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Optimizing Stock Market Prediction Using Long Short-Term Memory Networks
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作者 Nadia Afrin Ritu Samsun Nahar Khandakar +1 位作者 Md. Masum Bhuiyan Md. Imdadul Islam 《Journal of Computer and Communications》 2025年第2期207-222,共16页
Deep learning plays a vital role in real-life applications, for example object identification, human face recognition, speech recognition, biometrics identification, and short and long-term forecasting of data. The ma... Deep learning plays a vital role in real-life applications, for example object identification, human face recognition, speech recognition, biometrics identification, and short and long-term forecasting of data. The main objective of our work is to predict the market performance of the Dhaka Stock Exchange (DSE) on day closing price using different Deep Learning techniques. In this study, we have used the LSTM (Long Short-Term Memory) network to forecast the data of DSE for the convenience of shareholders. We have enforced LSTM networks to train data as well as forecast the future time series that has differentiated with test data. We have computed the Root Mean Square Error (RMSE) value to scrutinize the error between the forecasted value and test data that diminished the error by updating the LSTM networks. As a consequence of the renovation of the network, the LSTM network provides tremendous performance which outperformed the existing works to predict stock market prices. 展开更多
关键词 Long short-Term Memory (LSTM) Stock Market PREDICTION Time Series Analysis Deep Learning
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Short-Term and Long-Term Outcomes among COVID-19 Survivors: A Multi-Center Prospective Observational Study
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作者 Mohsin Ahmed Abdul Wadud Chowdhury +13 位作者 Md. Arifur Rahman A. K. M. Monwarul Islam Matiur Rahman Helal Uddin Ahmed Md. Shariful Islam Nahid Hasan Salahuddin Anis Shiblee Md. Habibur Rahman Mostafa Kamal Md. Nur-A-Alam Khan Aminul Islam Syed Tariq Reza A. K. M. Nasir Uddin Murtaza Khair 《International Journal of Clinical Medicine》 CAS 2024年第11期486-501,共16页
Background: Since the outbreak of the COVID-19 pandemic caused massive case fatalities across the world, people have been left with significant physical and mental disabilities, which has had an adverse impact on thei... Background: Since the outbreak of the COVID-19 pandemic caused massive case fatalities across the world, people have been left with significant physical and mental disabilities, which has had an adverse impact on their quality of life. The objective of this study is to measure the short-term and long-term outcomes among COVID-19 survivors. Methods: This is a six-month-long multicentre prospective observational study, carried out in four specialized hospitals in the capital city Dhaka, where six hundred participants were enrolled by non-probability convenience sampling. Data were collected through three structured interviews, and follow-ups were done during discharge, at 1st month, and 6th month. An analytical study was done on demographic variables, socio-economic conditions, physical findings and outcomes. Data were analysed using Statistical Package for Social Sciences (SPSS). Results: A total of 600 participants were enrolled. The mean age was 49.83. Many participants belong to the age range of 31 to 40 years. More than two-thirds (72.7%) of participants were male, whereas 27.30% were female. Most patients admitted had mild and moderate COVID-19 symptoms (40% and 58%, respectively). Among short-term COVID complications, it was found that 43.3% of the participants complained of fatigue, 32.6% of depression, 24.7% of sleep disturbance, 19% of anxiety and, 5% memory loss. In long-term COVID complications the number reduced significantly: 5% of the participants complained of fatigue, 10% of depression, 2.7% of sleep disturbance, 7.3% of anxiety and, 2.7% memory