Search results for: culm height

Authors: Yeo Kyeong Lee, Ji Yeon Kang, Eun Mi Ryu, Hee Sun Kim, Yeong Soo Shin

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The objective of this paper is an investigation of the effects of the thickness and axial loading during a fire test on the load-bearing capacity of a fire-damaged normal-strength concrete wall. Two factors are attributed to the temperature distributions in the concrete members and are mainly obtained through numerous experiments. Toward this goal, three wall specimens of different thicknesses are heated for 2 h according to the ISO-standard heating curve, and the temperature distributions through the thicknesses are measured using thermocouples. In addition, two wall specimens are heated for 2 h while simultaneously being subjected to a constant axial loading at their top sections. The test results show that the temperature distribution during the fire test depends on wall thickness and axial load during the fire test. After the fire tests, the specimens are cured for one month, followed by the loading testing. The heated specimens are compared with three unheated specimens to investigate the residual load-bearing capacities. The fire-damaged walls show a minor difference of the load-bearing capacity regarding the axial loading, whereas a significant difference became evident regarding the wall thickness. To validate the experiment results, finite element models are generated for which the material properties that are obtained for the experiment are subject to elevated temperatures, and the analytical results show sound agreements with the experiment results. The analytical method based on validated thought experimental results is applied to generate the fire-damaged walls with 2,800 mm high considering the buckling effect: typical story height of residual buildings in Korea. The models for structural analyses generated to deformation shape after thermal analysis. The load-bearing capacity of the fire-damaged walls with pin supports at both ends does not significantly depend on the wall thickness, the reason for it is restraint of pinned ends. The difference of the load-bearing capacity of fire-damaged walls as axial load during the fire is within approximately 5 %.

Keywords: normal-strength concrete wall, wall thickness, axial-load ratio, slenderness ratio, fire test, residual strength, finite element analysis

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Authors: Enrique González Pendás, Vidal Pérez Hernández, Jorge Ferro Díaz, Nelson Careaga Pendás

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The investigation is carried out on the Protected Area of San Ubaldo, toward the interior of an open pinegrove with palm trees in a dry plainness of quar zitic sands, belonging to the Floristic Managed Reservation San Ubaldo-Sabanalamar, Guane, Pinar del Río, Cuba. This area is characterized by drastic seasonal variations, high temperatures and water evaporation, strong solar radiation, with sandy soils of almost pure quartz, which are very acid and poor in nutrients. The objective of the present work is to determine evidence of facilitation and its relationship with the structure and composition of plant communities in these peculiar ecosystems. For this study six lineal parallel transepts of 100 m are traced, in those, a general recording of the flora is carried out. To establish which plants act as nurses, is taken into account a height over 1 meter, canopy over 1.5 meter and the occurrence of several species under it. Covering was recorded using the line intercept method; the medium values of species richness for the taxa under nurses is compared with those that are located in open spaces among them. Then, it is determined which plants are better recruiter of other species (better nurses). An experiment is made to measure and compare some parameters in pine seedlings under the canopy of the Byrsonima crassifolia (L.) Kunth. and in open spaces, also the number of individuals is counted by species to calculate the frequency and total abundance in the study area. As a result, it is offered an up-to-date floristic list, a phylogenetic tree of the plant community showing a high phylodiversity, it is proven that the medium values of species richness and abundance of species under the nurses, is significantly superior to those occurring in open spaces. Furthermore, by means of phylogenetic trees it is shown that the species which cohabit under the nurses are not phylogenetically related. The former results are cited evidences of facilitation among plants, as well as it is one more time shown the importance of the nurse effect in preserving plant diversity on extreme environments.

Keywords: facilitation, nurse plants, positive interactions, quarzitic sands

Procedia PDF Downloads 322

Authors: Abbas Kamalibandpey, Alain Beland, Joseph Mukendi Kabuya

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Since a rock mass is a discontinuum medium, its behaviour is governed by discontinuities such as faults, joint sets, lithologic contact, and bedding planes. Thus, rock slope stability analysis in jointed rock masses is largely dependent upon discontinuities constitutive equations. This paper studies the difference between the Mohr-Coulomb (MC) and the Barton-Bandis (BB) joint constitutive numerical models for lithological contacts and joint sets. For the rock in these models, generalized Hoek-Brown criteria have been considered. The joint roughness coefficient (JRC) and the joint wall compressive strength (JCS) are vital parameters in the BB model. The numerical models are applied to the rock slope stability analysis in the Mont-Wright (MW) mine. The Mont-Wright mine is owned and operated by ArcelorMittal Mining Canada (AMMC), one of the largest iron-ore open pit operations in Canada. In this regard, one of the high walls of the mine has been selected to undergo slope stability analysis with RS2D software, finite element method. Three piezometers have been installed in this zone to record pore water pressure and it is monitored by radar. In this zone, the AMP-IF and QRMS-IF contacts and very persistent and altered joint sets in IF control the rock slope behaviour. The height of the slope is more than 250 m and consists of different lithologies such as AMP, IF, GN, QRMS, and QR. To apply the B-B model, the joint sets and geological contacts have been scanned by Maptek, and their JRC has been calculated by different methods. The numerical studies reveal that the JRC of geological contacts, AMP-IF and QRMS-IF, and joint sets in IF had a significant influence on the safety factor. After evaluating the results of rock slope stability analysis and the radar data, the B-B constitutive equation for discontinuities has shown acceptable results to the real condition in the mine. It should be noted that the difference in safety factors in MC and BB joint constitutive models in some cases is more than 30%.

Keywords: barton-Bandis criterion, Hoek-brown and Mohr-Coulomb criteria, open pit, slope stability

Procedia PDF Downloads 74

Authors: Yun Chen, Qihang Liu, Catherine Ticehurst, Chandrama Sarker, Fazlul Karim, Dave Penton, Ashmita Sengupta

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The application of ICESAT-2 altimetry data in river hydrology critically depends on the accuracy of the mean water surface elevation (WSE) at a virtual station (VS) where satellite observations intersect with water. The ICESAT-2 track generates multiple VSs as it crosses the different water bodies. The difficulties are particularly pronounced in large river basins where there are many tributaries and meanders often adjacent to each other. One challenge is to split photon segments along a beam to accurately partition them to extract only the true representative water height for individual elements. As far as we can establish, there is no automated procedure to make this distinction. Earlier studies have relied on human intervention or river masks. Both approaches are unsatisfactory solutions where the number of intersections is large, and river width/extent changes over time. We describe here an automated approach called “auto-segmentation”. The accuracy of our method was assessed by comparison with river water level observations at 10 different stations on 37 different dates along the Lower Murray River, Australia. The congruence is very high and without detectable bias. In addition, we compared different outlier removal methods on the mean WSE calculation at VSs post the auto-segmentation process. All four outlier removal methods perform almost equally well with the same R2 value (0.998) and only subtle variations in RMSE (0.181–0.189m) and MAE (0.130–0.142m). Overall, the auto-segmentation method developed here is an effective and efficient approach to deriving accurate mean WSE at river VSs. It provides a much better way of facilitating the application of ICESAT-2 ATL13 altimetry to rivers compared to previously reported studies. Therefore, the findings of our study will make a significant contribution towards the retrieval of hydraulic parameters, such as water surface slope along the river, water depth at cross sections, and river channel bathymetry for calculating flow velocity and discharge from remotely sensed imagery at large spatial scales.

