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Leveraging Sharding-Based Hybrid Consensus for Blockchain

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Computers, Materials & Continua 2024年第10期81卷 1215-1233页

作者： Hind Baageel md Mahfuzur Rahman Department of Information&Computer Science King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center(IRC)for Intelligent Secure Systems King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia

The advent of blockchain technology has transformed traditional methods of information exchange,shifting reliance from centralized data centers to decentralized *** blockchain’s decentralization and security are strengths,traditional consensus mechanisms like Proof of Work(PoW)and Proof of Stake(PoS)face limitations in *** achieves decentralization and security but struggles with scalability as transaction volumes grow,while PoS enhances scalability,but risks centralization due to monopolization by high-stake ***,a recent advancement in blockchain technology,addresses scalability by partitioning the network into shards that process transactions independently,thereby improving throughput and reducing ***,cross-shard communication,essential for transactions involving multiple shards,introduces challenges in coordination and fault *** research introduces a shard-based hybrid consensus model,PoSW,which combines PoW and PoS to mitigate the limitations of both *** integrating PoW’s fairness with PoS’s scalability in a shard-based blockchain,the proposed model addresses key issues of scalability and *** evaluate the model against state-of-the-art consensus algorithms,including Monoxide and Practical Byzantine Fault Tolerance(PBFT).The results show that the proposed PoSW model reduces communication overhead compared to PBFT and improves resource utilization over *** addition to performance gains,the security analysis demonstrates that the PoSW model provides robust defense against common blockchain attacks such as the 51%and Sybil attacks,*** proposed approach is particularly suited for applications like decentralized finance(DeFi)and supply chain management,which require both high scalability and robust *** contributions of this research include the development of the PoSW hybrid consensus mechanism,its comparative evaluation with leading algorithms,and a thorough

关键词： Blockchain consensus algorithm decentralized network

A frequency domain design of PID controller for an AVR system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第4期15卷 293-299页

作者： md Nishat ANWAR Somnath PAN Department of Electrical Engineering Indian School of Mines

We propose a new proportional-integral-derivative(PID) controller design method for an automatic voltage regulation(AVR) system based on approximate model matching in the frequency domain. The parameters of the PID controller are obtained by approximate frequency response matching between the closed-loop control system and a reference model with the desired specifications. Two low frequency points are required for matching the frequency response, and the design method yields linear algebraic equations, solution of which gives the controller parameters. The effectiveness of the proposed method is demonstrated through examples taken from the literature and comparison with some popular methods.

关键词： Automatic voltage regulation(AVR) PID controller Frequency response matching

Approach for Grid Connected PV Management:Advance Solar Prediction and Enhancement of Voltage Stability Margin Using FACTS Device

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Journal of Electronic Science and Technology 2020年第4期18卷 367-377页

作者： md.Masum Howlader Mohammad Rokonuzzaman md Tanbhir Hoq Aziz Un Nur Ibn Saif md Shahrukh Adnan Khan Mahfuj Howlader Department of Electrical and Electronic Engineering University of Asia PacificDhaka 1205 Tyndall National Institute University College CorkCork T12 K8AF School of Science and Engineering Canadian University of BangladesDhaka 1212 Department of Computer Science and Engineering University of DhakaDhaka 1000

The uncertainty in solar energy is different from conventional,dispatchable generation fuels and difficult to incorporate into the standard system operating *** the first part of this work,the machine learning algorithm is used to train models based on solar irradiance data and different meteorological weather information to predict the solar irradiance for different cities to validate the forecasting ***,the intermittent and inertialess nature of photovoltaic(PV)systems can produce significant power oscillations that can cause significant problems with dynamic stability of the power system and also limit the penetration capacity of PV into the *** the second part,it is shown that the residue-based power oscillation damping(POD)controller obviously improves the inter-area oscillation *** validity and effectiveness of the proposed controller are demonstrated on the three-machine two-area test system that combines the conventional synchronous generator and flexible alternating current transmission systems(FACTS)device using *** report overall puts an in-depth analysis with regard to the challenges of solar resources with integrating,planning,operating,and particularly the stability of the rest of the power grid,including existing generation resources,customer requirements,and the transmission system itself that will lead to an improved decision making in resource allocations and grid stability.

关键词： Renewable energy(RE) support vector regression thyristor controlled series capacitor

Antitumor activity of Aponogeton undulatus against Ehrilich ascites carcinoma in Swiss albino mice

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 431-438页

作者： md Reyazul Islam md BadrulAlam UmmeTamima Shayla Islam Jenny Department of Bioactive Materials Science Chonbuk National University567Baekje-daeroDeokjin-guJeonju-siJeollabuk-doRepublic of Korea Graduate School of Food Science & Biotechnology Kyungpook National University 80Daehak-raBuk-guDaeguRepublic of Korea Department of Pharmacy Atishlipankar University of Science & Technology College of Pharmacy Seoul National UniversityI Guanak-roGuanak-guSeoulRepublic of Korea

