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温度补偿振荡器用SC切谐振器

宇航计测技术 1984年第S1期 16-22页

作者： John R.Vig raymond l Filler 高景浩

本文介绍对SC切TCXO谐振器的频温一切角特性的测定情况。θ值是在下转折点温度范围+100℃至-70℃的数值。根据这种谐振器的频率温度(f-T)特性,测出了在不同温度范围(即-40℃—+75℃, -54℃—+85℃和0℃—+60℃)的最佳切角、最小频率偏... 详细信息

本文介绍对SC切TCXO谐振器的频温一切角特性的测定情况。θ值是在下转折点温度范围+100℃至-70℃的数值。根据这种谐振器的频率温度(f-T)特性,测出了在不同温度范围(即-40℃—+75℃, -54℃—+85℃和0℃—+60℃)的最佳切角、最小频率偏移和最大频率-温度斜率。业已发现,用普通切割设备就能很容易达到切角公差。初步的滞后测量结果表明,SC切谐振器可以使TCXO的稳定度得到明显提高。

关键词：谐振器温度范围切角热滞共振器振荡器电子设备转折点温度 SC

Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment: a voxelbased lesion symptom mapping study

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Neural Regeneration Research 2014年第7期9卷 766-772页

作者： Alexandria M.Reynolds Denise M.Peters Jennifer M.C.Vendemia lenwood P.Smith raymond C.Sweet Gordon C.Baylis Debra Krotish Stacy l.Fritz Department of Psychology Barnwell College University of South Carolina Department of Exercise Science University of South Carolina Department of Psychology University of South Carolina Neurosurgery Center University of South Carolina School of Medicine Western Kentucky University University of South Carolina School of Medicine

Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro- nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deficits expected after damage to the cortical motor system due to stroke. These findings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex.

关键词： nerve regeneration magnetic resonance imaging stroke cerebral cortex motor cortex voxel-based lesion symptom mapping motor function prognosis neural regeneration

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促进交通运输中的实验文化

城市交通 2022年第3期20卷 1-4页

作者： Joseph l.Schofer raymond Chan() 马瑞李健(译) 西北大学工程与应用科学学院埃文斯顿IL 60208 同济大学交通运输工程学院上海201804

交通系统随时可能发生各种变化。通过实验的方法研究这些变化有利于掌握其因果规律,并验证哪些行为有效、哪些行为无效。对实验室实验、分析模型、现场试验和自然实验四类实验进行介绍,提出通过从自然中学习、将事件变成实验、共享数据... 详细信息

交通系统随时可能发生各种变化。通过实验的方法研究这些变化有利于掌握其因果规律,并验证哪些行为有效、哪些行为无效。对实验室实验、分析模型、现场试验和自然实验四类实验进行介绍,提出通过从自然中学习、将事件变成实验、共享数据等促进交通运输研究中的实验文化。通过建立一种实验文化,既能进行现场实验,又可以利用自然实验的机会进行学习,进而对交通系统的脆弱性、项目和政策的适用性了解更多。

关键词：交通运输实验文化实验室实验分析模型现场试验自然实验

Sizing of a Filter (<i>l-C</i>) for a 180°Control Inverter Connected to a Medium Voltage Network

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Open Journal of Applied Sciences 2021年第5期11卷 565-576页

作者： Kouakou Fernand Koffi Gondo Yake raymond Gbegbe Georges loum Olivier Asseu Institut National Polytechnique Félix Houphouë t Boigny (INP-HB) Yamoussoukro C&#244 te d’Ivoire Université Félix Houphouë t Boigny (UFHB) Abidjan C&#244 te d’Ivoire Ecole Supérieure Africaine des Technologies d’Information et de la Communication (ESATIC) Abidjan C&#244 te d’Ivoire

This paper studies the design and sizing of a filter (l-C) for an inverter with 180° control in Medium voltage (MV), based on formulas of the capacitance of the capacitor C and the inductance l of the filter (l-C) of an SPWM inverter. These formulas were obtained by minimizing two parameters: the reactive power of the capacitor (capped at 5% of the apparent power of the load) and the ripple of the current flowing through inductance l (capped at 10% of the current supplying the load). The application of these formulas for the calculation of the filter (l-C) of the 180° control inverter in MV is not conclusive. Studies have been carried out to make them applicable. The results show that limiting the current ripple in the inductor to 10% of the load current is a valid assumption and that limiting the reactive power of the capacitor to 5% of the apparent power of the load presents shortcomings. The results also show that setting the inductance l of the filter to lmaxi and the capacitor C from 35 × Cmaxi to 400 × Cmaxi gives voltage and current THDs that meet the 519 IEEE-2014 standards.