Keywords: lidar sensor, virtual station, cross section, mean water surface elevation, beam/track segmentation

Procedia PDF Downloads 35

Authors: T. Wen, Y. Liu, J. Wang, W. Zheng, T. Shao

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Along with the increasing density of urban population, solar energy potential of building facade in high-density residential areas become a question that needs to be addressed. This paper studies how the solar energy utilization potential of building facades in different locations of a residential areas changes with different building layouts and orientations in Xining, a typical city in west China which possesses large solar radiation resource. Solar energy potential of three typical building layouts of residential areas, which are parallel determinant, gable misalignment, transverse misalignment, are discussed in detail. First of all, through the data collection and statistics of Xining new residential area, the most representative building parameters are extracted, including building layout, building height, building layers, and building shape. Secondly, according to the results of building parameters extraction, a general model is established and analyzed with rhinoceros 6.0 and its own plug-in grasshopper. Finally, results of the various simulations and data analyses are presented in a visualized way. The results show that there are great differences in the solar energy potential of building facades in different locations of residential areas under three typical building layouts. Generally speaking, the solar energy potential of the west peripheral location is the largest, followed by the East peripheral location, and the middle location is the smallest. When the deflection angle is the same, the solar energy potential shows the result that the West deflection is greater than the East deflection. In addition, the optimal building azimuth range under these three typical building layouts is obtained. Within this range, the solar energy potential of the residential area can always maintain a high level. Beyond this range, the solar energy potential drops sharply. Finally, it is found that when the solar energy potential is maximum, the deflection angle is not positive south, but 5 °or 15°south by west. The results of this study can provide decision analysis basis for residential design of Xining city to improve solar energy utilization potential and provide a reference for solar energy utilization design of urban residential buildings in other similar areas.

Keywords: building facade, solar energy potential, solar radiation, urban residential area, visualization, Xining city

Procedia PDF Downloads 154

Authors: Arunas Emeljanovas, Brigita Mieziene, Tomas Venckunas

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Background statement: Level of aerobic capacity in school age children provides important information about the current and future cardiovascular, skeletal and mental health. It is widely recognised that risk factors for modern chronic diseases of the adults have their origins in childhood and adolescence. The aim of the study was to analyse the trends of aerobic capacity across decades within groups of gender and age. Methods. The research included data of participants from the three nationally representative cohort studies performed in Lithuania in the years 1992, 2002 and 2012 among 11 to 18-years-old school children. Total of 18,294 school children were recruited for testing. Only those who had their body weight and height measured and completed 20 m shuttle endurance test were included in the analysis. The total number of students included in the analyses was 15,213 (7608 boys and 7605 girls). The permission to conduct the study was obtained from the Lithuanian Bioethics Committee (permission number BE-2-45). Major findings: Results are performed across gender and age groups. The comparison of shuttle endurance test, controlling for body mass index, indicated that in general there is a constant decrease of aerobic capacity across decades in both genders and age groups. The deterioration in aerobic capacity in boys accounted for 17 to 43 percent across age groups within decades. The biggest decrease was in 14 years-old boys. The deterioration in girls accounted for 19 to 37 percent across age groups with the highest decrease in 11 years-old girls. Though, girls had lower levels of aerobic capacity through all age groups and across three decades. Body mass index, as a covariate, accounted for up to six percent in deterioration of aerobic capacity. Final statement: The detected relationships may reflect the level and pattern of engagement in physical activity and sports where increased activity associates with superior performance in the tests because of the upregulated physiological function and instigated competitive/motivational level. The significance of the decade indirectly supports the importance of the recently changed activity among schoolchildren for this relationship.

Keywords: aerobic capacity, cardiovascular health, endurance, school age children

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Authors: Thimma Reddy Pothireddy, Ramesh Srikonda

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India is prone to natural disasters such as Floods, droughts, cyclones, earthquakes and landslides frequently due to its geographical considerations. It has become a persistent phenomenon as observed in last ten decades. The recent survey indicates that about 60% of the landmass is prone to earthquakes of various intensities with reference to Richard scale, over 40 million hectares is prone to floods; about 8% of the total area is prone to cyclones and 68% of the area is vulnerable to drought. Climate change is likely to be perceived through the experience of extreme weather events. There is growing societal concern about climate change, given the potential impacts of associated natural hazards such as cyclones, flooding, earthquakes, landslides etc. The recent natural calamities such as Cyclone Hudhud had crossed the land at Northern cost of AP, Vishakapatanam on 12 Oct’2014 with a wind speed ranging between 175 – 200 kmph and the records show that the tidal waves were reached to the height of 14mts and above; and it alarms us to have critical focus on planning issues so as to find appropriate solutions. The existing condition is effective is in terms of institutional set up along with responsive management mechanism of disaster mitigation but considerations at settlement planning level to allow mitigation operations are not adequate. This paper deals to understand the response to climate change will possibly happen through adaptation to climate hazards and essential to work out an appropriate mechanism and disaster receptive settlement planning for responding to natural (and climate-related) calamities particularly to cyclones and floods. The statistics indicate that 40 million hectares flood prone (5% of area), and 1853 kmts of cyclone prone coastal length in India so it is essential and crucial to have appropriate physical planning considerations to improve preparedness and to operate mitigation measures effectively to minimize the loss and damage. Vijayawada capital region which is susceptible to cyclonic and floods has been studied with respect to trajectory analysis to work out risk vulnerability and to integrated disaster mitigation physical planning considerations.

Keywords: meta analysis, vulnerability index, physical planning, trajectories

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Authors: Jonas Gradauskas, Oleksandr Masalskyi, Ihor Zharchenko

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The advancement in improving the efficiency of conventional solar cells toward the Shockley-Queisser limit seems to be slowing down or reaching a point of saturation. The challenges hindering the reduction of this efficiency gap can be categorized into extrinsic and intrinsic losses, with the former being theoretically avoidable. Among the five intrinsic losses, two — the below-Eg loss (resulting from non-absorption of photons with energy below the semiconductor bandgap) and thermalization loss —contribute to approximately 55% of the overall lost fraction of solar radiation at energy bandgap values corresponding to silicon and gallium arsenide. Efforts to minimize the disparity between theoretically predicted and experimentally achieved efficiencies in solar cells necessitate the integration of innovative physical concepts. Hot carriers (HC) present a contemporary approach to addressing this challenge. The significance of hot carriers in photovoltaics is not fully understood. Although their excessive energy is thought to indirectly impact a cell's performance through thermalization loss — where the excess energy heats the lattice, leading to efficiency loss — evidence suggests the presence of hot carriers in solar cells. Despite their exceptionally brief lifespan, tangible benefits arise from their existence. The study highlights direct experimental evidence of hot carrier effect induced by both below- and above-bandgap radiation in a singlejunction solar cell. Photocurrent flowing across silicon and GaAs p-n junctions is analyzed. The photoresponse consists, on the whole, of three components caused by electron-hole pair generation, hot carriers, and lattice heating. The last two components counteract the conventional electron-hole generation-caused current required for successful solar cell operation. Also, a model of the temperature coefficient of the voltage change of the current–voltage characteristic is used to obtain the hot carrier temperature. The distribution of cold and hot carriers is analyzed with regard to the potential barrier height of the p-n junction. These discoveries contribute to a better understanding of hot carrier phenomena in photovoltaic devices and are likely to prompt a reevaluation of intrinsic losses in solar cells.

