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Association between serum vitamin D levels and gastric cancer:A retrospective chart analysis

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World Journal of Gastrointestinal Oncology 2016年第9期8卷 688-694页

作者： Neil Vyas Rafael Ching Companioni Melik Tiba hassan alkhawam Carmine Catalano Robert Sogomonian Joel Baum Aaron Walfish Department of Internal Medicine Elmhurst Hospital Center Department of Gastroenterology Elmhurst Hospital Center

AIM To determine whether there is an increased risk of gastric adenocarcinoma associated with vitamin D deficiency(VDd).METHODS A retrospective case control study was performed of all patients diagnosed with gastric adenocarcinoma between 2005 and *** we excluded the patients without a documented vitamin D level,49 patients were included in our *** The average age of patients with gastric adenocarcinoma and documented vitamin D level was 64 years old(95%CI: 27-86) and average vitamin D level was 20.8 mg/d L(95%CI: 4-44).Compared to a matched control group,the prevalence of VDd/insufficiency in patients with gastric adenocarcinoma was significantly higher than normal vitamin D levels(83.7% vs 16.3%).Forty-one patients(83.7%) with adenocarcinoma showed VDd/insufficiency compared to 18(37%) patients with normal vitamin D level without gastric cancer(OR: 8.8,95%CI: 5-22,P value < 0.0001).The average age of males with gastric adenocarcinoma diagnosis was 60 years old vs 68 years old for females(P = 0.01).StageⅡ gastric adenocarcinoma was the most prevalent in our study(37%).CONCLUSION We reported a positive relationship between VDd and gastric adenocarcinoma,that is to say,patients with decreased VDd levels have an increased propensity for gastric adenocarcinoma.

关键词： Gastric cancer Adenocarcinoma Vitamin D

An Online Fake Review Detection Approach Using Famous Machine Learning Algorithms

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Computers, Materials & Continua 2024年第2期78卷 2767-2786页

作者： Asma hassan Alshehri Department of Computer Sciences College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia

Online review platforms are becoming increasingly popular,encouraging dishonest merchants and service providers to deceive customers by creating fake reviews for their goods or *** Sybil accounts,bot farms,and real account purchases,immoral actors demonize rivals and advertise their *** academic and industry efforts have been aimed at detecting fake/fraudulent product or service evaluations for *** primary hurdle to identifying fraudulent reviews is the lack of a reliable means to distinguish fraudulent reviews from real *** paper adopts a semi-supervised machine learning method to detect fake reviews on any website,among other *** reviews are classified using a semi-supervised approach(PU-learning)since there is a shortage of labeled data,and they are ***,classification is performed using the machine learning techniques Support Vector Machine(SVM)and Nave *** performance of the suggested system has been compared with standard works,and experimental findings are assessed using several assessment metrics.

关键词： Security fake review semi-supervised learning ML algorithms review detection

Model Reference Adaptive Controller for Simultaneous Voltage and Frequency Restoration of Autonomous AC Microgrids

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1194-1202页

作者： Farahnaz Ahmadi Yazdan Batmani hassan Bevrani Department of Electrical Engineering University of KurdistanSanandajIran

In an autonomous droop-based microgrid,the sys-tem voltage and frequency(VaF)are subject to deviations as load *** the existence of various control methods aimed at correcting system frequency deviations at the second-ary control level without any communication network,the chal-lenges associated with these methods and their abilities to simul-taneously restore microgrid VaF have not been fully *** this paper,a multi-input multi-output(MIMO)model ref-erence adaptive controller(MRAC)is proposed to achieve VaF restoration while accurate power sharing among distributed generators(DGs)is *** proposed MRAC,without any communication network,is designed based on two meth-ods:droop-based and inertia-based *** the microgrid,the suggested design procedure is started by defining a model reference in which the control objectives,such as the desired settling time,the maximum tolerable overshoot,and steady-state error,are ***,a feedback-feedforward con-troller is established,of which the gains are adaptively tuned by some rules derived from the Lyapunov stability *** some simulations in MATLAB/SimPowerSystem Tool-box,the proposed MRAC demonstrates satisfactory perfor-mance.

