Littérature scientifique sur le sujet « Maximum temperature location »
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Articles de revues sur le sujet "Maximum temperature location"
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Mupangwa, Walter, Lovemore Chipindu, Bongani Ncube, Siyabusa Mkuhlani, Nascimento Nhantumbo, Esther Masvaya, Amos Ngwira, Mokhele Moeletsi, Isaiah Nyagumbo et Feyera Liben. « Temporal Changes in Minimum and Maximum Temperatures at Selected Locations of Southern Africa ». Climate 11, no 4 (6 avril 2023) : 84. http://dx.doi.org/10.3390/cli11040084.
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Agriculture is threatened by ever increasing temperatures and this trend is predicted to continue for the near and distant future. The negative impact of rising temperatures on agri-food systems is also compounded by the erratic and highly variable rainfall in most parts of southern Africa. Minimum and maximum temperatures’ variability and trend analysis were undertaken using daily time series data derived from 23 meteorological stations spread across Malawi, Mozambique, South Africa and Zimbabwe. The modified Mann–Kendall and Theil–Sen slope models were used to assess temperature trends and their magnitudes. Temperature varied with location and minimum temperature was more variable than maximum temperature. Semi-arid regions had higher variation in minimum temperature compared to humid and coastal environments. The results showed an upward trend in minimum (0.01–0.83 °C over a 33–38 year period) and maximum (0.01–0.09 °C over a 38–57 year period) temperatures at 9 and15 locations, respectively. A downward trend in minimum temperature (0.03–0.20 °C over 38–41 years) occurred in South Africa at two locations and Dedza (Malawi), while a non-significant decline in maximum temperature (0.01 °C over 54 years) occurred at one location in coastal dry sub-humid Mozambique. The results confirm the increase in temperature over 33–79 years, and highlight the importance of including temperature when designing climate change adaption and mitigation strategies in southern Africa and similar environments.
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Lekea, Angella, et Wynand J. vdM Steyn. « Performance of Pavement Temperature Prediction Models ». Applied Sciences 13, no 7 (24 mars 2023) : 4164. http://dx.doi.org/10.3390/app13074164.
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Appropriate asphalt binder selection is dependent on the correct determination of maximum and minimum pavement temperatures. Temperature prediction models have been developed to determine pavement design temperatures. Accordingly, accurate temperature prediction is necessary to ensure the correct design of climate-resilient pavements and for suitable pavement overlay design. Research has shown that the complexity of the model, input variables, geographical location among others affect the accuracy of temperature prediction models. Calibration has also proved to improve the accuracy of the predicted temperature. In this paper, the performance of three pavement temperature prediction models with a sample of materials, including asphalt, was examined. Furthermore, the effect of calibration on model accuracy was evaluated. Temperature data sourced from Pretoria were used to calibrate and test the models. The performance of both the calibrated and uncalibrated models in a different geographical location was also assessed. Asphalt temperature data from two locations in Ghana were used. The determination coefficient (R2), Variance Accounted For (VAF), Maximum Relative Error (MRE) and Root Mean Square Error (RMSE) statistical methods were used in the analysis. It was observed that the models performed better at predicting maximum temperature, while minimum temperature predictions were highly variable. The performance of the models varied for the maximum temperature prediction depending on the material. Calibration improved the accuracy of the models, but test data relevant to each location ought to be used for calibration to be effective. There is also a need for the models to be tested with data sourced from other continents.
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Amelia, Afritha, Bakti Viyata Sundawa, Roslina et Rahimah Abdul Rahman. « Implementation of Environmental Parameter Control System in Green House to Increase Vegetable Production ». International Journal of Research in Vocational Studies (IJRVOCAS) 4, no 4 (31 janvier 2025) : 01–06. https://doi.org/10.53893/ijrvocas.v4i4.308.
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The use of green houses in plant cultivation is one way to approach optimal conditions for plant growth. Green houses are generally useful for protecting plants from extreme air temperatures. This requires further study of the smart features that will be built to support the concept of greenhouse agriculture. The development of automation technology is expected to help the monitoring system of parameters that affect the production of vegetable crops such as air temperature, and air humidity. These parameters will be monitored remotely using the Internet of Things (IoT) method. Based on the measurement results from the location at POLMED campus. For Medan Selayang the maximum temperature is 26.4oC and humidity is 68.8%. For the location in Medan Johor the maximum temperature is 25.4oC and humidity is 68.1%. For Medan Baru location, the maximum temperature is 25.1oC and humidity is 68.3%. For Medan Helvetia location, the maximum temperature was 24.7oC and humidity was 69%. Based on the test results, the temperature and humidity parameters can be monitored remotely by 106.4 km via the internet.
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TSIALTAS, J. T., et N. MASLARIS. « The effect of temperature, water input and length of growing season on sugar beet yield in five locations in Greece ». Journal of Agricultural Science 152, no 2 (7 janvier 2013) : 177–87. http://dx.doi.org/10.1017/s0021859612000998.
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SUMMARYFrom 1999 to 2006, 36 field experiments were conducted in five sugar beet growing areas in Greece (Larissa, Plati, Serres, Xanthi and Orestiada) to monitor yield. Locations differed significantly regarding thermal variables during the growing season with Xanthi having the most favourable thermal conditions (Tmax, average daily maximum temperature;Tmean, average daily mean temperature; GDD, growing degree days) for sugar beet growth. From early June to the end of the harvesting campaign, successive harvests were conducted. Over the years, fresh root weight and sugar yield at the last harvest of the season (FRWLH, SYLH) did not differ significantly among locations. Also, there were no significant differences among locations regarding GDD for maximum FRW and SY (GDDMFRW, GDDMSY), with the means over location estimated at 2639·9 and 2792·5 °C, respectively. Days after seeding (DAS) necessary for maximum yield (DASMFRW, DASMSY, respectively) differed among locations, with the longest period (DASMFRW206·4 days, DASMSY: 204·5 days) occurring in the northernmost location (Orestiada). Means for DASMFRWand DASMSYat the five locations were estimated at 190·4 and 188·9·days, respectively. Excluding Xanthi and combining the remaining locations, FRWLHand SYLHwere negatively correlated with the average temperatures (Tmean,TmaxandTmin, daily minimum temperature) over the growing season. The opposite was evident for Xanthi where sugar beet was grown under sub-optimal temperatures. The optimum meanTmaxof the five locations was estimated at 25·5 and 25·1 °C for FRWLHand SYLH, respectively. Elongation of the growing season, by means of early sowing, would increase yield by decreasing average temperatures (Tmean,Tmax) over the growing season in locations with the highest recorded temperatures (Larissa, Plati, Serres and Orestiada). In Xanthi, the projected temperature increase, as a result of climate change, is expected to have a positive effect on yields.
