We read with interest the review paper by Tao et al. on thetopic of early severe acute pancreatifis (EASP, defined as severeacute pancreatitis according to the Altanta criteria, with organdysfunction within 72 h after...We read with interest the review paper by Tao et al. on thetopic of early severe acute pancreatifis (EASP, defined as severeacute pancreatitis according to the Altanta criteria, with organdysfunction within 72 h after the start of symptoms) in a recentissue of the World Journal of Gastroenterology. It addressesan important problem in patients with severe acute pancreatitis,namely early organ dysfunction and its effect on outcomes.展开更多
A simple single-stage AC/DC converter circuit with active clamp is presented. The operation theory and state are analyzed. The experimental results show that the voltage across main switch can be clamped to a certain ...A simple single-stage AC/DC converter circuit with active clamp is presented. The operation theory and state are analyzed. The experimental results show that the voltage across main switch can be clamped to a certain value,and zero voltage switching (ZVS) can be achieved. The voltage stress and switching loss are both decreased. In range of the whole load,power factors can be always more than 97%,and the highest efficiency can reach 88%.展开更多
Support vector regression （SVR） method is a novel type of learning machine algorithms, which is seldom applied to the development of urban atmospheric quality models under multiple socio-economic factors. This study...Support vector regression （SVR） method is a novel type of learning machine algorithms, which is seldom applied to the development of urban atmospheric quality models under multiple socio-economic factors. This study presents four SVR models by selecting linear, radial basis, spline, and polynomial functions as kernels, respectively for the prediction of urban dust fall levels. The inputs of the models are identified as industrial coal consumption, population density, traffic flow coefficient, and shopping density coefficient. The training and testing results show that the SVR model with radial basis kernel performs better than the other three both in the training and testing processes. In addition, a number of scenario analyses reveal that the most suitable parameters （insensitive loss function e, the parameter to reduce the influence of error C, and discrete level or average distribution of parameters σ） are 0.001, 0.5, and 2 000, respectively.展开更多
Sense of science and technology has become the trend of modem design, but the commonly acknowledged sense of science and technology is different from science and technology itself. Starting from machine aesthetics and...Sense of science and technology has become the trend of modem design, but the commonly acknowledged sense of science and technology is different from science and technology itself. Starting from machine aesthetics and high-tech style, combined with the changing process of the sense of science and technology, it analyzes the causes and related social factors, style characteristics and manifestations of the sense of science and technology, as well as the inherent relationship of multi-angle analysis technology and the sense of science and technology. It illustrates the social value and defects of artistic expression of the sense of science and technology and reflects on the connection and difference between science and technology on the one hand and the sense of science and technology on the other hand.展开更多
We demonstrate radiation-pressure-driven mechanical oscillations from high optical quality factor silica microdisk resonators on chip. Mechanical quality factors of 3520 in air and 12540 in vacuum for the fundamental ...We demonstrate radiation-pressure-driven mechanical oscillations from high optical quality factor silica microdisk resonators on chip. Mechanical quality factors of 3520 in air and 12540 in vacuum for the fundamental radial breathing modes are obtained from 73 μm-diarneter silica microdisks with mechanical frequencies of -51 MHz. The measured mechanical oscillation threshold powers for the input light are determined to be 62.5 μW in air and down to 26.6 μW in vacuum.展开更多
文摘We read with interest the review paper by Tao et al. on thetopic of early severe acute pancreatifis (EASP, defined as severeacute pancreatitis according to the Altanta criteria, with organdysfunction within 72 h after the start of symptoms) in a recentissue of the World Journal of Gastroenterology. It addressesan important problem in patients with severe acute pancreatitis,namely early organ dysfunction and its effect on outcomes.
文摘A simple single-stage AC/DC converter circuit with active clamp is presented. The operation theory and state are analyzed. The experimental results show that the voltage across main switch can be clamped to a certain value,and zero voltage switching (ZVS) can be achieved. The voltage stress and switching loss are both decreased. In range of the whole load,power factors can be always more than 97%,and the highest efficiency can reach 88%.
基金Projects(2007JT3018, 2008JT1013, 2009FJ4056) supported by the Key Project in Hunan Science and Technology Program, ChinaProject(20090161120014) supported by the New Teachers Sustentation Fund in Doctoral Program, Ministry of Education, China
文摘Support vector regression （SVR） method is a novel type of learning machine algorithms, which is seldom applied to the development of urban atmospheric quality models under multiple socio-economic factors. This study presents four SVR models by selecting linear, radial basis, spline, and polynomial functions as kernels, respectively for the prediction of urban dust fall levels. The inputs of the models are identified as industrial coal consumption, population density, traffic flow coefficient, and shopping density coefficient. The training and testing results show that the SVR model with radial basis kernel performs better than the other three both in the training and testing processes. In addition, a number of scenario analyses reveal that the most suitable parameters （insensitive loss function e, the parameter to reduce the influence of error C, and discrete level or average distribution of parameters σ） are 0.001, 0.5, and 2 000, respectively.
文摘Sense of science and technology has become the trend of modem design, but the commonly acknowledged sense of science and technology is different from science and technology itself. Starting from machine aesthetics and high-tech style, combined with the changing process of the sense of science and technology, it analyzes the causes and related social factors, style characteristics and manifestations of the sense of science and technology, as well as the inherent relationship of multi-angle analysis technology and the sense of science and technology. It illustrates the social value and defects of artistic expression of the sense of science and technology and reflects on the connection and difference between science and technology on the one hand and the sense of science and technology on the other hand.
基金supported by the National Basic Research Program of China(Grant Nos.2012CB921804 and 2011CBA00205)the National Natural Science Foundation of China(Grant Nos.61435007,11104137 and 11321063)
文摘We demonstrate radiation-pressure-driven mechanical oscillations from high optical quality factor silica microdisk resonators on chip. Mechanical quality factors of 3520 in air and 12540 in vacuum for the fundamental radial breathing modes are obtained from 73 μm-diarneter silica microdisks with mechanical frequencies of -51 MHz. The measured mechanical oscillation threshold powers for the input light are determined to be 62.5 μW in air and down to 26.6 μW in vacuum.
