期刊文献+
共找到68,918篇文章
< 1 2 250 >
每页显示 20 50 100
Evaluation of a handheld creatinine measurement device for real-time determination of serum creatinine in radiology departments
1
作者 Stefan Haneder Alexandra Gutfleisch +5 位作者 Claudia Meier Joachim Brade Dieter Hannak Stefan O Schoenberg Christoph R Becker Henrik J Michaely 《World Journal of Radiology》 CAS 2012年第7期328-334,共7页
AIM: To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination. METHODS: In this institutional review board-approved, ... AIM: To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination. METHODS: In this institutional review board-approved, prospective study, 401 patients referred for contrastenhanced computed tomography were included at two centres. Capillary (c)SCr was determined using two devices A+B and venous (v)SCr was determined in the centre's laboratory. Method comparison statistics for both centres and for vSCr<>1.2 mg/dL, receiver operating characteristic analysis, negative predictive values (NPV), sensitivity and specificity were calculated pre-/ post-curve offset correction with vSCr. RESULTS: Pearson's coefficients for cSCr vs vSCr were: centre 1-A:0.93/B:0.92; centre 2-A:0.85/B:0.82 (all P < 0.0001). Overall correlation was better for vSCr > 1.2 mg/dL. The area under the receiver operating characteristic curves showed a high accuracy for cSCr, but the device underestimated SCr, which was confirmed by Bland-Altman plot. Addition of the offset correction factor to the original data from centre 1 resulted in an improvement in sensitivity for detecting patients at risk (> 1.2 mg/dL), whilst maintaining acceptable specificity and improving NPV. CONCLUSION: This study showed the feasibility of SCr determination using the evaluated handheld device in a routine clinical setting. The device showed high sensitivity and high NPV, but may significantly underestimate SCr without offset correction to local laboratories. 展开更多
关键词 Contrast-medium-induced NEPHROPATHY Nephrogenic SYSTEMIC FIBROSIS Point of care testing Serum CREATININE determination StatSensor
下载PDF
基于Real-time PCR法检测乳粉中牛源性成分定量研究
2
作者 陈晨 史国华 +5 位作者 陈勃旭 张瑞 王玉欣 贾文珅 陈佳 周巍 《粮油食品科技》 CAS CSCD 北大核心 2024年第2期159-164,共6页
基于Real-timePCR建立了乳粉中牛源性成分相对定量检测方法,并对牛的特异性引物与探针进行了特异性、灵敏度和稳定性测试。通过模拟不同浓度牛乳粉与马乳粉混合样本,根据其△Ct值的函数关系进行线性拟合进而绘制标准曲线,建立乳粉中牛... 基于Real-timePCR建立了乳粉中牛源性成分相对定量检测方法,并对牛的特异性引物与探针进行了特异性、灵敏度和稳定性测试。通过模拟不同浓度牛乳粉与马乳粉混合样本,根据其△Ct值的函数关系进行线性拟合进而绘制标准曲线,建立乳粉中牛源性成分的相对定量检测。结果显示,该方法的最低检测限为0.00001 mg/mL,回收率为91.11%~119.2%,组间变异系数≤0.58%、组内变异系数≤1.44%。说明该方法在特异性与稳定性上适用于乳粉中牛源性成分及含量的掺假检测。 展开更多
关键词 牛乳粉 马乳粉 real-time PCR 掺假检测
下载PDF
一种基于real-time PCR技术的TTV检测方法的建立及应用
3
作者 贾毅博 王高玉 +4 位作者 邓宛心 林彩云 杨华 陈运春 尹飞飞 《海南医学院学报》 CAS 北大核心 2024年第7期489-497,共9页
目的:本研究旨在开发一种具有更高灵敏度和特异性的TTV检测技术,为揭示TTV在多种疾病过程中的作用提供重要的技术支持。方法:为了更精确、灵敏的检测TTV,本研究分析了目前公布的所有亚型的TTV基因序列,在此基础上建立了一种基于UTR区域... 目的:本研究旨在开发一种具有更高灵敏度和特异性的TTV检测技术,为揭示TTV在多种疾病过程中的作用提供重要的技术支持。方法:为了更精确、灵敏的检测TTV,本研究分析了目前公布的所有亚型的TTV基因序列,在此基础上建立了一种基于UTR区域的real-time PCR检测方法,并与文献报道应用较为广泛的PCR检测方法进行了对比。结果:本研究建立的方法在1×10^(7)~1×10^(1) copies/μL标准品浓度范围内具有良好的线性关系,相关系数为1.000,斜率为-3.446,检测下限为1×10^(1) copies/μL。重复性试验结果显示,组内变异系数为7.22%,表明本方法重复性、稳定性较强。针对30份临床样本,使用本研究建立的real-time PCR检测方法及目前被多个研究所使用的4套引物进行对比。结果表明,本研究所建立的方法灵敏度显著高于文献中报道的4种方法(P<0.01);Sanger测序结果表明,本方法检测出的30份阳性样本均为TTV,检测特异性为100%。结论:本研究采用基于TaqMan探针的real-time PCR检测方法,检测灵敏性高、覆盖基因型范围广,尤其对于TTV病毒载量较低的情况下能够进行定量检测,对于TTV病毒的致病性及作为免疫标志物的应用提供重要的技术支持。 展开更多
关键词 Torque teno virus 基因组扩增测序 real-time PCR检测
下载PDF
Sex Determination in Homo sapiens as a Multi-Step Process: Potential for Development of Variants and Sex Differences in Disease Risk
4
作者 David A. Hart 《Journal of Biomedical Science and Engineering》 2024年第1期13-34,共22页
Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific ... Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific approach has been a successful strategy for survival of a large variety of species including humans, the fidelity of sex determination leading to 100% cis-binary outcomes is not achieved in many species, with evidence for homosexual or bisexual behaviour evident in more than 1500 species. Thus, such outcomes indicates that sex determination is a multi-step process and not a single event, and as such, could lead to the appearance of variants during the process which developed much earlier than humans. Variants could arise either due to intrinsic variation in the steps of determination, or also be influenced by environmental factors of a biological or psychological nature. In contrast to homosexual variants which do not require interventions such as hormone therapy or surgery, expression of gender dysphoria, is more based in psychology, but also has biological underpinnings and can be influenced by such hormonal interventions and surgery. While the numbers of those with gender dysphoria is small (~0.6% - 1.0% of population), the attention given to this issue raises the possibility of biological and psychological environmental factors impacting the emergence