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Calibrating and validating AquaCrop model for maize crop in Northern zone of Nigeria CIGR Journal
Ezekiel, Oiganji; Igbadun, H. E.; Mudiare, O.J.; Oyebode, M.A..
Farmers in the northern Guinea Savannah ecological zone of Nigeria have been experiencing declining crop yield due to erratic water supply. In recent times, research on better water management and interaction between effects of climate, soil and field management on crop production is fast gaining grounds with the use of models. Models can be used to predict the impact of long-term climate variability, thus providing an opportunity of better techniques compared with the traditional multi-location trials. This study presents the calibration and validation of AquaCrop model for drip irrigated maize (Zea mays). Calibration was done using data of 2013, while validation across seasons was done with data of 2014. The modelling efficiency of grain yield, biomass...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural Engineering/ soil and water conservation engineering growth stage; Deficit irrigation; Drip irrigation; Water management; Modelling.
Ano: 2016 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3755
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Calibration and study of soil physical-hydric relations using a frequency domain reflectometry probe CIGR Journal
Duarte, Thiago; Silva, Tonny José Araújo da; Bonfim-Silva, Edna Maria; Souza, Hanna Pricilla Barbosa.
The FDR Diviner 2000® probe is widely used to monitor soil moisture and to study physical-hidric relationships. The calibration equation provided by the manufacturer may not correctly reproduce the actual moisture value for the same type of soil with different bulk densities. In addition, it was postulated in this experiment that the capacitance probe can be used to determine the soil water tension and the initial soil water retention curve. Thus, the objectives were: to assess whether the calibration equation parameters of the FDR probe changes with the bulk density variation; estimate the soil water tension using the FDR probe; and verify the effect of the probe calibration in determining the initial soil water retention curve for the Red Oxisol at three...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Soil physics; Soil moisture; Soil compaction; Instrumentation; Diviner 2000®..
Ano: 2021 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/6673
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Calibration and validation of the aquacrop model for the culture lettuce (lactuca sativa l.) under fertilization levels in pluvial condition CIGR Journal
Amirouche, mawhoub.
The search for decision-making tools is essential in order to control agricultural practices and plan for sustainable agriculture that respects the environment. To this end, FAO has developed an evaluation model called AquaCrop, which covers most technical routes, including fertilization. In this perspective, this study focuses on the AquaCrop model (v6.1) to calibrate it for the simulation of lettuce crop yields (Lactuca sativa L), under different fertilization levels for the trial periods (2015/2016) and (2016/2017). Four levels of fertilization were examined under rain conditions, namely T1 (0 kg N/ha), T2 (60 kg N/ha), T3 (120 kg N/ha) and T4 (180 kg N/ha). The model performance was evaluated using the coefficient of determination (R2), the square root...
Tipo: Info:eu-repo/semantics/article Palavras-chave: AquaCrop; Lettuce; Calibration; Validation; Fertility stress; Water productivity.
Ano: 2021 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/6195
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Cap-hardening parameters of Cam-clay model variations with soil moisture content and shape-restricted regression model CIGR Journal
Mehari Zewde Tekeste; Deere&Co; Desale H Habtzghi; Department of Statistics, The University of Akron, Akron, OH; Jos Koolen; Wagenigen University.
Modeling of soil elastic and permanent plastic volumetric strains (compaction) caused by loading from machinery vehicles using the modified Cam-clay soil constitutive model requires understanding the behaviors of compression and rebound parameters under unsaturated soil conditions.  Oedometer tests were conducted on a sandy loam, a loam, and a clay loam soil, all tropical soils, at three initial soil moisture contents and five maximum stress levels (50, 100, 200, 300 and 400 kPa).  The objectives were to investigate the effects of soil moisture content and maximum applied stress on the modified compression index (l*) and modified rebound index (k*) parameters of a modified Cam-clay soil model on the three soils and predict the compressibility indices using...
Palavras-chave: Modified compression index (l*); Modified rebound index (k*); Axial stress; Uniaxial compression cyclic test; Soil moisture; Soil types.
Ano: 2013 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2214
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Carbon Dioxide Production in Animal Houses: A Literature Review CIGR Journal
S. Pedersen; V. Blanes-Vidal; H. Joergensen; A. Chwalibog; A. Haeussermann; M. J. W. Heetkamp; A.J.A. Aarnink.
This article deals with carbon dioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbon dioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from animal houses). The investigations include measurements in respiration chambers and in animal houses, mainly for growing pigs and broilers.Over the last decade a fixed carbon dioxide production of 185 litres per hour per heat production unit, hpu (i.e. 1000 W of the total animal heat production at 20 oC) has often been used. The article shows that the carbon dioxide production per hpu increases with increasing respiration quotient. As the respiration quotient...
