In recent years,research on nursing interruptions has been conducted at various levels in emergency departments,intensive care units,hemodialysis centers,operating rooms,and sterilization and supply centers.Nursing in...In recent years,research on nursing interruptions has been conducted at various levels in emergency departments,intensive care units,hemodialysis centers,operating rooms,and sterilization and supply centers.Nursing interruptions are closely related to adverse nursing events,and interruptions in operating room nursing can significantly impact the success of a patient’s surgery.However,there is a lack of in-depth theoretical research on safety risk assessment and response decision-making by operating room nurses when faced with nursing interruptions.This article reviews the concept,current status,and impact of nursing interruptions in the operating room,analyzes the cognitive level,coping strategies,and negative emotions of operating room nurses,and elaborates on management strategies to provide references for research and management of nursing interruptions in the operating room.展开更多
Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are...Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are incomplete and spare supraspinal pathways,especially those located within the peripheral white matter of the spinal cord,which includes reticulospinal pathways originating from the medullary reticular formation.Whereas there is abundant literature about the motor cortex,its corticospinal pathway,and its capacity to modulate functional recovery after SCI,less is known about the medullary reticular formation and its reticulospinal pathway.展开更多
AIM： To evaluate the efficacy of interruption of intrauterine infection of HBV with HBIG in pregnant women with positive HBeAg and HBsAg.METHODS： A prospective randomized controlled trial was adopted. Sixty cases wi...AIM： To evaluate the efficacy of interruption of intrauterine infection of HBV with HBIG in pregnant women with positive HBeAg and HBsAg.METHODS： A prospective randomized controlled trial was adopted. Sixty cases with positive HBeAg and HBsAg were coincident with the criteria of inclusion, and 8 cases were excluded. Fifty-two cases were analyzed （28 cases in trial group and 24 in control group）. All cases in trial group received 200 IU HBIG intravenously every 4 wk for 3 times from the 28^th wk. The cases of control group received placebo in the same way. All pregnant women were detected for HBeAg and HBV-DNA at the beginning of the trial and end of the trial （delivery）. The cord blood of all newborns were collected for detecting HBeAg and HBV-DNA simultaneously.RESULTS： For investigation of HBeAg of newborns in trial group, 6 of 28 cases of newborns had positive HBeAg, the HBeAg positive rate being 21.4%, the total rate of 95% CI being 8%-41%. In control group, 19 of 24 cases of newborns had positive HBeAg, HBeAg positive rate was 79.2%, the rate of 95%CI being 5%-93%. By statistical analysis, 2= 17.26, P 〈 0.01, RR = 0.27, 95% CI （6.3 × 10^-6, 8.6 × 10^-5）. For investigation of HBV-DNA of newborns in trial group, 7 of 28 cases of newborns had positive HBV-DNA, HBV-DNA positive rate being 25%, the total rate of 95% CI being 11%-45%. In control group, 20 of 24 cases of newborns had positive HBV-DNA, HBV-DNA positive rate was 83.3%, the total rate of 95% CI being 63%-95%. By statistical analysis, X^2 = 17.62, P 〈 0.01, RR = 0.30, 95% CI （1.5 × 10^-5, 1.7× 10^-4）. The results indicated that there was significant difference in HBeAg positive rate and HBV-DNA positive rate of newborns between the two groups. In trial group, 7 of 28 newborns had HBV-DNA positive, but the HBV-DNA load of newborns was lower than that of their mothers. In control group, 20 of 24 newborns still had HBV-DNA positive, and the HBV-DNA load of newborns was close to those of their mothers. Statistical analysis indicated that there was no significant difference in HBV- DNA load between postnatal women without HBIG intervention and their filial generations （T = 81.5, P 〉 0.1）. CONCLUSION： It is effective and safe to prevent intrauterine infection of HBV with HBIG from the 28^th wk in pregnant women with positive HBeAg and HBsAg. In clinical application, those pregnant women with negative HBeAg and positive HBV-DNA also need to be interrupted by HBIG.展开更多
