Cluster tools have advantages of shorter cycle times,faster process development,and better yield for less contamination.The sequence of dual-arm cluster tools is a complex logistics process during the semiconductor pr...Cluster tools have advantages of shorter cycle times,faster process development,and better yield for less contamination.The sequence of dual-arm cluster tools is a complex logistics process during the semiconductor production.Efficient use of cluster tools is naturally very significant to competitive fab operations.Generating an optimized sequence in a computationally efficient manner and assessing the quality of the requirements to improve the fab production are the key factors for semiconductor manufacturing productivity.The Petri net modeling is introduced to minimize the makespan of the process for the three different logical modes and select a better mode after comparing the makespan among the three logical modes.The tool sequence optimization problem is formulated as optimization firing transition sequences based on the Petri net and then the formulation is converted to be linearly solved by the branch-and-cut method in the standard commercial solver CPLEX.Special methods for the linear conversion are highlighted.Due to the limited calculation time requirement for the real production and the large scale of the problem,special methods for the efficiency tuning are applied according to the characteristics of the problem.Numerical testing is supported by one of the most advanced semiconductor enterprises and the computational results show significant improvement compared with the traditional manual sequence results.展开更多
In this study an indirect adaptive sliding mode control (SMC) based on a fuzzy logic scheme is proposed to strengthen the tracking control performance of a general class of multi-input multi-output (MIMO) nonlinear un...In this study an indirect adaptive sliding mode control (SMC) based on a fuzzy logic scheme is proposed to strengthen the tracking control performance of a general class of multi-input multi-output (MIMO) nonlinear uncertain systems. Combining reaching law approach and fuzzy universal approximation theorem, the proposed design procedure combines the advantages of fuzzy logic control, adaptive control and sliding mode control. The stability of the control systems is proved in the sense of the Lyapunov second stability theorem. Two simulation studies are presented to demonstrate the effectiveness of our new hybrid control algorithm.展开更多
Now a days,MOS Current Mode Logic(MCML)has emerged as a better alternative to Complementary Metal Oxide Semiconductor(CMOS)logic in digital circuits.Recent works have only traditional logic gates that have issues with...Now a days,MOS Current Mode Logic(MCML)has emerged as a better alternative to Complementary Metal Oxide Semiconductor(CMOS)logic in digital circuits.Recent works have only traditional logic gates that have issues with information loss.Reversible logic is incorporated with MOS Current Mode Logic(MCML)in this proposed work to solve this problem,which is used for multiplier design,D Flip-Flop(DFF)and register.The minimization of power and area is the main aim of the work.In reversible logic,the count of outputs and inputs is retained as the same value for creating one-to-one mapping.A unique output vector set can be generated for each input vector set and information loss is also prevented.In reversible MCML based multiplier,reversible logic full adder is utilized to minimize the area and power.D flip-flops based on reversible MCML are often designed to store information that is then combined to form a reversible MCML based register.The proposed reversible MCML multiplier attains average power of 0.683 mW,Reversible MCML based DFF achieves 0.56μW and Reversible MCML based 8-bit register attains 04.04μW.The result shows that the proposed Reversible MCML based multiplier,Reversible MCML based D flip-flop and ReversibleMCML based register achieves better performance in terms of current,power dissipation,average power and area.展开更多
Dipole coupled nanomagnets controlled by the static Zeeman field can form various magnetic logic interconnects.However, the corner wire interconnect is often unreliable and error-prone at room temperature. In this stu...Dipole coupled nanomagnets controlled by the static Zeeman field can form various magnetic logic interconnects.However, the corner wire interconnect is often unreliable and error-prone at room temperature. In this study, we address this problem by making it into a reliable type with trapezoid-shaped nanomagnets, the shape anisotropy of which helps to offer the robustness. The building method of the proposed corner wire interconnect is discussed,and both its static and dynamic magnetization properties are investigated. Static micromagnetic simulation demonstrates that it can work correctly and reliably. Dynamic response results are reached by imposing an ac microwave field on the proposed corner wire. It is found that strong ferromagnetic resonance absorption appears at a low frequency. With the help of a very small ac field with the peak resonance frequency, the required static Zeeman field to switch the corner wire is significantly decreased by ~21 m T. This novel interconnect would pave the way for the realization of reliable and low power nanomagnetic logic circuits.展开更多
