Thermo-physiological comfort of business clothing incorporating phase change materials in a cold environment

2018 ◽  
Vol 30 (1) ◽  
pp. 49-61 ◽  
Author(s):  
Damjana Celcar
Keyword(s):  
Skin Temperature ◽  
Environmental Conditions ◽  
Phase Change Materials ◽  
Physiological Parameters ◽  
Cold Environment ◽  
Mean Skin Temperature ◽  
Content Type ◽  
Business Clothing ◽  
Study Participants ◽  
Environmental Temperatures

Purpose The purpose of this paper is to investigate the thermo-physiological comfort of male business garments made of common textiles, as well as business clothing that contains phase change materials (PCMs) as a lining or outerwear material. In view of the fact that people wear business clothing throughout the whole day in different environmental conditions, this study investigate the effect of PCMs incorporated in male business clothing systems on the thermo-physiological comfort of the wearer under different cold environmental conditions. Design/methodology/approach The influence of particular business garments on the thermo-physiological comfort of the wearer during different physical activities and cold environmental temperatures was determined experimentally with the help of study participants, as a change of two physiological parameters: mean skin temperature and heart rate. A questionnaire and an assessment scale were also used in order to evaluate the wearer’s subjective feeling of comfort. In this investigation, all tests with study participants were performed under artificially created environmental conditions in a climate chamber at different cold environmental temperatures ranging from 10°C to −5°C with increments of 5°C, and different physical activities that simulate as closely as possible real life activities such as sitting and walking. Findings The results of the performed research work show that PCMs provide a small temporary thermal effect that is reflected in small increases or decreases in mean skin temperature during changes in activity. Furthermore, it was concluded that the small effect of PCMs in business clothing systems on the thermo-physiological comfort of the wearer in a cold environment, which is shown as a change of mean skin temperature when subjects walk on a treadmill and subsequently move to a sitting position, should not be ignored in a cold environment where low skin temperatures were measured. Practical implications The results of this study demonstrate that the physiological parameters of thermo-physiological comfort, in combination with subjective evaluation, provide valuable information for textile and clothing manufactures as well as scientists and engineers involved in the design and development of new products with thermal comfort as a quality criterion. Originality/value The investigation shows that different environmental conditions, activity levels and thermal properties of clothing systems have a considerable impact on the physiological parameters of the subjects and subjective assessment of thermal comfort in a cold environment, and that PCMs incorporated in business clothing systems provide a small temporary thermal effect that is reflected in small increases or decreases in mean skin temperature during changes in activity, such as when subjects walk on a treadmill and subsequently move to a sitting position.

Thermoregulation properties of composite phase change materials in high temperature environmental conditions

2018 ◽  
Vol 30 (4) ◽  
pp. 507-516 ◽  
Author(s):  
Kai Yang ◽  
Mingli Jiao ◽  
Sifan Wang ◽  
Yuanyuan Yu ◽  
Quan Diao ◽  
...  
Keyword(s):  
High Temperature ◽  
Phase Change ◽  
Skin Temperature ◽  
Human Body ◽  
Environmental Conditions ◽  
Phase Change Materials ◽  
Content Type ◽  
Temperature Conditions ◽  
Composite Phase Change Materials ◽  
C 50

Purpose The purpose of this paper is to investigate thermoregulation properties of different composite phase change materials (PCMs), which could be used in the high temperature environmental conditions to protect human body against the extra heat flow. Design/methodology/approach Three kinds of composite PCM samples were prepared using the selected pure PCMs, including n-hexadecane, n-octadecane and n-eicosane. The DSC experiment was performed to get the samples’ phase change temperature range and enthalpy. The simulated high temperature experiments were performed using human arms in three different high temperature conditions (40°C, 45°C, 50°C), and the skin temperature variation curves varying with time were obtained. Then a comprehensive index TGP was introduced from the curves and calculated to evaluate the thermoregulation properties of different composite PCM samples comprehensively. Findings Results show that the composite PCM samples could provide much help to the high temperature human body. It could decrease the skin temperature quickly in a short time and it will not cause the over-cooling phenomenon. Comparing with other two composite PCM samples, the thermoregulation properties of the n-hexadecane and n-eicosane composite PCM is the best. Originality/value Using the n-hexadecane and n-eicosane composite PCM may provide people with better protection against the high temperature conditions, which is significative for the manufacture of functional thermoregulating textiles, garments or equipments.

scholarly journals Influence of Phase-Change Materials on Thermo-Physiological Comfort in Warm Environment

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Damjana Celcar
Keyword(s):  
Phase Change ◽  
Skin Temperature ◽  
Phase Change Materials ◽  
Research Work ◽  
Subjective Feeling ◽  
Mean Skin Temperature ◽  
Climate Chamber ◽  
Warm Environment ◽  
Business Clothing ◽  
The Impact

