scholarly journals Effects of increasing air temperature on physiological and productive responses of dairy cows at different relative humidity and air velocity levels

2021 ◽  
Author(s):  
M. Zhou ◽  
A.J.A. Aarnink ◽  
T.T.T. Huynh ◽  
I.D.E. van Dixhoorn ◽  
P.W.G. Groot Koerkamp
Keyword(s):  
Relative Humidity ◽  
Dairy Cows ◽  
Air Temperature ◽  
Air Velocity

Thermal Lethality of Salmonella in Chicken Leg Quarters Processed via an Air/Steam Impingement Oven

2004 ◽  
Vol 67 (3) ◽  
pp. 493-498 ◽  
Author(s):  
R. Y. MURPHY ◽  
K. H. DRISCOLL ◽  
L. K. DUNCAN ◽  
T. OSAILI ◽  
J. A. MARCY
Keyword(s):  
Relative Humidity ◽  
Surface Area ◽  
Air Temperature ◽  
Cooking Time ◽  
Air Velocity ◽  
Poultry Products ◽  
Product Surface ◽  
Cooking Times

Chicken leg quarters were injected with 0.1 ml of the cocktail culture per cm2 of the product surface area to contain about 7 log(CFU/g) of Salmonella. The inoculated leg quarters were processed in an air/steam impingement oven at an air temperature of 232°C, an air velocity of 1.4 m/s, and a relative humidity of 43%. The endpoint product temperatures were correlated with the cooking times. A model was developed for pathogen thermal lethality up to 7 log(CFU/g) reductions of Salmonella in correlation to the product mass (140 to 540 g) and cooking time (5 to 35 min). The results from this study are useful for validating thermal lethality of pathogens in poultry products that are cooked via impingement ovens.

scholarly journals A Study on Suitable Habitat for Swiftlet Farming

2009 ◽  
Vol 1 (1) ◽  
pp. 1-7
Author(s):  
Ibrahim S. H. ◽  
Teo W.C. ◽  
Baharun A.
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Air Temperature ◽  
Capital Investment ◽  
Suitable Habitat ◽  
Key Factors ◽  
Air Velocity ◽  
Animal Products ◽  
New Industry ◽  
Temperature Surface

Swiftlet farming is a new industry in Sarawak as compared to other long-standing industries such as rubber, palm oil and timber. It is one of the businesses that involved a small capital investment that could generate enormous returns in the future. Swiftlet farming involves the conversion of human-centric building into structures for Swiftlet. The purpose of this conversion is to let Swiftlet for nesting and protect them. The design and construction of such building will also helps to accommodate Swiftlets' population. The nest of the Edible-nest Swiftlet rank amongst the world's most expensive animal products. Therefore, in order to increase the productivity of bird nest, study of the suitable habitat for Swiftlet should be done thoroughly. Environmental factors such as air temperature, surface temperature, relative humidity, air velocity and light intensity are the key factors for a successful Swiftlet farm house. Internal air temperature of building should be maintained from 26°C to 35°C, relative humidity from 80% to 90%, low air velocity and light intensity less than 5 LUX. Proper ventilation and installation of a humidifier could help the building to achieve the desirable range of environment factors. Location of structure will also be considered from direct sunlight direction to reduce the internal temperature. Only licensed Swiftlet farming is legal.

Drying of Heavily Salted Fish

1945 ◽  
Vol 6d (5) ◽  
pp. 380-391 ◽  
Author(s):  
E. P. Linton ◽  
A. L. Wood
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Skin Surface ◽  
Medium Size ◽  
Air Velocity ◽  
Salted Fish

The experimental drying of cut samples and of whole salt fish under various air conditions shows that the optimum air velocity is 100 to 125 cm. per second, air temperature 26 °C, and relative humidity 45 to 55 per cent. High drying potentials inhibit drying owing to the formation of an impervious salt-protein crust on the surface of the fish.The skin surface of the fish dries about 50 to 75 per cent as fast as the split surface. Under the recommended air conditions medium size salt codfish are dried from 130 per cent to 75 per cent, dry basis, moisture in about 40 hours.

