854 research outputs found
A Semi-Automated Computational Approach for Infrared Dark Cloud Localization: A Catalog of Infrared Dark Clouds
The field of computer vision has greatly matured in the past decade, and many
of the methods and techniques can be useful for astronomical applications. One
example is in searching large imaging surveys for objects of interest,
especially when it is difficult to specify the characteristics of the objects
being searched for. We have developed a method using contour finding and
convolution neural networks (CNNs) to search for Infrared Dark Clouds (IRDCs)
in the Spitzer Galactic plane survey data. IRDCs can vary in size, shape,
orientation, and optical depth, and are often located near regions with complex
emission from molecular clouds and star formation, which can make the IRDCs
difficult to reliably identify. False positives can occur in regions where
emission is absent, rather than from a foreground IRDC. The contour finding
algorithm we implemented found most closed figures in the mosaic and we
developed rules to filter out some of the false positive before allowing the
CNNs to analyze them. The method was applied to the Spitzer data in the
Galactic plane surveys, and we have constructed a catalog of IRDCs which
includes additional parts of the Galactic plane that were not included in
earlier surveys.Comment: 17 pages, 18 figures, one machine-readable table. Accepted for
publication in the PAS
Preliminary evaluation of a short rotation forestry poplar biomass supply chain in Emilia Romagna Region
Two prototypes for medium rotation forestry harvesting
Five years old poplar (Populus spp.) plantation represents an interesting model of productivity. The most attractive characteristics of this energy crop are the handling flexibility, the high yield of biomass per area unit and the good quality of the chips obtainable. The mechanical harvesting of five-years old poplar plantations requires the use of specialized forest machineries such as harvester, feller, forwarder and chipper. Usually, after felling, the working phases consist of extraction, stacking and chipping. Generally, the last one is carried out in a “static phase”, where the product is taken from staked logs by using a hydraulic arm having a gripper that feed the chipping machine. In order to introduce technological innovations for the medium rotation forestry harvesting, the Consiglio per la Ricerca e la sperimentazione in Agricoltura, Unità di ricerca per l’Ingegneria agraria (CRAING) of Monterotondo (Rome, Italy) has developed a five years poplar cutwindrower and a self-propelled chipper equipped with a pick up system. The prototype of cut-windrower is a semi-trailed machine powered by a 95 kW tractor (at least). It mounts a cutting system and a double pincer with variable positioning. During the cutting phase the plant is grasped by the double pincer which conveys and unloads the stem along the inter-row. The trees are placed parallel to the progress of the tractor, but oriented in the opposite direction. The biomass windrowed is then chipped in a dynamic phase directly from the inter row using the self-propelled chipper equipped with the pick-up head. In the first tests, the cut-windrower has reached an operative working capacity of 0.22 ha h-1, with an operative production of 44 t h-1. On the other hand, the self-propelled chipper has showed an operative working capacity equal to 0.18 ha h-1, and an operative production of 35 t h-1 about. Both machines have shown good quality of the work performed and the results obtained indicates that the work phases could be simplified in order to reduce both the time of use and the harvesting costs
Differentiation of Three Phenotypically Similar \u3ci\u3eBlattella\u3c/i\u3e spp.: Analysis with Polymerase Chain Reaction-Restriction Fragment Length Polymorphism of Mitochondrial DNA
Differentiation of Blattella asahinai Mizukubo, Blattella vaga Hebard, and Blattella germanica (L.) was investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). DNA fragments corresponding to mitochondrial CO1,CO1/TL2(small and large fragments), and ITS2 regions were amplified using PCR. The universal primers used for amplifying mitochondrial CO1 and CO1/TL2 (small and large fragments) were CO1-J-1718/CO1- N-2191, CO1-J-2441/TL2-N-3014, and CO1-J-1751/TL2-N-3014. Amplification was observed with all primer combinations, but diagnostic patterns were found only with AluI digested amplicons of CO1 and CO1/TL2 (large fragments) regions. Both inter/intraspecific polymorphism was observed for the 517 bp CO1 region between German (A, B) and Asian (A, B, C) cockroach populations. Polymorphic form B of the Asian cockroach (374 and 179 bp fragments) was nearly identical to the field