The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and...The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio.展开更多
To ensure the safety of residents’lives and property by using automatic opening and closing of ordinary windows,this article designs an intelligent window automatic monitoring system.The article proposes a software a...To ensure the safety of residents’lives and property by using automatic opening and closing of ordinary windows,this article designs an intelligent window automatic monitoring system.The article proposes a software and hardware design scheme for the system,which comprises a microcontroller control module,temperature and humidity detection module,harmful gas detection module,rainfall detection module,human thermal radiation induction module,Organic Light-Emitting Diode(OLED)display module,stepper motor drive module,Wi-Fi communication module,etc.Users use this system to monitor environmental data such as temperature,humidity,rainfall,harmful gas concentrations,and human health.Users can control the opening and closing of windows through manual,microcontroller,and mobile application(app)remote methods,providing users with a more convenient,comfortable,and safe living environment.展开更多
Redundancy control can effectively enhance the stability and robustness of a system.Based on the conventional redundancy control switchover and majority arbitration strategy,this paper introduces the concept of hetero...Redundancy control can effectively enhance the stability and robustness of a system.Based on the conventional redundancy control switchover and majority arbitration strategy,this paper introduces the concept of heterogeneity and dynamics,constructs a dynamic heterogeneous redundancy-based microcontroller architecture DHR-MCU,and designs a fixed-leader distributed consensus algorithm that satisfies the program running state control of this architecture.The theoretical analysis and actual measurement of the prototype system prove that this architecture has good anti-attack and self-recovery capabilities under normal functions and performances and meets the general robust features in terms of safety and security.展开更多
Security is a serious concern, whether it may be the security of assets, data and human life. Providing humans with security and safety for their belongings and items is an important need. A smart lock door project/ w...Security is a serious concern, whether it may be the security of assets, data and human life. Providing humans with security and safety for their belongings and items is an important need. A smart lock door project/ with different types of methods for entry, like fingerprint and authentication PIN code is suggested with an unnoticeable face tracking camera capturing a photo in case of error data entry. It is to be controlled via the user’s smartphone using Blynk with the implementation of IoT. This technology is made with two microcontrollers. ESP32 is used to control the solenoid lock, fingerprint sensor and keypad. ESP32-CAM is used to capture a photo and send it to the owner’s smartphone to be viewed on Telegram application. Many conclusions are extracted from system results, as well as suggested ideas for future work.展开更多
By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the p...By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the programe of writing operation is given.展开更多
Demands for low-energy microcontrollers have been increasing in recent years. Since most microcontrollers achieve user programmability by integrating nonvolatile (NV) memories such as flash memories for storing their ...Demands for low-energy microcontrollers have been increasing in recent years. Since most microcontrollers achieve user programmability by integrating nonvolatile (NV) memories such as flash memories for storing their programs, the large power consumption required in accessing an NV memory has become a major problem. This problem becomes critical when the power supply voltage of NV microcontrollers is decreased. We can solve this problem by introducing an instruction cache, thus reducing the access frequency of the NV memory. Unlike general-purpose microprocessors, microcontrollers used for real-time applications in embedded systems must accurately calculate program execution time prior to its execution. Therefore, we introduce a “transparent” instruction cache, which does not change the existing NV microcontroller’s cycle-level execution time, for reducing power and energy consumption, but not for improving the processing speed. We have conducted detailed microar chitecture design based on the architecture of a major industrial microcontroller, and we evaluated power and energy consumption for several benchmark programs. Our evaluation shows that the proposed instruction cache can successfully reduce energy consumption in a fairly wide range of practical NV microcontroller configurations.展开更多
This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an ...This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an EasyPIC6 board and includes a PC-interfaced programmer for the PIC chip. It has many external modules: 128 × 64 graphic LCD display, 2 × 16 LCD display, 4 × 4 keypad, and port expander, all in the same bench. The trainer is capable of 36 experiments in logic/analogue electronic and control systems. A 5-sided approximate sensor, two photoelectric sensors (BR56-DDT-P and BEN9M-TFR), four CMOS, four BCD-7-segment driven by CD4511B, two relays (2-pole and 3-pole), six voltages, ammeter measurement, DC motor, and 24VDC power supply, connect through connectors and pinions. Results of all the experiments show the trainer satisfying requirements of undergraduate and postgraduate projects involving conventional electronic and classical control systems.展开更多