of some of those expressing gender dysphoria. Furthermore, transitioning from male-to-female or female-to-male can have consequences regarding disease risks latter in life, including the appearance of autoimmune diseases. This review will attempt to review some of the evidence regarding sex determination, discuss why the system has potentially not been improved upon during evolution, how a potential role for sex chromosome function on neurodevelopment may be central to variation in humans, and how commitment to the current strategy is likely integrated into other sex-related events such as puberty, pregnancy, and menopause to ensure species survival. It will also discuss how variants in sex determination could contribute to sex differences in disease risk and how epigenetic modifications could play a role in such risk. . 展开更多
关键词 Sex determination Variant Development Fidelity of Sex determination Biological Sex determination Species Variation
下载PDF
Real-time data processing method for CO_(2) dispersion interferometer on EAST
5
作者 张家敏 姚远 +6 位作者 刘郁阳 储宇奇 阮天翼 张耀 刘海庆 揭银先 凌必利 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期121-126,共6页
A real-time data processing system is designed for the carbon dioxide dispersion interferometer(CO_(2)-DI)on EAST.The system utilizes the parallel and pipelining capabilities of an fieldprogrammable gate array(FPGA)to... A real-time data processing system is designed for the carbon dioxide dispersion interferometer(CO_(2)-DI)on EAST.The system utilizes the parallel and pipelining capabilities of an fieldprogrammable gate array(FPGA)to digitize and process the intensity of signals from the detector.Finally,the real-time electron density signals are exported through a digital-to-analog converter(DAC)module in the form of analog signals.The system has been successfully applied in the CO_(2)-DI system to provide low-latency electron density input to the plasma control system on EAST.Experimental results of the latest campaign with long-pulse discharges on EAST(2022–2023)demonstrate that the system can respond effectively in the case of rapid density changes,proving its reliability and accuracy for future electron density calculation. 展开更多
关键词 dispersion interferometer real-time electron density FPGA EAST
下载PDF
Real-Time Intelligent Diagnosis of Co-frequency Vibration Faults in Rotating Machinery Based on Lightweight-Convolutional Neural Networks
6
作者 Xin Pan Xiancheng Zhang +1 位作者 Zhinong Jiang Guangfu Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期264-282,共19页
The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the... The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the equipment.In engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively time-consuming.Therefore,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault diagnosis.The critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation method.Based on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is realized.Moreover,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault diagnosis.It is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance. 展开更多
关键词 Co-frequency vibration real-time diagnosis LW-CNN Data augmentation
下载PDF
Integrated strategy for real-time wind power fluctuation mitigation and energy storage system control
7
作者 Yu Zhang Yongkang Zhang Tiezhou Wu 《Global Energy Interconnection》 EI CSCD 2024年第1期71-81,共11页
To address the impact of wind-power fluctuations on the stability of power systems,we propose a comprehensive approach that integrates multiple strategies and methods to enhance the efficiency and reliability of a sys... To address the impact of wind-power fluctuations on the stability of power systems,we propose a comprehensive approach that integrates multiple strategies and methods to enhance the efficiency and reliability of a system.First,we employ a strategy that restricts long-and short-term power output deviations to smoothen wind power fluctuations in real time.Second,we adopt the sliding window instantaneous complete ensemble empirical mode decomposition with adaptive noise(SW-ICEEMDAN)strategy to achieve real-time decomposition of the energy storage power,facilitating internal power distribution within the hybrid energy storage system.Finally,we introduce a rule-based multi-fuzzy control strategy for the secondary adjustment of the initial power allocation commands for different energy storage components.Through simulation validation,we demonstrate that the proposed comprehensive control strategy can smoothen wind power fluctuations in real time and decompose energy storage power.Compared with traditional empirical mode decomposition(EMD),ensemble empirical mode decomposition(EEMD),and complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)decomposition strategies,the configuration of the energy storage system under the SW-ICEEMDAN control strategy is more optimal.Additionally,the state-of-charge of energy storage components fluctuates within a reasonable range,enhancing the stability of the power system and ensuring the secure operation of the energy storage system. 展开更多
