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2022 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Luís M. Silva ◽  
Henrique P. Neiva ◽  
Mário C. Marques ◽  
Mikel Izquierdo ◽  
Daniel A. Marinho

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 184
Author(s):  
Jamila Ngondo ◽  
Joseph Mango ◽  
Joel Nobert ◽  
Alfonse Dubi ◽  
Xiang Li ◽  
...  

The evaluation of the hydrological responses of river basins to land-use and land-cover (LULC) changes is crucial for sustaining water resources. We assessed the impact of LULC changes (1990–2018) on three hydrological components (water yield (WYLD), evapotranspiration (ET), and sediment yield (SYLD)) of the Wami–Ruvu Basin (WRB) in Tanzania, using the Soil and Water Assessment Tool (SWAT). The 1990 LULC imagery was used for SWAT simulation, and imagery from 2000, 2010, and 2018 was used for comparison with modelled hydrological parameters. The model was calibrated (1993–2008) and validated (2009–2018) in the SWAT-CUP after allowing three years (1990–1992) for the warm-up period. The results showed a decrease in WYLD (3.11 mm) and an increase in ET (29.71 mm) and SYLD (from 0.12 t/h to 1.5 t/h). The impact of LULC changes on WYLD, ET, and SYLD showed that the increase in agriculture and built-up areas and bushland, and the contraction of forest led to the hydrological instability of the WRB. These results were further assessed with climatic factors, which revealed a decrease in precipitation and an increase in temperature by 1°C. This situation seems to look more adverse in the future, based on the LULC of the year 2036 as predicted by the CA–Markov model. Our study calls for urgent intervention by re-planning LULC and re-assessing hydrological changes timely.


Author(s):  
Diana Schoeppler ◽  
Annette Denzinger ◽  
Hans-Ulrich Schnitzler

Doppler shift (DS) compensating bats adjust in flight the second harmonic of the constant-frequency component (CF2) of their echolocation signals so that the frequency of the Doppler shifted echoes returning from ahead is kept constant with high precision (0.1-0.2%) at the so-called reference frequency (fref). This feedback adjustment is mediated by an audio-vocal control system which correlates with a maximal activation of the foveal resonance area in the cochlea. Stationary bats adjust the average CF2 with similar precision at the resting frequency (frest), which is slightly below the fref. Over a variety of time periods (from minutes up to years) variations of the coupled fref and frest have been observed, and were attributed to age, social influences and behavioural situations in rhinolophids and hipposiderids, and to body temperature effects and flight activity in Pteronotus parnellii. We assume that, for all DS compensating bats, a change in body temperature has a strong effect on the activation state of the foveal resonance area in the cochlea which leads to a concomitant change in emission frequency. We tested our hypothesis in a hipposiderid bat, Hipposideros armiger, and measured how the circadian variation of body temperature at activation phases affected frest. With a miniature temperature logger, we recorded the skin temperature on the back of the bats simultaneously with echolocation signals produced. During warm-up from torpor strong temperature increases were accompanied by an increase in frest, of up to 1.44 kHz. We discuss the implications of our results for the organization and function of the audio-vocal control systems of all DS compensating bats.


Author(s):  
Anna HADAMUS ◽  
Maria KOWALSKA ◽  
Martyna KĘDRA ◽  
Karolina WIADERNA ◽  
Dariusz BIAŁOSZEWSKI
Keyword(s):  

Author(s):  
Sidney Grosprêtre ◽  
Sami El Khattabi

Parkour consists of overcoming obstacles mostly in an urban landscape. Little is known regarding usual training habits and injury risks of traceurs, i.e., parkour practitioners. In this study, a 20-min survey have been fulfilled by a population of traceurs regarding training load, habits (type of warm up, physical conditioning, stretching), type of footwear, and number and type of ankle- and knee-injuries during their career. A total of 180 responses were analyzed (24.4 ± 5.9 years old, 21.7% female, 6.0 ± 3.9 years of experience). Participants reported to train 1 to 7 times per week for a mean duration of 2.2 h. 76% practiced stretching exercises. 75.6% practiced physical conditioning in addition to their parkour training (weightlifting, functional exercises). Injury rate was 1.7 per 1000 h of training, mostly ankle sprains and knee contusions. Number of injury and training load were positively correlated. The lack of physical conditioning was also a factor of injury. Knee injuries have been more frequent on participants wearing minimalist shoes. Although training appears well auto-organized and the injury rate quite low some pitfalls require attention, notably in training planning, warm-up, stretching and conditioning. Building training and coaching methods specific to parkour appears essential.


