This paper analyses the transient characteristics of high temperature CMOS inverters and gate circuits, and gives the computational formulas of their rise time, fall time and delay time. It may be concluded that the t...This paper analyses the transient characteristics of high temperature CMOS inverters and gate circuits, and gives the computational formulas of their rise time, fall time and delay time. It may be concluded that the transient characteristics of CMOS inverters and gate circuits deteriorate due to the reduction of carrier mobilities and threshold voltages of MOS transistors and the increase of leakage currents of MOS transistors drain terminal pn junctions. The calculation results can explain the experimental phenomenon.展开更多
The project has as its aim the design and implementation of the control of temperature in the cockpit of the prototype of neonatal life support equipment ESVIN based on the international standard IEC 60601-2-19 concer...The project has as its aim the design and implementation of the control of temperature in the cockpit of the prototype of neonatal life support equipment ESVIN based on the international standard IEC 60601-2-19 concerning the basic security and operation of the neonatal incubators. The prototype has been developed and is important because the cockpit is a new concept of medical equipment of neonatal life support. There was a modeling of the system of heating of the incubator using the concepts of system identification with the purpose of finding a mathematical model that describes the dynamic behavior of the system. Then, design and implement the strategy of feedback control with digital PID （proportional-integral-derivative） algorithm. The model allowed the design and implementation of a digital PID controller that meets in a satisfactory manner with the requirements, in accordance with the international standard. The control system implemented in the neonatal incubator ESVIN improved the effectiveness of the neonatal life support equipment in regard to temperature controller of the cockpit.展开更多
The tensile response, the low cycle fatigue （LCF） resistance, and the creep behavior of an aluminum （A1） cast alloy are studied at ambient and elevated temperatures. A non-contact real-time optical extensometer ba...The tensile response, the low cycle fatigue （LCF） resistance, and the creep behavior of an aluminum （A1） cast alloy are studied at ambient and elevated temperatures. A non-contact real-time optical extensometer based on the digital image correlation （DIC） is developed to achieve strain measurements without damage to the specimen. The optical extensometer is validated and used to monitor dynamic strains during the mechanical experiments. Results show that Young＇s modulus of the cast alloy decreases with the increasing temperature, and the percentage elongation to fracture at 100 ℃ is the lowest over the temperature range evaluated from 25 ℃ to 300 ℃. In the LCF test, the fatigue strength coefficient decreases, whereas the fatigue strength exponent increases with the rising temperature. The fatigue ductility at 100 ℃. As expected, the resistance to and changes from 200 ℃ to 300 ℃. coefficient and exponent reach maximum values creep decreases with the increasing temperature展开更多
InGaSb/AlGaAsSb double-quantum-well diode lasers emitting around 2 μm are demonstrated. The AlGaAsSb barriers of the lasers are grown with digital alloy techniques consisting of binary AlSb/AlAs/GaSb short-period pai...InGaSb/AlGaAsSb double-quantum-well diode lasers emitting around 2 μm are demonstrated. The AlGaAsSb barriers of the lasers are grown with digital alloy techniques consisting of binary AlSb/AlAs/GaSb short-period pairs. Peak power conversion efficiency of 26% and an efficiency higher than 16% at 1 W are achieved at continuous-wave operation for a 2-mm-long and 100-μm-wide stripe laser. The maximum output power of a single emitter reaches to 1.4 W at 7 A.19-emitter bars with maximum efficiency higher than 20% and maximum power of 16 W are fabricated. Lasers with the short-period-pair barriers are proved to have improved temperature properties and wavelength stabilities. The characteristic temperature(T_0) is up to 140?C near room temperature(25–55?C).展开更多
The hot-section parts easily occur the creep-fatigued interaction under the condition of mechanicalthermal coupled load during the period of service, which may lead to the damage of the parts, and therefore, the measu...The hot-section parts easily occur the creep-fatigued interaction under the condition of mechanicalthermal coupled load during the period of service, which may lead to the damage of the parts, and therefore, the measurement and characterization of thermal-deformed fields of the parts are important to understand its damage process. Aiming at relevant demand, the bilateral telecentric-multispectral imaging system was established, the research of synchronous measurement technique of the temperature and deformation fields was developed. On the one hand, the measurement technology for surface temperature of the object was developed using the two-color images captured by the multispectral camera with bilateral telecentric lens and combined with colorimetric method. On the other hand, the 2 D-DIC measurement technique of the multispectral camera was developed by conducting digital image correlation analysis using the blue light images before and after deformation, which can measure the high temperature deformation field of the object(the blue light images were filtered by multispectral camera).Results showed that the bilateral telecentric lens is used to replace the ordinary optical lens for imaging,which can effectively eliminate the distortion of the multispectral imaging system. Since the temperature measurement process of this measurement system is little affected by the emissivity of the object, therefore, it has excellent robustness. The thermal expansion coefficients of the nickel alloys are evaluated at the temperature ranges of 700–1000℃, indicating this system can achieve the synchronous and precise measurement of the temperature and deformation fields of the object.展开更多
