Financial market liquidity is a popular research topic.Investor-driven research uses the turnover rate to measure liquidity and generally finds that the higher the stock turnover rate,the lower the returns.However,the...Financial market liquidity is a popular research topic.Investor-driven research uses the turnover rate to measure liquidity and generally finds that the higher the stock turnover rate,the lower the returns.However,the traditional financial liquidity theory has been impacted by new machine-driven quantitative trading models.To explore high machine-driven liquidity and the impact of high turnover rates on returns,this study establishes a dual-market quantitative trading system,introduces a variational modal decomposition(VMD)-bidirectional gated recurrent unit(BiGRU)model for data prediction,and uses the back-end Hong Kong foreign exchange market to develop a quantitative trading strategy using the same rotating funds in the U.S.and Chinese stock markets.The experimental results show that given a principal amount of 210,000.00 CNY,the final predicted net return is 226,538.30 CNY,a net return of 107.86%,which is 40.6%higher than the net return of a single Chinese market.We conclude that,under machine-driven trading,increasing liquidity and turnover increase returns.This study provides a new perspective on liquidity theory that is useful for future financial market research and quantitative trading practices.展开更多
The effect of ultrasonic vibration on the dechromisation corrosion of a CuCr alloy in HC1 solution was studied and the corrosion mechanisms were analyzed. It is found that ultlasonic vibration reduces the dechromisati...The effect of ultrasonic vibration on the dechromisation corrosion of a CuCr alloy in HC1 solution was studied and the corrosion mechanisms were analyzed. It is found that ultlasonic vibration reduces the dechromisation incubation time, accelerates the dechromisafion corrosion rate, decreases the temperature and concentration of HC1 solution, and when the dechromisation occurs it seriously weakens the microstmcture of dechromisation layer. It is concluded that ultrasonic vibration can accelerate destruction of the passivation film on the Cr surface and increase the activities of Cl^- and Cr.展开更多
The performance model proposed by this study represents an innovative approach to deal with performance assessment in ATM （air traffic management）. It is based on Bayesian networks methodology, which presents severa...The performance model proposed by this study represents an innovative approach to deal with performance assessment in ATM （air traffic management）. It is based on Bayesian networks methodology, which presents several advantages but also some drawbacks as highlighted along the paper. We illustrate the main steps required for building the model and present a number of interesting results. The contribution of the paper is two-fold： （1） It presents a new methodological approach to deal with a problem which is of strategic importance for ANSPs （air navigation service providers）; （2） It provides insights on the interdependencies between factors influencing performance. Both results are considered particularly important nowadays, due to the SES （Single European Sky） performance scheme and its related target setting process.展开更多
Multi-objective optimization of crashworthiness in automobile front-end structure was performed,and finite element model(FEM)was validated by experimental results to ensure that FEM can predict the response value with...Multi-objective optimization of crashworthiness in automobile front-end structure was performed,and finite element model(FEM)was validated by experimental results to ensure that FEM can predict the response value with sufficient accuracy.Seven design variables and four crashworthiness indicators were defined.Through orthogonal design method,18 FEMs were established,and the response values of crashworthiness indicators were extracted.By using the variable-response specimen matrix,Kriging surrogate model(KSM)was constructed to replace FEM to refect the function correlation between variables and responses.The accuracy of KSM was also validated.Finally,the simulated annealing optimization algorithm was implemented in KSM to seek optimal and reliable solutions.Based on the optimal results and comparison analysis,the 9096-th iteration point was the optimal solution.Although the intrusion of firewall and the mass of optimal structure increased slightly,the vehicle acceleration of the optimal solution decreased by 6.9%,which fectively reduced the risk of occupant injury.展开更多
Uniqueness of landscaping projects was analyzed,and cost was regarded as an important index evaluating performance of landscaping construction enterprises. Based on reviewing limitation of cost control on landscaping ...Uniqueness of landscaping projects was analyzed,and cost was regarded as an important index evaluating performance of landscaping construction enterprises. Based on reviewing limitation of cost control on landscaping construction enterprises,enhancing construction management,controlling cost reasonably,and reducing project cost were proposed as the foundation and core content of enterprise cost management,and also the key to successful project management.By combining with design practices,suggestions for enhancing construction management of landscaping project,controlling cost and improving profits were given.展开更多
