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Assessment of vegetation cover changes and the contributing factors in the Al-Ahsa Oasis using Normalized Difference Vegetation Index(NDVI)

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Regional Sustainability 2024年第1期5卷 42-53页

作者： walid CHOUARI Department of Geography College of ArtsKing Faisal UniversityAl-Ahsa31982Saudi Arabia Laboratory Syfacte Faculty of Arts and Humanities of SfaxUniversity of SfaxSfax1168-3000Tunisia

The abandonment of date palm grove of the former Al-Ahsa Oasis in the eastern region of Saudi Arabia has resulted in the conversion of delicate agricultural area into urban *** current state of the oasis is influenced by both expansion and degradation ***,it is important to study the spatiotemporal variation of vegetation cover for the sustainable management of oasis *** study used Landsat satellite images in 1987,2002,and 2021 to monitor the spatiotemporal variation of vegetation cover in the Al-Ahsa Oasis,applied multi-temporal Normalized Difference Vegetation Index(NDVI)data spanning from 1987 to 2021 to assess environmental and spatiotemporal variations that have occurred in the Al-Ahsa Oasis,and investigated the factors influencing these *** study reveals that there is a significant improvement in the ecological environment of the oasis during 1987–2021,with increase of NDVI values being higher than *** 2021,the highest NDVI value is generally above 0.70,while the lowest value remains largely ***,there is a remarkable increase in NDVI values between 0.20 and *** area of low NDVI values(0.00–0.20)has remained almost stable,but the region with high NDVI values(above 0.70)expands during 1987–***,this study finds that in 1987–2002,the increase of vegetation cover is most notable in the northern region of the study area,whereas from 2002 to 2021,the increase of vegetation cover is mainly concentrated in the northern and southern regions of the study *** 1987 to 2021,NDVI values exhibit the most pronounced variation,with a significant increase in the“green”zone(characterized by NDVI values exceeding 0.40),indicating a substantial enhancement in the ecological environment of the *** NDVI classification is validated through 50 ground validation points in the study area,demonstrating a mean accuracy of 92.00%in the detection of vegetation *** general,both the user’s and produce

关键词： Normalized Difference Vegetation Index(NDVI) Vegetation cover Ecological environment Land use and land cover(LULC) Urban expansion Al-Ahsa Oasis

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Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance

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Chinese Journal of Chemical Engineering 2024年第4期68卷 241-252页

作者： Yunyu Guo Yiran Wang Shu Zhang Yi Wang Song Hu Jun Xiang walid Nabgan Xun Hu School of Material Science and Engineering University of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China Departament d'Enginyeria Química Universitat Rovira i VirgiliTarragona 43007Spain

Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic ***,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam *** results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic *** converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high *** high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts.

关键词： Steam reforming Acetic acid Ni/biochar catalyst Property of coke Reaction intermediates

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Patellofemoral Outcome after Medial Unicompartmental Knee Replacement: A Retrospective Study of 25 Cases

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Open Journal of Orthopedics 2017年第10期7卷 320-328页

作者： Nader Naouar Hamdi Kaziz Thabet Mouelhi Mohamed Amine Triki walid osmane Mohamed Laziz Ben Ayeche Orthopedics Department Sahloul University Hospital Sousse Tunisia

Introduction: Osteoarthritis and impingement, in patellofemoral compartment after partial arthroplasty, have been rarely reported. The purpose of our study was to evaluate outcome at long-term follow-up. Methods: We have reviewed retrospectively twenty-five unicompartmental arthroplasties. The medial parapatellar approach was used in all cases. Patients have been evaluated with regard to patellar impingement and osteoarthritic changes revealed by radiographs. The mean follow-up was 10.4 years. The clinical scoring system of the Knee Society and specific questions regarding patellofemoral symptoms were used for functional outcome. Patellofemoral complications such as osteoarthritis, impingement and the position of the femoral component were diagnosed on X-ray views of the knee. Results: At the final follow-up, fifteen knees revealed lateral patellofemoral osteoarthritis and four knees had patellofemoral impingement. Excepted of two cases, all knees with patella impingement did not revealed degenerative modifications. Anterior pain of the knee was noted more frequently in knees with patellar complications. Patellar impingement was considered the first cause of knee pain, more than knees with degenerative modifications. Only one revision surgery was indicated in front of patellofemoral conflict. The occurrence of patellar impingement depends on the surgical procedure. The anterior position of the femoral component seems to increase the frequency of such complication. Conclusion: Several degenerative modifications may occur in the patello-femoral compartment following partial knee arthroplasty. Patellar impingement and total knee arthritis are the most reported modifications. Functional outcome may be affected progressively when these changes become obvious. Patellar impingement is the major cause of knee pain and needs revision.

