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SNR and RSSI Based an Optimized Machine Learning Based Indoor Localization Approach:Multistory Round Building Scenario over LoRa Network

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Computers, Materials & Continua 2024年第8期80卷 1927-1945页

作者： Muhammad Ayoub Kamal Muhammad Mansoor Alam Aznida abu bakar Sajak Mazliham Mohd Su’ud Malaysian Institute of Information Technology(MIIT) Universiti Kuala LumpurKuala Lumpur50250Malaysia Faculty of Computing and Informatics Multimedia UniversityCyberjaya63100Malaysia Depertment of Computer Science DHA Suffa UniversityKarachiSindh75500Pakistan Riphah Institute of System Engineering(RISE) Faculty of ComputingRiphah International UniversityIslamabad46000Pakistan Malaysian France Institute(MFI) Universiti Kuala LumpurKuala Lumpur50250Malaysia Faculty of Engineering and Information Technology School of Computer ScienceUniversity of Technology SydneyUltimoNSW 2007Australia

In situations when the precise position of a machine is unknown,localization becomes *** research focuses on improving the position prediction accuracy over long-range(LoRa)network using an optimized machine learning-based *** order to increase the prediction accuracy of the reference point position on the data collected using the fingerprinting method over LoRa technology,this study proposed an optimized machine learning(ML)based *** signal strength indicator(RSSI)data from the sensors at different positions was first gathered via an experiment through the LoRa network in a multistory round layout *** noise factor is also taken into account,and the signal-to-noise ratio(SNR)value is recorded for every RSSI *** study concludes the examination of reference point accuracy with the modified KNN method(MKNN).MKNN was created to more precisely anticipate the position of the reference *** findings showed that MKNN outperformed other algorithms in terms of accuracy and complexity.

关键词： Indoor localization MKNN LoRa machine learning classification RSSI SNR localization

Properties of Bark Particleboard Bonded with Demethylated Lignin Adhesives Derived from Leucaena leucocephala Bark

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Journal of Renewable Materials 2024年第4期12卷 737-769页

作者： rafidah Md Salim Jahimin Asik Mohd Sani Sarjadi Wood Testing Laboratory Faculty of Tropical ForestryUniversity of Malaysia SabahKota KinabaluSabah88400Malaysia Industrial Chemistry Program Faculty of Science and Natural ResourcesUniversity of Malaysia SabahKota KinabaluSabah88400Malaysia

Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard *** of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative *** this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin *** results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar *** particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable ***,the demethylated lignin adhesive extracted from *** bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.

关键词： Bark particleboard properties demethylated lignin lignin adhesives Leucaena leucocephala bark particles

多盘连续可变工作间隙磁流变制动器仿真与验证

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重庆大学学报 2024年第8期47卷 26-38页

作者：李东恒王娜 Saiful Anuar abu bakar 宋万里马来西亚理工大学汽车发展中心马来西亚新山81310 马来西亚理工大学机械工程学院马来西亚新山81310 柳州职业技术大学机电工程学院广西柳州545006 东北大学机械工程与自动化学院沈阳110819

为提高磁流变制动器制动能效,提出一种多盘连续可变磁流变液工作间隙结构的磁流变制动器。在ANSYS workbench环境下完成不同电流、间隙状态下的三维静态磁场仿真,对磁场沿工作间隙分布状况进行分析,通过试验台架对制动器性能进行测试。... 详细信息

为提高磁流变制动器制动能效,提出一种多盘连续可变磁流变液工作间隙结构的磁流变制动器。在ANSYS workbench环境下完成不同电流、间隙状态下的三维静态磁场仿真,对磁场沿工作间隙分布状况进行分析,通过试验台架对制动器性能进行测试。结果表明,磁流变液工作区域磁矢量分布相对均匀,无明显积聚现象,磁路设计合理。理论与实验结果变化趋势基本吻合,但在电流较大时,两者之间误差呈逐渐增大趋势。制动力矩在0~2.5 A电流变化区间增速较快,而在2.5~4.0 A区间明显放缓,最大力矩达到146.4 N·m,较间隙未改变状态增加25.80%。设计的制动器TVR值达到48.81 kN·m/m^(3),较传统磁流变制动器结构更紧凑,力矩调节范围更广,设计思路及实验结论对磁流变制动器结构的进一步研究具有借鉴意义。

关键词：磁流变液楔形工作间隙连续可变制动性能

Life Threatening Stridor Due to Primary Laryngeal Tuberculosis

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第1期13卷 62-69页

作者： Siti Aisyah Mohamed Azreen Zaira abu bakar Mawaddah Azman Otorhinolaryngology Department Hospital Ampang Selangor Malaysia Otorhinolaryngology Department Faculty of Medicine Universiti Kebangsaan Malaysia Kuala Lumpur Malaysia Otorhinolaryngology Department Hospital Kuala Lumpur Kuala Lumpur Malaysia

Tuberculosis is a potentially serious infectious disease. In otorhinolaryngology practice, lymph node infection is the most common site of predilection followed by the larynx. Laryngeal tuberculosis (LTB) typically presents with dysphagia, odynophagia and hoarseness. We reported a case of primary LTB presenting with acute upper airway obstruction and respiratory distress mimicking acute supraglottitis which requires emergency tracheostomy. Therefore, in acute upper airway obstruction, the appropriate initial investigation should be done to rule out TB to make sure early treatment can be given and it may prevent complications of disease to the patient. .