Keywords: solar cell, hot carriers, intrinsic losses, efficiency, photocurrent

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Authors: Francisco Liaño-Carrera, José Isaac Ramírez-Macías, David Salas-Monreal, Mayra Lorena Riveron-Enzastiga, Marcos Rangel-Avalos, Adriana Andrea Roldán-Ubando

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The construction of most coastal infrastructure developments around the world are usually made considering wave height, current velocities and river discharges; however, little effort has been paid to surveying sediment transport during dredging or the modification to currents outside the ports or marinas during and after the construction. This study shows a complete survey during the construction of one of the largest ports of the Gulf of Mexico. An anchored Acoustic Doppler Current Velocity profiler (ADCP), a towed ADCP and a combination of model outputs were used at the Veracruz port construction in order to describe the hourly sediment transport and current modifications in and out of the new port. Owing to the stability of the system the new port was construction inside Vergara Bay, a low wave energy system with a tidal range of up to 0.40 m. The results show a two-current system pattern within the bay. The north side of the bay has an anticyclonic gyre, while the southern part of the bay shows a cyclonic gyre. Sediment transport trajectories were made every hour using the anchored ADCP, a numerical model and the weekly data obtained from the towed ADCP within the entire bay. The sediment transport trajectories were carefully tracked since the bay is surrounded by coral reef structures which are sensitive to sedimentation rate and water turbidity. The survey shows that during dredging and rock input used to build the wave breaker sediments were locally added (< 2500 m²) and local currents disperse it in less than 4 h. While the river input located in the middle of the bay and the sewer system plant may add more than 10 times this amount during a rainy day or during the tourist season. Finally, the coastal line obtained seasonally with a drone suggests that the southern part of the bay has not been modified by the construction of the new port located in the northern part of the bay, owing to the two subsystem division of the bay.

Keywords: Acoustic Doppler Current Profiler, construction around coral reefs, dredging, port construction, sediment transport monitoring,

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Authors: Eman Ismail, Adnan Masri

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Energy dissipation in ductile moment frames occurs mainly through plastic hinge rotations in its members (beams and columns). Generally, plastic hinge locations are pre-determined and limited to the beam ends, where columns are designed to remain elastic in order to avoid premature instability (aka story mechanisms) with the exception of column bases, where a base is 'fixed' in order to provide higher stiffness and stability and to form a plastic hinge. Plastic hinging at steel column bases in ductile moment frames using conventional base connection details is accompanied by several complications (thicker and heavily stiffened connections, larger embedment depths, thicker foundation to accommodate anchor rod embedment, etc.). An encased composite base connection is proposed where a segment of the column beginning at the base up to a certain point along its height is encased in reinforced concrete with headed shear studs welded to the column flanges used to connect the column to the concrete encasement. When the connection is flexurally loaded, stresses are transferred to a reinforced concrete encasement through the headed shear studs, and thereby transferred to the foundation by reinforced concrete mechanics, and axial column forces are transferred through the base-plate assembly. Horizontal base reactions are expected to be transferred by the direct bearing of the outer and inner faces of the flanges; however, investigation of this mechanism is not within the scope of this research. The inelastic and cyclic behavior of the connection will be investigated where it will be subjected to reversed cyclic loading, and rotational ductility will be observed in cases of yielding mechanisms where yielding occurs as flexural yielding in the beam-column, shear yielding in headed studs, and flexural yielding of the reinforced concrete encasement. The findings of this research show that the connection is capable of achieving satisfactory levels of ductility in certain conditions given proper detailing and proportioning of elements.

Keywords: seismic design, plastic mechanisms steel structure, moment frame, composite construction

Procedia PDF Downloads 107

Authors: Gabrielle Peck, Ryan Hayes

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Four façade systems were tested using a reduced height BS 8414-2 (5 m) test rig. An L-shaped masonry test wall was clad with three types of insulation and an aluminum composite panel with a non-combustible filling (meeting Euroclass A2). A large (3 MW) wooden crib was ignited in a recess at the base of the L, and the fire was allowed to burn for 30 minutes. Air velocity measurements and gas samples were taken from the main ventilation duct and also a small additional ventilation duct, like those in an apartment bathroom or kitchen. This provided a direct route of travel for smoke from the building façade to a theoretical room using a similar design to many high-rise buildings where the vent is connected to (approximately) 30 m³ rooms. The times to incapacitation and lethality of the effluent were calculated for both the main exhaust vent and for a vent connected to a theoretical 30 m³ room. The rainscreen façade systems tested were the common combinations seen in many tower blocks across the UK. Three tests using ACM A2 with Stonewool, Phenolic foam, and Polyisocyanurate (PIR) foam. A fourth test was conducted with PIR and ACM-PE (polyethylene core). Measurements in the main exhaust duct were representative of the effluent from the burning wood crib. FEDs showed incapacitation could occur up to 30 times quicker with combustible insulation than non-combustible insulation, with lethal gas concentrations accumulating up to 2.7 times faster than other combinations. The PE-cored ACM/PIR combination produced a ferocious fire, resulting in the termination of the test after 13.5 minutes for safety reasons. Occupants of the theoretical room in the PIR/ACM A2 test reached a FED of 1 after 22 minutes; for PF/ACM A2, this took 25 minutes, and for stone wool, a lethal dose measurement of 0.6 was reached at the end of the 30-minute test. In conclusion, when measuring smoke toxicity in the exhaust duct, there is little difference between smoke toxicity measurements between façade systems. Toxicity measured in the main exhaust is largely a result of the wood crib used to ignite the façade system. The addition of a vent allowed smoke toxicity to be quantified in the cavity of the façade, providing a realistic way of measuring the toxicity of smoke that could enter an apartment from a façade fire.

Keywords: smoke toxicity, large-scale testing, BS8414, FED

Procedia PDF Downloads 38

Authors: Mustafa M. Donma, Orkide Donma

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Anthropometric obesity indices such as waist circumference (WC), indices derived from anthropometric measurements such as waist-to-hip ratio (WHR), and indices created from body fat mass composition such as trunk-to-leg fat ratio (TLFR) are commonly used for the evaluation of mild or severe forms of obesity. Their clinical utilities are being compared using body mass index (BMI) percentiles to classify obesity groups. The best of them is still being investigated to make a clear-cut discrimination between healthy normal individuals (N-BMI) and overweight or obese (OB) or morbid obese patients. The aim of this study is to derive a new index, which best suits the purpose for the discrimination of children with N-BMI from OB children. A total of eighty-three children participated in the study. Two groups were constituted. The first group comprised 42 children with N-BMI, and the second group was composed of 41 OB children, whose age- and sex- adjusted BMI percentile values vary between 95 and 99. The corresponding values for the first group were between 15 and 85. This classification was based upon the tables created by World Health Organization. The institutional ethics committee approved the study protocol. Informed consent forms were filled by the parents of the participants. Anthropometric measurements were taken and recorded following a detailed physical examination. Within this context, weight, height (Ht), WC, hip C (HC), neck C (NC) values were taken. Body mass index, WHR, (WC+HC)/2, WC/Ht, (WC/HC)/Ht, WC*NC were calculated. Bioelectrical impedance analysis was performed to obtain body’s fat compartments in terms of total fat, trunk fat, leg fat, arm fat masses. Trunk-to-leg fat ratio, trunk-to-appendicular fat ratio (TAFR), (trunk fat+leg fat)/2 ((TF+LF)/2) were calculated. Fat mass index (FMI) and diagnostic obesity notation model assessment-II (D2I) index values were calculated. Statistical analysis of the data was performed. Significantly increased values of (WC+HC)/2, (TF+LF)/2, D2I, and FMI were observed in OB group in comparison with those of N-BMI group. Significant correlations were calculated between BMI and WC, (WC+HC)/2, (TF+LF)/2, TLFR, TAFR, D2I as well as FMI both in N-BMI and OB groups. The same correlations were obtained for WC. (WC+HC)/2 was correlated with TLFR, TAFR, (TF+LF)/2, D2I, and FMI in N-BMI group. In OB group, the correlations were the same except those with TLFR and TAFR. These correlations were not present with WHR. Correlations were observed between TLFR and BMI, WC, (WC+HC)/2, (TF+LF)/2, D2I as well as FMI in N-BMI group. Same correlations were observed also with TAFR. In OB group, correlations between TLFR or TAFR and BMI, WC as well as (WC+HC)/2 were missing. None was noted with WHR. From these findings, it was concluded that (WC+HC)/2, but not WHR, was much more suitable as an anthropometric obesity index. The only correlation valid in both groups was that exists between (WC+HC)/2 and (TF+LF)/2. This index was suggested as a link between anthropometric and fat-based indices.