Objectives:To explore the knowledge,attitude and practice of Chinese nurses regarding nursing interruptions and related factors.Methods:A total of 6,400 nurses from 31 hospitals in China were investigated by using the...Objectives:To explore the knowledge,attitude and practice of Chinese nurses regarding nursing interruptions and related factors.Methods:A total of 6,400 nurses from 31 hospitals in China were investigated by using the Knowledge,Attitude and Practice(KAP)Questionnaire of Nursing Interruptions.The questionnaire consists of three dimensions,knowledge,attitude and practice,containing 10,9 and 7 items,with full score of 50,45 and 28,respectively.Results:The mean overall KAP score regarding nursing interruptions of Chinese nurses was 74.05±16.65(range:26-123),with scores for the knowledge,attitude,and practice component being 21.74±9.80,34.83±6.98,and 17.49±4.97,respectively.Among the nurses,70.8%of them experienced an average level of KAP toward nursing interruptions while 15.5%were at a poor level.The knowledge,attitude,and practice of nursing interruptions were better in chief nurses,managers,nurses with a master degree or above,nurses ever received training,and nurses with a strong agreement to leadership compared to nurses in other groups(P<0.05).In addition,employment type,professional title,position,standardized training and leaders'attention were predictors of KAP in nurses.Conclusion:Chinese nurses have a moderate level of KAP regarding nursing interruptions.Leaders'attention,standardized training,position,professional title and employment type could predict nurses'KAP state of nursing interruptions.Thus,a targeted training program should be implemented for clinical nurses by nursing leaders,with a particular focus on feasibility and professionalism.展开更多
Pituitary stalk interruption syndrome(PSIS)is a rare congenital abnormality characterized by thinning or disappearance of the pituitary stalk,hypoplasia of the anterior pituitary and an ectopic posterior pituitary.Alt...Pituitary stalk interruption syndrome(PSIS)is a rare congenital abnormality characterized by thinning or disappearance of the pituitary stalk,hypoplasia of the anterior pituitary and an ectopic posterior pituitary.Although the etiology of PSIS is still unclear,gene changes and perinatal adverse events such as breech delivery may play important roles in the pathogenesis of PSIS.PSIS can cause multiple hormone deficiencies,such as growth hormone,which then cause a series of changes in the human body.On the one hand,hormone changes affect growth and development,and on the other hand,they could affect human metabolism and subsequently the liver resulting in nonalcoholic fatty liver disease(NAFLD).Under the synergistic effect of multiple mechanisms,the progression of NAFLD caused by PSIS is faster than that due to other causes.Therefore,in addition to early identification of PSIS,timely hormone replacement therapy and monitoring of relevant hormone levels,clinicians should routinely assess the liver function while managing PSIS.展开更多
In this paper, we present a new car-following model by taking into account the effects of the traffic interruption probability on the car-following behaviour of the following vehicle. The stability condition of the mo...In this paper, we present a new car-following model by taking into account the effects of the traffic interruption probability on the car-following behaviour of the following vehicle. The stability condition of the model is obtained by using the linear stability theory. The modified Korteweg-de Vries （KdV） equation is constructed and solved, and three types of traffic flows in the headway sensitivity space-stable, metastable, and unstable--are classified. Both the analytical and simulation results show that the traffic interruption probability indeed has an influence on driving behaviour, and the consideration of traffic interruption probability in the car-following model could stabilize traffic flow.展开更多
Water flow from an artesian well stopped on December 17, 2007 but recovered when the Wenchuan Ms 8.0 earthquake occurred on May 12, 2008. This well is located 90 km south of the epicenter in an extensional tectonic se...Water flow from an artesian well stopped on December 17, 2007 but recovered when the Wenchuan Ms 8.0 earthquake occurred on May 12, 2008. This well is located 90 km south of the epicenter in an extensional tectonic setting, where similar changes of water level and resistivity were observed at two other nearby sites. Our investigation suggests that this phenomenon was not caused by environmental disturbances, such as drought or borehole-drilling activity, but might be a precursor to the earthquake.展开更多
Revolving parts with complex surface structures are widely used in machinery and mechanical equipment. The ECM process provides its adequacy to cut hard materials with different shapes, and its applications are widely...Revolving parts with complex surface structures are widely used in machinery and mechanical equipment. The ECM process provides its adequacy to cut hard materials with different shapes, and its applications are widely increased, due to its outstanding advantages. In this paper, a new method for machining a convex strips structure on a cylinder by using site directed power interruption（SDPI） in the ECM process is presented. A variable correction value of the power-off time was defined and optimized to obtain the ideal interval for better machining accuracy and stability.The