loss. The severity of lung parenchymal disease also reduced in long term COVID symptoms. The study found a statistically significant relationship between age groups and CT severity index (χ2 = 9.458, p = 0.032). Most patients (29.2%) in the under-30 age group had a CT Severity Index score of 2 & 3 (29.2%). The important CT Severity Index scores for individuals aged 30 to 60 years were 3 and 4, accounting for 37.7% and 33.3%, respectively. In the over-60 age group, 40.8% of patients showed a CT Severity Index score of 4, showing a range of 51% - 75%. Conclusion: This study found that fatigue, depression, and sleep disturbances are prevalent among COVID-19 survivors;however, these symptoms generally reduce over time. Lung problems improved;however, some patients suffered from persistent effects. Older patients, especially those with pre-existing conditions, suffer from more severe outcomes. These findings underscore the need for ongoing care for COVID-19 survivors. 展开更多
关键词 COVID-19 Survivors short-Term and Long-Term Outcomes Lung Complications COVID-19 Outcomes Long-Term Complications
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Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh
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作者 Muhit Abdullah Md. Abir Tazim Chowdhury +9 位作者 Satyajit Sharma Rehana Akther Munama Magdum Munjerin Refat Synthee Md. Zafar-Al-Nimari Saikat Das Gupta Saleh Ahmed Samir Kumar Biswas M. Quamrul Islam Talukder Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第9期145-156,共12页
Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-... Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk. 展开更多
关键词 Off-Pump Coronary Artery Bypass Grafting Left Ventricular Dysfunction (LVD) short-Term Outcomes
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Wind Power Forecasting Using Grey Wolf Optimized Long Short-Term Memory Based on Numerical Weather Prediction
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作者 Mohamed El-Dosuky Reema Alowaydan Bashayer Alqarni 《Journal of Power and Energy Engineering》 2024年第12期1-16,共16页
Wind power generation is among the most promising and eco-friendly energy sources today. Wind Power Forecasting (WPF) is essential for boosting energy efficiency and maintaining the operational stability of power grid... Wind power generation is among the most promising and eco-friendly energy sources today. Wind Power Forecasting (WPF) is essential for boosting energy efficiency and maintaining the operational stability of power grids. However, predicting wind power comes with significant challenges, such as weather uncertainties, wind variability, complex terrain, limited data, insufficient measurement infrastructure, intricate interdependencies, and short lead times. These factors make it difficult to accurately forecast wind behavior and respond to sudden power output changes. This study aims to precisely forecast electricity generation from wind turbines, minimize grid operation uncertainties, and enhance grid reliability. It leverages historical wind farm data and Numerical Weather Prediction data, using k-Nearest Neighbors for pre-processing, K-means clustering for categorization, and Long Short-Term Memory (LSTM) networks for training and testing, with model performance evaluated across multiple metrics. The Grey Wolf Optimized (GWO) LSTM classification technique, a deep learning model suited to time series analysis, effectively handles temporal dependencies in input data through memory cells and gradient-based optimization. Inspired by grey wolves’ hunting strategies, GWO is a population-based metaheuristic optimization algorithm known for its strong performance across diverse optimization tasks. The proposed Grey Wolf Optimized Deep Learning model achieves an R-squared value of 0.97279, demonstrating that it explains 97.28% of the variance in wind power data. This model surpasses a reference study that achieved an R-squared value of 0.92 with a hybrid deep learning approach but did not account for outliers or anomalous data. 展开更多
