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Compressible flow characteristics around a biconvex arc airfoil in a channel

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Propulsion and Power Research 2014年第1期3卷 29-40页

作者： md.abdul Hamid A.B.M.Toufique Hasan S.M.Alimuzzaman S.Matsuo T.Setoguchi Department of Mechanical Engineering Bangladesh University of Engineering and Technology(BUET)Dhaka-1000Bangladesh Department of Advanced Technology Fusion Saga UniversitySaga 8408502Japan

Shock wave-boundary layer interactions(SWBLI)are observed in several practical high-speed internal flows,such as compressor blades,turbine cascades,nozzles and so *** induced oscillations(SIO),aerodynamic instabilities so-called buffet flows,flutter,aeroacoustic noise and vibration are the detrimental consequences of this unsteady shockboundary layer *** the present study,a numerical computation has been performed to investigate the compressible flow characteristics around a 12%thick biconvex circular arc airfoil in a two dimensional *** averaged Navier-Stokes equations with two equation k-ωshear stress transport(SST)turbulence model have been applied for the computational *** flow field characteristics has been studied from pressure ratio(ratio of back pressure,pb to inlet total pressure,p01)of 0.75 to *** present computational results have been compared and validated with the available experimental *** results showed that the internal flow field characteristics such as shock wave structure,its behavior(steady or unsteady)and the corresponding boundary layer interaction are varied with pressure ***-excited shock oscillation was observed at certain flow ***,the mode of unsteady shock oscillation and its frequency are varied significantly with change of pressure ratio.

关键词： Compressible flow Shock waves Shock induced oscillation Frequency Reynolds-averaged Navier-Stokes(RANS)

Sustainability Reporting Based on GRI Indicators

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Journal of Sustainable Business and Economics 2022年第1期5卷 1-13页

作者： md.Al Amin md.Razaul Islam md.abdul Halim Department of Accounting Mawlana Bhashani Science and Technology UniversityTangailBangladesh Department of Accounting&Information Systems University of DhakaBangladesh Department of Business Administration Mawlana Bhashani Science and Technology UniversityTangailBangladesh

Every company wants to make a profit in the short run but doesn’t think about the long *** environment and human resources are used by the companies but eventually,they will react in a repugnant *** environment is being polluted every day and it is a threat to human life as well as the *** assess the impact of activities being done by the companies,a non-governmental organization was established in Boston called Global Reporting Initiative(GRI)in ***(Global Reporting Initiative)established a sustainability reporting framework that provides a systematic guideline for the sake of companies to disclose their performance on the environmental,economic,and social degree of *** study will find out how responsible multinational(listed and non-listed)companies(MNC)in the case of sustainability reporting when they are consistently doing business in the environment of *** study was analyzed based on GRI(Global Reporting Initiative)guidelines towards their reporting on sustainability.A quantitative score from 0 to 3 was given for each of 84 performance indicators(9,30,and 45 exhibitors for environmental,economic,and social dimensions respectively)of the GRI 3 guidelines based on sustainability *** study reports that tidings on the economic degree are better compared to environmental and social *** deviation is reported in environmental and social dimensions,but less deviation is reported in economic dimensions by the selected companies as the ***,the reporting practices of Nestle Bangladesh Ltd are better than other selected companies.

关键词： Sustainability reporting GRI MNC Performance indicators

Ergodic Capacity Evaluation of Multi-Hop Decode-and-Forward MIMO-OFDM Relaying Network

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Computers, Materials & Continua 2021年第9期68卷 3133-3145页

作者： latif Jan Mohammad Haseeb Zafar abdul Waheed Mahdi Zareei Faisal Alanazi Department of Electrical Engineering University of Engineering&TechnologyPeshawar25120Pakistan Department of Information Technology Hazara UniversityMansehra21120Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Electrical Engineering Prince Sattam Bin Abdulaziz UniversityCollege of EngineeringAl Kharj16278Saudi Arabia

Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless communication systems as *** Multiple-Input Multiple-Output(MIMO)technology,which is included in the IEEE 802.16j standard,still holds the most crucial position in the 4G spectrum as it promises to improve the throughput,capacity,spectral,and energy efficiency of wireless communication systems in the *** makes MIMO a viable technology for delay constrained medical and health care *** paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward(DF)protocol MIMO-Orthogonal Frequency Division Multiplexing(OFDM)relaying *** MIMO-OFDM is highly valuable for modern high-speed wireless communication systems,especially in the medical sciences,its performance degrades in multi-hop relay ***,in this paper,an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been ***-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity(bits/s/Hz)for different SNR-dB values for single,2×2,4×4,and multi-hop DF MIMOOFDM *** presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.

