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Cloud Top Pressure Retrieval Using Polarized and Oxygen A-band Measurements from GF5 and PARASOL Satellites
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作者 Lesi WEI Huazhe SHANG +6 位作者 Jian XU Chong SHI Gegen TANA Kefu CHAO Shanhu BAO Liangfu CHEN Husi LETU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期680-700,共21页
Cloud top pressure(CTP)is one of the critical cloud properties that significantly affects the radiative effect of clouds.Multi-angle polarized sensors can employ polarized bands(490 nm)or O_(2)A-bands(763 and 765 nm)t... Cloud top pressure(CTP)is one of the critical cloud properties that significantly affects the radiative effect of clouds.Multi-angle polarized sensors can employ polarized bands(490 nm)or O_(2)A-bands(763 and 765 nm)to retrieve the CTP.However,the CTP retrieved by the two methods shows inconsistent results in certain cases,and large uncertainties in low and thin cloud retrievals,which may lead to challenges in subsequent applications.This study proposes a synergistic algorithm that considers both O_(2)A-bands and polarized bands using a random forest(RF)model.LiDAR CTP data are used as the true values and the polarized and non-polarized measurements are concatenated to train the RF model to determine CTP.Additionally,through analysis,we proposed that the polarized signal becomes saturated as the cloud optical thickness(COT)increases,necessitating a particular treatment for cases where COT<10 to improve the algorithm's stability.The synergistic method was then applied to the directional polarized camera(DPC)and Polarized and Directionality of the Earth’s Reflectance(POLDER)measurements for evaluation,and the resulting retrieval accuracy of the POLDER-based measurements(RMSEPOLDER=205.176 hPa,RMSEDPC=171.141 hPa,R^(2)POLDER=0.636,R^(2)DPC=0.663,respectively)were higher than that of the MODIS and POLDER Rayleigh pressure measurements.The synergistic algorithm also showed good performance with the application of DPC data.This algorithm is expected to provide data support for atmosphere-related fields as an atmospheric remote sensing algorithm within the Cloud Application for Remote Sensing,Atmospheric Radiation,and Updating Energy(CARE)platform. 展开更多
关键词 atmospheric remote sensing cloud top pressure multi-angle polarized O_(2)A-band GF-5/DPC PARASOL/POLDER-3
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Driving pressure:A useful tool for reducing postoperative pulmonary complications
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作者 Domenico Posa Fabio Sbaraglia +1 位作者 Giuliano Ferrone Marco Rossi 《World Journal of Critical Care Medicine》 2024年第3期91-94,共4页
The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics.Therefore,raising clinicians’awareness of the potential risk of ventilator-ind... The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics.Therefore,raising clinicians’awareness of the potential risk of ventilator-induced lung injury(VILI)is mandatory.Driving pressure is a useful tool for reducing lung complications in patients with acute respiratory distress syndrome and those undergoing elective surgery.Driving pressure has been most extensively studied in the context of single-lung ventilation during thoracic surgery.However,the awareness of association of VILI risk and patient positioning(prone,beach-chair,parkbench)and type of surgery must be raised. 展开更多
关键词 Ventilator-induced lung injury Protective ventilation Driving pressure Mechanical ventilation Surgery room Single-lung ventilation Operative room SURGERY
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Prediction and optimization of flue pressure in sintering process based on SHAP
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作者 Mingyu Wang Jue Tang +2 位作者 Mansheng Chu Quan Shi Zhen Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期346-359,共14页
Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley a... Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment measures.First,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction model.The effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment conditions.The operating parameter combination was then pushed.The flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect. 展开更多
关键词 sintering process flue pressure shapley additive explanation PREDICTION OPTIMIZATION
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A Flexible Smart Healthcare Platform Conjugated with Artificial Epidermis Assembled by Three‑Dimensionally Conductive MOF Network for Gas and Pressure Sensing
