In this paper, a multi-sensory quality evaluation using an array of instruments to measure different sensory qualities is established via communication network. The network is used to transmit quality data to evaluati...In this paper, a multi-sensory quality evaluation using an array of instruments to measure different sensory qualities is established via communication network. The network is used to transmit quality data to evaluation computer. And the network-induced delays between instruments and computer may have negative influence on final evaluation results. The main goal of this paper is to analyze network delays’ influence on evaluation results, and present a fuzzy-logic based solution to eliminate the impact and improve the precision of evaluation. And simulations are conducted to show the effectiveness of the proposed approach.展开更多
The thermal upgrading of two residual oils tory-scale continuous delayed coking unit. The goal with different characteristics was studied in a labora- was to investigate the influence of the process vari- ables such a...The thermal upgrading of two residual oils tory-scale continuous delayed coking unit. The goal with different characteristics was studied in a labora- was to investigate the influence of the process vari- ables such as temperature, reaction time and additive on liquid yield and products distribution. A maximum liquid yield of 73% was achieved compared to 69% with the commercial unit. This yield was even increased to 75% under the effect of an additive. The fractionation of liquid oil by simulated vacuum distillation showed a high yield of diesel （46.9%）, compared to 28% for the commercial unit.展开更多
The current technology for producing the petroleum needle coke is apt to cause overflow of feedstock from the coke drums, instability in operation of coking unit, low mechanical strength of petroleum coke, and high pe...The current technology for producing the petroleum needle coke is apt to cause overflow of feedstock from the coke drums, instability in operation of coking unit, low mechanical strength of petroleum coke, and high percentage of coke powder, leading to difficulties in improving the overall quality of needle coke. Therefore, we have developed a new technology for producing the needle coke,featuring the manipulation of temperature range in a narrow scale at high pressure coupled with feedstock alternations. This new kind of technology has been successfully applied in a 60kt/a commercial coking unit. Provided that demand for the feedstock quality is satisfied, petroleum needle coke meeting the international quality standard can be manufactured using RIPP's technology for producing petroleum needle coke.展开更多
This paper presents a novel precision delay circuit design for high-speed data acquisition systems. Many studies have suggested that various advanced electronic measurement apparatuses require that the delay circuit s...This paper presents a novel precision delay circuit design for high-speed data acquisition systems. Many studies have suggested that various advanced electronic measurement apparatuses require that the delay circuit should have a high precision and a short delay interval. Practically, however, such measurement apparatuses are low in preci- sion and long in delay interval at present. The structure and function of a data acquisition system is introduced first; then the principle of ramp-based precision delay circuits and the digitally programmable delay generator is studied and the precision delay circuit is designed. The authors also demonstrated 8-bit programmable delay circuits with a timing pre- cision of 10 ps. Therefore the programmable precision delay circuit here presented has a higher precision, shorter inter- val and more detectable function than any other precision delay circuit.展开更多
A dynamical model for toxin producing phytoplankton and zooplankton has been formu- lated and analyzed. Due to gestation of prey, a discrete time delay is incorporated in the predator dynamics. The stability of the de...A dynamical model for toxin producing phytoplankton and zooplankton has been formu- lated and analyzed. Due to gestation of prey, a discrete time delay is incorporated in the predator dynamics. The stability of the delay model is discussed and Hopf bifurcation to a periodic orbit is established. Stability and direction of bifurcating periodic orbits are investigated using normal form theory and center manifold arguments. Global existence of periodic orbits is also established. To substantiate analytical findings, numerical simu- lations are performed. The system shows rich dynamic behavior including chaos and limit cycles. The influence of seasonality in intrinsic growth parameter of the phytoplankton population is also investigated. Seasonality leads to complexity in the system.展开更多
基金partially supported by National Natural Science Foundation of China,Project No.60274031International Cooperation Project of Science&Technology Commission of Shanghai Municipality,Project No.015107017Building Fund for Doctoral Disciplines of Shanghai Mouicipality
文摘In this paper, a multi-sensory quality evaluation using an array of instruments to measure different sensory qualities is established via communication network. The network is used to transmit quality data to evaluation computer. And the network-induced delays between instruments and computer may have negative influence on final evaluation results. The main goal of this paper is to analyze network delays’ influence on evaluation results, and present a fuzzy-logic based solution to eliminate the impact and improve the precision of evaluation. And simulations are conducted to show the effectiveness of the proposed approach.
文摘The thermal upgrading of two residual oils tory-scale continuous delayed coking unit. The goal with different characteristics was studied in a labora- was to investigate the influence of the process vari- ables such as temperature, reaction time and additive on liquid yield and products distribution. A maximum liquid yield of 73% was achieved compared to 69% with the commercial unit. This yield was even increased to 75% under the effect of an additive. The fractionation of liquid oil by simulated vacuum distillation showed a high yield of diesel （46.9%）, compared to 28% for the commercial unit.
文摘The current technology for producing the petroleum needle coke is apt to cause overflow of feedstock from the coke drums, instability in operation of coking unit, low mechanical strength of petroleum coke, and high percentage of coke powder, leading to difficulties in improving the overall quality of needle coke. Therefore, we have developed a new technology for producing the needle coke,featuring the manipulation of temperature range in a narrow scale at high pressure coupled with feedstock alternations. This new kind of technology has been successfully applied in a 60kt/a commercial coking unit. Provided that demand for the feedstock quality is satisfied, petroleum needle coke meeting the international quality standard can be manufactured using RIPP's technology for producing petroleum needle coke.
文摘This paper presents a novel precision delay circuit design for high-speed data acquisition systems. Many studies have suggested that various advanced electronic measurement apparatuses require that the delay circuit should have a high precision and a short delay interval. Practically, however, such measurement apparatuses are low in preci- sion and long in delay interval at present. The structure and function of a data acquisition system is introduced first; then the principle of ramp-based precision delay circuits and the digitally programmable delay generator is studied and the precision delay circuit is designed. The authors also demonstrated 8-bit programmable delay circuits with a timing pre- cision of 10 ps. Therefore the programmable precision delay circuit here presented has a higher precision, shorter inter- val and more detectable function than any other precision delay circuit.
文摘A dynamical model for toxin producing phytoplankton and zooplankton has been formu- lated and analyzed. Due to gestation of prey, a discrete time delay is incorporated in the predator dynamics. The stability of the delay model is discussed and Hopf bifurcation to a periodic orbit is established. Stability and direction of bifurcating periodic orbits are investigated using normal form theory and center manifold arguments. Global existence of periodic orbits is also established. To substantiate analytical findings, numerical simu- lations are performed. The system shows rich dynamic behavior including chaos and limit cycles. The influence of seasonality in intrinsic growth parameter of the phytoplankton population is also investigated. Seasonality leads to complexity in the system.