关键词： Multiple-input multiple-output system decode-and-forward protocol orthogonal frequency division multiplexing ergodic capacity

Geotechnical forensic investigation of a slope failure on silty clay soil--A case study

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 501-517页

作者： Mohammad Abubakar NAVEED Zulfiqar ALI abdul QADIR Umar Naveed latif Saad HAMID Umar SARWAR Military College of Engineering National University of Sciences and TechnologyRisalpur 24080Pakistan School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaibe 5096Australia

Qila Bala Hisar is one of the noteworthy places of Peshawar,Khyber *** fort was constructed on a flled ground during the 18th century and it was renovated several times by the occupants ever ***,due to an earthquake of magnitude 7.3,the upper part of the south-western wall of the fort *** collapse of the wall was attributed to the failure of the retained *** research was undertaken to characterize the slope material,study causal factors of failure and evaluate remedial *** investigation involved conventional field and laboratory testing and geophysical investigation using electrical resistivity technique to evaluate the nature of ***,X-ray Diffraction and Scanning Electron Microscopy was used to study the slope material at a molecular level to evaluate the existence of swelling *** analysis has shown that excessive seepage of water caused by the poor maintenance of runoff and sewage drains is the causal factor triggered by the seismic event.A remedial strategy involving soil nails,micro piles and improvement of the surface drainage is recommended.

关键词： forensic geotechnical investigation slope failure slope analysis finite element method numerical analysis seismic loading Qila Bala Hisar

Competition and Profitability of Banks: Empirical evidence from the Middle East & North African (MENA) Countries

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Journal of Business Administration Research 2020年第2期3卷 26-37页

作者： Syed Moudud-Ul-Huq md.abdul Halim Tanmay Biswas Department of Business Administration Mawlana Bhashani Science and Technology University

This paper uses generalized method of moments(GMM),Least Squares(LS)and Generalized Linear Model(GLM)to examine the impact of competition on profitability of banks and Stochastic Frontier approach(SFA)is used to estimate of cost *** have used an unbalanced panel dataset from a sample of emerging economic MENA countries over the period between 2011 and *** find out that have a significant and negative impact of competition on profitability of *** empirical findings of this study suggest that(1)MENA banks should more improve the process of managing and monitoring the loan segment business;the result which reducing in the level of credit risk which leads to higher profitability(2)MENA banks should shrink higher level of banking sector development.(3)MENA banks should make full conduct of available funds to engage in various natures of businesses;if there is an issue of insolvency,robust government support would give protection to MENA ***,it also provides some compulsory policy implications which will be very much beneficial for a wide range of stakeholders.

关键词： Competition Profitability Credit Risk Z-score Lerner Index Panel Regression

Effects of pre-sowing treatments on seed germination of Melia azedarach

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Journal of Forestry Research 2010年第2期21卷 193-196,I0006页

作者： md.Salim Azad md.Zedan-Al-musa md.abdul Matin Forestry and Wood Technology Discipline Khulna University Centre for Tropical and Subtropical Agriculture and Forestry(CeTSAF) Georg-August-University

A germination experiment of pre-treated seeds of Melia azedarach was conducted in the nursery of Forestry and Wood Technology Discipline,Khulna University,*** seeds of Melia azedarach were collected from healthy trees of National Botanical Garden,Bangladesh and were treated with five pre-sowing treatments（control,immersion in cold water,immersion in hot water,scarification with sand paper,and immersion in concentrated H2SO4） on seed *** revealed that the germination rates of pre-sowing treated seeds were significantly increased compared to those in control,except for cold water *** highest germination success（80%） was found in scarification with sand paper,followed by 74% and 69% in immersion in H2SO4 and hot water treatment,*** started on 8-11 days and completed on 20-21 days of the germination period in all *** of variance showed the significance difference in germination success among the treatments but no significance difference in germination period among the *** water treatment may be recommended on seed germination of the species in rural Bangladesh.

