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Voids size distribution in gelled waxy crude oil under dynamic and static cooling

Petroleum Research 2024年第1期9卷 109-114页

作者： girma t.chala Shaharin A.Sulaiman Department of Mechanical Engineering(Well Engineering) International College of Engineering and ManagementP.O.Box 2511C.P.O Seeb 111MuscatOman Department of Mechanical Engineering Universiti Teknologi PETRONASBandar Seri Iskandar37500TronohPerakMalaysia

Waxy crude oil is known for its high wax contents that can potentially result in gelling following sufficient cooling of the transportation line in the subsea bed at offshore *** gelling over the entire lines requires an accurately predicted restart pressure to restart the clogged and idle ***,the common way of predicting the restart pressure has been reported to result in over-designed and predicted piping *** research findings evidenced the formation of voids which would reduce the restart pressure *** study conducted in this paper is aimed at investigating the voids size distribution in gelled crude oil across and along transportation *** of experiments simulating crude oil transportation during both static and dynamic cooling were *** gelled crude oil below the pour point temperature was then scanned using a Magnetic Resonance Imaging(MRI)system to detect the voids *** resulting voids at each scanning cross-section were quantified,and their distributions were *** was observed that dynamic cooling had minimal impacts on the voids size difference along the pipeline with the difference in voids areas within 10 mm^(2) to be twice and uniform for the entire flow rates ***,voids size in statically cooled waxy crude oil was found to be highly distributed with a maximum of 6 voids size distribution in 10 mm2 *** low-end temperature had the highest size difference while the difference was decreasing with higher end *** study shows that the voids amount in dynamically cooled waxy crude oil could also be estimated with lower numbers of cross-sectional voids ***,the higher cross-sectional voids detection is recommended while estimating voids in statically cooled waxy crude oil.

关键词： Gelled crude oil Voids size distribution Dynamic cooling Static cooling

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BEC-BiLStM：面向危机事件的实时信息推文预测与知识图谱构建算法

BEC-BiLSTM：面向危机事件的实时信息推文预测与知识图谱构建算法

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作者： Nemera chala Dechasa 西安电子科技大学

学位级别：硕士

在危机情况下,如短期灾难或大流行(新冠肺炎-19)等长期事件,twitter可能是一个有价值的信息来源。社交媒体通常能以比官方新闻等传统来源快得多的速度提供有关变化的事实,也能提供关于事件的个人观点,如在危机和大规模紧急情况下的观点... 详细信息

在危机情况下,如短期灾难或大流行(新冠肺炎-19)等长期事件,twitter可能是一个有价值的信息来源。社交媒体通常能以比官方新闻等传统来源快得多的速度提供有关变化的事实,也能提供关于事件的个人观点,如在危机和大规模紧急情况下的观点或独特要求,twitter正越来越多地被用作一种流行的信息来源,用于交流和分享危机环境下的情况,报告受影响的人员和伤亡情况。该领域的最新研究证实,此类社交媒体信息可用于多项危机应对任务。因此,处理与危机相关的推文并预测信息推文对于改进危机应对和减少人员和财务损失至关重要。尽管社交媒体信息的可用性是巨大的、开放的和免费的,但由于其巨大的容量、多样性、速度、价值和可变性,在理解这些社交媒体数据方面存在很大的局限性。在危机事件期间,人们发布了大量信息和非信息推文。受影响的人员和个人、基础设施损坏、可用性和资源需求都包含在信息性推文中。在紧急情况下,在灾区或其他地方发现的人也会发布大量非信息性推文,这些推文不会向响应者提供重要信息。因此,开发一个可靠检测信息推文的系统至关重要。然而,由于推文长度短、缺乏足够的上下文和单词歧义,很难创建一个准确的模型来识别危机事件中的信息推文和常规推文。考虑到本论文面临的这些挑战,我们提出了一个深度学习模型,用于在危机事件期间从常规推文中预测信息性推文。本文提出的模型称为卷积层双向短时记忆编码器(BEC-Bi LStM)。该模型包含三层:第一层是用于从推文生成上下文单词嵌入的BERt层,第二层是用于局部特征提取的卷积层,最后一层是用于存储链接提取的上下文特征的Bi LStM层。除了这篇论文,我们还提出了一个知识图,用于显示相关见解,并在信息丰富的推文上生成实时视觉信息。为了验证我们的模型并将其与同行进行比较,我们在Crisislex-t6数据集上进行了实验。结果清楚地表明,拟议的BEC-Bi LStM在准确性和F1成绩方面优于同行。