Ano: 1969 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/1205
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Case study about field trial responses of the zero energy storage system CIGR Journal
Islam, M. P.; Morimoto, T.; Hatou, K.; Hassan, L.; Awal, M. A.; Hossain, S. T..
A low cost ‘Zero Energy Cool Chamber (ZECC)’ has been developed for storing fruits and vegetables by usingpassive evaporative mechanism. This paper presents the results of a survey on the farmer’s opinion regarding the exploitationof zero energy storage system. This survey was conducted at Mymensingh district of Bangladesh from 2011 to 2012 and italso revealed that most of the farmers sell their produce to the middlemen just after the harvest. Lack of transportation facility, shortage of energy supply and lack of investment on storage, lower price of vegetables during the harvesting season, farmers in the rural areas often sell their products to the middleman or in the local market at low prices. They are not even able to get the return of invested money...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural produces; Storage; Farmer’s perception; Quality; Benefit; Bangladesh.
Ano: 2013 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2534
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CFD and experimental analysis of direct solar dryer for fish CIGR Journal
Obayopo, Surajudeen Olanrewaju; Oluwasanmi, Alonge.
 Fish preservation is the most important post-harvest process in commercial fishery. The traditional methods of fish preservation are inefficient and susceptible to contamination. Few existing solar fish dryers are not designed for optimal drying performance. In this study, a direct solar dryer for fish was numerically modelled, fabricated and evaluated for performance enhancement. The modeling was performed using computational fluid dynamics (CFD) code to simulate different dimensions of the designed dryer at varying fan speeds. By applying desirability function method, (70 × 60 × 40) cm3 drying chamber with a plane of 25 cm away from the base for tray location gives optimal temperature and the best uniform air flow distribution. The performance of the...
Tipo: Info:eu-repo/semantics/article
Ano: 2019 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5051
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CFD Model of Regenerative Heat Exchanger CIGR Journal
Kic, Pavel.
This paper is focused on the Computational fluid dynamics (CFD) modeling of regenerative heat exchanger suitable for animal houses. Buildings used for housing of animals in farms with intensive breeding, like poultry or pig houses, are characterized by high generation of heat inside, partly produced by animals, and in the case of small young animals, supplemented also by heating. On the other side these buildings need intensive ventilation which causes big losses of energy by exhausted air. A good way how to reduce heat losses can be the use of technical systems of heat recovery. There are two principal constructions of heat exchangers for heat recovery. There are either recuperative or regenerative heat exchangers. Industrially produced heat exchangers,...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Animal houses; Ventilation; Energy; Parameters; Czech Republic.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3137
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CFD Model of Regenerative Heat Exchanger CIGR Journal
Pavel Kic.
This paper is focused on the Computational fluid dynamics (CFD) modeling of regenerative heat exchanger suitable for animal houses. Buildings used for housing of animals in farms with intensive breeding, like poultry or pig houses, are characterized by high generation of heat inside, partly produced by animals, and in the case of small young animals, supplemented also by heating. On the other side these buildings need intensive ventilation which causes big losses of energy by exhausted air. A good way how to reduce heat losses can be the use of technical systems of heat recovery. There are two principal constructions of heat exchangers for heat recovery. There are either recuperative or regenerative heat exchangers. Industrially produced heat exchangers,...
Palavras-chave: Animal houses; Ventilation; Energy; Parameters; Czech Republic.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3137
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Chamber measurement methods and aeration effect on greenhouse gas fluxes during composting CIGR Journal
Kyu-Hyun Park; Ngwa Martin Ngwabie; University of Guelph; Claudia Wagner-Riddle.
Composting has the potential to mitigate methane (CH4) and nitrous oxide (N2O) emissions from manure.  The heterogeneous nature of emitting surfaces makes it difficult to quantify these emissions.  CH4 and N2O fluxes measured using eight small chambers (0.72 m2) and a mega chamber (90 m2) were compared, and the effect of aeration on the fluxes during composting was studied.  Two batches of compost were placed in three channels and 2-3 small flux chambers were deployed on each channel.  The channels were enclosed by a building serving as a mega chamber.  Chamber location significantly affected gas fluxes, pointing to strong spatial heterogeneity.  Mean CH4 fluxes from the small chambers were similar or...
Palavras-chave: Chamber; Compost; Greenhouse gases; Aeration; Flux.