Keywords: children, hip circumference, obesity, waist circumference

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Authors: Ákos Tótin

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In crop production the most modern hybrids are available for us, therefore the yield and yield stability is determined by the agro-technology. The purpose of the experiment is to adapt the modern agrotechnology to the new type of hybrids. The long-term experiment was set up in 2015-2016 on chernozem soil in the Hajdúság (eastern Hungary). The plots were set up in 75 thousand ha-1 plant density. We examined some mainly use hybrids of Hungary. The conducted studies are: germination dynamic, growing dynamic and the effect of annual weather for the yield. We use three different sowing date as early, average and late, and measure how many plant germinated during the germination process. In the experiment, we observed the germination dynamics in 6 hybrid in 4 replication. In each replication, we counted the germinated plants in 2m long 2 row wide area. Data will be shown in the average of the 6 hybrid and 4 replication. Growing dynamics were measured from the 10cm (4-6 leaf) plant highness. We measured 10 plants’ height in two weeks replication. The yield was measured buy a special plot harvester - the Sampo Rosenlew 2010 – what measured the weight of the harvested plot and also took a sample from it. We determined the water content of the samples for the water release dynamics. After it, we calculated the yield (t/ha) of each plot at 14% of moisture content to compare them. We evaluated the data using Microsoft Excel 2015. The annual weather in each crop year define the maize germination dynamics because the amount of heat is determinative for the plants. In cooler crop year the weather is prolonged the germination. At the 2015 crop year the weather was cold in the beginning what prolonged the first sowing germination. But the second and third sowing germinated faster. In the 2016 crop year the weather was much favorable for plants so the first sowing germinated faster than in the previous year. After it the weather cooled down, therefore the second and third sowing germinated slower than the last year. The statistical data analysis program determined that there is a significant difference between the early and late sowing date growing dynamics. In 2015 the first sowing date had the highest amount of yield. The second biggest yield was in the average sowing time. The late sowing date has lowest amount of yield.

Keywords: germination, maize, sowing date, yield

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Authors: Ashu Rastogi, Uttam Thakur, Jimmy Pathak, Rajesh Gupta, Anil Bhansali

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Introduction: Liraglutide is known to induce weight loss and metabolic benefits in obese individuals. However, its effect after sleeve gastrectomy are not known. Methods: People with obesity (BMI>27.5 kg/m2) underwent LSG. Subsequently, participants were randomized to receive either 0.6mg liraglutide subcutaneously daily from 6 week post to be continued till 24 week (L-L group) or placebo (L-P group). Patients were assessed before surgery (baseline) and 6 weeks, 12weeks, 18weeks and 24weeks after surgery for height, weight, waist and hip circumference, BMI, body fat percentage, HbA1c, fasting C-peptide, fasting insulin, HOMA-IR, HOMA-β, GLP-1 levels (after standard OGTT). MRI abdomen was performed prior to surgery and at 24weeks post operatively for the estimation of intrapancreatic and intrahepatic fat content. Outcome measures: Primary outcomes were changes in metabolic variables of fasting and stimulated GLP-1 levels, insulin, c-peptide, plasma glucose levels. Secondary variables were indices of insulin resistance HOMA-IR, Matsuda index; and pancreatic and hepatic steatosis. Results: Thirty-eight patients undergoing LSG were screened and 29 participants were enrolled. Two patients withdrew consent and one patient died of acute coronary event. 26 patients were randomized and data analysed. Median BMI was 40.73±3.66 and 46.25±6.51; EBW of 49.225±11.14 and 651.48±4.85 in the L-P and L-L group, respectively. Baseline FPG was 132±51.48, 125±39.68; fasting insulin 21.5±13.99, 13.15±9.20, fasting GLP-1 2.4± .37, 2.4± .32, AUC GLP-1 340.78± 44 and 332.32 ± 44.1, HOMA-IR 7.0±4.2 and 4.42±4.5 in the L-P and L-L group, respectively. EBW loss was 47± 13.20 and 65.59± 24.20 (p<0.05) in the placebo versus liraglutide group. However, we did not observe inter-group difference in metabolic parameters between the groups in spite of significant intra-group changes after 6 months of LSG. Intra-pancreatic fat prior to surgery was 3.21±1.7 and 2.2±0.9 (p=0.38) that decreased to 2.14±1.8 and 1.06±0.8 (p=0.25) at 6 months in L-P and L-L group, respectively. Similarly, intra-pancreatic fat was 1.97±0.27 and 1.88±0.36 (p=0.361) at baseline that decreased to 1.14±0.44 and 1.36±0.47 (p=0.465) at 6 months in L-P and L-L group, respectively. Conclusion: Liraglutide augments extra body weight loss after sleeve gastrectomy. A decrease in intra-pancreatic and intra-hepatic fat is noticed after bariatric surgery without additive benefit of liraglutide administration.

Keywords: sleeve gastrectomy, liraglutide, intra-pancreatic fat, insulin

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Authors: Olawale S. Fatoba, Stephen A. Akinlabi, Esther T. Akinlabi, Rezvan Gharehbaghi

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The performance of material surface under wear and corrosion environments cannot be fulfilled by the conventional surface modifications and coatings. Therefore, different industrial sectors need an alternative technique for enhanced surface properties. Titanium and its alloys possess poor tribological properties which limit their use in certain industries. This paper focuses on the effect of hybrid coatings Al-Cu-Fe on a grade five titanium alloy using laser metal deposition (LMD) process. Icosahedral Al-Cu-Fe as quasicrystals is a relatively new class of materials which exhibit unusual atomic structure and useful physical and chemical properties. A 3kW continuous wave ytterbium laser system (YLS) attached to a KUKA robot which controls the movement of the cladding process was utilized for the fabrication of the coatings. The titanium cladded surfaces were investigated for its hardness, corrosion and tribological behaviour at different laser processing conditions. The samples were cut to corrosion coupons, and immersed into 3.65% NaCl solution at 28oC using Electrochemical Impedance Spectroscopy (EIS) and Linear Polarization (LP) techniques. The cross-sectional view of the samples was analysed. It was found that the geometrical properties of the deposits such as width, height and the Heat Affected Zone (HAZ) of each sample remarkably increased with increasing laser power due to the laser-material interaction. It was observed that there are higher number of aluminum and titanium presented in the formation of the composite. The indentation testing reveals that for both scanning speed of 0.8 m/min and 1m/min, the mean hardness value decreases with increasing laser power. The low coefficient of friction, excellent wear resistance and high microhardness were attributed to the formation of hard intermetallic compounds (TiCu, Ti2Cu, Ti3Al, Al3Ti) produced through the in situ metallurgical reactions during the LMD process. The load-bearing capability of the substrate was improved due to the excellent wear resistance of the coatings. The cladded layer showed a uniform crack free surface due to optimized laser process parameters which led to the refinement of the coatings.