This paper investigates the issue of testing Current Mode Logic (CML) gates. A three-bit parity checker is used as a case study. It is first shown that, as expected, the stuck-at fault model is not appropriate for tes...This paper investigates the issue of testing Current Mode Logic (CML) gates. A three-bit parity checker is used as a case study. It is first shown that, as expected, the stuck-at fault model is not appropriate for testing CML gates. It is then proved that switching the order in which inputs are applied to a gate will affect the minimum test set;this is not the case in conventional voltage mode gates. Both the circuit output and its inverse have to be monitored to reduce the size of the test set.展开更多
In the context of induction motor control, there are various control strategies used to separately control torque and flux. One common approach is known as Field-Oriented Control (FOC). This technique involves transfo...In the context of induction motor control, there are various control strategies used to separately control torque and flux. One common approach is known as Field-Oriented Control (FOC). This technique involves transforming the three-phase currents and voltages into a rotating reference frame, commonly referred to as the “dq” frame. In this frame, the torque/speed and flux components are decoupled, allowing for independent control, by doing so, the motor’s speed can be regulated accurately and maintain a constant flux which is crucial to ensure optimal motor performance and efficiency. The research focused on studying and simulating a field-oriented control system using fuzzy control techniques for an induction motor. The aim was to address the issue of parameter variations, particularly the change in rotor resistance during motor operation, which causes the control system to deviate from the desired direction. This deviation implies to an increase in the magnetic flux value, specifically the flux component on the q-axis. By employing fuzzy logic techniques to regulate flux vector’s components in the dq frame, this problem was successfully resolved, ensuring that the magnetic flux value remains within the nominal limits. To enhance the control system’s performance, response speed, and efficiency of the motor, sliding mode controllers were implemented to regulate the current in the inner loop. The simulation results demonstrated the proficiency of the proposed methodology.展开更多
This research presents a methodology,to calculate the amount of physical activity during the transportation.It contains the following steps:(1)trip and activity detection(2)speed calculation(3)splitting trips into tri...This research presents a methodology,to calculate the amount of physical activity during the transportation.It contains the following steps:(1)trip and activity detection(2)speed calculation(3)splitting trips into trip-leg(4)transportation mode detection and(5)physical activity calculation.The Global Positioning System is used to record the transport activities,either single mode or multimode.During the trip execution,the travel behaviour and the travel mode are also observed to obtain the physical activity levels.The physical activity levels are calculated by taking the ratio of the Total Energy Expenditure and the Basal Metabolic Rate.To obtain the results,an automated system is presented which calculates the speed and also detects the mode of each trip-leg.It also calculates the amount of physical activity.The obtained physical activity levels for the recorded 1750 trips are unit less and range from 1.10 to 2.00.By using the motorized transportation mode,the physical activity levels stay low and the subject failed to achieve the recommended health guideline.The minimum value for the moderate level of physical activity is 1.6.The requirement can be fully achieved when the transportation mode is active i.e.walking,cycling,and performed at moderate intensity level for at least 30 min a day.展开更多
盘活利用闲置宅基地是深入实施乡村振兴战略、促进城乡融合发展的重要手段。文章借助制度分析与发展(Institutional Analysis and Development,IAD)框架,采用混合研究方法,以天津市宅基地制度改革试点区的3个村庄为研究对象,考察闲置宅...盘活利用闲置宅基地是深入实施乡村振兴战略、促进城乡融合发展的重要手段。文章借助制度分析与发展(Institutional Analysis and Development,IAD)框架,采用混合研究方法,以天津市宅基地制度改革试点区的3个村庄为研究对象,考察闲置宅基地盘活利用实践,从外部变量、行动舞台、交互作用及结果等3个方面揭示其盘活利用逻辑并比较其中差异,剖析影响模式选择的关键因素,旨在为不同类型村庄提供适配模式与案例参考。通过IAD框架揭示了闲置宅基地盘活利用的“环境—行动—结果”逻辑链条。基于天津市宅基地制度改革试点区3个村庄的案例比较总结了3种盘活模式的适用范围。研究表明,闲置宅基地盘活利用需“因地制宜、分类施策”,强化盘活主体协同,优化利益分配,以实现土地增效、集体增收与农民增益的共赢目标。展开更多