关键词 SW-ICEEMDAN HESS real-time smoothing Rule-based multi-fuzzy control SoC
下载PDF
Nanomaterial-assisted wearable glucose biosensors for noninvasive real-time monitoring:Pioneering point-of-care and beyond
8
作者 Moein Safarkhani Abdullah Aldhaher +5 位作者 Golnaz Heidari Ehsan Nazarzadeh Zare Majid Ebrahimi Warkiani Omid Akhavan YunSuk Huh Navid Rabiee 《Nano Materials Science》 EI CAS CSCD 2024年第3期263-283,共21页
This review explores glucose monitoring and management strategies,emphasizing the need for reliable and userfriendly wearable sensors that are the next generation of sensors for continuous glucose detection.In additio... This review explores glucose monitoring and management strategies,emphasizing the need for reliable and userfriendly wearable sensors that are the next generation of sensors for continuous glucose detection.In addition,examines key strategies for designing glucose sensors that are multi-functional,reliable,and cost-effective in a variety of contexts.The unique features of effective diabetes management technology are highlighted,with a focus on using nano/biosensor devices that can quickly and accurately detect glucose levels in the blood,improving patient treatment and control of potential diabetes-related infections.The potential of next-generation wearable and touch-sensitive nano biomedical sensor engineering designs for providing full control in assessing implantable,continuous glucose monitoring is also explored.The challenges of standardizing drug or insulin delivery doses,low-cost,real-time detection of increased blood sugar levels in diabetics,and early digital health awareness controls for the adverse effects of injectable medication are identified as unmet needs.Also,the market for biosensors is expected to expand significantly due to the rising need for portable diagnostic equipment and an ever-increasing diabetic population.The paper concludes by emphasizing the need for further research and development of glucose biosensors to meet the stringent requirements for sensitivity and specificity imposed by clinical diagnostics while being cost-effective,stable,and durable. 展开更多
关键词 Glucose sensor BIOSENSOR Wearable devices NONINVASIVE real-time monitoring
下载PDF
Real-Time Detection and Instance Segmentation of Strawberry in Unstructured Environment
9
作者 Chengjun Wang Fan Ding +4 位作者 Yiwen Wang Renyuan Wu Xingyu Yao Chengjie Jiang Liuyi Ling 《Computers, Materials & Continua》 SCIE EI 2024年第1期1481-1501,共21页
The real-time detection and instance segmentation of strawberries constitute fundamental components in the development of strawberry harvesting robots.Real-time identification of strawberries in an unstructured envi-r... The real-time detection and instance segmentation of strawberries constitute fundamental components in the development of strawberry harvesting robots.Real-time identification of strawberries in an unstructured envi-ronment is a challenging task.Current instance segmentation algorithms for strawberries suffer from issues such as poor real-time performance and low accuracy.To this end,the present study proposes an Efficient YOLACT(E-YOLACT)algorithm for strawberry detection and segmentation based on the YOLACT framework.The key enhancements of the E-YOLACT encompass the development of a lightweight attention mechanism,pyramid squeeze shuffle attention(PSSA),for efficient feature extraction.Additionally,an attention-guided context-feature pyramid network(AC-FPN)is employed instead of FPN to optimize the architecture’s performance.Furthermore,a feature-enhanced model(FEM)is introduced to enhance the prediction head’s capabilities,while efficient fast non-maximum suppression(EF-NMS)is devised to improve non-maximum suppression.The experimental results demonstrate that the E-YOLACT achieves a Box-mAP and Mask-mAP of 77.9 and 76.6,respectively,on the custom dataset.Moreover,it exhibits an impressive category accuracy of 93.5%.Notably,the E-YOLACT also demonstrates a remarkable real-time detection capability with a speed of 34.8 FPS.The method proposed in this article presents an efficient approach for the vision system of a strawberry-picking robot. 展开更多
关键词 YOLACT real-time detection instance segmentation attention mechanism STRAWBERRY
下载PDF
Models to Simulate Effective Coverage of Fire Station Based on Real-Time Travel Times
10
作者 Sicheng Zhu Dingli Liu +2 位作者 Weijun Liu Ying Li Tian Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期483-513,共31页