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Weinberg, Michael C. « On the location of the maximum homogeneous crystal nucleation temperature ». Journal of Non-Crystalline Solids 83, no 1-2 (juin 1986) : 98–113. http://dx.doi.org/10.1016/0022-3093(86)90060-8.
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Hermansson, Åke. « Simulation Model for Calculating Pavement Temperatures Including Maximum Temperature ». Transportation Research Record : Journal of the Transportation Research Board 1699, no 1 (janvier 2000) : 134–41. http://dx.doi.org/10.3141/1699-19.
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A simulation model has been developed to calculate the temperatures of asphalt concrete during summer. Input data to the simulation model are hourly values for solar radiation, air temperature, and wind velocity. Longwave radiation incident to and outgoing from the pavement surface is calculated from the air and pavement surface temperatures, respectively. The portion of the incident shortwave radiation absorbed by the pavement surface is calculated from the albedo of the surface. By means of a finite difference approximation of the heat transfer equation, the temperatures are calculated under the surface. Apart from radiation and heat transfer, convection losses from the pavement surface are also calculated depending on wind velocity, air temperature, and surface temperature. The formulas used for the calculation of radiation and the simulation model as a whole are validated by comparison with measurements, showing good agreement. A method for the calculation of direct solar radiation from a clear sky, at an arbitrary location and time, is used to create input data to the simulation model in order to calculate maximum pavement temperatures. The formulas used with Superpave to calculate maximum pavement temperatures are based on the assumption that there is an equilibrium when a maximum temperature is reached. Such an equilibrium assumption can be strongly questioned, and its consequences are discussed.
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DeGaetano, Arthur T., Keith L. Eggleston et Warren W. Knapp. « A Method to Estimate Missing Daily Maximum and Minimum Temperature Observations ». Journal of Applied Meteorology 34, no 2 (1 février 1995) : 371–80. http://dx.doi.org/10.1175/1520-0450-34.2.371.
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Abstract A method to estimate missing daily maximum and minimum temperatures is presented. Temperature estimates are based on departures from daily temperature normals at the three closest stations with similar observation times. Although applied to Cooperative Observer Network stations in the northeastern United States, the approach can be used with any network of stations possessing an adequate station density and period of record. Generally, 75% of the estimates for both daily maximum and minimum temperature are within 1.7°C of the observed value. Median absolute differences between estimated and observed minimum temperatures, however, tend to be greater than those associated with maximum temperatures. For minimum temperatures, median absolute differences are approximately 1.0°C, whereas for maximum temperatures these differences are near 0.5°C. The accuracy of the estimates is independent of observation time, geographic location, and observed temperature but is influenced somewhat by station density.
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Rattigan, K., et SJ Hill. « Relationship between temperature and flowering in almond : effect of location ». Australian Journal of Experimental Agriculture 27, no 6 (1987) : 905. http://dx.doi.org/10.1071/ea9870905.
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A model for the prediction of flowering date in almond requires estimates of the chilling and heat sum requirements. We estimated hourly temperatures from daily minimum and maximum temperatures. A continuous function relating hourly temperature to rate of chilling was used to calculate daily chill unit accumulations. Heat sums were measured as growing-degree-hours: the linear accumulation of hourly temperatures above a threshold temperature. Our model was tested with estimates derived from data obtained at 1 French and 2 Australian locations. The results indicate that estimates derived from data at a single location can be successfully used for other locations with different climates. The accuracy of flowering date prediction generally improves as the number of locations and years of data on which it is based increase. The predictions for the cultivars Mission and Nonpareil were within 5 days of the observed dates in 73 and 88% respectively of the locations-years examined. We concluded that the chilling requirement in almond is (mean � s.e.) 284 � 33 chill units and 3 groups of cultivars can be identified with respect to heat sum requirement in the ranges 5300-6300; 6800-7700 and 8200-8900 degree hours above 4.5�C.
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Guo, Hanwen, Zhengyuan Yang, Peiyao Zhang, Yunji Gao et Yuchun Zhang. « Experimental Investigation on Fire Smoke Temperature under Forced Ventilation Conditions in a Bifurcated Tunnel with Fires Situated in a Branch Tunnel ». Fire 6, no 12 (17 décembre 2023) : 473. http://dx.doi.org/10.3390/fire6120473.
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In this work, a number of experiments were conducted in a reduced scale bifurcation tunnel with a ratio of 1:10 to explore the influence of the position of longitudinal fires (placed in branch tunnel) on smoke temperature profile under forced ventilation. Three heat release rates, six ventilation velocities, and three fire locations were considered. The main findings are summarized below, as follows: The temperature of smoke downstream of the main tunnel decreases with the rate of ventilation and longitudinal fire location. In contrast, the smoke temperature downstream of the fire source inside the branch tunnel drops with the ventilation velocity; the maximum temperature of the flame under the ceiling of the tunnel rises with longitudinal fire location. The dimensionless longitudinal smoke temperatures downstream of the main tunnel decrease exponentially with longitudinal distance, and the same observation is found in the branch tunnel. The attenuation coefficient k in the main tunnel increases with longitudinal ventilation velocity according to a power law but does not change significantly with longitudinal fire locations. However, the exponential coefficient k′ in the branch tunnel decreases linearly with ventilation velocity, whereas it increases with longitudinal fire location inside the branch tunnel. Lastly, modified models are established for estimating the longitudinal profile of temperatures downstream of the main tunnel and branch tunnel, where the influence of the rate of ventilation and location of the fire are taken into account.
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Nasher, NM Refat, et MN Uddin. « Maximum and Minimum Temperature Trends Variation over Northern and Southern Part of Bangladesh ». Journal of Environmental Science and Natural Resources 6, no 2 (11 février 2015) : 83–88. http://dx.doi.org/10.3329/jesnr.v6i2.22101.