关键词： filter (l-C) THD inverter with 180° control and with SPWM control mathematical iterations MV. MATlAB-SIMUlINK

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怎样减小振动对SC切石英晶体振荡器的影响

宇航计测技术 1983年第S1期 63-68页

作者： VINCENT R.ROSATI raymond l.FIllER 杨易旻

要给现代化通讯、导航及雷达系统提供必要的频谱纯度,就必须减小石英谐振器的加速灵敏度（γ）,例如从γ=10-10/g 减小到γ=10-12/g。为了实现这一目的,当前正在研究几种（仅与谐振器有关的）无源法。专门设计的单谐振器和双谐振器是无... 详细信息

要给现代化通讯、导航及雷达系统提供必要的频谱纯度,就必须减小石英谐振器的加速灵敏度（γ）,例如从γ=10-10/g 减小到γ=10-12/g。为了实现这一目的,当前正在研究几种（仅与谐振器有关的）无源法。专门设计的单谐振器和双谐振器是无源法应用的两个实例。应用电子线路的有源法已经进行了研究,它能进一步使振动影响减到1/50。然而,用来实现这种方法的变容二极管的非线性限制了可能达到的最终减小量。本文介绍一种可供使用的有源法。这种方法的原理是应用 SC 切晶体的线性电压～频率特性,而要点在于把相位适当的振动模拟信号电压直接加在晶体电极上。用几块不同的SC 切晶体所做的一系列试验都确认了这种有源法的效果。把晶体振荡器略加修改,是为了加入补偿电压,而不会改变振荡器的电路原理。补偿测试范围:加速度1至14g,振动频率50至500Hz;补偿电压大小取决于γ的初值,可从-20至+20V（峰-峰值）。初步实验结果表明,在不连续的频率上γ值几乎能降低三个数量级,在50到500Hz 连续频率范围能降低一个数量级。

关键词：振荡器电子设备变容二极管变容管相位噪声有源法 SC

Refinement of saliva microRNA biomarkers for sports-related concussion

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Journal of Sport and Health Science 2023年第3期12卷 369-378页

作者： Steven D.Hicks Cayce Onks raymond Y.Kim Kevin J.Zhen Jayson loeffert Andrea C.loeffert Robert P.Olympia Gregory Fedorchak Samantha DeVita Zofia Gagnon Callan Mcloughlin Miguel M.Madeira Scott l.Zuckerman Timothy lee Matthew Heller Chuck Monteith Thomas R.Campbell Christopher Neville Elise Fengler Michael N.Dretsch Department of Pediatrics College of MedicinePennsylvania State UniversityHersheyPA 17033USA Department of Orthopaedics and Rehabilitation College of MedicinePennsylvania State UniversityHersheyPA 17033USA Department of Family Medicine College of MedicinePennsylvania State UniversityHersheyPA 17033USA Department of Emergency Medicine College of MedicinePennsylvania State UniversityHersheyPA 17033USA Department of Research and Development Quadrant Biosciences Inc.SyracuseNY 13210USA Department of Biology Marist CollegePoughkeepsieNY 12601USA Sports Concussion Center College of MedicineVanderbilt UniversityNashvilleTN 37212USA Department of Family Medicine College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNY 11568USA Department of Athletic Training Colgate UniversityHamiltonNY 13346USA Department of Rehabilitation Sciences Old Dominion UniversityNorfolkVA 23529USA Department of Physical Therapy Education Orthopedicsand NeuroscienceCollege of MedicineSUNY Upstate Medical UniversitySyracuseNY 13210USA Department of Exercise Science Syracuse UniversitySyracuseNY 13210USA Department of Medical Research—West Walter Reed Army Institute of ResearchUS Army Joint Base Lewis-McChordHillhurstWA 98433USA

Background:Recognizing sport-related concussion(SRC)is challenging and relies heavily on subjective symptom *** objective,biological marker could improve recognition and understanding of *** is emerging evidence that salivary micro-ribonucleic acids(miRNAs)may serve as biomarkers of concussion;however,it remains unclear whether concussion-related miRNAs are impacted by *** sought to determine whether40 miRNAs previously implicated in concussion pathophysiology were affected by participation in a variety of contact and non-contact *** goal was to refine a miRNA-based tool capable of identifying athletes with SRC without the confounding effects of ***:This case-control study harmonized data from concussed and non-concussed athletes recruited across 10 *** of salivary miRNAs within 455 samples from 314 individuals were measured with RNA ***-subjects testing was used to identify and exclude miRNAs that changed with either(a)a single episode of exercise(166 samples from 83 individuals)or(b)season-long participation in contact sports(212 samples from 106 individuals).The miRNAs that were not impacted by exercise were interrogated for SRC diagnostic utility using logistic regression(172 samples from 75 concussed and 97 non-concussed individuals).Results:Two miRNAs(miR-532-5p and miR-182-5p)decreased(adjusted ple episode of exercise,and 1 miRNA(miR-4510)increased only after contact sports ***-three miRNAs changed at the end of a contact sports *** of these miRNAs(miR-26b-3p and miR-29c-3p)were associated(R>0.50;adjusted ple football *** the 15 miRNAs not confounded by exercise or season-long contact sports participation,11 demonstrated a significant difference(adjusted played moderate ability(area under curve>0.70)to identify concussion.A

