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Going straight for the gut:gut-brain axis pathology and treatment of Parkinson's disease
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作者 Dominique Ebedes Cesar V.Borlongan 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2111-2112,共2页
This perspective focuses on the recent literature regarding the role of the gut-brain axis(GBA) in fecal microbiota transplantation(FMT) and stem cell therapy(SCT) in Parkinson's disease(PD).PD is the second most ... This perspective focuses on the recent literature regarding the role of the gut-brain axis(GBA) in fecal microbiota transplantation(FMT) and stem cell therapy(SCT) in Parkinson's disease(PD).PD is the second most common neurodegenerative disease in the United States,yet therapies remain limited.Current research suggests that the GBA may play a role in the pathogenesis of PD.GBAbased FMT as well as SCT offer promising new avenues for PD treatment.Pro bing the interactions between FMT and SCT with the GBA may reveal novel therapeutics for PD. 展开更多
关键词 straight PATHOLOGY PATHOGENESIS
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Industrial utilization of arsenic-containing gold dressing tailings as pellet prepared by straight grate process
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作者 LIU Wei GUO Zheng-qi +5 位作者 ZHU De-qing PAN Jian ZHANG Wu-ju WANG Jin ZHANG Ying-qun YIN Fu-xing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1888-1899,共12页
The utilization of arsenic-containing gold dressing tailings is an urgent issue faced by gold production companies worldwide.The thermodynamic analysis results indicate that ferrous arsenate(FeAsO_(4)),pyrite(FeS_(2))... The utilization of arsenic-containing gold dressing tailings is an urgent issue faced by gold production companies worldwide.The thermodynamic analysis results indicate that ferrous arsenate(FeAsO_(4)),pyrite(FeS_(2))and sodium cyanide(NaCN)in the arsenic-containing gold metallurgical tailings can be effectively removed using straight grate process,and the removal of pyrite and sodium cyanide is basically completed during the preheating stage,while the removal of ferrous arsenate requires the roasting stage.The pellets undergo a transformation from magnetite to hematite during the preheating process,and are solidified through micro-crystalline bonding and high-temperature recrystallization of hematite(Fe_(2)O_(3))during the roasting process.Ultimately,pellets with removal rates of 80.77% for arsenic,88.78% for sulfur,and 99.88% for cyanide are obtained,as well as the iron content is 61.1% and the compressive strength is 3071 N,meeting the requirements for blast furnace burden.This study provides an industrially feasible method for treating arsenic-containing gold smelting tailings,benefiting gold production enterprises. 展开更多
关键词 arsenic-containing gold dressing tailings pelletizing straight grate process recycling
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The world's longest straight road
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作者 徐成彬 《疯狂英语(新读写)》 2024年第9期50-51,77,共3页
Activity 1.Think about the following questions and write down your answers before reading the text.1.If you had the chance to travel on the longest straight road in the world,what would be the first thing you would do... Activity 1.Think about the following questions and write down your answers before reading the text.1.If you had the chance to travel on the longest straight road in the world,what would be the first thing you would do?2.Do you think having such a long straight road has more advantages or disadvan⁃tages?And why? 展开更多
关键词 TRAVEL And straight
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Related mechanisms and research progress in straight back syndrome 被引量:1
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作者 Mo-Wei Kong Zhen-Ying Pei +4 位作者 Xiong Zhang Qiu-Juan Du Qiang Tang Jun Li Guo-Xiang He 《World Journal of Cardiology》 2023年第10期479-486,共8页
