The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement pr...The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement principle for the motor is proved by experiments. The pulse waveforms are applied to drive the motor to move in steps. The motor has a displacement resolution of 10 nm and a maximum velocity of 0.6 mm/s. It can drive a 200 g slider whose range is 20 mm. A one-dimensional precision positioning platform is fabricated by using the new hybrid piezoelectric motor. The prototype is made up of two servomotors and two piezoelectric motors, which are controlled automatically by a computer. The positioning range of the platform is 10 cm.展开更多
This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors ...This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors which exist in our smartphones such as accelerometer, gyroscope, magnetometer etc. to track the position for painting in virtual reality, like Google Tilt Brush, but cost effectively. Research studies till date on estimating position and localization and tracking have been thoroughly reviewed to find the appropriate algorithm which will provide accurate result with minimum drift error. Sensor fusion, Inertial Measurement Unit (IMU), MEMS inertial sensor, Kalman filter based global translational localization systems are studied. It is observed, prevailing approaches consist issues such as stability, random bias drift, noisy acceleration output, position estimation error, robustness or accuracy, cost effectiveness etc. Moreover, issues with motions that do not follow laws of physics, bandwidth, restrictive nature of assumptions, scale optimization for large space are noticed as well. Advantages of such smartphone sensor based position estimation approaches include, less memory demand, very fast operation, making them well suited for real time problems and embedded systems. Being independent of the size of the system, they can work effectively for high dimensional systems as well. Through study of these approaches it is observed, extended Kalman filter gives the highest accuracy with reduced requirement of excess hardware during tracking. It renders better and faster result when used in accelerometer sensor. With the aid of various software, error accuracy can be increased further as well.展开更多
In this study it is demonstrated that oxygen-plasma-generated CuOx can enhance the holes injection from ITO anode into polymer layer in single-layer polymer EL devices. The possible reason for this enhancement is beca...In this study it is demonstrated that oxygen-plasma-generated CuOx can enhance the holes injection from ITO anode into polymer layer in single-layer polymer EL devices. The possible reason for this enhancement is because the ITO anode modified with CuOx possesses much higher work function than pure ITO anode, which reduces the barrier for hole-injection and further lowers the operational voltage of the polymer EL devices. The work function shift is probable due to the oxygen-plasma-generated CuOx can store more releasable oxygen, and the releasable oxygen in turn changes the oxygen concentration just near ITO surface, which will shift the work function of ITO anode.展开更多
AIM: To assess the efficacy and safety of a patientpositioning device(EZ-FIX) for endoscopic retrograde cholangiopancreatography(ERCP).METHODS: A total of 105 patients were randomized to the EZ-FIX(n = 53) or non-EZ-F...AIM: To assess the efficacy and safety of a patientpositioning device(EZ-FIX) for endoscopic retrograde cholangiopancreatography(ERCP).METHODS: A total of 105 patients were randomized to the EZ-FIX(n = 53) or non-EZ-FIX(n = 52) group in this prospective study. Midazolam and propofol,titrated to provide an adequate level of sedation during therapeutic ERCP, were administered by trained registered nurses under endoscopist supervision.Primary outcome measures were the total dose of propofol and sedative-related complications, including hypoxia and hypotension. Secondary outcome measures were recovery time and sedation satisfaction of the endoscopist, nurses, and patients.RESULTS: There was no significant difference in the rate of hypoxia, but there was a statistical trend(EX-FIX group; n = 4, 7.55%, control group; n = 6, 11.53%,P = 0.06). The mean total dose of propofol was lower in the EZ-FIX group than in the non-EZ-FIX group(89.43 ± 49.8 mg vs 112.4 ± 53.8 mg, P = 0.025).In addition, the EZ-FIX group had a shorter mean recovery time(11.23 ± 4.61 mg vs 14.96 ± 5.12 mg, P< 0.001). Sedation satisfaction of the endoscopist and nurses was higher in the EX.FIX group than in the nonEZ-FIX group. Technical success rates of the procedure were 96.23% and 96.15%, respectively(P = 0.856).Procedure-related complications did not differ by group(11.32% vs 13.46%, respectively, P = 0.735).CONCLUSION: Using EZ-FIX reduced the total dose of propofol and the recovery time, and increased the satisfaction of the endoscopist and nurses.展开更多
Vehicular Ad-Hoc Networks (VANET) is a research venue that promises for many useful applications. Most of these applications require a precise real-time positioning system for each vehicle. However, practically the ex...Vehicular Ad-Hoc Networks (VANET) is a research venue that promises for many useful applications. Most of these applications require a precise real-time positioning system for each vehicle. However, practically the existing tecniques are still not accurate and hence not suitable for some critical applications. In this paper, we will focus on the most critical ones which are the collision avoidance, and collision warning, or lane-tracking. Collision occurs when the distance between nearby vehicles decreases rapidly. Hence, an accurate and precise knowledge of the distance among each vehicle and all the surrounding vehicles has to be obtained to enable a realistic collision avoidance service. We propose to use the carbon nanotube network (CNT) integrated with other nano-devices that can provide accuracy in the order of millimeters. In this paper, theoretical investigations and mathematical formulations are presented. The obtained results show the effectiveness and accuracy of the proposed methodology.展开更多