关键词：内容丰富的推文 twitter 危机知识图谱深度学习

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Slow and Steady: the Cautious Use of Neuroleptics in a Patient with Andersen-tawil Syndrome

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Case Reports in Clinical Medicine 2022年第10期11卷 414-421页

作者： Fahad Alkhalfan Bharadwaj Adithya-Sateesh girma M. Ayele Merve Otles Rediet t. Atalay Miriam Michael Department of Internal Medicine University of Maryland Baltimore USA Department of Internal Medicine College of Medicine American University of Antigua Antigua Antigua and Barbuda Department of Internal Medicine Howard University Hospital Washington DC USA

Long Qt syndrome (LQt) is a disease of cardiac repolarization caused by alterations in the transmembrane potassium and sodium currents. this results in prolongation of the Qt interval on electrocardiography (EKG) and can result in torsade de pointes and sudden cardiac death. We present a case of a patient who has Anderson tawil syndrome;a congenital long Qt syndrome, with a history of cardiac arrhythmias who developed acute paranoid schizophrenia that was refractory to treatment with non-Qt-prolonging drugs and required institution of neuroleptics to control her psychiatric symptoms.

关键词： Long Q-t Schizophrenia Neuroleptic Anderson tawil Syndrome Congenital Long Qt Syndrome

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t2 mapping定量评价腰椎间盘退变的Meta分析

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磁共振成像 2022年第8期13卷 55-59,70页

作者：张旭胤郭银霞 PAXON Julien Michael ABDEtA Bogale girma 杜永浩牛刚西安交通大学第一附属医院影像科西安710061

目的利用Meta分析定量评估腰椎间盘退变髓核横向弛豫时间的变化规律。材料与方法检索自建库至2021年10月31日采用t2 mapping方法定量评估腰椎间盘退变的文献,英文数据库检索Cochrane Library、PubMed、EMBASE,中文数据库检索万方数据、... 详细信息

目的利用Meta分析定量评估腰椎间盘退变髓核横向弛豫时间的变化规律。材料与方法检索自建库至2021年10月31日采用t2 mapping方法定量评估腰椎间盘退变的文献,英文数据库检索Cochrane Library、PubMed、EMBASE,中文数据库检索万方数据、维普网、中国知网。采用RevMan 5.3和Stata 15.0软件计算不同等级腰椎间盘退变间髓核横向弛豫时间的加权均数差值(weighted mean difference,WMD)及其95%可信区间(confidential interval,CI)。结果共纳入文献13篇,包括Ⅰ级腰椎间盘362个,Ⅱ级腰椎间盘1418个,Ⅲ级腰椎间盘1006个,Ⅳ级腰椎间盘548个,Ⅴ级腰椎间盘201个。腰椎间盘髓核横向弛豫时间随着腰椎间盘退变等级的增加而逐渐下降。Ⅰ级横向弛豫时间明显高于Ⅱ级横向弛豫时间(WMD=35.58,95%CI:29.96~41.21,Pt2 mapping可作为辅助诊断腰椎间盘早期退变的影像学检查。

关键词： t2 mapping 横向弛豫时间磁共振成像腰椎椎间盘退变 Meta分析

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Iot-Enabled Autonomous System Collaboration for Disaster-Area Management