关键词： Extra-Pulmonary Granulomatous Infection Malignancy Upper Airway

Performance Analysis of the Reconfigurable Intelligent Surfaces Communication Systems

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Journal of Communications and Information Networks 2024年第2期9卷 184-191页

作者： Omar abu Ella Department of Electrical and Electronic Engineering Misurata University2659 Zawiat AlmahjoubMisurataLibya

Reconfigurable intelligent surfaces (RIS) play a vital role in meeting the growing demand for higher data rates and reliability in wireless systems. This study focuses on analyzing the performance of RIS systems to gain a deeper understanding of their *** paper presents a mathematical analysis of the RIS system,deriving closed-form formulae that express its characteristics including signal-to-noise ratio(SNR)distribution,ergodic and effective capacity,outage,and error probability. The obtained formulae are newly derived and unconditionally valid solutions. Numerical results demonstrate a close agreement between the derived formulae and MonteCarlo simulation outcomes.

关键词： ergodic capacity effective capacity outage probability bit error rate Rayleigh fading channel RISassisted communication system

Correlation of Hamstring Tendon Size in Pre-Operative MRI Measurement with Intra-Operative Graft Size in Primary Anterior Cruciate Ligament (ACL) Reconstruction

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Journal of Biosciences and Medicines 2024年第3期12卷 150-158页

作者： Nurhanani abu bakar Mohamad Razip Sirat Hairiah Abas Saiful Safuan Md Sani Department of Orthopaedic Hospital Pakar Sultanah Fatimah Muar Malaysia Department of Orthopaedic Hospital Tengku Ampuan Rahimah Klang Malaysia Department of Radiology Hospital Pakar Sultanah Fatimah Muar Malaysia Department of Medicine Clinical Research Center Hospital Kuala Lumpur Kuala Lumpur Malaysia

Background: The size of Hamstring autograft of less than 8.0 mm in ACL re-construction is one of the key factors that may contribute to the failure of the graft. In this study, we are going to assess the correlation of pre-operative MRI measurement of Hamstring tendons with the intra-operative ACL graft. Thus, it may help surgeons to anticipate the needs for graft augmentation should the final graft size be smaller than expected. Methods: We retrospectively re-viewed 41 cases of ACL reconstructions in which MRI were done pre-operatively, in Hospital Pakar Sultanah Fatimah (HPSF), Muar between January 2019 until December 2022. MRI measurements of Hamstring tendon (semitendinosus: ST, and gracilis) were done by a radiologist, and the in-tra-operative notes were reviewed for the final graft size. Pearson’s correlation coefficients were calculated to determine the relationship between graft size and tendon cross-sectional area. The intraclass correlation (ICC) by using two-way mixed model with type consistency, the reliability based on average measure was 0.41 (95% CI: ?0.10, 0.69). A p-value < 0.05 was considered sig-nificant. Results: Of 105 patients with primary ACL reconstruction done be-tween January 2019 to December 2022, only 41 patients were included in this study. There was fair correlation (p = 0.048) between pre-operative MRI measurement and the graft diameter intra-operatively. The mean of 17.0 mm of combined diameter of ST and gracilis tendon in MRI may results in graft diameter of 8.3 mm. There was also positive correlation between patients’ height and the intra-operative graft size. Conclusion: These results showed good correlation between pre-operative MRI measurement of Hamstring ten-don size with the intra-operative graft size, hence it is a reliable tool to predict the Hamstring autograft size in ACL reconstruction.

关键词： ACL Reconstruction Pre-Operative MRI Hamstring Tendon

MXenes and heterostructures-based electrocatalysts for hydrogen evolution reaction:Recent developments and future outlook

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Journal of Energy Chemistry 2024年第5期92卷 176-206页

作者： Abdul Hanan Hafiz Taimoor Ahmed Awan Faiza Bibi Raja rafidah Raja Sulaiman Wai Yin Wong Rashmi Walvekar Seema Singh Mohammad Khalid Sunway Centre for Electrochemical Energy and Sustainable Technology(SCEEST) School of Engineering and TechnologySunway UniversityNo.5 Jalan UniversitiBandar Sunway47500 Petaling JayaSelangorMalaysia Fuel Cell Institute Universiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Faculty of Innovation and Technology School of EngineeringChemical Engineering ProgrammeNo.1 Jalan Taylor’sTaylor’s University Malaysia47500 Subang JayaSelangorMalaysia Chitkara Centre for Research and Development Chitkara UniversityHimachal Pradesh 174103India School of Applied and Life Sciences Uttaranchal UniversityDehradunUttarakhand 248007India Manipal Institute of Technology Manipal Academy of Higher EducationManipal 576104KarnatakaIndia Centre of Research Impact and Outcome Chitkara UniversityPunjab 140401India