A sinusoidal voltage wave generator is proposed based on the use of micro-processor digital signals with programmable duty-cycles, with application to real-time Electrical Cell-substrate Impedance Spectroscopy (ECIS) ...A sinusoidal voltage wave generator is proposed based on the use of micro-processor digital signals with programmable duty-cycles, with application to real-time Electrical Cell-substrate Impedance Spectroscopy (ECIS) assays in cell cultures. The working principle relies on the time convolution of the programmed microcontroller (μC) digital signals. The expected frequency is easily tuned on the bio-impedance spectroscopy range [100 Hz, 1 MHz] thanks to the μC clock frequency selection. This system has been simulated and tested on the 8 bits μC Arduino<sup>TM </sup>Uno with ATmega328 version. Results obtained prove that only three digital signals are required to fit the general specification in ECIS experiments, below 1% THD accuracy, and show the appropriateness of the system for the real-time monitoring of this type of biological experiments.展开更多
This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20, which is a 16-bit high performance member of the MCS96 microcontroller family. The electrical...This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20, which is a 16-bit high performance member of the MCS96 microcontroller family. The electrical and functional tests were made in three irradiation environments: neutron, gamma rays, combined irradiation of neutron and gamma rays. The experimental results show that the neutron irradiation can affect the total ionizing dose behaviour. Compared with the single radiation environment, the microcontroller exhibits considerably more severe degradation in neutron and gamma ray synergistic irradiation. This phenomenon may cause a significant hardness assurance problem.展开更多
The build-in structure of microcontroller EM78P458 and its application in supervising the water level of solar water heater are introduced. The circuit and the flow chart of AD conversion program are depicted. In the ...The build-in structure of microcontroller EM78P458 and its application in supervising the water level of solar water heater are introduced. The circuit and the flow chart of AD conversion program are depicted. In the end, the design of assembly language program about the AD conversion is introduced.展开更多
This research assesses the speed of saline fluid in vein vessels using venipuncture medical kit as well as DC submersive pumps that are being controlled by a microcontroller. The microcontroller is monitored and gover...This research assesses the speed of saline fluid in vein vessels using venipuncture medical kit as well as DC submersive pumps that are being controlled by a microcontroller. The microcontroller is monitored and governed using a software IDE interface installed on a powerful laptop. Saline solution is being pumped through a medical syringe at variable speeds up to a maximum of 18.39 cm/second to the vein. The novel technique in this research is the usage of two pumps called Pump 1 and Pump 2. Pump 1 is used to physically model the flow of “blood” in human vein and the second pump (Pump 2) is used to generate the accelerated saline particles that are used to break the yellow grease that is placed on the inside of the vein’s wall. A tiny brush is briefly dipped into yellow grease, and then it is used to place one layer (one turn) of yellow grease on the inside of the vein’s wall, and then this procedure is repeated to place consecutive layers of yellow grease onto the inside of the wall of the vein vessel using a tiny brush. It was found that accelerated saline particles can in fact destroy fats that are built up inside the veins’ walls.展开更多
The combination of sensor and computer technology makes the measurement of various physical quantities easy,convenient and smart.In this article,a digital pressure gauge that is suitable for measuring liquid pressure ...The combination of sensor and computer technology makes the measurement of various physical quantities easy,convenient and smart.In this article,a digital pressure gauge that is suitable for measuring liquid pressure is designed.The design of high precision digital pressure gauge uses pressure sensor as its foundation and uses {ATmega16} as its controller.展开更多
Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving ...Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving the power factor, the customer can reduce its power demand and potentially increase efficiency of their equipment. A PIC microcontroller is used to switch capacitor banks to compensate for the reactive power. In order to determine the size of the capacitor bank needed, the microcontroller calculates the phase difference between the voltage and the current. The results obtained based on the lagging power factor for three test loads show an improvement in the power factor from 0.52 to 0.96 under different test load conditions.展开更多