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Temperature is one of the pivotal climatic variables in our world climate literature. In the present study monthly, seasonal and yearly highest maximum and lowest minimum temperatures of two cities were analyzed. Mann-Kendall test and Sens Slope Estimator were used to determine the trend and slope magnitude. Chittagong, as the coastal city and Rajshahi, as Barind track were selected as a study area due to its respective geographical location. Such types of data of 52 years for Chittagong as well as 48 years for Rajshahi were collected from Bangladesh Meteorological Department (BMD). Monthly highest maximum and lowest minimum temperature data from 1950-2002 for Chittagong and 1964-2012 for Rajshahi were used for analysis. In Rajshahi, significant rising trends were found in highest maximum post-monsoon temperature, lowest minimum monsoon temperature and highest maximum temperature from July to October, June and August for lowest minimum temperature. Falling trends were found in annual highest maximum and lowest minimum temperatures, pre-monsoon highest maximum temperature, lowest minimum winter temperature and January lowest minimum temperature. For Chittagong, significant increasing trends found in post-monsoon highest maximum temperature, June to December highest maximum temperature except July and December lowest minimum temperature. No significant decreasing trend was found in Chittagong.DOI: http://dx.doi.org/10.3329/jesnr.v6i2.22101 J. Environ. Sci. & Natural Resources, 6(2): 83-88 2013
Thèses sur le sujet "Maximum temperature location"
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Alcantara, Manzueta Santiago Elias. « Etude de la sécurité thermique d'un réacteur chimique : approche par contrôle de la température ». Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMIR45.
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Dans cette thèse, ma contribution se concentre sur le développement d’une méthodologie pour le contrôle intelligent de la température maximale dans un réacteur tubulaire. Ces expressions sont dérivées d'un modèle analytique précédemment publié par (Vernières-Hassimi et al., 2016) et ont été adaptées et simplifiées pour leur application dans ce contexte. La première expression analytique développée concerne le calcul de la position de la température maximale de réaction, un paramètre fondamental pour la sécurité dans les réacteurs tubulaires. Cette expression permet d'analyser le comportement du point chaud à l'intérieur du réacteur et comment sa position varie en fonction des changements dans les paramètres d'entrée, ce qui facilite une sélection plus appropriée des configurations opérationnelles. De plus, cette expression s'intègre avec la formule précédemment développée par (Vernières-Hassimi et al., 2016). La deuxième expression est le résultat d'une résolution de l'équation originale, par laquelle on calcule la température de refroidissement du réacteur. Cette expression est particulièrement utile pour déterminer la température de refroidissement face à des variations des conditions opérationnelles, fournissant ainsi un outil efficace pour la gestion thermique du systèmeIn this thesis, my contribution focuses on the development of a methodology for intelligent control of the maximum temperature in a tubular reactor. These expressions are derived from an analytical model previously published by (Vernières-Hassimi et al., 2016) and have been adapted and simplified for their application in this context. The first analytical expression developed concerns the calculation of the position of the maximum reaction temperature, a fundamental parameter for safety in tubular reactors. This expression allows for the analysis of the behaviour of the hot spot inside the reactor and how its position varies according to changes in input parameters, which facilitates a more appropriate selection of operational configurations. Furthermore, this expression integrates with the formula previously developed by (Vernières-Hassimi et al., 2016). The second expression results from a resolution of the original equation, through which the reactor's cooling temperature is calculated. This expression is particularly useful for determining the cooling temperature in response to variations in operational conditions, thus providing an effective tool for the thermal management of the system
Chapitres de livres sur le sujet "Maximum temperature location"
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Xie, Jiaqiang, et Wei Kuang. « Simulation of the Mixing Performance of an Optimized Air Injector ». Dans Lecture Notes in Mechanical Engineering, 1131–42. Singapore : Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-97-7887-4_99.
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Abstract The trim air system is an important system for realizing the temperature control of the flight deck and passenger cabin of commercial aircraft. The trim air duct is designed to bleed the high-temperature air to mix the cold air from the upstream of the refrigeration components in order to satisfy the independent temperature requirements of each area of the flight deck and passenger cabin. If the cold air and hot air mixing situation was poor, downstream temperature sensor layout location there is still a more serious hot and cold air stratification, the measured value is more difficult to reflect the average temperature of the mixed air, thus affecting the accuracy of the air conditioning system temperature regulation. In order to improve the mixing efficiency of the trim hot bleed air and ventilation air, this paper proposes an optimized trim air injector based on typical configuration, then models and calculates two configurations of the trim injector using three-dimensional simulation to obtain the fluid flow and temperature distribution characteristics under different conditions. In this paper, the MAX temperature difference, the Surface standard deviation of temperature, the Surface uniformity of temperature and other parameters are also utilized to model and calculate the air flow and temperature distribution characteristics of the two configurations of the trim injector. The mixing effects of the two trim injectors were analyzed and evaluated. The results show that, after optimization, the radial high-speed thermal jet can effectively improve the perturbation and mixing between the hot and cold fluids after the hot bleed air passes through the inflow nozzle; compared with the typical configuration, the optimized configuration has a lower maximum temperature difference of about 67% and a lower standard deviation of temperature of 71% in each cross-section. The surface temperature uniformity coefficient of the optimized configuration is closer to 1 in each cross-section, and the temperature stratification effect and mixing effect are better than that of the typical configuration.
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Iyiola-Tunji, Adetunji Oroye, James Ijampy Adamu, Paul Apagu John et Idris Muniru. « Dual Pathway Model of Responses Between Climate Change and Livestock Production ». Dans African Handbook of Climate Change Adaptation, 523–62. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_230.