Ano: 2014 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2467
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Chamber measurement methods and aeration effect on greenhouse gas fluxes during composting CIGR Journal
Park, Kyu-Hyun; Ngwabie, Ngwa Martin; Wagner-Riddle, Claudia.
Composting has the potential to mitigate methane (CH4) and nitrous oxide (N2O) emissions from manure.  The heterogeneous nature of emitting surfaces makes it difficult to quantify these emissions.  CH4 and N2O fluxes measured using eight small chambers (0.72 m2) and a mega chamber (90 m2) were compared, and the effect of aeration on the fluxes during composting was studied.  Two batches of compost were placed in three channels and 2-3 small flux chambers were deployed on each channel.  The channels were enclosed by a building serving as a mega chamber.  Chamber location significantly affected gas fluxes, pointing to strong spatial heterogeneity.  Mean CH4 fluxes from the small chambers were similar or 1.4 times higher compared to the mega chamber.  Mean...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chamber; Compost; Greenhouse gases; Aeration; Flux.
Ano: 2014 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2467
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Changes and prospects for rice processing at the Niger Office in Mali CIGR Journal
Yacouba Mamadou, COULIBALY; Michel, HAVARD.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Socio economics; Post harvest technology Rice; Processing; Rice; Stakeholders; Profitability; Competitiveness; Mali.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3017
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Characterisation of Small Scale Feed Mills in a Developing Country CIGR Journal
Adetifa, Babatunde Olusola; Okewole, Oyewole Titilope.
There are many cottage scale animal farms in Nigeria that are sustained by the existence of small scale feed mills. The growth of these small scale feed mills is affected by some problems. A study to investigate some of the technical problems in small scale feed mills was conducted using Ibadan, Oyo State, Nigeria as a case study. Ten feed mills were randomly selected and investigated while thirty workers were assessed. The characteristics of the feed mills were investigated in terms of capacity, number of workers, mill operations and equipment used and the problems were investigated by studying four different areas which include; power source; unit operations/equipment; energy utilization pattern and workplace safety/hygiene. A questionnaire was designed...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural Engineering; Agricultural Processing; Feed milling; Management Capacity Energy use Grower’s mash Hygiene Layer’s mash Power source Unit operations.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3012
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Characteristics of Floors for Pig Pens: Friction, Shock Absorption, Ammonia Emission and Heat Conduction CIGR Journal
S. Pedersen; P. Ravn.
In respect to improving animal welfare and to minimize the ammonia emission from animal facili-ties, it is important to have appropriate information on the impact of the flooring system in pig pens. Twelve different floors, six commercially available and six experimental floors for pig pens, were investigated in respect to four different characteristics: friction coefficients, shock absorption, am-monia emission and heat conduction. The friction coefficients were measured as dynamic friction for dry floors and floors wetted with water and rapeseed oil and as static friction for dry floors. The floor elasticity was measured as shock absorption when letting a weight fall on the test floors. The ammonia emission was measured in a wind tunnel with ammonia...
Ano: 1969 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/1202
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Characteristics of locally fabricated sugarcane grab loaders related to transport CIGR Journal
Abdel-Mawla, Hassan Abdel-Razek.
AbstractManual loading of sugarcane is expensive slow operation last for several hours, therefore, mechanical loading have been urgently required.  To overcome the problem of the astronomical prices of self propelled sugarcane loaders, the tractor attached sugarcane loader were designed and locally fabricated.  The constructive and functional parameters of front loaders mounted on agricultural wheel tractors have to satisfy the requirements of the working process and of the dynamic stability and have to correspond to the structures of the tractors they are mounted on.   The current article aimed to study the geometry loader/vehicle relationship while loading and transporting sugarcane.   Vehicles equipped for sugarcane transport include rail transport...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Sugarcane loading; Sugarcane loaders; Sugarcane transport vehicles; Loader design; Loader/vehicle relashionship; Loader/vehicle geometry.
Ano: 2016 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3779
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Characterization and Evaluation of the Mechanical and Physical properties of Tef stem (Eragrostistef (Zucc.)Trotter) CIGR Journal
gelaw, geta kidanemarim; Tilahun, Daniel; Zegeye, Adamu.
Tef (Eragrostistef (Zucc.)Trotter) is atypical crop growing in most areas of Ethiopia, with the first area coverage. In this study mechanical properties of Tef stem the major four varieties, viz;  Local, Dz-Cr-438- (Kora), Dz-Cr-387/RIL-355(Quncho) and Dz-01-1880 (Guduru) was determined. The factors considered were moisture content, diameter and thickness of the Tef stem and analyze their mechanical properties using Texture Analyzer and Universal Testing Machine. The result indicated that the minimum and maximum value of modulus of elasticity was 0.13 and 2.6 Gpa at  moisture level 8.82% and 16.6%; 1.03 and 3.6Gpa at moisture level 10.32% and 13.79%; 0.85 and 3.22Gpa  at moisture level 7.65% and 12.72%; 1.27 and 3.88Gpa at moisture  level 5.5% and 19.70%...