关键词 Wind Power Forecasting Long short-Term Memory Numerical Weather Prediction Grey Wolf Optimization
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Comparative study on the performance of ConvLSTM and ConvGRU in classification problems-taking early warning of short-duration heavy rainfall as an example 被引量:1
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作者 Meng Zhou Jingya Wu +1 位作者 Mingxuan Chen Lei Han 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期52-57,共6页
卷积长短期记忆单元ConvLSTM和卷积门控循环单元ConvGRU是两种广泛应用的深度学习单元,通过将循环机制与卷积运算相结合,常常用于时空序列的预测.为了明确上述两种模型的收敛速度和分类能力,需要使用相同的模型架构对相同的分类问题进... 卷积长短期记忆单元ConvLSTM和卷积门控循环单元ConvGRU是两种广泛应用的深度学习单元,通过将循环机制与卷积运算相结合,常常用于时空序列的预测.为了明确上述两种模型的收敛速度和分类能力,需要使用相同的模型架构对相同的分类问题进行预测.本研究将北京短时强降水区级预警问题看作深度学习中的二分类问题,使用京津冀雷达网的组合反射率数据和北京区域内的自动气象站降雨数据进行深度学习模型的训练和评估.结果表明,ConvGRU的收敛速度比ConvLSTM快约25%.ConvLSTM和ConvGRU的预警性能随地区,时间,降雨强度的变化趋势相似,但大部分ConvLSTM的得分较高,少数情况下ConvGRU的得分较高. 展开更多
关键词 深度学习 卷积长短期记忆单元 卷积门控循环单元 分类问题
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拟南芥根的辐射形态相关基因SHORT-ROOT研究进展 被引量:9
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作者 高潜 刘玉瑛 +2 位作者 费一楠 李大朋 刘祥林 《植物学通报》 CSCD 北大核心 2008年第3期363-372,共10页
从模式植物拟南芥中克隆得到的SHORT-ROOT基因(SHR)被证明参与根部形态建成途径。目前已知SHR是与根辐射形态直接相关的重要调控因子,同时也参与维持根尖分生组织的活性。SHR既作为转录因子启动下游基因的表达,又作为短程信号调节根的... 从模式植物拟南芥中克隆得到的SHORT-ROOT基因(SHR)被证明参与根部形态建成途径。目前已知SHR是与根辐射形态直接相关的重要调控因子,同时也参与维持根尖分生组织的活性。SHR既作为转录因子启动下游基因的表达,又作为短程信号调节根的发育。本文综述了SHR相关研究进展,并展望其研究前景。 展开更多
关键词 辐射形态 short-ROOT 信号网络 转录因子
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Short-course在畜产品加工学课程教学实践中的探索与应用 被引量:3
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作者 敖晓琳 李美良 +1 位作者 李诚 杨勇 《高等农业教育》 2018年第3期75-77,共3页
畜产品加工学课程对学生的综合知识和实践能力要求较高,实践课程的改革与进一步完善有助于学生对知识的掌握和能力的提高。将Short-course的教学方式引入该课程的实践教学,结合四川农业大学的实际情况,从short-coures的方案制定、实施... 畜产品加工学课程对学生的综合知识和实践能力要求较高,实践课程的改革与进一步完善有助于学生对知识的掌握和能力的提高。将Short-course的教学方式引入该课程的实践教学,结合四川农业大学的实际情况,从short-coures的方案制定、实施、学习效果评价等方面进行实践教学的探索,以丰富畜产品加工学课程实践教学的内容,增加实践教学方式,培养适应社会的综合性人才。 展开更多
关键词 short-course 畜产品加工学 教学实践
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拟南芥SHORT-ROOT基因稀有密码子分析及其在原核细胞中的表达和纯化
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作者 孙验玲 郑玲 +5 位作者 穆春华 于倩倩 何春梅 耿骁渝 郑红霞 刘霞 《生物技术通讯》 CAS 2016年第1期90-95,共6页
目的:在大肠杆菌中重组表达拟南芥SHORT-ROOT(SHR)蛋白并纯化。方法:将SHR基因编码区克隆至p GEX-4T-2表达载体,构建重组质粒p GEX-4T-2-SHR并转化大肠杆菌Rosetta(DE3),表达产物经谷胱甘肽亲和层析凝胶4B分离纯化,SDS-PAGE分析和Wester... 目的:在大肠杆菌中重组表达拟南芥SHORT-ROOT(SHR)蛋白并纯化。方法:将SHR基因编码区克隆至p GEX-4T-2表达载体,构建重组质粒p GEX-4T-2-SHR并转化大肠杆菌Rosetta(DE3),表达产物经谷胱甘肽亲和层析凝胶4B分离纯化,SDS-PAGE分析和Western印迹鉴定。结果:SHR融合蛋白在大肠杆菌Rosetta(DE3)中获得表达,亲和纯化后,SDS-PAGE显示相对分子质量为预期的86×103,且经Western印迹确证。结论:获得了拟南芥SHR融合蛋白,为进一步研究其生物学功能奠定了基础。 展开更多
关键词 拟南芥 short-ROOT蛋白 稀有密码子 原核表达 纯化
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一种基于long short-term memory的唇语识别方法 被引量:4
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作者 马宁 田国栋 周曦 《中国科学院大学学报(中英文)》 CSCD 北大核心 2018年第1期109-117,共9页
唇动视觉信息是说话内容的重要载体。受嘴唇外观、背景信息和说话习惯等影响,即使说话者说相同的内容,唇动视觉信息也会相差很大。为解决唇语视觉信息多样性的问题,提出一种基于long short-term memory(LSTM)的新的唇语识别方法。以往... 唇动视觉信息是说话内容的重要载体。受嘴唇外观、背景信息和说话习惯等影响,即使说话者说相同的内容,唇动视觉信息也会相差很大。为解决唇语视觉信息多样性的问题,提出一种基于long short-term memory(LSTM)的新的唇语识别方法。以往大多数的方法从嘴唇外表信息入手。本方法用嘴唇关键点坐标描述嘴唇形变信息作为唇语视频的特征,它具有类内一致性和类间区分性的特点。然后利用LSTM对特征进行时序编码,它能学习具有区分性和泛化性的空间-时序特征。在公开的唇语数据集GRID、MIRACL-VC和Oulu VS上对本方法做了针对分割的单词或短语的说话者独立的唇语识别评估。在GRID和MIRACL-VC上,本方法的准确率比传统方法至少高30%;在Oulu VS上,本方法的准确率接近于最优结果。以上实验结果表明,本文提出的基于LSTM的唇语识别方法有效地解决了唇语视觉信息多样性的问题。 展开更多
关键词 唇语识别 LONG short-TERM MEMORY 计算机视觉
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时空高效的允许插入空位的short-read比对 被引量:1
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作者 杨永洁 钟诚 《小型微型计算机系统》 CSCD 北大核心 2019年第5期1004-1009,共6页
short-read alignment(短序列比对)在下一代测序技术中得到广泛运用.精确识别测序序列中的gap(空位)是后续基因组解读的基础,而现有的允许空位的short-read比对算法效果并不理想或者不允许插入空位.对于查询序列和参考序列均为short re... short-read alignment(短序列比对)在下一代测序技术中得到广泛运用.精确识别测序序列中的gap(空位)是后续基因组解读的基础,而现有的允许空位的short-read比对算法效果并不理想或者不允许插入空位.对于查询序列和参考序列均为short reads的比对问题,通过采取训练查询序列样本数据寻找不同物种和不同read长度匹配的最优插入空位数量的策略,对大规模的short reads进行两两比对,以减少算法的迭代次数,从而减少算法所需的中间矩阵计算量,并用向量存储算法比对过程中的中间矩阵元素值,以降低存储空间需求,提出一种改进的short-read比对算法.数千万的short reads对准实验结果表明:与已有的有代表性的同类算法相比,本文算法在确保short-read比对精确度的前提下,降低了所需的运行时间和存储空间. 展开更多
