scholarly journals Thermal Comfort Performances of Temporary Shelters Using Experimental and Computational Assessments

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 655
Author(s):  
Alex Yong Kwang Tan ◽  
Chi-Keong Tan
Keyword(s):  
Relative Humidity ◽  
Thermal Comfort ◽  
Ambient Temperature ◽  
Double Layers ◽  
Average Speed ◽  
Time Period ◽  
Standard Configuration ◽  
Air Speed ◽  
Better Than

This paper examines the thermal comfort of temporary shelters under Taiwan’s subtropical summer conditions. The temperature within the tent was higher compared to the standard configuration of the temporary shelter, but its relative humidity was lower. During the time period 09:30 to 14:30, temperatures at the center of the tent at positions 0.10 m, 1.10 m and 1.70 m above ground were 3.1 °C, 5.5 °C and 6.0 °C higher, respectively, than the average ambient temperature of 36.3 °C. However, temperatures for the standard configuration at similar central positions of 0.10 m, 1.10 m and 1.70 m above ground were 1.2 °C, 0.5 °C and 0.7 °C lower, respectively, than the same average ambient. In the afternoon, the standard configuration (PMV of 3.14 and PPD of 100) performed better than the tent (PMV of 5.03 and PPD of 100), although neither achieved thermal comfort. Various experimental configurations showed that double layers of roof lowered temperatures, but the thermal comfort (PMV of 3.32 and PPD of 100) remained unchanged. Various computational configurations showed that closing the door and one window and installing a mechanical fan of average speed 2.75 m/s lowered the temperature and increased the air speed to achieve thermal comfort with PMV and PPD values of 1.49 and 50, respectively.

scholarly journals Evaluation of Temperature-Based Empirical Models and Machine Learning Techniques to Estimate Daily Global Solar Radiation at Biratnagar Airport, Nepal

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Sandeep Dhakal ◽  
Yogesh Gautam ◽  
Aayush Bhattarai
Keyword(s):  
Machine Learning ◽  
Relative Humidity ◽  
Linear Regression ◽  
Solar Radiation ◽  
Ambient Temperature ◽  
Sunshine Duration ◽  
Global Solar Radiation ◽  
Empirical Models ◽  
Stepwise Linear Regression ◽  
Better Than

Global solar radiation (GSR) is a critical variable for designing photovoltaic cells, solar furnaces, solar collectors, and other passive solar applications. In Nepal, the high initial cost and subsequent maintenance cost required for the instrument to measure GSR have restricted its applicability all over the country. The current study compares six different temperature-based empirical models, artificial neural network (ANN), and other five different machine learning (ML) models for estimating daily GSR utilizing readily available meteorological data at Biratnagar Airport. Amongst the temperature-based models, the model developed by Fan et al. performs better than the rest with an R2 of 0.7498 and RMSE of 2.0162 MJm−2d−1. Feed-forward multilayer perceptron (MLP) is utilized to model daily GSR utilizing extraterrestrial solar radiation, sunshine duration, maximum and minimum ambient temperature, precipitation, and relative humidity as inputs. ANN3 performs better than other ANN models with an R2 of 0.8446 and RMSE of 1.4595 MJm−2d−1. Likewise, stepwise linear regression performs better than other ML models with an R2 of 0.8870 and RMSE of 1.5143 MJm−2d−1. Thus, the model developed by Fan et al. is recommended to estimate daily GSR in the region where only ambient temperature data are available. Similarly, a more robust ANN3 and stepwise linear regression models are recommended to estimate daily GSR in the region where data about sunshine duration, maximum and minimum ambient temperature, precipitation, and relative humidity are available.

scholarly journals Study of Human Thermal Comfort for Cyber–Physical Human Centric System in Smart Homes

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 372 ◽  
Author(s):  
Yuan Fang ◽  
Yuto Lim ◽  
Sian En Ooi ◽  
Chenmian Zhou ◽  
Yasuo Tan
Keyword(s):  
Heart Rate ◽  
Relative Humidity ◽  
Environmental Factors ◽  
Thermal Comfort ◽  
Smart Home ◽  
Comfort Level ◽  
Human Model ◽  
Human Thermal Comfort ◽  
Air Speed ◽  
Individual Human

An environmental thermal comfort model has previously been quantified based on the predicted mean vote (PMV) and the physical sensors parameters, such as temperature, relative humidity, and air speed in the indoor environment. However, first, the relationship between environmental factors and physiology parameters of the model is not well investigated in the smart home domain. Second, the model that is not mainly for an individual human model leads to the failure of the thermal comfort system to fulfill the human’s comfort preference. In this paper, a cyber–physical human centric system (CPHCS) framework is proposed to take advantage of individual human thermal comfort to improve the human’s thermal comfort level while optimizing the energy consumption at the same time. Besides that, the physiology parameter from the heart rate is well-studied, and its correlation with the environmental factors, i.e., PMV, air speed, temperature, and relative humidity are deeply investigated to reveal the human thermal comfort level of the existing energy efficient thermal comfort control (EETCC) system in the smart home environment. Experimental results reveal that there is a tight correlation between the environmental factors and the physiology parameter (i.e., heart rate) in the aspect of system operational and human perception. Furthermore, this paper also concludes that the current EETCC system is unable to provide the precise need for thermal comfort to the human’s preference.

