Kuwait Journal of Science最新文献_第3页

Study on the relationship between topological characteristics of vegetation ecospatial network and sand fixation function in the Mongolian Plateau 蒙古高原植被生态空间网络拓扑特征与固沙功能关系研究

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-04-11 DOI: 10.1016/j.kjs.2025.100411

Jie Zang , Qian Li , Qiang Yu , Avirmed Buyanbaatar , Qibin Zhang , Yueyue Wang , Hongli Song

{"title":"Study on the relationship between topological characteristics of vegetation ecospatial network and sand fixation function in the Mongolian Plateau","authors":"Jie Zang , Qian Li , Qiang Yu , Avirmed Buyanbaatar , Qibin Zhang , Yueyue Wang , Hongli Song","doi":"10.1016/j.kjs.2025.100411","DOIUrl":"10.1016/j.kjs.2025.100411","url":null,"abstract":"<div><div>The spatial structure of vegetation plays a pivotal role in determining the sand fixation function of ecosystems. However, the interaction between vegetation spatial structure at the regional scale and its sand fixation function remains insufficiently understood. Addressing this gap is essential for developing effective strategies to mitigate soil erosion, combat desertification, and enhance ecosystem stability in arid and semi-arid regions. This study investigates the Mongolian Plateau, a region highly vulnerable to wind erosion. Using the minimum cumulative resistance (MCR) model and complex network theory, the regional-scale vegetation structure was abstracted into a vegetation ecospatial network (VEN), and its topological characteristics were analyzed. The revised wind erosion equation (RWEQ) was then applied to estimate soil wind erosion and evaluate vegetation's sand fixation function for 2020. Correlation analysis was conducted to explore the relationships between VEN topological indicators, vegetation-driven sand fixation, and regional wind erosion. The results revealed the 2020 Mongolian Plateau VEN as a scale-free small-world network with strong heterogeneity. Wind erosion modulus of the Mongolian Plateau in 2020 amounted to 33.79 t hm<sup>−2</sup>, while vegetation sand fixation amount reached 48.68 t hm<sup>−2</sup>. Most VEN nodes exhibited high sand fixation function. Node sand fixation function exhibited a strong positive correlation with PageRank and a substantial positive correlation with degree and betweenness centrality. These findings can provide insights into optimizing vegetation patterns and enhancing sand fixation function.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100411"},"PeriodicalIF":1.2,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of surface deformation patterns using InSAR data: Implications for human impacts in Makkah City, Saudi Arabia 利用InSAR数据评估地表变形模式：对沙特阿拉伯麦加市人类影响的影响

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-04-09 DOI: 10.1016/j.kjs.2025.100419

Mohamed Elhag , Anis Chaabani , Lifu Zhang

{"title":"Assessment of surface deformation patterns using InSAR data: Implications for human impacts in Makkah City, Saudi Arabia","authors":"Mohamed Elhag , Anis Chaabani , Lifu Zhang","doi":"10.1016/j.kjs.2025.100419","DOIUrl":"10.1016/j.kjs.2025.100419","url":null,"abstract":"<div><div>Makkah City is undergoing extensive urban development to accommodate the growing number of Hajj pilgrims. This study applied Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) to map ground surface deformation in Makkah using a time series of 166 Sentinel-1 radar images acquired between December 2017 and January 2021. PS-InSAR enables the measurement of tiny displacements over time using phase differences between SAR images. A total of 85,484 persistent scatterers were identified, and their line-of-sight deformation velocities were estimated. The results show that deformation rates in Makkah City ranged from −19.1 to +19.1 mm/year during the study period, with positive velocities indicating movement away from the radar (ground swelling) and negative velocities representing motion towards the radar (subsidence). Spatial patterns of deformation correlated well with ongoing construction projects such as tunneling, infrastructure development, and groundwater extraction. This study demonstrates the capability of PS-InSAR for detailed and high-precision monitoring of urban ground motions caused by human activities in highly sensitive regions like Makkah. Continuous deformation monitoring is important for ensuring the safety and preservation of cultural heritage in the holy city.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100419"},"PeriodicalIF":1.2,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tunable domain wall pinning behavior by notch geometry in CoFeB nanostrip under nano-pulse current injection 纳米脉冲电流注入下CoFeB纳米带的缺口几何可调畴壁钉钉行为