In recent years,frequent fire disasters have led to enormous damage in China.Effective firefighting rescues can minimize the losses caused by fires.During the rescue processes,the travel time of fire trucks can be sev... In recent years,frequent fire disasters have led to enormous damage in China.Effective firefighting rescues can minimize the losses caused by fires.During the rescue processes,the travel time of fire trucks can be severely affected by traffic conditions,changing the effective coverage of fire stations.However,it is still challenging to determine the effective coverage of fire stations considering dynamic traffic conditions.This paper addresses this issue by combining the traveling time calculationmodelwith the effective coverage simulationmodel.In addition,it proposes a new index of total effective coverage area(TECA)based on the time-weighted average of the effective coverage area(ECA)to evaluate the urban fire services.It also selects China as the case study to validate the feasibility of the models,a fire station(FS-JX)in Changsha.FS-JX station and its surrounding 9,117 fire risk points are selected as the fire service supply and demand points,respectively.A total of 196 simulation scenarios throughout a consecutiveweek are analyzed.Eventually,1,933,815 sets of valid sample data are obtained.The results showed that the TECA of FS-JX is 3.27 km^(2),which is far below the standard requirement of 7.00 km^(2) due to the traffic conditions.The visualization results showed that three rivers around FS-JX interrupt the continuity of its effective coverage.The proposed method can provide data support to optimize the locations of fire stations by accurately and dynamically determining the effective coverage of fire stations. 展开更多
关键词 Fire services fire station effective coverage real-time traffic SIMULATION
下载PDF
FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors
11
作者 Hui‑Yin Shen Jing‑Long Zhang +1 位作者 Jie Zhang Jian‑Hang Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期101-113,共13页
Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a sel... Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,China.The experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 ms.At count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV. 展开更多
关键词 Neutron-gamma discrimination Liquid scintillation detector real-time spectrum analyzer
下载PDF
Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales
12
作者 Qin Ma Zizhen Fan +5 位作者 Ping Wang Siya Ma Jian Wen Fengqin Cao Xianwu Lin Rihui Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期938-947,共10页
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi... transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control. 展开更多
关键词 Zeugodacus cucurbitae TRANSFORMER transformer-2 sex determination RNA interference biological control
下载PDF
Relative orbit determination algorithm of space targets with passive observation
13
作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
下载PDF
Real-Time Object Detection and Face Recognition Application for the Visually Impaired
14
作者 Karshiev Sanjar Soyoun Bang +1 位作者 SookheeRyue Heechul Jung 《Computers, Materials & Continua》 SCIE EI 2024年第6期3569-3583,共15页
The advancement of navigation systems for the visually impaired has significantly enhanced their mobility by mitigating the risk of encountering obstacles and guiding them along safe,navigable routes.Traditional appro... The advancement of navigation systems for the visually impaired has significantly enhanced their mobility by mitigating the risk of encountering obstacles and guiding them along safe,navigable routes.Traditional approaches primarily focus on broad applications such as wayfinding,obstacle detection,and fall prevention.However,there is a notable discrepancy in applying these technologies to more specific scenarios,like identifying distinct food crop types or recognizing faces.This study proposes a real-time application designed for visually impaired individuals,aiming to bridge this research-application gap.It introduces a system capable of detecting 20 different food crop types and recognizing faces with impressive accuracies of 83.27%and 95.64%,respectively.These results represent a significant contribution to the field of assistive technologies,providing visually impaired users with detailed and relevant information about their surroundings,thereby enhancing their mobility and ensuring their safety.Additionally,it addresses the vital aspects of social engagements,acknowledging the challenges faced by visually impaired individuals in recognizing acquaintances without auditory or tactile signals,and highlights recent developments in prototype systems aimed at assisting with face recognition tasks.This comprehensive approach not only promises enhanced navigational aids but also aims to enrich the social well-being and safety of visually impaired communities. 展开更多
关键词 Artificial intelligence deep learning real-time object detection application
下载PDF
Real-Time Tunable Gas Sensing Platform Based on SnO2 Nanoparticles Activated by Blue Micro-Light-Emitting Diodes
15