The increasing focus on electrocatalysis for sustainable hydrogen(H_(2))production has prompted significant interest in MXenes,a class of two-dimensional(2D)materials comprising metal carbides,carbonitrides,and *** materials exhibit intriguing chemical and physical properties,including excellent electrical conductivity and a large surface area,making them attractive candidates for the hydrogen evolution reaction(HER).This scientific review explores recent advancements in MXene-based electrocatalysts for HER *** discusses various compositions,functionalities,and explicit design principles while providing a comprehensive overview of synthesis methods,exceptional properties,and electro-catalytic approaches for H_(2) production via electrochemical ***,challenges and future prospects in designing MXenes-based electrocatalysts with enhanced kinetics are highlighted,emphasizing the potential of incorporating different metals to expand the scope of electrochemical *** review suggests possible efforts for developing advanced MXenes-based electrocatalysts,particularly for efficient H_(2) generation through electrochemical water-splitting reactions..

关键词： MXenes Electrocatalyst Water Splitting Hydrogen Generation Clean Energy

Development of sustainable thermal insulation based on bio-polyester filled with date pits

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Journal of Bioresources and Bioproducts 2024年第1期9卷 74-89页

作者： Amal Mlhem Thomas Teklebrhan Evenezer Bokuretsion Basim abu-Jdayil Chemical&Petroleum Engineering Department United Arab Emirates UniversityPO Box 15551United Arab Emirates National Water and Energy Center United Arab Emirates UniversityPO Box 15551United Arab Emirates

Date palm pit(DPP)-filled poly(-hydroxybutyrate)(PHB)composites were prepared,evaluated,and characterized to determine their thermal insulation *** conductivity values ranged between 0.086 and 0.100 W/(m·K).At a maximum filler concentration(50%(w)),the specific heat capacity and thermal diffusivity were 1183 J/(kg·K)and 0.0689 mm^(2)/s,*** DPP increased the thermal stability,and the highest compressive strength obtained was 80 MPa at 30%filler *** PHB-DPP composites exhibited promising water absorption(less than 6%)and tensile strength(6-14 MPa).Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.

关键词： Green construction material Sustainable thermal insulator Date pit Polyhydroxybutyrate

对于非酒精性脂肪肝病的认识——基于亚洲人群的研究

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Gastroenterology Report 2016年第2期4卷 131-135,I0002页

作者： George B.B.Goh Clarence Kwan Sze Ying Lim Nanda KK Venkatanarasimha rafidah abu-bakar Thinesh L Krishnamoorthy Hang Hock Shim Kiang Hiong Tay Wan Cheng Chow Department of Gastroenterology&Hepatology Singapore General HospitalSingapore Duke-NUS Graduate Medical School Singapore Department of Diagnostic Radiology Singapore General HospitalSingapore

背景和目的:非酒性脂肪肝病(NAFLD)是最常见的慢性肝病,同时也是代谢综合征的一项危险因素。NAFLD在全球范围内的患病率基于地域差异在5%~30%不等。尽管流行病学资料显示代谢相关性疾病的患病率在新加坡呈快速增长,但对于该地区NAFLD的... 详细信息

背景和目的:非酒性脂肪肝病(NAFLD)是最常见的慢性肝病,同时也是代谢综合征的一项危险因素。NAFLD在全球范围内的患病率基于地域差异在5%~30%不等。尽管流行病学资料显示代谢相关性疾病的患病率在新加坡呈快速增长,但对于该地区NAFLD的数据却十分有限。本研究旨在了解新加坡NAFLD的患病率及公众对该病的认识。方法:本研究是一项横断面观察研究,旨在评估NAFLD患者的人口统计学、人体测量学及临床资料,研究对象来自于一项胃肠公众论坛的参会者。NAFLD的诊断基于超声学标准;代谢综合征的诊断则基于国际糖尿病联盟的指南。通过自行设计的调查问卷来了解大家对NAFLD这种疾病的看法。结果:共有227名研究对象纳入研究,其中40%被诊断为NAFLD。相对于那些非NAFLD人群,NAFLD者男性居多,年龄更大,体质指数更高,腰围更宽,患代谢性综合征的比例更高(均P0.05)。值得注意的是,75.6%的具有代谢危险因素者,并不认为自己存在NAFLD风险。结论:我们的研究显示NAFLD在新加坡具有较高的患病率,包括在那些非肥胖人群中。考虑到人们对NAFLD的发生风险认识不足,有必要加强公众教育,以提高人们对NAFLD的认识。

关键词：非酒精性脂肪肝病流行病学认识新加坡