electric field distribution and the simulated convex profiles show that the stray current density can be reduced effectively by using the proposed method. The correction value has an important influence on the machining accuracy. A suitable correction value in the range of 0.6–1.2 s can effectively improve the machining accuracy of the convex strips structure. Experiments were also conducted to verify the proposed method. Results have confirmed that the stray corrosion on the convex strips surface is significantly reduced and the machining accuracy of convex strips structure is remarkably improved by using the proposed method with a suitable correction value in the ECM process. Finally, a convex strip with a height of 2 mm on a thin-wall revolving part was also produced successfully using a correction value of 0.9.展开更多
The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and grow...The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and growth interruption on the electrical properties are investigated by changing the Si-cell temperature, doping time and growth process. It is found that the optimal Si ^-doping concentration （Nd） is about 5.0 x 1012 cm-2 and the use of growth interruption has a dramatic effect on the improvement of electrical properties. The material structure and crystal interface are analyzed by secondary ion mass spectroscopy and high resolution transmission elec- tron microscopy. An InGaAs/InAiAs/InP HEMT device with a gate length of lOOnm is fabricated. The device presents good pinch-off characteristics and the kink-effect of the device is trifling. In addition, the device exhibits fT = 249 GHa and fmax 〉 400 GHz.展开更多
Considering the effects that the probability of traffic interruption and the friction between two lanes have on the car-following behaviour, this paper establishes a new two-lane microscopic car-following model. Based...Considering the effects that the probability of traffic interruption and the friction between two lanes have on the car-following behaviour, this paper establishes a new two-lane microscopic car-following model. Based on this microscopic model, a new macroscopic model was deduced by the relevance relation of microscopic and macroscopic scale parameters for the two-lane traffic flow. Terms related to lane change are added into the continuity equations and velocity dynamic equations to investigate the lane change rate. Numerical results verify that the proposed model can be efficiently used to reflect the effect of the probability of traffic interruption on the shock, rarefaction wave and lane change behaviour on two-lane freeways. The model has also been applied in reproducing some complex traffic phenomena caused by traffic accident interruption.展开更多
Electrochemical impedance spectroscopy (EIS) is widely used in fuel cell impedance analysis. However, for ohmic resistance (R Ω), EIS has some disadvantages such as long test period and complex data analysis with equ...Electrochemical impedance spectroscopy (EIS) is widely used in fuel cell impedance analysis. However, for ohmic resistance (R Ω), EIS has some disadvantages such as long test period and complex data analysis with equivalent circuits. Therefore, the current interruption method is explored to measure the value of RΩ in direct methanol fuel cells (DMFC) at different temperatures and current densities. It is found that RΩ decreases as temperature increase, and decreases initially and then increases as current density increases. These results are consistent with those measured by the EIS technique. In most cases, the ohmic resistances with current interruption (R iR ) are larger than those with EIS (R EIS ), but the difference is small, in the range from –0.848% to 5.337%. The errors of R iR at high current densities are less than those of R EIS . Our results show that the R iR data are reliable and easy to obtain in the measurement of ohmic resistance in DMFC.展开更多
Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid...Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of microgrids.Then,the following works are carried out in the CPS.In the physical layer:1)Regarding trading between microgrids and the load,based on the generalized game theory,an optimal pricing strategy is proposed,which takes into account the interactive relationships among microgrids and transforms the pricing problem into a Nikaido-Isoda function to obtain the optimal prices conveniently;2)Regarding peer-to-peer trading between two microgrids,based on evolutionary game theory and the penalty mechanism,the optimal sale price of the seller is selected with boundary rationality.In the cyber layer,regarding the communication interruption issue existing in pricing(i.e.,the game process),based on the principle of matching the performance of the path with the importance degree of the data,a dynamic regulating method of paths is proposed,i.e.,adopting a new path to re-transmit the interrupted data to the destination.Finally,the effect of the proposed strategies is verified by case studies.展开更多