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-04-07 DOI: 10.1016/j.kjs.2025.100418

Candra Kurniawan , Raditya Nugraha , Dong-Hyun Kim , Dede Djuhana

{"title":"Tunable domain wall pinning behavior by notch geometry in CoFeB nanostrip under nano-pulse current injection","authors":"Candra Kurniawan , Raditya Nugraha , Dong-Hyun Kim , Dede Djuhana","doi":"10.1016/j.kjs.2025.100418","DOIUrl":"10.1016/j.kjs.2025.100418","url":null,"abstract":"<div><div>To optimally control the domain wall (DW) pinning behavior in the ferromagnetic nanostrip, some focus is on utilizing a geometrical notch as an artificial pinning potential. Most of the studies were intended to explain the dynamics of DW structure when it passes or moves out from the notch. However, there is still a lack of discussion about the effect of the geometrical structure of notches in the nanostrips. This work investigated the effect of notch geometry on the domain wall tunability pinning behavior under nanosecond pulse current injection using micromagnetic simulation from its initial ground-state condition. The micromagnetic model of the material mimicked the perpendicular magnetization of the CoFeB stripe-shaped nanowire with a perfect single crystalline structure. The DW depinning condition determined by the edge of DW leaves out the notch area, which was related to the minimum energy needed to surpass the artificial pinning potential in the nanostrip made by the notch. The micromagnetic results showed that the notch depth variation linearly increased the depinning current density value. Moreover, the depinning current value was significantly increasing on the smaller nanostrip slit analog to the larger notch depth above 20 nm. In this case, the medium size of nanostrip geometries and notch sizes are considerable for the effective DW pinning and control in the CoFeB nanostrip.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100418"},"PeriodicalIF":1.2,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simple synthesis of reduced graphene oxide (rGO) from lignite via controlled carbonization temperature for energy storage electrodes 通过控制碳化温度从褐煤中简单合成用于储能电极的还原氧化石墨烯 (rGO)

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-04-05 DOI: 10.1016/j.kjs.2025.100417

Wiwin Dwiana , Rini Zaqiyah , Erma Surya Yuliana , Silvi Rahmawati Wibowo , Muchammad Harly , Sunaryono Sunaryono , Tahta Amrillah , Muhammad Aziz , Nandang Mufti

{"title":"Simple synthesis of reduced graphene oxide (rGO) from lignite via controlled carbonization temperature for energy storage electrodes","authors":"Wiwin Dwiana , Rini Zaqiyah , Erma Surya Yuliana , Silvi Rahmawati Wibowo , Muchammad Harly , Sunaryono Sunaryono , Tahta Amrillah , Muhammad Aziz , Nandang Mufti","doi":"10.1016/j.kjs.2025.100417","DOIUrl":"10.1016/j.kjs.2025.100417","url":null,"abstract":"<div><div>Lignite coal was carbonized at 400 °C, 500 °C, and 600 °C to produce coalite samples, subsequently synthesized into reduced graphene oxide (rGO) using Hummer's method. The synthesized rGO was then fabricated as an electrode. This study examines how coalite carbonization temperature affects rGO synthesis as a sodium ion battery (SIB) cathode. Characterization results confirmed successful synthesis: X-ray diffraction (XRD) showed an amorphous structure with a 25° peak, Fourier Transform Infrared Spectroscopy (FTIR) identified key functional groups, and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) mapping recorded the highest porosity (69.19 %) in the rGO 600 sample. Electrochemical tests (galvanostatic charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy) demonstrated superior performance in the rGO 600 sample, achieving a specific capacity of 17.85 F/g, a power density of 41.82 W/kg, and an energy density of 0.197 Wh/kg. These results indicate a positive correlation between rGO porosity and electrochemical performance, supporting rGO from coalite as a promising material for future sustainable supercapacitors.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100417"},"PeriodicalIF":1.2,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An application of modified systematic sampling in auto-correlated populations 改良系统抽样在自相关人群中的应用

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-31 DOI: 10.1016/j.kjs.2025.100404

Zaheen Khan , Laila A. Al-Essa , Fuad S. Al Duais , Javid Shabbir , Sat Gupta

引用次数: 0

Green synthesis and characterisation of silver nanoparticles (AgNPs) from Rubus sanctus schreber leaf aqueous extract and evaluation of their antibacterial and cytotoxic activities 山楂叶水提物纳米银的绿色合成、表征及其抗菌和细胞毒活性评价

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-28 DOI: 10.1016/j.kjs.2025.100416

Hülya Hoşgören

{"title":"Green synthesis and characterisation of silver nanoparticles (AgNPs) from Rubus sanctus schreber leaf aqueous extract and evaluation of their antibacterial and cytotoxic activities","authors":"Hülya Hoşgören","doi":"10.1016/j.kjs.2025.100416","DOIUrl":"10.1016/j.kjs.2025.100416","url":null,"abstract":"<div><div>The current study optimised the numerous experimental parameters required for the generation and stability of silver nanoparticles (AgNPs) by the green synthesis of AgNP utilizing aqueous <em>Rubus sanctus</em> leaf extract. By employing UV–visible analysis to find the surface plasmon resonance band at 436.5 nm, the creation of nanoparticles was verified. Based on the Fourier transform infrared spectroscopy (FT-IR), the phytochemical components present in the leaf extract of <em>Rubus sanctus</em> significantly impacted the synthesis of AgNPs as a bio-reducing agent. The shape, size, and elemental composition of AgNPs were examined using X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscope (SEM), and transmission electron microscope (TEM), and the results showed that the particles were crystalline, spherical silver nanoparticles. Additionally, AgNPs' inhibitory effects on the growth of pathogenic <em>Staphylococcus aureus</em>, <em>Bacillus subtilis</em>, <em>Escherichia coli</em>, <em>Pseudomonas aeruginosa</em> bacteria, and <em>Candida albicans</em> yeast were evaluated using the microdilution technique. The results showed that nanoparticles worked even at low concentrations. To test the cytotoxicity of biosynthesised AgNPs, three cancer cell lines, the prostate (LnCap), breast (MDA-MB231), and colon (Caco2), as well as a healthy human embryonic kidney (HEK293) cell line, were used. At high dosages, it was observed that <em>Rubus sanctus</em>-AgNPs had potent cytotoxic activity on the cancer cell lines LnCap, MDA-MB231, and Caco2, but their cytotoxicity was less on the control HEK293 cell line. From the data, it can be inferred that biogenic AgNPs were functionalised, and these compounds demonstrated significant potential as antibacterial and anti-cancer agents for industrial and medical applications.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100416"},"PeriodicalIF":1.2,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143817592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Turning waste into value: Banana peel biochar particle electrode boost methyl violet 2B dye removal in 3D-electrochemical system 变废为利：香蕉皮生物炭颗粒电极在3d -电化学系统中促进甲基紫2B染料的去除

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-27 DOI: 10.1016/j.kjs.2025.100413

Syed Madhi Haider Kazmi , Jiangkun Du , Atya Hassan , Zhao Xu , Muhammad Faheem , Owais Ahmed Waseem , Muhammad Yousuf

{"title":"Turning waste into value: Banana peel biochar particle electrode boost methyl violet 2B dye removal in 3D-electrochemical system","authors":"Syed Madhi Haider Kazmi , Jiangkun Du , Atya Hassan , Zhao Xu , Muhammad Faheem , Owais Ahmed Waseem , Muhammad Yousuf","doi":"10.1016/j.kjs.2025.100413","DOIUrl":"10.1016/j.kjs.2025.100413","url":null,"abstract":"<div><div>Water-soluble cationic dyes pose significant risks to human health and aquatic ecosystems. However, conventional adsorbents and removal techniques are ineffective in eliminating them from wastewater. To address this challenging issue, we synthesized banana peel biochar (BPB) and unveiled its role as a particle electrode for the removal of carcinogenic methyl violet 2B dye (MV 2B) in a cutting-edge three-dimensional electrochemical system with the use of titanium (Ti) anode and graphite (GP) cathode (BPB–Ti/GP). Catalytic features of the BPB were explored and its electrochemical characteristics were studied through linear sweep voltammetry and cyclic voltammetry revealed a high oxygen evolution potential (OEP) of 1.86 V. High OEP of BPB particle electrode induced the MV 2B dye oxidation by reducing the oxygen evolution side reaction (OER) of the electrochemical system. At optimum operating conditions of the current density (<em>j</em>) of 5.2 mA/cm<sup>2</sup>, pH 9.0, and Na<sub>2</sub>SO<sub>4</sub> dose of 0.2 M, nearly 99.50 % of 10 mg/L MV 2B dye removal was attained in 40 min of electrolysis time. Compared to the BPB-Ti/GP system, the system with commercial particle electrodes (GAC, MnO<sub>2</sub>, and Fe<sub>3</sub>O<sub>4</sub>) showed no significant performance. Energy consumption and electrical energy per order of BPB-Ti/GP system was also calculated. Furthermore, hydroxyl radical (<sup>•</sup>OH) was identified as the dominant reactive oxygen species. Moreover, liquid chromatography-mass spectroscopy analysis showed that MV 2B underwent degradation through N-demethylation. This unique approach does not only reduce agricultural waste but also induce the sustainability of wastewater treatment processes, paving the way for greener environmental solutions.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100413"},"PeriodicalIF":1.2,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrophilic vs. amphiphilic anionic Zn(II) phthalocyanines for photodynamic therapy 亲水与两亲性阴离子锌（II）酞菁用于光动力治疗

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-27 DOI: 10.1016/j.kjs.2025.100415

Nouf S. Al-Hamdan , Ethar S. Makhseed , Ali Husain , Efkan Bağda , Esra Bağda , Didem Duman , Ebubekir Ayhan , Asaithampi Ganesan , Mahmut Durmuş , Saad Makhseed

{"title":"Hydrophilic vs. amphiphilic anionic Zn(II) phthalocyanines for photodynamic therapy","authors":"Nouf S. Al-Hamdan , Ethar S. Makhseed , Ali Husain , Efkan Bağda , Esra Bağda , Didem Duman , Ebubekir Ayhan , Asaithampi Ganesan , Mahmut Durmuş , Saad Makhseed","doi":"10.1016/j.kjs.2025.100415","DOIUrl":"10.1016/j.kjs.2025.100415","url":null,"abstract":"<div><div>Two sets of water-soluble zinc (II) phthalocyanines (Zn[II]Pcs) were synthesized and examined for use as photosensitizers in photodynamic therapy. These Zn(II)Pcs contained numerous negatively charged electron-withdrawing carboxylic acid substituents in a rigid arrangement at peripheral positions, subsequently converted into sodium salts. Additionally, the impact of the number and distribution of charged groups on the planar hydrophobic core was examined to assess their influence on the photophysical properties and self-aggregation behavior of the Pcs in an aqueous media. The photophysical findings indicate that the amphiphilic macrocycles (<strong>2A</strong>, <strong>3A</strong>, and <strong>4A</strong>) produce more singlet oxygen than the hydrophilic ones (<strong>2H</strong>, <strong>3H</strong>, and <strong>4H</strong>) in DMF. The photodynamic activity of sodium salts of Zn(II)Pcs bearing anionic substituents (compounds <strong>4A</strong> and <strong>4H</strong>) was evaluated <em>in vitro</em> against oral squamous cell carcinoma (SCC-9) and mouse fibroblast (L-929) cell lines to help elucidate the cell death mechanism. The results confirmed that <strong>4A</strong> exhibits high selectivity and efficiency in causing phototoxicity, with an IC<sub>50</sub> value of around 3.8 μM. This work provides new insights into the advanced development of dual-directional ZnPc-based photodynamic therapy agents for treating oral squamous cell cancer.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100415"},"PeriodicalIF":1.2,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Environmental implications of geohazard analysis in a climatically variable arid region: A case study of the Al-Mutla’a-Al-Jahra Coastal Plain, State of Kuwait 气候变化干旱地区地质灾害分析的环境影响：以科威特Al-Mutla 'a-Al-Jahra沿海平原为例

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-27 DOI: 10.1016/j.kjs.2025.100414

Esraa S. Bu Hamad , Mohamed I. El Anbaawy , Faisal A.N. AlSharifi , Mohamed S. Hammed , Ahmed Abdelhalim

{"title":"Environmental implications of geohazard analysis in a climatically variable arid region: A case study of the Al-Mutla’a-Al-Jahra Coastal Plain, State of Kuwait","authors":"Esraa S. Bu Hamad , Mohamed I. El Anbaawy , Faisal A.N. AlSharifi , Mohamed S. Hammed , Ahmed Abdelhalim","doi":"10.1016/j.kjs.2025.100414","DOIUrl":"10.1016/j.kjs.2025.100414","url":null,"abstract":"<div><div>This study addresses the pressing need for integrated environmental management in Kuwait's central coastal arid zone, which faces increasing environmental challenges due to extensive human activities and climate change. The research employs remote sensing (RS), geographic information systems (GIS), land use and land cover (LU/LC) change detection, watershed analysis, and fieldwork to assess both regional paleo-drainage systems and local basins. The findings identify Al-Jahra and Al-Mutlla'a as areas highly susceptible to flash flooding and Al-Mutlla'a to sand encroachment. Morphometric analysis indicates that regional basins such as B2, B3, and B4 exhibit moderate drainage densities (0.37–4.9) and elongated shapes, which mitigate flash flood risks. In contrast, local basins like Jal-Az-Zor and Jal-Al-Atraf have higher drainage densities (1.9–2.4), steep slopes (>45°), and elevated relief ratios (19.13–20.4), making them more vulnerable to flash floods and erosion. Urbanization analysis reveals a 33.7 % expansion in urban areas between 1986 and 2021, with a notable acceleration from 2013 to 2021 at a rate of 10 km<sup>2</sup> per year. Additionally, sand movement and land-use changes have heightened landscape instability, particularly in inland desert dune fields, which remain highly dynamic. The findings highlight the need for tailored land management policies, including proposed trenching projects around Al-Jahra and integrated environmental management plans to enhance resilience against these hazards and support sustainable development.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100414"},"PeriodicalIF":1.2,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bagging-based heteroscedasticity-adjusted ridge estimators in the linear regression model 线性回归模型中基于bagging的异方差调整脊估计

IF 1.2 4区综合性期刊

Kuwait Journal of Science Pub Date : 2025-03-26 DOI: 10.1016/j.kjs.2025.100412

Maha Shabbir , Sohail Chand , Irum Sajjad Dar

{"title":"Bagging-based heteroscedasticity-adjusted ridge estimators in the linear regression model","authors":"Maha Shabbir , Sohail Chand , Irum Sajjad Dar","doi":"10.1016/j.kjs.2025.100412","DOIUrl":"10.1016/j.kjs.2025.100412","url":null,"abstract":"<div><div>The existence of multicollinearity between independent variables and heteroscedastic error has a colossal impact on the performance of the ordinary least square (OLS) estimator and its covariance matrix. In this study, new bootstrap aggregation (i.e. bagging) based ridge estimators are introduced to circumvent multicollinearity by controlling the influence of heteroscedastic error terms. These estimators are a novel combination of bagging and heteroscedastic-adjusted ridge (HAR) estimators. The performance of bagging-based HAR estimators is evaluated using intensive Monte Carlo simulations by considering multicollinearity with low, high, and severe degrees of heteroscedasticity. The findings reveal that at severe heteroscedasticity, the performance of the proposed HAR-HK∗, HAR-LW∗, HAR-HSL∗, and HAR-KMS∗ estimators is 26.3 %, 81.5 %, 90.1 %, and 30.5 % better than their HAR-HK, HAR-LW, HAR-HSL, and HAR-KMS counterparts when the collinearity level is 0.80, sample size is 25, and the number of independent variables is 5. Similar improvements are observed when heteroscedasticity levels are low and moderate, with different specifications for sample size, collinearity level, and number of independent variables. Overall, the bagging-based HAR estimators are efficient and perform better than the baseline HAR estimators. The real-life applications are illustrated using livestock and passenger car mileage data. The outcomes show that the suggested HAR-LW∗ (PRESS = 10.5028) and HAR-KMS∗(PRESS = 0.0497) perform best on the passenger car and livestock data respectively. The improvements will be helpful in efficiently handling the estimation problem when the two challenging issues are present in the data.</div></div>","PeriodicalId":17848,"journal":{"name":"Kuwait Journal of Science","volume":"52 3","pages":"Article 100412"},"PeriodicalIF":1.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0