The purpose of this research work is to investigate the influence of phase-change materials (PCMs) on thermo-physiological comfort of different male business clothing systems evaluated in warm environment. The impact of particular business clothing on the thermo-physiological comfort of the wearer during different physical activity and environmental conditions (between 25°C and 10°C with step of 5°C), artificially created in a climate chamber, was determined experimentally, as a change of three physiological parameters of a human being: mean skin temperature, heart rate, and the amount of evaporated and condensed sweat. A questionnaire and an assessment scale were also used before, during, and after each experiment in order to evaluate the wearer’s subjective feeling of comfort. The results of the performed research work show that male business clothing systems in combination with PCMs do not affect the thermal-physiological comfort of the wearer in warm environment significantly, except at an ambient temperature of 15°C, where clothing systems in combination with PCMs produce a small heating effect. Furthermore, it was concluded that clothing systems in combination with PCMs indicate a small temporary thermal effect that is reflected in a slight rising or lowering of mean skin temperature during activity changes.

scholarly journals A SUBJECTIVE EVALUATION OF THE THERMAL COMFORT OF CLOTHING EVALUATED IN COLD ENVIRONMENT

2014 ◽  
Vol 5 (10) ◽  
Author(s):  
Damjana Celcar
Keyword(s):  
Thermal Comfort ◽  
Ambient Temperature ◽  
Environmental Conditions ◽  
Phase Change Materials ◽  
Thermal State ◽  
Subjective Evaluation ◽  
Real Life ◽  
Subjective Feeling ◽  
Business Clothing ◽  
The Impact

In this study, the thermal comfort of clothing was subjectively evaluated in cold environmental conditions. Different male business clothing systems, made of standard textiles (wool and wool-mixture), and materials that contain phase-change materials (PCMs), were developed. The research was performed with the help of test subjects in a computer controlled climatic chamber, in artificially created cold environmental conditions, at ambient temperatures of 10 °C, 5 °C and 0 °C, and with physical activity that is as reminiscent as possible of the real life situation of wearing clothes, such as sitting and walking on a treadmill. The impact of particular business clothing systems and varied cold environmental conditions on the wearer’s subjective feeling of thermal comfort was determined with a questionnaire and an assessment scale of thermal comfort defined by standard ISO 10551:2004. For this purpose, an analysis of the subjective evaluation of thermal comfort, the desired thermal state, the acceptability of the current situation and their personal tolerance of the environment, was made before, during and after each experiment. The results of the research show that subjective evaluations of thermal comfort directly depend on environmental conditions, as well as clothing systems. From this subjective evaluation it can be seen that in spite of lower mean skin temperatures the test subjects felt comfortable at an ambient temperature of 10 °C. It is also evident that the analysed clothing systems are not suitable for wearing below an ambient temperature of 0 °C, because the test subjects felt uncomfortable.

Day–night variation of thermoregulatory responses of heifers exposed to high environmental temperatures

1997 ◽  
Vol 129 (2) ◽  
pp. 199-204 ◽  
Author(s):  
C. M. MUNDIA ◽  
S. YAMAMOTO
Keyword(s):  
Skin Temperature ◽  
Respiration Rate ◽  
Heat Balance ◽  
Thermal Sensitivity ◽  
Skin Surface ◽  
Mean Skin Temperature ◽  
Mean Body Temperature ◽  
Rate Of Increase ◽  
Vaginal Temperature ◽  
Environmental Temperatures

In order to assess relative thermal sensitivity between the day and the night, vaginal temperature (Tv), heat production (HP), heart rate (HR), respiration rate (RR), skin surface temperatures (from which mean skin temperature (Ts) was calculated) and standing time were measured at environmental temperatures (Te) of 23, 28, 33 and 38°C during the day (11.00–15.00 h) and during the night (23.00–03.00 h) using four Holstein heifers. Both Tv and mean body temperature (Tb) were greater during the night than during the day, increased with increased Te, and the rate of increase of both Tv and Tb with increased Te was greater during the night (P<0·05). Estimated mean HP was similar during the night and during the day, and HP did not increase with increased Te. Respiration rate was greater but not significantly different at night compared to during the day, and increased with increased Te. Mean skin temperature was similar between day and night, and increased with increased Te. The amount of time engaged in standing activity was greater but not significantly different during the night than during the day and standing activity increased with increased Te. The results suggest that thermal sensitivity is lower during the night than during the day, and consequently the greater night responses of Tv and Tb, over day responses, are a requirement for the maintenance of heat balance.