关键词： Patellofemoral Unicompartimental Arthroplasty Outcome

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Comparison of QT Correction Methods in the Pediatric Population of a Community Hospital: A Retrospective Study

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Congenital Heart Disease 2024年第1期19卷 107-121页

作者： Koren Hyogene Kwag Ibrahim Kak Ying Li walid Khass Alec McKechnie Oksana Nulman Brande Brown Manoj Chhabra Department of Pediatrics New York Presbyterian Brooklyn Methodist HospitalBrooklyn11215USA Department of Population Health Sciences Division of BiostatisticsWeill Cornell MedicineNew York10065USA

Objective:Accurate measurement of QT interval,the ventricular action potential from depolarization to repolarization,is important for the early detection of Long QT *** most effective QT correction(QTc)formula has yet to be determined in the pediatric population,although it has intrinsically greater extremes in heart rate(HR)and is more susceptible to errors in *** authors of this study compare six dif-ferent QTc methods(Bazett,Fridericia,Framingham,Hodges,Rautaharju,and a computer algorithm utilizing the Bazett formula)for consistency against variations in HR and RR ***:Descriptive Retrospective *** included participants from a pediatric cardiology practice of a community hospital who had an ECG performed in *** participants were healthy patients with no past medical history and no regular ***:ECGs from 95 participants from one month to 21 years of age(mean 9.7 years)were included with a mean HR of 91 beats per minute(bpm).The two-sample paired t-test or Wilcoxon signed-rank test assessed for any difference between QTc methods.A statistically signiﬁcant difference was observed between every combination of two QTc *** Spearman’s rank correlation analysis explored the QTc/HR and QTc/RR relationships for each *** method was most independent of HR and RR with the lowest absolute value of correlation coefﬁ*** and Computer had moderate correlations,while Framingham and Rautaharju exhibited strong *** were positive for Bazett and Computer,reﬂecting results from prior studies demonstrating an over-correction of Bazett at higher *** the linear QTc/HR regression analysis,Bazett had the slope closest to zero,although Computer,Hodges,and Fridericia had comparable ***,Fridericia had the linear QTc/RR regression coefﬁcient closest to *** Bland-Altman method assessed for bias and the limits of agreement between correction *** an

关键词： Corrected QT interval QT prolongation long QT syndrome electrocardiogram retrospective study bazett fridericia framingham hodges rautaharju computer algorithm

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Soil erosion susceptibility mapping of Hangu Region,Kohat Plateau of Pakistan using GIS and RS-based models

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Journal of Mountain Science 2024年第8期21卷 2547-2561页

作者： Fakhrul ISLAM Liaqat Ali WASEEM Tehmina BIBI Waqar AHMAD Muhammad SADIQ Matee ULLAH walid SOUFAN Aqil TARIQ Department of Geology Khushal Khan Khattak UniversityKarak 27200Pakistan Department of Geography Government College University FaisalabadPunjab 38000Pakistan Institute of Geology The University of Azad Jammu&KashmirMuzaffarabad 13100Pakistan Department of Earth Sciences Changan UniversityXi’an 710003China NCEG University of PeshawarPeshawar 25120Pakistan Faculty of Earth Sciences Geography and AstronomyUniversity of ViennaVienna 1090Austria Plant Production Department College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Wildlife Fisheries and AquacultureCollege of Forest ResourcesMississippi State UniversityMS 39762USA

Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and ***,this study uses geospatial modeling to produce soil erosion susceptibility maps(SESM)for the Hangu region,Khyber Pakhtunkhwa(KPK),*** Hangu region,located in the Kohat Plateau of KPK,Pakistan,is particularly susceptible to soil erosion due to its unique geomorphological and climatic ***,the Hangu region is characterized by a combination of steep slopes,variable rainfall patterns,diverse land use,and distinct soil types,all of which contribute to the complexity and severity of soil erosion *** factors necessitate a detailed and region-specific study to develop effective soil conservation *** this research,we detected and mapped 1013 soil erosion points and prepared 12 predisposing factors(elevation,aspect,slope,Normalized Differentiate Vegetation Index(NDVI),drainage network,curvature,Land Use Land Cover(LULC),rainfall,lithology,contour,soil texture,and road network)of soil erosion using GIS ***,GIS-based statistical models like the weight of evidence(WOE)and frequency ratio(FR)were applied to produce the SESM for the study *** SESM was reclassified into four classes,i.e.,low,medium,high,and very high *** results of WOE for SESM show that 16.39%,33.02%,29.27%,and 21.30%of areas are covered by low,medium,high,and very high zones,*** contrast,the FR results revealed that 16.50%,24.33%,35.55%,and 23.59%of the areas are occupied by low,medium,high,and very high ***,the reliability of applied models was evaluated using the Area Under Curve(AUC)*** validation results utilizing the area under curve showed that the success rate curve(SRC)and predicted rate curve(PRC)for WOE are 82%and 86%,respectively,while SRC and PRC for FR are 85%and 96%,res

关键词： Soil erosion Geospatial technology Statistical models Hangu Pakistan

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A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa F.Soliman Fatma E.Fadl-Allah walid El-Shafai Mahmoud I.Aly Maali Alabdulhafith Fathi E.Abd El-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier Frequency Division Multiple Access(SC-FDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-FDMA systemas an adopted communication *** introduces a robust image communication framework over SC-FDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-FDMA *** linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-FDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

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Does the Redshift Distribution of Swift Long GRBs Trace the Star-Formation Rate?

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International Journal of Astronomy and Astrophysics 2024年第1期14卷 20-44页

作者： Ali M. Hasan walid J. Azzam Department of Physics College of Science University of Bahrain Sakhir Bahrain

Gamma-ray bursts (GRBs) are extremely powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the time interval during which 90% of the fluence is detected. LGRBs are believed to emanate from the core-collapse of massive stars, while SGRBs are believed to result from the merging of two compact objects, like two neutron stars. Because LGRBs are produced by the violent death of massive stars, we expect that their redshift distribution should trace the star-formation rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sample of 370 LGRBs taken from the Swift catalog, and we investigate different models for the LGRB redshift distribution. We also carry out Monte Carlo simulations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term to fit the distribution well at low redshift.

关键词： Gamma-Ray Bursts Redshift Distribution Star-Formation Rate

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Effect of Single- versus Double-Layer Uterine Closure during Caesarean Section on Niche Formation and Menstrual Irregularity

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Open Journal of Obstetrics and Gynecology 2024年第1期14卷 57-68页

作者： Mohamed Samy Esraa Hussein Fouad Ghoneimy walid Hitler Department of Obstetrics and Gynaecology Faculty of Medicine Ain Shams University Cairo Egypt

Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer one. It may lessen the formation of a niche that is the myometrium’s disruption at the location of the scar of the uterus. Gynecological manifestations, obstetric problems in a future pregnancy and birth, and maybe subfertility are linked to thin RMT and a niche. Objective: To ascertain if double-layer unlocked closure of the uterus is better than single-layer one in terms of post-menstrual spotting and niche development following a first CS. Patients and Methods: In this randomized clinical study, 287 patients were evaluated for qualifying. Of all eligible individuals, 57 patients were excluded from the study based on the inclusion criteria. Results: The variation in ages, gestational age, body mass index (BMI), and cesarean section indications between the two assigned groups is statistically insignificant. However, postmenstrual spotting was statistically significantly more common in single-layer group compared to in double-group. The current study revealed ultrasound findings suggestive of niche formation was statistically significantly more common in single-layer group compared to in double-layer group. Conclusion: As evident from the current study, it demonstrates the advantages of double-layer unlocked closure of the uterus over single-layer one in terms of post-menstrual spotting and niche development following first-time cs. Thus, we deduced that fewer niches are formed, and fewer menstrual spotting occurs in the presence of double unlocked layers closure. To ascertain the impact of uterus closure method on post-operative niche development and the risk of obstetrics and gynaecological problems, further prospective trials with extended follow-up periods are required.