CATFISH DRYING (Clarias Batraclus) USING ‘TEKO BERSAYAP’ SOLAR DRYER

2012 ◽  
Vol 2 (1) ◽  
pp. 14-20
Author(s):  
Yuwana Yuwana
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Ambient Temperature ◽  
Drying Rate ◽  
Drying Process ◽  
Drying Time ◽  
Ambient Relative Humidity ◽  
Solar Dryer

Experiment on catfish drying employing ‘Teko Bersayap’ solar dryer was conducted. The result of the experiment indicated that the dryer was able to increase ambient temperature up to 44% and decrease ambient relative humidity up to 103%. Fish drying process followed equations : KAu = 74,94 e-0,03t for unsplitted fish and KAb = 79,25 e-0,09t for splitted fish, where KAu = moisture content of unsplitted fish (%), KAb = moisture content of splitted fish (%), t = drying time. Drying of unsplitted fish finished in 43.995 hours while drying of split fish completed in 15.29 hours. Splitting the fish increased 2,877 times drying rate.

scholarly journals A novel mouse model of heatstroke accounting for ambient temperature and relative humidity

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Kazuyuki Miyamoto ◽  
Keisuke Suzuki ◽  
Hirokazu Ohtaki ◽  
Motoyasu Nakamura ◽  
Hiroki Yamaga ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Temperature ◽  
Relative Humidity ◽  
Ambient Temperature ◽  
Core Body Temperature ◽  
Heat Exposure ◽  
Organ Damage ◽  
Core Body ◽  
The Impact ◽  
Treatment Water

Abstract Background Heatstroke is associated with exposure to high ambient temperature (AT) and relative humidity (RH), and an increased risk of organ damage or death. Previously proposed animal models of heatstroke disregard the impact of RH. Therefore, we aimed to establish and validate an animal model of heatstroke considering RH. To validate our model, we also examined the effect of hydration and investigated gene expression of cotransporter proteins in the intestinal membranes after heat exposure. Methods Mildly dehydrated adult male C57/BL6J mice were subjected to three AT conditions (37 °C, 41 °C, or 43 °C) at RH > 99% and monitored with WetBulb globe temperature (WBGT) for 1 h. The survival rate, body weight, core body temperature, blood parameters, and histologically confirmed tissue damage were evaluated to establish a mouse heatstroke model. Then, the mice received no treatment, water, or oral rehydration solution (ORS) before and after heat exposure; subsequent organ damage was compared using our model. Thereafter, we investigated cotransporter protein gene expressions in the intestinal membranes of mice that received no treatment, water, or ORS. Results The survival rates of mice exposed to ATs of 37 °C, 41 °C, and 43 °C were 100%, 83.3%, and 0%, respectively. From this result, we excluded AT43. Mice in the AT 41 °C group appeared to be more dehydrated than those in the AT 37 °C group. WBGT in the AT 41 °C group was > 44 °C; core body temperature in this group reached 41.3 ± 0.08 °C during heat exposure and decreased to 34.0 ± 0.18 °C, returning to baseline after 8 h which showed a biphasic thermal dysregulation response. The AT 41 °C group presented with greater hepatic, renal, and musculoskeletal damage than did the other groups. The impact of ORS on recovery was greater than that of water or no treatment. The administration of ORS with heat exposure increased cotransporter gene expression in the intestines and reduced heatstroke-related damage. Conclusions We developed a novel mouse heatstroke model that considered AT and RH. We found that ORS administration improved inadequate circulation and reduced tissue injury by increasing cotransporter gene expression in the intestines.

scholarly journals Validation of SCIAMACHY limb NO<sub>2</sub> profiles using solar occultation measurements

2011 ◽  
Vol 4 (4) ◽  
pp. 4753-4800
Author(s):  
R. Bauer ◽  
A. Rozanov ◽  
C. A. McLinden ◽  
L. L. Gordley ◽  
W. Lotz ◽  
...  
Keyword(s):  
The Past ◽  
Middle Latitudes ◽  
Solar Occultation ◽  
Time Period ◽  
Vertical Distributions ◽  
Global Coverage ◽  
Scanning Imaging ◽  
Diurnal Effect ◽  
Better Than ◽  
Balloon Measurements

Abstract. The increasing amounts of reactive nitrogen in the stratosphere necessitates accurate global measurements of stratospheric nitrogen dioxide (NO2). Over the past decade, the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) instrument on ENVISAT (European Environmental Satellite) has been providing global coverage of stratospheric NO2 every 6 days, which is otherwise difficult to achieve with other systems (e.g. balloon measurements, solar occultation). In this study, the vertical distributions of NO2 retrieved from limb measurements of the scattered solar light from the SCIAMACHY instrument are validated using NO2 products from three different satellite instruments (SAGE II, HALOE and ACE-FTS). The retrieval approach, as well as the sensitivity of the SCIAMACHY NO2 limb data product are discussed, and the photochemical corrections needed to make this validation feasible, as well as the chosen collocation criteria are described. For each instrument, a time period of two years is analyzed with several hundreds of collocation pairs for each year and instrument. The agreement between SCIAMACHY and each instrument is found to be better than 10 % between 22–24 km and 40 km. Additionally, NO2 amounts in three different latitude regions are validated individually, with considerably better agreements in high and middle latitudes compared to tropics. Differences with SAGE II and ACE-FTS below 20 km are consistent with those expected from the diurnal effect.