关键词： Biomarker Contact sports Football RNA Traumatic brain injury

四点安装的SC切和AT切谐振器的加速度和加热特性

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宇航计测技术 1983年第S1期 57-63页

作者： raymond l.Flller John R.Vig 李自忠

本文研究了四点安装的 SC 切和 AT 切谐振器的加速度灵敏度和加热特性。加速度的灵敏度是根据振动引起的边带来确定的。每一个谐振器的测量结果均与振动方向和振动频率呈函数关系。所研究的谐振器的参数包括:切角（AT 和 SC）、固定方... 详细信息

本文研究了四点安装的 SC 切和 AT 切谐振器的加速度灵敏度和加热特性。加速度的灵敏度是根据振动引起的边带来确定的。每一个谐振器的测量结果均与振动方向和振动频率呈函数关系。所研究的谐振器的参数包括:切角（AT 和 SC）、固定方位、泛音次数、晶片的几何形状（平平的、平凸的、双凸的）、安装支架的刚度和晶片材料（天然石英、人造石英和经扫掠的人造石英）。预热特性的测量是,先把谐振器浸入冰水中,然后迅速将其浸入沸水中,等达到热均衡之后,用晶体阻抗表（CI-meter）监测谐振器频率。对不同的 AT 和 SC 切设计（基模和三次泛音）的预热时间作了比较。可以看出,四点安装的陶瓷扁平封装的 SC 切谐振器能够在20秒内从0℃预热到100℃,而频率在2×10-7以内。

关键词：谐振器基模共振器基本模激光模加速度灵敏度 AT SC 加热特性

The Fish Fauna of the Future large Size Reservoir of Ouessa, on the Mouhoun River, Burkina Faso

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Advances in Bioscience and Biotechnology 2021年第10期12卷 309-322页

作者： raymond Ouedraogo Florent M. Y. Sawadogo Nomwine Da Komandan Mano INERA-Institut de l’Environnement et de Recherches Agricoles Ouagadougou Burkina Faso laboratoire de Biologie et d’Ecologie Animales Université Joseph KI-ZERBO Ouagadougou Burkina Faso Université de Dédougou Dédougou Burkina Faso

Reliable and basic information on fish are required for the sustainable management of a fishery. For this reason, the fish fauna of the future reservoir of Ouessa in the low section of the Mouhoun River, Burkina Faso is studied. In order to describe the fish community, the fish were sampled in March 2020 thanks to cast nets and gill nets. They were sorted into species and each fish was weighted at the nearest 0.1 g and its total length measured at the nearest mm. The landings of commercial fishermen were also observed. In total, 1059 fishes were collected and grouped into 42 species, 27 generas and 16 families. The dominant species were Synodontis nigrita, Synodontis schall, Marcusenius senegalensis, Schilbe intermedius, Brycinus nurse and Alestes baremoze. However, the compilation of diverse sources suggests the presence of nearly 70 species. The index of Shannon-Weaver (3.97), the values of the condition factor, the fish size and the presence of intolerant species indicate the relatively good conditions of the aquatic ecosystem. Among the 24 dominant species, 54% have a positive allometric growth, 42% a negative allometric growth and 0.04 an isometric growth. This study builds the basis of sustainable management of the future reservoir of Ouessa that is planned to be the largest one of the country (40,000 ha large).

关键词： Ichthyofauna Reservoir Ouessa Mouhoun River Burkina Faso

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珊瑚变白现象和海洋“热点”

人类环境杂志 1994年第3期23卷 176-180页

作者： Tomas J.Goreau raymond l.Hayes 蒋逸航全球珊瑚礁联盟主席和牙买加内格里尔珊瑚保护协会霍华德大学医学院解剖学系

全球海面温度图显示出在1983—1991年期间,在高于上一个温暖季节的长期月平均1℃以上的正异常("热点")之后,出现大批珊瑚礁变白的事件。热点的不规则形成、移动和消失,使得人们无法对它作出详细的长期预报,但是可以由卫星数据实时地跟... 详细信息

全球海面温度图显示出在1983—1991年期间,在高于上一个温暖季节的长期月平均1℃以上的正异常("热点")之后,出现大批珊瑚礁变白的事件。热点的不规则形成、移动和消失,使得人们无法对它作出详细的长期预报,但是可以由卫星数据实时地跟踪这种现象。如果《气候变化框架公约》要达到其保护温度敏感的生态系统的目的,就需要对海洋热点和珊瑚变白现象进行监测。

关键词：珊瑚礁变白