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Application of probability distribution in order to fit the diameter and natural and man-made height of oak species in two stands in Hyrcanian forests

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International Journal of Biomathematics 2016年第3期9卷 293-301页

作者： farah Mohammadi Mir Mozaffar Fallahchai[ Seyed Armin Hashemi Department of Forestry Faculty of Natural Resources Lahijan Branch Islamic Azad University Lahijan Iran

In order to study the fitting of some characteristics like low diameter at breast height （DBH）, the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species in north of Guilan＇s forests, Tooshi and Radarposhte forests were selected. A 100% inventory was done on a one-hectare sample plot in Tooshi man-made forests and on a two-hectare sample plot in Radarposhte natural forests. The results from this study showed that, in order to fit the diameter and the height of the Oak trees in man-made stands, Johnson＇s SB and normal statistical distributions have more capabilities and the three-parameter gamma and the three- parameter Weibull distributions are appropriate for diameters and heights of the natural Oak trees in Radarposhte forest, respectively.

关键词： Fitting diameter height Oak Hyrcanian forests.

Biomaterial application strategies to enhance stem cell-based therapy for ischemic stroke

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World Journal of Stem Cells 2022年第12期14卷 851-867页

作者： Asmaa’Mohd Satar farah Amna Othman Suat Cheng Tan School of Health Sciences Health CampusUniversiti Sains MalaysiaKubang KerianKelantan 16150Malaysia

BACKGROUND Ischemic stroke is a condition in which an occluded blood vessel interrupts blood flow to the brain and causes irreversible neuronal cell *** of regenerative stem cells has been proposed as a novel therapy to restore damaged neural circuitry after ischemic stroke ***,limitations such as low cell survival rates after transplantation remain significant challenges to stem cellbased therapy for ischemic stroke in the clinical *** order to enhance the therapeutic efficacy of transplanted stem cells,several biomaterials have been developed to provide a supportable cellular microenvironment or functional modification on the stem cells to optimize their reparative roles in injured tissues or *** To discuss state-of-the-art functional biomaterials that could enhance the therapeutic potential of stem cell-based treatment for ischemic stroke and provide detailed insights into the mechanisms underlying these biomaterial *** The PubMed,Science Direct and Scopus literature databases were searched using the keywords of“biomaterial”and“ischemic stroke”.All topically-relevant articles were then screened to identify those with focused relevance to in vivo,in vitro and clinical studies related to“stem cells”OR“progenitor cells”OR“undifferentiated cells”published in English during the years of 2011 to *** systematic search was conducted up to September 30,*** A total of 19 articles matched all the inclusion *** data contained within this collection of papers comprehensively represented 19 types of biomaterials applied on seven different types of stem/progenitor cells,namely mesenchymal stem cells,neural stem cells,induced pluripotent stem cells,neural progenitor cells,endothelial progenitor cells,neuroepithelial progenitor cells,and *** potential major benefits gained from the application of biomaterials in stem cell-based therapy were noted as induction of structural and functional

关键词： Biomaterial Stroke Stem/progenitor cell therapy Tissue bioengineering Combined treatment

China’s Infrastructure Investments in Djibouti:Opportunities and Challenges

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China’s Infrastructure Investments in Djibouti:Opportunitie...

作者： Hassan farah Ali 华中师范大学

学位级别：硕士

在过去三十年的经济高速发展中,中国实现了稳定的增长。然而,在过去几十年中,中国生产行业的快速扩张造成了资源的短缺,为了应对这一需求,中国企业决定到国外寻找新的机会。非洲成为中国投资的机会之一。与中国建立了紧密关系的国家之... 详细信息

在过去三十年的经济高速发展中,中国实现了稳定的增长。然而,在过去几十年中,中国生产行业的快速扩张造成了资源的短缺,为了应对这一需求,中国企业决定到国外寻找新的机会。非洲成为中国投资的机会之一。与中国建立了紧密关系的国家之一是吉布提,中国在那里资助并实施了重大发展项目,如港口和自由贸易区、新的铁路线、水利项目等根据国际货币基金组织2017年的报告,中国投资所做的工作正在帮助促进吉布提的经济增长。吉布提的港口基础设施建设也是习近平主席提出的“一带一路”倡议的一部分。中国投资是非洲国家的希望,尤其是吉布提政府的希望,因为吉布提缺乏基础设施的资金。中国对吉布提基础设施的投资将刺激经济增长,为吉布提带来知识的传播,并为人们创造新的就业机会。

关键词：中国吉布提基础设施投资

Downlink Non-blind Channel Estimation Algorithms Under Massive Mimo

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Downlink Non-blind Channel Estimation Algorithms Under Massi...