关键词： Single-Layer Double Caesarean Section Residual Myometrium Thickness

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Tribological and Physicochemical Analysis of Squid Pen High-density Polyethylene Biocomposite for Medical Application

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Journal of Bionic Engineering 2022年第5期19卷 1481-1492页

作者： Besma Sidia walid Bensalah Mechanical Engineering Laboratory LR99ES32National Engineering School of MonastirUniversity of MonastirMonastirTunisia

High-Density Polyethylene(HDPE)wear debris generated in the hip joint prothesis leads to its *** aim of this study was to evaluate the potential of Squid Pen(SP)on the tribological and physicochemical properties of HDPE *** filled with 0,5,10,15 and 20 wt.%SP were elaborated by hot compression *** tests were carried out using a reciprocating pin-on-disc *** hardness,Fourier-Transform infra-red(FTIR)analysis,Scanning Electron Microscopy(SEM)of the biocomposite were *** analysis results of the biocomposites showed that an increase in the crystallinity rate was obtained with the addition of SP *** 10 wt.%of SP has a significant effect on the hardness of the *** correlation between the friction coefficient and the wear resistance of the composite was *** 5 wt.%SP-HDPE biocomposite has the lowest friction coefficient value with a decrease in the specific wear rate,compared to the unfilled *** SEM results showed that SP wear debris played an important role as a third roller body at the interface reducing the friction coefficient of the *** was concluded that the HDPE biocomposite could be successfully reinforced with 5 wt.%of SP.

关键词： Squid pen biomaterial Tribological behaviours FTIR analysis Wear morphology Bionic

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基于ABAQUS的积水路面轮胎滑水性能研究

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江苏理工学院学报 2024年第2期30卷 93-105页

作者：过锦飞李波贝绍轶张兰春胡少峰 walid Daoud 胡梦丹江苏理工学院汽车与交通工程学院江苏常州213001 清华大学苏州汽车研究院江苏苏州215131 北汽重型汽车有限公司江苏常州213003 香港城市大学材料工程与科学学院中国香港999007

随着道路交通网络的不断发展,行车安全已经成为当今社会关注的焦点之一。特别是在恶劣天气条件下,如:雨天,车辆在积水路面上高速行驶时,由于动水升力的存在,很容易出现“滑水”现象,从而导致事故的发生。文章深入分析了轮胎在积水路面... 详细信息

随着道路交通网络的不断发展,行车安全已经成为当今社会关注的焦点之一。特别是在恶劣天气条件下,如:雨天,车辆在积水路面上高速行驶时,由于动水升力的存在,很容易出现“滑水”现象,从而导致事故的发生。文章深入分析了轮胎在积水路面上的滑水性能,以提高车辆的行驶稳定性和安全性。首先,使用ABAQUS建立205/55R16子午线轮胎有限元模型,并且对其进行了静力学分析。接着,基于流固耦合方法,构建了一个包含轮胎、水层和路面的复杂耦合模型。在这个模型中,考虑了轮胎充气压力、水层厚度、轮胎垂向负载以及胎面磨损4个关键因素。有限元模拟分析结果表明,轮胎充气压力和垂向载荷的增大都会导致车辆在积水道路上的极限滑水速度增大;相反,胎面磨损和水层厚度的增大,则会导致车辆在积水道路上的极限滑水速度减小。其中,充气压力对滑水性能影响较大,相同条件下,车辆的极限滑水速度从1.7 bar下的72.43 km/h上升到了2.9 bar下的102.23 km/h。所以,雨天适当增大轮胎充气压力更有利于车辆行驶安全。

关键词： ABAQUS 轮胎有限元流固耦合轮胎滑水

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