A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe th...A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe the static and dynamic operations of the valves. Compared with a conventional E-type actuator, the proposed ε-type actuator reduced the moving mass weight by almost 65% without significant loss of solenoid force, and reduced the response time (RT) typically by 20%. Prototype valves were designed and fabricated based on the proposed ε-type actuator model. An experimental setup was also established to investigate the dynamic characteristics of valves. The experimental results of the dynamics of valves agreed well with simulations, indicating the validity of the FEA model.展开更多
We propose a new method to perform an ultra high speed all optical remote controlled X-NOR logic operation at a very long distance by exploiting the interaction of hypersecant optical soliton pulses (HOSP). To impleme...We propose a new method to perform an ultra high speed all optical remote controlled X-NOR logic operation at a very long distance by exploiting the interaction of hypersecant optical soliton pulses (HOSP). To implement such logic operation,three HOSPs maintaining a particular condition are introduced into an optical fiber where they interact with each other. Two of them carry the input of the logic operation with the constant triggering of other HOSP.展开更多
Ports operating in the same geographical range face significant competition among them. In such setting, less competitive ports may continually lose patronage of shippers （indigenous to them） to adjacent ones with b...Ports operating in the same geographical range face significant competition among them. In such setting, less competitive ports may continually lose patronage of shippers （indigenous to them） to adjacent ones with better attributes. The extent of and determinants of inter-port competition in the West Africa＇s coast are of interest to port administrators/operators who risk losing significant portion of their domestic generated cargo traffic to competing neighbouring ports. In this paper, we explore the question of what port specific attributes serve as competitive basis for West Africa＇s coastal ports operating in proximity to the other. Through a survey, users of these ports were asked to identify port specific attributes which they consider when deciding which port to use for shipments making. To enrich our empirical model, data collected from the survey were augmented with secondary data （on the identified attributes） obtained from the respective ports. Statistical evidence from data analysis suggests that ports operating in proximity in the West Africa＇s coast compete on the basis of attributes that minimise costs for port users, viz： ships＇ pre-berthiig time, ship turnround time, crane efficiency and availability of cargo spaces （proxied by frequency of ship calls）. Policy implications of the findings were discussed.展开更多
The paper presents the development and performance of a kinematics control scheme for the AGV based on inductive guidance in transporting newsprint rolls. The required error is pre-computed using a kinematics model of...The paper presents the development and performance of a kinematics control scheme for the AGV based on inductive guidance in transporting newsprint rolls. The required error is pre-computed using a kinematics model of the AGV taking into account the effect of various factors that contribute to improve tracking performance of the AGV. Simulation and experimental results illustrate that the kinematics model performs well and the results of various factors contribute to tracking performance of the AGV.展开更多
Autothermal reforming (ATR) is one of the leading methods for hydrogen production from hydrocar- bons. Liquefied petroleum gas, with propane as the main component, is a promising fuel for on-board hydrogen producing s...Autothermal reforming (ATR) is one of the leading methods for hydrogen production from hydrocar- bons. Liquefied petroleum gas, with propane as the main component, is a promising fuel for on-board hydrogen producing systems in fuel cell vehicles and for domestic fuel cell power generation devices. In this article, propane ATR process is studied and operation conditions are optimized with PRO/Ⅱ? from SIMSCI for proton exchange membrane fuel cell application. In the ATR system including water gas shift and preferential oxidation, heat in the hot streams and cold streams is controlled to be in balance. Different operation conditions are studied and drawn in contour plots. The region for ATR reforming with the highest efficiency can thus be identified. One operation point was chosen with the following process parameters: feed temperature for the ATR reactor is 425℃, steam to carbon ratio S/C is 2.08, air stoichiometry is 0.256. Thermal efficiency for the integrated system is calculated to be as high as 84.0 % with 38.27 % H2 and 3.2μl·L-1 CO in the product gas.展开更多
Here in this letter, we study the difference between quantum and classical deletion. We point out that the linear mapping deletion operation used in the impossibility proof for quantum systems applies also to classica...Here in this letter, we study the difference between quantum and classical deletion. We point out that the linear mapping deletion operation used in the impossibility proof for quantum systems applies also to classical system. The general classical deletion operation is a combined operation of measurement and transformation, i.e., first read the state and then transfer the state to the standard blank state. Though both quantum information and classical information can be deleted in an open system, quantum information cannot be recovered while classical information can be recovered.展开更多