Traffic interruption phenomena frequently occur with the number of vehicles increasing.To investigate the effect of the traffic interruption probability on traffic flow,a new optimal velocity model is constructed by c...Traffic interruption phenomena frequently occur with the number of vehicles increasing.To investigate the effect of the traffic interruption probability on traffic flow,a new optimal velocity model is constructed by considering the driver anticipation term in the interruption case for car-following theory.Furthermore,the effect of driver anticipation in the interruption case is investigated via linear stability analysis.Also,the MKdV equation is obtained concerning the effect of driver anticipation in the interruption case.Moreover,numerical simulation states that the driver anticipation term in the interruption case contributes to the stability of traffic flow.展开更多
We systematically investigate the influence of growth interruption time on the properties of In As/Ga Sb type-II superlattices(T2SLs) epitaxial materials grown by molecular beam epitaxy(MBE). X-ray diffraction(XRD) an...We systematically investigate the influence of growth interruption time on the properties of In As/Ga Sb type-II superlattices(T2SLs) epitaxial materials grown by molecular beam epitaxy(MBE). X-ray diffraction(XRD) and atomic force microscope(AFM) are used to characterize the material quality and morphology. The full width at half maximum(FWHM) of the XRD 0th satellite peaks ranges from 32″ to 41″, and the root mean square(RMS) roughness on a 5 μm×5 μm scan area is 0.2 nm. Photoluminescence(PL) test is used to reveal the influence of the growth interruption time on the optical property. Grazing incidence X-ray reflectivity(GIXRR) measurements are performed to analyze the roughness of the interface. The interface roughness(0.24 nm) is optimal when the interruption time is 0.5 s. The crystal quality of T2SLs can be optimized with appropriate interruption time by MBE, which is a guide for the material epitaxy of high performance T2SL infrared detector.展开更多
The power system infrastructure, operations and market have gone through radical changes for the last couple of decades. The society has become more dependent to the continuous electric power supply and hence the conc...The power system infrastructure, operations and market have gone through radical changes for the last couple of decades. The society has become more dependent to the continuous electric power supply and hence the concept of electric power reliability has become more significant. At this point, understanding the economic outcomes of power outages is vital and imperative for both utilities and the customers. There are certain methodologies to understand the costs of power interruptions. This paper suggests a novel hybrid method that comprises of customer surveys and direct analytical methods to reach customer specific, objective and reliable results for the industry sector customers. The paper also brings a statistical approach to censor the zero and extreme responses given via the surveys.展开更多
基金Analysis of Lung Compliance Measurement and its Guided Therapeutic Effects in Patients with ARDS Secondary to Severe Multiple Trauma(Project No.:XSD-2023-002)。
文摘In recent years,research on nursing interruptions has been conducted at various levels in emergency departments,intensive care units,hemodialysis centers,operating rooms,and sterilization and supply centers.Nursing interruptions are closely related to adverse nursing events,and interruptions in operating room nursing can significantly impact the success of a patient’s surgery.However,there is a lack of in-depth theoretical research on safety risk assessment and response decision-making by operating room nurses when faced with nursing interruptions.This article reviews the concept,current status,and impact of nursing interruptions in the operating room,analyzes the cognitive level,coping strategies,and negative emotions of operating room nurses,and elaborates on management strategies to provide references for research and management of nursing interruptions in the operating room.
基金supported by Craig H.Neilsen Foundation,Wings for Life Foundation,Canadian Institutes of Health Research,and Fonds de Recherche Québec-Santé(to FB).
文摘Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are incomplete and spare supraspinal pathways,especially those located within the peripheral white matter of the spinal cord,which includes reticulospinal pathways originating from the medullary reticular formation.Whereas there is abundant literature about the motor cortex,its corticospinal pathway,and its capacity to modulate functional recovery after SCI,less is known about the medullary reticular formation and its reticulospinal pathway.
