Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previo... more Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.
Background and purpose: The Chest Pain Center accreditation project was launched in 2011 in China... more Background and purpose: The Chest Pain Center accreditation project was launched in 2011 in China as a nationwide effort to improve clinical management of acute chest pain patients. In this study, we summarize the clinical characteristics and in-hospital outcomes of patients undergoing treatment for acute coronary syndrome (ACS) in Chest Pain Centers in China. Methods: Data were based on the Chinese Cardiovascular Association (CCA) Database-Chest Pain Center of 1,745,118 ACS patients admitted at 2,096 accredited Chest Pain Center between January 1, 2016, and December 31, 2021. Patient characteristics, time delays, treatment, and outcomes were analyzed using descriptive analysis. Results: The final analysis included a total of 1,745,118 patients, 699,476 patients (40.1%) with ST segment elevation myocardial infarction (STEMI), 349,572 (20.0%) with non-ST segment elevation myocardial infarction (NSTEMI), and 696,070 (39.9%) with unstable angina (UA). Electrocardiogram (ECG) was conduc...
Electrical storm (ES) remains a major dilemma for clinicians, often presenting as a medical emerg... more Electrical storm (ES) remains a major dilemma for clinicians, often presenting as a medical emergency associated with significant adverse outcomes. The mechanisms behind triggering ES are complex. Although the increased activation of the sympathetic nervous system was widely accepted as a major mechanism in initiating and maintaining ES, it's thought that the interaction between mechanical and electrical substrates may play an important role in some situations. Here we present a case of ES that was refractory to multiple antiarrhythmic medications but was stopped by interatrial shunting. We aim to highlight the importance of mechano-electric feedback (MEF) as the pathophysiological mechanisms of some types of ES and the utility of interatrial shunting as an alternative therapeutic strategy for patients with ES initially refractory to antiarrhythmic medications when there is evidence to indicate increased left ventricular filling pressure or left atrial pressure.
Aiming at the problem of terrain following path planning with tall and isolated obstacles under c... more Aiming at the problem of terrain following path planning with tall and isolated obstacles under complex terrain, a scheme of alternate terrain following and terrain avoiding (alternate TF/TA) is proposed, considering the constraints of terrain, maximum climbing/glide angle, minimum turning radius. First, a new terrain smoothing algorithm is proposed based on the principle of down sampling. Second, the models of uphill and downhill flight path are established by referring to the dubins curves in longitudinal planning; and the particle swarm optimization algorithm and the B-spline curve are applied on lateral planning when the aircraft cannot overfly the obstacle. Finally, the simulation verification shows that the aircraft can effectively fly around tall and isolated obstacles with smooth path and close to the terrain through the proposed scheme. Compared with the traditional terrain following method based on slope, curvature and safety height limits, the total length and average height of the path are reduced by 0.28% and 10.10% respectively.
Due to the extensive excavation of open-pit coal mines in northwest of China, the rock slopes for... more Due to the extensive excavation of open-pit coal mines in northwest of China, the rock slopes formed by special environments are subjected to freeze-thaw (F-T) action, which has a certain impact on their stabilities. In order to evaluate the mechanical properties and micro damage characteristics of coal under different freeze-thaw cycles, uniaxial compression experiments combining acoustic emission tests were conducted. The results suggest that as the number of freeze-thaw cycles increased, elastic modulus of coal samples decreased, the samples showed ductile damage characteristics and initial compaction stage gradually increased. Compared with unfrozen-thawed coal sample, the compressive strength of the coal samples decreased by 23.27% after 10 F-T cycles, 31.06% after 15 F-T cycles, and 36.01% after 20 F-T cycles. The internal fissures in the coal samples transitioned from tensile fissures to shearing fissures, and the samples gradually showed tensile-shear combined failure. The f...
Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previo... more Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.