作者： Suber Abdirahman farah 河北工业大学

学位级别：硕士

大规模多输入多输出(MIMO)技术可以带来更高的频谱效率和功率效率,是5G中最具潜力的方向之一。通过改进系统性能、用户调度和传输方案,信道估计很重要。此外,信道估计和调度通常包含高维矩阵计算,因此,大规模MIMO无线系统中的信道估计... 详细信息

大规模多输入多输出(MIMO)技术可以带来更高的频谱效率和功率效率,是5G中最具潜力的方向之一。通过改进系统性能、用户调度和传输方案,信道估计很重要。此外,信道估计和调度通常包含高维矩阵计算,因此,大规模MIMO无线系统中的信道估计和传输方案优化具有较高的复杂度。通过在基站中配置大量天线(100-1000根),可以将能量集中在小空间内,提高吞吐量,同时天线充分利用空间,同时使用相同的频率资源,多终端(16-64)并发通信以降低整体能量效率,但使用此特性的前提是基站必须在天线数量增加时专门估计下行信道,传统的信道估计方案会带来巨大的导频开销,并且信道估计变得几乎不可能。本论文主要讨论大规模MIMO下的下行非盲信道估计算法,MIMO模型采用多用户MIMO,工作在FDD模式。本论文的创新有以下几点:(1)针对无线信道提出一种自适应稀疏的结构化压缩感知改进算法,利用压缩感知技术可以利用稀疏特性重构信道矩阵。传统算法中的子空间追踪(SP)算法具有回溯机制,使其信号重构精度更高,但与其他算法一样,SP算法需要信号的稀疏性作为先验条件,在某些环境下难以获得稀疏性,因此该算法不适用于大规模MIMO环境。自适应稀疏匹配追踪(ASMP)算法在SP算法的改进基础上增加了稀疏自适应机制,所以ASMP更加实用其性能不能满足实际需要。将这些特点与ASMP算法相结合,采用非正交导频结构,进而提出一种基于块的BASMP算法。实验表明该BASMP算法不仅能像ASMP那样适应稀疏性,而且比ASMP算法更适合大规模MIMO环境。(2)信息集解码(ISD)算法是一种现有的改进凸优化算法,为此本文在ISD算法的基础上提出一种改进的信道估计算法,该算法利用大规模MIMO信道中的空间相关性,通过发射非正交导频实现信道估计。所提出的结构化迭代支持检测(SISD)算法首先通过交替平方,并使用交替方向方法(ADM)解决基追踪(BP)问题,通过阈值检测策略更新初始信号支持集,最后通过三个过程交替执行几次后,信号结构将确定最终的支持集,并得到稀疏信道矩阵估计值。实验表明该改进算法可以通过不断迭代更新支持集,取得理想的信道估计效果。(3)提出一种改进的信道反馈算法以减少反馈开销。用户获取下行CSI后,需要通过上行信道将其作为信号反馈给BS,进行波束赋形、资源分配等过程。现在比较常用的是基于压缩感知技术的反馈方案,但是随着大规模MIMO中天线数量的增加,会导致反馈开销过大,并且反馈链路带宽有限,所以提出一种基于压缩感知的下行信道、差分运算估计和反馈算法,首先在用户端使用压缩感知技术估计下行信道矩阵,然后对任意两个相邻符号进行差分运算,得到信道矩阵的差分值,最后通过上行链路将差值作为信号压缩反馈给基站。实验表明是切实可行的。

关键词：大规模MIMO 信道估计压缩感知凸优化算法信道反馈

Two-vector Dimensionless Model Predictive Control of PMSM Drives Based on Fuzzy Decision Making