基金Supported by the office of Science and Technology of Xinjiang,No.960505003
文摘AIM： To evaluate the efficacy of interruption of intrauterine infection of HBV with HBIG in pregnant women with positive HBeAg and HBsAg.METHODS： A prospective randomized controlled trial was adopted. Sixty cases with positive HBeAg and HBsAg were coincident with the criteria of inclusion, and 8 cases were excluded. Fifty-two cases were analyzed （28 cases in trial group and 24 in control group）. All cases in trial group received 200 IU HBIG intravenously every 4 wk for 3 times from the 28^th wk. The cases of control group received placebo in the same way. All pregnant women were detected for HBeAg and HBV-DNA at the beginning of the trial and end of the trial （delivery）. The cord blood of all newborns were collected for detecting HBeAg and HBV-DNA simultaneously.RESULTS： For investigation of HBeAg of newborns in trial group, 6 of 28 cases of newborns had positive HBeAg, the HBeAg positive rate being 21.4%, the total rate of 95% CI being 8%-41%. In control group, 19 of 24 cases of newborns had positive HBeAg, HBeAg positive rate was 79.2%, the rate of 95%CI being 5%-93%. By statistical analysis, 2= 17.26, P 〈 0.01, RR = 0.27, 95% CI （6.3 × 10^-6, 8.6 × 10^-5）. For investigation of HBV-DNA of newborns in trial group, 7 of 28 cases of newborns had positive HBV-DNA, HBV-DNA positive rate being 25%, the total rate of 95% CI being 11%-45%. In control group, 20 of 24 cases of newborns had positive HBV-DNA, HBV-DNA positive rate was 83.3%, the total rate of 95% CI being 63%-95%. By statistical analysis, X^2 = 17.62, P 〈 0.01, RR = 0.30, 95% CI （1.5 × 10^-5, 1.7× 10^-4）. The results indicated that there was significant difference in HBeAg positive rate and HBV-DNA positive rate of newborns between the two groups. In trial group, 7 of 28 newborns had HBV-DNA positive, but the HBV-DNA load of newborns was lower than that of their mothers. In control group, 20 of 24 newborns still had HBV-DNA positive, and the HBV-DNA load of newborns was close to those of their mothers. Statistical analysis indicated that there was no significant difference in HBV- DNA load between postnatal women without HBIG intervention and their filial generations （T = 81.5, P 〉 0.1）. CONCLUSION： It is effective and safe to prevent intrauterine infection of HBV with HBIG from the 28^th wk in pregnant women with positive HBeAg and HBsAg. In clinical application, those pregnant women with negative HBeAg and positive HBV-DNA also need to be interrupted by HBIG.
基金Paper extracted from The New Xiangya Talent Projects of the Third Xiangya Hospital of Central South University(NO:JY201720).
文摘Objectives:To explore the knowledge,attitude and practice of Chinese nurses regarding nursing interruptions and related factors.Methods:A total of 6,400 nurses from 31 hospitals in China were investigated by using the Knowledge,Attitude and Practice(KAP)Questionnaire of Nursing Interruptions.The questionnaire consists of three dimensions,knowledge,attitude and practice,containing 10,9 and 7 items,with full score of 50,45 and 28,respectively.Results:The mean overall KAP score regarding nursing interruptions of Chinese nurses was 74.05±16.65(range:26-123),with scores for the knowledge,attitude,and practice component being 21.74±9.80,34.83±6.98,and 17.49±4.97,respectively.Among the nurses,70.8%of them experienced an average level of KAP toward nursing interruptions while 15.5%were at a poor level.The knowledge,attitude,and practice of nursing interruptions were better in chief nurses,managers,nurses with a master degree or above,nurses ever received training,and nurses with a strong agreement to leadership compared to nurses in other groups(P<0.05).In addition,employment type,professional title,position,standardized training and leaders'attention were predictors of KAP in nurses.Conclusion:Chinese nurses have a moderate level of KAP regarding nursing interruptions.Leaders'attention,standardized training,position,professional title and employment type could predict nurses'KAP state of nursing interruptions.Thus,a targeted training program should be implemented for clinical nurses by nursing leaders,with a particular focus on feasibility and professionalism.
基金Supported by The Innovative Talent Support Program of The Institution of Higher Learning in Liaoning Province,No.2018-478The Innovative Talents of Science and Technology Support Program of Young and Middle People of Shenyang,No.RC170446.
文摘Pituitary stalk interruption syndrome(PSIS)is a rare congenital abnormality characterized by thinning or disappearance of the pituitary stalk,hypoplasia of the anterior pituitary and an ectopic posterior pituitary.Although the etiology of PSIS is still unclear,gene changes and perinatal adverse events such as breech delivery may play important roles in the pathogenesis of PSIS.PSIS can cause multiple hormone deficiencies,such as growth hormone,which then cause a series of changes in the human body.On the one hand,hormone changes affect growth and development,and on the other hand,they could affect human metabolism and subsequently the liver resulting in nonalcoholic fatty liver disease(NAFLD).Under the synergistic effect of multiple mechanisms,the progression of NAFLD caused by PSIS is faster than that due to other causes.Therefore,in addition to early identification of PSIS,timely hormone replacement therapy and monitoring of relevant hormone levels,clinicians should routinely assess the liver function while managing PSIS.