Tipo: Info:eu-repo/semantics/article Palavras-chave: PhD candidate and Asociate professors Modulus of elasticity; Flexural rigidity; Shear stress; Tef stem; Variety.
Ano: 2019 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5112
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Characterization of brewery waste water and evaluation of its potential for biogas production CIGR Journal
Murunga, Sylvia Injete; Mbuge, Duncan Onyango; Gitau, Ayub Njoroge; Mutwiwa, Urbanus Ndungwa; Wekesa, Ingrid Namae.
The issue of global warming and climate change is strongly receiving public attention and has become a major environmental concern both nationally and internationally. Brewing industries are among the largest consumers of water and the largest source of organic effluent mostly from the brewing, cleaning, and cooling processes which must be treated to allowable levels to reduce environmental pollution. Close to 10 L water is used for every 1 L beer that is brewed, though the amount of water in the final beer is small. A study was undertaken to characterize and assess the variations in the quality of untreated brewery waste water. Samples from different process streams including brewing line, clean in place line and mixing line from two brewing industries in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Brewery; Physicochemical characterization; Waste water; Pollution; Biodegradable; Anaerobic digestion.
Ano: 2016 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3759
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CHARACTERIZATION OF CONVENTIONAL COOKING STOVES IN SOUTH EASTERN NIGERIA CIGR Journal
Segun, Bello Raphael.
Abstract   Performance characterization of some selected conventional cook stoves in South Eastern Nigeria had been carried out. Three conventional cook stoves (3-stone stove, charcoal stove and sawdust stove) were selected and evaluated. Their performances were compared with those of improved stove. The results show that the time spent in cooking 1 Kg of rice/(yam) is significantly different in all the conventional stoves under test; (maximum 0.75 (0.44) kg/hr for 3-stone stove and minimum 0.61 (0.35) hr/kg for charcoal). Fuel utilization also differs for instance lesser quantity of charcoal would be required to cook the same quantity of food on the charcoal stove than the open fire stove. Also the specific fuel consumption value of charcoal stove is...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Wood products & Machinery Cook stove; Fuel consumption; Thermal efficiency; Burn rate.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3037
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Characterization of Torrefied Biomass Pellets from Agricultural Residues for Solid Fuels CIGR Journal
HOMDOUNG, NIGRAN.
Torrefaction and densification are suitable techniques for upgrading solid biomass materials. They can improve the energy properties of solid fuels. The objective of this research was to evaluate changes in physico-chemical properties of agricultural residues (corn-cobs and rice husks) during torrefaction. Physical properties of the torrefied biomass pellets were analysed. The results showed that increasing the torrefaction temperature and time resulted in reduced moisture and volatile matter content of corn-cobs and rice husks. At the same time, fixed carbon, ash content and heating values were increased. The heating values of both torrefied fuels were in the range of 14.9–16.9 MJ/kg, increased by about 16 to 22% from the raw biomass. The optimum...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural residues; Torrefaction; Densification; Torrefied biomass; Solid fuels.
Ano: 2020 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5741
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Chemical Oxygen Demand removal rate comparative analysis using three different biogas digesters CIGR Journal
Nwaigwe, Kevin Nnanye; Ononogbo, Chibuike; Anyanwu, Emmanuel E; Enweremadu, Christopher C.
The Chemical Oxygen Demand (COD) end value of effluent discharged from a bioreactor into the environment is a critical indicator of its capacity to pollute the environment. A comparative parametric analysis of COD removal rate using three different biogas digesters is presented.  The three bioreactors are Upflow Anaerobic Sludge Blanket (UASB), Upflow Bioreactor with Central Substrate Dispenser (UBCSD), and Continuous Stirred-Tank Reactor (CSTR). In order to select the most fitting bioreactor type among the three considered, experimentation was carried out using organic municipal waste (OMW) as substrate. A 10-day hydraulic retention time (HRT) was used, while cattle rumen microbes were used to improve digestion rate. UBCSD showed the highest level of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Renewable Energy and Environmental Engineering Chemical Oxygen Demand; Biogas digesters; Parametric analysis; Hydraulic retention time..
Ano: 2017 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/4117
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