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CES Transactions on Electrical Machines and Systems 2022年第4期6卷 393-403页

作者： Nabil farah Gang Lei Jianguo Zhu Youguang Guo the School of Electrical and Data Engineering University of Technology Sydney(UTS) NSW 2007Australia IEEE the School of Electrical and Data Engineering University of Technology SydneyNSW 2007Australia the School of Electrical and Information Engineering University of SydneyNSW2006Australia

Model predictive controls(MPCs) with the merits of non-linear multi-variable control can achieve better performance than other commonly used control methods for permanent magnet synchronous motor(PMSM) ***,the conventional MPCs have various issues,including unsatisfactory steady-state performance,variable switching frequency,and difficult selection of appropriate weighting *** paper proposes two different improved MPC methods to deal with these *** method is the two-vector dimensionless model predictive torque control(MPTC).Two cost functions(torque and flux) and fuzzy decision-making are used to eliminate the weighting factor and select the first optimum *** torque cost function selects a second vector whose duty cycle is determined based on the torque *** other method is the two-vector dimensionless model predictive current control(MPCC).The first vector is selected the same as in the conventional MPC *** separate current cost functions and fuzzy decision-making are used to select the second vector whose duty cycle is determined based on the current *** proposed methods utilize the space vector PWM modulator to regulate the switching *** simulation results show that the proposed methods have better steady-state and transient performances than the conventional MPCs and other existing improved MPCs.

关键词： Electrical drives Permanent magnet synchronous motors Model predictive control

Prediction of C-glycosylated apigenin （vitexin） biosynthesis in Ficus deltoidea based on plant proteins identified by LC-MS/MS

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Frontiers in Biology 2017年第6期12卷 448-458页

作者： farah Izana Abdullah Lee Suan Chua Zaidah Rahmat Metabolites Profiling Laboratory Institute of Bioproduct Development Universiti Teknologi Malaysia 81310 UTM Skudai Johor BahruJohor Malaysia Department of Bioprocess and Polymer Engineering Faculty of Chemical and Energy Engineering Universiti Teknologi Malaysia 81310UTM Skudai Johor Bahru Johor Malaysia Department of Biotechnology and Medical Engineering Faculty of Biosciences & Medical Engineering Universiti Teknologi Malaysia81310 UTM Skudai Johor Bahru Johor Malaysia

Plant secondary metabolites act as defence molecules to protect plants from biotic and abiotic stresses. In particular, C-glycosylated flavonoids are more stable and reactive than their O-glycosylated counterparts. Therefore, vitexin (apigenin 8-C glucoside) present in Ficus deltoidea is well-known for its antioxidant, anti-inflammatory, and antidiabetic properties. Phenol based extraction was used to extract proteins (0.05% yield) with less plant pigments. This can be seen from clear protein bands in gel electrophoresis. In-gel trypsin digestion was subsequently carried out and analysed for the presence of peptides by LC-MS/MS. Thirteen intact proteins are identified on a 12% polyacrylamide gel. The mass spectra matching was found to have 229 proteins, and 11.4% of these were involved in secondary metabolism. Proteins closely related to vitexin biosynthesis are listed and their functions are explained mechanistically. Vitexin synthesis is predicted to involve plant polyketide chalcone synthase, isomerization by chalcone isomerase, oxidation by cytochrome P450 to convert flavanone to flavone, and transfer of sugar moiety by C-glycosyltransferase, followed by dehydration to produce flavone-8-C-glucosides. Phenol based extraction, followed by gel electrophoresis and LC-MS/MS could identify proteome explaining vitexin biosynthesis in F. deltoidea. Many transferases including β-1,3-galactosyltransferase 2 and glycosyl hydrolase family 10 protein were detected in this study. This explains the importance of transferase family proteins in Cglycosylated apigenin biosynthesis in medicinal plant.

