504 research outputs found
ASSESSING RED PINE SEEDLINGS USING UAV POINT CLOUDS AND FIELD-VERIFIED DATA
Accurate, reliable, and cost-efficient approaches to forest monitoring are critical for sustainable forest management. The use of digital photogrammetry for tree height estimation is well-known among forest managers and remote sensing researchers. Satellite remote sensing has not been very successful in providing detailed and reliable estimates of tree height. Unmanned Aerial Vehicles (UAVs) are one of the latest remote sensing platforms to get forest attributes information at very high temporal and spatial resolution. This study assessed the potential of using digital aerial photogrammetry point clouds and UAV acquired high-resolution imagery to estimate red pine seedlings' height in Adirondacks, New York. Seedling's location, height, crown width, and diameter were measured from 16 fixed area sample plots, and multispectral imagery was acquired with DJI Matrice 100- UAV fitted with Micasense RedEdge-M camera. UAV was flown under clear sky conditions at 93-meter height in a single grid pattern with 80% front and side overlap. PIX4D software was used to process UAV multispectral imagery and generate Digital Surface Model (DSM) and Orthomosiac at 6.08 cm/pixel resolution along with 3D Digital Terrain Model (DTM). 3D densified point cloud layers of regeneration canopy were generated at an average density of 1.54 per m3. Seedlings were differentiated from bare ground cover through supervised image classification methods. Preliminary results of this study highlight that multispectral imagery acquired from UAVs has the potential to characterize and provide detailed structural information to estimate red pine seedlings' height
Developing new joining materials for low-temperature electronics assembly
International audienceThe present work focuses on a new kind of lead-free joining method for surface-mount technology based on precursor chemistry. The interest of metal oxalates as new soldering materials for die attachment (1st level packaging) was previously demonstrated with silver oxalate. The thermal decomposition of metal oxalates under controlled atmosphere can be used to produce small metal particles below their melting point. These particles are found to be in a highly active particulate form. First experimental studies are focusing on several metal oxalates (tin oxalate and bismuth oxalate) to assess their suitability for low-temperature metal particle production. The main work is dealing with controlled chemical precipitation synthesis and characterization of the compounds as well as study of the properties of decomposition solid products (powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy and thermal analyses under different atmospheres)
Efficient Ray-Tracing Channel Emulation in Industrial Environments: An Analysis of Propagation Model Impact
Industrial environments are considered to be severe from the point of view of
electromagnetic (EM) wave propagation. When dealing with a wide range of
industrial environments and deployment setups, ray-tracing channel emulation
can capture many distinctive characteristics of a propagation scenario.
Ray-tracing tools often require a detailed and accurate description of the
propagation scenario. Consequently, industrial environments composed of complex
objects can limit the effectiveness of a ray-tracing tool and lead to
computationally intensive simulations. This study analyzes the impact of using
different propagation models by evaluating the number of allowed ray path
interactions and digital scenario representation for an industrial environment.
This study is realized using the Volcano ray-tracing tool at frequencies
relevant to 5G industrial networks: 2 GHz (mid-band) and 28 GHz (high-band).
This analysis can help in enhancing a ray-tracing tool that relies on a digital
representation of the propagation environment to produce deterministic channel
models for Indoor Factory (InF) scenarios, which can subsequently be used for
industrial network design.Comment: copyright 2023 IEEE. Personal use of this material is permitted.