作者 Gi Baek Nam Jung-El Ryu +25 位作者 Tae Hoon Eom Seung Ju Kim Jun Min Suh Seungmin Lee Sungkyun Choi Cheon Woo Moon Seon Ju Park Soo Min Lee Byungsoo Kim Sung Hyuk Park Jin Wook Yang Sangjin Min Sohyeon Park Sung Hwan Cho Hyuk Jin Kim Sang Eon Jun Tae Hyung Lee Yeong Jae Kim Jae Young Kim Young Joon Hong Jong-In Shim Hyung-Gi Byun Yongjo Park Inkyu Park Sang-Wan Ryu Ho Won Jang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期103-119,共17页
Micro-light-emitting diodes(μLEDs)have gained significant interest as an activation source for gas sensors owing to their advantages,including room temperature operation and low power consumption.However,despite thes... Micro-light-emitting diodes(μLEDs)have gained significant interest as an activation source for gas sensors owing to their advantages,including room temperature operation and low power consumption.However,despite these benefits,challenges still exist such as a limited range of detectable gases and slow response.In this study,we present a blueμLED-integrated light-activated gas sensor array based on SnO_(2)nanoparticles(NPs)that exhibit excellent sensitivity,tunable selectivity,and rapid detection with micro-watt level power consumption.The optimal power forμLED is observed at the highest gas response,supported by finite-difference time-domain simulation.Additionally,we first report the visible light-activated selective detection of reducing gases using noble metal-decorated SnO_(2)NPs.The noble metals induce catalytic interaction with reducing gases,clearly distinguishing NH3,H2,and C2H5OH.Real-time gas monitoring based on a fully hardwareimplemented light-activated sensing array was demonstrated,opening up new avenues for advancements in light-activated electronic nose technologies. 展开更多
关键词 Micro-LED Gas sensor array Low power consumption Metal decoration real-time detection
下载PDF
A deep reinforcement learning approach to gasoline blending real-time optimization under uncertainty
16
作者 Zhiwei Zhu Minglei Yang +3 位作者 Wangli He Renchu He Yunmeng Zhao Feng Qian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期183-192,共10页
The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of production.However,the effectiveness of real-time optimization i... The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of production.However,the effectiveness of real-time optimization in gasoline blending relies on accurate blending models and is challenged by stochastic disturbances.Thus,we propose a real-time optimization algorithm based on the soft actor-critic(SAC)deep reinforcement learning strategy to optimize gasoline blending without relying on a single blending model and to be robust against disturbances.Our approach constructs the environment using nonlinear blending models and feedstocks with disturbances.The algorithm incorporates the Lagrange multiplier and path constraints in reward design to manage sparse product constraints.Carefully abstracted states facilitate algorithm convergence,and the normalized action vector in each optimization period allows the agent to generalize to some extent across different target production scenarios.Through these well-designed components,the algorithm based on the SAC outperforms real-time optimization methods based on either nonlinear or linear programming.It even demonstrates comparable performance with the time-horizon based real-time optimization method,which requires knowledge of uncertainty models,confirming its capability to handle uncertainty without accurate models.Our simulation illustrates a promising approach to free real-time optimization of the gasoline blending process from uncertainty models that are difficult to acquire in practice. 展开更多
关键词 Deep reinforcement learning Gasoline blending real-time optimization PETROLEUM Computer simulation Neural networks
下载PDF
Phase behavior of gas condensate in porous media using real-time computed tomography scanning
17
作者 Wen-Long Jing Lei Zhang +5 位作者 Ai-Fen Li Jun-Jie Zhong Hai Sun Yong-Fei Yang Yu-Long Cheng Jun Yao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1032-1043,共12页
The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir formations.Sandstone was used as a samp... The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir formations.Sandstone was used as a sample to investigate the influence of porous media on the phase behavior of the gas condensate.The pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network model.The sandstone core sample was then saturated with gas condensate for the pressure depletion experiment.After each pressure-depletion state was stable,realtime CT scanning was performed on the sample.The scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous media.Pore network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas condensate.Four types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and elaborately.The results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT cells.The average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below Pmax.The volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet ganglia.This study provides crucial experimental evidence for the phase behavior changing process of gas condensate in porous media during the depletion production of gas condensate reservoirs. 展开更多