基金supported by the National Natural Science Foundation of China (Grant Nos 70701002 and 70521001)the National Basic Research Program of China (Grant No 2006CB705503)the Research Grants Council of the Hong Kong Special Administrative Region of China (Grant No HKU7187/05E)
文摘In this paper, we present a new car-following model by taking into account the effects of the traffic interruption probability on the car-following behaviour of the following vehicle. The stability condition of the model is obtained by using the linear stability theory. The modified Korteweg-de Vries （KdV） equation is constructed and solved, and three types of traffic flows in the headway sensitivity space-stable, metastable, and unstable--are classified. Both the analytical and simulation results show that the traffic interruption probability indeed has an influence on driving behaviour, and the consideration of traffic interruption probability in the car-following model could stabilize traffic flow.
基金supported by the National Natural Science Foundation ofChina(40930637)Basic Science Research Special Item of the Instituteof Geology,China Earthquake Administration(DF-IGCEA-0608210)Special Research Program of China Earthquake Administration(200808079)
文摘Water flow from an artesian well stopped on December 17, 2007 but recovered when the Wenchuan Ms 8.0 earthquake occurred on May 12, 2008. This well is located 90 km south of the epicenter in an extensional tectonic setting, where similar changes of water level and resistivity were observed at two other nearby sites. Our investigation suggests that this phenomenon was not caused by environmental disturbances, such as drought or borehole-drilling activity, but might be a precursor to the earthquake.
基金supports provided by the State Key Program of the National Natural Science Foundation of China(No.51535006)Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology of China
文摘Revolving parts with complex surface structures are widely used in machinery and mechanical equipment. The ECM process provides its adequacy to cut hard materials with different shapes, and its applications are widely increased, due to its outstanding advantages. In this paper, a new method for machining a convex strips structure on a cylinder by using site directed power interruption（SDPI） in the ECM process is presented. A variable correction value of the power-off time was defined and optimized to obtain the ideal interval for better machining accuracy and stability.The electric field distribution and the simulated convex profiles show that the stray current density can be reduced effectively by using the proposed method. The correction value has an important influence on the machining accuracy. A suitable correction value in the range of 0.6–1.2 s can effectively improve the machining accuracy of the convex strips structure. Experiments were also conducted to verify the proposed method. Results have confirmed that the stray corrosion on the convex strips surface is significantly reduced and the machining accuracy of convex strips structure is remarkably improved by using the proposed method with a suitable correction value in the ECM process. Finally, a convex strip with a height of 2 mm on a thin-wall revolving part was also produced successfully using a correction value of 0.9.
基金Supported by the National Natural Science Foundation of China under Grant No 61434006
文摘The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and growth interruption on the electrical properties are investigated by changing the Si-cell temperature, doping time and growth process. It is found that the optimal Si ^-doping concentration （Nd） is about 5.0 x 1012 cm-2 and the use of growth interruption has a dramatic effect on the improvement of electrical properties. The material structure and crystal interface are analyzed by secondary ion mass spectroscopy and high resolution transmission elec- tron microscopy. An InGaAs/InAiAs/InP HEMT device with a gate length of lOOnm is fabricated. The device presents good pinch-off characteristics and the kink-effect of the device is trifling. In addition, the device exhibits fT = 249 GHa and fmax 〉 400 GHz.
基金Project supported by the National High Tech Research and Development Program of China (Grant No. 511-0910-1031)
文摘Considering the effects that the probability of traffic interruption and the friction between two lanes have on the car-following behaviour, this paper establishes a new two-lane microscopic car-following model. Based on this microscopic model, a new macroscopic model was deduced by the relevance relation of microscopic and macroscopic scale parameters for the two-lane traffic flow. Terms related to lane change are added into the continuity equations and velocity dynamic equations to investigate the lane change rate. Numerical results verify that the proposed model can be efficiently used to reflect the effect of the probability of traffic interruption on the shock, rarefaction wave and lane change behaviour on two-lane freeways. The model has also been applied in reproducing some complex traffic phenomena caused by traffic accident interruption.
基金Supported by the National High Technology Research and Development Program of China （2007AA05Z150） the National Natural Science Foundation of China （50911140287 50973055）
文摘Electrochemical impedance spectroscopy (EIS) is widely used in fuel cell impedance analysis. However, for ohmic resistance (R Ω), EIS has some disadvantages such as long test period and complex data analysis with equivalent circuits. Therefore, the current interruption method is explored to measure the value of RΩ in direct methanol fuel cells (DMFC) at different temperatures and current densities. It is found that RΩ decreases as temperature increase, and decreases initially and then increases as current density increases. These results are consistent with those measured by the EIS technique. In most cases, the ohmic resistances with current interruption (R iR ) are larger than those with EIS (R EIS ), but the difference is small, in the range from –0.848% to 5.337%. The errors of R iR at high current densities are less than those of R EIS . Our results show that the R iR data are reliable and easy to obtain in the measurement of ohmic resistance in DMFC.