Purpose: In this project, we developed novel methods to quantify changes in tumor hypoxia following a mild tempera-ture hyperthermia (MTH) treatment in rat HT29 human colon adenocarcinoma xenograft. Materials and Meth...Purpose: In this project, we developed novel methods to quantify changes in tumor hypoxia following a mild tempera-ture hyperthermia (MTH) treatment in rat HT29 human colon adenocarcinoma xenograft. Materials and Methods: An exogenous hypoxia marker (IAZGP) was labeled with two radioisotopes of iodine (131I and 123I, respectively) to form two distinct tracers. The two tracers were injected into HT29-bearing nude rats 4-hour before and immediately following 41.5℃, 45-minute mild hyperthermia treatment. The distributions of the two hypoxia tracers were obtained by performing digital autoradiography on tumor sections, and image processing resulted in quantitative information at 50 μm pixel size. Results: Following the hyperthermia treatment, there was a remarkable decrease in hypoxia tracer binding. The average whole tumor hypoxia tracer targeted fraction in five animals changed from 30.3% ± 9.7% to 13.0% ± 5.3% after the hyperthermia treatment (P = 0.001). Detailed pixelby-pixel analysis of the image data revealed a decline in hypoxia tracer uptake after hyperthermia in most regions. However, there was concomitant emergence of some new regions of hypoxia identified by increased tracer uptake. In the control group, the overall hypoxia tracer targeted fraction remained almost constant, with some hypoxic tracer redistribution (putative acute hypoxia) observed. Conclusion: Reoxygenation occurred in the rat HT29 xenograft following MTH treatment. This was evident with preponderance of decreased hypoxia specific tracer uptake on tumor sections. Our methodology might be a useful tool in hypoxia study.展开更多
Abstract: A new setup of measuring temperature is developed, which the probe is a micro- power consumptive one with CMOS circuit and is driven by optical power. For transmitting the measured signal and optical power s...Abstract: A new setup of measuring temperature is developed, which the probe is a micro- power consumptive one with CMOS circuit and is driven by optical power. For transmitting the measured signal and optical power signal in a long distance, the fiber technology is applied in this setup.展开更多
This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determinin...This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determining the dynamic limit in a PQ diagram. The paper also addresses procedures of improving the accuracy of surface temperature measurement using the contact DS 18B20 digital temperature probes. The paper also provides experimental results of direct temperature measurement of the excitation winding surface conducted in the salient pole synchronous generator in the rotation.展开更多
Accurate and reliable information about the temperature of the synchronous generators excitation winding hot spot is necessary to determine the dynamic limit caused by excitation winding overheating in the PQ diagram....Accurate and reliable information about the temperature of the synchronous generators excitation winding hot spot is necessary to determine the dynamic limit caused by excitation winding overheating in the PQ diagram. For good estimation of a position and the hot spot temperature it is decided to mount 19 temperature probes on one pole of the 6-pole, 400 kVA. 50 llz synchronous generator. Due to a large number of the probes and because the probes should be glued with the metal epoxy it was assumed that mounting of the probes will disrupt the temperature field of the excitation winding. To get the answer to this question the excitation winding resistance was measured betbre and after mounting the probes, in a hot and a cold state. Temperature rise can be estimated if the resistance ratio in the hot and the cold state is known. The paper also addresses the analysis of the measurement accuracy. The result shows that, there is no significant influence on the temperature when mounting the 19 temperature probes which covered 10% of the pole excitation winding surface.展开更多
As a novel three dimensional digital image correlation （3D DIC） method, the bi-prism-based single lens （BSL） 3D DIC method has been proposed and developed in recent years. Making use ofa bi-prism, this method is a...As a novel three dimensional digital image correlation （3D DIC） method, the bi-prism-based single lens （BSL） 3D DIC method has been proposed and developed in recent years. Making use ofa bi-prism, this method is able to perform a 3D DIC measurement using only a single camera. Thus, the integration level of a BSL 3D DIC system could be much higher than that of the double-camera 3D DIC system. In this paper, using a small-angle bi-prism and a camera with a longer focal length, a special BSL 3D DIC system with a long working distance is designed for measurements in extreme environments. The principle of the system is first studied, and practical methods are then proposed for the system set-up and the determination of system parameters. Then, feasibility of the measurement system is verified by out-of-plane rigid-body translation tests. Finally, the BSL 3D DIC system is proven to be capable of combining with a high-temperature testing instrument to perform deformation tests in a high-temperature environment of up to 1500℃.展开更多
基金Supported by the National Native Science Foundation of China
文摘This paper analyses the transient characteristics of high temperature CMOS inverters and gate circuits, and gives the computational formulas of their rise time, fall time and delay time. It may be concluded that the transient characteristics of CMOS inverters and gate circuits deteriorate due to the reduction of carrier mobilities and threshold voltages of MOS transistors and the increase of leakage currents of MOS transistors drain terminal pn junctions. The calculation results can explain the experimental phenomenon.