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AbstractThis chapter was aimed at evaluating the responses of livestock to fluctuations in climate and the debilitating effect of livestock production on the environment. Survey of livestock stakeholders (farmers, researchers, marketers, and traders) was carried out in Sahel, Sudan, Northern Guinea Savannah, Southern Guinea Savannah, and Derived Savannah zones of Nigeria. In total, 362 respondents were interviewed between April and June 2020. The distribution of the respondents was 22 in Sahel, 57 in Sudan, 61 in Northern Guinea Savannah, 80 in Southern Guinea Savannah, and 106 in Derived Savannah. The respondents were purposively interviewed based on their engagement in livestock production, research or trading activities. Thirty-eight years’ climate data from 1982 to 2019 were obtained from Nigerian Metrological Agency, Abuja. Ilela, Kiyawa, and Sabon Gari were chosen to represent Sahel, Sudan, and Northern Guinea Savannah zone of Nigeria, respectively. The data contained precipitation, relative humidity, and minimum and maximum temperature. The temperature humidity index (THI) was calculated using the formula: THI = 0.8*T + RH*(T-14.4) + 46.4, where T = ambient or dry-bulb temperature in °C and RH=relative humidity expressed as a proportion. Three Machine Learning model were built to predict the monthly minimum temperature, maximum temperature, and relative humidity respectively based on information from the previous 11 months. The methodology adopted is to treat each prediction task as a supervised learning problem. This involves transforming the time series data into a feature-target dataset using autoregressive (AR) technique. The major component of the activities of livestock that was known to cause injury to the environment as depicted in this chapter was the production of greenhouse gases. From the respondents in this chapter, some adaptive measures were stated as having controlling and mitigating effect at reducing the effect of activities of livestock on the climate and the environment. The environment and climate on the other side of the dual pathway is also known to induce stress on livestock. The concept of crop-livestock integration system is advocated in this chapter as beneficial to livestock and environment in the short and long run. Based on the predictive model developed for temperature and relative humidity in a sample location (Ilela) using Machine Learning in this chapter, there is need for development of a web or standalone application that will be useable by Nigerian farmers, meteorological agencies, and extension organizations as climate fluctuation early warning system. Development of this predictive model needs to be expanded and made functional.
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Obiko, Japheth, et Fredrick Madaraka Mwema. « Stress and Strain Distribution in the Upsetting Process ». Dans Handbook of Research on Advancements in Manufacturing, Materials, and Mechanical Engineering, 288–301. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-4939-1.ch013.
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Numerical simulation of metal flow behaviour was studied using DeformTM3D software. The simulation process was done on X20 steel taken from the software database at 1073-1273K temperature, 10mm/s die speed, and 67% height reduction. From the simulation results, forging load, damage, and stress/strain distributions were obtained. The results show that the forging load increased with a decrease in temperature or decreased with an increase in temperature. The maximum damage values increased as the temperature increased. The obtained maximum damage values were 0.42 (1073K), 0.43 (1173K), and 0.45 (1273K). The damage distribution was inhomogeneous in the deformed cylinder. The stress/strain distributions were inhomogeneous in the deformed cylinder. The location of the maximum strain was at the centre of the deformed cylinder while the maximum stress occurred at the die-cylinder contact surfaces. The study showed that flow stress behaviour can be predicted using finite element method. This shows the feasibility of applying the finite element analysis to analyse the forging process.
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Murray, Elanor, Ying Zhou, Peter Slater, Roger Smith, Pooja Goddard et Helen Steele. « A molecular dynamics study of helium clustering in high temperature plutonium dioxide ». Dans Environmental Radiochemical Analysis VII, 86–94. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/9781837670758-00086.
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The behaviour of helium in high temperature PuO2 has been examined via molecular dynamics calculations. In an initially defect free lattice helium is mobile at temperatures above 1500 K, making inter-site hops via thermally generated oxygen vacancies. Over a 5 ns time scale, helium clustering does not occur until above 2400 K, at which temperature temporary plutonium Frenkel pairs are possible. The created Pu vacancy can be pinned by either oxygen vacancies (as a Schottky trio), or by the addition of extra He before Pu recombination occurs. This site then acts as a helium cluster seed location to which further He can be attracted. The time evolution of helium clusters was analysed and a mean He:vacancy ratio of 0.75:1 was obtained. Throughout the dynamical evolution of the cluster, a He:vacancy ratio below 1:1 was always found in contrast to previous static calculations which predicted a theoretical maximum ratio of 3.5:1.
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Belhachmi, Zakaria, Amel Ben Abda, Belhassen Meftahi et Houcine Meftahi. « Optimal Heat Distribution Using Asymptotic Analysis Techniques ». Dans Optimization Problems in Engineering [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97371.
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In this chapter, we consider the optimization problem of a heat distribution on a bounded domain Ω containing a heat source at an unknown location ω⊂Ω. More precisely, we are interested in the best location of ω allowing a suitable thermal environment. For this propose, we consider the minimization of the maximum temperature and its L2 mean oscillations. We extend the notion of topological derivative to the case of local coated perturbation and we perform the asymptotic expansion of the considered shape functionals. In order to reconstruct the location of ω, we propose a one-shot algorithm based on the topological derivative. Finally, we present some numerical experiments in two dimensional case, showing the efficiency of the proposed method.
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Bhattacharjee, Saurav, et Sabiha Raiyesha. « Analysis of Arima Model for Weather Forecasting in the Assam District ». Dans Critical Approaches to Data Engineering Systems and Analysis, 50–63. IGI Global, 2024. http://dx.doi.org/10.4018/979-8-3693-2260-4.ch004.
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Weather forecasting is a scientific method that involves the prediction of atmospheric conditions at a specific geographic location. The increased volatility over the last decade is owing to an enormous rise in water used for irrigation application throughout agricultural area, much of which evaporates, necessitating accurate forecasting in order to take essential safeguards. In this chapter, an attempt is made to predict the average temperature and maximum temperature through machine learning models. The daily temperature data from 1970 to 2022 were collected from the National Centre of Environmental Information (NCEI). The ARIMA model is used to predict the weather data sets of Tezpur, Assam. Previous conventional models are insufficient to predict forecasting precisely. So statistical models and auto-regressive models are programmed and compared.
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Kumar, Vinay, et Robert Ross. « Recent Changes in Temperature and Maximum Snow Cover Days over the Northern Hemisphere with a Focus on Alaska ». Dans Global Warming - A Concerning Component of Climate Change [Working Title]. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.1004003.
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One aspect of climate variability is the shift in seasonal change, with a given season arriving early or late. However, this shift in season is location-dependent and affects local ecology. Over subpolar regions, the change in temperature is very much associated with the regional and local variability of snow-caps, sea ice near the pole, pole-ward transportation of heat, cloud cover, and wind circulation. Based on a 36-year analysis of skin temperature, we found that the lowest temperature occurred in March rather than in February. Additionally, the maximum snow cover day has shifted from March 12 to March 17 in the last 3 to 4 decades. A plausible reason for the late accumulation of ice/snow over the Arctic/Alaskan region may be due to the multi-scale interactions between multi-decadal oscillations, for example, North Atlantic Oscillations (NAO) and climate change.
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Singh, Kasturi. « Perspective Chapter : The Coastal Migration of the Locations of Tropical Cyclone Rapid Intensification over the North Indian Ocean ». Dans Sustainable Development. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.114930.