N, N, N′, N′-tetrakis-(2-benzimidazolylmethyl)-1, 2-ethanediamine(TBIMEDA), was prepared by reaction of ethylenediamine tetra-acetic acid disodium salt(EDTA) with 1, 2-diaminobenzene in a refluxed glycol solution, a...N, N, N′, N′-tetrakis-(2-benzimidazolylmethyl)-1, 2-ethanediamine(TBIMEDA), was prepared by reaction of ethylenediamine tetra-acetic acid disodium salt(EDTA) with 1, 2-diaminobenzene in a refluxed glycol solution, and furthermore, three allomeric complexes[(MIITBIMEDA) SO4·5H2O, M = Cd, Co, Ni] were selfassembled by solvothermal method based on reaction of this ligand with the relative sulfates respectively. These allomeric complexes were characterized by elemental analysis and IR spectroscopy and their crystal structures were determined by single crystal X-ray structural analysis. In the crystal architecture of these complexes, every metal(II) ion is chelated by one neutral TBIMEDA ligand to form an octahedral core with configuration of five heterocyclic rings (five- member ring). These cores then were linked to- gether by multi hydrogen bond interactions with sul- fate ions and water molecules to construct their 3D crystal architectures.展开更多
The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature...The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature stability and ability to resist quench heat and heat softening.After thermal-cold recycle at 560°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 57.5,its microstructure is mainly tempered martensite and a small amount of retained austenite,when thermal-cold recycled at 680°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 44.5,martensite in the hardfacing layer has almost decomposed.展开更多
Horticulture refers to the producing of horticultural plants in unsuitable season （cold or hot）, the use of keeping heat, preventing cold or keeping cool, rain facilities and equipment, to artificially create a suit...Horticulture refers to the producing of horticultural plants in unsuitable season （cold or hot）, the use of keeping heat, preventing cold or keeping cool, rain facilities and equipment, to artificially create a suitable micro climate horticultural crop growth environment, not or less affected by natural seasons conduct horticultural crop production, which is known as horticulture. It Simply covers facilities include a variety of hotbed, cooling bed, a small shed, shade avoidance, shade, shade cover, etc.; ordinary protection facilities usually refers to plastic greenhouses, plastic shed and Greenhouse; modem greenhouse, usually refers to capable of temperature and humidity, environmental conditions, fertilizer, gas and other automatic control of single buildings or greenhouse.展开更多
Perfluorinated acids(PFAs)are a new class of persistent organic pollutants that are difficult to defluorinate or remove.The reductive degradation of various representative PFAs in a biomimetic system composed of vitam...Perfluorinated acids(PFAs)are a new class of persistent organic pollutants that are difficult to defluorinate or remove.The reductive degradation of various representative PFAs in a biomimetic system composed of vitamin B_(12)(VB_(12))as a catalyst and nano-zero-valent iron-nickel bimetal(nFe^(0)/Ni^(0))as a reductant was investigated in this study.The effects of the self-structures of PFAs and the coexisting substances in natural water were also discussed.The results indicated that the defluorination and removal rates of PFAs were highly dependent on the length and terminal functional groups of the perfluorocarbon chain.Only Perfluorocarboxylates with C>11 and Perfluorosulfonates with C>6 were significantly degraded.Based on the analysis of the degradation products of perfluorobutanesulfonate(PFBS),perfluorohexanesulfonate(PFHxS),prefluorooctanesulfonate(PFOS),and 2-perfluoroctyl ethanol(8:2 FTOH),hydrolysis followed by the scission of C–S or C–C connecting the terminal functional groups was the dominant degradation pathway of long-chain PFAs instead of cleavage of C–C in the perfluorocarbon chain.The perfluorocarbon chain length affects the product type.It is speculated that the high bond dissociation energies of C–F bonds in short-chain PFAs hinder the occurrence of the decarboxylation-hydroxylation-elimination-hydrolysis(DHEH)pathway and make the addition of(–CF_(2)–)_(n) dominant.Meanwhile,the inhibition of SO_(4)^(2–)removal by PFOS was significant,whereas humic acid,Cl–,and dissolved oxygen had only a slight influence.Overall,this study provides new insights on the degradation of PFAs containing multiple structures and highlights the impact of the self-structure on PFAs removal.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.:72032006 and 92146005).
