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Biodiversity, dynamics, and impact of chakras on the Ecuadorian Amazon

Journal of Plant Ecology 2019年第1期12卷 34-44页

作者： roy r.Vera V J.Hugo Cota-sánchez Jorge E.Grijalva Olmedo University of saskatchewan Department of Biology112 Science PlaceSaskatoon SK S7N 5E2Canada University of saskatchewan Department of Biology and W.P.Fraser Herbarium(SASK)112 Science PlaceSaskatoon SK S7N 5E2Canada Universidad Central del Ecuador Facultad de Medicina Veterinaria y ZootecniaJerónimo Leiton y Gatto SobralQuito 170521Ecuador Estación Experimental santa Catalina Panamericana Sur Km1Instituto Nacional de Investigaciones AgropecuariasMejía 171101Ecuador

Aims Deforestation and biodiversity loss are two alarming,closely related problems,and the main factors triggering changes in land *** agricultural practices in the western Amazon Basin are known as chakras,and their structure and dynamics are seemingly optimal for forest ***,the variability in tree spe-cies and the degree of forest recovery after abandonment is poorly documented in this agroforestry system(afs).The goals of this study were:(i)to investigate whether the different afss(chakras)preserve similar levels of forest diversity,(ii)to determine the effect of trans-formation of mature forests(MF)to chakras,in particular,forest alpha and beta diversity levels,and(iii)to investigate whether native tree species recovery leads to the original forest structure following chakra *** We assessed the floristic composition in three afss(cassava,corn,and cocoa),the secondary forest(sF),and the forest remnants in the buffer zone of the Northern Ecuadorian Amazon(NEA).All tree spe-cies with a diameter at breast height(dbh)≥10 cm were inventoried in 61 plots(0.28 ha average)representing 17.44 *** diversity was calculated in all systems to determine the levels of variabil-ity using species richness and the shannon diversity ***,beta diversity was examined to evaluate the degree of dissimilarity among all afss with the MF in order to analyze changes in floristic *** divergence between the sF and the MF was ana-lyzed to ascertain forest recovery after chakra *** Findings A total of 4,060 trees(dbh≥10 cm)representing 109 species,96 genera,and 43 plant families were inventoried in 17.44 ha sampled in five systems in the buffer zone of the *** most dominant plant families were Arecaceae,Myristicaceae,Fabaceae,Meliaceae,and Malvaceae,and the most representative genera included Iriartea,Virola,Guarea,Ocotea,Cordia,Chrysophyllum,and *** MF in this zone is composed of 81 tree species circums

关键词： agroforestry biodiversity chakra climate change tropical forest

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Non-standard tests for process control in chemically bonded sands

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China Foundry 2016年第1期13卷 59-66页

作者： s.ramrattan Department of Engineering Design Manufacturing and Management Systems Western Michigan University

Chemically bonded sand cores and molds are more commonly referred to as precision sand systems in the high production automotive powertrain sector. Their behavior in contact with molten metal can lead to casting defects. Consequently, the interaction is of great interest and an important part of metal casting technology. The American Foundry society(afs) sand testing is based on physical, mechanical, thermal and chemical properties of the sand system. Foundry engineers have long known that certain afs sand tests provide limited information regarding control of molding and casting quality. The inadequacy is due to the fact that sand casting processes are inherently thermo-mechanical, thermo-chemical and thermo-physical. Non-standard foundry sand testing has proven useful for laboratory measurement of these characteristics in foundry sand using a disc-shaped specimen. similarly, the equivalent disc-shaped specimens are used for casting trials. In order to accomplish near-net-shape casting with minimal defects, it is necessary to understand both the properties of the sand system, as well as the interface of molten metal when different binders, additives and/or refractory coatings are used. The methodology for the following non-standard chemically bonded sand tests is described:(1) disc transverse;(2) impact;(3) modified permeability;(4) abrasion;(5) thermal distortion;(6) quick loss on ignition. The data related to the non-standard sand tests were analyzed and interpreted. The test results indicate that there is relatively lower test-to-test variability with the disc-shaped specimens. The non-standard tests were able to discriminate between the chemically bonded polyurethane cold box sand specimens. Further studies should be conducted on various other sand and binder systems as well as on different specimen thicknesses.