Objective:To investigate in vitro antioxidant and in vivo antitumor activity of the crude methanolic extract of Aponogeton undulatus(MAU) along with its various organic ***:Aponogeton undulatus leaves were successively extracted using methanol(MAU)and then fractionated by chloroform,ethyl acetate(EAU) and *** total antioxidant capacity,lipid peroxidation inhibition assay.1.1-diphenyl-2-picrylhydrazyl(DPPH) free radical scavenging assay and ferrous reducing power assessment were used to evaluate the antioxidant potential of the crude extract and its organic *** in vivo antitumor activity is evaluated against Ehrlich ascites carcinoma(EAC) cell bearing in Swiss albino ***:EAU showed the highest antioxidant capacity as(175.80±0.41)mg/g,IC_(50)value of DPPH scavenging activity was(38.84±0.02)μg/mL and also exhibited maximum lipid peroxidation inhibition activity with the IC_(50) value of(42.52±0.32)μg/mL than other *** results demonstrate that reducing power of the extract was concentration *** addition,EAU was administered at 50.100 and 200 mg/kg body weight respectively to EAC cell bearing mice and a significant(P<0.05)decrease in tumor volume,packed cell volume and viable cell count and also increased the life span(17.52% .42.53% and 62.05% ).Hematological profiles were restored to normal levels in MAU treated mice as compared to EAC control ***:The results were found to be significant and confirmed that the Aponogeton undulatus has remarkable antitumor activity with antioxidant potential.

关键词： Antioxidant Antitumor Ehrlich ascites carcinoma Aponogeton undulatus

Enhanced aboveground biomass by increased precipitation in a central European grassland

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Ecological Processes 2018年第1期7卷 435-447页

作者： md Lokman Hossain Carl Beierkuhnlein Department of Geography Hong Kong Baptist University15 Baptist University RoadKowloon TongHong Kong Global Change Ecology International Elite Study ProgrammeFaculty of BiologyChemistry and Earth SciencesUniversity of BayreuthUniversitätsstraße 3095440 BayreuthGermany Department of Environmental Protection Technology German University BangladeshGazipur 1702Bangladesh Department of Biogeography University of BayreuthUniversitätsstraße 3095440 BayreuthGermany

Background:Global climate change is projected to increase temperature and alter precipitation pattern,which could affect grassland ***-term observation at a field experiment can be a powerful approach to explore the impacts of climate change on biomass productivity in *** attempting to understand how climatic variability regulates biomass productivity,we analyzed long-term records of temperature and precipitation to examine how variation of temperature and precipitation across 19 years affect biomass ***:We established the experiment with 64 plots in two blocks and planted 31 species in 30 different *** harvested aboveground biomass twice a year,sorted biomass by functional groups,and weighed dry *** site was mown after each *** did not apply any fertilizer and *** linear regression model,we examined the influences of growing season temperature and precipitation on biomass ***:The results showed that aboveground biomass productivity in September and annual were significantly increased in post-drought(2003–2015).The relationships of aboveground biomass productivity with growing season precipitation were significantly *** results showed that aboveground biomass productivity in June and annual were sensitive to growing season *** relationships of aboveground biomass productivity of the functional group of grasses with early growing season temperature were significantly *** growing season precipitation had a significant positive effect on aboveground biomass productivity of the functional groups of grasses and ***-drought aboveground biomass productivity of the functional groups of grasses in June and September were declined,whereas legumes significantly increased,which suggests that the role of dominant grasses may shift by legumes with global climate ***:Our results highlight that early and late growing temperature and precipitat

关键词： Aboveground biomass BIODEPTH experiment Climate change Functional groups Grassland biodiversity Hay meadow Precipitation variability Temperate grassland Temperature variability

Efficient Feature Selection and Machine Learning Based ADHD Detection Using EEG Signal

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Computers, Materials & Continua 2022年第9期72卷 5179-5195页

作者： md.Maniruzzaman Jungpil Shin md.Al Mehedi Hasan Akira Yasumura School of Computer Science and Engineering The University of AizuAizuwakamatsuFukushima965-8580Japan Faculty of Humanities and Social Science Kumamoto UniversityChuo-kuKumamotoJapan

Attention deficit hyperactivity disorder(ADHD)is one of the most common psychiatric and neurobehavioral disorders in children,affecting 11%of children *** study aimed to propose a machine learning(ML)-based algorithm for discriminating ADHD from healthy children using their electroencephalography(EEG)*** study included 61 children with ADHD and 60 healthy children aged 7–12 *** morphological and time-domain features were extracted from EEG *** t-test(p-value<0.05)and least absolute shrinkage and selection operator(LASSO)were used to select potential features of children with ADHD and enhance the classification *** selected potential features were used in four ML-based algorithms,including support vector machine(SVM),k-nearest neighbors,multilayer perceptron(MLP),and logistic regression,to classify ADHD and healthy *** overall prevalence of boys and girls with ADHD was 48.9%and 56.5%,*** average age of children with ADHD was 9.6±1.8 *** results illustrated that the combination of LASSO with SVM classifier achieved the highest accuracy of 94.2%,sensitivity of 93.3%,F1-score of 91.9%,and AUC of *** results also illustrated that MLP was the second-best ML-based classifier,which gave 93.4%accuracy,91.7%sensitivity,91.1%F1-score,and 0.960 *** findings indicated that the combination of the LASSO-based feature selection method and SVM classifier can be a useful tool for selecting reliable/potential features and classifying ADHD and healthy *** proposed ML-based algorithms could be useful for the early diagnosis of children with ADHD.