关键词 Gas condensate Pressure depletion real-time micro-computed tomography scanning Distribution of condensate liquid
下载PDF
The Impact of Sleep Determination on Procrastination before Bedtime:The Role of Anxiety
18
作者 Na Liu Junxiu Wang Wanli Zang 《International Journal of Mental Health Promotion》 2024年第5期377-387,共11页
Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of ... Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of the internet and electronic devices have significantly impacted people’s sleep patterns,particularly through bedtime procrastination.Therefore,this study aims to investigate the relationship and underlying mechanisms between sleep determination,anxiety,and bedtime procrastination among the Chinese population.Method:The study utilized data from a national survey—the China Residents’Sleep Condition Survey(November 2021,with 6,037 participants).By constructing mediation and moderation models,it analyzed the relationship and mechanisms between sleep determination and bedtime procrastination,highlighting the dual role of anxiety:as a mediator between sleep determination and bedtime procrastination,and as a moderator of their relationship.Results:There was a negative correlation between sleep determination and bedtime procrastination;anxiety was related to an increase in bedtime procrastination behaviors;In the interplay between sleep determination and pre-bedtime procrastination,the regulatory effect of anxiety is found to be more pronounced than its intermediary role,with anxiety significantly diminishing the inverse relationship between sleep determination and procrastination before bedtime.Conclusion:Bedtime procrastination can lead to sleep issues,thus reducing sleep quality.Enhancing sleep determination or alleviating pre-sleep anxiety can help inhibit bedtime procrastination behaviors.Intervening and reducing bedtime procrastination is one of the effective measures to improve sleep quality. 展开更多
关键词 Sleep determination bedtime procrastination ANXIETY MEDIATION moderation
下载PDF
Research Progress on Purification Process, Content Determination and Pharmacological Action of Atractylodin
19
作者 Xin SUN Jingwen WANG +1 位作者 Yang XI Chenghao JIN 《Asian Agricultural Research》 2024年第3期33-35,40,共4页
Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rh... Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rheumatic arthralgia.Atractylodin is the main active component extracted and isolated from Atractylodis Rhizoma.A large number of studies have found that atractylodin has excellent drug activity in improving gastrointestinal emptying,anti-inflammation,inhibiting malignant tumor and reducing blood lipid.In this paper,the purification process and pharmacological activity of Atractylodin were summarized to provide a theoretical basis for basic research,clinical application and further development and utilization of atractylodin. 展开更多
关键词 ATRACTYLODIN PHARMACOLOGICAL action PURIFICATION PROCESS CONTENT determination
下载PDF
A Real-time Lithological Identification Method based on SMOTE-Tomek and ICSA Optimization
20
作者 DENG Song PAN Haoyu +5 位作者 LI Chaowei YAN Xiaopeng WANG Jiangshuai SHI Lin PEI Chunyu CAI Meng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期518-530,共13页
In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on ... In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on machine learning and mud logging data is studied in this paper.This method can effectively utilize downhole parameters collected in real-time during drilling,to identify lithology in real-time and provide a reference for optimization of drilling parameters.Given the imbalance of lithology samples,the synthetic minority over-sampling technique(SMOTE)and Tomek link were used to balance the sample number of five lithologies.Meanwhile,this paper introduces Tent map,random opposition-based learning and dynamic perceived probability to the original crow search algorithm(CSA),and establishes an improved crow search algorithm(ICSA).In this paper,ICSA is used to optimize the hyperparameter combination of random forest(RF),extremely random trees(ET),extreme gradient boosting(XGB),and light gradient boosting machine(LGBM)models.In addition,this study combines the recognition advantages of the four models.The accuracy of lithology identification by the weighted average probability model reaches 0.877.The study of this paper realizes high-precision real-time lithology identification method,which can provide lithology reference for the drilling process. 展开更多
关键词 mud logging data real-time lithological identification improved crow search algorithm petroleum geological exploration SMOTE-Tomek
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部