Keywords: Al-Cu-Fe coating, corrosion, intermetallics, laser metal deposition, Ti-6Al-4V alloy, wear resistance

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Authors: Bencharif Meriem, Sersar Ibrahim, Djaafri Zineb

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Introduction and purpose of the study: Education plays a fundamental role in the lives of young people, but what about their physical well-being as they spend long hours sitting at school? School inactivity is a problem that deserves particular attention because it can have significant repercussions on the health and development of students. The aim of this study was to describe and evaluate the physical activity of students in different practices in class, at recess and in the canteen. Material and methods: A physical activity diary and an anthropometric measurement sheet (weight, height) were provided to 123 school-aged adolescents. The measurements were carried out according to international recommendations. The statistical tests were carried out with the R software. 3.2.4. The significance threshold retained was 0.05. Results and Statistical Analysis: One hundred and twenty-three students agreed to participate in the study. Their average age was 16.5±1.60 years. Overweight was present in 8.13% and obesity in 4.06%. For the practice of physical activity, during physical education and sports classes, all students played sports with an average of 1.94±1.00 hours/week, of which 74.00% sweated or were out of breath during these hours of physical activity. It was also noted that boys practiced sports more than girls (p<0.0001). Each day, on average, students spent 39.78±37.85 min walking or running during recess. On the other hand, they spent, on average 4.25±2.65 hours sitting per day in class, at recess, in the canteen, etc., without counting the time spent in front of a screen. The increasing use of screens has become a major concern for parents and educators. On average, students spent approximately 42.90±38.41 min per day using screens in class, at recess, in the canteen and at home. (computer, tablet, telephone, video games, etc.) and therefore to a prolonged sedentary lifestyle. On average, students sat for more than 1.5 hours without moving for at least 2 minutes in a row approximately 1.72±0.71 times per day. Conclusion: These students spent many hours sitting at school. This prolonged inactivity can have negative consequences on their health, including problems with posture and cardiovascular health. It is crucial that schools, educators and parents collaborate to promote more active learning environments where students can move more and thus contribute to their overall well-being. It's time to rethink how we approach education and student health to give them a healthier, more active future.

Keywords: physical acivity, sedentarity, adolescents, school

Procedia PDF Downloads 40

Authors: E. Ormeno, C. Gutigny, J. Ruffault, J. Madrigal, M. Guijarro, C. Lecareux, C. Ballini

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Mediterranean plant species feature numerous metabolic and morpho-physiological responses crucial to survive under both, typical Mediterranean drought conditions and future aggravated drought expected by climate change. Whether these adaptive responses will, in turn, increase the ecosystem perturbation in terms of fire hazard, is an issue that needs to be addressed. The aim of this study was to test whether recurrent and aggravated drought in the Mediterranean area favors the accumulation of waxes in leaf litter, with an eventual increase of litter flammability. The study was conducted in 2017 in a garrigue in Southern France dominated by Quercus coccifera, where two drought treatments were used: a treatment with recurrent aggravated drought consisting of ten rain exclusion structures which withdraw part of the annual precipitation since January 2012, and a natural drought treatment where Q. coccifera stands are free of such structures and thus grow under natural precipitation. Waxes were extracted with organic solvent and analyzed by GC-MS and litter flammability was assessed through measurements of the ignition delay, flame residence time and flame intensity (flame height) using an epiradiator as well as the heat of combustion using an oxygen bomb calorimeter. Results show that after 5 years of rain restriction, wax content in the cuticle of leaf litter increases significantly compared to shrubs growing under natural precipitation, in accordance with the theoretical knowledge which expects increases of cuticle waxes in green leaves in order to limit water evapotranspiration. Wax concentrations were also linearly and positively correlated to litter flammability, a correlation that lies on the high flammability own to the long-chain alkanes (C25-C31) found in leaf litter waxes. This innovative investigation shows that climate change is likely to favor ecosystem fire hazard through accumulation of highly flammable waxes in litter. It also adds valuable information about the types of metabolites that are associated with increasing litter flammability, since so far, within the leaf metabolic profile, only terpene-like compounds had been related to plant flammability.

Keywords: cuticular waxes, drought, flammability, litter

Procedia PDF Downloads 147

Authors: Linjie Zhang, Baifen Ren, Xi Zhang, Genwang Liu

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Ship detection is of great significance for both military and civilian applications. Synthetic aperture radar (SAR) with all-day, all-weather, ultra-long-range characteristics, has been used widely. In view of the low time resolution of low orbit SAR and the needs for high time resolution SAR data, GEO (Geosynchronous orbit) SAR is getting more and more attention. Since GEO SAR has short revisiting period and large coverage area, it is expected to be well utilized in marine ship targets monitoring. However, the height of the orbit increases the time of integration by almost two orders of magnitude. For moving marine vessels, the utility and efficacy of GEO SAR are still not sure. This paper attempts to find the feasibility of GEO SAR by giving a GEO SAR simulator of moving ships. This presented GEO SAR simulator is a kind of geometrical-based radar imaging simulator, which focus on geometrical quality rather than high radiometric. Inputs of this simulator are 3D ship model (.obj format, produced by most 3D design software, such as 3D Max), ship's velocity, and the parameters of satellite orbit and SAR platform. Its outputs are simulated GEO SAR raw signal data and SAR image. This simulating process is accomplished by the following four steps. (1) Reading 3D model, including the ship rotations (pitch, yaw, and roll) and velocity (speed and direction) parameters, extract information of those little primitives (triangles) which is visible from the SAR platform. (2) Computing the radar scattering from the ship with physical optics (PO) method. In this step, the vessel is sliced into many little rectangles primitives along the azimuth. The radiometric calculation of each primitive is carried out separately. Since this simulator only focuses on the complex structure of ships, only single-bounce reflection and double-bounce reflection are considered. (3) Generating the raw data with GEO SAR signal modeling. Since the normal ‘stop and go’ model is not available for GEO SAR, the range model should be reconsidered. (4) At last, generating GEO SAR image with improved Range Doppler method. Numerical simulation of fishing boat and cargo ship will be given. GEO SAR images of different posture, velocity, satellite orbit, and SAR platform will be simulated. By analyzing these simulated results, the effectiveness of GEO SAR for the detection of marine moving vessels is evaluated.

Keywords: GEO SAR, radar, simulation, ship

Procedia PDF Downloads 145

Authors: Fakunle Egbo, Kammalchukwu A., Akinremi T.

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Physical activity and nutritional status influence the health status and cognition of young adults. Lack of physical activity increases the likelihood of developing obesity which leads to the risk of heart diseases and other risk factors like high blood pressure, high blood cholesterol, diabetes etc. The study employed a cross-sectional study design. The study used a multi stage sampling technique multi- stage sampling technique; Purposive, for the selection of colleges that would be used, stratified random sampling for stratifying the colleges into departments and the simple random sampling for the selection of each respondent from the departments. Structured questionnaires were used to obtain data from the respondents and pre-tested anthropometric instruments were used to get the weight and height of the respondents and statistically analyzed using SPSS version 22.0 and the TDA (Total dietary allowance) software which was used to analyze the nutrient intake of the respondents. This study showed that they comprised of 50.1% males and 40.9% females. Slightly above average 51.8% were between ages of 15-19 with mean age being 19.57 years; ages 20-24 were slightly below average at 45.7%. The male students 58.7% had vigorous physical activity, whereas majority of females 76.5% had light physical activity level. 39.1% of the male students carried out physical activity 2-3 times per week while One third of the female students (38.3%) carried out physical activity 6-7 times per week. Majority of the respondents had Inadequate Protein- 63.8%, Carbohydrate- 60.2%, and Dietary fiber- 88.8. 36% eat rice 4-6 times per week. Majority of the respondents had inadequate fruit and vegetables (Efo, Banana,) at 47.7%, 40.6% respectively. Using Body mass index, (63.2%) have normal weight. 22.9% are overweight, 6.8% are underweight, 5.4% have grade 1 obesity and 1.6% have grade II obesity. There was a statistically significant association between the physical activity of the respondents with their nutritional status (p=0.037), physical activity and sex (p=0.000), nutritional status and amount spent on food daily (p=0.007). The study concluded that the physical activity level of the respondents, most especially the females were low; One third of the students were malnourished therefore, there should be an urgent need for improving the overall health status of students by providing the students with well-equipped gyms and other sporting equipment’s that would make them participate actively and keep fit.