Effects of Dry Chilling on the Microflora on Beef Carcasses at a Canadian Beef Packing Plant

2016 ◽  
Vol 79 (4) ◽  
pp. 538-543 ◽  
Author(s):  
Y. LIU ◽  
M. K. YOUSSEF ◽  
X. YANG
Keyword(s):  
Escherichia Coli ◽  
Relative Humidity ◽  
Air Temperature ◽  
Ambient Air ◽  
Indicator Organisms ◽  
Air Velocity ◽  
E Coli ◽  
Beef Carcasses ◽  
Significant Difference

ABSTRACT The aim of this study was to determine the course of effects on the microflora on beef carcasses of a commercial dry chilling process in which carcasses were dry chilled for 3 days. Groups of 25 carcasses selected at random were sampled when the chilling process commenced and after the carcasses were chilled for 1, 2, 4, 6, 8, 24, and 67 h for determination of the numbers of aerobes, coliforms, and Escherichia coli. The temperatures of the surfaces and the thickest part of the hip (deep leg) of carcasses, as well as the ambient air conditions, including air temperature, velocity, and relative humidity (RH), were monitored throughout the chilling process. The chiller was operated at 0°C with an off-coil RH of 88%. The air velocity was 1.65 m/s when the chiller was loaded. The initial RH levels of the air in the vicinity of carcasses varied with the locations of carcasses in the chiller and decreased rapidly during the first hour of chilling. The average times for shoulder surfaces, rump surfaces, and the deep leg of carcasses to reach 7°C were 13.6 ± 3.1, 16.0 ± 2.4 and 32.4 ± 3.2 h, respectively. The numbers of aerobes, coliforms, and E. coli on carcasses before chilling were 5.33 ± 0.42, 1.95 ± 0.77, 1.42 ± 0.78 log CFU/4,000 cm2, respectively. The number of aerobes on carcasses was reduced by 1 log unit each in the first hour of chilling and in the subsequent 23 h of chilling. There was no significant difference (P > 0.05) between the numbers of aerobes recovered from carcasses after 24 and 67 h of chilling. The total numbers (log CFU/100,000 cm2) on carcasses before chilling and after the first hour of chilling were 3.86 and 2.24 for coliforms and 3.30 and 2.04 for E. coli. The subsequent 23 h of chilling reduced the numbers of both groups of organisms by a further log unit. No coliforms or E. coli were recovered after 67 h of chilling. The findings show that the chilling regime investigated in this study resulted in significant reductions of all three groups of indicator organisms.

scholarly journals Modeling of Heat Stress in Sows—Part 1: Establishment of the Prediction Model for the Equivalent Temperature Index of the Sows

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1472
Author(s):  
Mengbing Cao ◽  
Chao Zong ◽  
Xiaoshuai Wang ◽  
Guanghui Teng ◽  
Yanrong Zhuang ◽  
...  
Keyword(s):  
Heat Stress ◽  
Relative Humidity ◽  
Skin Temperature ◽  
Air Temperature ◽  
Physiological Response ◽  
Equivalent Temperature ◽  
Air Velocity ◽  
Thermal Indices ◽  
Thermal Index ◽  
Temperature Index