关键词 short-read比对 双序列比对 动态规划 gap识别
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Short-and long-term behaviors of drifts in the Callovo-Oxfordian claystone at the Meuse/Haute-Marne Underground Research Laboratory 被引量:5
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作者 G.Armand A.Noiret +1 位作者 J.Zghondi D.M.Seyedi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第3期221-230,共10页
Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obt... Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical (HM) behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional (mode I) and shear fractures (modes II and III) induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts. 展开更多
关键词 Field experiments Claystone Tunnel convergence Induced fractures short- and long-term behaviors
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Motor Fault Diagnosis Based on Short-time Fourier Transform and Convolutional Neural Network 被引量:45
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作者 Li-Hua Wang Xiao-Ping Zhao +2 位作者 Jia-Xin Wu Yang-Yang Xie Yong-Hong Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1357-1368,共12页
With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and ... With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and poor accuracy, when handling big data. In this study, the research object was the asynchronous motor in the drivetrain diagnostics simulator system. The vibration signals of different fault motors were collected. The raw signal was pretreated using short time Fourier transform (STFT) to obtain the corresponding time-frequency map. Then, the feature of the time-frequency map was adap- tively extracted by using a convolutional neural network (CNN). The effects of the pretreatment method, and the hyper parameters of network diagnostic accuracy, were investigated experimentally. The experimental results showed that the influence of the preprocessing method is small, and that the batch-size is the main factor affecting accuracy and training efficiency. By investigating feature visualization, it was shown that, in the case of big data, the extracted CNN features can represent complex mapping relationships between signal and health status, and can also overcome the prior knowledge and engineering experience requirement for feature extraction, which is used by tra- ditional diagnosis methods. This paper proposes a new method, based on STFT and CNN, which can complete motor fault diagnosis tasks more intelligently and accurately. 展开更多
关键词 Big data Deep learning short-time Fouriertransform Convolutional neural network MOTOR
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Stool characteristics of infants receiving short-chain galactooligosaccharides and long-chain fructo-oligosaccharides:A review 被引量:7
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作者 Petra AMJ Scholtens Dominique AM Goossens Annamaria Staiano 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13446-13452,共7页
Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics ... Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics such as stool consistency and stool frequency. Such effects on stool characteristics can be beneficial for young infants as hard stools and even constipation is common in that age group. Prebiotics in infant milk formulas have been introduced to exert similar functionalities. A specific mixture of prebiotics consists of a combination of short chain galacto-oligosaccharides and long-chain fructo-oligosaccharides(scGOS/lcFOS) in a ratio of 9:1. This specific mixture has been developed to closely resemble the molecular size composition of HMO. Many studies have been done with scGOS/lcFOS, and indicators for digestive comfort have often been included as secondary outcomes. This review summarizes the effects of scGOS/lcFOS(9:1) on stool consistency,stool frequency and transit time in healthy term and preterm infants. In several of the studies with scGOS/lcFOS in a ratio of 9:1 in infant milk formulas, positive effects of this mixture on stool characteristics such as stool consistency and stool frequency were observed. As stool consistency was shown to be correlated to whole gut transit time, scGOS/lcFOS can be hypothesised to have a role in reducing the risk of constipation. 展开更多