Despite the high prevalence of straight back syndrome(SBS),there is still limited research on this condition,posing challenges for effective diagnosis and treatment.The disease has been known for a long time,but there... Despite the high prevalence of straight back syndrome(SBS),there is still limited research on this condition,posing challenges for effective diagnosis and treatment.The disease has been known for a long time,but there have been few related studies,which mostly consist of case reports.These studies have not been systematically summarized,making it difficult to meet the current needs of diagnosis and treatment.This article summarized the existing literature and comprehensively reviewed the diagnosis,pathogenesis,treatment,and research status of mitral valve prolapse related to SBS.We specifically emphasized the mechanisms and prognosis of SBS combined with mitral valve prolapse and discussed the latest research progress in this disease. 展开更多
关键词 straight back syndrome Mitral valve prolapse ARRHYTHMIA Review DIAGNOSIS Treatment
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Measuring tree stem diameters and straightness with depth-image computer vision
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作者 Hoang Tran Keith Woeste +2 位作者 Bowen Li Akshat Verma Guofan Shao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1395-1405,共11页
Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduc... Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduced time and labor costs.We developed the ForSense system to measure the diameters of trees at various points along the stem as well as stem straightness.Time use,mean absolute error(MAE),and root mean squared error(RMSE)metrics were used to compare the system against manual methods,and to compare the system against itself(reproducibility).Depth-derived diameter measurements of the stems at the heights of 0.3,1.4,and 2.7 m achieved RMSE of 1.7,1.5,and 2.7 cm,respectively.The ForSense system produced straightness measurement data that was highly correlated with straightness ratings by trained foresters.The ForSense system was also consistent,achieving sub-centimeter diameter difference with subsequent measures and less than 4%difference in straightness value between runs.This method of forest inventory,which is based on depth-image computer vision,is time efficient compared to manual methods and less computationally and technologically intensive compared to Structure-from-Motion(SFM)photogrammetry and ground-based LiDAR or terrestrial laser scanning(TLS). 展开更多
关键词 Forest inventory Depth sensing Computer vision Tree diameter Stem straightness Trunk volume
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Straight and twisted Weyl nodal line phonons in Ho2CF2 material
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作者 康鑫越 李金洋 李思 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期77-81,共5页
Based on first-principles calculations, symmetry analysis and model construction, we predict that Ho2CF2hosts both straight and twisted Weyl nodal lines in its bulk phonon spectrum. We identify that the top two phonon... Based on first-principles calculations, symmetry analysis and model construction, we predict that Ho2CF2hosts both straight and twisted Weyl nodal lines in its bulk phonon spectrum. We identify that the top two phonon bands entangle with each other, forming two straight Weyl nodal lines on the K–H and K′–H′paths at the Brillouin zone(BZ) boundary,and six twisted Weyl nodal lines within the BZ. All the Weyl nodal lines along the kz direction and across the entire BZ.The symmetry analysis indicates that these Weyl nodal lines are protected by the PT symmetry and crystal symmetry. The Berry phase and drumhead-like nontrivial surface states are calculated. We also construct a tight-binding model to describe these nodal lines. Our work provides an excellent material platform for exploring the fascinating physics associated with straight and twisted Weyl nodal line phonons. 展开更多
关键词 topological quasiparticles topological phonons straight nodal lines twisted nodal lines
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Development and Performance Evaluation of Catalyst for Productive Ethylene Cracking Feedstock in Selective Hydrocracking of Straight Run Diesel Oil
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作者 Tiezhen Zhang Xin Zhang +5 位作者 Yungang Jia Haiyan Li Fangming Xie Zijin Yan Hongyu Tian Hongyu Zhang 《Open Journal of Applied Sciences》 CAS 2023年第3期414-423,共10页