Positive and negative pressures determine the performance of pneumatic precision metering device for rapeseed.In order to investigate the relationship between positive and negative pressures of nozzles,fluid models of...Positive and negative pressures determine the performance of pneumatic precision metering device for rapeseed.In order to investigate the relationship between positive and negative pressures of nozzles,fluid models of chamber were developed to simulate the airflow,and the k-εturbulence model was conducted to capture the pressure and velocity of nozzles.Through these efforts linear models were achieved.Meanwhile,the three-factor factorial split-split experiment was designed with negative pressure,positive pressure and the rotating speeds varying from-1000 to-4500 Pa,50 to 250 Pa and 10 to 45 r/min,respectively.The mathematical models were developed through employing the stepwise regression method.The sequence of influential factors on the quality of feed index was positive pressure,negative pressure and rotating speed.To obtain the match regulation of negative and positive pressures with“good”performance,the ratio coefficient K of negative and positive pressures was introduced to build mathematical models.Models relating ratio coefficient K with positive pressure were fitted in different rotating speeds.The results showed that the ratio coefficient was matchedГ∈[f1(x),f2(x)]from the fitting equations with the rotating speed of 10-30 r/min;while the rotating speed has greater influence when it was 35-40 r/min and the setsΛ∈[g1(x),g2(x)]were achieved,where x∈[100,250].This study could be conducted to adjust the rotating speed of the pneumatic system to optimize the ideal performance of the seeder.展开更多
The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are...The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are simulated by means of 2D Medici software for DC current gain and frequency characteristics. In addition, the simulated DC current gains and cut-off frequencies are compared at different collector-emitter bias voltages. Through the simulation results, both DC and HF device performance are found to be strongly impacted by degree of confinement of the neutral base in the SiGe layer, even in the absence of a conduction band barrier. This conclusion is of significance for designing and analyzing SiGe HBTs.展开更多
This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface ...This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface device while observing work of the robot with a video camera. We also investigate the effect of the proposed control by experiment. As cooperative work, we deal with work in which two robots carry an object together. The robot position control using force information finely adjusts the position of the robot arm to reduce the force applied to the object. Thus, the purpose of the control is to avoid large force so that the object is not broken. In our experiment, we make a comparison among the following three cases in order to clarify how to carry out the control effectively. In the first case, the two robots are operated manually by a user with his/her both hands. In the second case, one robot is operated manually by a user, and the other robot is moved automatically under the proposed control. In the last case, the object is carried directly by a human instead of the robot which is operated by the user in the second case. As a result, experimental results demonstrate that the control can help each system operated manually by the user to carry the object smoothly.展开更多
文摘The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement principle for the motor is proved by experiments. The pulse waveforms are applied to drive the motor to move in steps. The motor has a displacement resolution of 10 nm and a maximum velocity of 0.6 mm/s. It can drive a 200 g slider whose range is 20 mm. A one-dimensional precision positioning platform is fabricated by using the new hybrid piezoelectric motor. The prototype is made up of two servomotors and two piezoelectric motors, which are controlled automatically by a computer. The positioning range of the platform is 10 cm.
文摘This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors which exist in our smartphones such as accelerometer, gyroscope, magnetometer etc. to track the position for painting in virtual reality, like Google Tilt Brush, but cost effectively. Research studies till date on estimating position and localization and tracking have been thoroughly reviewed to find the appropriate algorithm which will provide accurate result with minimum drift error. Sensor fusion, Inertial Measurement Unit (IMU), MEMS inertial sensor, Kalman filter based global translational localization systems are studied. It is observed, prevailing approaches consist issues such as stability, random bias drift, noisy acceleration output, position estimation error, robustness or accuracy, cost effectiveness etc. Moreover, issues with motions that do not follow laws of physics, bandwidth, restrictive nature of assumptions, scale optimization for large space are noticed as well. Advantages of such smartphone sensor based position estimation approaches include, less memory demand, very fast operation, making them well suited for real time problems and embedded systems. Being independent of the size of the system, they can work effectively for high dimensional systems as well. Through study of these approaches it is observed, extended Kalman filter gives the highest accuracy with reduced requirement of excess hardware during tracking. It renders better and faster result when used in accelerometer sensor. With the aid of various software, error accuracy can be increased further as well.
文摘In this study it is demonstrated that oxygen-plasma-generated CuOx can enhance the holes injection from ITO anode into polymer layer in single-layer polymer EL devices. The possible reason for this enhancement is because the ITO anode modified with CuOx possesses much higher work function than pure ITO anode, which reduces the barrier for hole-injection and further lowers the operational voltage of the polymer EL devices. The work function shift is probable due to the oxygen-plasma-generated CuOx can store more releasable oxygen, and the releasable oxygen in turn changes the oxygen concentration just near ITO surface, which will shift the work function of ITO anode.