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作者 Qingqing Zhou Qihang Ding +8 位作者 Zixun Geng Chencheng Hu Long Yang Zitong Kan Biao Dong Miae Won Hongwei Song Lin Xu Jong Seung Kim 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期601-620,共20页
The rising flexible and intelligent electronics greatly facilitate the noninvasive and timely tracking of physiological information in telemedicine healthcare.Meticulously building bionic-sensitive moieties is vital f... The rising flexible and intelligent electronics greatly facilitate the noninvasive and timely tracking of physiological information in telemedicine healthcare.Meticulously building bionic-sensitive moieties is vital for designing efficient electronic skin with advanced cognitive functionalities to pluralistically capture external stimuli.However,realistic mimesis,both in the skin’s three-dimensional interlocked hierarchical structures and synchronous encoding multistimuli information capacities,remains a challenging yet vital need for simplifying the design of flexible logic circuits.Herein,we construct an artificial epidermal device by in situ growing Cu_(3)(HHTP)_(2) particles onto the hollow spherical Ti_(3)C_(2)T_(x) surface,aiming to concurrently emulate the spinous and granular layers of the skin’s epidermis.The bionic Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2) exhibits independent NO_(2) and pressure response,as well as novel functionalities such as acoustic signature perception and Morse code-encrypted message communication.Ultimately,a wearable alarming system with a mobile application terminal is self-developed by integrating the bimodular senor into flexible printed circuits.This system can assess risk factors related with asthmatic,such as stimulation of external NO_(2) gas,abnormal expiratory behavior and exertion degrees of fingers,achieving a recognition accuracy of 97.6%as assisted by a machine learning algorithm.Our work provides a feasible routine to develop intelligent multifunctional healthcare equipment for burgeoning transformative telemedicine diagnosis. 展开更多
关键词 Ti_(3)C_(2)T_(x)@Cu_(3)(HHTP)_(2)composites NO_(2)/pressure flexible sensors Health-monitoring Machine learning
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p型TOPCon结构的隧穿氧化和钝化工艺研究
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作者 高嘉庆 屈小勇 +5 位作者 吴翔 郭永刚 王永冈 汪梁 谭新 杨鑫泽 《人工晶体学报》 北大核心 2025年第1期133-138,共6页
为深入研究p型TOPCon结构的制备工艺和钝化性能,本文通过实验研究了隧穿氧化层生长过程中氧气流量、氧化温度和氧化时间对氧化层质量的影响,以及在不同硼扩散温度下p-poly的钝化性能和方块电阻。实验结果表明,氧气流量达到15 slm(标准... 为深入研究p型TOPCon结构的制备工艺和钝化性能,本文通过实验研究了隧穿氧化层生长过程中氧气流量、氧化温度和氧化时间对氧化层质量的影响,以及在不同硼扩散温度下p-poly的钝化性能和方块电阻。实验结果表明,氧气流量达到15 slm(标准升每分钟)以上,p-poly的隐开路电压平均值达到730 mV,暗饱和电流密度低至3.5 fA/cm^(2)。氧化温度和时间分别达到620℃和30 min时,p-poly的隐开路电压可提升至735 mV;随着氧化温度的提高或者氧化时间的延长,p-poly的隐开路电压趋于稳定。硼扩散温度为960℃时,p-poly的方块电阻保持在132Ω/,硅基体中的掺杂结深为0.25μm,获得了良好的钝化性能。本文所确定的工艺参数可制备出具有良好钝化性能的p-poly结构,对未来p型TOPCon结构在高效晶硅电池上的产业化应用提供了一定的数据支撑。 展开更多
关键词 p型topCon结构 低压化学气相沉积 钝化质量 隐开路电压 暗饱和电流密度 太阳能电池
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Coupling effects of coal pillars of thick coal seams in large-space stopes and hard stratum on mine pressure 被引量:11
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作者 Xia Binwei Jia Jinlong +2 位作者 Yu Bin Zhang Xuan Li Xiaolong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期965-972,共8页
Concerning the issue of mine pressure behaviors occurred in fully mechanized caving mining of thick coal seams beneath hard stratum in Datong Mining Area, combined with thin and thick plate theory, the paper utilizes ... Concerning the issue of mine pressure behaviors occurred in fully mechanized caving mining of thick coal seams beneath hard stratum in Datong Mining Area, combined with thin and thick plate theory, the paper utilizes theoretical analysis, similar experiments, numerical simulations and field tests to study the influence of remaining coal pillars in Jurassic system goaf on hard stratum fractures, as well as mine pressure behaviors under their coupling effects. The paper concludes the solution formula of initial fault displacement in hard stratum caused by remaining coal pillars. Experiments prove that coupling effects can enhance mine pressure behaviors on working faces. When inter-layer inferior key strata fractures, mine pressure phenomenon such as significant roof weighting steps and increasing resistance in support.When inter-layer superior key strata fractures, the scope of overlying strata extends to Jurassic system goaf, dual-system stopes cut through, and remaining coal pillars lose stability. As a result, the bottom inferior key strata also lose stability. It causes huge impacts on working face, and the second mine pressure behaviors. These phenomena provide evidence for research on other similar mine strata pressure behaviors occurred in dual-system mines with remaining coal pillars. 展开更多