Keywords: physical activity, nutritional status, undergraduates, dietary pattern

Procedia PDF Downloads 45

Authors: Saeed Qaisrani

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The study was conducted to observe carbon and nutrient loss by burning of rice residues on rice-wheat cropping system The rice crop was harvested to conduct the experiment in a randomized complete block design (RCBD) with factors and 4 replications with a net plot size of 10 m x 20 m. Rice stubbles were managed by two methods i.e. Incorporation & burning of rice residues. Soil samples were taken to a depth of 30 cm before sowing & after harvesting of wheat. Wheat was sown after harvesting of rice by three practices i.e. Conventional tillage, Minimum tillage and Zero tillage to observe best tillage practices. Laboratory and field experiments were conducted on wheat to assess best tillage practice and residues management method with estimation of carbon losses. Data on the following parameters; establishment count, plant height, spike length, number of grains per spike, biological yield, fat content, carbohydrate content, protein content, and harvest index were recorded to check wheat quality & ensuring food security in the region. Soil physico-chemical analysis i.e. pH, electrical conductivity, organic matter, nitrogen, phosphorus, potassium, and carbon were done in soil fertility laboratory. Substantial results were found on growth, yield and related parameters of wheat crop. The collected data were examined statistically with economic analysis to estimate the cost-benefit ratio of using different tillage techniques and residue management practices. Obtained results depicted that Zero tillage method have positive impacts on growth, yield and quality of wheat, Moreover, it is cost effective methodology. Similarly, Incorporation is suitable and beneficial method for soil due to more nutrients provision and reduce the need of fertilizers. Burning of rice stubbles has negative impact including air pollution, nutrient loss, microbes died and carbon loss. Recommended the zero tillage technology to reduce carbon losses along with food security in Pakistan.

Keywords: agricultural agronomy, food security, carbon sequestration, rice-wheat cropping system

Procedia PDF Downloads 255

Authors: Bruna P. De Souza, Ricardo C. De Almeida

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In some cities in the State of Parana – Brazil and in other countries atmospheric bromeliads (Tillandsia spp - Bromeliaceae) are considered weeds in trees, electric power lines, satellite dishes and other artificial supports. In this study, a numerical model was developed to simulate the seed dispersal of the Tillandsia recurvata species by wind with the objective of evaluating seeds displacement in the city of Ponta Grossa – PR, Brazil, since it is considered that the region is already infested. The model simulates the dispersal of each individual seed integrating parameters from the atmospheric boundary layer (ABL) and the local wind, simulated by the Weather Research Forecasting (WRF) mesoscale atmospheric model for the 2012 to 2015 period. The dispersal model also incorporates the approximate number of bromeliads and source height data collected from most infested electric power lines. The seeds terminal velocity, which is an important input data but was not available in the literature, was measured by an experiment with fifty-one seeds of Tillandsia recurvata. Wind is the main dispersal agent acting on plumed seeds whereas atmospheric turbulence is a determinant factor to transport the seeds to distances beyond 200 meters as well as to introduce random variability in the seed dispersal process. Such variability was added to the model through the application of an Inverse Fast Fourier Transform to wind velocity components energy spectra based on boundary-layer meteorology theory and estimated from micrometeorological parameters produced by the WRF model. Seasonal and annual wind means were obtained from the surface wind data simulated by WRF for Ponta Grossa. The mean wind direction is assumed to be the most probable direction of bromeliad seed trajectory. Moreover, the atmospheric turbulence effect and dispersal distances were analyzed in order to identify likely regions of infestation around Ponta Grossa urban area. It is important to mention that this model could be applied to any species and local as long as seed’s biological data and meteorological data for the region of interest are available.

Keywords: atmospheric turbulence, bromeliad, numerical model, seed dispersal, terminal velocity, wind

Procedia PDF Downloads 118

Authors: Muhammad Aown Sammar Raza

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Environmental stresses are one of the major reasons for poor crop yield across the globe. Among the various environmental stresses, drought stress is the most damaging one, especially in arid and semi-arid regions. Wheat is the major staple food of many countries of the world, which is badly affected by drought stress. In order to fulfill the dietary needs of increasing population with depleting water resources there is a need to adopt technologies which result in sufficient crop yield with less water consumption. One of them is partial root zone drying. Keeping in view these conditions, a wire house experiment was conducted at agronomic research area of University College of Agriculture and Environmental Sciences, The Islamia University Bahawalpur during 2015, to screen out the different wheat varieties for partial root zone drying (PRD). Five approved local wheat varieties (V1= Galaxy-2013, V2= Punjab-2011, V3 = Faisalabad-2008, V4 = Lasani-2008 and V5 = V.8200) and two irrigation levels (I1= control irrigation and I2 = PRD irrigation) with completely randomized design having four replications were used in the experiment. Among the varieties, Galaxy-2013 performed the best and attained maximum plant height, leaf area, stomatal conductance, photosynthesis, total sugars, proline contents and antioxidant enzymes activities and minimum values of growth and physiological parameters were recorded in variety V.8200. For irrigation levels, higher values of growth, physiological and water related parameters were recorded in control treatment (I1) except leaf water potential, osmotic potential, total sugars and proline contents. However, enzyme activities were higher under PRD treatment for all varieties. It was concluded that Galaxy-2013 is the most compatible and V.8200 is the most susceptible variety for PRD, respectively and more quality traits and enzymatic activities were recorded under PRD irrigation as compared to control treatment.

Keywords: antioxidant enzymes activities, osmolytes concentration, partial root zone drying, photosynthetic rate, water relations, wheat

Procedia PDF Downloads 215

Authors: Shani Brathwaite, Deborah Villarroel-Lamb

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Wave run-up may be defined as the time-varying position of the landward extent of the water’s edge, measured vertically from the mean water level position. The hydrodynamics of the swash zone and the accurate prediction of maximum wave run-up, play a critical role in the study of coastal engineering. The understanding of these processes is necessary for the modeling of sediment transport, beach recovery and the design and maintenance of coastal engineering structures. However, due to the complex nature of the swash zone, there remains a lack of detailed knowledge in this area. Particularly, there has been found to be insufficient consideration of bed porosity and ultimately infiltration/exfiltration processes, in the development of wave run-up models. Theoretically, there should be an inverse relationship between maximum wave run-up and beach porosity. The greater the rate of infiltration during an event, associated with a larger bed porosity, the lower the magnitude of the maximum wave run-up. Additionally, most models have been developed using data collected on North American or Australian beaches and may have limitations when used for operational forecasting in Trinidad. This paper aims to assess the influence and significance of infiltration and exfiltration processes on wave run-up magnitudes within the swash zone. It also seeks to pay particular attention to how well various empirical formulae can predict maximum run-up on contrasting beaches in Trinidad. Traditional surveying techniques will be used to collect wave run-up and cross-sectional data on various beaches. Wave data from wave gauges and wave models will be used as well as porosity measurements collected using a double ring infiltrometer. The relationship between maximum wave run-up and differing physical parameters will be investigated using correlation analyses. These physical parameters comprise wave and beach characteristics such as wave height, wave direction, period, beach slope, the magnitude of wave setup, and beach porosity. Most parameterizations to determine the maximum wave run-up are described using differing parameters and do not always have a good predictive capability. This study seeks to improve the formulation of wave run-up by using the aforementioned parameters to generate a formulation with a special focus on the influence of infiltration/exfiltration processes. This will further contribute to the improvement of the prediction of sediment transport, beach recovery and design of coastal engineering structures in Trinidad.

