In recent years, digital investment portfolios have become a significant area of interest in the field of machine learning. To tackle the issue of neglecting the momentum effect in risk asset prices within the follow-...In recent years, digital investment portfolios have become a significant area of interest in the field of machine learning. To tackle the issue of neglecting the momentum effect in risk asset prices within the follow-the-winner strategy and to evaluate the significance of this effect, a novel measure of risk asset price momentum trend is introduced for online investment portfolio research. Firstly, a novel approach is introduced to quantify the momentum trend effect, which is determined by the product of the slope of the linear regression model and the absolute value of the linear correlation coefficient. Secondly, a new investment portfolio optimization problem is established based on the prediction of future returns. Thirdly, the Lagrange multiplier method is used to obtain the analytical solution of the optimization model, and the soft projection optimization algorithm is used to map the analytical solution to obtain the investment portfolio of the model. Finally, experiments are conducted on five benchmark datasets and compared with popular investment portfolio algorithms. The empirical findings indicate that the algorithm we are introduced is capable of generating higher investment returns, thereby establishing its efficacy for the management of the online investment portfolios.展开更多
The quality of Radix saposhnikoviae(RS) had deteriorated due to the adoption of cultivated plants rather than wild plants. High temperature treatment increases the content of several chromones, however using one or ...The quality of Radix saposhnikoviae(RS) had deteriorated due to the adoption of cultivated plants rather than wild plants. High temperature treatment increases the content of several chromones, however using one or more individual constituents would be difficult to determine the medical quality of RS. In this paper, we used pharmacokinetic and pharmacologic approaches to evaluate the quality of RS. The active constituents were analysed using pharmacokinetic parameters of the chromone derivatives, and the antipyretic, analgesic, and anti-inflammatory effects were evaluated by pyretic animal model, hot plate test, and ear edema model, respectively. Only cimifugin was found in plasma after RS and heat-stress-RS were administered to rats, with a 50.6% increase in AUC0–24 h of cimifugin in the latter. Likewise, more potent anti-pyretic, analgesic, and anti-inflammatory activities were also found in the latter. Exposure of S. divaricata fresh roots to high temperatures enhanced the antipyretic, analgesic, and anti-inflammatory effects of RS by promoting the absorption of cimifugin.展开更多
In this paper, an underwater structure is modeled as a cylindrical shell with internal bulkheads, and closed by a truncated conical shell, and it consists of metal substrate and sound absorbing coating, whose FGM core...In this paper, an underwater structure is modeled as a cylindrical shell with internal bulkheads, and closed by a truncated conical shell, and it consists of metal substrate and sound absorbing coating, whose FGM core is considered. Suppose the inner cavity and outer space of the structure are filled with air and fluid mediums, the mechanical response of the underwater structure is calculated with Galerkin method while the acoustic response is investigated by means of the Helmholtz integral. Some numerical examples are given and the effect of geometrical size and material parameters on mechanical and acoustic response is discussed.展开更多
Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technol...Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technology,aiming at an overall time resolution of 80 ps for minimum-ionization particles to extend the K/πseparation(2σ)momentum range to 1.4 GeV/c.Methods The previous version of ETOF in BESIII consisted of plastic scintillators.The multi-hit events distort both shape and amplitude of the output signals.MRPC technique was chosen for the BESIII ETOF upgrade as it provides high time resolution and high detection efficiency,is of relatively low cost and is insensitive to neutral particles.Most importantly,the fine segmentation of the MRPC readout stripes can suppress multi-hit events effectively.Results The final design of MRPC module for ETOF is characterized by double-stack(2×6)structure,dual-end readout mode and precision electronics.To batch-produce and test these MRPC modules,a series of tools and production procedures as well as related performance simulation and test methods were developed.Results showed that each MRPC module’s intrinsic time resolution(including the electronics contribution)is around 50 ps and the efficiency is better than 97%.The overall performance of the upgraded ETOF is better than the designed index.The new ETOF has been successfully installed at BESIII and run in 2016.展开更多
文摘In recent years, digital investment portfolios have become a significant area of interest in the field of machine learning. To tackle the issue of neglecting the momentum effect in risk asset prices within the follow-the-winner strategy and to evaluate the significance of this effect, a novel measure of risk asset price momentum trend is introduced for online investment portfolio research. Firstly, a novel approach is introduced to quantify the momentum trend effect, which is determined by the product of the slope of the linear regression model and the absolute value of the linear correlation coefficient. Secondly, a new investment portfolio optimization problem is established based on the prediction of future returns. Thirdly, the Lagrange multiplier method is used to obtain the analytical solution of the optimization model, and the soft projection optimization algorithm is used to map the analytical solution to obtain the investment portfolio of the model. Finally, experiments are conducted on five benchmark datasets and compared with popular investment portfolio algorithms. The empirical findings indicate that the algorithm we are introduced is capable of generating higher investment returns, thereby establishing its efficacy for the management of the online investment portfolios.