文摘Financial market liquidity is a popular research topic.Investor-driven research uses the turnover rate to measure liquidity and generally finds that the higher the stock turnover rate,the lower the returns.However,the traditional financial liquidity theory has been impacted by new machine-driven quantitative trading models.To explore high machine-driven liquidity and the impact of high turnover rates on returns,this study establishes a dual-market quantitative trading system,introduces a variational modal decomposition(VMD)-bidirectional gated recurrent unit(BiGRU)model for data prediction,and uses the back-end Hong Kong foreign exchange market to develop a quantitative trading strategy using the same rotating funds in the U.S.and Chinese stock markets.The experimental results show that given a principal amount of 210,000.00 CNY,the final predicted net return is 226,538.30 CNY,a net return of 107.86%,which is 40.6%higher than the net return of a single Chinese market.We conclude that,under machine-driven trading,increasing liquidity and turnover increase returns.This study provides a new perspective on liquidity theory that is useful for future financial market research and quantitative trading practices.
基金financially supported by the Scientific Research Fund of Heilongjiang Provincial Education Department, China (No. 11511020)
文摘The effect of ultrasonic vibration on the dechromisation corrosion of a CuCr alloy in HC1 solution was studied and the corrosion mechanisms were analyzed. It is found that ultlasonic vibration reduces the dechromisation incubation time, accelerates the dechromisafion corrosion rate, decreases the temperature and concentration of HC1 solution, and when the dechromisation occurs it seriously weakens the microstmcture of dechromisation layer. It is concluded that ultrasonic vibration can accelerate destruction of the passivation film on the Cr surface and increase the activities of Cl^- and Cr.
文摘The performance model proposed by this study represents an innovative approach to deal with performance assessment in ATM （air traffic management）. It is based on Bayesian networks methodology, which presents several advantages but also some drawbacks as highlighted along the paper. We illustrate the main steps required for building the model and present a number of interesting results. The contribution of the paper is two-fold： （1） It presents a new methodological approach to deal with a problem which is of strategic importance for ANSPs （air navigation service providers）; （2） It provides insights on the interdependencies between factors influencing performance. Both results are considered particularly important nowadays, due to the SES （Single European Sky） performance scheme and its related target setting process.
文摘Multi-objective optimization of crashworthiness in automobile front-end structure was performed,and finite element model(FEM)was validated by experimental results to ensure that FEM can predict the response value with sufficient accuracy.Seven design variables and four crashworthiness indicators were defined.Through orthogonal design method,18 FEMs were established,and the response values of crashworthiness indicators were extracted.By using the variable-response specimen matrix,Kriging surrogate model(KSM)was constructed to replace FEM to refect the function correlation between variables and responses.The accuracy of KSM was also validated.Finally,the simulated annealing optimization algorithm was implemented in KSM to seek optimal and reliable solutions.Based on the optimal results and comparison analysis,the 9096-th iteration point was the optimal solution.Although the intrusion of firewall and the mass of optimal structure increased slightly,the vehicle acceleration of the optimal solution decreased by 6.9%,which fectively reduced the risk of occupant injury.
文摘Uniqueness of landscaping projects was analyzed,and cost was regarded as an important index evaluating performance of landscaping construction enterprises. Based on reviewing limitation of cost control on landscaping construction enterprises,enhancing construction management,controlling cost reasonably,and reducing project cost were proposed as the foundation and core content of enterprise cost management,and also the key to successful project management.By combining with design practices,suggestions for enhancing construction management of landscaping project,controlling cost and improving profits were given.