In this research, a focus is on the development of simplified models to represent the behavior of... more In this research, a focus is on the development of simplified models to represent the behavior of electric machinery within the time-domain models of power systems. Toward this goal, a generator model is considered in which the states include the machine's active and reactive power. In the case of the induction machine, rotor slip is utilized as a state and the steady-state equivalent circuit of the machine is used to calculate active and reactive power. The power network model is then configured to accept the generator and induction machine active and reactive power as inputs and provide machine terminal voltage amplitude and angle as outputs. The potential offered by these models is that the number of dynamic states is greatly reduced compared to traditional machine models. This can lead to increased simulation speed, which has potential benefits in model-based control. A potential disadvantage is that the relationship between the reactive power and terminal voltage requires t...
The high radon concentration in the underground space of the subway station during construction o... more The high radon concentration in the underground space of the subway station during construction often endangers the health of workers. Subway station project No. 16 in Beijing, while under construction, was selected as the main measuring point, a year's monitoring data was obtained to analyse the change of radon concentration. It was found that the concentration of radon was basically within the range of 5 ~ 500 Bq/m3 and showing a low level in the morning and a high level at noon, and presents the seasonal rule, compared with other seasons, the summer radiation is stronger. Furthermore, among the different measuring points, the radon concentration of the heading roadway is the highest, and the construction level of the station hall is the lowest. According to the comprehensive analysis, the concentration of radon during the construction of the subway station is mainly affected by the ambient temperature and air mobility.
Large capacity cascaded battery energy storage system(BESS) is one of the effective means to solv... more Large capacity cascaded battery energy storage system(BESS) is one of the effective means to solve the problem of grid-connection of renewable energy resource such as large-scale wind farm.In allusion to the control strategy for power conditioning system(PCS) of BESS,the proportional resonant(PR) regulator is used to implement the control with zero-steady-state error for instantaneous power in α-β coordinate system;the balancing control of the state of charge(SOC) among clusters,namely the bridge arms of each phase in cascaded BESS,is implemented by means of injecting zero-sequence votlage and the SOC balance of units within the cluster is realized through adding corresponding AC voltage.Simulation results show that faster dynamic response and smaller steady-state error of PCS adopting the control strategy can be attained in instantaneous power control,meanwhile the balancing control of SOC can be achieved effectively,thus,the correctness and feasibility of the control strategy are ...
Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previo... more Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.
Background and purpose: The Chest Pain Center accreditation project was launched in 2011 in China... more Background and purpose: The Chest Pain Center accreditation project was launched in 2011 in China as a nationwide effort to improve clinical management of acute chest pain patients. In this study, we summarize the clinical characteristics and in-hospital outcomes of patients undergoing treatment for acute coronary syndrome (ACS) in Chest Pain Centers in China. Methods: Data were based on the Chinese Cardiovascular Association (CCA) Database-Chest Pain Center of 1,745,118 ACS patients admitted at 2,096 accredited Chest Pain Center between January 1, 2016, and December 31, 2021. Patient characteristics, time delays, treatment, and outcomes were analyzed using descriptive analysis. Results: The final analysis included a total of 1,745,118 patients, 699,476 patients (40.1%) with ST segment elevation myocardial infarction (STEMI), 349,572 (20.0%) with non-ST segment elevation myocardial infarction (NSTEMI), and 696,070 (39.9%) with unstable angina (UA). Electrocardiogram (ECG) was conduc...
Electrical storm (ES) remains a major dilemma for clinicians, often presenting as a medical emerg... more Electrical storm (ES) remains a major dilemma for clinicians, often presenting as a medical emergency associated with significant adverse outcomes. The mechanisms behind triggering ES are complex. Although the increased activation of the sympathetic nervous system was widely accepted as a major mechanism in initiating and maintaining ES, it's thought that the interaction between mechanical and electrical substrates may play an important role in some situations. Here we present a case of ES that was refractory to multiple antiarrhythmic medications but was stopped by interatrial shunting. We aim to highlight the importance of mechano-electric feedback (MEF) as the pathophysiological mechanisms of some types of ES and the utility of interatrial shunting as an alternative therapeutic strategy for patients with ES initially refractory to antiarrhythmic medications when there is evidence to indicate increased left ventricular filling pressure or left atrial pressure.