A meteorological data acquisition system is built using a PIC16F877A microcontroller and electric output-based sensors. This system is programmed in C language using the PCWH compiler. It is smart, accurate, cheap, sm...A meteorological data acquisition system is built using a PIC16F877A microcontroller and electric output-based sensors. This system is programmed in C language using the PCWH compiler. It is smart, accurate, cheap, small, light and easily movable. It is designed to automatically get instantaneous measurements of air temperature, atmospheric pressure, and relative humidity. Depending on their utilisation, these measurements are collected with repetition rate tuneable from one minute to one hour. They are displayed on LCD screen and transferred to a personal computer where they are stored and processed. As an application, such data are recorded in situ and used to estimate the radio refractivity of air near the ground in real time. This parameter is necessary to account for the propagation of radiofrequency waves through the lower atmosphere, during wireless transmissions.展开更多
This work reports the development of a microcontroller based control system to change the speed?of?a DC motor. Pulse Width Modulation?(PWM)?technique was used to control the amount of power delivered to the load (the ...This work reports the development of a microcontroller based control system to change the speed?of?a DC motor. Pulse Width Modulation?(PWM)?technique was used to control the amount of power delivered to the load (the DC motor) without dissipating any wasted power. The components and assembly of this microcontroller circuit are highlighted in this paper, and the constructed circuit tested. This device was used to control the speed of a rotating fan attached to a DC motor. The DC motor speed variations were read from a Tachometer connected to this motor and the results obtained show good agreement with our expectations. DC Motor speed microcontroller devices find applications in many areas of life, and its applications in small scale industrial settings will no doubt enhance the quest for development in a developing nation like ours.展开更多
A low component count, microcontroller-based potentiostat circuit was developed through the use of operational amplifiers arranged in different feedback configurations. This was developed to alleviate the cost burden ...A low component count, microcontroller-based potentiostat circuit was developed through the use of operational amplifiers arranged in different feedback configurations. This was developed to alleviate the cost burden of equipment procurement in low-cost and budget applications. Simplicity was achieved in the design by the use of the microcontroller’s native functionalities and a low-cost R/2R resistor ladder digital-to-analogue converter. The potentiostat was used to investigate the Ni2+/Ni(s) redox couple in a 3-electrode cell with a silver/silver chloride reference electrode and graphite counter and working electrodes. Linear sweep voltammograms were ob-tained at scan rates of 10, 20, 30 and 40 mV/s. The analysis of the peak current versus (scan rate)1/2 plot indicated that the Ni2+/Ni(s) reduction, though conforming to the Randles-Sevcik equation, was a non-reversible redox reaction.展开更多
LED-based moving-message displays are becoming appreciated among the general public for transmitting information to groups of people quickly. This work presents a simple design and implementation of a microcontroller-...LED-based moving-message displays are becoming appreciated among the general public for transmitting information to groups of people quickly. This work presents a simple design and implementation of a microcontroller-based electronic moving message display system. The design involves the arrangement of Light Emitting Diodes (LEDs) and the programming of a microcontroller that controls and determines the pattern and session of the display. The implementation of a moving message displays a text containing 22 characters (i.e. WELCOME TO DEPT. OF PHYSICS). The electronic message display helps to pass information, educates, enlightens, facilitates commercial activities through the advertisement and marketing of goods and services, description of places, etc. The ease in which it displays information makes it a veritable, suitable, and excellent tool for passing information fast and pleasurable to the public. Furthermore, it enhances the response to information in an attractive way and manner in which it displays messages. The microcontroller used in this work is the PIC16F84A. It belongs to a class of 8-bit microcontrollers of RISC (reduced instructions set) architecture. Its output controls the switching of the relays through a transistor switching stage that switches its socket. The LED matrix (array) is arranged in parallel and soldered to a Vero board with the microcontroller and other electronic components, such as resistors, capacitors, transistors, relays, LEDs, diodes, and transformers. In view, this work served as a means of digging into the technology involved in the use of a microcontroller and some other basic electronic components and enhanced visualization of message display.展开更多
In this paper new technique is developed to monitor the health status of the PV panels in the array. For finding the health status short circuit current is measured continuously over a fixed time period. This techniqu...In this paper new technique is developed to monitor the health status of the PV panels in the array. For finding the health status short circuit current is measured continuously over a fixed time period. This technique can classify the health status into four categories such as Healthy, Low Fault, Medium Fault and High Fault. By this classification faulty operation can be rectified and power generation may be improved. In case of high faults, PV panels can be protected. The cost requirement for the implementation is very low. The proposed technique is implemented in MATLAB Simulation and hardware. The array considered in this paper is 2 × 2 Series Parallel.展开更多
文摘The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio.