INCREASING MEAN SKIN TEMPERATURE LINEARLY REDUCES THE VASOCONSTRICTION AND SHIVERING THRESHOLDS IN HUMANS

1994 ◽  
Vol 81 (SUPPLEMENT) ◽  
pp. A252
Author(s):  
C. Cheng ◽  
T. Matsukawa ◽  
A. Kurz ◽  
D. I. Sessler ◽  
B. Merrifield
Keyword(s):  
Skin Temperature ◽  
Mean Skin Temperature

Associated change in plantar temperature and sweating after transthoracic endoscopic T2–3 sympathectomy for palmar hyperhidrosis

2001 ◽  
Vol 95 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Han-Jung Chen ◽  
Cheng-Loong Liang ◽  
Kang Lu
Keyword(s):  
Skin Temperature ◽  
Temperature Change ◽  
The Body ◽  
Palmar Hyperhidrosis ◽  
Compensatory Sweating ◽  
Content Type ◽  
Postoperative Changes ◽  
The Face ◽  
The Difference ◽  
Fine Print

Object. Transthoracic endoscopic T2–3 sympathectomy is currently the treatment of choice for palmar hyperhidrosis. Compensatory sweating of the face, trunk, thigh, and sole of the foot was found in more than 50% of patients who underwent this procedure. The authors conducted this study to investigate the associated intraoperative changes in plantar skin temperature and postoperative plantar sweating. Methods. One hundred patients with palmar hyperhidrosis underwent bilateral transthoracic endoscopic T2–3 sympathectomy. There were 60 female and 40 male patients who ranged in age from 13 to 40 years (mean age 21.6 years). Characteristics studied included changes in palmar and plantar skin temperature measured intraoperatively, as well as pre- and postoperative changes in plantar sweating and sympathetic skin responses (SSRs). In 59 patients (59%) elevation of plantar temperature was demonstrated at the end of the surgical procedure. In this group, plantar sweating was found to be exacerbated in three patients (5%); plantar sweating was improved in 52 patients (88.1%); and no change was demonstrated in four patients (6.8%). In the other group of patients in whom no temperature change occurred, increased plantar sweating was demonstrated in three patients (7.3%); plantar sweating was improved in 20 patients (48.8%); and no change was shown in 18 patients (43.9%). The difference between temperature and sweating change was significant (p = 0.001). Compared with the presympathectomy rate, the rate of absent SSR also significantly increased after sympathectomy: from 20 to 76% after electrical stimulation and 36 to 64% after deep inspiration stimulation, respectively (p < 0.05). Conclusions. In contrast to compensatory sweating in other parts of the body after T2–3 sympathetomy, improvement in plantar sweating was shown in 72% and worsened symptoms in 6% of patients. The intraoperative plantar skin temperature change and perioperative SSR demonstrated a correlation between these changes.

Thermoregulatory responses during competitive marathon running

1977 ◽  
Vol 42 (6) ◽  
pp. 909-914 ◽  
Author(s):  
M. B. Maron ◽  
J. A. Wagner ◽  
S. M. Horvath
Keyword(s):  
Skin Temperature ◽  
Marathon Running ◽  
Heat Illness ◽  
Mean Skin Temperature ◽  
Total Water ◽  
Water Losses ◽  
Thermoregulatory Responses ◽  
Marked Disparity ◽  
Skin Temperatures ◽  
Cool Conditions

To assess thermoregulatory responses occuring under actual marathon racing conditions, rectal (Tre) and five skin temperatures were measured in two runners approximately every 9 min of a competitive marathon run under cool conditions. Race times and total water losses were: runner 1 = 162.7 min, 3.02 kg; runner 2 = 164.6 min, 2.43 kg. Mean skin temperature was similar throughout the race in the two runners, although they exhibited a marked disparity in temperature at individual skin sites. Tre plateaued after 35--45 min (runner 1 = 40.0--40.1, runner 2 = 38.9--39.2 degrees C). While runner 2 maintained a relatively constant level for the remainder of the race, runner 1 exhibited a secondary increase in Tre. Between 113 and 119 min there was a precipitous rise in Tre from 40.9 to 41.9 degrees C. Partitional calorimetric calculations suggested that a decrease in sweating was responsible for this increment. However, runner 1's ability to maintain his high Tre and running pace for the remaining 44 min of the race and exhibit no signs of heat illness indicated thermoregulation was intact.