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1249-1262页

作者： Abenezer girma Niloofar Bahadori Mrinmoy Sarkar tadewos G.tadewos Mohammad R.Behnia M.Nabil Mahmoud Ali Karimoddini Abdollah Homaifar IEEE Department of Electrical and Computer Engineering North Carolina A&T State UniversityGreensboroNC 27411 USA

timely investigating post-disaster situations to locate survivors and secure hazardous sources is critical,but also very challenging and *** first responders putting their lives at risk in saving others,human-physical limits cause delays in response time,resulting in fatality and property *** this paper,we proposed and implemented a framework intended for creating collaboration between heterogeneous unmanned vehicles and first responders to make search and rescue operations safer and *** framework consists of unmanned aerial vehicles(UAVs),unmanned ground vehicles(UGVs),a cloud-based remote control station(RCS).A light-weight message queuing telemetry transport(MQtt)based communication is adopted for facilitating collaboration between autonomous *** effectively work under unfavorable disaster conditions,antenna tracker is developed as a tool to extend network coverage to distant areas,and mobile charging points for the UAVs are also *** proposed framework’s performance is evaluated in terms of end-to-end delay and analyzed using architectural analysis and design language(AADL).Experimental measurements and simulation results show that the adopted communication protocol performs more efficiently than other conventional communication protocols,and the implemented UAV control mechanisms are functioning *** scenarios are implemented to validate the overall effectiveness of the proposed framework and demonstrate possible use cases.

关键词： Architectural analysis and design language(AADL)and cloud computing disaster area management internet of things(Iot) message queuing telemetry transport(MQtt) unmanned aerial vehicle(UAV) unmanned ground vehicle(UGV)

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Stabilization of Expansive Soil Using Biomedical Waste Incinerator Ash

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Journal of Management Science & Engineering Research 2021年第2期4卷 49-58页

作者： Asefachew Belete tseganeh Henok Fikre Geberegziabher Ayele tesema chala African Railway Center of Excellence(ARCE) Addis Ababa Institute of Technology(AAiT)Addis Ababa University(AAU)Addis AbabaEthiopia School of Civil and Water Resource Engineering Woldia University Institute of TechnologyWoldiaEthiopia School of Civil and Environmental Engineering Addis Ababa Institute of Technology(AAiT)Addis Ababa University(AAU)Addis AbabaEthiopia Department of Structural and Geotechnical Engineering Széchenyi István UniversityEgyetem tér 1Gyor Hungary 9026

Expansive soils undergo high volume change due to cyclic swelling and shrinkage behavior during the wet and dry ***,such problematic soils should be completely avoided or properly treated when encountered as subgrade *** the present study,the biomedical waste incinerator ash and lime combination was proposed to stabilize expansive *** size analysis,Atterberg limits,free-swell,compaction,unconfined compression strength,and California bearing ratio tests were conducted on the natural soil and blended with 3%,5%,7%,9%,and 11%biomedical waste incinerator ash(BWIA).the optimum content of BWIA was determined based on the free-swell test *** further investigate the relative effectiveness of the stabilizer,2%and 3%lime were also added to the optimum soil-BWIA mixture and UCS and CBR tests were also *** addition,scanning electron microscopy(SEM)tests for representative stabilized samples were also conducted to examine the changes in microfabrics and structural arrangements due to *** addition of BWIA has a promising effect on the index properties and strength of the expansive *** strength of the expansive soil significantly increased when it was blended with the optimum content of BWIA amended by 2%and 3%lime.

关键词： Expansive soil Stabilization BWIA Subgrade CBR

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恩诺沙星在鲫鱼肝微粒体中的代谢及代谢关键酶

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生态毒理学报 2020年第3期15卷 64-70页

作者：刘婉玉 tadiyose girma Bekele 赵洪霞大连理工大学环境学院工业生态和环境工程教育部重点实验室大连116024

抗生素因具有抗菌谱广、杀菌性强等特点而被广泛应用于人类医药、畜牧业、农业和水产养殖业。其进入水生生物体内后,会在药物代谢酶的作用下发生代谢转化,产生生态毒性。采用鲫鱼肝微粒体体外孵育法,探究恩诺沙星细胞色素P450酶作用下... 详细信息