文摘To ensure the safety of residents’lives and property by using automatic opening and closing of ordinary windows,this article designs an intelligent window automatic monitoring system.The article proposes a software and hardware design scheme for the system,which comprises a microcontroller control module,temperature and humidity detection module,harmful gas detection module,rainfall detection module,human thermal radiation induction module,Organic Light-Emitting Diode(OLED)display module,stepper motor drive module,Wi-Fi communication module,etc.Users use this system to monitor environmental data such as temperature,humidity,rainfall,harmful gas concentrations,and human health.Users can control the opening and closing of windows through manual,microcontroller,and mobile application(app)remote methods,providing users with a more convenient,comfortable,and safe living environment.
文摘Redundancy control can effectively enhance the stability and robustness of a system.Based on the conventional redundancy control switchover and majority arbitration strategy,this paper introduces the concept of heterogeneity and dynamics,constructs a dynamic heterogeneous redundancy-based microcontroller architecture DHR-MCU,and designs a fixed-leader distributed consensus algorithm that satisfies the program running state control of this architecture.The theoretical analysis and actual measurement of the prototype system prove that this architecture has good anti-attack and self-recovery capabilities under normal functions and performances and meets the general robust features in terms of safety and security.
文摘Security is a serious concern, whether it may be the security of assets, data and human life. Providing humans with security and safety for their belongings and items is an important need. A smart lock door project/ with different types of methods for entry, like fingerprint and authentication PIN code is suggested with an unnoticeable face tracking camera capturing a photo in case of error data entry. It is to be controlled via the user’s smartphone using Blynk with the implementation of IoT. This technology is made with two microcontrollers. ESP32 is used to control the solenoid lock, fingerprint sensor and keypad. ESP32-CAM is used to capture a photo and send it to the owner’s smartphone to be viewed on Telegram application. Many conclusions are extracted from system results, as well as suggested ideas for future work.
基金Research on Electromagnetic Scatter Character of very Complicate Object(69571021)
文摘By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the programe of writing operation is given.
文摘Demands for low-energy microcontrollers have been increasing in recent years. Since most microcontrollers achieve user programmability by integrating nonvolatile (NV) memories such as flash memories for storing their programs, the large power consumption required in accessing an NV memory has become a major problem. This problem becomes critical when the power supply voltage of NV microcontrollers is decreased. We can solve this problem by introducing an instruction cache, thus reducing the access frequency of the NV memory. Unlike general-purpose microprocessors, microcontrollers used for real-time applications in embedded systems must accurately calculate program execution time prior to its execution. Therefore, we introduce a “transparent” instruction cache, which does not change the existing NV microcontroller’s cycle-level execution time, for reducing power and energy consumption, but not for improving the processing speed. We have conducted detailed microar chitecture design based on the architecture of a major industrial microcontroller, and we evaluated power and energy consumption for several benchmark programs. Our evaluation shows that the proposed instruction cache can successfully reduce energy consumption in a fairly wide range of practical NV microcontroller configurations.