关键词： chemically bonded sand permeability test thermal distortion test loss on ignition

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Convolution-Based Heterogeneous Activation Facility for Effective Machine Learning of ECG signals

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Computers, Materials & Continua 2023年第10期77卷 25-45页

作者： Premanand.s sathiya Narayanan school of Electronics Engineering Vellore Institute of TechnologyChennai600127Indi

Machine Learning(ML)and Deep Learning(DL)technologies are revolutionizing the medical domain,especially with Electrocardiogram(ECG),by providing new tools and techniques for diagnosing,treating,and preventing ***,DL architectures are computationally more *** recent years,researchers have focused on combining the computationally less intensive portion of the DL architectures with ML approaches,say for example,combining the convolutional layer blocks of Convolution Neural Networks(CNNs)into ML algorithms such as Extreme Gradient Boosting(XGBoost)and K-Nearest Neighbor(KNN)resulting in CNN-XGBoost and CNN-KNN,***,these approaches are homogenous in the sense that they use a fixed Activation Function(afs)in the sequence of convolution and pooling layers,thereby limiting the ability to capture unique *** various afs are readily available and each could capture unique features,we propose a Convolutionbased Heterogeneous Activation Facility(CHAF)which uses multiple afs in the convolution layer blocks,one for each block,with a motivation of extracting features in a better manner to improve the *** proposed CHAF approach is validated on PTB and shown to outperform the homogeneous approaches such as CNN-KNN and *** PTB dataset,proposed CHAF-KNN has an accuracy of 99.55%and an F1 score of 99.68%in just 0.008 s,outperforming the state-of-the-art CNN-XGBoost which has an accuracy of 99.38%and an F1 score of 99.32%in 1.23 *** validate the generality of the proposed CHAF,experiments were repeated on MIT-BIH dataset,and the proposed CHAF-KNN is shown to outperform CNN-KNN and CNN-XGBoost.

关键词： Electrocardiogram convolution neural network machine learning activation function

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Design and Development of an Intelligent Energy Management system for a smart Grid to Enhance the Power Quality

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Energy Engineering 2023年第8期120卷 1747-1761页

作者： Nisha Vasudevan Vasudevan Venkatraman A.ramkumar T.Muthukumar A.sheela M.Vetrivel r.J.Vijaya saraswathi F.T.Josh Department of Electrical and Electronics Engineering Kalasalingam Academy of Research and EducationTamil NaduIndia Department of Computer science Engineering Kalasalingam Academy of Research and EducationTamil NaduIndia Department of Electrical and Electronics Engineering Kongunadu College of Engineering and TechnologyTamil NaduIndia Department of Electrical and Electronics Engineering Kongu Engineering CollegeTamil NaduIndia Department of Electrical and Electronics Engineering Narasu’s Sarathy Institute of TechnologyTamil NaduIndia Department of Electrical and Electronics Engineering Panimalar Engineering CollegeTamil NaduIndia Department of Electrical and Electronics Engineering Karunya Institute of Technology&SciencesTamil NaduIndia

MigroGrid(MG)has emerged to resolve the growing demand for *** because of its inconsistent output,it can result in various power quality(PQ)*** is a problem that is becoming more and more important for the reliability of power systems that use renewable energy ***,the employment of nonlinear loads will introduce harmonics into the system and,as a result,cause distortions in the current and voltage waveforms as well as low power quality issues in the supply ***,this research focuses on power quality enhancement in the MG using hybrid shunt ***,the performance of the filter mainly depends upon the design,and stability of the *** efficiency of the proposed filter is enhanced by incorporating an enhanced adaptive fuzzy neural network(AFNN)*** performance of the proposed topology is examined in a MATLAB/simulink environment,and experimental findings are provided to validate the effectiveness of this ***,the results of the proposed controller are compared with Adaptive Fuzzy Back-stepping(AFBs)and Adaptive Fuzzy sliding(afs)to prove its superiority over power quality improvement in *** the analysis,it can be observed that the proposed system reduces the total harmonic distortion by about 1.8%,which is less than the acceptable limit standard.

关键词： Artificial intelligence resistive inductive load shunt hybrid filter smart grid adaptive fuzzy back-stepping power factor

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Development of a Flameless and Low Temperature Atomizer Based on Dielectric Barrier Discharge for Atomic Fluorescence spectrometry

Development of a Flameless and Low Temperature Atomizer Base...