Heat stress affects the estrus time and conception rate of sows. Compared with other life stages of pigs, sows are more susceptible to heat stress because of their increased heat production. Various indicators can be found in the literature assessing the level of heat stress in pigs. However, none of them is specific to assess the sows’ thermal condition. Moreover, thermal indices are mainly developed by considering partial environment parameters, and there is no interaction between the index and the animal’s physiological response. Therefore, this study aims to develop a thermal index specified for sows, called equivalent temperature index for sows (ETIS), which includes parameters of air temperature, relative humidity and air velocity. Based on the heat transfer characteristics of sows, multiple regression analysis is used to combine air temperature, relative humidity and air velocity. Environmental data are used as independent variables, and physiological parameters are used as dependent variables. In 1029 sets of data, 70% of the data is used as the training set, and 30% of the data is used as the test set to create and develop a new thermal index. According to the correlation equation between ETIS and temperature-humidity index (THI), combined with the threshold of THI, ETIS was divided into thresholds. The results show that the ETIS heat stress threshold is classified as follows: suitable temperature ETIS < 33.1 °C, mild temperature 33.1 °C ≤ ETIS < 34.5 °C, moderate stress temperature 34.5 °C ≤ ETIS < 35.9 °C, and severe temperature ETIS ≥ 35.9 °C. The ETIS model can predict the sows’ physiological response in a good manner. The correlation coefficients R of skin temperature was 0.82. Compared to early developed thermal indices, ETIS has the best predictive effect on skin temperature. This index could be a useful tool for assessing the thermal environment to ensure thermal comfort for sows.

Modeling of Basil Leaves Drying by GA–ANN

2013 ◽  
Vol 9 (4) ◽  
pp. 393-401 ◽  
Author(s):  
Amin Taheri-Garavand ◽  
Shahin Rafiee ◽  
Alireza Keyhani ◽  
Payam Javadikia
Keyword(s):  
Neural Network ◽  
Genetic Algorithm ◽  
Relative Humidity ◽  
Moisture Content ◽  
Air Temperature ◽  
High Accuracy ◽  
Air Velocity ◽  
Feed Forward Neural Network ◽  
Air Temperatures ◽  
Hidden Layer

AbstractIn this research, the experiment is done by a dryer. It could provide any desired drying air temperature between 20 and 120°C and air relative humidity between 5 and 95% and air velocity between 0.1 and 5.0 m/s with high accuracy, and the drying experiment was conducted at five air temperatures of 40, 50, 60, 70 and 80°C and at three relative humidity 20, 40 and 60% and air velocity of 1.5, 2 and 2.5 m/s to dry Basil leaves. Then with developed Program in MATLAB software and by Genetic Algorithm could find the best Feed-Forward Neural Network (FFNN) structure to model the moisture content of dried Basil in each condition; anyway the result of best network by GA had only one hidden layer with 11 neurons. This network could predict moisture content of dried basil leaves with correlation coefficient of 0.99.

The Globe Thermometer Response under Varying Thermal Components

1987 ◽  
Vol 31 (12) ◽  
pp. 1341-1344
Author(s):  
C.H. Lee ◽  
J.D. Ramsey
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Radiant Heat ◽  
Air Velocity ◽  
Environmental Chamber

This study investigates the effect of air velocity and other thermal components on the globe thermometer response. An experiment was conducted in an environmental chamber in order to measure globe temperatures under varying air velocity, relative humidity and air temperature. This study was performed under three different radiant heat levels. It was found that air velocity has a significant effect on the globe thermometer response. This effect is quantified in this study. Neither air temperature nor relative humidity was found to have a significant effect on globe thermometer response.

The Study of Thermal Comfort and Noise Level in Battery Plate Factory

2014 ◽  
Vol 663 ◽  
pp. 474-479
Author(s):  
Mohd Anas Mohd Sabri ◽  
Mohd Faizal Mat Tahir ◽  
Kamaruzaman Sopian ◽  
Muhammad Hadi Zabidi Rosdi
Keyword(s):  
Relative Humidity ◽  
Metabolic Rate ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Noise Level ◽  
Comfort Level ◽  
The Other ◽  
Air Velocity ◽  
Other Hand ◽  
Radiant Temperature