文摘This paper describes the implementation of a PIC microcontroller in a conventional laboratory-type electronic trainer. The work comprises software for the PIC and hardware for the software. The PIC controller uses an EasyPIC6 board and includes a PC-interfaced programmer for the PIC chip. It has many external modules: 128 × 64 graphic LCD display, 2 × 16 LCD display, 4 × 4 keypad, and port expander, all in the same bench. The trainer is capable of 36 experiments in logic/analogue electronic and control systems. A 5-sided approximate sensor, two photoelectric sensors (BR56-DDT-P and BEN9M-TFR), four CMOS, four BCD-7-segment driven by CD4511B, two relays (2-pole and 3-pole), six voltages, ammeter measurement, DC motor, and 24VDC power supply, connect through connectors and pinions. Results of all the experiments show the trainer satisfying requirements of undergraduate and postgraduate projects involving conventional electronic and classical control systems.
文摘A sinusoidal voltage wave generator is proposed based on the use of micro-processor digital signals with programmable duty-cycles, with application to real-time Electrical Cell-substrate Impedance Spectroscopy (ECIS) assays in cell cultures. The working principle relies on the time convolution of the programmed microcontroller (μC) digital signals. The expected frequency is easily tuned on the bio-impedance spectroscopy range [100 Hz, 1 MHz] thanks to the μC clock frequency selection. This system has been simulated and tested on the 8 bits μC Arduino<sup>TM </sup>Uno with ATmega328 version. Results obtained prove that only three digital signals are required to fit the general specification in ECIS experiments, below 1% THD accuracy, and show the appropriateness of the system for the real-time monitoring of this type of biological experiments.
文摘This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20, which is a 16-bit high performance member of the MCS96 microcontroller family. The electrical and functional tests were made in three irradiation environments: neutron, gamma rays, combined irradiation of neutron and gamma rays. The experimental results show that the neutron irradiation can affect the total ionizing dose behaviour. Compared with the single radiation environment, the microcontroller exhibits considerably more severe degradation in neutron and gamma ray synergistic irradiation. This phenomenon may cause a significant hardness assurance problem.
基金Research on electromaganetic scatter character of very complicate object!(695 71021)
文摘The build-in structure of microcontroller EM78P458 and its application in supervising the water level of solar water heater are introduced. The circuit and the flow chart of AD conversion program are depicted. In the end, the design of assembly language program about the AD conversion is introduced.
文摘This research assesses the speed of saline fluid in vein vessels using venipuncture medical kit as well as DC submersive pumps that are being controlled by a microcontroller. The microcontroller is monitored and governed using a software IDE interface installed on a powerful laptop. Saline solution is being pumped through a medical syringe at variable speeds up to a maximum of 18.39 cm/second to the vein. The novel technique in this research is the usage of two pumps called Pump 1 and Pump 2. Pump 1 is used to physically model the flow of “blood” in human vein and the second pump (Pump 2) is used to generate the accelerated saline particles that are used to break the yellow grease that is placed on the inside of the vein’s wall. A tiny brush is briefly dipped into yellow grease, and then it is used to place one layer (one turn) of yellow grease on the inside of the vein’s wall, and then this procedure is repeated to place consecutive layers of yellow grease onto the inside of the wall of the vein vessel using a tiny brush. It was found that accelerated saline particles can in fact destroy fats that are built up inside the veins’ walls.
基金National Natural Science Foundation of China(No.60804034)Natural Science Foundation of Shandong Province(No.ZR2009GQ006)+5 种基金Project of Science and Technology of Qingdao Economic and Technological Development Area(2009-2-39)China Postdoctoral Science Foundation(No.20100471521)Special Financial Grant from China Postdoctoral Science Foundation(No.201104632)Innovation Project Special Fund for Post Doctors of Shandong Province(No.201002028)Shandong University of Science and Technology Research Fund(No.2010KYJQ105)Project of Shandong Province Higher Educational Science and Technology Program(No.J11LG53)
文摘The combination of sensor and computer technology makes the measurement of various physical quantities easy,convenient and smart.In this article,a digital pressure gauge that is suitable for measuring liquid pressure is designed.The design of high precision digital pressure gauge uses pressure sensor as its foundation and uses {ATmega16} as its controller.