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第三十五届国际光谱会议

作者： Z.L.Zhu~1 J.X.Liu~2 s.C.Zhang~(1*) Z.Xing~1 X.r.Zhang~(1*) ~1Department of Chemistry,Key Laboratory for Atomic and Molecular Nanosciences of the Education Ministry,Tsinghua University,Beijing 100084,P.r.China ~2Jitian Instrument Co,Ltd,Beijing 100016,P.r.China

A new flameless atomizer based on atmospheric pressure dielectric barrier discharge (DBD)plasma specially designed for atomic fluorescence spectrometry(afs)is *** characteristics of the DBD atomizer and the effects of...

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Challenging the Expiry Dates of Two Mycotoxins standards: Afla and Ochra A

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Journal of Materials science and Chemical Engineering 2017年第8期5卷 59-68页

作者： A. Aridi L. Baydoun C. M. s. T. sukhn Chemistry Department Faculty of Sciences II Lebanese University Fanar Lebanon Environment Core Laboratory Pathology & Laboratory Medicine Department Faculty of Medicine American University of Beirut Hamra Beirut Lebanon

Objectives: To challenge the expiry dates of low concentration high purity mycotoxins standards. Literature review: Aflatoxins (afs) and Ochratoxin A (OTA) are persistent mycotoxins with adverse effects on humans. Mycotoxins standards are purchased to determine mycotoxin concentrations in food and may be stocked in some laboratories beyond expiry dates causing laboratories financial losses. Methods: Certified mycotoxins standards were purchased over the years from the same supplier at times and at other times from two different suppliers for quality control purposes. For afs, six chromatographic runs for each of the mycotoxins standards were done to compare the difference among these standards having the following expiry dates (2008, 2012, 2013 and 2018). afs standards purchased/obtained from two different suppliers in 2016 and expiring in 2018 were also compared. For OTA, the difference of concentration obtained between two years (2010 and 2018) was tested. All samples were run on a HPLC equipped with a fluorescence detector. Linearity of calibration curves and the points of lowest detection were determined for afs components and for OTA from the unexpired mycotoxins standards. results: At a 0.05 significance level and using non parametric tests, the statistical test revealed a p of 0.166, 0.153, 0.358 and 0.03 for B1, G1, B2 and G2 respectively among years for standards from same supplier and 0.037, 0.109, 0.182 and 0.182 for B1, G1, B2 and G2 respectively for unexpired standards from two different suppliers. For OTA, a p of 0.109 was obtained for standards of different expiry dates purchased from different suppliers. Conclusion: High purity low concentration mycotoxin standards purchased a decade ago (i.e. expired) did not differ from those purchased this current year (still valid). Hence, the expiry date can be renewed reducing the laboratories expenses. Manufacturers are urged to reconsider the expiry dates.

关键词： Mycotoxins Aflatoxins Ochratoxin A G1 G2 B1 B2 OTA Persistent Ther-mostable standards Certified Low Concentration High Purity Challenge Expiry Date Years HPLC Manufacturer suppliers

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Productivity, Leaf Nutrient Content and soil Carbon stocked in Agroforestry and Traditional Management of Maize (<i>Zea mays</i>L.)

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American Journal of Plant sciences 2014年第6期5卷 884-898页

作者： Maria J. A. Bertalot Iraê A. Guerrini Eduardo Mendoza Mauro s. V. Pinto Brazilian Association of Biodynamic Agriculture Botu-catu Brazil Department of Natural resources/soil science FCA UNESP Botucatu SP Brazil Embrapa Agroindústria de Alimentos Rio de Janeiro Brazil