关键词 Dual system CAVING Coal PILLAR HARD rock Broken INSTABILITY Mining pressure REVEAL
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Intraocular pressure with rebound tonometry and effects of topical intraocular pressure reducing medications in guinea pigs 被引量:2
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作者 Yue Di Xiu-Mei Luo +1 位作者 Tong Qiao Na Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第2期186-190,共5页
AIM: To investigate the intraocular pressure(IOP) of adult guinea pig eyes with rebound tonometry(RBT),and assess the effects of four distinctive topical IOP reducing medications including Carteolol,Brimonidine,B... AIM: To investigate the intraocular pressure(IOP) of adult guinea pig eyes with rebound tonometry(RBT),and assess the effects of four distinctive topical IOP reducing medications including Carteolol,Brimonidine,Brinzolamide and Latanoprost.METHODS: The IOPs of twenty-four 12-week-old guinea pigs(48 eyes) were measured every two hours in one day with RBT as baselines.All the animals were then divided into four groups(Carteolol,Brimonidine,Brinzolamide and Latanaprost groups,n=6).The IOPs were measured and compared to the baseline 1,2,3,5,7,9,15 and 24 h after treatment.RESULTS: The mean baseline IOP of 24 guinea pigs(48 eyes) was 10.3±0.36 mm Hg(6-13 mm Hg) and no binocular significant differences of IOPs were observed(t=1.76,P〉0.05).No significant difference of IOP in Carteolol group at each time point was observed before and after treatment(t=1.48,P〉0.05).In Brimonidine group,IOP was 2.2±1.9 mm Hg lower than the baseline after one hour(t=3.856,P=0.003) and lasted for one hour.In Brinzolamide group,IOP was 1.4±1.1 mm Hg lower than the baseline after one hour(t=4.53,P=0.001) and lasted for 7h and the IOP declined most at 3h.In Latanaprost group,IOP was 2.1±1.3 mm Hg lower than the baseline after one hour(t=6.11,P=0.001) and lasted for one hour.CONCLUSION: The IOP of guinea pig eyes is relatively stable compared to human eyes.In four reducing IOP medications,no significant effect of Carteolol is observed.Brinzolamide has the longest duration,while the Brimonidine has the shortest duration and the maximum level of treatment. 展开更多
关键词 guinea pig intraocular pressure CARTEOLOL Brinzolamide BRIMONIDINE LATANOPROST
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STUDY ON VARIATION OF SETTING AND STOPPING PRESSURES OF SAFETY VALVE WITH STRUCTURAL MODIFICATION 被引量:1
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作者 Lee Jinho Kwangzin Valve Industrial Co ,Ltd,Korea Kim Harkbong Kim Moonsang School of Aerospace and Mechanical Engineering,Hankook Aviation University,Korea 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期127-138,共12页
The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plant... The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plants,and piping Setting and stopping pressures of a safety valve, p set and p sto ,are traditionally adjusted with a fine tuning of seat ring and valve ring heights, h sr and h vr However, it is not easy to achieve the proper setting and stopping pressures of a safety valve in practice The depth of inside and outside grooves in a valve, d i and d o are modified and their effects on setting and stopping pressures of a safety vlave are tested The most appropriate values appear 1 0 mm in d i and 0 5~1 0 mm in d o,respectively The valve ring height, h vr ,shows that the best results can be achieved at 2 3 mm for setting pressures of 0 1~0 4 MPa and 1 0 mm for setting pressures of 0 5~1 0 MPa The stopping pressures increases with the increase of seat ring height, h sr , upto certain h sr value and then becomes independent to the seat ring height This implies that there exists the optimum h sr ,which provides the largest flow rate and the proper stopping pressure Stopping pressures of a safety valve are adjusted with the seat ring and valve ring heights This study,however,demonstrated that the modification of value grooves also changes setting and stopping pressures of a safety valve Therefore,the proper selection in dimensions of the inside and outside grooves should be considered for the safety valve design 展开更多