Aiming at the problem of terrain following path planning with tall and isolated obstacles under c... more Aiming at the problem of terrain following path planning with tall and isolated obstacles under complex terrain, a scheme of alternate terrain following and terrain avoiding (alternate TF/TA) is proposed, considering the constraints of terrain, maximum climbing/glide angle, minimum turning radius. First, a new terrain smoothing algorithm is proposed based on the principle of down sampling. Second, the models of uphill and downhill flight path are established by referring to the dubins curves in longitudinal planning; and the particle swarm optimization algorithm and the B-spline curve are applied on lateral planning when the aircraft cannot overfly the obstacle. Finally, the simulation verification shows that the aircraft can effectively fly around tall and isolated obstacles with smooth path and close to the terrain through the proposed scheme. Compared with the traditional terrain following method based on slope, curvature and safety height limits, the total length and average height of the path are reduced by 0.28% and 10.10% respectively.
Due to the extensive excavation of open-pit coal mines in northwest of China, the rock slopes for... more Due to the extensive excavation of open-pit coal mines in northwest of China, the rock slopes formed by special environments are subjected to freeze-thaw (F-T) action, which has a certain impact on their stabilities. In order to evaluate the mechanical properties and micro damage characteristics of coal under different freeze-thaw cycles, uniaxial compression experiments combining acoustic emission tests were conducted. The results suggest that as the number of freeze-thaw cycles increased, elastic modulus of coal samples decreased, the samples showed ductile damage characteristics and initial compaction stage gradually increased. Compared with unfrozen-thawed coal sample, the compressive strength of the coal samples decreased by 23.27% after 10 F-T cycles, 31.06% after 15 F-T cycles, and 36.01% after 20 F-T cycles. The internal fissures in the coal samples transitioned from tensile fissures to shearing fissures, and the samples gradually showed tensile-shear combined failure. The f...
Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previo... more Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.
In this research, a focus is on the development of simplified models to represent the behavior of... more In this research, a focus is on the development of simplified models to represent the behavior of electric machinery within the time-domain models of power systems. Toward this goal, a generator model is considered in which the states include the machine's active and reactive power. In the case of the induction machine, rotor slip is utilized as a state and the steady-state equivalent circuit of the machine is used to calculate active and reactive power. The power network model is then configured to accept the generator and induction machine active and reactive power as inputs and provide machine terminal voltage amplitude and angle as outputs. The potential offered by these models is that the number of dynamic states is greatly reduced compared to traditional machine models. This can lead to increased simulation speed, which has potential benefits in model-based control. A potential disadvantage is that the relationship between the reactive power and terminal voltage requires t...
The high radon concentration in the underground space of the subway station during construction o... more The high radon concentration in the underground space of the subway station during construction often endangers the health of workers. Subway station project No. 16 in Beijing, while under construction, was selected as the main measuring point, a year's monitoring data was obtained to analyse the change of radon concentration. It was found that the concentration of radon was basically within the range of 5 ~ 500 Bq/m3 and showing a low level in the morning and a high level at noon, and presents the seasonal rule, compared with other seasons, the summer radiation is stronger. Furthermore, among the different measuring points, the radon concentration of the heading roadway is the highest, and the construction level of the station hall is the lowest. According to the comprehensive analysis, the concentration of radon during the construction of the subway station is mainly affected by the ambient temperature and air mobility.
Large capacity cascaded battery energy storage system(BESS) is one of the effective means to solv... more Large capacity cascaded battery energy storage system(BESS) is one of the effective means to solve the problem of grid-connection of renewable energy resource such as large-scale wind farm.In allusion to the control strategy for power conditioning system(PCS) of BESS,the proportional resonant(PR) regulator is used to implement the control with zero-steady-state error for instantaneous power in α-β coordinate system;the balancing control of the state of charge(SOC) among clusters,namely the bridge arms of each phase in cascaded BESS,is implemented by means of injecting zero-sequence votlage and the SOC balance of units within the cluster is realized through adding corresponding AC voltage.Simulation results show that faster dynamic response and smaller steady-state error of PCS adopting the control strategy can be attained in instantaneous power control,meanwhile the balancing control of SOC can be achieved effectively,thus,the correctness and feasibility of the control strategy are ...
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