Regression models of ignition time versus moisture content for the litter of Mediterranean forest species

2006 ◽  
Vol 234 ◽  
pp. S123 ◽  
Author(s):  
A.P. Dimitrakopoulos ◽  
E.A. Samara ◽  
I.D. Mitsopoulos
Keyword(s):  
Moisture Content ◽  
Regression Models ◽  
Ignition Time ◽  
Mediterranean Forest ◽  
Forest Species

Adaptation of Mediterranean forest species to climate: lessons from common garden experiments

2021 ◽  
Author(s):  
JA Ramírez‐Valiente ◽  
L Santos del Blanco ◽  
R Alía ◽  
JJ Robledo‐Arnuncio ◽  
J Climent
Keyword(s):  
Common Garden ◽  
Mediterranean Forest ◽  
Forest Species ◽  
Common Garden Experiments

Experimental study of moisture content effects on horizontal flame spread over thin cotton fabric

2018 ◽  
Vol 89 (15) ◽  
pp. 3189-3200 ◽  
Author(s):  
Yunji Gao ◽  
Guoqing Zhu ◽  
Hui Zhu ◽  
Weiguang An ◽  
Yu Xia
Keyword(s):  
Moisture Content ◽  
Cotton Fabric ◽  
Flame Spread ◽  
Extreme Values ◽  
Ignition Time ◽  
Convective Heat Transfer Coefficient ◽  
Flame Height ◽  
Spread Rate ◽  
Untreated Cotton ◽  
Flame Spread Rate

In this paper, moisture content effects on horizontal flame spread were experimentally investigated using 0.245 mm thick, 28 cm tall and 28 cm wide untreated cotton fabric sheets with various moisture contents varying from 0 to 34%. The pyrolysis spread rates, flame heights and ignition times were obtained and analyzed. The corresponding results are as follows: as moisture content increases, the flame height and spread rate first increase and then decrease. In contrast, the ignition time shows an opposite trend with moisture content. The extreme values are observed in cases of 2% moisture content samples. Moreover, the flame spread rate in the warp direction is larger than that in the weft direction. For horizontal flame spread, the moisture content has the effect of consuming part of the heat feedback, which can play a role in reducing the flame spread rate; simultaneously, the moisture content can enlarge flame size and increase the convective heat transfer coefficient, thereby resulting in an increase in flame spread rate. The non-monotonous trend in pyrolysis spread rate is the result of competition between these effects.

scholarly journals Characteristics of Woody Cutting Waste Briquette with Paper Waste Pulp as Binder

2020 ◽  
Vol 190 ◽  
pp. 00030
Author(s):  
Qurrotin Ayunina Maulida Okta Arifianti ◽  
Azmi Alvian Gabriel ◽  
Syarif Hidayatulloh ◽  
Kuntum Khoiro Ummatin
Keyword(s):  
Moisture Content ◽  
Ignition Time ◽  
Combustion Process ◽  
Calorific Value ◽  
Volatile Matter ◽  
Proximate Analysis ◽  
Hydraulic Press ◽  
Combustion Characteristic ◽  
Paper Waste ◽  
Iron Mold

The current research aimed to increase the calorific value of woody cutting waste briquette with paper waste pulp as binder. There were three different binder variation used in this study, they are 5 %, 10 %, and 15 %. To create a briquette, a cylindrical iron mold with diameter of 3.5 cm and height of 3 cm and a hydraulic press with 2 t power were applied. The physical characteristics of the combination woody waste briquette and paper waste pulp, such as moisture content, ash content, volatile matter and carbon fix were examined using proximate analysis. The calorific value of briquetted fuel was tested by bomb calorimeter. The combustion test was performed to determine the combustion characteristic of briquettes, for example initial ignition time, temperature distribution, and combustion process duration. The general result shows that the calorific value of briquette stood in the range of 4 876 kCal kg–1 to 4 993 kCal kg–1. The maximum moisture content of briquette was 5.32 %. The longest burning time was 105 min.

scholarly journals Processing of Wild Sunflower with Different Moisture Contents into Solid Bio Fuel

2021 ◽  
pp. 1-9
Author(s):  
Fabie T. Dummapi ◽  
Jacqueline I. Liniasan ◽  
Marvin T. Valentin ◽  
Milagros B. Onalan ◽  
Leonardo D. Dumalhin ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Moisture Content ◽  
Physical Properties ◽  
Ignition Time ◽  
Volume Density ◽  
Ash Content ◽  
Burning Time ◽  
Wild Sunflower ◽  
Average Mass ◽  
Moisture Contents

