve rural security level,which are fundamental ways to promoting farmland circulation and improve circulation market.展开更多
文摘As the global economy navigates through a complex landscape of uncertainty and shifting dynamics,the Chinese economy stands out for its remarkable resilience,inherent vitality,and steadfast commitment to a transformative,high-quality development path.The latest economic indicators,strategic policy guidance from the Central Economic Work Conference,and a surge in international confidence collectively present a picture of an economy not merely recovering,but actively building its new growth engines.China is transitioning towards a more sustainable and innovation-driven model,with new quality productive forces playing an increasingly prominent role.
文摘Since the outbreak of the Ukraine crisis,the European Union(EU)has imposed multiple rounds of systematic economic sanctions on Russia,covering key areas such as finance,energy,trade,and technology,in an attempt to weaken Russia's war capacity.In response,Russia has taken forceful measures,legitimizing its counteractions through legal tools,hedging EU sanctions with economic and financial instruments,and leveraging resources as a“weapon.”Additionally,Russia has reinforced its defense through internal structural adjustments,seeking strategic breakthroughs by diversifying foreign relations.These measures have effectively mitigated the impact of EU sanctions,increased EU costs in carrying out the sanctions,and prevented the EU from achieving its intended political objectives.Currently,Russia's military operation in Ukraine continues,with its foreign cooperation pattern and development path undergoing significant shifts.Specifically,Russia is accelerating its“turn to the East”in terms of foreign economic relations,and its development model is becoming increasingly conservative and security-oriented.As its confrontation with the EU enters a prolonged phase,Russia,while striving to maintain overall economic stability,faces numerous challenges and long-term risks threatening its economic transformation and reorientation of foreign cooperation.The difficulties awaiting its future counteractions will even increase.
文摘How is a nation’s embrace of snow and ice shaping a new cultural identity and igniting a multi-trillion-yuan economic boom?ADRIAAN Smit now cannot imagine a life without snowboarding,a passion that has become central to his world.He is excited to witness how winter sports are fostering a new winter culture in China.Listening to Smit speaking so enthusiastically about the slopes,one might assume he was raised in a region where snow sports are a way of life,but the fact is quite the contrary.
基金supported by European Commission and is a part of the HORIZON2020 project RES Heatfunding from the European Union’s Horizon 2020 program in the field of research and innovation on the basis of grant agreement No.956255.
文摘Decarbonising the building sector,particularly residential heating,represents a critical challenge for achieving carbon-neutral energy systems.Efficient solutions must integrate both technological performance and renewable energy sources while considering operational constraints of existing systems.This study investigates a hybrid heating system combining a natural gas boiler(NGB)with an air-to-water heat pump(AWHP),evaluated through a combination of laboratory experiments and dynamic modelling.A prototype developed in the Electrical and Energy Engineering Laboratory enabled the characterization of both heat generators,the collection of experimental data,and the calibration of a MATLAB/Simulink model,including emissions and exhaust analyses.Sensitivity analyses were performed to identify optimal configurations for energy efficiency and system control,accounting for interactions between subsystems.Results highlight that hybridisation significantly improves primary energy efficiency and reduces fuel consumption compared to conventional NGB-only systems.Environmental performance,assessed through CO_(2) and NOx emissions and renewable energy integration,demonstrates the benefits of partial electrification in the residential sector.Economic assessment further quantifies decarbonization costs and fuel savings,illustrating tradeoffs between low-capital,moderate-performance systems and high-efficiency,high-renewable solutions requiring larger investments.The analysis shows that strategic decisions for residential decarbonisation cannot be separated from system-wide considerations,including control strategies,component integration,and economic feasibility.The study underlines the importance of hybrid and renewable-based solutions as pivotal pathways for energy transition in the residential building sector.
基金supported by the Key Project of Shanghai(Project Number A1-0224-25-002-02-040,Municipal Key Course—Heat Transfer)funded by the National Natural Science Foundation of China(Grant No.52077137).
