Tópicos Sugeridos dentro de su búsqueda.
Tópicos Sugeridos dentro de su búsqueda.
Buscar alternativas:
tree based » time based (Expander búsqueda), career based (Expander búsqueda), breeds based (Expander búsqueda)
tree based » time based (Expander búsqueda), career based (Expander búsqueda), breeds based (Expander búsqueda)
1
artículo
Publicado 2022
Enlace
Enlace
With the increasing popularity of online social networking platforms, the amount of social data has grown exponentially. Social data analysis is essential as spamming activities and spammers are escalating over online social networking platforms. This paper focuses on spammer detection on the Twitter social networking platform. Although existing researchers have developed numerous machine learning methods to detect spammers, these methods are inefficient for appropriately detecting spammers on Twitter due to the imbalance of spam and nonspam data distribution, the involvement of diverse features and the applicability of data mechanisms by spammers to avoid their detection. This research work proposes a novel hybrid approach of the gravitational search algorithm and the decision tree (HGSDT) for detecting Twitter spammers. The individual decision tree (DT) algorithm is not able to address...
2
artículo
Publicado 2024
Enlace
Enlace
In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These re...
3
artículo
Publicado 2025
Enlace
Enlace
Forest volume modeling plays a fundamental role in forest inventory, biomass estimation, and the sustainable management of timber resources. In the Amazon region of Peru, native species such as Calycophyllum spruceanum and Cedrelinga cateniformis hold high ecological and commercial value, yet remain understudied in terms of volumetric estimation. This study aimed to develop and evaluate volumetric models for both species across three ecological zones—humid forest, very humid forest, and dry forest—representing the environmental diversity of the northeastern Peruvian Amazon. A total of 18 volumetric models were fitted for each species and site condition using linear regression techniques. Model performance was assessed through adjusted coefficient of determination (R²adj), root mean square error (RMSE), mean absolute error (MAE), Akaike Information Criterion (AIC), and diagnostic ana...
4
artículo
Publicado 2024
Enlace
Enlace
The characterization of soil microbial communities at different depths is essential to understand their impact on nutrient availability, soil fertility, plant growth and stress tolerance. We analyzed the microbial community at three depths (3 cm, 12 cm, and 30 cm) in the native fruit trees Annona cherimola (cherimoya) and Pouteria lucuma (lucuma), which provide fruits in vitamins, minerals, and antioxidants. We used PacBio-HiFi, a long-read high-throughput sequencing to explore the composition, diversity and putative functionality of rhizosphere bacterial communities at different soil depths. Bacterial diversity, encompassing various phyla, families, and genera, changed with depth. Notable differences were observed in the alpha diversity indices, especially the Shannon index. Beta diversity also varied based on plant type and depth. In cherimoya soils, positive correlations with Total Or...
5
artículo
Publicado 2025
Enlace
Enlace
The soils of Mexico City (CDMX) are heterogeneous, compact, with an alkaline pH, and with low microbiological diversity. In this context, the objective of the present study was to explore the diversity of filamentous fungi in Canarian palm soils with contrasting health conditions during the dry and rainy season 2022. 55 Canary Island palms with different health categories were sampled. From each one, soil was collected from two concentric rings and samples composed of each ring and each palm were formed, for which the pH and electrical conductivity were first determined. To know their fungal populations, the soil dilution technique in PDA-TS (potato-dextrose-agar-tergitol-streptomycin) culture medium was used. Identification was based on cultural and morphological characteristics. In the soils of the study area, a richness of seven fungal species was found, Aspergillus niger was the most...