The successful of manufacturing factories in industry is highly dependent on a productivity of their employees especially operators. It was identified that comfort and noise level can reduce the productivity of their workers. This study is to determine the level of thermal and noise comfort in the battery plate factory. This study was conducted in three days and location of the study is at battery plate factory in Semenyih, Selangor, Malaysia. The scope of study is focused at plate manufacturing area where the employee estimated 40 persons. The thermal comfort level can be determined by calculating PMV and PPD. This study involved six factors of comfort which is air temperature, average radiant temperature, air velocity, relative humidity, metabolic rate and clothes insulation. Then the study of noise level was conducted by determining LAeq, T, Lmax and Lmin. To carry out this study, Babuc-A equipment were used. The analysis show the area of the manufacturing battery plate having a discomfort condition and PMV result is between 1.5 until 3. Air temperature on the other hand is between 27.4°C-37.8°C while relative humidity is between range 35.35% -92.1% and air velocity 0 m/s-1.28 m/s. Meanwhile the LAeq,T value in the factory is varied from 68 to 80 dB.

scholarly journals Spatio-Thermal Variability and Behaviour as Bio-Thermal Indicators of Heat Stress in Dairy Cows in a Compost Barn: A Case Study

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1197
Author(s):  
Frederico Márcio Corrêa Vieira ◽  
Allessandro Augusto Soares ◽  
Piotr Herbut ◽  
Edgar de Souza Vismara ◽  
Dorota Godyń ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Spatial Variability ◽  
Dairy Cows ◽  
Air Temperature ◽  
Thermal Environment ◽  
The North ◽  
Bed Temperature ◽  
Water Trough ◽  
Thermal Indicators ◽  
Behavioural Aspects

The spatial variability and behavioural aspects of compost-bedded pack barns remain unknown in subtropical regions. In this study, we investigated whether spatial variability occurs in the thermal environment of a compost barn and how the behaviour of dairy cows with different numbers of lactations differs in this system. The spatial sampling design comprised a grid of 108 locations inside the facility. At each location, we measured air temperature, relative humidity, wind speed, and bed temperature at 9:00, 12:00, and 15:00. We performed 24-h behavioural observations. Regarding spatial variability, the north face showed high air temperature values, and the distribution of relative humidity varied from the north to the south face. Kriging maps revealed a high bedding temperature trend, indicating heterogeneous ventilation management. Primiparous cows visited the water trough during the hottest hours of the day, whereas multiparous cows displayed a higher probability of walking during these periods. In conclusion, we observed a heterogeneous management of ventilation through the spatial distribution of the thermal environment inside the compost-bedded pack barn, with multiparous cows exhibiting dominance over primiparous cows seeking environmental resources.

scholarly journals Impact of the measurement uncertainty on the monitoring of thermal comfort through AI predictive algorithms

ACTA IMEKO ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 221
Author(s):  
Nicole Morresi ◽  
Sara Casaccia ◽  
Marco Arnesano ◽  
Gian Marco Revel
Keyword(s):  
Neural Network ◽  
Artificial Intelligence ◽  
Relative Humidity ◽  
Measurement Uncertainty ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Air Velocity ◽  
Human Thermal Comfort ◽  
Innovative Method ◽  
Predictive Algorithms

This paper presents an approach to assess the measurement uncertainty of human thermal comfort by using an innovative method that comprises a heterogeneous set of data, made by physiological and environmental quantities, and artificial intelligence algorithms, using Monte Carlo method (MCM). The dataset is made up of heart rate variability (HRV) features, air temperature, air velocity and relative humidity. Firstly, MCM is applied to compute the measurement uncertainty of the HRV features: results have shown that among 13 participants, there are uncertainty values in the measurement of HRV features that ranges from ±0.01% to ±0.7 %, suggesting that the uncertainty can be generalized among different subjects. Secondly, MCM is applied by perturbing the input parameters of random forest (RF) and convolutional neural network (CNN) algorithm, trained to measure human thermal comfort. Results show that environmental quantities produce different uncertainty on the thermal comfort: RF has the highest uncertainty due to the air temperature (14 %), while CNN has the highest uncertainty when relative humidity is perturbed (10.5 %). A sensitivity analysis also shows that air velocity is the parameter that causes a higher deviation of thermal comfort

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