关键词 short-chain galactooligosaccharides Long-chain fructooligosaccharides Stool consistency Stool frequency INFANTS
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An autotrophic nitrogen removal process:Short-cut nitrification combined with ANAMMOX for treating diluted effluent from an UASB reactor fed by landfill leachate 被引量:26
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作者 Jie Liu Jian'e Zuo +3 位作者 Tang Yang Shuquan Zhu Sulin Kuang Kaijun Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期777-783,共7页
A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted effluent from an upflow ... A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted effluent from an upflow anaerobic sludge bed (UASB) reactor treating high ammonium municipal landfill leachate.The SN process was performed in an aerated upflow sludge bed (AUSB) reactor (working volume 3.05 L),treating about 50% of the diluted raw wastewater.The ammonium removal efficiency and the ratio of NO 2 N to NOx-N in the effluent were both higher than 80%,at a maximum nitrogen loading rate of 1.47 kg/(m 3 ·day).The ANAMMOX process was performed in an UASB reactor (working volume 8.5 L),using the mix of SN reactor effluent and diluted raw wastewater at a ratio of 1:1.The ammonium and nitrite removal efficiency reached over 93% and 95%,respectively,after 70-day continuous operation,at a maximum total nitrogen loading rate of 0.91 kg/(m 3 ·day),suggesting a successful operation of the combined process.The average nitrogen loading rate of the combined system was 0.56 kg/(m 3 ·day),with an average total inorganic nitrogen removal efficiency 87%.The nitrogen in the effluent was mostly nitrate.The results provided important evidence for the possibility of applying SN-ANAMMOX after UASB reactor to treat municipal landfill leachate. 展开更多
关键词 landfill leachate short-cut nitrification anaerobic ammonia oxidation autotrophic nitrogen removal
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Short-Impending Earthquake Anomaly Index Extraction of GNSS Continuous Observation Data in Yunnan,Southwestern China 被引量:14
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作者 Min Hong Desheng Shao +4 位作者 Tengfei Wu Shuangxi Zhang Yong Zhang Lingli Wang Xiaodong Qian 《Journal of Earth Science》 SCIE CAS CSCD 2018年第1期230-236,共7页
This paper presents a comprehensive area expansion prediction index method to apply GNSS for short-impending prediction of earthquakes. Based on continuous GNSS observation data from Yunnan Province, a displacement fi... This paper presents a comprehensive area expansion prediction index method to apply GNSS for short-impending prediction of earthquakes. Based on continuous GNSS observation data from Yunnan Province, a displacement field was detected after data cycle-slip repair using precision data processing software and geophysical field effect model correction. The Yunnan area was divided into 56 grid cells for displacement field interpolation to obtain a more uniform displacement field and a strain field variation time series. The pre-earthquake response of each grid-cell expansion time series was evaluated and synthesized to extract a short-impending earthquake anomaly identification index. The results show that this index indicated occurrence times and hypocenter for earthquakes of magnitude M≥5. Fourteen earthquakes were predicted accurately, and there were five false reports. This index can therefore be used for the short-impending prediction of earthquakes. 展开更多
关键词 GNSS short-impending earthquake prediction strain anomaly index southwestern China.