6
artículo
Publicado 2024
Enlace
Enlace
Diversos autores ponen de manifiesto que, para poder realizar una adecuada gestión sostenible de los ecosistemas forestales, es de vital importancia tener la capacidad de conocer la estructura espacial de los bosques y las modificaciones que le puede ocasionar debido al aprovechamiento forestal para gestionar de manera sostenible los ecosistemas forestales. Los objetivos de este estudio fueron examinar y caracterizar el patrón espacial del tornillo (Cedrelinga cateniformis (Ducke) Ducke) y guabilla (Inga thibaudiana DC.), así como analizar su relación con la altitud (m) sobre el nivel del mar, la distancia (m) de los árboles aprovechables hasta un río y la distancia (m) de los árboles aprovechables hasta un árbol semillero. El análisis estadístico se realizó a través de las herramientas del análisis de patrones puntuales espaciales, que proveen un conjunto de métodos para e...
7
tesis de grado
El presente plan de negocios se encuentra en el rubro de comercialización de productos ecológicos, la empresa se dedicará a la elaboración y venta de carbón ecológico, elaborado a base de cáscara de coco, abastecida por los principales negocios dedicados a la venta de coco helado, quienes envían sus desperdicio al relleno sanitario. El aprovisionamiento de la materia prima se realizara en la ciudad de Tarapoto, ciudad conocida como la ciudad de las palmeras, por su alta producción de coco. En cuanto a la estructura organiza fue diseñada para una micro empresa, la que cuenta con funciones integradas para cada área. La empresa se acogerá al régimen laboral general. El plan económico y financiero ha determinado la rentabilidad del negocio, presenta el Valor actual neto económico (VAN) de S/. 238,020 y el Valor actual neto financiero de S/. 239,693. La Tasa interna de retorno ...
8
artículo
Publicado 2015
Enlace
Enlace
Los Andes están considerados como los puntos calientes más diversos de los trópicos, dentro de estos se encuentra el Parque Nacional del Manu, cuyas complejas condiciones climáticas y fisiográficas albergan una mega-diversidad y endemismo. En el presente trabajo se presenta una lista anotada de especies arbóreas y afines a lo largo de un gradiente de elevación desde los bosques submontanos a 800 m hasta la línea de bosque a 3625 m en la Reserva de Biosfera del Manu. En base a una red de 21 parcelas permanentes de una hectárea y exploraciones botánicas se sistematiza la información florística por rangos de elevación, distribución geográfica y endemismo. Estos resultados preliminares se traducen en 1108 especies de las cuales el 39.7% son morfoespecies, el 43% de las especies determinadas son registros nuevos para la región del Cusco, 15 especies son nuevos registros para l...
9
artículo
Publicado 2015
Enlace
Enlace
The tropical Andes and adjacent Amazon are Earth’s highest biodiversity hotspot. Manu National Park in southeastern Peru encompasses an entire watershed, ranging from Andean highlands to Amazonian lowlands, and is a megadiverse landscape on the Andes to Amazon transition. Here we present an annotated checklist of trees and related species is along an elevation gradient in the Manu Biosphere Reserve that runs from sub-montane forests at 800 m elevation up to the tree line at 3625 m. Based on a network of 21 1-hectare permanent tree plots and botanical explorations, the floristic information is systematized by elevation ranges, geographical distribution and endemism. These preliminary results show 1108 species. Of these, 43% are new records for the region of Cusco, 15 species are new records for the Peruvian flora, 40 species are endemics for Peru, and 30 are potential new species for sc...
10
tesis de grado
Implementación de un sistema señalético y nueva identidad visual para el Vivero Forestal de Chimbote
Publicado 2022
Enlace
Enlace
El siguiente proyecto tiene como objetivo diseñar un sistema visual unificado y versátil, capaz de brindar una experiencia visual y de valor única a los usuarios del Vivero Forestal de Chimbote. Para ello se desarrolló en desarrollar una identidad visual corporativa que comunique conceptos representativos del recinto, y que además cumpla con la apropiada escalabilidad, simplicidad y representatividad. Por otro lado, también se busca implementar un sistema que se armonice con el ambiente, y sea reconocido por los usuarios, logrando que puedan recorrer el vivero sin desorientarse o perderse de ninguna atracción. Ahora bien, dichos objetivos nacen en base a que a las personas les cuesta ubicarse dentro del lugar, esto debido a que el vivero no cuenta con un sistema señalético actualizado. Lo que provoca que la experiencia de usuario se vea perjudicada. La relevancia del proyecto se...