关键词 Safety valve Compressive flow Isentropic flow theory Isentropic comressibility theory Setting pressure Stopping pressure Continuity equation Momentum equation
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Effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome 被引量:5
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作者 Mehri Najafi Sani Hamid Reza Kianifar +1 位作者 Abdolrazagh Kianee Gholamreza Khatami 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第15期2427-2431,共5页
AIM: To study the effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome, METHODS: Garlic powder in a capsule form was given to 15 children with hepatopulmonary syndrome (confir... AIM: To study the effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome, METHODS: Garlic powder in a capsule form was given to 15 children with hepatopulmonary syndrome (confirmed by contrast echocardiography) at the dosage of 1 g/1.73 m^2 per day. Patients were evaluated clinically and by arterial blood gas every four weeks. RESULTS: The garlic capsule was administered to 15 patients with hepatopulmonary syndrome. There were 10 boys and 5 girls with a mean age of 9.4 ± 3.9 years. The underlying problems were biliary tract atresia (4 patients), autoimmune hepatitis (4 patients), cryptogenic cirrhosis (4 patients) and presinusoidal portal hypertension (3 patients). Eight patients (53.3%) showed an increase of 10 mmHg in their mean arterial oxygen pressure. The baseline PaO2 was 65.6 ± 12.1 mmHg in the responder group and 47.1 ± 11.2 mmHg in nonresponder group. At the end of treatment the mean PaO2 in responders and non-responders was 92.2 ± 7.75 mmHg and 47.5 ± 11.87 mmHg, respectively (P 〈 0.01). CONCLUSION: Garlic may increase oxygenation and improve dyspnea in children with hepatopulmonary syndrome. 展开更多
关键词 Hepatopulmonary syndrome GARLIC Arterial oxygen pressure PEDIATRIC
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Tono-pen measurement of intraocular pressure under topical anaesthesia in full term normal newborns 被引量:1
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作者 Sagili Chandrasekhara Reddy Rosnita Alias 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第1期92-94,共3页
AIM: Tono-pen measurement of intraocular pressure(IOP) under topical anaesthesia in full term normal newborns. ·METHODS: The IOP measurements were taken using Tono-pen XL tonometer under topical anaesthesia in 15... AIM: Tono-pen measurement of intraocular pressure(IOP) under topical anaesthesia in full term normal newborns. ·METHODS: The IOP measurements were taken using Tono-pen XL tonometer under topical anaesthesia in 150 newborns(300 eyes) within 24h after birth,over a period of three months,in a university hospital. Gender,gestation period,mode of delivery and birth weight of newborns were noted from medical records. ·RESULTS: There were 70 males and 80 females. All babies were Malays. The IOP measurements were taken between 12 and 24h after birth. The gestation period of babies ranged between 37 and 41 weeks; 118 babies were delivered by spontaneous vaginal delivery and 32 by caesarian section. The birth weight of babies ranged between 2.1 and 4.3kg. The mean IOP of 300 eyes was 15.99±2.79mmHg(range 8-22). There was no statistically significant difference of mean IOP and gender,laterality of eye,type of delivery,gestation age,or birth weight of newborns. ·CONCLUSION: The IOP in full term normal newborns was 16mmHg. Tono-Pen appears to be ideal instrument for taking IOP in newborns because of its small size and easy handling. 展开更多
关键词 intraocular pressure NEWBORN Tono-pen
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DISTRIBUTION OF ACTIVE EARTH PRESSURE OF RETAINING WALL WITH WALL MOVEMENT OF ROTATION ABOUT TOP 被引量:1
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作者 王元战 唐照评 郑斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第7期761-767,共7页
