| 1. |
- Alametsä, Jarmo, et al.
(författare)
-
Age-related circulatory responses to whole body cooling: observations by ballistocardiographic EMFi sensors
- 2014
-
Ingår i: Proceedings of Ambience 14&10i3m : Scientific Conference for Smart and Functional Textiles, Well-Being, Thermal Comfort in Clothing, Design, Thermal Manikins and Modellin, 7-9 September 2014, Tampere, Finland - Scientific Conference for Smart and Functional Textiles, Well-Being, Thermal Comfort in Clothing, Design, Thermal Manikins and Modellin, 7-9 September 2014, Tampere, Finland. - 2342-4540. - 9789521532696 ; 1
-
Konferensbidrag (refereegranskat)abstract
- The purpose was to study age related changes in circulatory system via Ballistocardiography (BCG) by utilizing Electromechanical Film (EMFi) sensors by gradually changing the ambient temperature from a thermoneutral area to cold direction. ECG and BCG were recorded from a young person (23 years) and from an older person (78 years), both males. During the tests, brachium blood pressure (BP) and pulse signals were recorded from neck and ankle (with EMFi sensor strips). Thermal camera images were taken in order to find out temperature changes in whole body and limbs. Temporal durations and amplitudes of seat BCG:s components (systolic and diastolic) as well as from pulse signals from neck and ankle were calculated. Aortic pulse wave velocity (PWV) was obtained by utilizing the time between ECG’s R wave and maximum value of the ankle pulse signal. In both persons, the ankle pulse amplitude decreased when propagating to cold direction and increased in young person when returning to warmer ambient temperature. With young and old BCG:s systolic and diastolic temporal complexes remained stable, but systolic amplitudes increased in the older person (AHI 1.02 – 2.87, AIJ 0.7 – 2.66) as well as diastolic amplitudes (old; AKL 0.47 – 2.37). In the older person, PWV increased when moving to colder side. BP increased with a young person (from 95/64 to 132/75 mmHg), and with older person (from 125/68 to 176/101 mmHg) having a prominent rise in diastolic values during the cooling. The neck pulse wave amplitude AOP rise was modest with the younger person and had variation with the older person. Older person had also more intensive shivering compared to younger one. With the older person, the limbs stayed cold in thermal images when returning from cold to thermoneutral area. The present preliminary observations indicated clear age-related differences in the circulatory response to a mild whole-body thermal challenge.
|
|
| 2. |
- Aljaste, Helena, et al.
(författare)
-
Better bicycle helmets for commuters – evaluation of ventilation
- 2014
-
Ingår i: International Cycling Safety Conference 2014.
-
Konferensbidrag (refereegranskat)abstract
- As a continuation of the work on the development of setting the requirements for ventilation of a bicycle helmet for commuters, 15 full scale helmet mock-ups were created by the students of the Estonian Academy of Arts. In order to encourage creativity for ventilation solutions the students were not restricted to consider the other properties except it was pointed out that the meaning of helmets use is protection. These 1:1 scaled mock-ups were tested at Thermal Environment Laboratory, Lund University for their heat transfer characteristics (insulation) in a wind tunnel on a thermal head manikin. The helmets were tested at the room temperature with the air velocities of 0.2, 1.6 and 6.0 m/s. The air velocities of 0.2 and 1.6 m/s were tested without a wig and 1.6 and 6.0 m/s were tested with wig to simulate the effect of hair. In addition, 4 reference helmets were tested in some conditions. Three (3) of them were one of the best, one average and one of the less well performing helmets of an earlier study, and one was a helmet commonly bought and used by an ordinary bicyclist. The helmets in new design were affected by ventilation and covered a wide range of insula-tion. The reference helmets from the earlier study stayed quite in the middle of the tested range. Thus, the new solutions could work much better or worse than available helmets. However, practically any new helmet was better than the common helmet from the shop. It was also very clear that various air velocities affected heat loss from the helmets. This means that a best solution for a commuter has to be defined by the user’s bicycling velocity. The best ventilation solutions will be chosen and the design work with considering of impact testing will be continued.
|
|
| 3. |
- Broede, Peter, et al.
(författare)
-
The Universal Thermal Climate Index UTCI Compared to Ergonomics Standards for Assessing the Thermal Environment
- 2013
-
Ingår i: Industrial Health. - 1880-8026. ; 51:1, s. 16-24
-
Forskningsöversikt (refereegranskat)abstract
- The growing need for valid assessment procedures of the outdoor thermal environment in the fields of public weather services, public health systems, urban planning, tourism & recreation and climate impact research raised the idea to develop the Universal Thermal Climate Index UTCI based on the most recent scientific progress both in thermo-physiology and in heat exchange theory. Following extensive validation of accessible models of human thermoregulation, the advanced multi-node 'Fiala' model was selected to form the basis of UTCI. This model was coupled with an adaptive clothing model which considers clothing habits by the general urban population and behavioral changes in clothing insulation related to actual environmental temperature. UTCI was developed conceptually as an equivalent temperature. Thus, for any combination of air temperature, wind, radiation, and humidity, UTCI is defined as the air temperature in the reference condition which would elicit the same dynamic response of the physiological model. This review analyses the sensitivity of UTCI to humidity and radiation in the heat and to wind in the cold and compares the results with observational studies and internationally standardized assessment procedures. The capabilities, restrictions and potential future extensions of UTCI are discussed.
|
|
| 4. |
- Bröde, Peter, et al.