基金National Natural Science Foundation of China(Gr ant No.81541079)Natural Science Foundation of Heilongjiang province(Grant No.H2017065)the Doctoral Scientific Research Fou ndation of Liaoning Province(Grant No.20170520132)
文摘The quality of Radix saposhnikoviae(RS) had deteriorated due to the adoption of cultivated plants rather than wild plants. High temperature treatment increases the content of several chromones, however using one or more individual constituents would be difficult to determine the medical quality of RS. In this paper, we used pharmacokinetic and pharmacologic approaches to evaluate the quality of RS. The active constituents were analysed using pharmacokinetic parameters of the chromone derivatives, and the antipyretic, analgesic, and anti-inflammatory effects were evaluated by pyretic animal model, hot plate test, and ear edema model, respectively. Only cimifugin was found in plasma after RS and heat-stress-RS were administered to rats, with a 50.6% increase in AUC0–24 h of cimifugin in the latter. Likewise, more potent anti-pyretic, analgesic, and anti-inflammatory activities were also found in the latter. Exposure of S. divaricata fresh roots to high temperatures enhanced the antipyretic, analgesic, and anti-inflammatory effects of RS by promoting the absorption of cimifugin.
基金supported by the National Natural Science Foundation of China(No.11372105)the New Century Excellent Talents Program in University(No.NCET-13-0184)
文摘In this paper, an underwater structure is modeled as a cylindrical shell with internal bulkheads, and closed by a truncated conical shell, and it consists of metal substrate and sound absorbing coating, whose FGM core is considered. Suppose the inner cavity and outer space of the structure are filled with air and fluid mediums, the mechanical response of the underwater structure is calculated with Galerkin method while the acoustic response is investigated by means of the Helmholtz integral. Some numerical examples are given and the effect of geometrical size and material parameters on mechanical and acoustic response is discussed.
基金supported by the National Natural Science Foundation of China(Nos.10979003,11675172,U1232206)Chinese Academy of Sciences(No.1G201331231172010).
文摘Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technology,aiming at an overall time resolution of 80 ps for minimum-ionization particles to extend the K/πseparation(2σ)momentum range to 1.4 GeV/c.Methods The previous version of ETOF in BESIII consisted of plastic scintillators.The multi-hit events distort both shape and amplitude of the output signals.MRPC technique was chosen for the BESIII ETOF upgrade as it provides high time resolution and high detection efficiency,is of relatively low cost and is insensitive to neutral particles.Most importantly,the fine segmentation of the MRPC readout stripes can suppress multi-hit events effectively.Results The final design of MRPC module for ETOF is characterized by double-stack(2×6)structure,dual-end readout mode and precision electronics.To batch-produce and test these MRPC modules,a series of tools and production procedures as well as related performance simulation and test methods were developed.Results showed that each MRPC module’s intrinsic time resolution(including the electronics contribution)is around 50 ps and the efficiency is better than 97%.The overall performance of the upgraded ETOF is better than the designed index.The new ETOF has been successfully installed at BESIII and run in 2016.