This study proposes a theoretical quantum authenticated secure communication(QASC) protocol using Einstein-Podolsky-Rosen(EPR) entangle state,which enables a sender to send a secure as well as authenticated message to...This study proposes a theoretical quantum authenticated secure communication(QASC) protocol using Einstein-Podolsky-Rosen(EPR) entangle state,which enables a sender to send a secure as well as authenticated message to a receiver within only one step quantum transmission without having the classical channels and the certification authority.展开更多
For the Fischer-Tropsch synthesis （FrS）, this paper presents a numerical investigation in a 3D fiuidized bed reactor. The effect of the operation parameters such as bed temperature, superficial gas velocities, parti...For the Fischer-Tropsch synthesis （FrS）, this paper presents a numerical investigation in a 3D fiuidized bed reactor. The effect of the operation parameters such as bed temperature, superficial gas velocities, particle size and bed heights is discussed. A 3D-CFD model coupled with FTS chemical kinetics was set up. The computational resuits are compared with experimental data in terms of the components production rates, etc. The analysis shows that the bed heights, the bed temperature, the superficial gas velocities and particle sizes affect the C5 ＋ selectivity and the reaction rates. Product yields are dependent on the operating conditions especially the temperature.展开更多
We make comments on the conclusions of the paper:'Compare Quantum Operation Sensitivity for DifferentDistance Measures' [Commun.Theor.Phys.53 (2010)635],and give a physical example to describe the non-equivale...We make comments on the conclusions of the paper:'Compare Quantum Operation Sensitivity for DifferentDistance Measures' [Commun.Theor.Phys.53 (2010)635],and give a physical example to describe the non-equivalenceof the fidelity and the trace distance.We prove that the fidelity is not more sensitive to a quantum operation than thetrace distance.展开更多
An accurate method to solve the daynes Cummings （J-C） Hamiltonian has been investigated here. The phenomenon of atomic collapse and revival predicted by Jaynes-Cummings model is demonstrated. Solutions are consis- t...An accurate method to solve the daynes Cummings （J-C） Hamiltonian has been investigated here. The phenomenon of atomic collapse and revival predicted by Jaynes-Cummings model is demonstrated. Solutions are consis- tent with the precious such as using the operator method. Furthermore, the Jaynes-Cummings Hamiltonian including the anti-rotating term is also solved precisely using this accurate way so that results agree with experiments better. Essences of the anti-rotating term are revealed. We discuss the relations of the phenomenon of atomic collapse and revival with the average photons number, the light field phase angle, the resonant frequency, and the size of coupling constant. The discussions may make one select suitable conditions to carry out experiment well and study the virtual light field effect on cavity quantum electrodynamics.展开更多
基金Project supported by the Doctoral Fund of Ministry of Education of China (No. 20070335133)the Educational Commission of Zhejiang Province (No. 20070057), China
文摘A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe the static and dynamic operations of the valves. Compared with a conventional E-type actuator, the proposed ε-type actuator reduced the moving mass weight by almost 65% without significant loss of solenoid force, and reduced the response time (RT) typically by 20%. Prototype valves were designed and fabricated based on the proposed ε-type actuator model. An experimental setup was also established to investigate the dynamic characteristics of valves. The experimental results of the dynamics of valves agreed well with simulations, indicating the validity of the FEA model.
文摘We propose a new method to perform an ultra high speed all optical remote controlled X-NOR logic operation at a very long distance by exploiting the interaction of hypersecant optical soliton pulses (HOSP). To implement such logic operation,three HOSPs maintaining a particular condition are introduced into an optical fiber where they interact with each other. Two of them carry the input of the logic operation with the constant triggering of other HOSP.
文摘Ports operating in the same geographical range face significant competition among them. In such setting, less competitive ports may continually lose patronage of shippers （indigenous to them） to adjacent ones with better attributes. The extent of and determinants of inter-port competition in the West Africa＇s coast are of interest to port administrators/operators who risk losing significant portion of their domestic generated cargo traffic to competing neighbouring ports. In this paper, we explore the question of what port specific attributes serve as competitive basis for West Africa＇s coastal ports operating in proximity to the other. Through a survey, users of these ports were asked to identify port specific attributes which they consider when deciding which port to use for shipments making. To enrich our empirical model, data collected from the survey were augmented with secondary data （on the identified attributes） obtained from the respective ports. Statistical evidence from data analysis suggests that ports operating in proximity in the West Africa＇s coast compete on the basis of attributes that minimise costs for port users, viz： ships＇ pre-berthiig time, ship turnround time, crane efficiency and availability of cargo spaces （proxied by frequency of ship calls）. Policy implications of the findings were discussed.