关键词： germination Melia azedarach pre-sowing treatment seed

Fractional Order Linear Active Disturbance Rejection Control for Linear Flexible Joint System

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Computers, Materials & Continua 2022年第3期70卷 5133-5142页

作者： Ibrahim M.Mehedi Rachid Mansouri Ubaid M.Al-Saggaf Ahmed I.M.Iskanderani Maamar Bettayeb abdulah Jeza Aljohani Thangam Palaniswamy Shaikh abdul latif abdul latif Department of Electrical and Computer Engineering(ECE) King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Intelligent Engineering Systems(CEIES) King Abdulaziz UniversityJeddah21589Saudi Arabia L2CSP Laboratory Mouloud Mammeri UniversityTizi OuzouAlgeria Electrical&Computer Engineering Department University of SharjahUnited Arab Emirates Department of Nuclear Engineering King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Mathematics King Abdulaziz UniversityJeddah21589Saudi Arabia

A linear flexible joint system using fractional order linear active disturbance rejection control is studied in this *** this control scheme,the performance against disturbances,uncertainties,and attenuation is *** active disturbance rejection control(LADRC)is mainly based on an extended state observer(ESO)technology.A fractional integral(FOI)action is combined with the LADRC technique which proposes a hybrid control scheme like *** this FOI action improves the robustness of the standard *** set-point tracking of the proposed FO-LADRC scheme is designed by Bode’s ideal transfer function(BITF)based robust closed-loop concept,an appropriate pole placement *** effectiveness of the proposed FO-LADRC scheme is illustrated through experimental results on the linear flexible joint system(LFJS).The results show the enhancement of the robustness with disturbance ***,a comparative analysis is presented with the results obtained using the integer-order LADRC and FO-LADRC scheme.

关键词： Active disturbance rejection fractional calculus ADRC pole placement linear flexible joint system robust control

Effects of Tinospora tuberculata leaf methanol extract on seedling growth of rice and associated weed species in hydroponic culture

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Journal of Integrative Agriculture 2016年第7期15卷 1521-1531页

作者： Farzad Aslani abdul Shukor Juraimi Muhammad Saiful Ahmad-Hamdani Farahnaz Sadat Golestan Hashemi md Amirul Alam md.abdul Hakim md Kamal Uddin Department of Crop Science Faculty of Agriculture Universiti Putra Malaysia (UPM) Institute of Tropical Agriculture Universiti Putra Malaysia (UPM) School of Agriculture Science and Biotechnology Faculty of Bioresources and Food Industry Universiti Sultan Zainal Abidin Department of Land Management Faculty of Agriculture Universiti Putra Malaysia (UPM)

The study was conducted to evaluate the responses of rice and rice weed seedlings （barnyardgrass and weedy rice） at the three-leaf stage toTinospora tuberculata leaf methanol extract （3.12, 6.25 and 12.5 g L–1） under hydroponic culture. It shows that the leaf methanol extract had various degrees effects depending on target plant species and each tested index （biomass, root length, shoot length, transpiration volume, chlorophyla, chlorophylb and carotenoid contents）. The effec-tive concentration of the leaf extract capable of reducing 50% of rice growth was higher than those of target weed species. Moreover, the root length was more tolerant to leaf methanol extract in comparison to the other plant parameters measured. A greater reduction was observed in chlorophyla content compared to chlorophylb and carotenoid. The results revealed that the reduction of transpiration volume closely coincided with the magnitude of growth inhibition of tested plants. Ultra-fast liquid chromatography analysis revealed 11 of 32 peaks in chemical proifle, including benzoic acid, caffeic acid, chlorogenic acid, isoorientin, isovitexin, orientin,p-anisic acid, syringic acid,trans-cinnamic acid,trans-ferulic acid, and vitexin have the same retention time with those peaks of the extract. The amount of compounds was present in the range of between 4817 and 115.5 mg kg–1 dry weight （DW）. The concentration-response bioassay of al 11 individual compounds and their equimolar mixture against the seeds of barnyardgrass revealed their contribution in the alelopahic activity ofT. tuberculata leaf extract. The examined compounds and their combination exhibited various degrees of growth inhibitory effects on the early growth of barnyardgrass. Therefore, the speciifc number, concentration, combination and inhibitory activity of bioactive compounds leads to alelopathy activity ofT. tuberculata leaves which could be employable directly as a natural herbicide and its growth inhibitor compounds can be used