The construction of national parks is a strategic choice for safeguarding national ecological security and an urgent need for increasing the supply of high-quality ecological products.To sort out the basic logic and i...The construction of national parks is a strategic choice for safeguarding national ecological security and an urgent need for increasing the supply of high-quality ecological products.To sort out the basic logic and internal connections of the value realization of ecological products in national parks,this study puts forward the key elements and core mechanisms for the value realization of ecological products in national parks.Combining practical experience at home and abroad,the value realization modes of ecological products in national parks are divided into four major categories of national park ecological protection compensation,ecological right transaction,ecological capital income and ecological resource industrial operation,which are divided into 10 subcategories.Among the major categories,national park ecological protection compensation includes ecological compensation,transfer payment and ecological damage compensation;national park ecological right transaction includes payment for ecological services,pollution discharge rights and resource development rights;national park ecological capital income includes resource property right financing and compensation income financing;and national park ecological resource industrial operation includes industrial operation and franchised operation.The value realization of ecological products in national parks can be promoted by establishing and improving the national park ecological compensation mechanism and market-oriented mechanism,and by developing characteristic industries.展开更多
The aim of this paper is to develop a neuro-fuzzy-sliding mode controller （NFSMC） with a nonlinear sliding surface for a coupled tank system. The main purpose is to eliminate the chattering phenomenon and to overcom...The aim of this paper is to develop a neuro-fuzzy-sliding mode controller （NFSMC） with a nonlinear sliding surface for a coupled tank system. The main purpose is to eliminate the chattering phenomenon and to overcome the problem of the equivalent control computation. A first-order nonlinear sliding surface is presented, on which the developed sliding mode controller （SMC） is based. Mathematical proof for the stability and convergence of the system is presented. In order to reduce the chattering in SMC, a fixed boundary layer around the switch surface is used. Within the boundary layer, where the fuzzy logic control is applied, the chattering phenomenon, which is inherent in a sliding mode control, is avoided by smoothing the switch signal. Outside the boundary, the sliding mode control is applied to drive the system states into the boundary layer. Moreover, to compute the equivalent controller, a feed-forward neural network （NN） is used. The weights of the net are updated such that the corrective control term of the NFSMC goes to zero. Then, this NN also alleviates the chattering phenomenon because a big gain in the corrective control term produces a more serious chattering than a small gain. Experimental studies carried out on a coupled tank system indicate that the proposed approach is good for control applications.展开更多
基金the National Natural Science Foundation of China(No.60534010)the 111 Project (No.B08015)the Project of Ministry of Education (No.NCET-05-0294)
文摘Cluster tools have advantages of shorter cycle times,faster process development,and better yield for less contamination.The sequence of dual-arm cluster tools is a complex logistics process during the semiconductor production.Efficient use of cluster tools is naturally very significant to competitive fab operations.Generating an optimized sequence in a computationally efficient manner and assessing the quality of the requirements to improve the fab production are the key factors for semiconductor manufacturing productivity.The Petri net modeling is introduced to minimize the makespan of the process for the three different logical modes and select a better mode after comparing the makespan among the three logical modes.The tool sequence optimization problem is formulated as optimization firing transition sequences based on the Petri net and then the formulation is converted to be linearly solved by the branch-and-cut method in the standard commercial solver CPLEX.Special methods for the linear conversion are highlighted.Due to the limited calculation time requirement for the real production and the large scale of the problem,special methods for the efficiency tuning are applied according to the characteristics of the problem.Numerical testing is supported by one of the most advanced semiconductor enterprises and the computational results show significant improvement compared with the traditional manual sequence results.