Based on the Coulomb's theory that the earth pressure against the back of a retaining wall is due to the thrust exerted by the sliding wedge of soil from the back of the wall to a plane which passes through the bo... Based on the Coulomb's theory that the earth pressure against the back of a retaining wall is due to the thrust exerted by the sliding wedge of soil from the back of the wall to a plane which passes through the bottom edge of the wall and has an inclination equal to the angle of θ, the theoretical answers to the unit earth pressure, the resultant earth pressure and the point of application of the resultant earth pressure on a retaining wall were obtained for the wall movement mode of rotation about top. The comparisons were made among the formula presented here, the formula for the wall movement mode of translation, the Coulomb's formula and some experimental observations. It is demonstrated that the magnitudes of the resultant earth pressures for the wall movement mode of rotation about top is equal to that determined by the formula for the wall movement mode of translation and the Coulomb's theory. But the distribution of the earth pressure and the points of application of the resultant earth pressures have significant difference. 展开更多
关键词 retaining wall rotation about top active earth pressure DISTRIBUTION point of application
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Automated postoperative blood pressure control 被引量:1
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作者 Hang ZHENG Kuanyi ZHU 《控制理论与应用(英文版)》 EI 2005年第3期207-212,共6页
It is very important to maintain the level of mean arterial pressure (MAP). The MAP control is applied in many clinical situations, including limiting bleeding during cardiac surgery and promoting healing for patien... It is very important to maintain the level of mean arterial pressure (MAP). The MAP control is applied in many clinical situations, including limiting bleeding during cardiac surgery and promoting healing for patient' s post-surgery. This paper presents a fuzzy controller-based multiple-model adaptive control system for postoperative blood pressure management. Multiple-model adaptive control (MMAC) algorithm is used to identify the patient model, and it is a feasible system identification method even in the presence of large noise. Fuzzy control (FC) method is used to design controller bank. Each fuzzy controller in the controller bank is in fact a nonlinear proportional-integral (PI) controller,whose proportional gain and integral gain are adjusted continuously according to error and rate of change of error of the plant output, resulting in better dynamic and stable control performance than the regular PI controller, especially when a nonlinear process is involved. For demonstration, a nonlinear, pulsatile-flow patient model is used for simulation, and the results show that the adaptive control system can effectively handle the changes in patient's dynamics and provide satisfactory performance in regulation of blood pressure of hypertension patients. 展开更多
关键词 Multiple-model adaptive control Fuzzy control Blood pressure control Cardiovascular modeling
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Blood Pressure and Heart Rate Measurements Using Photoplethysmography with Modified LRCN 被引量:1
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作者 Chih-Ta Yen Cheng-Hong Liao 《Computers, Materials & Continua》 SCIE EI 2022年第4期1973-1986,共14页
In this study,single-channel photoplethysmography(PPG)signals were used to estimate the heart rate(HR),diastolic blood pressure(DBP),and systolic blood pressure(SBP).A deep learning model was proposed using a long-ter... In this study,single-channel photoplethysmography(PPG)signals were used to estimate the heart rate(HR),diastolic blood pressure(DBP),and systolic blood pressure(SBP).A deep learning model was proposed using a long-term recurrent convolutional network(LRCN)modified from a deep learning algorithm,the convolutional neural network model of the modified inception deep learning module,and a long short-term memory network(LSTM)to improve the model’s accuracy of BP and HR measurements.The PPG data of 1,551 patients were obtained from the University of California Irvine Machine Learning Repository.How to design a filter of PPG signals and how to choose the loss functions for deep learning model were also discussed in the study.Finally,the stability of the proposed model was tested using a 10-fold cross-validation,with an MAE±SD of 2.942±5.076 mmHg for SBP,1.747±3.042 mmHg for DBP,and 1.137±2.463 bpm for the HR.Compared with its existing counterparts,the model entailed less computational load and was more accurate in estimating SBP,DBP,and HR.These results established the validity of the model. 展开更多
关键词 Photoplethysmography(PPG)signal deep learning blood pressure systolic blood pressure(SBP) diastolic blood pressure(DBP) heart rate(HR)