2022 ◽  
Vol 52 (1) ◽  
pp. 40-48
Author(s):  
Carolyn A. Emery ◽  
Oluwatoyosi B.A. Owoeye ◽  
Anu M. Räisänen ◽  
Kimberley Befus ◽  
Tate Hubkarao ◽  
...  

2021 ◽  
Author(s):  
Alexander Schleper ◽  
◽  
Meaghan Ewharekuko-Rempel ◽  
Trisha Scribbans ◽  
Robert Anzalone ◽  
...  

2021 ◽  
Vol 5 (1) ◽  
pp. 177-188
Author(s):  
Touvan Juni Samodra ◽  
Uray Gustian ◽  
Astiati Astiati

This study aimed to test the SOS game used as a means to warm up. SOS games were usually played on paper. The trial game consists of 3 different levels. This game could be used as a movement activity to warm up. With some modifications, this game was tested. The trial was conducted on junior high school students, totaling 40 students. The data was obtained by measuring the pulse. Pulse was measured by counting the pulse in the neck for 10 seconds. The calculation result is multiplied by 6 to determine the number of pulses per minute—data analysis by comparing the measurement results with heating criteria based on age. The results showed that the first trial had a pulse rate of 142. Based on trial with 40 samples each at level 1, 140 level 2, 143, and level 3, 143 beats per minute. All of these pulses were in the exercise pulse. So it can be recommended that this game be used for heating purposes.


2021 ◽  
pp. 5-12
Author(s):  
Myron Magats ◽  
Zenoviy Goshko ◽  
Yuriy Vagula ◽  
Anatolii Uzhva

Problem. In recent years, Ukraine has seen a sharp decline in ambient temperature, especially in the winter. Accordingly, this has a negative impact on the performance of car engines (difficult to start and prolonged warm-up), as the lion's share of private sector cars are parked in open areas and are subject to sudden temperature and humidity changes. Therefore, to partially solve this problem, our attention was focused on the air lines of the intake system of the gasoline engine, as this system is easily accessible and does not require significant design changes for its modernization. Goal. The purpose of the work is to ensure the ease of starting the gasoline engine and reduce the time to warm up. Methodology. Operation of the car in the conditions of the lowered temperatures, essentially promotes deterioration of its fuel economy. The basis of such a negative process of fuel consumption is incomplete combustion of the working mixture. And this is the deterioration of spraying and evaporation of fuel and increasing the duration of engine warm-up. At such low ambient temperatures, the effective operation of the car in a garage depends significantly on the method of its preparation (which should at a minimum cost of fuel and energy resources to ensure rapid and reliable engine start and accelerated warm-up). We decided to obtain thermal energy to heat the inlet air at no additional cost. This is the installation of a gasoline engine with a spark ignition of the incandescent coil in the intake air line, which will receive power from the battery. Such modernization of the system does not require major design changes and significant financial investments Unresolved issues remain to assess the effectiveness of the process of heating the air entering the combustion chamber of the engine to create a working mixture. It should be noted that the optimal heating of the engines is most appropriate to carry out (ie heating the coolant and oil in the engine lubrication system) not to the temperature of the operating thermal mode, but to the temperature that ensures its reliable start. Results. The scheme of connection of a heater of intake air in an onboard electric network of the car is presented. The results of the heat balance of the studied gasoline engine (using cold and heated air flow) during its heating are obtained. The optimum temperature of the warmed-up engine at which further economical operation of the car is possible is established. Originality. This spiral heater was first used to heat the intake air charge during the start-up and warm-up of a gasoline engine. Practical value. The developed heating equipment can be used for both gasoline and diesel internal combustion engines. It should be switched on only during engine start-up and warm-up.


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