The upgrading of diesel oil to produce ethylene rich cracking feedstock is an important and promising technical route to reduce the ratio of diesel to gasoline. In the present work, a hydrocracking catalyst suitable f... The upgrading of diesel oil to produce ethylene rich cracking feedstock is an important and promising technical route to reduce the ratio of diesel to gasoline. In the present work, a hydrocracking catalyst suitable for selective hydrocracking of straight run diesel oil to produce high-quality ethylene cracking feedstock at low cost was developed, by optimizing the composition of catalyst support materials, using amorphous silicon aluminum and aluminum oxide with high mesopore content as the main support, and modified Y zeolite with excellent aromatic ring opening selectivity as the acidic component. The catalyst has in-depth characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, N<sub>2</sub>-low temperature adsorption-desorption, NH<sub>3</sub>-temperature-programmed desorption, and IR techniques. And its catalytic cracking straight run diesel oil performance was evaluated. The results show that the prepared catalyst has high polycyclic aromatic hydrocarbon ring opening cracking selectivity. However, alkanes retained in diesel distillates can achieve the goal of producing more ethylene cracking feedstocks with low BMCI value under low and moderate pressure conditions. This work may shed significant technical insight for oil refining transformation. 展开更多
关键词 straight Run Diesel Mild Hydrocracking CATALYST Ethylene Cracking Feedstock Process Research
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Crossing Limit Cycles of Planar Piecewise Hamiltonian Systems with Linear Centers Separated by Two Parallel Straight Lines
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作者 Zhou Jin 《Journal of Applied Mathematics and Physics》 2023年第5期1429-1447,共19页
In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of... In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of systems with a center in two zones and without equilibrium points in the other zone (or with a center in one zone and without equilibrium points in the other zones). In addition, we also give examples to illustrate that it can reach the maximal number. 展开更多
关键词 Limit Cycles Planar Piecewise Hamiltonian Systems straight Lines CENTERS Equilibrium Points
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Effect of Specific Verbal Instructions on the Identification of Pain Location during a Passive Straight Leg Raise Test
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作者 Masae Ikeya Takumi Jiroumaru +2 位作者 Hitomi Bunki Noriyuki Kida Teruo Nomura 《Open Journal of Therapy and Rehabilitation》 2023年第2期45-53,共9页
Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests... Musculoskeletal pain is common. Because pain is subjective, objectively describing it is crucial. However, pain assessment may cause distress in patients;therefore, physical therapists (PTs) should conduct these tests quickly and accurately. Simple and clear instructions are recommended for pain assessment. However, few studies have provided evidence to support this hypothesis. Correspondingly, this study aimed to confirm the effectiveness of specific verbal instructions for pain location during five consecutive Passive Straight Leg Raise (PSLR) tests. The 28 asymptomatic participants (age 27.4 ± 9.6 years) who provided informed consent received five consecutive PSLR tests: three without and two with specific verbal instructions to ascertain pain intensity, quality, and location. The participants drew pain locations on a body chart and described the pain intensity and quality after each test. All participants were interviewed regarding the differences they noted in the presence and absence of specific verbal instructions. Each pain location was classified into one of ten areas for statistical analysis. The proportion of participants who changed the pain location was compared between the tests using McNemar’s test, and the kappa coefficient was confirmed for consistency of pain location. There was a significant difference in the proportion of participants who changed their pain location between the second and third tests and from the third to the fourth test (McNemar’s test: p = 0.003). Kappa coefficients had low consistency (κ = 0.28) just after receiving the specific verbal instructions in the fourth test compared to the third test. Consistency improved in the fifth test (κ = 0.57);93% of the participants answered that the pain location had become clearer. This study revealed the effects of specific verbal instructions in identifying pain locations. This detailed information may help PTs provide appropriate treatment and contribute to reducing pain in clinical settings. 展开更多