文摘The paper presents the development and performance of a kinematics control scheme for the AGV based on inductive guidance in transporting newsprint rolls. The required error is pre-computed using a kinematics model of the AGV taking into account the effect of various factors that contribute to improve tracking performance of the AGV. Simulation and experimental results illustrate that the kinematics model performs well and the results of various factors contribute to tracking performance of the AGV.
基金Supported by the National 973 Program of China on Hydrogen Energy (TG2000026410) and International Cooperation Projecton Hydrogen Energy (2001AA515080).
文摘Autothermal reforming (ATR) is one of the leading methods for hydrogen production from hydrocar- bons. Liquefied petroleum gas, with propane as the main component, is a promising fuel for on-board hydrogen producing systems in fuel cell vehicles and for domestic fuel cell power generation devices. In this article, propane ATR process is studied and operation conditions are optimized with PRO/Ⅱ? from SIMSCI for proton exchange membrane fuel cell application. In the ATR system including water gas shift and preferential oxidation, heat in the hot streams and cold streams is controlled to be in balance. Different operation conditions are studied and drawn in contour plots. The region for ATR reforming with the highest efficiency can thus be identified. One operation point was chosen with the following process parameters: feed temperature for the ATR reactor is 425℃, steam to carbon ratio S/C is 2.08, air stoichiometry is 0.256. Thermal efficiency for the integrated system is calculated to be as high as 84.0 % with 38.27 % H2 and 3.2μl·L-1 CO in the product gas.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10775076 and 10874098the National Basic Research Program of China under Grant No. 2006CB921106the Specialized Research Fund for the Doctoral Program of Education Ministry of China under Grant No. 20060003048
文摘Here in this letter, we study the difference between quantum and classical deletion. We point out that the linear mapping deletion operation used in the impossibility proof for quantum systems applies also to classical system. The general classical deletion operation is a combined operation of measurement and transformation, i.e., first read the state and then transfer the state to the standard blank state. Though both quantum information and classical information can be deleted in an open system, quantum information cannot be recovered while classical information can be recovered.
文摘This study proposes a theoretical quantum authenticated secure communication(QASC) protocol using Einstein-Podolsky-Rosen(EPR) entangle state,which enables a sender to send a secure as well as authenticated message to a receiver within only one step quantum transmission without having the classical channels and the certification authority.
基金Supported by the National High-Tech R&D Program of China[2011AA05A204]the Fundamental Research Funds for the Central Universities[222201717013]
文摘For the Fischer-Tropsch synthesis （FrS）, this paper presents a numerical investigation in a 3D fiuidized bed reactor. The effect of the operation parameters such as bed temperature, superficial gas velocities, particle size and bed heights is discussed. A 3D-CFD model coupled with FTS chemical kinetics was set up. The computational resuits are compared with experimental data in terms of the components production rates, etc. The analysis shows that the bed heights, the bed temperature, the superficial gas velocities and particle sizes affect the C5 ＋ selectivity and the reaction rates. Product yields are dependent on the operating conditions especially the temperature.
基金Supported by the Natural Science Foundation of Shandong Province under Grant No. ZR2009AM019
文摘We make comments on the conclusions of the paper:'Compare Quantum Operation Sensitivity for DifferentDistance Measures' [Commun.Theor.Phys.53 (2010)635],and give a physical example to describe the non-equivalenceof the fidelity and the trace distance.We prove that the fidelity is not more sensitive to a quantum operation than thetrace distance.
基金Supported by the Natural Science Foundation of Hunan Province under Grant No.09JJ6011the Natural Science Foundation of Education Department of Hunan Province under Grant Nos.10A100 and 07C528
文摘An accurate method to solve the daynes Cummings （J-C） Hamiltonian has been investigated here. The phenomenon of atomic collapse and revival predicted by Jaynes-Cummings model is demonstrated. Solutions are consis- tent with the precious such as using the operator method. Furthermore, the Jaynes-Cummings Hamiltonian including the anti-rotating term is also solved precisely using this accurate way so that results agree with experiments better. Essences of the anti-rotating term are revealed. We discuss the relations of the phenomenon of atomic collapse and revival with the average photons number, the light field phase angle, the resonant frequency, and the size of coupling constant. The discussions may make one select suitable conditions to carry out experiment well and study the virtual light field effect on cavity quantum electrodynamics.