文摘To enhance the low-carbon economic efficiency and increase the utilization of renewable energy within integrated energy systems(IES),this paper proposes a low-carbon dispatch model integrating power-to-gas(P2G),carbon capture and storage(CCS),hydrogen fuel cell(HFC),and combined heat and power(CHP).The P2G process is refined into a two-stage structure,and HFC is introduced to enhance hydrogen utilization.Together with CCS and CHP,these devices form a multi-energy conversion system coupling electricity,heat,cooling,and gas.A laddertype carbon trading approach is adopted to flexibly manage carbon output by leveraging marginal cost adjustments.To evaluate the resilience of the proposed low-carbon scheduling strategy involving multiple energy units under the variability of renewable energy,a two-level robust optimization framework is developed.This model captures the most adverse scenarios of wind and solar generation.The dispatch strategy is validated against these extreme conditions to demonstrate its flexibility and effectiveness.The problem is solved using the GUROBI optimization tool.Results from simulations indicate that themodel increases renewable energy integration by 39.1%,and achieves reductions of 15.96%in carbon emissions and 16.29%in operational expenditures.The results demonstrate that the strategy ensures both economic efficiency and environmental performance under uncertain conditions.Compared with existing studies that separately model two-stage P2G or CCS devices,this paper integrates HFC,CHP,and CCS into a unified dispatchable system,enabling refined hydrogen utilization and flexible carbon circulation.Furthermore,the introduction of a laddertype carbon pricing mechanism,combined with multi-energy storage participation in implicit demand response,creates a dynamic and cost-sensitive dispatch framework.These modeling strategies go beyond conventional linear IES formulations and provide more realistic system representations.The proposed approach not only deepens the coupling among electric,thermal,and gas systems,but also offers a feasible pathway for high-penetration renewable integration in low-carbon energy systems.
文摘China’s commitment to high-standard opening-upduring its 15th Five-Year Plan period offers Europe analternative approach to economic resilience.AT a time when much of the Westernworld is retreating behind tariff wallsand industrial policy rhetoric framedaround“unfair competition,”China ismoving steadfastly in the opposite direction.
文摘In the countryside of east Zhejiang Province,a quiet village has hit a home run.Xujiadai,once a place known for pig farming and environmental pollution,is drawing visitors from across China with a sport still uncommon in the country:baseball.
文摘The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supported Africa in addressing historical injustices at diplomatic and political levels and firmly backed South Africa in hosting the G20 Leaders’Summit,further deepening China-Africa strategic mutual trust.
基金Supported by Guiyang Science and Technology Project([2012103]81)Guizhou Science and Technology Project([2012]3058)~~
文摘Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional construction land, and to discuss the decision direction for economical and intensive utilization of the regional con- struction land. The results showed that, the population based land utilization both in Zunyi and the city districts and counties indicated extensive trend. The economy- based land utilization in Zunyi City, as well as in Huichun, Zunyi and Tongzi County presented intensive trend, however the other districts and counties were in extensive tendency. It concluded that the economical and intensive utilization of construction land should be focused on the rural collective construction land, and the potential tapping of rural collective construction land in rocky desertification area should be the first priority, otherwise, the regional economic development was unbalanced be- tween different district and county in Zunyi.
文摘Effects of chemical compositions, finish rolling temperature, isothermal temperature on runout table and coiling temperature on microstructure and mechanical properties of economical dual phase steel produced on CSP line were investigated. Experimental results showed that martensite volume fraction could be enhanced and banding mi- crostructure could be reduced by controlling Mn, Si contents and applying proper finish rolling temperature. Opti- mized processing-parameters were obtained for DP580 production on CSP line of Wuhan Iron and Steel （group） Co （WISCO） in China. Optimal mierostructure and mechanical properties could be achieved when the strip was finished rolling at the range of 790 to 830 ~C, isothermally holding at 680 to 740 ~C and coiling below 250 ~C.
文摘AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopic treatment of benign foregut strictures between January 2014 and May 2017 was analyzed. A control group of non-stented patients who underwent three endoscopic dilations was compared to patients who underwent LAMS placement. Statistical tests performed included independent t-tests and fiveparameter regression analysis RESULTS Nine hundred and ninety-eight foregut endoscopic dilations were performed between January 2014 and May 2017. 15 patients underwent endoscopic LAMS placement for treatment of benign foregut stricture. Thirty-six patients with recurrent benign foregut strictures underwent three or more endoscopic dilations without stent placement. The cost ratio of endoscopic dilation to LAMS(stent, placement and retrieval) is 5.77. Cost effective analysis demonstrated LAMS to be economical after three endoscopic dilation overall.LAMS was cost effective after two dilations in the Postsurgical stricture subgroup. CONCLUSION Endoscopists should consider LAMS for the treatment of benign foregut strictures if symptoms persist past three endoscopic dilations. Post-surgical strictures may benefit from LAMS if symptoms persist after two dilations in a post-surgical. Early intervention with LAMS appears to be a clinically and economically viable option for durable symptomatic relief in patients with these strictures.
基金The National Key Research and Development Program of China under contract No.2018YFD0900902the National Key Basic Research Development Program(973 Program)of China under contract No.2015CB453303+1 种基金the Special Funds for Taishan Scholar Project of Shandong Provincethe AoShan Talents Cultivation Program supported by Qingdao National Laboratory for Marine Science and Technology under contract No.2017ASTCP-ES07
文摘With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959,1982,1992–1993,2004,2009 and 2015.A total of 37 species of economically important invertebrates,belonging to 5 orders,24 families,were captured.The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015.Oratosquilla oratoria and Loligo spp.were the most dominant species in the past 30 years,the biomass proportion of O.oratoria increased gradually in both May and August from 1982 to 2015.Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to 2004 and then increased in 2015.Similarly,the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015.Overall,although the proportions of invertebrates have increased,the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the“double-control”of the total number and engine power of fishing vessels and summer moratorium of fishing.