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The migration of maximum intensity poleward is triggering a shift in the rapid intensification (RI) locations of tropical cyclones (TC) towards the coast of ocean-rim countries. The study investigates changes in the distribution of locations of RI during the pre-monsoon and post-monsoon seasons in recent warming climate scenarios over the North Indian Ocean (NIO) basin. Over the Bay of Bengal (BOB), the percentage of annual RI TC frequency exhibits a stable or slightly decreasing trend (20–100%), contrasting with a notable surge (50–100%) over the Arabian Sea (AS) in recent years. The distribution of RI TC location gradient is meridional during the pre-monsoon season and is confined zonally below 15°N during the post-monsoon season over BOB. The corresponding locations over AS are confined between 10°N–15°N and 12°N–17°N latitudinal regions. An inverse relation between the simultaneous rise in SST and RH550 is evident during the pre-monsoon season, while the relation fails during the post-monsoon season over BOB. While sea surface temperature and mid-tropospheric relative humidity play a crucial role in RI, the observed changes in tropospheric vertical wind shear patterns and upper-level divergence alignment in current climate conditions are identified as influential factors shaping the distribution of RI location over BOB and AS.
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« Pacific Salmon : Ecology and Management of Western Alaska’s Populations ». Dans Pacific Salmon : Ecology and Management of Western Alaska’s Populations, sous la direction de David A. Beauchamp. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874110.ch5.
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<em>Abstract.</em>—Size-selective mortality is a dominant variable regulating the dynamics of salmon populations. Body size, growth rate, and energy state during one life stage influence survival during that and subsequent life stages. Therefore, simultaneously examining allometric processes, foraging, and thermal constraints on growth within and among life stages can provide a powerful analytical framework for identifying critical periods and sizes during the life cycle of salmon, and for understanding the processes that contribute to the specific ecological bottlenecks confronting different species or stocks of salmon. A bioenergetics model was used to simulate generalized growth responses to a factorial combination of body size, daily feeding rate, and prey energy density over a continuous range of temperatures (0–24oC). The results of these simulations indicated that: 1) smaller salmon benefit from higher potential scope for growth or activity than larger salmon, based on the different allometric relationships for maximum consumption, metabolism, and waste; 2) optimal temperatures for growth decline with increasing body size; 3) optimal temperatures for growth also decline as daily rations decline; 4) thermal tolerances (temperature thresholds beyond which weight loss will occur) also shift to cooler temperatures for larger salmon and when ration sizes decline; 5) increasing the composite energy density of the diet can increase both optimal growth temperature, and thermal tolerance, especially at larger body sizes; 6) after spawners enter freshwater, the amount of energy and days available to migrate, and successfully spawn at a given upstream location was very sensitive to ambient river temperature, and the swimming speed required to reach the spawning grounds. When placed in the context of climate variability, seasonal shifts in temperature, and food availability, these simulations suggest that growth will be more frequently limited by feeding rate (prey availability) and prey quality than by temperature, especially for smaller, younger life stages. Larger salmon should be more sensitive to temperature change, but reductions in optimal growth temperature and thermal tolerance would be magnified for all life stages, if either feeding rate or prey quality were to be reduced. Given intense size-selective mortality during one or more early life stages, this simulation framework could be adopted to identify the key factors limiting growth to critical sizes during critical periods in the life cycle of specific salmon stocks.
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Duffus-Scott, A. B., L. A. Machado-Rodríguez, E. A. Álvarez-García et C. Patiño-Carachure. « Causes of cracking in the turbine housings of a turbocharger ». Dans Innovative Applications in Sustainable Energy and Environment, 46–55. ECORFAN, 2024. https://doi.org/10.35429/h.2024.13.46.55.
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Temperature variation in turbocharger casings of generator sets generates shocks and thermal fatigue that cause cracks in different areas, with permissible limits depending on the direction and location. This study analyzes the microstructure and chemical composition of nodular cast iron castings manufactured under ASTM A 536 and GOST3443-87 standards, using metallographic techniques and emission spectroscopy. With visual inspection and penetrating liquids, the types of cracks and their orientations are examined. The maximum amplitude of the thermal stress generated during the thermal shock was determined using MATLAB software, considering that for a minimum stress concentration factor (kf=1), the thermal stress amplitude is 560 MPa, exceeding the design limit of 210 MPa, which explains the appearance of transverse and longitudinal cracks. Transverse cracks show a higher thermal stress concentration factor than longitudinal cracks.
Actes de conférences sur le sujet "Maximum temperature location"
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Watjen, J. I., M. T. Schifano et M. N. Sexton. « Maximum Condensable Pressure in a Sealed Container With Arbitrary Temperature Distribution ». Dans ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23142.
Texte intégralRésumé :
Abstract Pressure vessels and sealed canisters are designed to maintain seal integrity under a maximum internal pressure. When the temperature inside the canister rises, the internal pressure rises accordingly. The presence of condensable liquid-vapor mixtures can create a strong relationship between the pressure and temperature. An isothermal container admits a straightforward thermodynamic pressure calculation; however, large temperature gradients inside the container require complex multiphase conjugate heat transfer calculations to predict accurate pressures. A simplified prediction using the peak internal temperature to find the saturated pressure of the condensable fluid may introduce unrealistic pressures when significant fluid mass exists in a cooler location of the container. This work presents methodology to calculate the pressure of a condensable fluid in a sealed container with large internal temperature differences using a two-temperature approach to predict saturated boiling and superheating of the vapor phase. An arbitrary temperature distribution allows for pressure calculations by considering the expected location of the liquid mass and the peak internal temperature. An enthalpy balance provides the effects of the temperature distribution and the peak pressure condition is easily predicted using the proposed method. This work provides a means to calculate the maximum internal pressure of a sealed container with a condensable fluid without the need for complex multiphase computer modeling.
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Peng, Hao, Yuwen Zhang et P. Frank Pai. « Uncertainty Analysis of Solid-Liquid-Vapor Phase Change of a Metal Particle Subject to Nanosecond Laser Heating ». Dans ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-85555.
Texte intégralRésumé :
Effects of uncertainties of various parameters, including laser fluence, diameter of metal powder articles, laser pulse width and initial temperature of metal particles, on solid-liquid-vapor phase change processes of metal particles under nanosecond laser heating are investigated in this paper. A systematic approach of simulating phase change with uncertain parameters are presented and a sample-based stochastic model are established to investigate the influence of different uncertain parameters on maximum surface temperature of metal particles, maximum solid-liquid interface location, maximum liquid-vapor interface location, maximum saturation temperature and maximum recoil pressure, and time needed to reach maximum solid-liquid interface location. The results show that the mean value and standard deviation of laser fluence have dominant effects on all output parameters.