关键词： alelochemicals identiifcation and quantiifcation natural herbicide UFLC weed control

Genotypic Divergence, Photosynthetic Efficiency, Sodium Extrusion, and Osmoprotectant Regulation Conferred Salt Tolerance in Sorghum

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Phyton-International Journal of Experimental Botany 2023年第8期92卷 2349-2368页

作者： Ashaduzzaman Sagar md.Sabibul Haque md.Alamgir Hossain md.Nesar Uddin Jannat E.Tajkia md.Ashik Mia Toufika Hossain Shabi md.Solaiman Ali Fakir md.abdul Kader Walid Soufan md.Atikur Rahman Muhammad Aamir Iqbal Mohammad Sohidul Islam Ayman El Sabagh A.K.M.Zakir Hossain Department of Crop Botany Bangladesh Agricultural UniversityMymensingh2202Bangladesh Planning and Development Division Bangladesh Institute of Nuclear AgricultureMymensingh2202Bangladesh Department of Soil Science Bangladesh Agricultural UniversityMymensingh2202Bangladesh Agriculture and Food Technology Discipline School of AgricultureGeographyEnvironmentOcean and Natural SciencesUniversity of the South PacificSamoa Agriculture Discipline College of ScienceHealthEngineering and EducationMurdoch UniversityPerthWA 6150Australia Plant Production Department College of Food and AgricultureKing Saud UniversityRiyadh11451Saudi Arabia Grassland and Forage Division National Institute of Animal ScienceRural Development AdministrationCheonan31000Korea Department of Agronomy Faculty of AgricultureUniversity of Poonch RawalakotRawalakot12350Pakistan Department of Agronomy Hajee Mohammad Danesh Science and Technology UniversityDinajpurBangladesh Faculty of Agriculture Kafrelsheikh UniversityKafrelsheikh33516Egypt

Salt stress is one of the major limitations to modern agriculture that negatively inﬂuences plant growth and *** tolerant cultivar can provide excellent solution to enhance stress tolerance with plantﬁtness to unfavorable ***,this study was aimed to screen salt tolerant sorghum genotypes through evaluating of different morphological,biochemical,and physiological attributes in response to salinity *** this study,we have been evaluated total six sorghum genotypes including Hybrid sorgo,Debgiri,BD-703,BD-706,BD-707,and BD-725 under salt stress(12 dS m^(-1) NaCl).The response variables included length and weight of root and shoot,root:shoot ratio(RSR),photosynthesis(A),transpiration rate(E),elemental concen-trations(K^(+),Na^(+) and K^(+)/Na^(+)),photochemical efﬁciency of photosystem II(F_(v)/F_(m)),water use efﬁciency(WUE)and pigment content(chlorophyll a,and b).The results revealed that saline environment signiﬁcantly reduced all response variables under study of sorghum genotypes,however,Hybrid sorgo remained unmatched by recording the maximum root and shoot *** same genotype recorded higher photosynthetic efﬁciency which was attributed to Na^(+) extrusion,K^(+) uptake and higher K^(+)/Na^(+) ratio(1.8 at stress),while these mechanisms were not fully active in rest of ***,this study also implies the involvement of proline in imparting tolerance against saline environment in Hybrid sorgo ***,BD-703 remained the most salt sensitive genotype as evident from the minimum morphological growth traits and the least biosynthesis of ***ﬁndings open new research avenues for salt stress alleviation by identifying elite salt-to-lerant genotypes of sorghum for breeding programs.

关键词： Salinity tolerance sorghum photosynthesis proline ion accumulation genotypic variance