Design Range of Indoor Relative Humidity in Radiant Cooling Environment

2011 ◽  
Vol 243-249 ◽  
pp. 4905-4908
Author(s):  
Xue Min Sui ◽  
Xu Zhang ◽  
Guang Hui Han
Keyword(s):  
Relative Humidity ◽  
Thermal Comfort ◽  
Mean Radiant Temperature ◽  
Design Standards ◽  
Human Thermal Comfort ◽  
Radiant Cooling ◽  
Climate Parameter ◽  
Radiant Temperature ◽  
Thermal Comfort Model ◽  
The Impact

Relative humidity is an important micro-climate parameter in radiant cooling environment. Based on the human thermal comfort model, this paper studied the effect on PMV index of relative humidity, and studied the relationship of low mean radiant temperature and relative humidity, drew the appropriate design range of indoor relative humidity for radiant cooling systems.The results show that high relative humidity can compensate for the impact on thermal comfort of low mean radiant temperature, on the premise of achieving the same thermal comfort requirements. However, because of the limited compensation range of relative humidity, together with the constraints for it due to anti-condensation of radiant terminal devices, the design range of relative humidity should not be improved, and it can still use the traditional air-conditioning design standards.

International Real Estate Review

2017 ◽  
Vol 20 (1) ◽  
pp. 1-21
Author(s):  
Greg MacKinnon ◽  
◽  
Jon Spinney ◽  
Keyword(s):  
Real Estate ◽  
Equity Market ◽  
Portfolio Performance ◽  
Real Estate Investment ◽  
Construction Techniques ◽  
Time Period ◽  
High Volatility ◽  
Weighted Portfolio ◽  
Portfolio Design ◽  
Better Than

We examine the market for U.S. equity real estate investment trusts (REITs) for evidence of the volatility effect, in which low volatility stocks tend to outperform high volatility ones, as has been found in the general equity market by prior research. While there is some evidence of a volatility effect in the first ten years of the sample, this disappears in a more recent time period. Furthermore, we test the efficacy of low risk portfolio construction techniques and find that none perform any better than a market cap weighted portfolio ¡V although they are also no worse ¡V over any of the time periods examined. Thus, there is no evidence that using a risk-based portfolio design that emphasizes low volatility would improve portfolio performance for a REIT allocation.

Heat balance, haematology and serum chemistry of layers under varying stocking density reared in locally fabricated metal-type cage system

2020 ◽  
Vol 40 (2) ◽  
pp. 92-103
Author(s):  
K. O. Bello ◽  
A. E. Adiatu ◽  
M. O. Osunlakin ◽  
O. O. Oni
Keyword(s):  
Relative Humidity ◽  
Ambient Temperature ◽  
Rectal Temperature ◽  
Heat Balance ◽  
Total Protein ◽  
Stocking Density ◽  
Fabricated Metal ◽  
Cage System ◽  
Chemical Measurements ◽  
Metal Type

One hundred and thirty five 18weeks old Bovans Nera Black strain pullets were used in a 10week study to determine their heat balance and blood profile under varying stocking density in locally fabricated metal-type cage system. The cages were stocked 2, 3 and 4birds/cell. Daily ambient temperature and relative humidity of the cage and rectal temperature of the birds were taken and heat balance calculated. Record of Packed cell volume (PCV), Haemoglobin concentration (Hb), Red blood cell (RBC), White blood count (WBC) and differential of the birds were taken at beginning and end of the study for the haematological indices while blood glucose, total protein, Albumin and blood urea were taken for the bio-chemical measurements. Ambient temperature, relative humidity, and heat balance showed no significant (P>0.05) difference with cage stocking density. Cage stocking density had significant (P<0.05) effect on rectal temperature of layers. Bird stocked 3/cell recorded the least (41.14oC) rectal temperature while those stocked 4/cell recorded the highest (41.27oC). All the haematological parameters of the birds were not significantly (P>0.05) influenced by stocking density of the cage type. Bio-chemical measurements were not significantly (P>0.05) different among layers under varying stocking density of the cage except total protein (P<0.05). Layers stocked 4/cell recorded highest (5.22g/dl) total protein while those stocked 3/cell had the least value (4.37g/dl). However, the values were within the normal range recommended for healthy chicken. The study concluded that locally fabricated metal-type battery cage could be used to rear layers and stocking density of 3birds/cell is ideal without compromising the welfare of the birds.

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