文摘The project has as its aim the design and implementation of the control of temperature in the cockpit of the prototype of neonatal life support equipment ESVIN based on the international standard IEC 60601-2-19 concerning the basic security and operation of the neonatal incubators. The prototype has been developed and is important because the cockpit is a new concept of medical equipment of neonatal life support. There was a modeling of the system of heating of the incubator using the concepts of system identification with the purpose of finding a mathematical model that describes the dynamic behavior of the system. Then, design and implement the strategy of feedback control with digital PID （proportional-integral-derivative） algorithm. The model allowed the design and implementation of a digital PID controller that meets in a satisfactory manner with the requirements, in accordance with the international standard. The control system implemented in the neonatal incubator ESVIN improved the effectiveness of the neonatal life support equipment in regard to temperature controller of the cockpit.
基金supported by the National Natural Science Foundation of China(Nos.11372173,11672347,and 11727804)the Science and Technology Development Foundation of Shanghai Automobile Industry(No.1514)
文摘The tensile response, the low cycle fatigue （LCF） resistance, and the creep behavior of an aluminum （A1） cast alloy are studied at ambient and elevated temperatures. A non-contact real-time optical extensometer based on the digital image correlation （DIC） is developed to achieve strain measurements without damage to the specimen. The optical extensometer is validated and used to monitor dynamic strains during the mechanical experiments. Results show that Young＇s modulus of the cast alloy decreases with the increasing temperature, and the percentage elongation to fracture at 100 ℃ is the lowest over the temperature range evaluated from 25 ℃ to 300 ℃. In the LCF test, the fatigue strength coefficient decreases, whereas the fatigue strength exponent increases with the rising temperature. The fatigue ductility at 100 ℃. As expected, the resistance to and changes from 200 ℃ to 300 ℃. coefficient and exponent reach maximum values creep decreases with the increasing temperature
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61790580 and 61435012)the National Basic Research Program of China(Grant No.2014CB643903)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YJKYYQ20170032)
文摘InGaSb/AlGaAsSb double-quantum-well diode lasers emitting around 2 μm are demonstrated. The AlGaAsSb barriers of the lasers are grown with digital alloy techniques consisting of binary AlSb/AlAs/GaSb short-period pairs. Peak power conversion efficiency of 26% and an efficiency higher than 16% at 1 W are achieved at continuous-wave operation for a 2-mm-long and 100-μm-wide stripe laser. The maximum output power of a single emitter reaches to 1.4 W at 7 A.19-emitter bars with maximum efficiency higher than 20% and maximum power of 16 W are fabricated. Lasers with the short-period-pair barriers are proved to have improved temperature properties and wavelength stabilities. The characteristic temperature(T_0) is up to 140?C near room temperature(25–55?C).
基金the National Natural Science Foundation of China(Grant Nos.12032013 and 11972209)the National Key Research and Development Program of China(Grant No.2017YFB1103900)the National Science and Technology Major Project(Grant No.2017-VⅠ-0003-0073).