关键词 Specific Verbal Instructions Pain Location Pain Assessment Passive straight Leg Raise Test
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采用STRAIGHT模型和深度信念网络的语音转换方法 被引量:4
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作者 王民 苏利博 +1 位作者 王稚慧 要趁红 《计算机工程与科学》 CSCD 北大核心 2016年第9期1950-1954,共5页
提出一种将STRAIGHT模型和深度信念网络DBN相结合实现语音转换的方式。首先,通过STRAIGHT模型提取出源说话人和目标说话人的语音频谱参数,用提取的频谱参数分别训练两个DBN得到语音高阶空间的个性特征信息;然后,用人工神经网络ANN将两... 提出一种将STRAIGHT模型和深度信念网络DBN相结合实现语音转换的方式。首先,通过STRAIGHT模型提取出源说话人和目标说话人的语音频谱参数,用提取的频谱参数分别训练两个DBN得到语音高阶空间的个性特征信息;然后,用人工神经网络ANN将两个具有高阶特征的空间连接并进行特征转换;最后,用基于目标说话人数据训练出的DBN来对转换后的特征信息进行逆处理得到语音频谱参数,并用STRAIGHT模型合成具有目标说话人个性化特征的语音。实验结果表明,采用此种方式获得的语音转换效果要比传统的采用GMM实现语音转换更好,转换后的语音音质和相似度与目标语音更接近。 展开更多
关键词 语音转换 straight模型 深度信念网络 高阶空间
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Multi-point flexible straightening process by reciprocating bending for metal profiles 被引量:2
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作者 Xue-ying HUANG Jun ZHAO +3 位作者 Gao-chao YU Qing-dang MENG Zhen-kai MU Yan-jun LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第7期2039-2050,共12页
A multi-point flexible straightening process characterized by reciprocating bending is proposed.Specifically,the process is analyzed in terms of deformation mechanism and verified by numerical simulations and physical... A multi-point flexible straightening process characterized by reciprocating bending is proposed.Specifically,the process is analyzed in terms of deformation mechanism and verified by numerical simulations and physical experiments of the straightening of a series of metal profiles with different materials and initial shapes.Further,the relationship between the bending radius and the times of reciprocating bending required to unify the curvature is discussed,and the distribution of residual stress after straightening is analyzed.The results show that the reciprocating bending process can eliminate the difference of the initial curvature,make the curvature of each section tend to be uniform;the times of reciprocating bending to reach the uniform curvature decreases with the decrease of bending radius.The straightness of the straightened profile obtained from the experiment and simulation is less than 0.2%,demonstrating a good feasibility of this method. 展开更多
关键词 multi-point flexibility metal profile reciprocating bending curvature unification over-bending straightening straightNESS
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基于STRAIGHT算法的汉语语音morphing方法
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作者 甘振业 杨鸿武 蔡莲红 《西北师范大学学报(自然科学版)》 CAS 2008年第5期34-37,42,共5页
提出了一种新的基于STRAIGHT算法的汉语语音morphing方法.通过标注源和目标STRAIGHT频谱上的特征点,并利用线性和对数叠加的方法实现对频谱的morphing;通过插值的方法对基频进行morphing.实验结果表明,morphing后的语音在语义特征不变... 提出了一种新的基于STRAIGHT算法的汉语语音morphing方法.通过标注源和目标STRAIGHT频谱上的特征点,并利用线性和对数叠加的方法实现对频谱的morphing;通过插值的方法对基频进行morphing.实验结果表明,morphing后的语音在语义特征不变的情况下,保持了源和目标语音的特征,morphing的结果获得了高质量的合成语音,MOS得分为3.87分. 展开更多
关键词 straight算法 汉语语音 MORPHING 语音修改 基频
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基于STRAIGHT算法的个性化语音生成方法 被引量:1
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作者 甘振业 杨鸿武 《甘肃科技》 2010年第4期34-35,86,共3页
介绍了一种基于STRAIGHT语音修改算法的个性化语音的方法。对输入的语音提取基本信息,并进行频谱分析;利用STRAIGHT算法对相关参数进行修改;通过STRAIGHT合成器生成新的个性化的语音。实验结果表明,该方法可以得到高质量的个性化合成语... 介绍了一种基于STRAIGHT语音修改算法的个性化语音的方法。对输入的语音提取基本信息,并进行频谱分析;利用STRAIGHT算法对相关参数进行修改;通过STRAIGHT合成器生成新的个性化的语音。实验结果表明,该方法可以得到高质量的个性化合成语音,MOS得分为4.18分。 展开更多
关键词 语音合成 straight算法 语音修改 个性化语音
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一种基于Straight的语音焦点合成方法 被引量:3
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作者 杨金辉 易中华 王煦法 《计算机工程》 CAS CSCD 北大核心 2005年第13期46-47,128,共3页