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Applications of the new Remote Sensing Method to the Forest Biomass Estimation
For accurate measurement of forest biomass in the Akazawa Forest Reserve, this study analyzed texture measures derived from GeoEye-1 satellite data using the individual tree crown (ITC) method. On this basis, canopy area, tree tops and tree species of individual trees were delineated. Canopy area was used to calculate the DBH of trees in canopy layer based on canopy-DBH curve in this stand. In this study, the estimation models, between DBH and height, and between canopy area and DBH were developed by linear regression using forest survey data. Then according to the results of satellite data interpreted the biomass of every tree was calculated by biomass expansion factor (BEF). This method was verified against the survey data from old–growth Chamaecyparis obtusa stand composed of various cover types. For Chamaecyparis obtusa, the accuracy of biomass estimation was higher than 84%. However, the accuracy of Chamaecyparis pisifera was less than 60%, because some Chamaecyparis pisifera trees were misidentified as Chamaecyparis obtusa, and canopy area of Chamaecyparis pisifera was underestimated in the high-density stand. For Thujopsis dolabrata, the accuracy ranged from 22.4 % to 78.9%, and from 63.4% to 84.6% for broad-leaved trees, because many of them were understory. These results indicated that estimation of old-growth forest biomass based on high resolution satellite data, might be validated for estimating biomass at the individual tree level improved by developing and applying forest stratum–specific models with the ITC-survey data as a bridging reference in addition to spectral information. This approach is useful for biomass estimation whether is used to calculate biomass of individual tree or forest.ArticleThe International Journal of Sciences. 2(8):1-13 (2013)journal articl
Some rural examples of place-based education
There are important issues for rural communities in Australia in relation to the provision of education for their young people. This is particularly so in an era when successful completion of education is becoming increasingly vital as the pressures of a globalised economy mean that many rural and farming businesses are struggling to prosper. The term 'place-based education' is used by educators and researchers who have a focus on the well-being and effective learning of students. This paper explores what is meant by 'place-based education' and how this concept of education is being implemented in some rural schools in Australia, although usually without using this term. A review of literature about effective literacy learning demonstrates why teaching that is place-based is important for rural students. What the implementation of place-based education might look like in rural schools is also explored
Sarana Transportasi Penunjang Riset Penelitian Di Kawasan Hutan Mangrove
Indonesia has the largest mangrove's forest. 5.3 million of 8.6 million hectare of the forest has been damages. (Gunarto, 2004).Start from 1960 there are mangrove's forests been open became shrimp's embankment. That made land defense became low against abrasion and big waves.Rehabilitation of the destruction of mangroves currently being conducted. The research was done in order to know the current state of the forest. Researchers use various ways to present the best data.In this report there are developing in research's equipment at mangrove's forest. Peculiarities and natural contours of mangrove's forest make people used a different transportation. Plus research equipment that must be taken and the number of objects of research that should take also became a challenge to be considered and addressed.Transportation at mangrove's forest, especially in waters, that correspond to the natural condition is light small ship that stable and has a wide space in ship
Efeito da proteĂna morfogenĂ©tica Ăłssea 7 (BMP-7) para a sobrevivĂŞncia in vitro de folĂculos prĂ©antrais caprino
O presente trabalho foi conduzido de modo a se verificar o efeito de diferentes concentrações da BMP-7 no desenvolvimento in vitro de folĂculos prĂ©-antrais caprinos. Fragmentos de tecido cortical ovariano caprino foram cultivados por 1 ou 7 dias em Minimum Essential Medium (MEM+) suplementado com diferentes concentrações de BMP-7 (1, 10, 50 ou 100ng/ml). Os fragmentos nĂŁo cultivados ou aqueles cultivados por 1 ou 7 dias foram processados para histologia clássica e microscopia eletrĂ´nica de transmissĂŁo (TEM), sendo avaliados parâmetros morfolĂłgicos indicativos de viabilidade, ativação e crescimento. Os resultados mostraram que o percentual de folĂculos morfologicamente normais diminuiu significativamente em todos os tratamentos quando comparados ao controle, exceto na concentração de 1ng/ml por 1 dia de cultivo. Já no D7 todos os tratamentos reduziram significativamente os percentuais de folĂculos morfologicamente normais. Utilizando 10ng/ml de BMP-7 foi observado um aumento significativo no diâmetro folicular quando comparados os diferentes perĂodos de cultivo. NĂŁo houve influĂŞncia das demais concentrações de BMP-7 quando avaliados alĂ©m do diâmetro folicular o diâmetro oocitário. A análise por TEM confirmou a integridade ultra-estrutural nos folĂculos apĂłs 7 dias de cultivo com 1ng/ml de BMP-7 . Em conclusĂŁo, o BMP-7 em baixas concentrações pode melhorar a sobrevivĂŞncia e o crescimento durante o cultivo in vitro de folĂculos prĂ©-antrais caprinos.This study was conducted in order to verify the effect of different concentrations of BMP-7 in the in vitro survival and development of caprine preantral follicles. Fragments of caprine ovarian cortical tissue were cultured for 1 or 7 days in Minimum Essential Medium (MEM+) supplemented with different concentrations of BMP-7 (1, 10, 50 or 100ng/ml). Noncultured fragments or those cultured for 1 or 7 days were processed for classical histology and transmission electron microscopy (TEM). Parameters such as follicular survival, activation and growth were evaluated. The results showed that, after 1 or 7 days of culture, the percentage of morphologically normal follicles was significantly reduced in all treatments when compared with fresh control, except at 1ng/ml of BMP-7 for 1 day. In addition, the concentration of 10ng/ml of BMP-7 significantly increases follicular diameter from day 1 to 7 of culture. There was no influence of the other concentrations of BMP-7 regarding to the follicular and oocyte diameter. Ultrastructure studies confirmed follicular integrity after 7 days of culture in 1ng/ml BMP-7. In conclusion, small concentrations of BMP-7 can improve the survival and growth of caprine preantral follicles during in vitro culture
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