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Al Awadhi, Ibrahim, Ashok Sharma et Twana Karim. « Practicing Sustainability in Remote Location ». Dans International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-22686-ms.
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Abstract Objective/Scope Effective electrical and instrument control system is required for efficient operation of pipeline network. These equipment are kept in unmanned shelter with necessary cooling, as ambient temperature can go upto 54°C vs designed of 40°C. Pipelines and supply network often run through remote areas where usually no power supply is available. This puts heavy challenges to cooling inside shelters. This paper presents a unique approach adopted to enhance the shelter cooling performance in remote locations. Methods, Procedures, Process Conventionally shelter in remote area are Passive cooled shelter (PCS) where water in the exchanger is cooled by using lowest night ambient air. This water is circulated inside the shelter in closed circuit which cools the space by natural convection. High inside temperature (45°C) was recorded in some existing PCS. To assess reasons for high temperature, performance of PCS and heat dissipations of installed equipment against design values were evaluated. Furthermore, survey was performed for ambient and inside temperature during summer peak time instead of assuming ambient temperature of 54°C. Accordingly, the impact of maximum temperature on instrument was evaluated. Results, Observations & Conclusions Study concluded high inside temperature in PCS was due to high heat dissipation and external opening for ventilation in battery room. Conventionally reduction in maximum temperature inside PCS can be carried out by increasing the capacity of installed external exchangers from existing 300 W/C to 600 W/C. Further benefits can be achieved by installing small fans next to the internal water tank and installing breather diaphragms with filter in external openings to reduce the heat input from outside. However, study concluded that with all this, minimum temperature inside PCS can be reduced to 42°C vs required 40°C as all installed equipment are designed to operate at max 40°C. This is due to high lowest ambient temperature during peak summer (36°C) Due to remote location and non-availability of electric power, unique approach of additional cooling using Solar Hybrid A/C system was proposed without battery charger. Study concluded installing Hybrid Solar A/C system without battery charger can be operated during the summer peak time for period of 6 hours per day can bring down the inside temperature below 35°C throughout the year. Proposed solution is now successfully implemented in existing PCS and performance is found satisfactory during peak summer condition. Novel/Additive Information There is several PCS with similar issues and this unique approach of installing 24V DC Hybrid Solar A/C system is now being adopted in other PCS shelter which will support ADNOC Way by sustaining safe network operation and 100% HSE. There are large network of pipeline running in remote locations across the world where power availability is a concern and limit were above approach can be followed to realize larger benefits.
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Schmitz, Walter, et Albert Koster. « Air Ingress and Corrosion Potential for PBMR Direct Cycle ». Dans Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58150.
Texte intégralRésumé :
The possibility of fuel and graphite degradation due to chemical attack is a perennial issue for HTR’s. For the direct cycle used in the PBMR design, only air ingress is a problem that merits serious attention. Initially, and as reported at a previous conference, investigation of the problem was tackled by assuming worst case conditions for a break at the core outlet pipe to determine what the grace time would be, before counter measures need be taken. The current work identified worst case break positions, quantifying air ingress rates, assuming a Guillotine break. These calculations include first order corrosion reactions in the bottom reflector and the core. Taking the worst possible large break location and the maximum initial air ingress as a determinant, a period of 24 hours was determined to be sufficient to prevent both serious fuel and core structure degradation. The acceptability of the extent of corrosion will be determined by the Safety Analysis Report (SAR), which is under preparation. However, it was realized that a more realistic specification and analysis of the problem was required to enable design decisions to be made, and a more detailed model of the break and the Main Power System (MPS) cavities was developed. This includes the maximum movement of large piping postulating a Double Ended Guillotine Break (DEGB) at worst possible locations. Further calculations on the improved model are described that investigate the influence of various pipe separations i.e. 50 mm and 500 mm at the turbine inlet. A strong correlation between the opening size and total core corrosion rate was confirmed. The simulation also established an approximate duration for air to be expelled to stop further ingress and the volume flow requirements for the inert gas system using helium or nitrogen.
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Guo, Zhou, David L. Rhode et Fred M. Davis. « Computed Eccentricity Effects on Turbine Rim Seals at Engine Conditions With a Mainstream ». Dans ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-031.
Texte intégralRésumé :
A previously verified axisymmetric Navier-Stokes computer code was extended for three-dimensional computation of eccentric rim seals of almost any configuration. All compressibility and thermal/momentum interaction effects are completely, included, and the temperature, pressure and Reynolds number of the mainstream, coolant stream and turbine wheel are fixed at actual engine conditions. Regardless of the seal eccentricity, both ingress and egress are found between θ = −30° and 100°. which encompasses the location of maximum radial clearance at θ = 0°. All other θ locations within the rim seal show only egress, as does the concentric basecase for all circumferential locations. Further, the maximum ingress occurs near θ = 30° for all eccentricities. This is found to produce a blade root/retainer temperature rise from the concentric case of 390 percent at 50 percent eccentricity and a 77 percent rise at 7.5 percent eccentricity. In addition, the nature of an increased eccentricity causing a decreased seal effectiveness is examined, along with the corresponding increase of cavity-averaged temperature.
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Lee, Gary, Emerson Galacio, Romy Junio, Alex Magtibay, Elijah Griffiths et Ohgeon Kwon. « Crude Furnace Floor Creep Assessment and Remaining Life Assessment due to Hot Spots ». Dans ASME 2020 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/pvp2020-21074.
Texte intégralRésumé :
Abstract Fitness for Service (FFS) assessment and remaining life assessment of the furnace floor plates in a crude charge heater where hot spots up to 500°C have been observed during operation in 2018 was undertaken as a pre assessment prior to the unit turnaround. The remaining life assessment results would provide the turnaround team with firm scope for repair in order to resintate the bottom plate and avoid discovery scope. Two Finite Element (FE) models were created to account for hotspot temperature conditions measured at November 2018 and June 2019. Each of these FE models involved successive loading conditions, so that the effects of each loading scenario could be investigated. The loading conditions were applied in steps, in the following order: 1. Gravity. 2. Temperature, modelling hotspot behaviour. 3. Creep, viscoelastic analysis. Utilising the FE models created for the two hotspot conditions, remaining life was calculated and suggested that the worst location for creep damage is near burner 2 (the maximum creep damage location of the November 2018 condition). Based on the assessment, the following recommendations are made: 1. Continue to observe and maintain temperatures below the creep temperature range (i.e. no additional hotspots are created and temperatures are not increasing). 2. Undertake creep testing from metal samples. 3. Re-inspect in 8 years at the same locations where metallographic replication was performed in September 2019.