Keywords: beach porosity, empirical models, infiltration, swash, wave run-up

Procedia PDF Downloads 323

Authors: A.Assariotakis, P. Vahamidis, P. Tarantilis, G. Economou

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Greece, due to its geographical location and the particular climatic conditions, presents high biodiversity of Medicinal and Aromatic Plants. Among them, the genus Origanum not only presents a wide distribution, but it also has great economic importance. After extensive surveys in Ikaria Island (Greece), 3 species of the genus Origanum were identified, namely, Origanum vulgare ssp. hirtum (Greek oregano), Origanum onites (Turkish oregano) and Origanum x intercedens (hybrid), a naturally occurring hybrid between O. hirtum and O. onites. The purpose of this study was to determine their morphological as well as their temporal variability in essential oil yield and composition under field conditions. For this reason, a plantation of each species was created using vegetative propagation and was established at the experimental field of the Agricultural University of Athens (A.U.A.). From the establishment year and for the following two years (3 years of observations), several observations were taken during each growing season with the purpose of identifying the morphological differences among the studied species. Each year collected plant (at bloom stage) material was air-dried at room temperature in the shade. The essential oil content was determined by hydrodistillation using a Clevenger-type apparatus. The chemical composition of essential oils was investigated by Gas Chromatography-Mass Spectrometry (GC – MS). Significant differences were observed among the three oregano species in terms of plant height, leaf size, inflorescence features, as well as concerning their biological cycle. O. intercedens inflorescence presented more similarities with O. hirtum than with O. onites. It was found that calyx morphology could serve as a clear distinction feature between O. intercedens and O. hirtum. The calyx in O. hirtum presents five isometric teeth whereas in O. intercedens two high and three shorter. Essential oil content was significantly affected by genotype and year. O. hirtum presented higher essential oil content than the other two species during the first year of cultivation, however during the second year the hybrid (O. intercedens) recorded the highest values. Carvacrol, p-cymene and γ-terpinene were the main essential oil constituents of the three studied species. In O. hirtum carvacrol content varied from 84,28 - 93,35%, in O. onites from 86,97 - 91,89%, whereas in O. intercedens it was recorded the highest carvacrol content, namely from 89,25 - 97,23%.

Keywords: variability, oregano biotypes, essential oil, carvacrol

Procedia PDF Downloads 109

Authors: Sireetorn Kuharat, Anwar Beg

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In this study, multi-mode heat transfer characteristics of spacecraft solar collectors are investigated computationally. Two-dimensional steady-state incompressible laminar Newtonian viscous convection-radiative heat transfer in a rectangular solar collector geometry. The ANSYS FLUENT finite volume code (version 17.2) is employed to simulate the thermo-fluid characteristics. Several radiative transfer models are employed which are available in the ANSYS workbench, including the classical Rosseland flux model and the more elegant P1 flux model. Mesh-independence tests are conducted. Validation of the simulations is conducted with a computational Harlow-Welch MAC (Marker and Cell) finite difference method and excellent correlation. The influence of aspect ratio, Prandtl number (Pr), Rayleigh number (Ra) and radiative flux model on temperature, isotherms, velocity, the pressure is evaluated and visualized in color plots. Additionally, the local convective heat flux is computed and solutions are compared with the MAC solver for various buoyancy effects (e.g. Ra = 10,000,000) achieving excellent agreement. The P1 model is shown to better predict the actual influence of solar radiative flux on thermal fluid behavior compared with the limited Rosseland model. With increasing Rayleigh numbers the hot zone emanating from the base of the collector is found to penetrate deeper into the collector and rises symmetrically dividing into two vortex regions with very high buoyancy effect (Ra >100,000). With increasing Prandtl number (three gas cases are examined respectively hydrogen gas mixture, air and ammonia gas) there is also a progressive incursion of the hot zone at the solar collector base higher into the solar collector space and simultaneously a greater asymmetric behavior of the dual isothermal zones. With increasing aspect ratio (wider base relative to the height of the solar collector geometry) there is a greater thermal convection pattern around the whole geometry, higher temperatures and the elimination of the cold upper zone associated with lower aspect ratio.

Keywords: thermal convection, radiative heat transfer, solar collector, Rayleigh number

Procedia PDF Downloads 99

Authors: Fahad Al Yahyaey, Ihab Shaat, Russell Bush

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This study was conducted at the Livestock Research Centre, Ministry of Agriculture and Fisheries, Oman, on two local goat breeds (Jabbali and Sahrawi) due to their importance to Omani livestock production and food security. The Jabbali is characterized by increased growth rates and a higher twinning rate, while the Sahrawi has increased milk production. The aim of the study was to investigate the effect of Spirulina supplementation on live weight (BWT), average daily gain (ADG), and body conformation measurements; chest girth (CG), wither height (WH), body length (BL), and body condition score (BCS). Thirty-six males (approximately nine-months-old and 16.44 ± 0.33 kg average of initial body weight) were used across an eleven-week study from November–February 2019-2020. Each breed was divided into three groups (n = 6/group) and fed one of three rations: (1) concentrate mixture (Control) with crude protein 14% and energy 11.97% MJ/kg DM; (2) the same concentrate feed with the addition of 2 gm /capita daily Spirulina platensis (Treatment 1) and (3) the same concentrate feed with the addition of 4 gm /capita daily Spirulina platensis (Treatment 2). Analysis of weekly data collections for all traits indicated a significant effect of feeding Spirulina on all the studied traits except WH and BL. Analysis of variance for fixed effects in this study (damage and kid birth type i.e., single, twin or triple) were not significant for all studied traits. However, the breed effect was highly significant (P < 0.001) on BWT, ADG, BCS, and CG traits. On the other hand, when the analysis was done for the treatment effect within breeds for ADG, the Sahrawi breed had a significant effect (P < 0.05) at 56.52, 85.51, and 85.50 g/day for control, treatment 1 and treatment 2, respectively. This is a 51% difference between the control and treatment 1 (2 gm /capita). Whereas for the Jabbali breed, the treatment effect was not significant for ADG (P =0.55), and the actual ADG was 104.59, 118.84, and 114.25 g/day for control, treatment 1, and treatment 2, respectively, providing a 14% difference between the control group and the treated group (4 gm /capita). These findings indicate using Spirulina supplementation in Omani goat diets is recommended at 2 gm per capita as there was no benefit in feeding at 4 gm per capita for either breed. Farmers feeding Spirulina supplementation to kids after weaning at six-months could increase their herd performance and growth rate and facilitate buck selection at an earlier age.