11
artículo
Fabrication and thermomechanical evaluation in controlled atmospheres of SiC/Si biomorphic compounds
Publicado 2020
Enlace
Enlace
Biomorphic SiC/Si compounds were fabricated from copaiba wood (Copaifera officinalis, natural wood native to Peru), by reactive infiltration of molten silicon in a porous carbon preform obtained by a controlled pyrolysis process of wood. Structural and microstructural characterization tests by X-ray diffraction and scanning electron microscopy, respectively, revealed, on the one hand, the presence of crystalline phases of SiC, Si and C, and on the other, the typical morphology of this type of material, which it consists of a continuous SiC scaffold with elongated channels in the direction of tree growth and the presence of residual Si and C located mainly in the porosities of the material. The mechanical behavior in uniaxial compression was also studied at a constant compression rate of 0.05 mm/min and as a function of temperature (from ambient to 1400 ºC) and test atmosphere (ambient a...
12
artículo
Publicado 2023
Enlace
Enlace
The objective of this paper was to estimate the volume of a secondary forest located in the Chanchamayo valley by means of a volume equation as a function of crown diameter from the information captured by a remotely piloted aircraft system (RPAS). With the digital RGB camera of the RPAS, photographs of the secondary forest were taken with a 90% overlap between them. The flights were made at different heights, selecting the photographs taken at 100 m above ground level. With them, photomosaics were made, in which a sample of 50 trees whose crowns were visible was taken. These trees were measured in the field, obtained dbh, diameters at different heights, stem height and crown radius. The stem volume of each tree was calculated with the Smalian formula. With the data, it was determined that there are no significant differences between the crown diameters calculated in the field and those ...
13
tesis de maestría
Publicado 2023
Enlace
Enlace
En nuestro país, la cantidad promedio de denuncias por delitos de manera mensual en el año 2019 presenta 30,000 casos, lo cual se ha ido incrementando a lo largo de los años, por lo que es de crucial importancia generar estrategias de seguridad ciudadana que ayuden a mejorar el bienestar de la sociedad peruana, para ello es crucial tener información fiable y de calidad para la toma de decisiones; asimismo, tiene una Dirección de Tecnologías de la Información y Comunicación de la Policía (DIRTIC), la cual dentro de su estructura tiene a su cargo a la División de Estadística (DIVEST) y la División de Informática (DIVINFOR), las cuales tienen como función el control del Sistema de Denuncias Policiales en la cual el 80 % de las comisarías de la Policía Nacional del Perú se encuentran interconectadas y existe un 20 % que no se encuentran interconectadas, por lo cual el 20 % ...
14
artículo
Maximum-minimum bidirectional options are a kind of exotic path dependent options. In the constant elasticity of variance (CEV) model a combining trinomial tree was structured to approximate the nonconstant volatility that is a function of the underlying asset. On this basis a simple and efficient recursive algorithm was developed to compute the risk-neutral probability of each different node for the underlying asset reaching a maximum or minimum price and the total number of maxima (minima) in the trinomial tree. With help of it the computational problems can be effectively solved arising from the inherent complexities of different types of maximum-minimum bidirectional options when the underlying asset evolves as the trinomial CEV model. Numerical results demonstrate the validity and the convergence of the approach mentioned above for the different parameter values set in the trinomial...
15
artículo
Publicado 2020
Enlace
Enlace
Key message Soil pH, EC, and salinity explain the leaf nutrient concentrations ofProsopis pallidadespite the high amount of soil nutrients near the trees. Dryland forests constantly face extreme abiotic conditions, and this affects plant growth and nutrition. We have determined the effects of soil chemical attributes and soil nutrients on the leaf nutrient concentrations of eightProsopis pallidapopulations located along a climatic gradient in the North-Peruvian dryland forests. We analyzed the leaf chemical composition (N, P, K, Ca, Mg, Fe, Mn, Cu, and Zn), as well as soil chemical attributes [texture, pH, salinity (electrical conductivity; EC), and the sodium adsorption ratio (SAR)] and soil nutrient concentrations (the same elements as in the leaves) at 2 m from the base of each tree. The soil and leaf nutrient concentrations were not associated with the climatic gradient and were high...