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Numerical simulation and analysis of underground pressure in the 101 fully-mechanized top coal caving face of the Tingnan Coalmine 被引量:2
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作者 LI Shu-gang PAN Hong-yu +2 位作者 KONG Ting-ting ZHANG Zhi-ming WANG Hong-tao 《Journal of Coal Science & Engineering(China)》 2009年第1期28-32,共5页
The forms of roof break,roof fall,and effects of the region scope in a fully mechanizedtop-coal caving (FMTC) face of the 101 fully-mechanized top coal caving face ofthe Tingnan Coalmine were analyzed by UDEC and FLAC... The forms of roof break,roof fall,and effects of the region scope in a fully mechanizedtop-coal caving (FMTC) face of the 101 fully-mechanized top coal caving face ofthe Tingnan Coalmine were analyzed by UDEC and FLAC^(3D) software.The analysis resultconfirms the phenomenon of roof falling,roof-off-strata,roof breaking,first weighting,periodicweighting and stress concentration,redistributions of surrounding rock and so on.Itprovides the gist to analyze the law of roof movement,characteristic of confining pressure,and to determine the formative structure forms of the immediate roof and main roof duringthe caving process.These results and the underground pressure observation results are inagreement. 展开更多
关键词 Tingnan Coalmine underground pressure numerical simulation
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A Deep Learning-Based Continuous Blood Pressure Measurement by Dual Photoplethysmography Signals 被引量:1
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作者 Chih-Ta Yen Sheng-Nan Chang +1 位作者 Liao Jia-Xian Yi-Kai Huang 《Computers, Materials & Continua》 SCIE EI 2022年第2期2937-2952,共16页
This study proposed a measurement platform for continuous blood pressure estimation based on dual photoplethysmography(PPG)sensors and a deep learning(DL)that can be used for continuous and rapid measurement of blood ... This study proposed a measurement platform for continuous blood pressure estimation based on dual photoplethysmography(PPG)sensors and a deep learning(DL)that can be used for continuous and rapid measurement of blood pressure and analysis of cardiovascular-related indicators.The proposed platform measured the signal changes in PPG and converted them into physiological indicators,such as pulse transit time(PTT),pulse wave velocity(PWV),perfusion index(PI)and heart rate(HR);these indicators were then fed into the DL to calculate blood pressure.The hardware of the experiment comprised 2 PPG components(i.e.,Raspberry Pi 3 Model B and analog-todigital converter[MCP3008]),which were connected using a serial peripheral interface.The DL algorithm converted the stable dual PPG signals acquired from the strictly standardized experimental process into various physiological indicators as input parameters and finally obtained the systolic blood pressure(SBP),diastolic blood pressure(DBP)and mean arterial pressure(MAP).To increase the robustness of the DL model,this study input data of 100 Asian participants into the training database,including those with and without cardiovascular disease,each with a proportion of approximately 50%.The experimental results revealed that the mean absolute error and standard deviation of SBP was 0.17±0.46 mmHg.The mean absolute error and standard deviation of DBP was 0.27±0.52 mmHg.The mean absolute error and standard deviation of MAP was 0.16±0.40 mmHg. 展开更多
关键词 Deep learning(DL) blood pressure continuous non-invasive blood pressure measurement photoplethysmography(PGG)
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High-pressure study of topological semimetals XCd_(2)Sb_(2)(X=Eu and Yb) 被引量:1
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作者 Chuchu Zhu Hao Su +7 位作者 Erjian Cheng Lin Guo Binglin Pan Yeyu Huang Jiamin Ni Yanfeng Guo Xiaofan Yang Shiyan Li 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期65-70,共6页