The aim of the work was to evaluate the productivity, leaf nutrient content and soil nutrient concentration in maize (Zea mays L.) grown in sequence with black oats (Avena strigosa schreb.) under Leucaena diversifolia alley cropping agroforestry system (afs) and traditional management system/sole crop (without trees-Ts), after two years of cultivation following a randomized block design. The experiment was carried out in the Brazilian Association of Biodynamic Agriculture, in Botucatu—s?o Paulo, Brazil. Treatments were: control (C), chemical fertilizer application (F), biomass of L. diversifolia alley cropping application (B), biomass of L. diversifolia alley cropping + chemical fertilizer application (B + F). In the second year of management it was observed that black oat yield was higher in treatments B + F and F with significant difference in relation to the others treatments in both systems, followed by treatment B. Between systems, only treatment B showed significant difference, with higher yield value corresponding to afs, reflecting the efficiency of afs to promote soil fertility. Maize production presented the second year of cultivation an increasing trend in all treatments in both production systems. This result may be due to the cumulative effect of mineralization and maize straw and oats, along the experiment. How productivity was higher in the afs system, could also be occurring effect of biological nitrogen fixation, water retention and reduction of extreme microclimate through the rows of L. diversifolia. Comparing the afs and Ts, it was observed that the concentration of N in leaf tissue was higher in the afs treatments, probably due to nitrogen fixation performed through the rows of L. diversifolia, that is a nitrogen fixing tree species. After two years, carbon stocked in soil show higher values in the treatments biomass + fertilizer and biomass application, in both systems, afs and Ts.

关键词： Alley Cropping Leucaena diversifolia Crop sequence Green Manure soil Nutrient Concentration soil Organic Matter Carbon stocked in soil

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THE sYsTEMs BAsED ON THE afs FUZZY LOGIC

THE SYSTEMS BASED ON THE AFS FUZZY LOGIC

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第二十届中国控制会议

作者： Liu Xiaodong Zhang Qingling and Wei Hua Dept. of Basic science, Dalian Maritime University, Dalian 116026, P. r. China College of sciences, Northeastern University, shenyang, P. r. China

＜正＞In this paper, by an example, we show that both Mamdani fuzzy logic systems and sAM fuzzy logic systems lost some important expert information in the process of establishing the systems and this defect of Mamdani fuzzy logic systems can not be improved by choosing different T-norm and s-norm. We establish a new system based on the afs fuzzy logic. It shows that this new system preserve more expert information than Mamdani and sAM fuzzy systems and the engineers can design fuzzy logic controllers by this new system.

关键词： fuzzy logic systems afs structures afs algebra afs Fuzzy logic.

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珊瑚的AMs14C和Ms U-Th测试

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海洋地质前沿 1993年第6期 12-14页

作者： G.s.Burr 业渝光

U-Th测年的原理为人们所知已有多年,然而这种方法由于不能精确地测定U/U和Th/U而受到了限制。质谱计（Ms）测试这些核素方法的发展,使我们得到的U-Th年龄象C那样精确甚至比C年龄还精确.采用质谱计确定U和Th的同位素丰度现在能够精确地... 详细信息

U-Th测年的原理为人们所知已有多年,然而这种方法由于不能精确地测定U/U和Th/U而受到了限制。质谱计（Ms）测试这些核素方法的发展,使我们得到的U-Th年龄象C那样精确甚至比C年龄还精确.采用质谱计确定U和Th的同位素丰度现在能够精确地测定距今50a—500ka左右时间范围内的珊瑚年龄。

关键词：重结晶作用 afs 方解石 Ms U-Th AMs

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ICP荧光光谱法测定溶液中金属的最佳条件选择

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光谱学与光谱分析 1985年第6期 3-3页

作者： r.L.Lancione,s.J.Evans,胡昌媛 Baird Corporation Bedford MA 01730 U.s.A. Baird Corporation Bedford MA 01730 U.s.A.

ICP仪器正日益增长地广泛应用于非水溶液的分析。即使ICP样品引入系统对某类样品要求稀释,光度计灵敏度也能很好地满足大多数分析的需要。ICP原子荧光光度计是由高温原子化池(ICP)与分光技术组合而成,以避免谱线干扰及基线飘移。在此研... 详细信息

ICP仪器正日益增长地广泛应用于非水溶液的分析。即使ICP样品引入系统对某类样品要求稀释,光度计灵敏度也能很好地满足大多数分析的需要。ICP原子荧光光度计是由高温原子化池(ICP)与分光技术组合而成,以避免谱线干扰及基线飘移。在此研究中,应用于收集数据的afs-2000型仪器是常规用于测定各种水溶液介质中痕量元素的。为了将所操作的水溶液转换为有机溶液,样品引入系统须用乙醇清洗。

关键词： ICP 仪器

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