基金Supported by Korea Healthcare Technology R and D Project,Ministry of Health and Welfare,South Korea(A100054)
文摘AIM: To assess the efficacy and safety of a patientpositioning device(EZ-FIX) for endoscopic retrograde cholangiopancreatography(ERCP).METHODS: A total of 105 patients were randomized to the EZ-FIX(n = 53) or non-EZ-FIX(n = 52) group in this prospective study. Midazolam and propofol,titrated to provide an adequate level of sedation during therapeutic ERCP, were administered by trained registered nurses under endoscopist supervision.Primary outcome measures were the total dose of propofol and sedative-related complications, including hypoxia and hypotension. Secondary outcome measures were recovery time and sedation satisfaction of the endoscopist, nurses, and patients.RESULTS: There was no significant difference in the rate of hypoxia, but there was a statistical trend(EX-FIX group; n = 4, 7.55%, control group; n = 6, 11.53%,P = 0.06). The mean total dose of propofol was lower in the EZ-FIX group than in the non-EZ-FIX group(89.43 ± 49.8 mg vs 112.4 ± 53.8 mg, P = 0.025).In addition, the EZ-FIX group had a shorter mean recovery time(11.23 ± 4.61 mg vs 14.96 ± 5.12 mg, P< 0.001). Sedation satisfaction of the endoscopist and nurses was higher in the EX.FIX group than in the nonEZ-FIX group. Technical success rates of the procedure were 96.23% and 96.15%, respectively(P = 0.856).Procedure-related complications did not differ by group(11.32% vs 13.46%, respectively, P = 0.735).CONCLUSION: Using EZ-FIX reduced the total dose of propofol and the recovery time, and increased the satisfaction of the endoscopist and nurses.
文摘Vehicular Ad-Hoc Networks (VANET) is a research venue that promises for many useful applications. Most of these applications require a precise real-time positioning system for each vehicle. However, practically the existing tecniques are still not accurate and hence not suitable for some critical applications. In this paper, we will focus on the most critical ones which are the collision avoidance, and collision warning, or lane-tracking. Collision occurs when the distance between nearby vehicles decreases rapidly. Hence, an accurate and precise knowledge of the distance among each vehicle and all the surrounding vehicles has to be obtained to enable a realistic collision avoidance service. We propose to use the carbon nanotube network (CNT) integrated with other nano-devices that can provide accuracy in the order of millimeters. In this paper, theoretical investigations and mathematical formulations are presented. The obtained results show the effectiveness and accuracy of the proposed methodology.
基金The research was funded by the National Science Foundation of China under grant 51275197National Rapeseed Industrial System Special Foundation CARS-13,National Science and Technology Support Project 013BAD08B02and High School Science Research Foundation 2014PY033.
文摘Positive and negative pressures determine the performance of pneumatic precision metering device for rapeseed.In order to investigate the relationship between positive and negative pressures of nozzles,fluid models of chamber were developed to simulate the airflow,and the k-εturbulence model was conducted to capture the pressure and velocity of nozzles.Through these efforts linear models were achieved.Meanwhile,the three-factor factorial split-split experiment was designed with negative pressure,positive pressure and the rotating speeds varying from-1000 to-4500 Pa,50 to 250 Pa and 10 to 45 r/min,respectively.The mathematical models were developed through employing the stepwise regression method.The sequence of influential factors on the quality of feed index was positive pressure,negative pressure and rotating speed.To obtain the match regulation of negative and positive pressures with“good”performance,the ratio coefficient K of negative and positive pressures was introduced to build mathematical models.Models relating ratio coefficient K with positive pressure were fitted in different rotating speeds.The results showed that the ratio coefficient was matchedГ∈[f1(x),f2(x)]from the fitting equations with the rotating speed of 10-30 r/min;while the rotating speed has greater influence when it was 35-40 r/min and the setsΛ∈[g1(x),g2(x)]were achieved,where x∈[100,250].This study could be conducted to adjust the rotating speed of the pneumatic system to optimize the ideal performance of the seeder.
文摘The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are simulated by means of 2D Medici software for DC current gain and frequency characteristics. In addition, the simulated DC current gains and cut-off frequencies are compared at different collector-emitter bias voltages. Through the simulation results, both DC and HF device performance are found to be strongly impacted by degree of confinement of the neutral base in the SiGe layer, even in the absence of a conduction band barrier. This conclusion is of significance for designing and analyzing SiGe HBTs.
文摘This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface device while observing work of the robot with a video camera. We also investigate the effect of the proposed control by experiment. As cooperative work, we deal with work in which two robots carry an object together. The robot position control using force information finely adjusts the position of the robot arm to reduce the force applied to the object. Thus, the purpose of the control is to avoid large force so that the object is not broken. In our experiment, we make a comparison among the following three cases in order to clarify how to carry out the control effectively. In the first case, the two robots are operated manually by a user with his/her both hands. In the second case, one robot is operated manually by a user, and the other robot is moved automatically under the proposed control. In the last case, the object is carried directly by a human instead of the robot which is operated by the user in the second case. As a result, experimental results demonstrate that the control can help each system operated manually by the user to carry the object smoothly.