针对汉语焦点的特性,设计了接近自然语流风格的实验语料。通过对语料的分析,运用CART技术,建立了焦点的韵律模型。在语音合成阶段,使用韵律模型生成语音的韵律参数,结合Straight算法,实现了语音焦点的合成。对合成效果的评测表明,该方... 针对汉语焦点的特性,设计了接近自然语流风格的实验语料。通过对语料的分析,运用CART技术,建立了焦点的韵律模型。在语音合成阶段,使用韵律模型生成语音的韵律参数,结合Straight算法,实现了语音焦点的合成。对合成效果的评测表明,该方法能够合成自然度很高的语音焦点。 展开更多
关键词 焦点 分类回归树 straight 基频曲线 语音合成
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基于STRAIGHT模型和人工神经网络的语音转换 被引量:5
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作者 张正军 杨卫英 陈赞 《电声技术》 2010年第9期49-52,共4页
采用STRAIGHT语音分析-合成模型,提取源说话人和目标说话人的基频和光滑声道谱作为表征语音特征的参数。在频谱训练阶段,把声道谱转换成MFCC参数,采用人工神经网络算法对源-目标说话人的MFCC参数进行训练映射。主观和客观试验结果表明,... 采用STRAIGHT语音分析-合成模型,提取源说话人和目标说话人的基频和光滑声道谱作为表征语音特征的参数。在频谱训练阶段,把声道谱转换成MFCC参数,采用人工神经网络算法对源-目标说话人的MFCC参数进行训练映射。主观和客观试验结果表明,该方法能取得较好的转换效果,转换语音和目标语音较接近,易于理解。 展开更多
关键词 straight模型 人工神经网络:语音转换
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基于STRAIGHT模型和ANN的语音转换方法研究
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作者 王光艳 高丽萍 +1 位作者 黄奕婷 于宝雲 《新一代信息技术》 2020年第22期12-18,共7页
本文提出一种基于STRAIGHT模型的人工神经网络语音转换方法,该方法先利用STRAIGHT模型提取出语音的各特征参数后,再利用人工神经网络来进行模型特征参数的训练,经过不断的信号刺激,得到映射规则,最后再进行语音的特征参数的合成,完成整... 本文提出一种基于STRAIGHT模型的人工神经网络语音转换方法,该方法先利用STRAIGHT模型提取出语音的各特征参数后,再利用人工神经网络来进行模型特征参数的训练,经过不断的信号刺激,得到映射规则,最后再进行语音的特征参数的合成,完成整个语音转换系统。STRAIGHT模型能提高转换语音的自然度、清晰度和可懂度。采用ANN进行模型特征参数训练,可以自动迭代更新数据权重,得到的映射规则能更好地规范要转换的特征参数,使得语音转换质量更高。 展开更多
关键词 语音转换 straight模型 人工神经网络
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Monte Carlo Method for the Uncertainty Evaluation of Spatial Straightness Error Based on New Generation Geometrical Product Specification 被引量:10
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作者 WEN Xiulan XU Youxiong +2 位作者 LI Hongsheng WANG Fenglin SHENG Danghong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期875-881,共7页
Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the resul... Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the results should be given together when the measurement result is given. Nowadays most researches on straightness focus on error calculation and only several research projects evaluate the measurement uncertainty based on "The Guide to the Expression of Uncertainty in Measurement(GUM)". In order to compute spatial straightness error(SSE) accurately and rapidly and overcome the limitations of GUM, a quasi particle swarm optimization(QPSO) is proposed to solve the minimum zone SSE and Monte Carlo Method(MCM) is developed to estimate the measurement uncertainty. The mathematical model of minimum zone SSE is formulated. In QPSO quasi-random sequences are applied to the generation of the initial position and velocity of particles and their velocities are modified by the constriction factor approach. The flow of measurement uncertainty evaluation based on MCM is proposed, where the heart is repeatedly sampling from the probability density function(PDF) for every input quantity and evaluating the model in each case. The minimum zone SSE of a shaft measured on a Coordinate Measuring Machine(CMM) is calculated by QPSO and the measurement uncertainty is evaluated by MCM on the basis of analyzing the uncertainty contributors. The results show that the uncertainty directly influences the product judgment result. Therefore it is scientific and reasonable to consider the influence of the uncertainty in judging whether the parts are accepted or rejected, especially for those located in the uncertainty zone. The proposed method is especially suitable when the PDF of the measurand cannot adequately be approximated by a Gaussian distribution or a scaled and shifted t-distribution and the measurement model is non-linear. 展开更多
关键词 uncertainty evaluation Monte Carlo method spatial straightness error quasi particle swarm optimization minimum zone solution geometrical product specification
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Occurrence of Rice Dry Straight Head Disease and Its Control
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作者 黄自安 刘小林 +2 位作者 倪春耕 胡宏云 王振荣 《Plant Diseases and Pests》 CAS 2010年第2期1-4,9,共5页