(författare)
-
Heat gain from thermal radiation through protective clothing with different insulation, reflectivity and vapour permeability
- 2010
-
Ingår i: International Journal of Occupational Safety and Ergonomics. - 2376-9130. ; 16:2, s. 231-244
-
Tidskriftsartikel (refereegranskat)abstract
- The heat transferred through protective clothing under long wave radiation compared to a reference condition without radiant stress was determined in thermal manikin experiments. The influence of clothing insulation and reflectivity, and the interaction with wind and wet underclothing were considered. Garments with different outer materials and colours and additionally an aluminised reflective suit were combined with different number and types of dry and pre-wetted underwear layers. Under radiant stress, whole body heat loss decreased, i.e., heat gain occurred compared to the reference. This heat gain increased with radiation intensity, and decreased with air velocity and clothing insulation. Except for the reflective outer layer that showed only minimal heat gain over the whole range of radiation intensities, the influence of the outer garments’ material and colour was small with dry clothing. Wetting the underclothing for simulating sweat accumulation, however, caused differing effects with higher heat gain in less permeable garments.
|
|
| 5. |
- Bröde, Peter, et al.
(författare)
-
Thermische Beanspruchung in Schutzkleidung
- 2010
-
Ingår i: Technische Überwachung. ; 51:6, s. 14-18
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract in German Grundlegende Daten zur Beurteilung der thermischen Beanspruchung während der Arbeit in Schutzkleidung wurden im europäischen Verbundprojekt THERMPROTECT (EU Contract-No. G6RD-CT-2002-00846) mit Untersuchungen des durch die Kleidung erhöhten Energieumsatzes und des Transports von Wärme und Feuchte unter Kältebelastung sowie bei Einwirkung von Wärmestrahlung erhoben. Der Eingang der hier dargestellten Resultate in international standardisierte Bewertungsverfahren soll zur Vermeidung thermophysiologischer Überbeanspruchungen beitragen.
|
|
| 6. |
- Czemiel Berndtsson, Justyna, et al.
(författare)
-
LTH - en attraktiv arbetsplats för både kvinnor och män?
- 2012
-
Ingår i: Ledarutvecklingsprogram för kvinnor och män vid Lunds universitet 2010-2011. - 9789163703522 ; AKKA IV, s. 115-145
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
|
|
| 7. |
|
|
| 8. |
- Gao, Chuansi, et al.
(författare)
-
Cooling vests with phase change material packs: the effects of temperature gradient, mass, and covering area
- 2010
-
Ingår i: Ergonomics. - : Informa UK Limited. - 0014-0139 .- 1366-5847. ; 53:5, s. 716-723
-
Tidskriftsartikel (refereegranskat)abstract
- Phase change material (PCM) absorbs or releases latent heat when it changes phases, making thermal-regulated clothing possible. The objective of this study was to quantify the relationships between PCM cooling rate and temperature gradient, mass, and covering area on a thermal manikin in a climatic chamber. Three melting temperatures (24, 28, 32 °C) of the PCMs, different mass, covering areas, and two manikin temperatures (34 and 38 °C) were used. The results showed that the cooling rate of the PCM vests tested is positively correlated with the temperature gradient between the thermal manikin and the melting temperature of the PCMs. The required temperature gradient is suggested to be greater than 6 °C when PCM vests are used in hot climates. With the same temperature gradient, the cooling rate is mainly determined by the covering area. The duration of the cooling effect is dependent on PCM mass and the latent heat
|
|
| 9. |
- Gao, Chuansi, et al.
(författare)
-
Cooling vests with phase change materials: the effects of melting temperature on heat strain alleviation in an extremely hot environment
- 2011
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6327 .- 1439-6319. ; 111:6, s. 1207-1216
-
Tidskriftsartikel (refereegranskat)abstract
- A previous study by the authors using a heated thermal manikin showed that the cooling rates of phase change material (PCM) are dependent on temperature gradient, mass, and covering area. The objective of this study was to investigate if the cooling effects of the temperature gradient observed on a thermal manikin could be validated on human subjects in extreme heat. The subjects wore cooling vests with PCMs at two melting temperatures (24 and 28°C) and fire-fighting clothing and equipment, thus forming three test groups (vest24, vest28 and control group without the vest). They walked on a treadmill at a speed of 5 km/h in a climatic chamber (air temperature = 55°C, relative humidity = 30%, vapour pressure = 4,725 Pa, and air velocity = 0.4 m/s). The results showed that the PCM vest with a lower melting temperature (24°C) has a stronger cooling effect on the torso and mean skin temperatures than that with a higher melting temperature (28°C). Both PCM vests mitigate peak core temperature increase during the resting recovery period. The two PCM vests tested, however, had no significant effect on the alleviation of core temperature increase during exercise in the heat. To study the possibility of effective cooling of core temperature, cooling garments with PCMs at even lower melting temperatures (e.g. 15°C) and a larger covering area should be investigated.
|
|
| 10. |
|
|