文摘In this study an indirect adaptive sliding mode control (SMC) based on a fuzzy logic scheme is proposed to strengthen the tracking control performance of a general class of multi-input multi-output (MIMO) nonlinear uncertain systems. Combining reaching law approach and fuzzy universal approximation theorem, the proposed design procedure combines the advantages of fuzzy logic control, adaptive control and sliding mode control. The stability of the control systems is proved in the sense of the Lyapunov second stability theorem. Two simulation studies are presented to demonstrate the effectiveness of our new hybrid control algorithm.
文摘Now a days,MOS Current Mode Logic(MCML)has emerged as a better alternative to Complementary Metal Oxide Semiconductor(CMOS)logic in digital circuits.Recent works have only traditional logic gates that have issues with information loss.Reversible logic is incorporated with MOS Current Mode Logic(MCML)in this proposed work to solve this problem,which is used for multiplier design,D Flip-Flop(DFF)and register.The minimization of power and area is the main aim of the work.In reversible logic,the count of outputs and inputs is retained as the same value for creating one-to-one mapping.A unique output vector set can be generated for each input vector set and information loss is also prevented.In reversible MCML based multiplier,reversible logic full adder is utilized to minimize the area and power.D flip-flops based on reversible MCML are often designed to store information that is then combined to form a reversible MCML based register.The proposed reversible MCML multiplier attains average power of 0.683 mW,Reversible MCML based DFF achieves 0.56μW and Reversible MCML based 8-bit register attains 04.04μW.The result shows that the proposed Reversible MCML based multiplier,Reversible MCML based D flip-flop and ReversibleMCML based register achieves better performance in terms of current,power dissipation,average power and area.
基金Supported by the National Natural Science Foundation of China under Grant No 61302022
文摘Dipole coupled nanomagnets controlled by the static Zeeman field can form various magnetic logic interconnects.However, the corner wire interconnect is often unreliable and error-prone at room temperature. In this study, we address this problem by making it into a reliable type with trapezoid-shaped nanomagnets, the shape anisotropy of which helps to offer the robustness. The building method of the proposed corner wire interconnect is discussed,and both its static and dynamic magnetization properties are investigated. Static micromagnetic simulation demonstrates that it can work correctly and reliably. Dynamic response results are reached by imposing an ac microwave field on the proposed corner wire. It is found that strong ferromagnetic resonance absorption appears at a low frequency. With the help of a very small ac field with the peak resonance frequency, the required static Zeeman field to switch the corner wire is significantly decreased by ~21 m T. This novel interconnect would pave the way for the realization of reliable and low power nanomagnetic logic circuits.
文摘This paper investigates the issue of testing Current Mode Logic (CML) gates. A three-bit parity checker is used as a case study. It is first shown that, as expected, the stuck-at fault model is not appropriate for testing CML gates. It is then proved that switching the order in which inputs are applied to a gate will affect the minimum test set;this is not the case in conventional voltage mode gates. Both the circuit output and its inverse have to be monitored to reduce the size of the test set.
文摘In the context of induction motor control, there are various control strategies used to separately control torque and flux. One common approach is known as Field-Oriented Control (FOC). This technique involves transforming the three-phase currents and voltages into a rotating reference frame, commonly referred to as the “dq” frame. In this frame, the torque/speed and flux components are decoupled, allowing for independent control, by doing so, the motor’s speed can be regulated accurately and maintain a constant flux which is crucial to ensure optimal motor performance and efficiency. The research focused on studying and simulating a field-oriented control system using fuzzy control techniques for an induction motor. The aim was to address the issue of parameter variations, particularly the change in rotor resistance during motor operation, which causes the control system to deviate from the desired direction. This deviation implies to an increase in the magnetic flux value, specifically the flux component on the q-axis. By employing fuzzy logic techniques to regulate flux vector’s components in the dq frame, this problem was successfully resolved, ensuring that the magnetic flux value remains within the nominal limits. To enhance the control system’s performance, response speed, and efficiency of the motor, sliding mode controllers were implemented to regulate the current in the inner loop. The simulation results demonstrated the proficiency of the proposed methodology.