抗生素因具有抗菌谱广、杀菌性强等特点而被广泛应用于人类医药、畜牧业、农业和水产养殖业。其进入水生生物体内后,会在药物代谢酶的作用下发生代谢转化,产生生态毒性。采用鲫鱼肝微粒体体外孵育法,探究恩诺沙星细胞色素P450酶作用下的代谢转化过程,并通过代谢抑制实验确定关键的代谢酶。结果表明,恩诺沙星体外代谢过程符合一级动力学方程,当恩诺沙星暴露浓度为1 mg·L^-1时,其在肝微粒体中的消除速率常数(k)最大为0.00303 min^-1,半衰期(t1/2)最短为228.8 min,应用高效液相色谱串联质谱(HPLC-MS/MS)技术,检测到了恩诺沙星脱乙基产物和羟基化产物;代谢抑制实验结果表明,CYP3A4在恩诺沙星代谢过程中起主要作用,是恩诺沙星代谢的关键酶。本研究结果为深入了解恩诺沙星在水生生物体内的代谢转化及其生态风险提供了基础数据。

关键词：恩诺沙星鲫鱼微粒体体外代谢 CYP3A4

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Silvicultural alternatives to conventional even-aged forest man-agement-what limits global adoption?

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Forest Ecosystems 2015年第2期2卷 123-138页

作者： Klaus J Puettmann Scott McG Wilson Susan C Baker Pablo J Donoso Lars Dr?ssler girma Amente Brian D Harvey thomas Knoke Yuanchang Lu Susanna Nocentini Francis E Putz toshiya Yoshida Jürgen Bauhus Department of Forest Ecosystems and Society Oregon State University Consultant Forester and Forest Ecologist School ofBiological Sciences University of Tasmania Department of Forests and Society Faculty of Forest Sciences and Natural Resources Universidad Austral de Chile Southern Swedish Forest Research Centre Swedish Agricultural University Haramaya University Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue 445 Boulevard de l’Université Institute of Forest Management TUMSchool of Life Sciences Weihenstephan Technische Universit?t München Department of Forest Management and Statistics IFRIt Chinese Academy of Forestry Department of Agricultural Food and Forestry Systems University of Florence Department of Biology University of Florida Uryu Experimental Forest Field Science Center for Northern Biosphere Hokkaido University Chair of Silviculture Faculty of Environment and Natural Resources University of FreiburgTennenbacherstr

Background： the development of forestry as a scientific and management discipline over the last two centuries has mainly emphasized intensive management operations focused on increased commodity production, mostly wood. this conventionar＇ forest management approach has typically favored production of even-aged, single-species stands. While alternative management regimes have generally received less attention, this has been changing over the last three decades, especially in countries with developed economies. Reasons for this change include a combination of new information and concerns about the ecological consequences of intensive forestry practices and a willingness on the part of many forest owners and society to embrace a wider set of management objectives. Alternative silvicultural approaches are characterized by a set of fundamental principles, including avoidance of clearcutting, an emphasis on structural diversity and small-scale variability, deployment of mixed species with natural regeneration, and avoidance of intensive site-preparation methods. Methods： Our compilation of the authors＇ experiences and perspectives from various parts of the world aims to initiate a larger discussion concerning the constraints to and the potential of adopting alternative silvicultural practices. Results： the results suggest that a wider adoption of alternative silvicultural practices is currently hindered by a suite of ecological, economic, logistical, informational, cultural, and historical constraints. Individual contexts display their own unique combinations and relative significance of these constraints, and accordingly, targeted efforts, such as regulations and incentives, may help to overcome specific challenges. Conclusions： In a broader context, we propose that less emphases on strict applications of principles and on stand structures might provide additional flexibility and facilitate the adoption of alternative silvicultural regimes in a broader set of circumstanc

关键词： Natural Regeneration Forest Owner Stand Structure Commodity Production Private Landowner

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Effect of transport time and Handling on Physiological Responses of Cattle

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Journal of Agricultural Science and technology(A) 2012年第6期2卷 800-814页