16
tesis de grado
Publicado 2024
Enlace
Enlace
Universidad Nacional Agraria La Molina. Facultad de Ciencias Forestales. Departamento Académico de Manejo Forestal
17
artículo
Publicado 2021
Enlace
Enlace
Key message: Soil pH, EC, and salinity explain the leaf nutrient concentrations of Prosopis pallida despite the high amount of soil nutrients near the trees. Abstract: Dryland forests constantly face extreme abiotic conditions, and this affects plant growth and nutrition. We have determined the effects of soil chemical attributes and soil nutrients on the leaf nutrient concentrations of eight Prosopis pallida populations located along a climatic gradient in the North-Peruvian dryland forests. We analyzed the leaf chemical composition (N, P, K, Ca, Mg, Fe, Mn, Cu, and Zn), as well as soil chemical attributes [texture, pH, salinity (electrical conductivity; EC), and the sodium adsorption ratio (SAR)] and soil nutrient concentrations (the same elements as in the leaves) at 2 m from the base of each tree. The soil and leaf nutrient concentrations were not associated with the climatic gradien...
18
tesis de grado
Publicado 2019
Enlace
Enlace
La identificación de especies de Hongos Micorrízicos Arbusculares (HMA), presentes en áreas donde se cultiva el café (Coffea arabica L.) en nuestra Región son de gran importancia, pues constituye la base para la investigación de especies que pueden ser aprovechadas en el futuro como bioprotectores y biofertilizantes en este cultivo y así contribuir al mejoramiento sostenible de la producción. En este sentido, se identificó 31 especies de HMA, en suelos de doce localidades (fuentes de inóculo) de plantaciones de café, de la cuales se reportó una especie nueva (Funneliglomus sanmartinense), estando presente especialmente en Alto Palmiche (Lamas). De las localidades muestreadas, Pueblo Nuevo (Lamas) y Nuevo Lamas (San Martín) fueron las fuentes de inóculo que tuvieron mayor densidad de esporas y riqueza de especies, siendo de las dos, Nuevo Lamas la localidad que proporcionó ...
19
objeto de conferencia
Publicado 2023
Enlace
Enlace
A predictive model is a good technique for prognosticating the life cycle of medical care services (LCMCS) related to its growth, stability, and decline to support information processes and decision-making based on intelligent forecasts. Medical care services require organization, scheduling, and programming attention to prevent the capacity of medical personnel. Otherwise, it could be chaotic. This research aims to evaluate three predictive models to find the best one to fit information about the LC-MCS and understand medical care services' behavior in healthcare entities. The proposed model applied to Ricardo Palma Clinic (RPC) in Lima Perú analyzes the LC-MCS information based on 4950 clinical health records. Three predictive models were trained and compared to evaluate the accuracy of backpropagation neural networks, decision trees, and multiple linear regression models. After train...
20
tesis de maestría
Publicado 2021
Enlace
Enlace
La eficiencia energética de un centro de datos está en razón de la energía consumida total por el centro de datos y la energía consumida por los sistemas de cómputo, conocido como PUE. En el presente proyecto se desarrolla una alternativa para reducir el consumo de energía en un centro de datos, manteniendo encendidos solo los recursos de red que se utilizan para cursar el tráfico que atraviesa la red en un momento dado. Para esto, nos enfocamos específicamente en los dispositivos de conectividad: conmutadores, sus puertos y los enlaces que los conectan; y no el resto de la infraestructura. Actualmente las tecnologías de red están adoptando un nuevo paradigma: las redes definidas por software. Con ellas se abre la posibilidad de controlar, de manera centralizada, dispositivos de red a través de aplicaciones que pueden ser desarrolladas por los administradores de red, automati...