文摘The hot-section parts easily occur the creep-fatigued interaction under the condition of mechanicalthermal coupled load during the period of service, which may lead to the damage of the parts, and therefore, the measurement and characterization of thermal-deformed fields of the parts are important to understand its damage process. Aiming at relevant demand, the bilateral telecentric-multispectral imaging system was established, the research of synchronous measurement technique of the temperature and deformation fields was developed. On the one hand, the measurement technology for surface temperature of the object was developed using the two-color images captured by the multispectral camera with bilateral telecentric lens and combined with colorimetric method. On the other hand, the 2 D-DIC measurement technique of the multispectral camera was developed by conducting digital image correlation analysis using the blue light images before and after deformation, which can measure the high temperature deformation field of the object(the blue light images were filtered by multispectral camera).Results showed that the bilateral telecentric lens is used to replace the ordinary optical lens for imaging,which can effectively eliminate the distortion of the multispectral imaging system. Since the temperature measurement process of this measurement system is little affected by the emissivity of the object, therefore, it has excellent robustness. The thermal expansion coefficients of the nickel alloys are evaluated at the temperature ranges of 700–1000℃, indicating this system can achieve the synchronous and precise measurement of the temperature and deformation fields of the object.
文摘Purpose: In this project, we developed novel methods to quantify changes in tumor hypoxia following a mild tempera-ture hyperthermia (MTH) treatment in rat HT29 human colon adenocarcinoma xenograft. Materials and Methods: An exogenous hypoxia marker (IAZGP) was labeled with two radioisotopes of iodine (131I and 123I, respectively) to form two distinct tracers. The two tracers were injected into HT29-bearing nude rats 4-hour before and immediately following 41.5℃, 45-minute mild hyperthermia treatment. The distributions of the two hypoxia tracers were obtained by performing digital autoradiography on tumor sections, and image processing resulted in quantitative information at 50 μm pixel size. Results: Following the hyperthermia treatment, there was a remarkable decrease in hypoxia tracer binding. The average whole tumor hypoxia tracer targeted fraction in five animals changed from 30.3% ± 9.7% to 13.0% ± 5.3% after the hyperthermia treatment (P = 0.001). Detailed pixelby-pixel analysis of the image data revealed a decline in hypoxia tracer uptake after hyperthermia in most regions. However, there was concomitant emergence of some new regions of hypoxia identified by increased tracer uptake. In the control group, the overall hypoxia tracer targeted fraction remained almost constant, with some hypoxic tracer redistribution (putative acute hypoxia) observed. Conclusion: Reoxygenation occurred in the rat HT29 xenograft following MTH treatment. This was evident with preponderance of decreased hypoxia specific tracer uptake on tumor sections. Our methodology might be a useful tool in hypoxia study.
文摘Abstract: A new setup of measuring temperature is developed, which the probe is a micro- power consumptive one with CMOS circuit and is driven by optical power. For transmitting the measured signal and optical power signal in a long distance, the fiber technology is applied in this setup.
文摘This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determining the dynamic limit in a PQ diagram. The paper also addresses procedures of improving the accuracy of surface temperature measurement using the contact DS 18B20 digital temperature probes. The paper also provides experimental results of direct temperature measurement of the excitation winding surface conducted in the salient pole synchronous generator in the rotation.
文摘Accurate and reliable information about the temperature of the synchronous generators excitation winding hot spot is necessary to determine the dynamic limit caused by excitation winding overheating in the PQ diagram. For good estimation of a position and the hot spot temperature it is decided to mount 19 temperature probes on one pole of the 6-pole, 400 kVA. 50 llz synchronous generator. Due to a large number of the probes and because the probes should be glued with the metal epoxy it was assumed that mounting of the probes will disrupt the temperature field of the excitation winding. To get the answer to this question the excitation winding resistance was measured betbre and after mounting the probes, in a hot and a cold state. Temperature rise can be estimated if the resistance ratio in the hot and the cold state is known. The paper also addresses the analysis of the measurement accuracy. The result shows that, there is no significant influence on the temperature when mounting the 19 temperature probes which covered 10% of the pole excitation winding surface.
基金supported by the National Natural Science Foundation of China(Grant Nos.11672153,11232008&11227801)
文摘As a novel three dimensional digital image correlation （3D DIC） method, the bi-prism-based single lens （BSL） 3D DIC method has been proposed and developed in recent years. Making use ofa bi-prism, this method is able to perform a 3D DIC measurement using only a single camera. Thus, the integration level of a BSL 3D DIC system could be much higher than that of the double-camera 3D DIC system. In this paper, using a small-angle bi-prism and a camera with a longer focal length, a special BSL 3D DIC system with a long working distance is designed for measurements in extreme environments. The principle of the system is first studied, and practical methods are then proposed for the system set-up and the determination of system parameters. Then, feasibility of the measurement system is verified by out-of-plane rigid-body translation tests. Finally, the BSL 3D DIC system is proven to be capable of combining with a high-temperature testing instrument to perform deformation tests in a high-temperature environment of up to 1500℃.