Topological materials have aroused great interest in recent years,especially when magnetism is involved.Pressure can effectively tune the topological states and possibly induce superconductivity.Here we report the hig... Topological materials have aroused great interest in recent years,especially when magnetism is involved.Pressure can effectively tune the topological states and possibly induce superconductivity.Here we report the high-pressure study of topological semimetals XCd_(2)Sb_(2)(X=Eu and Yb),which have the same crystal structure.In antiferromagnetic(AFM)Weyl semimetal EuCd_(2)Sb_(2),the Néel temperature(TN)increases from 7.4 K at ambient pressure to 50.9 K at 14.9 GPa.When pressure is above 14.9 GPa,the AFM peak of resistance disappears,indicating a non-magnetic state.In paramagnetic Dirac semimetal candidate YbCd_(2)Sb_(2),pressure-induced superconductivity appears at 1.94 GPa,then Tc reaches to a maximum of 1.67 K at 5.22 GPa and drops to zero at about 30 GPa,displaying a dome-shaped temperature–pressure phase diagram.High-pressure x-ray diffraction measurement demonstrates that a crystalline-to-amorphous phase transition occurs at about 16 GPa in YbCd_(2)Sb_(2),revealing the robustness of pressure-induced superconductivity against structural instability.Similar structural phase transition may also occur in EuCd_(2)Sb_(2),causing the disappearance of magnetism.Our results show that XCd_(2)Sb_(2)(X=Eu and Yb)is a novel platform for exploring the interplay among magnetism,topology,and superconductivity. 展开更多
关键词 high pressure topological semimetal MAGNETISM SUPERCONDUCTIVITY
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Distribution laws of abutment pressure around fully mechanized top-coal caving face by in-situ measurement 被引量:2
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作者 CHANG Ju-cai 《Journal of Coal Science & Engineering(China)》 2011年第1期1-5,共5页
In order to obtain the distribution rules of abutment pressure around the 1151 (3) fully mechanized top-coal caving (FMTC) face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the ... In order to obtain the distribution rules of abutment pressure around the 1151 (3) fully mechanized top-coal caving (FMTC) face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the tailentry and headentry to measure the mining-induced stress. The distribution rules of the front and side abutment pressure were demonstrated. The results show that distribution rules of stress are obviously different in the vicinity of the face and entries. The peak value of abutment pressure in the protective coal pillar and face are located commonly in front of the working face along the strike, and they are located at the stress-decreased zone near the face. There is no stress peak value in the lateral coal mass beside the headentry in front of the face on the strike, and the peak value of abutment pressure appears at the rear area of the face. There are stress peak values both in the protective coal pillar and in the lateral coal mass beside the headentry to the dip. 展开更多
关键词 fully mechanized top-coal caving face abutment pressure in-situ measurement
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Local topography-induced pressure gradient effects on the wake and power output of a model wind turbine 被引量:1
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作者 Tengfei Cai Shyuan Cheng +1 位作者 Antonio Segalini Leonardo P.Chamorro 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第5期304-311,共8页
Wind-tunnel experiments were performed to study the effect of favorable and adverse constant pressure gradients(PG)from local changes in the topography right downwind of a model wind turbine.Particle image velocimetry... Wind-tunnel experiments were performed to study the effect of favorable and adverse constant pressure gradients(PG)from local changes in the topography right downwind of a model wind turbine.Particle image velocimetry was used to characterize the near and intermediate wake regions.We explored five scenarios,two favorable,two adverse PG,and a case with negligible PG.Results show that the PGs induce a wake deflection and modulate the wake.They imposed a relatively small impact on the turbulence kinetic energy and kinematic shear stress but a comparatively dominant effect on the bulk flow on the flow recovery.Based on this,a simple formulation is used to describe the impact of PG on the wake.We modeled the base flow through a linearized perturbation method;the wake is obtained by solving a simplified,integrated streamwise momentum equation.This approach reasonably estimated the flow profile and PG-induced power output variations. 展开更多
关键词 topographic effects pressure gradient Turbine wake Power output
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Topical negative pressure in managing severe peritonitis: A positive contribution? 被引量:1
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作者 Amin Ibrahim Amin Irshad A Shaikh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第27期3394-3397,共4页