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The effect of fire disturbance on short-term soil respiration in typical forest of Greater Xing'an Range, China 被引量:11
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作者 Long Sun Tongxin Hu +4 位作者 Ji Hong Kim Futao Guo Hong Song Xinshuang Lv Haiqing Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期613-620,共8页
We investigated the effect of fire disturbance on short-term soil respiration in birch (Betula platyphylla Suk.) and larch (Larix gmelinii Rupr.) forests in Greater Xing’an range, northeastern China for further u... We investigated the effect of fire disturbance on short-term soil respiration in birch (Betula platyphylla Suk.) and larch (Larix gmelinii Rupr.) forests in Greater Xing’an range, northeastern China for further understanding of its effect on the carbon cycle in ecosystems. Our study show that post-fire soil respiration rates in B. platyphylla and L. gmelinii forests were reduced by 14%and 10%, respectively. In contrast, the soil heterotrophic respiration rates in the two types of forest were similar in post-fire and control plots. After fire, the contribution of root respiration to total soil respiration was dramatically reduced. Variation in soil respiration rates was explained by soil moisture (W) and soil tem-perature (T) at a depth of 5 cm. Exponential regression fitted T and W models explained Rs rates in B. platyphylla control and post-fire plots (83.1% and 86.2%) and L. gmelinii control and post-fire plots (83.7%and 88.7%). In addition, the short-term temperature coefficients in B. 展开更多
关键词 fire disturbance short-term soil respiration environmentfactors Q10
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Improvement of type 2 diabetes mellitus after gastric cancer surgery:Short-term outcome analysis after gastrectomy 被引量:14
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作者 Ji Yeong An Yoo Min Kim +2 位作者 Min Ah Yun Byeong Hee Jeon Sung Hoon Noh 《World Journal of Gastroenterology》 SCIE CAS 2013年第48期9410-9417,共8页
AIM:To evaluate the effect of gastrectomy on diabetes control in patients with type 2 diabetes mellitus and early gastric cancer.METHODS:Data from 64 patients with early gastric cancer and type 2 diabetes mellitus wer... AIM:To evaluate the effect of gastrectomy on diabetes control in patients with type 2 diabetes mellitus and early gastric cancer.METHODS:Data from 64 patients with early gastric cancer and type 2 diabetes mellitus were prospectively collected.All patients underwent curative gastrectomy(36 subtotal gastrectomy with gastroduodenostomy,16subtotal gastrectomy with gastrojejunostomy,12 total gastrectomy)and their physical and laboratory data were evaluated before and 3,6 and 12 mo after surgery.RESULTS:Fasting blood glucose(FBS),HbA1c,insulin,C-peptide,and homeostasis model assessment-estimated insulin resistance were significantly improved 3mo after surgery,regardless of operation type,and the significant improvement in all measured values,except HbA1c,was sustained up to 12 mo postoperatively.Approximately 3.1%of patients stopped diabetes medication and had HbA1c<6.0%and FBS<126 mg/dL.54.7%of patients decreased their medication,and had reduced FBS or HbA1c.In multivariate analysis,good diabetic control was not associated with operation type,but was associated with diabetes duration.CONCLUSION:Diabetes improved in more than 50%of patients during the first year after gastric cancer surgery.The degree of diabetes control was related to diabetes duration. 展开更多
关键词 Type 2 diabetes MELLITUS GASTRECTOMY GASTRIC cancer short-TERM outcome GLUCOSE control
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Validation of a HRGC–ECNI/LRMS method to monitor short-chain chlorinated paraffins in human plasma 被引量:8
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作者 Jiazhi Xu Weijing Guo +5 位作者 Linhuan Wei Yuan Gao Haijun Zhang Yichi Zhang Ming Sun Jiping Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第1期289-295,共7页
Short-chain chlorinated paraffins(SCCPs) are produced in high volume and have the high potential to pose a threat to human health. However, little information is available for SCCP contamination in human blood/plasma/... Short-chain chlorinated paraffins(SCCPs) are produced in high volume and have the high potential to pose a threat to human health. However, little information is available for SCCP contamination in human blood/plasma/serum, mainly due to the difficulty of sample preparation and quantitative analysis. A method using high resolution gas chromatography coupled with electron capture negative ionization low resolution mass spectrometry(HRGC–ECNI/LRMS) was developed and validated to measure SCCPs in human plasma. The pretreatment process included protein denaturation and lipid elimination, liquid–liquid extraction with a mixture of n-hexane/dichloromethane(1:1, V/V), and cleanup on a multilayer silica column. The blank controls, including