Wild sunflower with moisture contents of 16%, 12% and 8% was densified without the addition of binding agent. The physical properties of the formed briquettes such as mass, dimensions, volume, density and shattering resistance were evaluated. Thermal properties like ignition time, burning time, ash content, and thermal fuel efficiency by means of boiling test were also evaluated. Wild Sunflower stems were gathered and shredded using locally fabricated biomass shredder available at the Research Office of Benguet State University, and were processed into the desired size and moisture contents. Right after the briquetting operation, the physical properties of the briquette were measured and then stored in a zip bag for 24 hours. After the storage, same measurement was conducted. Results show that the influence of moisture contents on the average mass, dimension, shattering resistance, volume and density was statistically insignificant. The wild sunflower with moisture content of 16% had the highest shattering resistance of 88.85%. Furthermore, the influence of moisture content on the thermal properties like ignition time, burning time and ash content are statistically insignificant. Among the moisture contents, the fastest ignition time of 43.75 sec with longest burning time was recorded under 12%. Ash content was also lowest at 12%.

scholarly journals CARS Algorithm-Based Detection of Wheat Moisture Content before Harvest

Symmetry ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 115
Author(s):  
Hong Ji ◽  
Wanzhang Wang ◽  
Dongfeng Chong ◽  
Boyang Zhang
Keyword(s):  
Moisture Content ◽  
Regression Model ◽  
Regression Models ◽  
Partial Least Squares Regression ◽  
Early Stage ◽  
Least Squares Regression ◽  
Calibration Sample ◽  
Non Destructive ◽  
Plsr Model ◽  
Variable Subset

To rapidly detect the wheat moisture content (WMC) without harm to the wheat and before harvest, this paper measured wheat and panicle moisture content (PMC) and the corresponding spectral reflectance of panicle before harvest at the Beijing Tongzhou experimental station of China Agricultural University. Firstly, we used correlation analysis to determine the optimal regression model of WMC and PMC. Secondly, we derived the spectral sensitive band of PMC before filtering the redundant variables competitive adaptive reweighted sampling (CARS) to select the variable subset with the least error. Finally, partial least squares regression (PLSR) was used to build and analyze the prediction model of PMC. At the early stage of wheat harvest, a high correlation existed between WMC and PMC. Among all regression models such as exponential, univariate linear, polynomial models, and the power function regression model, the logarithm regression model was the best. The determination coefficients of the modeling sample were: R2 = 0.9284, the significance F = 362.957, the determination coefficient of calibration sample R2v = 0.987, the root mean square error RMSEv = 3.859, and the relative error REv = 7.532. Within the range of 350–2500 nm, bands of 728–907 nm, 1407–1809 nm, and 1940–2459 nm had a correlation coefficient of PMC and wavelength reflectivity higher than 0.6. This paper used the CARS algorithm to optimize the variables and obtained the best variable subset, which included 30 wavelength variables. The PLSR model was established based on 30 variables optimized by the CARS algorithm. Compared with the all-sensitive band, which had 1103 variables, the PLSR model not only reduced the number of variables by 1073, but also had a higher accuracy in terms of prediction. The results showed that: RMSEC = 0.9301, R2c = 0.995, RMSEP = 2.676, R2p = 0.945, and RPD = 3.362, indicating that the CARS algorithm could effectively remove the variables of spectral redundant information. The CARS algorithm provided a new way of thinking for the non-destructive and rapid detection of WMC before harvest.

scholarly journals Preference by Donkeys and Goats among Five Mediterranean Forest Species: Implications for Reducing Fire Hazard

Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1302
Author(s):  
Jordi Bartolomé ◽  
Jordi Miró ◽  
Xavier Panadès ◽  
Maria José Broncano ◽  
Josefina Plaixats ◽  
...  
Keyword(s):  
Forest Fires ◽  
Pinus Halepensis ◽  
Fire Hazard ◽  
Mediterranean Forest ◽  
Mediterranean Forests ◽  
Forest Species ◽  
Rubus Ulmifolius ◽  
Key Species ◽  
The Mediterranean ◽  
Cafeteria Test

During the second half of the 20th century, European countries experienced an increase in their forest area due to the global change. Consequently, there has been an increase in large forest fires, mainly in the Mediterranean basin, and this has forced the development of several types of prevention programs. One of them is the control of the understory by livestock. In this sense, browsing with a combination of donkeys and goats could be a good option, as both animals usually feed on forest species. However, little is known about their preferences for the key species of the Mediterranean forest. Using a cafeteria test, the preferences and consumption of both animals have been determined for five typical species of the Mediterranean forest, such as Quercus ilex, Pinus halepensis, Phillyrea latifolia, Rubus ulmifolius, and Brachypodium retusum. Results showed that donkeys and goats could act complementarily in the reduction of the fuel biomass of forests. Donkeys appear to act more on fine fuel, such as B. retusum, and goats on the more pyrophyte species, in this case P. halepensis. In addition, given that donkeys are at severe risk of extinction in Europe, this role of providing ecosystem services could contribute to their conservation. Despite this study only showing that goats and donkeys would consume all five presented plant species and that there are some differences in consumption during a short-term test, it constitutes a useful first step for conservation and fire prevention in the Mediterranean forests.

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