AIM: To assess the use of topical negative pressure (TNP) in the management of severe peritonitis. METHODS: This is a four-year prospective analysis from January 2005 to December 2008 of 20 patients requiring TNP ... AIM: To assess the use of topical negative pressure (TNP) in the management of severe peritonitis. METHODS: This is a four-year prospective analysis from January 2005 to December 2008 of 20 patients requiring TNP following laparotomy for severe peritonitis. RESULTS: There were 11 males with an average age of (59.3 ± 3.95) years. Nine had a perforated viscus, five had anastomotic leaks, three had iatrogenic bowel injury, and a further three had severe pelvic inflammatory disease. TNP and the VAC Abdominal Dressing System were initially used. These were changed every two to three days. Abdominal closure was achieved in 15/20 patients within 4.53 ± 1.64 d. One patient required relaparotomy due to residual sepsis. Two patients with severe faecal peritonitis due to perforated diverticular disease received primary anastomosis at second look laparotomy, as sepsis and their general condition improved. In the remaining 5/20 cases, the abdomen was lee open due to bowel oedema and or abdominal wall oedema. Dressing was switched to TNP and VAC GranuFoam . Three of the five patients returned a few months later for abdominal wall reconstruction and restoration of intestinal continuity. Two patients developed intestinal fistulae. All 20 patients survived.CONCLUSION: The use of TNP is safe. Further studies are needed to assess its value in managing these difficult cases. 展开更多
关键词 Severe peritonitis Open abdomen topicalnegative pressure VAC Abdominal Dressing System VAC GranuFoam
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Pump-stopping pressure drop model considering transient leak-off of fracture network 被引量:1
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作者 WANG Fei XU Jiaxin +1 位作者 ZHOU Tong ZHANG Shicheng 《Petroleum Exploration and Development》 SCIE 2023年第2期473-483,共11页
By introducing the coupling flow expressions of main fracture-matrix, secondary fracture-matrix and main fracture-secondary fracture into the traditional main fracture material balance equation, the “main fracture-se... By introducing the coupling flow expressions of main fracture-matrix, secondary fracture-matrix and main fracture-secondary fracture into the traditional main fracture material balance equation, the “main fracture-secondary fracture-matrix” leak-off coupling flow model is established. The pressure-dependent fracture width equation and the wellbore injection volume equation are coupled to solve the pressure-rate continuity problem. The simulation and calculation of the bottomhole pressure drop and fracture network closure after the pump stopping in slickwater volumetric fracturing treatment are realized. The research results show that the log-log curve of pump-stopping bottomhole pressure drop derivative presents five characteristic slope segments, reflecting four dominant stages, i.e. inter-fracture crossflow, fracture network leak-off, fracture network closure and residual leak-off, after pump shutdown. At the initial time of pump shutdown for volumetric fracturing treatment of horizontal well, the crossflow between main and secondary fractures is obvious, and then the leak-off becomes dominant. The leak-off of main and secondary fractures shows a non-uniform decreasing trend. Specifically, the leak-off of main fractures is slow, while that of secondary fractures is fast;the fracture network as a whole presents the leak-off law of fast first, then slow, until close to zero. The influence of fracture network conductivity on the shape of pressure decline curve is relatively weaker than that of fracture network size. The fracture network conductivity is positively correlated with leak-off volume and fracture closure. The secondary fracture size is positively correlated with leakoff volume and closure of the secondary fracture, but negatively correlated with closure of the main fracture. Field data validation proves that the proposed model and simulation results can effectively reflect the closure characteristics of the fracture network, and the interpretation results are reliable and can reflect the non-uniform stimulation performance of each fracturing stage of an actual horizontal well. 展开更多
关键词 volume fracturing stop-pumping pressure drop fracture network characteristic curve transient leak-off frac-ture closure stimulation performance
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