关键词： ADHD feature extraction feature selection classification machine learning

Productivity comparison of radial lateral wells and horizontal snake wells applied to marine gas hydrate reservoir development

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Petroleum 2021年第4期7卷 407-413页

作者： md Nahin Mahmood Boyun Guo Department of Petroleum and Mining Engineering Chittagong University of Engineering&TechnologyChattogram4349Bangladesh Department of Petroleum Engineering University of LouisianaLafayetteLA70504USA

Development of marine gas hydrate resources presents a huge challenge to the energy industry owing to the well production complications such as wellbore collapse,sand production,and low *** lateral wells(RLW)and horizontal snake wells(HSW)have been proposed separately to mitigate these *** compare the productivity potentials of these two types of wells using the recently developed analytical models and field case data from a gas hydrate reservoir in the South China *** is concluded that RLW will yield slightly higher gas productivity than HSW under similar con*** analysis with the well models indicates that the productivity of RLW is directly proportional to the number of laterals,length of laterals,and radius of laterals,while the productivity of HSW is directly proportional to the length and radius of the horizontal *** decision of using RLW or HSW can be made based on economic analysis of well completion and production,which should be addressed in future studies.

关键词： Natural gas hydrate Radial lateral wells Horizontal snake wells Productivity

Sorbitol-based osmotic diarrhea:Possible causes and mechanism of prevention investigated in rats

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World Journal of Gastroenterology 2006年第47期12卷 7635-7641页

作者： md Shahidul Islam Ei Sakaguchi Laboratory of Animal Nutri-tion Faculty of Agriculture Okayama University 1-1-1 Tsushima-naka Okayama City 700-8530 Japan

AIM: To study the possible causes of sorbitol (S)-based diarrhea and its mechanism of reduction by rice gruel (RG) in cecectomized rats. METHODS: S was dissolved either in distilled water or in RG (50 g/L) and ingested as a single oral dose (1.2 g/kg body mass, containing 0.5 g/L phenol red as a re-covery marker) by S (control) and S + RG groups (n = 7), respectively. This dose is over the laxative dose for hu-mans. Animals were sacrificed exactly 1 h after dose in-gestion, without any access to drinking water. The whole gastro-intestinal tract was divided into seven segments and sampled to analyze the S and marker remaining in its ***: Gastric-emptying and intestinal transit were comparatively slower in the S + RG group. Also, the S absorption index in the 3rd and last quarter of the small intestine (24.85 ± 18.88% vs 0.0 ± 0.0% and 39.09 ± 32.75% vs 0.0 ± 0.0%, respectively, P < 0.05) was sig-nificantly higher in the S + RG group than in the control group. The S absorption index and the intestinal fluid volume are inversely related to each other. CONCLUSION: The intestinal mal-absorption of S is the main reason for S-based osmotic diarrhea. Where RG en-hanced the absorption of S through passive diffusion, the degree of diarrhea was reduced in cecectomized rats.

关键词： Cecectomized rat Sorbitol Diarrhea Rice gruel Phenol red

Mechanical and metallurgical properties of friction stir welded dissimilar joints of AZ91 magnesium alloy and AA 6082-T6 aluminium alloy

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Journal of Magnesium and Alloys 2019年第2期7卷 264-271页

作者： Sameer md Anil Kumar Birru National Institute of Technology ImphalManipurIndia

In the present research work,AZ91 magnesium alloy and AA6082-T6 aluminium alloy were joined by friction stir welding *** comparison of microstructure and mechanical properties between different joints by varying the different materials on advance and retreating sides were mainly *** different welds have been prepared to find the material mixing between the similar and dissimilar *** joint interfaces of the welds have been investigated by employing an optical microscope and scanning electron *** Mg was placed on advancing side(AS),more aluminium content was soluble in nugget zone than the case where Mg was placed on the retreating side(RS).Thin intermetallic layer in the joint interface of Mg/Al and thick intermetallic layer with poor adhesion of the aluminium and magnesium have been observed in the dissimilar joints varying the *** highest UTS of 172.3 MPa was found for Mg-Al when Mg was placed on AS and lower UTS of 156.25 MPa was obtained when Mg was placed on *** of 86 Hv and 89 Hv were observed in the Stir zone for the dissimilar AZ91 Mg alloy and AA6082-T6 Al alloy when AZ91Mg alloy was placed on the AS and on the RS *** was also carried out to find the mode of failure.

关键词： Friction stir welding Magnesium alloy Aluminium alloy Microstructure Mechanical properties