procedural blank, vacuum blood collection tube blank, and instrumental blank, were the most pivotal points for the reliable analysis of SCCPs. The average value of procedural blanks was 9.0 ng/g; and the method detection limit(MDL), calculated as the sum of the average procedural blank value and 3 times of the standard deviation of the procedural blanks, was 12.6 ng/g plasma. The validated method was applied to measure the concentrations of the total SCCPs(∑ SCCPs) in50 plasma samples from a general population. The measured plasma concentrations of ∑SCCPs ranged from <MDL to 203 ng/g wet weight(ww), with an average value of 32.0 ng/g ww.The relative abundance profiles of SCCPs in plasma samples were dominated by C10- and C11-CP congener groups centered on Cl6–7. The developed method can be used for the comprehensive and large-scale investigation of SCCP levels in human plasma. 展开更多
关键词 short-chain chlorinated PARAFFINS SAMPLE preparation QUANTITATIVE analysis Human PLASMA
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A preliminary study of the effects of plastic film-mulched raised beds on soil temperature and crop performance of early-sown short-season spring maize(Zea mays L.) in the North China Plain 被引量:11
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作者 Jing Dang Weili Liang +2 位作者 Guiyan Wang Pengfei Shi Dan Wu 《The Crop Journal》 SCIE CAS CSCD 2016年第4期331-337,共7页
To identify a strategy for earlier sowing and harvesting of spring maize(Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of Ch... To identify a strategy for earlier sowing and harvesting of spring maize(Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of China Agricultural University in 2014 and 2015. A short-season cultivar, Demeiya number 1(KX7349), was used in the experiment. Soil temperature to 5 cm depth in the early crop growth stage, crop growth, crop yield, and water use of different treatments(plastic film-mulched raised bed(RF) and flat field without plastic film mulching(CK) in 2014; RF, plastic film-mulched flat field(FF), and CK in 2015)were measured or calculated and compared. Soil temperature in the film-mulched treatments was consistently higher than that in CK(1.6–3.5 °C in average) during the early growth stage. Crops in plastic film-mulched treatments used 214 fewer growing-degree days(GDDs) in 2014 and 262 fewer GDDs in 2015. In 2014, the RF treatment yielded 32.7%higher biomass than CK, although its 9.4% higher grain yield was not statistically significant. Also, RF used 17.9% less water and showed 33.1% higher water use efficiency(WUE) than CK. In 2015, RF and FF showed 56.2% and 49.5% higher yield, 15.0% and 4.5%lower water use(ET), and 63.4% and 75.7% higher WUE, respectively, than CK. RF markedly increased soil temperature in the early crop season, accelerated crop growth, reduced ET,and greatly increased crop yield and WUE. Compared with FF, RF had no obvious effect on crop growth rate, although soil temperature during the period between sowing and stem elongation was slightly increased. However, RF resulted in lower ET and higher WUE than FF. Effects of RF on soil water dynamics as well as its cost-effectiveness remain topics for further study. 展开更多
关键词 Raised BED Film MULCH Spring short-season Maize North China PLAIN
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Kinetic analysis of waste activated sludge hydrolysis and short-chain fatty acids production at pH 10 被引量:13
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作者 FENG Leiyu, YAN Yuanyuan, CHEN Yinguang State key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期589-594,共6页
The accumulation of short-chain fatty acids (SCFAs), a preferred carbon source for enhanced biological phosphorus removal microbes, was significantly improved when waste activated sludge (WAS) was fermented at pH ... The accumulation of short-chain fatty acids (SCFAs), a preferred carbon source for enhanced biological phosphorus removal microbes, was significantly improved when waste activated sludge (WAS) was fermented at pH 10. The kinetics of WAS hydrolysis and SCFAs production at pH 10 was investigated. It was observed that during WAS anaerobic fermentation the accumulation of SCFAs was limited by the hydrolysis process, and both the hydrolysis of WAS particulate COD and the accumulation of SCFAs followed first-order kinetics. The hydrolysis and SCFAs accumulation rate constants increased with increasing temperature from 10 to 35℃, which could be described by the Arrhenius equation. The kinetic data further indicated that SCFAs production at pH 10 was a biological process. Compared with the experiment of pH uncontrolled (blank test), both the rate constants of WAS hydrolysis and SCFAs accumulation at 20℃ were improved significantly when WAS was fermented at pH 10. 展开更多
关键词 waste activated sludge HYDROLYSIS short-chain fatty acids KINETICS alkaline pH
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