The effect of clam shell powder on kinetics of water absorption of jute epoxy composite

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hemalata Jena ◽  
Abinash Panigrahi
Keyword(s):  
Water Absorption ◽  
Environmental Conditions ◽  
Epoxy Composite ◽  
Jute Fibre ◽  
Content Type ◽  
Clam Shell ◽  
New Class ◽  
Kinetics Of ◽  
Shell Powder ◽  
Marine Waste

Purpose Here, attempts have been made to explore the possible use of Marine waste as filler materials into the bio-fibre composites. Clam shell is a type of marine waste which belongs to the class of Bivalvia. It is mainly made of aragonite crystalline polymorphs. This paper aims to develop a new class of natural fibre composite in which jute fibre as reinforcement, epoxy as matrix and clam shell, as particulate microsphere filler. The study investigates the effects of different amounts of clam shell powder on the kinetics of water absorption of jute fibre-reinforced epoxy composite. Two different environmental conditions at room temperature, i.e. distilled water and seawater, are collected for this purpose. Moisture absorption reduces when clam shell is added to the jute-epoxy composite. The curve of water absorption of jute-epoxy composites with filler loading at both environmental conditions follows as Fickian behaviour. Design/methodology/approach Hand lay-up technique to fabricate the composite – Experimental observation Findings The incorporation of Clam shell filler in jute epoxy composite modified the water absorption property of the composite. Hence the present marine waste is an potential filler in jute fibre reinforced polymer composite. Originality/value The paper demonstrates a new class hybrid composite material which uses a marine waste as important phase in the bio-fibre-reinforced composite. It is a new work submitted for original research paper.

The human factor: assessing individuals’ perceptions related to cybersecurity

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Susan Ramlo ◽  
John B. Nicholas
Keyword(s):  
Computer Security ◽  
Quantitative Research ◽  
Q Methodology ◽  
Educational Interventions ◽  
Public And Private ◽  
College Majors ◽  
Content Type ◽  
Quantitative Research Methods ◽  
Security Breaches ◽  
Study Participants

Purpose The purpose of this paper is to reveal and describe the divergent viewpoints about cybersecurity within a purposefully selected group of people with a range of expertise in relation to computer security. Design/methodology/approach Q methodology [Q] uses empirical evidence to differentiate subjective views and, therefore, behaviors in relation to any topic. Q uses the strengths of qualitative and quantitative research methods to reveal and describe the multiple, divergent viewpoints that exist within a group where individuals sort statements into a grid to represent their views. Analyses group similar views (sorts). In this study, participants were selected from a range of types related to cybersecurity (experts, authorities and uninformed). Findings Four unique viewpoints emerged such that one represents cybersecurity best practices and the remaining three viewpoints represent poor cybersecurity behaviors (Naïve Cybersecurity Practitioners, Worried but not Vigilant and How is Cybersecurity a Big Problem) that indicate a need for educational interventions within both the public and private sectors. Practical implications Understanding the divergent views about cybersecurity is important within smaller groups including classrooms, technology-based college majors, a company, a set of IT professionals or other targeted groups where understanding cybersecurity viewpoints can reveal the need for training, changes in behavior and/or the potential for security breaches which reflect the human factors of cybersecurity. Originality/value A review of the literature revealed that only large, nation-wide surveys have been used to investigate views of cybersecurity. Yet, surveys are not useful in small groups, whereas Q is designed to investigate behavior through revealing subjectivity within smaller groups.

The effect of hand immersion on body temperature when wearing impermeable clothing

1991 ◽  
Vol 77 (1) ◽  
pp. 41-47
Author(s):  
A. J. Allsopp ◽  
Kerry A. Poole
Keyword(s):  
Body Temperature ◽  
Skin Temperature ◽  
Environmental Temperature ◽  
List Type ◽  
Physiological Measures ◽  
Total Work ◽  
Mean Skin Temperature ◽  
Work Time ◽  
Experimental Conditions ◽  
Rest Periods

AbstractThe effects of hand immersion on body temperature have been investigated in men wearing impermeable NBC clothing. Six men worked continuously at a rate of approximately 490 J.sec−1 in an environmental temperature of 30°C. Each subject was permitted to rest for a period of 20 minutes when their aural temperature reached 37.5°C, and again on reaching 38°C, and for a third time on reaching 38.5°C (three rest periods in total). Each subject completed three experimental conditions whereby, during the rest periods they either: a.Did not immerse their hands (control).b.Immersed both hands in a water bath set at 25°c.c.Immersed both hands in water at 10°C.Physiological measures of core temperature, skin temperature and heart rate were recorded at intervals throughout the experiment.Measures of mean aural temperature and mean skin temperature were significantly (P<0.05) reduced if hands were immersed during these rest periods, compared to non immersion. As a result, the total work time of subjects was extended when in the immersed conditions by some 10–20 minutes within the confines of the protocol.It is concluded that this technique of simple hand immersion may be effective in reducing heat stress where normal routes to heat loss are compromised.

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