关键词： AC microgid communication-free secondary control droop-based method inertia-based method model reference adaptive controller(MRAC) simultaneous voltage and frequency restoration

Assessment of liquefaction potential based on shear wave velocity:Strain energy approach

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3733-3745页

作者： Mohammad hassan Baziar Mahdi Alibolandi School of Civil Engineering Iran University of Science and TechnologyTehran16846-13114Iran

Liquefaction assessment based on strain energy is significantly superior to conventional stress-based *** main purpose of the present study is to investigate the correlation between shear wave velocity and strain energy capacity of silty *** dissipated energy until liquefaction occurs was calculated by analyzing the results of three series of comprehensive cyclic direct simple shear and triaxial tests on Ottawa F65,Nevada,and Firoozkuh sands with varying silt content by weight and relative ***,the shear wave velocity of each series was obtained using bender element or resonant column ***,for the first time,a liquefaction triggering criterion,relating to effective overburden normalized liquefaction capacity energy(WL=s’c)to effective overburden stresscorrected shear wave velocity(eVs1)has been *** accuracy of the proposed criteria was evaluated using in situ *** results confirm the ability of shear wave velocity as a distinguishing parameter for separating liquefied and non-liquefied soils when it is calculated against liquefaction capacity energy(WL=s’c).However,the proposed WL=s’c-Vs1 curve,similar to previously proposed cyclic resistance ratio(CRR)-Vs1 relationships,should be used conservatively for fields vulnerable to liquefaction-induced lateral spreading.

关键词： Liquefaction Strain energy capacity Shear wave velocity Cyclic triaxial test Cyclic direct simple shear test Resonant column test Bender element test

Distributed Hybrid Model Predictive Secondary Control of DC Microgrids with Random Communication Disorders

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 925-935页

作者： Meysam Yaribeygi Zeinab Karami Qobad Shafiee hassan Bevrani the Department of Electrical Engineering K.N.Toosi University of TechnologyTehranIranand he is now with the Sportradar CompanyTrondheimNorway the Department of Engineering Cybernetics(ITK) Norwegian University of Science and Technology(NTNU)TrondheimNorway the Smart/Micro Grids Research Center Department of Electrical EngineeringUniversity of KurdistanSanandajIran

A reliable and robust communication network is essential to exchange information between distributed generators(DGs)and accurately calculate their control actions in microgrids(MGs).However,the integration of the communication network and MGs poses challenges related to the flexibility,availability,and reliability of the ***,random communication disorders such as time delays and packet loss can negatively impact the system ***,it is essential to design a suitable secondary controller(SC)with a fast dynamic response to restore voltage and appropriate powersharing,while ensuring that the effects of random communication disorders are *** this regard,an optimal distributed hybrid model predictive secondary control method is presented in this *** simulations are carried out in a mixed simulation environment based on MATLAB and OMNET++,by considering IEEE 802.11(Wi Fi)using the recently developed Internet networking(INET)*** the implemented application layer,the recovery Unit is responsible for reducing the impact of random communication *** effectiveness and performance of the proposed method in comparison with a conventional model predictive control are verified by simulation results.

关键词： Microgrid model predictive control random communication disorder secondary control

An Adaptive Data-driven Method Based on Fuzzy Logic for Determining Power System Voltage Status

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 707-718页

作者： Sirwan Shazdeh Hêmin Golpîra hassan Bevrani the SMGRC University of KurdistanSanandajIran Power Systems Modeling&Simulation Lab Department of Electrical EngineeringUniversity of KurdistanKurdistanSanandaj 66177-15175Iran

This paper proposes an adaptive method based on fuzzy logic that utilizes data from phasor measurement units(PMUs) to assess and classify generating-side voltage trajectories. The voltage variable and its associated derivatives are used as the input variables of a fuzzy-logic block. In addition, the voltage trajectory is compared with the pre-selected pilot-bus voltage to make a reliable decision about the voltage operational state. Different types of short-term voltage dynamics are considered in the proposed method. The fuzzy membership functions are determined using a systematic method that considers the current situation of the voltage trajectory. Finally, the voltage status is categorized into four classes to determine appropriate remedial actions. The proposed method is validated on a IEEE 73-bus power system in a MATLAB environment.