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Hossain, Sahadat, Al Helal, Md Shamim Ahsan, Kazi Mahmud Hasan, Md Maniruzzaman et Md Enamul Kabir. « Design and Development of an Autonomous Air Quality Monitoring Drone ». Dans International Conference on Functional Materials for Energy and Manufacturing. Switzerland : Trans Tech Publications Ltd, 2024. http://dx.doi.org/10.4028/p-q4f0ty.
Texte intégralRésumé :
Air quality monitoring of any specific location is important for continuous improvement of air quality and protecting public health. We demonstrate the design and development of an autonomous copter-type air quality monitoring drone to measure the amount of CO2 and CO present in the ambient air of any desired trajectory. We also measured the temperature, pressure, and humidity of the surrounding air. The proposed low cost drone is small in size, light weight, easy to maintain, and capable of flying a long distance. In addition to autonomous control, the proposed drone can be manually controlled using a long-range remote controller. The maximum altitude of the drone from the ground control station is approximately 500 m, whereas the maximum velocity is 50 km/hour. During air quality monitoring, we collected the air quality data from 1 feet to 200 feet with 20 feet interval where the average velocity of the drone was 5.4 km/hour. We selected three different locations for data collection. Afterwards, we analyzed the collected data and determined the primary causes of variation in the CO2 and CO concentration of various locations under different altitudes. We strongly believe that, the proposed drone will be useful for collecting location specific air quality information and taking necessary actions to reduce air pollution.
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Scaletta, Brent, et Richard Green. « Critical Location Identification for Multi-Mechanistic Damage Modes Using Damage Interaction Charts ». Dans ASME Turbo Expo 2020 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14678.
Texte intégralRésumé :
Abstract Damage in gas turbine engines can accumulate from multiple damage mechanisms including creep, fatigue, and oxidation. Each damage mechanism is influenced by various parameters which typically occur during different portions of engine operation. For instance, fatigue is influenced by large stress/strain ranges that occur during startup and shutdown transient conditions while creep is affected by sustained stress and temperature at dwell conditions. In some cases, the maximum damage location for one mechanism could experience negligible contribution in damage from any other mechanism, but in most cases, there is some degree of influence from two or three mechanisms. In those instances, damage will accumulate at various rates during separate portions of operation under different damage mechanisms. Since some applications require engines to dwell for long periods of time while other applications favor more frequent cycling, every engine will accumulate damage differently at each location. Therefore, it is difficult to estimate which location is critical to durability, rendering it necessary to capture all possible critical locations so that damage can be estimated for each application. This paper suggests a method by which to visualize and select critical locations based on all possible customer use scenarios. Once critical locations are identified, a Reduced Order Model (ROM) can be generated for each point of interest and damage can be estimated and monitored using data collection. Damage mechanisms can be combined if micromechanistic affects are additive, the material response compounds, or the material properties evolve with time. Examples of each case are demonstrated. In addition, the visual representation of damage interaction allows for uncertainty to be visualized and implemented to rank location criticality.
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Hall, David E., Frank P. Incropera et Raymond Viskanta. « Jet Impingement Boiling From Circular Free-Surface Jets During Quenching Experiments ». Dans ASME 1996 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/imece1996-0066.
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Abstract This paper reports results from an experimental study of boiling heat transfer during quenching of a cylindrical copper test piece by a subcooled, circular, free-surface water jet. The disk was heated to approximately 650 °C, and as quenching occurred, transient temperature measurements were taken at discrete locations near the surface and applied as boundary conditions in a conduction model to deduce transient heat flux distributions at the surface. Results are presented in the form of heat flux distributions and boiling curves for radial locations varying from the stagnation point to ten nozzle diameters for jet velocities between 2.0 and 4.0 m/s (11,300 ≤ Red ≤ 22,600). Data for nucleate boiling in the stagnation region and spatial distributions of maximum heat flux are presented and are in good agreement with correlations developed from steady-state experiments. Spatial distributions of minimum film boiling temperatures and minimum film boiling heat fluxes are also reported and reveal a fundamental dependence on jet splashing and streamwise location.
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Li, Tianbai, Haofeng Chen, Weihang Chen et James Ure. « Ratchet Limits for a Crack in a Welded Pipe Subjected to a Cyclic Temperature Load and a Constant Mechanical Load ». Dans ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57046.
Texte intégralRésumé :
This paper presents the ratchet limit analysis of a pipe with a symmetric crack in a mismatched weld by using the extended Linear Matching Method (LMM). Two loading conditions are considered: i) a cyclic temperature load and a constant internal pressure; and ii) a cyclic temperature load and a constant axial tension. Individual effects of i) the geometry of the Weld Metal (WM), ii) the size of the crack, iii) the location of the crack and iv) the yield stress of WM on the ratchet limits, maximum temperature ranges to avoid ratchetting and limit loads are investigated. Influence functions of the yield stress of WM on the maximum temperature ranges and limit loads are generated. The results confirm the applicability of the extended LMM to the cracked welded pipe.
Rapports d'organisations sur le sujet "Maximum temperature location"
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Raymond, Kara, Laura Palacios et Evan Gwilliam. Status of climate and water resources at Big Bend National Park : Water year 2019. Sous la direction de Tani Hubbard. National Park Service, septembre 2022. http://dx.doi.org/10.36967/2294267.