作者： girma Gebresenbet Isabel Wikner Emmanuel Yaovi Hunnuor Bobobee Gustavo Maria Morris Villarroel Department of Energy and technology Swedish University of Agricultural Sciences Box 7032 Uppsala 75007 Sweden Department of Agricultural Engineering KNUST Ghana Universidad de Zaragoza Catedra de Produccion Animal Facultad de Veterinaria 50013 Zaragoza Spain

the objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to11 hours, and two space allowances (2 m2 and 1.5 m2 per animal for cows and bulls; and 1.2 m2 and 0.8 m2 per animal for calves) were used for the experiment during transport from farms to the abattoir in Uppsala, Sweden. Measurements were made on five animals on each trip. Stress response parameters considered were cortisol, glucose, lactate, creatine kinase and heart rate. Blood samples were taken before and after transport. Heart rate sensors were mounted on the animals at least 30 minutes before loading and measurements were made continuously from farms to the abattoirs until stunning. the results of heart rate measurement indicated that loading, un-loading and forced movement in the stunning box were the most stressful events. However, the results of statistical analysis confirmed that transport time doesn"t have significant effect (P ≤ 0.05) on heart rate. Concentration level of cortisol increased by 10 folds during short transport. However, cortisol concentration decreased with an increase of transport times (P ≤ 0.01). Glucose concentrations increased with transport time in all animal categories (P ≤ 0.01). transport time has significant effect on concentration levels of glucose (P ≤ 0.01), creatine kinase (P ≤ 0.001) and lactate (P ≤ 0.01) particularly after 6 hours journey time.

关键词：运输时间小牛生理反应动物福利肌酸磷酸激酶浓度增加速率传感器皮质醇

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Climate trends of temperature, Precipitation and River Discharge in the Abbay River Basin in Ethiopia

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Journal of Water Resource and Protection 2019年第10期11卷 1292-1311页

作者： Asaminew Abiyu Cherinet Denghua Yan Hao Wang Xinshan Song tianlin Qin Mulualem t. Kassa Abel girma Batsuren Dorjsuren Mohammed Gedefaw Hejia Wang Otgonbayar Yadamjav College of Environmental Science and Engineering Donghua University Shanghai China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research (IWHR) Beijing China Department of Water Resources China Institute of Water Resources and Hydropower Research (IWHR) Beijing China Bio-taq Economy Innovations (BiotEI) Inc. Winnipeg Canada Department of Natural Resource Management University of Gondar Gondar Ethiopia Department of Environment and Forest Engineering School of Engineering and Applied Sciences National University of Mongolia Ulaanbaatar Mongolia Department of Hydraulic Engineering Tsinghua University Beijing China Department of Sociology and Social Work School of Art & Sciences National University of Mongolia Ulaanbaatar Mongolia.

Projecting future changes of streamflow in the Abby River Basin (ARB) is important for planning and proper management of the basin system. the current study conducted in five stations of the Abbay river basin, and investigated the annual temperature, precipitation, and river discharge variability using the Innovative trend analysis method, Mann-Kendall, and Sen’s slope test estimator. the result showed a slightly increasing trend of annual precipitation in Assoa (Z = 0.71), Bahir Dar (Z = 0.13), and Gonder (Z = 0.26) stations, while a significant increasing trend was observed in Nedgo (Z = 2.45) and Motta (Z = 1.06) stations. Interestingly, the trend of annual temperature in Assosa (Z = 5.88), Bahir Dar (Z = 3.87), Gonder (Z = 4.38), Nedgo (Z = 4.77), and Motta (Z = 2.85) was abruptly increased. the average mean temperature has increased by 0.2°C in the past 36 years (1980 to 2016). the extreme high temperature was observed in the semi-dry zone of northern Ethiopia. During the study period, a significant declining trend of the river discharge was recorded, and the river discharge was sharply decreased from 1992 onwards. the results of the current study showed annual variability of river discharge, precipitation, and temperature of the study area of the basin that could be used as a basis for future studies.

关键词： Abbay River Basin Climate Change Ethiopia Precipitation River Discharge temperature

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