介绍了基于EPA（Ethernet for Plant Automation）现场总线的过程控制实验系统的体系结构及系统组成。以温度对象系统为例,介绍了基于EPA的串级系统的实现及实际运行情况。该系统的建成有助于学生了解工控行业的先进技术———现场总线...介绍了基于EPA（Ethernet for Plant Automation）现场总线的过程控制实验系统的体系结构及系统组成。以温度对象系统为例,介绍了基于EPA的串级系统的实现及实际运行情况。该系统的建成有助于学生了解工控行业的先进技术———现场总线控制,掌握具体的工程知识,同时也为科研提供了一个新的平台。展开更多
Color information plays a key role in the research fields of object recognition and image retrieval. However, the actual color varies by the conditions of illumination, especially the open natural daylight. Four diffe...Color information plays a key role in the research fields of object recognition and image retrieval. However, the actual color varies by the conditions of illumination, especially the open natural daylight. Four different color constancy schemes are proposed in the paper to minimize the effects of open illumination conditions. (1) The color constancy scheme based on the image statistics is proposed, which includes the color cast detection and removal. (2) The color constancy scheme based on the color temperature curve is proposed, which combines Gaussian model with linear fitting to estimate color temperature curve. (3) The color constancy scheme based on the double exposure theory is proposed, which is able to reproduce a color image under typical illumination. (4) According to the concepts of supervised learning, the supervised color constancy scheme is proposed. The transformation of color values from unknown illumination to typical illumination is solved by improved Support Vector Regression (SVR).展开更多
Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great intere...Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great interest owing to the high-temperature sensitivity of their photoluminescence,which could be applied to remote optical thermometry(ROT).Herein,all-inorganic and lead-free halide perovskite Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O single crystals(SCs)were prepared through the hydrothermal method and showed a strong temperature dependence of photoluminescence lifetime.Upon Te^(4+) doping,the nonemissive Cs_(2)InCl_(5)·H_(2)O SC exhibits a bright orange emission at 660 nm with a wide full width at half maximum of 180 nm.The strong phonon-exciton coupling promotes the formation of self-trapped excitons in the soft lattice of the zero-dimensional Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC.The Te^(4+) ions with the 5 s^(2) electronic configuration endow the Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC with a strong temperaturedependent photoluminescence lifetime.This SC reaches a maximum specific sensitivity of 0.062 K^(-1) at 320 K,thereby showing the potential advantages of indium-based metal halide perovskites in ROT applications.展开更多
For thermal conduction cases,one can detect the size of an object explicitly by measuring the temperature distribution around it.If the temperature is the only signature we can obtain,we will give an incorrect judgmen...For thermal conduction cases,one can detect the size of an object explicitly by measuring the temperature distribution around it.If the temperature is the only signature we can obtain,we will give an incorrect judgment on the shape or size of the object by disturbing the distribution of it.According to this principle,in this article,we develop a transformation method and design a dual-functional thermal device,which can create a thermal illusion that the object inside it ＂seems＂ to appear bigger or smaller than its original size.This device can functionally switch among magnifier and miniGer at will The proposed device consists of two layers：the cloak and the complementary material.A thermal cloak can make the internal region thermally ＂invisible＂ while the complementary layer offsets this effect.The combination leads to the illusion of magnification and minification.As a result of finite element simulations,the performances of the illusions are confirmed.展开更多
文摘介绍了基于EPA（Ethernet for Plant Automation）现场总线的过程控制实验系统的体系结构及系统组成。以温度对象系统为例,介绍了基于EPA的串级系统的实现及实际运行情况。该系统的建成有助于学生了解工控行业的先进技术———现场总线控制,掌握具体的工程知识,同时也为科研提供了一个新的平台。
基金Supported by the National Natural Science Foundation of China (No.60431020)the Natural Science Foundation of Beijing (No.3052005)the Ph.D. Foundation of Ministry of Education (No.20040005015)
文摘Color information plays a key role in the research fields of object recognition and image retrieval. However, the actual color varies by the conditions of illumination, especially the open natural daylight. Four different color constancy schemes are proposed in the paper to minimize the effects of open illumination conditions. (1) The color constancy scheme based on the image statistics is proposed, which includes the color cast detection and removal. (2) The color constancy scheme based on the color temperature curve is proposed, which combines Gaussian model with linear fitting to estimate color temperature curve. (3) The color constancy scheme based on the double exposure theory is proposed, which is able to reproduce a color image under typical illumination. (4) According to the concepts of supervised learning, the supervised color constancy scheme is proposed. The transformation of color values from unknown illumination to typical illumination is solved by improved Support Vector Regression (SVR).
基金supported by the National Natural Science Foundation of China(U2001214)the Natural Science Foundation of Guangdong Province(2019B1515120050)the Fundamental Research Funds for the Central Universities。
文摘Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great interest owing to the high-temperature sensitivity of their photoluminescence,which could be applied to remote optical thermometry(ROT).Herein,all-inorganic and lead-free halide perovskite Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O single crystals(SCs)were prepared through the hydrothermal method and showed a strong temperature dependence of photoluminescence lifetime.Upon Te^(4+) doping,the nonemissive Cs_(2)InCl_(5)·H_(2)O SC exhibits a bright orange emission at 660 nm with a wide full width at half maximum of 180 nm.The strong phonon-exciton coupling promotes the formation of self-trapped excitons in the soft lattice of the zero-dimensional Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC.The Te^(4+) ions with the 5 s^(2) electronic configuration endow the Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC with a strong temperaturedependent photoluminescence lifetime.This SC reaches a maximum specific sensitivity of 0.062 K^(-1) at 320 K,thereby showing the potential advantages of indium-based metal halide perovskites in ROT applications.
基金Support by the National Natural Science Foundation of China under Grant No.11222544by the Fok Ying Tung Education Foundation under Grant No.131008+1 种基金by the Program for New Century Excellent Talents in University(NCET-12-0121)by the Chinese National Key Basic Research Special Fund under Grant No.2011CB922004
文摘For thermal conduction cases,one can detect the size of an object explicitly by measuring the temperature distribution around it.If the temperature is the only signature we can obtain,we will give an incorrect judgment on the shape or size of the object by disturbing the distribution of it.According to this principle,in this article,we develop a transformation method and design a dual-functional thermal device,which can create a thermal illusion that the object inside it ＂seems＂ to appear bigger or smaller than its original size.This device can functionally switch among magnifier and miniGer at will The proposed device consists of two layers：the cloak and the complementary material.A thermal cloak can make the internal region thermally ＂invisible＂ while the complementary layer offsets this effect.The combination leads to the illusion of magnification and minification.As a result of finite element simulations,the performances of the illusions are confirmed.