关键词： C-glycosylation vitexin apigenin 8-C glucoside proteins peptides LC-MS/MS

Development of a new connection for precast concrete walls subjected to cyclic loading

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 97-117页

作者： Ramin Vaghei Farzad Hejazi Hafez Taheri Mohd Saleh Jaafar farah Nora Aznieta Abdul Aziz Civil Department Engineering Faculty University Putra Malaysia Serdang Selangor 43400 Malaysia

The Industrialized Building System （IBS） was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures is an important factor that ensures stability of buildings subjected to dynamic loads from earthquakes, vehicles, and machineries. However, structural engineers still lack knowledge on the proper connection and detailed joints o fiBS structure construction. Therefore, this study proposes a special precast concrete wall-to-wall connection system for dynamic loads that resists multidirectional imposed loads and reduces vibration effects （PI2014701723）. This system is designed to connect two adjacent precast wall panels by using two steel U-shaped channels （i.e., male and female joints）. During casting, each joint is adapted for incorporation into a respective wall panel after considering the following conditions： one side of the steel channel opens into the thickness face of the panel; a U-shaped rubber is implemented between the two channels to dissipate the vibration effect; and bolts and nuts are used to create an extension between the two U-shaped male and female steel channels. The developed finite element model of the precast wall is subjected to cyclic loads to evaluate the performance of the proposed connection during an imposed dynamic load. Connection performance is then compared with conventional connections based on the energy dissipation, stress, deformation, and concrete damage in the plastic range. The proposed precast connection is capable of exceeding the energy absorption of precast walls subjected to dynamic load, thereby improving its resistance behavior in all principal directions.

关键词： industrial building system precast concrete structure precast wall connection finite element method nonlinear analysis energy dissipation concrete damage plasticity

Coinciding anomalous coronary artery and papillary fibroelastoma

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Journal of Geriatric Cardiology 2016年第11期13卷 924-926页

作者： Saif Ibrahim Nachiket Patel farah Al-Saffar Jean Touchan Division of Cardiology Department of Medicine University of Florida-Jacksonville Jacksonville Florida USA Division of Cardiology DePartment of Medicine Mayo Clinic Scottsdale Arizona USA Division of Cardiology Department of Medicine University of Kentucky Lexington Kentucky USA

The primary cardiac tumors are extremely rare tumors that arise from the normal cardiac tissues. There are benign variants （mostly myxoma） and malignant tumors. Fibroelastoma （FE） is the most common primary tumor,... 详细信息

关键词： Anomalous coronary artery Cardiac tumors Fibroelastoma Valvular tumors

NLP-Based Subject with Emotions Joint Analytics for Epidemic Articles

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Computers, Materials & Continua 2022年第11期73卷 2985-3001页

作者： Woo Hyun Park Isma farah Siddiqui Dong Ryeol Shin Nawab Muhammad Faseeh Qureshi Department of Electrical and Computer Engineering Sungkyunkwan UniversitySuwon16419Korea Department of Software Engineering Mehran University of Engineering&TechnologyJamshoroPakistan Department of Computer Education Sungkyunkwan UniversitySeoul03063Korea

have been focused on addressing the Covid-19 pandemic;for example,governments have implemented countermeasures,such as quarantining,pushing vaccine shots to minimize local spread,investigating and analyzing the virus’characteristics,and conducting epidemiological investigations through patient management and ***,researchers worldwide require funding to achieve these ***,there is a need for documentation to investigate and trace disease ***,it is time consuming and resource intensive to work with documents comprising many types of unstructured ***,in this study,natural language processing technology is used to automatically classify these *** used statistical methods include data cleansing,query modification,sentiment analysis,and ***,owing to limitations with respect to the data,it is necessary to understand how to perform data analysis suitable for medical *** solve this problem,this study proposes a robust in-depth mixed with subject and emotion model comprising three *** first is a subject and non-linear emotional module,which extracts topics from the data and supplements them with emotional *** second is a subject with singular value decomposition in the emotion model,which is a dimensional decomposition module that uses subject analysis and an emotion *** third involves embedding with singular value decomposition using an emotion module,which is a dimensional decomposition method that uses emotion *** accuracy and other model measurements,such as the F1,area under the curve,and recall are evaluated based on an article on Middle East respiratory syndrome.A high F1 score of approximately 91%is *** proposed joint analysis method is expected to provide a better synergistic effect in the dataset.

关键词： Computational linguistic AI epidemic healthcare classification