关键词： Fuzzy logic fault-induced delayed voltage recovery phasor measurement unit(PMU) short-term voltage stability situational awareness voltage classification

Existence and numerical approximation of a solution to frictional contact problem for electro-elastic materials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 201-219页

作者： Othman Baiz EL-hassan Benkhira Rachid Fakhar University Ibn Zohr Lab.ESERFP of OuarzazateMorocco University Moulay Ismail Faculty of SciencesLaboratory MACSESTMBP 3103Toulal-MeknesMorocco University Sultan Moulay Slimane Laboratory LS2MEPolydisciplary Faculty of Khouribga25000 KhouribgaMorocco

In this paper,a frictional contact problem between an electro-elastic body and an electrically conductive foundation is *** contact is modeled by normal compliance with finite penetration and a version of Coulomb’s law of dry friction in which the coefficient of friction depends on the *** addition,the effects of the electrical conductivity of the foundation are taken into *** model leads to a coupled system of the quasi-variational inequality of the elliptic type for the displacement and the nonlinear variational equation for the electric *** existence of a weak solution is proved by using an abstract result for elliptic variational inequalities and a fixed point ***,a finite element approximation of the problem is *** some regularity conditions,an optimal order error estimate of the approximate solution is ***,a successive iteration technique is used to solve the problem numerically and a convergence result is established.

关键词： piezoelectric material frictional contact variational Inequality fixed point process finite element method error estimation iteration method

Sedimentary facies analysis of a thin-bed-dominated turbidite succession in the Miocene Temburong Formation,Kampung Bebuloh,Labuan Island,Malaysia

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Journal of Palaeogeography 2024年第3期13卷 401-429页

作者： Farah Syafira Burhanuddin Meor Hakif Amir hassan Department of Geology Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia

Thin-bedded turbidites are important hydrocarbon-bearing reservoirs in many mature fields throughout the *** type of turbidite depositional setting strongly influences vertical and horizontal continuity of the ***,distinguishing between lobe and levee associated thin-bedded turbidites remains challenging due to their generally similar facies *** study aims to contribute some insights to this problem by conducting a detailed bed-scale facies analysis on the Early Miocene Temburong Formation exposed at Kampung Bebuloh,Labuan Island,Malaysia,which may uncover features that can help in differentiating between both depositional *** facies are recognized in the Temburong Formation,which are interpreted as low density turbidites(F1-F4),hybrid event beds(F5),and sustained turbidites(F6).Detailed facies and ichnology analysis reveal features which are consistent with a lobe fringe deposit rather than leveeassociated environment interpretation,including tabular bed geometries,presence of hybrid event beds,and the absence of thick-bedded channel-fill *** facies associations are identified and interpreted as representing sub-environments within an overall lobe depositional setting.A diverse trace fossil assemblage,comprising the Nereites ichnofacies is consistent with a deep marine *** identification of the Paleodictyon and Nereites sub-ichnofacies indicates a distal turbidite system setting,most likely lobe *** on the thick accumulation of FA2 and FA3 and no distinct observable vertical trend,the Early Miocene Temburong Formation in Labuan is interpreted as turbidites deposited at the fringes of lobe complexes rather than a single lobe *** works into the Temburong Formation in SW Labuan proposed a middle slope to proximal basin floor setting where the thin-bedded intervals were interpreted as potentially representing either levee deposits or the fringes of confined lobe ***

关键词： Facies analysis Trace fossils Depositional lobes Hybrid event beds Lobe fringe Temburong formation Thin-bedded turbidite

Phosphoric Acid Pretreatment and Saccharification of Paper Sludge as a Renewable Material for Cellulosic Fibers

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Journal of Renewable Materials 2024年第9期12卷 1573-1591页

作者： Samar El-Mekkawi Wafaa Abou-Elseoud Shaimaa Fadel Enas hassan Mohammad hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green *** waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic ***,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders *** address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and *** created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their *** results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 *** hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper ***,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar *** total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,*** study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity