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Precise LULC classification of rural area combining elevational and reflectance characteristics using UAV 利用无人机结合高程和反射率特征对农村地区进行精确的土地利用、土地利用变化和土壤侵蚀分类
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-18 DOI: 10.1016/j.sciaf.2024.e02431
Ke Zhang , Lameck Fiwa , Madoka Kurata , Hiromu Okazawa , Kenford A.B. Luweya , Mohammad Shamim Hasan Mandal , Toru Sakai
With the development of unmanned aerial vehicle (UAV) in the recent decade, very high-resolution aerial imagery has been used for precise land use/land cover classification (LULC). However, special structures in rural areas of developing countries such as traditional thatched houses have posed challenges for precise LULC classification due to their undistinctive appearance and confusable characteristics in both reflectance and structure. LULC mapping is essential particularly in rural areas which have high data scarcity and vulnerability to natural disasters. With high-resolution observation has been achieved by UAVs, it is important to propose high-precision LULC classification methods which can fully use the advantages of UAVs. To emphasize the differences among the common LULC types in rural areas, this study proposed an original index, the rural residence classification index (RCI). RCI was calculated as the product of the above ground height and the square of the difference between the NDVI value and one. Then, a comprehensive classification method was established by combining the RCI, the traditional threshold method and a machine learning method. As a result of the comparison with the traditional threshold method, object-based image analysis, and random forest methods, the method by this study achieved the highest overall accuracy (overall accuracy = 0.903, kappa = 0.875) and classification accuracy for detecting thatched houses (user's accuracy = 0.802, producer's accuracy = 0.920). These findings showed the possibility on identifying the confusable structures in rural areas using remote sensing data, which was found difficult by the previous studies so far. The method by this study can promote the further utility of UAVs in LULC classification in rural areas in developing countries, thereby providing precise and reliable material for hydrological, hydraulic or ecosystem modelling, which eventually contributes to more accurate natural hazard risk assessment, rural development, and natural resource management.
近十年来,随着无人飞行器(UAV)的发展,高分辨率航空图像已被用于精确的土地利用/土地覆被分类(LULC)。然而,发展中国家农村地区的特殊结构,如传统茅草房,由于其外观不明显,在反射率和结构方面的特征容易混淆,给精确的土地利用、土地覆被分类带来了挑战。土地利用、土地利用变化和土地利用变化测绘至关重要,尤其是在数据高度稀缺和易受自然灾害影响的农村地区。随着无人机实现了高分辨率观测,提出能充分利用无人机优势的高精度 LULC 分类方法就显得尤为重要。为了强调农村地区常见 LULC 类型之间的差异,本研究提出了一个独创的指标--农村居住地分类指数(RCI)。RCI 的计算方法是地面以上高度与 NDVI 值与 1 之差的平方的乘积。然后,结合 RCI、传统阈值法和机器学习法,建立了一种综合分类方法。通过与传统阈值法、基于对象的图像分析法和随机森林法的比较,本研究的方法在检测茅草房方面取得了最高的总体准确率(总体准确率 = 0.903,kappa = 0.875)和分类准确率(用户准确率 = 0.802,生产者准确率 = 0.920)。这些研究结果表明,利用遥感数据识别农村地区易混淆结构是可行的,而这在以往的研究中是很难做到的。本研究的方法可进一步促进无人机在发展中国家农村地区 LULC 分类中的应用,从而为水文、水力或生态系统建模提供精确可靠的材料,最终有助于更准确地进行自然灾害风险评估、农村发展和自然资源管理。
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引用次数: 0
Surface water quality assessment and probable health threats of metal exposure in the Tano South Municipality, Ahafo, Ghana 加纳阿哈福塔诺南市地表水质量评估和接触金属可能对健康造成的威胁
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-18 DOI: 10.1016/j.sciaf.2024.e02437
Jackson Adiyiah Nyantakyi , Lilian Sarpong , Roland Boadi Mensah , Samuel Wiafe
The prime goal of this study was to assess the surface water quality and the associated health risks for residents in the Tano South Municipality, Ghana. The WHO drinking water criteria were compared with the findings of an analysis of eight surface waters for parameters such as physiochemical parameters, nutrient levels, and concentrations of selected metals. An evaluation was performed regarding the potential non-carcinogenic and carcinogenic risks associated with metal exposure by oral and dermal absorption. The estimated water quality index indicated that seven water samples were deemed unsuitable for human consumption, while one sample indicated very low water quality. The fluoride levels in all water samples were below the limit of detection, although it guards against dental caries. All of the water samples had mean concentrations of Cd and Fe above WHO guideline values, while one water sample had a Pb concentration that was higher than recommended. Principal component analysis showed that aside from the natural source, human-induced sources such as runoff of excess chemicals and soil erosion from adjacent farm soils were responsible for the substantial levels of contaminants in surface water samples. There was a possibility of non-carcinogenic consequences for children in seven out of eight water samples. However, cancer risk for Cd and Pb was not likely for adults and children in the study area. Findings serve as a representative case study for other districts and call on water managers to treat surface waters to guard against harmful health consequences and safeguard the designated buffer zones.
这项研究的主要目的是评估加纳塔诺南市的地表水水质以及与之相关的居民健康风险。将世界卫生组织的饮用水标准与对八种地表水的参数(如理化参数、营养水平和选定金属的浓度)的分析结果进行了比较。对通过口服和皮肤吸收接触金属可能产生的非致癌和致癌风险进行了评估。估计的水质指数表明,有七个水样不适合人类饮用,一个水样的水质极差。尽管氟可以预防龋齿,但所有水样中的氟含量都低于检测限。所有水样中镉和铁的平均浓度都高于世界卫生组织的指导值,而一个水样中铅的浓度高于建议值。主成分分析表明,地表水样本中污染物含量高的原因除自然来源外,还有人为来源,如过量化学品的径流和邻近农场土壤的侵蚀。在 8 个水样中,有 7 个水样可能会对儿童造成非致癌后果。不过,镉和铅对研究地区的成人和儿童都不可能有致癌风险。研究结果可作为其他地区的代表性案例研究,并呼吁水资源管理者对地表水进行处理,以防止有害健康的后果,并保护指定的缓冲区。
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引用次数: 0
Aloe ferox leaf gel extracts attenuate redox imbalance in oxidative renal injury and stimulates glucose uptake, whilst inhibiting key enzymes linked to diabetes and obesity 阿魏芦荟叶凝胶提取物可减轻氧化性肾损伤中的氧化还原失衡,刺激葡萄糖摄取,同时抑制与糖尿病和肥胖症有关的关键酶。
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-17 DOI: 10.1016/j.sciaf.2024.e02425
Huda Ismail, Almahi I. Mohamed, Md. Shahidul Islam
The worldwide prevalence of diabetes and obesity is growing rapidly. Both metabolic disorders are linked to chronic adverse complications, which include kidney dysfunctions. Medicinal plants play a crucial role in traditional healthcare, especially in developing countries. Aloe ferox, native to South Africa, has a long history of medicinal use, but its pharmacological potential is less studied compared to other Aloe species, necessitating further investigation. Therefore, the present study was conducted to determine the antioxidative, anti-obesogenic, and antidiabetic effects of A. ferox leaf gel extracts using in vitro, ex vivo, and in silico experimental models, with oxidative renal damage induced by ferrous sulfate (FeSO4). A. ferox leaf gel extracts exhibited strong antioxidant activity, inhibited carbohydrate and lipid digesting enzymes, and significantly improved glucose uptake in yeast. The aqueous extract demonstrated better antioxidant efficacy, leading to higher reduced glutathione (GSH) level, and superoxide dismutase (SOD) and catalase enzymes activity, along with a concurrent reduction of nitric oxide (NO) and malondialdehyde (MDA) levels. Likewise, the aqueous extract showed more potent in vitro DPPH, NO, and OH• radical scavenging activity with IC50 values of 3.64 ± 0.3 μg/mL, 110.73±0.1 μg/mL, and 331.13 ± 0.7 μg/mL, respectively. The aqueous extract had a better inhibition of the enzyme, α-amylase (IC50 = 25.73±2.5 µg/mL), whilst the ethanolic extract inhibited α-glucosidase (IC50 =663.2 ± 0.3 µg/ml), and pancreatic lipase (IC50 =122.01±5.9 µg/mL) more strongly. Incubation of the extracts with yeast cells stimulated glucose uptake dose dependently, when ethanolic extract (IC50 = 308.01±0.7 µg/mL) showed the better effects compared to the aqueous extract (IC50 = 338.79±7.05 µg/mL). Furthermore, LC-MS analysis led to the identification of many compounds, when chlorogenic acid demonstrated a stronger molecular interaction with the active site amino acids of α-amylase and catalase compared to other compounds. However, Aloin B showed the highest binding affinity with α-glucosidase, when 5-Hydroxyaloin A showed the lowest binding energy with lipase and SOD enzymes. These results suggest the reno-protective effects of A. ferox leaf gel extracts against FeSO4-induced oxidative stress along with its anti-hyperglycaemic activity. Given these observed effects, A. ferox leaf gel could be valuable in developing natural therapies and potential drug development for the management of these disorders. Further studies in animal models and humans are needed to ascertain the results of this study.
全球糖尿病和肥胖症的发病率正在迅速增长。这两种代谢性疾病都与慢性不良并发症有关,其中包括肾功能障碍。药用植物在传统保健中发挥着至关重要的作用,尤其是在发展中国家。铁芦荟(Aloe ferox)原产于南非,具有悠久的药用历史,但与其他芦荟品种相比,对其药理潜力的研究较少,因此有必要进行进一步研究。因此,本研究采用硫酸亚铁(FeSO4)诱导氧化性肾损伤的体外、体内和硅学实验模型,确定铁芦荟叶凝胶提取物的抗氧化、抗致肥和抗糖尿病作用。阿魏叶凝胶提取物具有很强的抗氧化活性,能抑制碳水化合物和脂质消化酶,并能显著提高酵母对葡萄糖的吸收。水提取物具有更好的抗氧化功效,可提高还原型谷胱甘肽(GSH)水平、超氧化物歧化酶(SOD)和过氧化氢酶活性,同时降低一氧化氮(NO)和丙二醛(MDA)水平。同样,水提取物显示出更强的体外 DPPH、NO 和 OH 自由基清除活性,IC50 值分别为 3.64 ± 0.3 μg/mL、110.73±0.1 μg/mL 和 331.13 ± 0.7 μg/mL。水提取物对α-淀粉酶(IC50 = 25.73±2.5 µg/mL)有较好的抑制作用,而乙醇提取物对α-葡萄糖苷酶(IC50 =663.2 ± 0.3 µg/ml)和胰脂肪酶(IC50 =122.01±5.9 µg/mL)的抑制作用更强。将提取物与酵母细胞孵育,可刺激葡萄糖摄取,但与水提取物(IC50 = 338.79±7.05 µg/mL)相比,乙醇提取物(IC50 = 308.01±0.7 µg/mL)的效果更好。此外,LC-MS 分析还鉴定了许多化合物,其中绿原酸与α-淀粉酶和过氧化氢酶的活性位点氨基酸的分子相互作用比其他化合物更强。不过,芦荟素 B 与 α-葡萄糖苷酶的结合亲和力最高,而 5-Hydroxyaloin A 与脂肪酶和 SOD 酶的结合能量最低。这些结果表明,阿魏叶凝胶提取物对硫酸亚铁诱导的氧化应激具有保护作用,同时还具有抗高血糖活性。鉴于这些观察到的效果,阿魏叶凝胶可能对开发天然疗法和潜在药物治疗这些疾病很有价值。要确定这项研究的结果,还需要在动物模型和人体中开展进一步的研究。
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引用次数: 0
An evaluation of single and multi-date Landsat image classifications using random forest algorithm in a semi-arid savanna of Ghana, West Africa 使用随机森林算法对西非加纳半干旱热带稀树草原单日期和多日期陆地卫星图像分类进行评估
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-16 DOI: 10.1016/j.sciaf.2024.e02434
Eric Adjei Lawer
Accurate detection and quantification of land use and land cover (LULC) change is critical for understanding landscape patterns in heterogeneous semi-arid environments. This study investigates the performance of single-date and multi-date Landsat images as well as the relationship between different LULC schemes (simple [2 and 4 classes] and complex [6 and 9 classes]) and the resulting classification accuracy. Specifically, the random forest algorithm was applied to Landsat data comprised of different combinations of image dates (single-date and multi-date) captured in June, October, and December for multiple levels of LULC (scheme) mapping and accuracy evaluations due to its high performance when dealing with large data and heterogeneous landscapes. Results indicated that multi-date images consistently produced higher classification accuracies than single-date images. Significant negative correlations observed between the number of classes in LULC schemes and overall accuracy and kappa coefficient indicate that the more complex the LULC scheme, the lower the accuracy produced. Nevertheless, improvement in overall accuracy was negligible for simple schemes (e.g., ∼1 % for two LULC classes), while it was moderate for complex schemes (∼5 %) when using the best-performing images for multi-date (June-October-December) compared to single-date (October) classifications: however, the improvement was considerable when compared to the least performing single-date image (June, 8–15 %). These varying classification accuracies were due to differences or similarities in spectral responses of target classes in the various LULC schemes applied to the investigated images. Consequently, the resulting differences in the spatial distribution and quantification of LULC classes produced by the different approaches can affect policy and land management decisions, especially if inappropriate image dates are used for LULC mapping. Overall, the findings highlight the reliability of appropriate single-date and multi-date images for mapping LULC change using simple and complex schemes in heterogeneous semi-arid savanna landscapes.
准确检测和量化土地利用和土地覆被变化对于了解异质半干旱环境中的景观模式至关重要。本研究调查了单日期和多日期 Landsat 图像的性能,以及不同 LULC 方案(简单 [2 类和 4 类] 与复杂 [6 类和 9 类] 之间的关系和由此产生的分类准确性。具体来说,由于随机森林算法在处理大量数据和异质地貌时具有很高的性能,因此将其应用于由 6 月、10 月和 12 月拍摄的不同影像日期组合(单日期和多日期)组成的 Landsat 数据,以进行多级 LULC(方案)绘图和准确性评估。结果表明,多日期图像的分类准确率始终高于单日期图像。在 LULC 方案的类别数量与总体准确率和卡帕系数之间观察到显著的负相关,表明 LULC 方案越复杂,产生的准确率就越低。然而,当使用多日期(6 月-10 月-12 月)表现最好的图像与单日期(10 月)分类相比时,简单方案的总体准确率提高微乎其微(例如,两个 LULC 类别的准确率为 1%∼1%),而复杂方案的准确率提高适中(5%∼5%);然而,与表现最差的单日期图像(6 月,8%-15%)相比,复杂方案的准确率提高显著。这些不同的分类精度是由于调查图像所采用的各种 LULC 方案中目标类别的光谱响应存在差异或相似性。因此,不同方法产生的 LULC 等级的空间分布和量化差异可能会影响政策和土地管理决策,尤其是在使用不恰当的图像日期绘制 LULC 地图的情况下。总之,研究结果强调了在异质半干旱热带稀树草原地貌中使用简单和复杂方案绘制 LULC 变化图时,适当的单日期和多日期图像的可靠性。
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引用次数: 0
Modelling and forecasting mobile money customer transaction volumes in rural and semi-urban Malawi: An autoregressive integrated moving average spatial decomposition 马拉维农村和半城市地区移动支付客户交易量的建模和预测:自回归综合移动平均空间分解
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-16 DOI: 10.1016/j.sciaf.2024.e02430
Danny Namakhwa , Betchani Henry Mbuyampungatete Tchereni , Winford Masanjala , Collins Duke Namakhwa , Steven Limbanazo Kuchande , Wisdom Richard Mgomezulu
Mobile money technologies in Malawi have revolutionised banking and monetary transactions across geographical barriers. Prospects of profit have drawn mobile money agents to invest in the business but find it is more profitable when substantial customers subscribe to the cash-in and cash-out facilities of mobile money. Despite the initial success, several challenges have emerged, including regulatory hurdles, network reliability issues, and the need for increased financial literacy among users. The volumes of transactions in the rural areas are observably lower compared to urban areas. This study uses Bvumbwe township in Malawi to model and forecast the discrepancy of mobile money transactions in rural and semi-urban Malawi. The study uses ARIMA modelling to understand the temporal manifestation of mobile money subscription in these localities. Using ARMA (1,1) models decomposed for the semi-urban and rural area, the study finds that the semi-urban area has a disproportionately higher and lasting volume of mobile money transactions compared to the rural area. The study also finds that mobile money transactions are more susceptible to long-lasting effects of external shocks in the rural area compared to the urban area. Intuitively, the day-to-day relationship in the transactions is also stronger in the rural area. These findings highlight the need for tailored policy interventions to enhance mobile money adoption and utilization in different geographical contexts.
马拉维的移动支付技术彻底改变了跨越地理障碍的银行业务和货币交易。盈利的前景吸引了移动支付代理商投资这项业务,但他们发现,当大量客户使用移动支付的存取款功能时,利润会更高。尽管取得了初步成功,但也出现了一些挑战,包括监管障碍、网络可靠性问题,以及需要提高用户的金融知识水平。与城市地区相比,农村地区的交易量明显较低。本研究利用马拉维 Bvumbwe 镇来模拟和预测马拉维农村和半城市地区移动支付交易的差异。研究使用 ARIMA 模型来了解这些地区移动支付订阅的时间表现。通过对半城市和农村地区的 ARMA (1,1) 模型进行分解,研究发现,与农村地区相比,半城市地区的移动支付交易量高得不成比例,而且持续时间更长。研究还发现,与城市地区相比,农村地区的移动支付交易更容易受到外部冲击的长期影响。直观地说,农村地区的交易日常关系也更强。这些发现突出表明,有必要采取有针对性的政策干预措施,以促进移动货币在不同地理环境中的采用和使用。
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引用次数: 0
Deployment of mobile application using a novel CNN model for the detection of COVID-19 thoracic disease 利用新型 CNN 模型部署移动应用程序,以检测 COVID-19 胸部疾病
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-16 DOI: 10.1016/j.sciaf.2024.e02432
Steve Okyere-Gyamfi , Vivian Akoto-Adjepong , Kwabena Adu , Mighty Abra Ayidzoe , Obed Appiah , Peter Appiahene , Patrick Kwabena Mensah , Michael Opoku , Faiza Umar Bawah , Nicodemus Songose Awarayi , Samuel Boateng , Peter Nimbe , Adebayo Felix Adekoya
In January 2021 and January 2022, COVID-19 caused roughly 13,000 and 6,000 deaths respectively per day. In August 2022, 26,000 deaths per day were estimated to be caused by COVID-19, followed by 13,000 deaths per day in February 2024. The timely identification and treatment of malignant diseases can potentially lower the mortality rate. Nonetheless, the use of manual methods for diagnosing these conditions requires a meticulous and comprehensive examination, making it susceptible to errors, burdensome for healthcare professionals, and time-intensive. Hence, the objective of this study is to design and deploy a novel deep-learning model for the detection of COVID-19 thoracic diseases. A Convolutional Neural Network (CNN) with less trainable parameters was implemented. This proposed model was deployed on a mobile device using Android Studio and Flutter for the detection of COVID-19 thoracic diseases. Specificity, accuracy, precision, sensitivity, f1-score, ROC, and PR curves were used to evaluate the model's performance. Moreover, the carbon footprint as well as how responsible the proposed model is according to Responsible AI rules was also assessed. The model's evaluation results show an overall accuracy of 93.27 %, specificity of 97.33 %, precision of 93.75 %, sensitivity of 94.42 %, F1-Score of 94.06 %, ROC rate of 98.0 %, PR rate of 96.8 %. The evaluation of the mobile application shows higher generalizability on the COVID-19 dataset. Also, the overall FACETS Score representing responsible AI is 83 % and the carbon footprint (representing the amount of carbon emission emitted into the environment during model training and testing) of 416.73 g with equivalent tree months of 0.45 was obtained. This application with better performance and a low carbon footprint was deployed using Android Studio and Flutter and can assist physicians in the diagnosis of COVID-19 and related diseases.
2021 年 1 月和 2022 年 1 月,COVID-19 每天分别造成约 13,000 人和 6,000 人死亡。2022 年 8 月,COVID-19 估计每天造成 26,000 人死亡,2024 年 2 月每天造成 13,000 人死亡。及时发现和治疗恶性疾病有可能降低死亡率。然而,使用人工方法诊断这些疾病需要进行细致全面的检查,容易出错,给医护人员带来负担,而且耗费时间。因此,本研究旨在设计和部署一种新型深度学习模型,用于检测 COVID-19 胸部疾病。该模型采用了可训练参数较少的卷积神经网络(CNN)。使用 Android Studio 和 Flutter 在移动设备上部署了该模型,用于检测 COVID-19 胸部疾病。特异性、准确性、精确性、灵敏度、f1 分数、ROC 和 PR 曲线被用来评估模型的性能。此外,还评估了碳足迹以及根据负责任人工智能规则所建议的模型的负责任程度。模型的评估结果显示,总体准确率为 93.27%,特异性为 97.33%,精确度为 93.75%,灵敏度为 94.42%,F1 分数为 94.06%,ROC 率为 98.0%,PR 率为 96.8%。移动应用程序的评估结果表明,COVID-19 数据集具有更高的通用性。此外,代表负责任人工智能的总体 FACETS 分数为 83%,碳足迹(代表模型训练和测试期间向环境排放的碳量)为 416.73 克,等效树月数为 0.45。使用 Android Studio 和 Flutter 部署了这款性能更好、碳足迹更低的应用程序,它可以协助医生诊断 COVID-19 和相关疾病。
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引用次数: 0
Improving the accuracy of honey bee forage class mapping using ensemble learning and multi-source satellite data in Google Earth Engine 利用谷歌地球引擎中的集合学习和多源卫星数据提高蜜蜂饲料等级绘图的准确性
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-15 DOI: 10.1016/j.sciaf.2024.e02415
Filagot Mengistu , Binyam Tesfaw Hailu , Temesgen Alemayehu Abera , Janne Heiskanen , Tadesse Terefe Zeleke , Tino Johansson , Petri Pellikka
In semi-arid agro-pastoral environments of Africa, beekeeping is widely recognized as an important activity to improve and diversify livelihoods. Although the scientific identification of suitable honey bees (Apis mellifera ssps.) forages may guide beekeepers to set up apiaries or to timely move honey bee colonies to exploit bee forage resources available in various landscapes, the characterization and mapping of bee forage classes is challenging. We evaluated how various data sources and classification algorithms in Google Earth Engine (GEE) affect the accuracy of honey bee forage class mapping in a semi-arid region of Ethiopia. Predictors derived from multi-source satellite data, such as high-resolution Planet imagery (P), Sentinel 1 RADAR (S1), Sentinel 2 multispectral (S2), and Shuttle Radar Topographic Mission (SRTM) Digital Elevation Model (DEM) were tested and best predictors were identified using Forward Feature Selection (FFS). Four machine learning algorithms (Gradient Tree Boost (GTB), Random Forest (RF), Classification and Regression Trees (CART), and Support Vector Machine (SVM)), all available in GEE, were compared and ensembled for honey bee forage class mapping. The results show that the highest accuracy is obtained by all four algorithms when combining P, S1, S2, and DEM compared to using predictors from a single data source or any other combinations. GTB had higher overall accuracy (90.9 %) than RF (88.2 %), CART (85.5 %), or SVM (79.9 %). Nonetheless, the highest overall accuracy (94.7 %) was obtained when integrating the four machine learning algorithms in an Ensemble Learning Approach (ELA). Applying ELA improved the classification accuracy by 3.8 %, 6.5 %, 9.2 %, and 14.8 % compared to single learner classification algorithms (i.e., GTB, RF, CART, and SVM, respectively). This study demonstrates an improved classification accuracy for honey bee forage class mapping in tropical rangeland by applying ELA, which can provide a better approach for monitoring and managing bee forage resources.
在非洲半干旱农牧环境中,养蜂被广泛认为是改善生计和使生计多样化的一项重要活动。虽然科学鉴定合适的蜜蜂(Apis mellifera sps.)饲料可以指导养蜂人建立养蜂场或及时转移蜜蜂群落,以利用各种地貌中的蜜蜂饲料资源,但蜜蜂饲料类别的特征描述和绘图却具有挑战性。我们评估了谷歌地球引擎(GEE)中的各种数据源和分类算法如何影响埃塞俄比亚半干旱地区蜜蜂饲料类别绘图的准确性。我们测试了从高分辨率行星图像(P)、哨兵 1 号雷达(S1)、哨兵 2 号多光谱(S2)和航天飞机雷达地形任务(SRTM)数字高程模型(DEM)等多源卫星数据中提取的预测因子,并使用前向特征选择(FFS)确定了最佳预测因子。对 GEE 中的四种机器学习算法(梯度树提升算法 (GTB)、随机森林算法 (RF)、分类和回归树算法 (CART) 以及支持向量机算法 (SVM))进行了比较和组合,以绘制蜜蜂饲草类别图。结果表明,与使用来自单一数据源的预测因子或任何其他组合相比,当组合 P、S1、S2 和 DEM 时,所有四种算法都能获得最高的准确率。GTB 的总体准确率(90.9%)高于 RF(88.2%)、CART(85.5%)或 SVM(79.9%)。然而,将四种机器学习算法集成到一个集合学习方法(ELA)中时,获得了最高的总体准确率(94.7%)。与单一学习器分类算法(即 GTB、RF、CART 和 SVM)相比,采用 ELA 可将分类准确率分别提高 3.8%、6.5%、9.2% 和 14.8%。这项研究表明,应用 ELA 可以提高热带牧场蜜蜂饲草类别绘图的分类精度,从而为蜜蜂饲草资源的监测和管理提供更好的方法。
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引用次数: 0
Assessing shell morphology in freshwater mussels (Mollusca: Bivalvia: Unionidae) from the Maâden River, Tunisia: Insights from geometric morphometrics and shape descriptors 评估突尼斯马登河淡水贻贝(软体动物门:双壳纲:联合科)的贝壳形态:几何形态计量学和形状描述符的启示
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-11 DOI: 10.1016/j.sciaf.2024.e02427
Chiheb Fassatoui , Moez Shaiek , Mohamed Salah Romdhane
Identifying freshwater mussel species within the Unionidae family can be challenging due to systematic confusion. This study investigates shell shapes to identify four sympatric species of freshwater mussels (Potamida littoralis, Unio durieui, U. gibbus, and U. ravoisieri) in the Maâden river (northern Tunisia) using two morphological approaches: global shape descriptors and geometric morphometrics of shell contours. The results revealed significant differences in global shape descriptors among the species. More in-depth analyses showed distinct shape variations, with P. littoralis and U. gibbus significantly differing from U. durieui and U. ravoisieri across most descriptors. Notably, U. durieui and U. ravoisieri exhibited similar shape traits, differing primarily in roundness, characterized by low circularity and high ellipticity. Principal Component Analyses depicted substantial morphological variance, with Procrustes data requiring the first two components to fully elucidate dispersion. Linear Discriminant Analysis revealed effective discrimination among species, with an accuracy rate of over 74 % in classifying individuals into their respective populations across both approaches. Geospatial analyses indicated varying influences of latitude, longitude, and altitude on shell morphology among species. Latitude had noteworthy impacts on P. littoralis, approaching significance for shape descriptors and Procrustes data. Conversely, U. durieui and U. gibbus displayed minimal geographic influence on shell morphology, while U. ravoisieri showed significant variations across these parameters. This study highlights the distinct morphological differences among sympatric mussel species in northern Tunisia, providing valuable insights for conservation efforts, especially for species vulnerable to climate change.
由于系统混淆,识别淡水贻贝科中的淡水贻贝物种具有挑战性。本研究采用两种形态学方法:整体形状描述符和贝壳轮廓的几何形态计量学,对贝壳形状进行研究,以识别马登河(突尼斯北部)的四个同域淡水贻贝物种(Potamida littoralis、Unio durieui、U. gibbus 和 U. ravoisieri)。结果表明,不同物种的总体形状描述指标存在显著差异。更深入的分析表明,在大多数描述指标上,P. littoralis 和 U. gibbus 与 U. durieui 和 U. ravoisieri 的形状差异明显。值得注意的是,U. durieui 和 U. ravoisieri 表现出相似的形状特征,主要在圆度方面存在差异,圆度低,椭圆度高。主成分分析显示了巨大的形态差异,Procrustes 数据需要前两个成分才能完全阐明其分散性。线性判别分析显示了物种之间的有效区分,两种方法将个体归入各自种群的准确率超过 74%。地理空间分析表明,纬度、经度和海拔对不同物种的贝壳形态有不同的影响。纬度对 P. littoralis 有显著影响,在形状描述符和 Procrustes 数据方面接近显著性。相反,U. durieui 和 U. gibbus 对贝壳形态的地理影响很小,而 U. ravoisieri 在这些参数上有显著差异。这项研究强调了突尼斯北部同域贻贝物种之间明显的形态差异,为保护工作,尤其是保护易受气候变化影响的物种提供了有价值的见解。
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引用次数: 0
Seasonal changes in the abundance and distribution of large terrestrial mammals in old Oyo National Park, Nigeria 尼日利亚老奥约国家公园大型陆生哺乳动物数量和分布的季节性变化
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-11 DOI: 10.1016/j.sciaf.2024.e02428
Umar Lawal Mohammed , Shahrul Anuar Mohd Sah
Seasonal distribution of large terrestrial mammals in African protected areas is shaped by factors such as food and water availability, breeding cycles, and predation risks. This study utilised encounter rates derived from diurnal distance sampling to examine seasonal variations in the abundance and distribution of these mammals within Old Oyo National Park, Nigeria. Notably, the abundance and distribution in the Marguba range, characterised by mixed open savanna woodland, differed significantly between the dry and wet seasons, as well as among various sub-habitats and ranges during the dry season. The impact of key factors—(1) resource availability (food and water) and/or (2) poaching threat—remains critical and potentially influential in driving these seasonal differences. Further investigation to ascertain the effect of poaching and determine the impact of other controlling factors is crucial. Understanding the effects of these factors is essential for the effective and sustainable management and conservation of large terrestrial mammals in the study area.
非洲保护区内大型陆生哺乳动物的季节性分布受食物和水供应、繁殖周期和捕食风险等因素的影响。本研究利用昼夜距离取样得出的相遇率,研究了这些哺乳动物在尼日利亚老奥约国家公园内的数量和分布的季节性变化。值得注意的是,在以混合开阔稀树草原林地为特征的马格巴分布区,其数量和分布在旱季和雨季之间以及在旱季的各个亚栖息地和分布区之间都存在显著差异。关键因素的影响--(1)资源供应(食物和水)和/或(2)偷猎威胁--仍然至关重要,并可能对这些季节性差异产生影响。进一步调查以确定偷猎的影响并确定其他控制因素的影响至关重要。了解这些因素的影响对于有效、可持续地管理和保护研究地区的大型陆生哺乳动物至关重要。
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引用次数: 0
Optimal sizing of battery energy storage system (BESS) for multiple applications using regression analysis and deep sleep optimizer algorithm 利用回归分析和深度休眠优化算法优化多种应用的电池储能系统(BESS)规模
IF 2.7 Q2 MULTIDISCIPLINARY SCIENCES Pub Date : 2024-10-11 DOI: 10.1016/j.sciaf.2024.e02424
Chukwuemeka Emmanuel Okafor, Komla Agbenyo Folly
The multifunctional applications of battery energy storage system in a power system network will reduce the significant slack time of use as evident in many single-based applications. In order to deploy BESS for multiple applications, it is of utmost importance that the optimal size for the desired multiple functions, firstly be determined. This work proposes a novel methodology for the optimal sizing of battery energy storage system for frequency support, power loss minimization and voltage deviation mitigations. The suggested sizing methodology takes into account the level of penetration of the renewable energy sources in the power network. Regression analysis is used for mathematical formulations while Deep Sleep Heuristic algorithms in MATLAB environment is used for the optimization process for BESS optimal size. The robustness of the proposed method was tested by using IEEE modified 39-bus system. Simulation results show that with the BESS optimal size integrated into the network, voltage deviations were mitigated by about 20 % and power losses were reduced from 65.3 MW to 59.68 MW. Also, the system frequency nadir during the outage of the largest single generating, was sustained at 59.60 Hz whereas, without BESS it was 59.15 Hz. This is critical because such a frequency decline may activate the underfrequency load shedding relays.
电池储能系统在电力系统网络中的多功能应用,将减少许多单一应用中明显存在的大量闲置时间。为了在多种应用中部署 BESS,最重要的是首先确定所需的多种功能的最佳尺寸。这项工作提出了一种新方法,用于优化电池储能系统的大小,以实现频率支持、功率损耗最小化和电压偏差缓解。该方法考虑了可再生能源在电网中的渗透水平。数学公式采用回归分析法,而 BESS 最佳规模的优化过程则采用 MATLAB 环境中的深度睡眠启发式算法。使用 IEEE 修改后的 39 总线系统测试了所提方法的鲁棒性。仿真结果表明,将 BESS 最佳尺寸集成到网络中后,电压偏差减少了约 20%,电力损失从 65.3 MW 降至 59.68 MW。此外,在最大单机停电期间,系统频率最低点维持在 59.60 赫兹,而在没有 BESS 的情况下,系统频率最低点为 59.15 赫兹。这一点至关重要,因为这种频率下降可能会启动欠频甩负荷继电器。
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引用次数: 0
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