[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the ... [Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the reason of dry straight head disease in Chuzhou area, some common control measures were summarized. [Result] The characteristic of main symptoms included incidence of single plant, incidence of cluster, inclusive incidence between clusters. Sporadic normal rice grains existed in diseased spikes under the incidence of grains. The main pathogenic factors of dry straight head disease were concentration of arsenic or lack of elements, belonging to physiological disease, while the effect of other pathogenic factors could not be excluded. Heavy application of organic fertilizer and crop rotation should be conducted, white soil field should be paid more attention about the changes of disease condition with more wet and dry roasting over fields. Application time of micro fertilizer should be chosen properly, while tillering final stage and pollen formation stage must be adjusted to avoid high temperature, irrigation management should also be improved. [Conclusion] The study could provide reference for preventing rice dry straight head disease. 展开更多
关键词 Rice dry straight head disease Research SYMPTOM Cause of disease Arsenic concentration Prevention and control measure
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Finite element analysis of contact fatigue and bending fatigue of a theoretical assembling straight bevel gear pair 被引量:15
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作者 邓松 华林 +1 位作者 韩星会 黄松 《Journal of Central South University》 SCIE EI CAS 2013年第2期279-292,共14页
The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulat... The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulative fatigue criterion and the stress-life equation, the key meshing states of the gear pair were investigated for the contact fatigue and the bending fatigue. Then, the reliability of the proposed model was proved by comparing the calculation result with the simulation result. Further study was performed to analyze the variation of the contact fatigue stress and the bending fatigue stress under different loads. Furthermore, the roles of the driving pinion and the driven gear pair were evaluated in the fatigue life of the straight bevel gear pair and the main fatigue failure mode was determined for the significant gear. The results show that the fatigue failure of the driving pinion is the main fatigue failure for the straight bevel gear pair and the bending fatigue failure is the main fatigue failure for the driving pinion. 展开更多
关键词 straight bevel gear finite element method contact fatigue bending fatigue
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Numerical investigation on the flow and power of small-sized multi-bladed straight Darrieus wind turbine 被引量:10
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作者 JIANG Zhi-chao DOI Yasuaki ZHANG Shu-you 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1414-1421,共8页
Straight Darrieus wind turbine has attractive characteristics such as the ability to accept wind from random direction and easy installation and maintenance. But its aerodynamic performance is very complicated,especia... Straight Darrieus wind turbine has attractive characteristics such as the ability to accept wind from random direction and easy installation and maintenance. But its aerodynamic performance is very complicated,especially for the existence of dynamic stall. How to get better aerodynamic performance arouses lots of interests in the design procedure of a straight Darrieus wind turbine. In this paper,mainly the effects of number of blades and tip speed ratio are discussed. Based on the numerical investigation,an assumed asymmetric straight Darrieus wind turbine is proposed to improve the averaged power coefficient. As to the numerical method,the flow around the turbine is simulated by solving the 2D unsteady Navier-Stokes equation combined with continuous equation. The time marching method on a body-fitted coordinate system based on MAC (Marker-and-Cell) method is used. O-type grid is generated for the whole calculation domain. The characteristics of tangential and normal force are discussed related with dynamic stall of the blade. Averaged power coefficient per period of rotating is calculated to evaluate the eligibility of the turbine. 展开更多
关键词 Small-sized straight Darrieus wind turbine Multi-bladed Power coefficient
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