Keywords: body conformation, goats, live weight, spirulina

Procedia PDF Downloads 81

Authors: K. Alafogiannis, E. E. Houssos, E. Anagnostou, G. Kouvarakis, N. Mihalopoulos, A. Fotiadi

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The Mediterranean basin is an area where different aerosol types coexist, including urban/industrial, desert dust, biomass burning and marine particles. Particularly, mineral dust aerosols, mostly originated from North African deserts, significantly contribute to high aerosol loads above the Mediterranean. Dust transport, controlled by the variation of the atmospheric circulation throughout the year, results in a strong spatial and temporal variability of aerosol properties. In this study, the synoptic conditions which favor dust transport over the Eastern Mediterranean are thoroughly investigated. For this reason, three datasets are employed. Firstly, ground-based daily data of aerosol properties, namely Aerosol Optical Thickness (AOT), Ångström exponent (α440-870) and fine fraction from the FORTH-AERONET (Aerosol Robotic Network) station along with measurements of PM10 concentrations from Finokalia station, for the period 2003-2011, are used to identify days with high coarse aerosol load (episodes) over Crete. Then, geopotential height at 1000, 850 and 700 hPa levels obtained from the NCEP/NCAR Reanalysis Project, are utilized to depict the atmospheric circulation during the identified episodes. Additionally, air-mass back trajectories, calculated by HYSPLIT, are used to verify the origin of aerosols from neighbouring deserts. For the 227 identified dust episodes, the statistical methods of Factor and Cluster Analysis are applied on the corresponding atmospheric circulation data to reveal the main types of the synoptic conditions favouring dust transport towards Crete (Eastern Mediterranean). The 227 cases are classified into 11 distinct types (clusters). Dust episodes in Eastern Mediterranean, are found to be more frequent (52%) in spring with a secondary maximum in autumn. The main characteristic of the atmospheric circulation associated with dust episodes, is the presence of a low-pressure system at surface, either in southwestern Europe or western/central Mediterranean, which induces a southerly air flow favouring dust transport from African deserts. The exact position and the intensity of the low-pressure system vary notably among clusters. More rarely dust may originate from deserts of Arabian Peninsula.

Keywords: aerosols, atmospheric circulation, dust particles, Eastern Mediterranean

Procedia PDF Downloads 208

Authors: Zhongzhong Zeng, Zichen Liang

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In recent years, Beijing courtyards have been facing the problem of renewal and renovation, and the residents are faced with the problems of small house areas, large household sizes, old and dangerous houses, etc. Among the many renovation methods, the authors note two more common practices of using the front porch to expand the floor area and adding a loft. Residents and architects, however, did not give the ventilation performance of the significant interior consideration before beginning the remodeling. The aim of this article is to explore the good or negative impacts of both front porch and loft structures on the manner of interior ventilation in the courtyard. Ventilation, in turn, is crucial to the indoor environmental quality of a home. The major method utilized in this study is the comparative analysis method, in which the authors create four alternative house models with or without a front porch and an attic as two variables and examine internal ventilation using the CFD(Computational Fluid Dynamics) technique. The authors compare the indoor ventilation of four different architectural models with or without front porches and lofts as two variables. The results obtained from the analysis of the sectional airflow and the plane 1.5m height cloud are the existence of the loft, to a certain extent, disrupts the airflow organization of the building and makes the rear wall high windows of the building less effective. Occupying the front porch to become the area of the house has no significant effect on ventilation, but try not to occupy the front porch and add the loft at the same time in the building renovation. The findings of this study led to the following recommendations: strive to preserve the courtyard building's original architectural design and make adjustments to only the inappropriate elements or constructions. The ventilation in the loft portion is inadequate, and the inhabitants typically use the loft as a living area. This may lead to the building relying more on air conditioning in the summer, which would raise energy demand. The front porch serves as a transition place as well as a source of shade, weather protection, and inside ventilation. In conclusion, the examination of interior environments in upcoming studies should concentrate on cross-disciplinary, multi-angle, and multi-level research topics.

Keywords: Beijing courtyard renewal, CFD, indoor environment, ventilation analysis

Procedia PDF Downloads 58

Authors: Giovana Longo-Silva, Risia Cristina Egito de Menezes, Renan Serenini, Márcia de Oliveira Lima, Júlia Souza de Melo, Larissa de Lima Soares

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Introduction: Sleep duration and quality have been increasingly recognized as important factors affecting overall health and well-being, including their potential impact on body weight and composition. Previous research has shown inconsistent results regarding the association between sleep patterns and body mass index (BMI), particularly among diverse populations such as Brazilian adults. Understanding these relationships is crucial for developing targeted interventions to address obesity and related health issues. Objective: This study aimed to investigate the association between sleep duration, insomnia, and BMI among Brazilian adults using data from a large national survey focused on chronic nutrition and sleep habits. Materials and Methods: The study included 2050 participants from a population-based virtual survey. BMI was calculated using self-reported weight and height measurements. Participants also reported usual bedtime and wake time on weekdays and weekends and whether they experienced symptoms of insomnia. The average sleep duration across the entire week was calculated as follows: [(5×sleep duration on weekdays) + (2×sleep duration on weekends)]/7. Linear regression analyses were conducted to assess the association between sleep duration, insomnia, and BMI, adjusting for potential confounding factors, including age, sex, marital status, physical exercise duration, and diet quality. Results: After adjusting for confounding variables, the study found that BMI decreased by 0.19 kg/m² for each additional hour of sleep duration (95% CI = -0.37, -0.02; P = 0.03). Conversely, individuals with insomnia had a higher BMI, with an increase of 0.75 kg/m² (95% CI = 0.28, 1.22; P = 0.002) compared to those without insomnia. Conclusions: The findings suggest a significant association between sleep duration, insomnia, and BMI among Brazilian adults. Longer sleep duration was associated with lower BMI, while insomnia was associated with higher BMI. These results underscore the importance of considering sleep patterns in strategies aimed at preventing and managing obesity in this population. Further research is needed to explore the underlying mechanisms and potential interventions targeting sleep-related factors to promote healthier body weight outcomes.

Keywords: sleep, obesity, chronobiology, nutrition

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Authors: Liliana Rusu

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The goal of the proposed work is to provide a more comprehensive picture of the wind and wave climate in the Romanian nearshore, using the results provided by numerical models. The Romanian coastal environment is located in the western side of the Black Sea, the more energetic part of the sea, an area with heavy maritime traffic and various offshore operations. Information about the wind and wave climate in the Romanian waters is mainly based on observations at Gloria drilling platform (70 km from the coast). As regards the waves, the measurements of the wave characteristics are not so accurate due to the method used, being also available for a limited period. For this reason, the wave simulations that cover large temporal and spatial scales represent an option to describe better the wave climate. To assess the wind climate in the target area spanning 1992–2016, data provided by the NCEP-CFSR (U.S. National Centers for Environmental Prediction - Climate Forecast System Reanalysis) and consisting in wind fields at 10m above the sea level are used. The high spatial and temporal resolution of the wind fields is good enough to represent the wind variability over the area. For the same 25-year period, as considered for the wind climate, this study characterizes the wave climate from a wave hindcast data set that uses NCEP-CFSR winds as input for a model system SWAN (Simulating WAves Nearshore) based. The wave simulation results with a two-level modelling scale have been validated against both in situ measurements and remotely sensed data. The second level of the system, with a higher resolution in the geographical space (0.02°×0.02°), is focused on the Romanian coastal environment. The main wave parameters simulated at this level are used to analyse the wave climate. The spatial distributions of the wind speed, wind direction and the mean significant wave height have been computed as the average of the total data. As resulted from the amount of data, the target area presents a generally moderate wave climate that is affected by the storm events developed in the Black Sea basin. Both wind and wave climate presents high seasonal variability. All the results are computed as maps that help to find the more dangerous areas. A local analysis has been also employed in some key locations corresponding to highly sensitive areas, as for example the main Romanian harbors.

Keywords: numerical simulations, Romanian nearshore, waves, wind

Procedia PDF Downloads 314