cockroach (370 and 178 bp fragments). The CO1 amplicon (517 bp) differentiated German and field cockroaches but not Asian and field cockroaches. The CO1/TL2 amplicons (1275 bp) digested with AluI clearly differentiated all three species. The Asian cockroach had a distinct 540 bp fragment, whereas the field cockroach had a 403 bp fragment and the German cockroach lacked both fragments. Intraspecific polymorphs for CO1/TL2 amplicons (1275 bp) were observed with the German cockroach only. Portions of the CO1 and TL2 genes were sequenced, revealing 76% identity among German, Asian, and field cockroaches. Sequence data also revealed that German and Asian cockroaches were more closely related to each other than to the field cockroach
Pruning biomass potential in Italy related to crop characteristics, agricultural practices and agro-climatic conditions
This work, developed under the EuroPruning Project, aims to look at relations between pruning biomass production and several factors related both to crop species and management. The aim is to find out mathematical relations that allow improvement of the biomass potential assessment. This is generally calculated using biomass production ratios. These ratios are variable due to the influence of several aspects. On the one hand there are crop characteristics—such as species, cultivar, and age—and on the other, crop management, which is often associated to local habits and conditions such as the training system, planting pattern, density, pruning methods, irrigation and climate. This work has been produced by gathering data from literature reviews and surveying. The subset of Italian records in the EuroPruning database consists of 70 records. Each record contains the biomass production ratio and eight agronomic variables. Additionally, a set of six climatic and agro-climatic groups of variables (in total 28 variables) have been added to each record. Moderate to good correlations have been found, especially with few climatic factors. As a result, two regression models are proposed for the evaluation of the vineyard and olive tree pruning biomass ratios for Italy, and applied to assess pruning biomass potential
Mechanized recovery of olive pruning residues: ash contamination and harvesting losses
Agricultural residues represent an important source of biomass for energy. Among the available biomass suitable for energy and available in Italy, pruning represents about the 20% of the total. About 1.184 million of hectares are planted with olive trees; the pruning residues coming from these plantations represent a wide source of biomass at National level. The authors tested six commercial pruning harvesters to determine harvesting losses and product contamination when recovering pruning residues. All harvesters used a mechanical pick-up to collect the residues and a shredder to reduce them into chips. Three different pick-up settings were tested and namely: 1 cm above ground level, manufacturer’s specification and 3 cm above ground level. Ash content in the shredded material was taken as a measure of contamination: the uncontaminated branch material collected directly from the trees had a value of 3.5%, whereas in shredded residues varied between 4.5% and over 5.5%, for the shortest and the longest distance between the pick-up and the soil surface, respectively. Harvesting losses were slightly, but significantly, related to pick-up setting, and mainly depended on machine type. Both machines have shown a good quality of the work performed and the results obtained indicates that the work phases could be simplified in order to reduce both the time of use and the harvesting costs
Integration of SRF and carbonization plant for small forestry farms
A continuous oxidative carbonization pilot unit, with a capacity of 50 kg/h,has been developed and builtby RE-CORD; reported performance data shows that the unit can produce high quality charcoal, suitable for BBQ, metallurgy of activated-carbon manufacturing, as well as biochar. Charcoal yield in excess of 24 wt% (dry) has been achieved, with a fixed carbon content higher than 85 wt% (dry). In this work,the up-scaled 250 kg/h demo plant has been designed, and the construction, operation and maintenancecosts estimated. It was assumed to feed the plant with a dedicated SRF of either poplar or robinia, which represents a very innovative and yet unexplored value chain. Performance data are reported along with economic evaluation of the whole chain. Results shows how aland management scheme based on SRF coupled to innovative small-scale biomass carbonization technology represents an appealing opportunity for business diversification in small and medium forestry enterprises
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