文摘N, N, N′, N′-tetrakis-(2-benzimidazolylmethyl)-1, 2-ethanediamine(TBIMEDA), was prepared by reaction of ethylenediamine tetra-acetic acid disodium salt(EDTA) with 1, 2-diaminobenzene in a refluxed glycol solution, and furthermore, three allomeric complexes[(MIITBIMEDA) SO4·5H2O, M = Cd, Co, Ni] were selfassembled by solvothermal method based on reaction of this ligand with the relative sulfates respectively. These allomeric complexes were characterized by elemental analysis and IR spectroscopy and their crystal structures were determined by single crystal X-ray structural analysis. In the crystal architecture of these complexes, every metal(II) ion is chelated by one neutral TBIMEDA ligand to form an octahedral core with configuration of five heterocyclic rings (five- member ring). These cores then were linked to- gether by multi hydrogen bond interactions with sul- fate ions and water molecules to construct their 3D crystal architectures.
文摘The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature stability and ability to resist quench heat and heat softening.After thermal-cold recycle at 560°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 57.5,its microstructure is mainly tempered martensite and a small amount of retained austenite,when thermal-cold recycled at 680°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 44.5,martensite in the hardfacing layer has almost decomposed.
文摘Horticulture refers to the producing of horticultural plants in unsuitable season （cold or hot）, the use of keeping heat, preventing cold or keeping cool, rain facilities and equipment, to artificially create a suitable micro climate horticultural crop growth environment, not or less affected by natural seasons conduct horticultural crop production, which is known as horticulture. It Simply covers facilities include a variety of hotbed, cooling bed, a small shed, shade avoidance, shade, shade cover, etc.; ordinary protection facilities usually refers to plastic greenhouses, plastic shed and Greenhouse; modem greenhouse, usually refers to capable of temperature and humidity, environmental conditions, fertilizer, gas and other automatic control of single buildings or greenhouse.
基金supported by the National Natural Science Foundation of China(No.51878300)the Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University(No.ZQN-YX602)+1 种基金the Science and Technology Program of Quanzhou City(No.2018C084R)the Experimental Teaching and Management Reform Project of Huaqiao University in 2023(No.SY2023J03).
文摘Perfluorinated acids(PFAs)are a new class of persistent organic pollutants that are difficult to defluorinate or remove.The reductive degradation of various representative PFAs in a biomimetic system composed of vitamin B_(12)(VB_(12))as a catalyst and nano-zero-valent iron-nickel bimetal(nFe^(0)/Ni^(0))as a reductant was investigated in this study.The effects of the self-structures of PFAs and the coexisting substances in natural water were also discussed.The results indicated that the defluorination and removal rates of PFAs were highly dependent on the length and terminal functional groups of the perfluorocarbon chain.Only Perfluorocarboxylates with C>11 and Perfluorosulfonates with C>6 were significantly degraded.Based on the analysis of the degradation products of perfluorobutanesulfonate(PFBS),perfluorohexanesulfonate(PFHxS),prefluorooctanesulfonate(PFOS),and 2-perfluoroctyl ethanol(8:2 FTOH),hydrolysis followed by the scission of C–S or C–C connecting the terminal functional groups was the dominant degradation pathway of long-chain PFAs instead of cleavage of C–C in the perfluorocarbon chain.The perfluorocarbon chain length affects the product type.It is speculated that the high bond dissociation energies of C–F bonds in short-chain PFAs hinder the occurrence of the decarboxylation-hydroxylation-elimination-hydrolysis(DHEH)pathway and make the addition of(–CF_(2)–)_(n) dominant.Meanwhile,the inhibition of SO_(4)^(2–)removal by PFOS was significant,whereas humic acid,Cl–,and dissolved oxygen had only a slight influence.Overall,this study provides new insights on the degradation of PFAs containing multiple structures and highlights the impact of the self-structure on PFAs removal.