基金This work was supported in part by the National Key Research and Development Program of China(2018YFA0702200)the National Natural Science Foundation of China(61933005,61833008)+6 种基金the Natural Science Foundation of Jiangsu Province of China(BK20220395)the Leading Technology Foundation Research Project of Jiangsu Province(BK20202011)the Natural Science Foundation of Jiangsu Universities(22KJB470024)Jiangsu Provincial Key Research and Development Program(BE2020001)Natural Science Foundation of Hebei Province of China(E2020203139)Natural Science Foundation of Nanjing University of Posts and Telecommunications(NY222032)the National Research Foundation of Korea(2020R1A2B5B02002002).
文摘Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of microgrids.Then,the following works are carried out in the CPS.In the physical layer:1)Regarding trading between microgrids and the load,based on the generalized game theory,an optimal pricing strategy is proposed,which takes into account the interactive relationships among microgrids and transforms the pricing problem into a Nikaido-Isoda function to obtain the optimal prices conveniently;2)Regarding peer-to-peer trading between two microgrids,based on evolutionary game theory and the penalty mechanism,the optimal sale price of the seller is selected with boundary rationality.In the cyber layer,regarding the communication interruption issue existing in pricing(i.e.,the game process),based on the principle of matching the performance of the path with the importance degree of the data,a dynamic regulating method of paths is proposed,i.e.,adopting a new path to re-transmit the interrupted data to the destination.Finally,the effect of the proposed strategies is verified by case studies.
基金the National Natural Science Foundation of China(Grant Nos.61963008 and 61673168)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2018GXNSFAA281274)+1 种基金the Doctor Scientific Research Startup Project Foundation of Guangxi Normal University,China(Grant No.2018BQ007)the Innovation-Driven Development Special Fund Project of Guangxi Zhuang Autonomous Region,China(Grant No.GUIKEAA19254034).
文摘Traffic interruption phenomena frequently occur with the number of vehicles increasing.To investigate the effect of the traffic interruption probability on traffic flow,a new optimal velocity model is constructed by considering the driver anticipation term in the interruption case for car-following theory.Furthermore,the effect of driver anticipation in the interruption case is investigated via linear stability analysis.Also,the MKdV equation is obtained concerning the effect of driver anticipation in the interruption case.Moreover,numerical simulation states that the driver anticipation term in the interruption case contributes to the stability of traffic flow.
基金supported by the Beijing Scholars Program (No.74A2111113)the Research Project of Beijing Education Committee (No.KM202111232019)+2 种基金the National Natural Science Foundation of China (No.62205029)the Young Elite Scientist Sponsorship Program by the China Association for Science and Technology (No.YESS20200146)the Beijing Natural Science Foundation (No.4202027)。
文摘We systematically investigate the influence of growth interruption time on the properties of In As/Ga Sb type-II superlattices(T2SLs) epitaxial materials grown by molecular beam epitaxy(MBE). X-ray diffraction(XRD) and atomic force microscope(AFM) are used to characterize the material quality and morphology. The full width at half maximum(FWHM) of the XRD 0th satellite peaks ranges from 32″ to 41″, and the root mean square(RMS) roughness on a 5 μm×5 μm scan area is 0.2 nm. Photoluminescence(PL) test is used to reveal the influence of the growth interruption time on the optical property. Grazing incidence X-ray reflectivity(GIXRR) measurements are performed to analyze the roughness of the interface. The interface roughness(0.24 nm) is optimal when the interruption time is 0.5 s. The crystal quality of T2SLs can be optimized with appropriate interruption time by MBE, which is a guide for the material epitaxy of high performance T2SL infrared detector.
文摘The power system infrastructure, operations and market have gone through radical changes for the last couple of decades. The society has become more dependent to the continuous electric power supply and hence the concept of electric power reliability has become more significant. At this point, understanding the economic outcomes of power outages is vital and imperative for both utilities and the customers. There are certain methodologies to understand the costs of power interruptions. This paper suggests a novel hybrid method that comprises of customer surveys and direct analytical methods to reach customer specific, objective and reliable results for the industry sector customers. The paper also brings a statistical approach to censor the zero and extreme responses given via the surveys.