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Climate and hydrology are major drivers of ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, streamflow, and water quality is central to assessing the condition of park resources. This report combines data collected on climate, groundwater, and springs at Big Bend National Park (NP) to provide an integrated look at climate and water conditions during water year (WY) 2019 (October 2018–September 2019). However, this report does not address the Rio Grande or its tributaries. Annual precipitation was higher than normal (1981–2010) for Big Bend NP at four of the five National Oceanic and Atmospheric Administration Cooperative Observer Program weather stations: 111% of normal for Chisos Basin, 122% of normal for Panther Junction, 155% of normal for Persimmon Gap, and 124% of normal for Rio Grande Village. Castolon had 88% of normal annual precipitation. All five stations had higher than normal rainfall in October and December, while rainfall totals were substantially below normal at all stations in November, February, and March. Monthly precipitation totals for April through September were more variable from station to station. Mean monthly maximum air temperatures were below normal in the fall months, with Panther Junction as much as 7.5°F below normal in October. Monthly temperatures from January through July were more variable. Temperatures in August and September were warmer than normal at every station, up to +9.4°F at Rio Grande Village and +8.7°F at Chisos Basin in July. The reconnaissance drought index values indicate generally wetter conditions (based on precipitation and evaporative demand) at Chisos Basin since WY2016 and at Panther Junction and Persimmon Gap since WY2015, except for WY2017. This report presents the manual and automatic groundwater monitoring results at nine wells. Five wells had their highest water level in or just before WY2019: Panther Junction #10 peaked at 99.94 ft below ground surface (bgs) in September 2018, Contractor’s Well peaked at 31.43 ft bgs in November 2018, T-3 peaked at 65.39 ft bgs in December 2018, K-Bar #6 Observation Well peaked at 77.78 ft bgs in February 2019, and K-Bar #7 Observation Well peaked at 43.18 ft bgs in February 2019. This was likely in response to above normal rainfall in the later summer and fall 2018. The other monitoring wells did not directly track within-season precipitation. The last measurement at Gallery Well in WY2019 was 18.60 ft bgs. Gallery Well is located 120 feet from the river and closely tracked the Rio Grande stage, generally increasing in late summer or early fall following higher flow events. Water levels in Gambusia Well were consistently very shallow, though the manual well measurement collected in April was 4.25 ft bgs—relatively high for the monitoring record—and occurred outside the normal peak period of later summer and early fall. The last manual measurement taken at TH-10 in WY2019 was 34.80 ft bgs, only 0.45 ft higher than the earliest measurement in 1967, consistent with the lack of directional change in groundwater at this location, and apparently decoupled from within-season precipitation patterns. The last water level reading in WY2019 at Oak Springs #1 was 59.91 ft bgs, indicating an overall decrease of 26.08 ft since the well was dug in 1989. The Southwest Network Collaboration (SWNC) collects data on sentinel springs annually in the late winter and early spring following the network springs monitoring protocol. In WY2019, 18 sentinel site springs were visited at Big Bend NP (February 21, 2019–March 09, 2019). Most springs had relatively few indications of natural and anthropogenic disturbances. Natural disturbances included recent flooding, drying, and wildlife use. Anthropogenic disturbances included flow modifications (e.g., springboxes), hiking trails, and contemporary human use. Crews observed one to seven facultative/obligate wetland plant...
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Kirby, Stefan M., J. Lucy Jordan, Janae Wallace, Nathan Payne et Christian Hardwick. Hydrogeology and Water Budget for Goshen Valley, Utah County, Utah. Utah Geological Survey, novembre 2022. http://dx.doi.org/10.34191/ss-171.
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Goshen Valley contains extensive areas of agriculture, significant wetlands, and several small municipalities, all of which rely on both groundwater and surface water. The objective of this study is to characterize the hydrogeology and groundwater conditions in Goshen Valley and calculate a water budget for the groundwater system. Based on the geologic and hydrologic data presented in this paper, we delineate three conceptual groundwater zones. Zones are delineated based on areas of shared hydrogeologic, geochemical, and potentiometric characteristics within the larger Goshen Valley. Groundwater in Goshen Valley resides primarily in the upper basin fill aquifer unit (UBFAU) and lower carbonate aquifer unit (LCAU) hydrostratigraphic units. Most wells in Goshen Valley are completed in the UBFAU, which covers much of the valley floor. The UBFAU is the upper part of the basin fill, which is generally less than 1500 feet thick in Goshen Valley. Important spring discharge at Goshen Warm Springs issues from the LCAU. Relatively impermeable volcanic rocks (VU) occur along much of the upland parts of the southern part of Goshen Valley. Large sections of the southwest part of the Goshen Valley basin boundary have limited potential for interbasin flow. Interbasin groundwater flow is likely at several locations including the Mosida Hills and northern parts of Long Ridge and Goshen Gap in areas underlain by LCAU. Depth to groundwater in Goshen Valley ranges from at or just below the land surface to greater than 400 feet. Groundwater is within 30 feet of the land surface near and north of Goshen, in areas of irrigated pastures and wetlands that extend east toward Long Ridge and Goshen Warm Springs, and to the north towards Genola. Groundwater movement is from upland parts of the study area toward the valley floor and Utah Lake. Long-term water-level change is evident across much of Goshen Valley, with the most significant decline present in conceptual zone 2 and the southern part of conceptual zone 1. The area of maximum groundwater-level decline—over 50 feet—is centered a few miles south of Elberta in conceptual zone 2. Groundwater in Goshen Valley spans a range of chemistries that include locally high total dissolved solids and elevated nitrate and arsenic concentrations and varies from calcium-bicarbonate to sodium-chloride-type waters. Overlap in chemistry exists in surface water samples from Currant Creek, the Highline Canal, and groundwater. Stable isotopes indicate that groundwater recharges from various locations that may include local recharge, from the East Tintic Mountains, or far-traveled groundwater recharged either in Cedar Valley or east of the study area along the Wasatch Range. Dissolved gas recharge temperatures support localized recharge outside of Goshen. Most groundwater samples in Goshen Valley are old, with limited evidence of recent groundwater recharge. An annual water budget based on components of recharge and discharge yields total recharge of 32,805 acre-ft/yr and total discharge of 35,750 acre-ft/yr. Most recharge is likely from interbasin flow and lesser amounts from precipitation and infiltration of surface water. Most discharge is from well water withdrawal with minor spring discharge and groundwater evapotranspiration. Water-budget components show discharge is greater than recharge by less than 3000 acreft/yr. This deficit or change in storage is manifested as longterm water-level decline in conceptual zone 2, and to a lesser degree, in conceptual zone 1. The primary driver of discharge in conceptual zone 2 is well withdrawal. Conceptual zone 3 is broadly in balance across the various sources of recharge and discharge, and up to 1830 acre-ft/yr of water may discharge from conceptual zone 3 into Utah Lake. Minimal groundwater likely flows to Utah Lake from zones 1 or 2.