文摘This research presents a methodology,to calculate the amount of physical activity during the transportation.It contains the following steps:(1)trip and activity detection(2)speed calculation(3)splitting trips into trip-leg(4)transportation mode detection and(5)physical activity calculation.The Global Positioning System is used to record the transport activities,either single mode or multimode.During the trip execution,the travel behaviour and the travel mode are also observed to obtain the physical activity levels.The physical activity levels are calculated by taking the ratio of the Total Energy Expenditure and the Basal Metabolic Rate.To obtain the results,an automated system is presented which calculates the speed and also detects the mode of each trip-leg.It also calculates the amount of physical activity.The obtained physical activity levels for the recorded 1750 trips are unit less and range from 1.10 to 2.00.By using the motorized transportation mode,the physical activity levels stay low and the subject failed to achieve the recommended health guideline.The minimum value for the moderate level of physical activity is 1.6.The requirement can be fully achieved when the transportation mode is active i.e.walking,cycling,and performed at moderate intensity level for at least 30 min a day.
文摘盘活利用闲置宅基地是深入实施乡村振兴战略、促进城乡融合发展的重要手段。文章借助制度分析与发展(Institutional Analysis and Development,IAD)框架,采用混合研究方法,以天津市宅基地制度改革试点区的3个村庄为研究对象,考察闲置宅基地盘活利用实践,从外部变量、行动舞台、交互作用及结果等3个方面揭示其盘活利用逻辑并比较其中差异,剖析影响模式选择的关键因素,旨在为不同类型村庄提供适配模式与案例参考。通过IAD框架揭示了闲置宅基地盘活利用的“环境—行动—结果”逻辑链条。基于天津市宅基地制度改革试点区3个村庄的案例比较总结了3种盘活模式的适用范围。研究表明,闲置宅基地盘活利用需“因地制宜、分类施策”,强化盘活主体协同,优化利益分配,以实现土地增效、集体增收与农民增益的共赢目标。
基金The Major Project of the National Social Science Fund of China(24&ZD109)The Humanities and Social Sciences Fund of the Ministry of Education of China(23YJC630071)+1 种基金The Social Science Fund of Jiangxi Province(24GL46)The Open Fund of the Soft Science Research Cultivation Base of Jiangxi Province(GJJ190404)。
文摘The construction of national parks is a strategic choice for safeguarding national ecological security and an urgent need for increasing the supply of high-quality ecological products.To sort out the basic logic and internal connections of the value realization of ecological products in national parks,this study puts forward the key elements and core mechanisms for the value realization of ecological products in national parks.Combining practical experience at home and abroad,the value realization modes of ecological products in national parks are divided into four major categories of national park ecological protection compensation,ecological right transaction,ecological capital income and ecological resource industrial operation,which are divided into 10 subcategories.Among the major categories,national park ecological protection compensation includes ecological compensation,transfer payment and ecological damage compensation;national park ecological right transaction includes payment for ecological services,pollution discharge rights and resource development rights;national park ecological capital income includes resource property right financing and compensation income financing;and national park ecological resource industrial operation includes industrial operation and franchised operation.The value realization of ecological products in national parks can be promoted by establishing and improving the national park ecological compensation mechanism and market-oriented mechanism,and by developing characteristic industries.
文摘The aim of this paper is to develop a neuro-fuzzy-sliding mode controller （NFSMC） with a nonlinear sliding surface for a coupled tank system. The main purpose is to eliminate the chattering phenomenon and to overcome the problem of the equivalent control computation. A first-order nonlinear sliding surface is presented, on which the developed sliding mode controller （SMC） is based. Mathematical proof for the stability and convergence of the system is presented. In order to reduce the chattering in SMC, a fixed boundary layer around the switch surface is used. Within the boundary layer, where the fuzzy logic control is applied, the chattering phenomenon, which is inherent in a sliding mode control, is avoided by smoothing the switch signal. Outside the boundary, the sliding mode control is applied to drive the system states into the boundary layer. Moreover, to compute the equivalent controller, a feed-forward neural network （NN） is used. The weights of the net are updated such that the corrective control term of the NFSMC goes to zero. Then, this NN also alleviates the chattering phenomenon because a big gain in the corrective control term produces a more serious chattering than a small gain. Experimental studies carried out on a coupled tank system indicate that the proposed approach is good for control applications.