文摘Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving the power factor, the customer can reduce its power demand and potentially increase efficiency of their equipment. A PIC microcontroller is used to switch capacitor banks to compensate for the reactive power. In order to determine the size of the capacitor bank needed, the microcontroller calculates the phase difference between the voltage and the current. The results obtained based on the lagging power factor for three test loads show an improvement in the power factor from 0.52 to 0.96 under different test load conditions.
文摘A meteorological data acquisition system is built using a PIC16F877A microcontroller and electric output-based sensors. This system is programmed in C language using the PCWH compiler. It is smart, accurate, cheap, small, light and easily movable. It is designed to automatically get instantaneous measurements of air temperature, atmospheric pressure, and relative humidity. Depending on their utilisation, these measurements are collected with repetition rate tuneable from one minute to one hour. They are displayed on LCD screen and transferred to a personal computer where they are stored and processed. As an application, such data are recorded in situ and used to estimate the radio refractivity of air near the ground in real time. This parameter is necessary to account for the propagation of radiofrequency waves through the lower atmosphere, during wireless transmissions.
文摘This work reports the development of a microcontroller based control system to change the speed?of?a DC motor. Pulse Width Modulation?(PWM)?technique was used to control the amount of power delivered to the load (the DC motor) without dissipating any wasted power. The components and assembly of this microcontroller circuit are highlighted in this paper, and the constructed circuit tested. This device was used to control the speed of a rotating fan attached to a DC motor. The DC motor speed variations were read from a Tachometer connected to this motor and the results obtained show good agreement with our expectations. DC Motor speed microcontroller devices find applications in many areas of life, and its applications in small scale industrial settings will no doubt enhance the quest for development in a developing nation like ours.
文摘A low component count, microcontroller-based potentiostat circuit was developed through the use of operational amplifiers arranged in different feedback configurations. This was developed to alleviate the cost burden of equipment procurement in low-cost and budget applications. Simplicity was achieved in the design by the use of the microcontroller’s native functionalities and a low-cost R/2R resistor ladder digital-to-analogue converter. The potentiostat was used to investigate the Ni2+/Ni(s) redox couple in a 3-electrode cell with a silver/silver chloride reference electrode and graphite counter and working electrodes. Linear sweep voltammograms were ob-tained at scan rates of 10, 20, 30 and 40 mV/s. The analysis of the peak current versus (scan rate)1/2 plot indicated that the Ni2+/Ni(s) reduction, though conforming to the Randles-Sevcik equation, was a non-reversible redox reaction.
文摘LED-based moving-message displays are becoming appreciated among the general public for transmitting information to groups of people quickly. This work presents a simple design and implementation of a microcontroller-based electronic moving message display system. The design involves the arrangement of Light Emitting Diodes (LEDs) and the programming of a microcontroller that controls and determines the pattern and session of the display. The implementation of a moving message displays a text containing 22 characters (i.e. WELCOME TO DEPT. OF PHYSICS). The electronic message display helps to pass information, educates, enlightens, facilitates commercial activities through the advertisement and marketing of goods and services, description of places, etc. The ease in which it displays information makes it a veritable, suitable, and excellent tool for passing information fast and pleasurable to the public. Furthermore, it enhances the response to information in an attractive way and manner in which it displays messages. The microcontroller used in this work is the PIC16F84A. It belongs to a class of 8-bit microcontrollers of RISC (reduced instructions set) architecture. Its output controls the switching of the relays through a transistor switching stage that switches its socket. The LED matrix (array) is arranged in parallel and soldered to a Vero board with the microcontroller and other electronic components, such as resistors, capacitors, transistors, relays, LEDs, diodes, and transformers. In view, this work served as a means of digging into the technology involved in the use of a microcontroller and some other basic electronic components and enhanced visualization of message display.
文摘In this paper new technique is developed to monitor the health status of the PV panels in the array. For finding the health status short circuit current is measured continuously over a fixed time period. This technique can classify the health status into four categories such as Healthy, Low Fault, Medium Fault and High Fault. By this classification faulty operation can be rectified and power generation may be improved. In case of high faults, PV panels can be protected. The cost requirement for the implementation is very low. The proposed technique is implemented in MATLAB Simulation and hardware. The array considered in this paper is 2 × 2 Series Parallel.