基金supported by the National Natural Science Foundation of China(Grant Nos.51207173 and 51277192)
文摘This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractional-order integral, the effective sliding mode controller is designed to realize the asymptotical stability of fractional-order chaotic economical systems. Comparing with the existing results, the main results in this paper are more practical and rigorous. Simulation results show the effectiveness and feasibility of the proposed sliding mode control method.
基金Supported by Special Research Fund for the Nonprofit Industry of the Ministry of Land and Resources(201111010)
文摘Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use.
文摘According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too.
基金Sponsored by Innovation Fund of Education Commission of Shanghai Municipality of China (09yz20)
文摘A new family of economical duplex stainless steels in which N or Mn was substituted for Ni with composi- tion of 22Cr-8.0Mn-xNi-1.0Mo-0.7Cu-0.7W-0.3N （x = 0.5 -- 2.0） have been developed by examining the micro- structure, mechanical and corrosion properties of these alloys. The results show that these alloys have a balanced ferrite-austenite relation. In addition, the alloys are free of precipitation of sigma phase and Cr-nitride when solution- treated at 750 to 1300℃ for 30 min. The yield strength, tensile strength and fracture elongation values of experi- mental alloys solution-treated at 1050 ℃ for 30 min are about 500, 750 MPa and 40.0%, respectively. Low-temper- ature impact properties can be improved distinctly with the increase of nickel content. Among the designed DSS al- loys, the alloy with Ni of 2.0% is found to be an optimum alloy with proper phase proportion, better low-tempera- ture impact properties and higher pitting corrosion resistance compared with those o~ other alloys. The mechanical and corrosion properties and lower production cost of the designed DSSs are better than those of AISI 304.
文摘This paper analyzes the relationship between rural finance and the rural economy of Sichuan Province from 1999 to 2009 by using the sequential growth rate of the gross value of farming, forestry, animal husbandry and fishery and the sequential growth rate of the per capital total income of rural households as the indicators of rural economic development; and taking the volume of deposit, volume of credit, volume of agricultural credit and the credit volume of township enterprises as the indicators of rural financial development; as well as the method of grey correlation analysis. The results show that there is an obvious positive correlation between them, and the development of country finance has the closest connection with the sequential growth rate of farming, forestry, animal husbandry, sideline production and fishery. The loan scale of township enterprises has the biggest influence on the increase of the rural economy. The countermeasures are put forward, covering optimizing investment structure; supporting the development of township enterprises; encouraging loan; actively lightening the financial difficulties in the process of developing rural economy; innovating and exploring; and promoting the diversified development of rural finance.
基金Supported by Science and Technology Programs of Huaiyin Institute of Technology (HGB0916)
文摘Taking Huaian as an example,the rural economic and environmental problems in economically underdeveloped areas are expounded.The results show that rural areas in economically underdeveloped areas confront with lagged economic development,serious environmental pollutionand scarce shortage of equipments for treating environmental pollution.The causes of problems are analyzed,including inadequate fiscal supportfrom the local government;unscientific system for assessing government officers' performances;backward ideas in environmental protection and im-perfect laws and regulations on environmental protection.Based on these causes,the strategy of employing the circular economy to promote the co-ordinated development of rural environment and economy in economically underdeveloped areas is put forward.The strategy covers transformingthe way of agricultural production;adjusting agricultural production structure;positively collecting funds and increasing the input on handling rural en-vironmental problems;strengthening the efforts on promotion and education,and forming the healthy habits of consumption;enforcing supervisionand establishing a professional administration team for protecting rural environment;laying stress on rural technological innovation and strengtheningthe force of expansion;accelerating the path of industrialization and promoting the industrialization of villages and towns vigorously.
基金supported by the National Natural Science Foundation of China (Grant No 10674001)the Program of the Education Department of Anhui Province of China (Grant No KJ2007A002)
文摘This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D＇Ar]ano G M and Macchiavello C 2003 Phys. Rev. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y, Lamata Let al, 2007 Phys. Rev. Lett. 98 150502] in which M must be odd.
基金the Project of Jiangsu Social Science Foundation"Structural Characteristics of National Income Distribution in Jiangsu Province and Poli-cies and Countermeasures for Narrowing Urban and Rural Income Gap"(12EYC013)
文摘Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland circulation from supply and demand of land.Results showed that non-agricultural employment,social security level,and regional economic development level are key factors.In view of these factors,it is recommended to improve rural labor quality,establish perfect rural social security system,and constantly improve rural security level,which are fundamental ways to promoting farmland circulation and improve circulation market.
