137 research outputs found
The capability of capacitive sensors in the monitoring relative humidity in hypogeum environments
No full textHypogeum environments are characterized by high levels of relative humidity (RH).
Most humidity sensors currently in use are based on the capacitive effect of the dielectric material
to change according to water vapour uptake. In hypogeum environments the dielectric material
can be saturated by water vapor, implying a significant error in the RH measurement. To improve
the capacity of this type of humidity sensors, a modified hygrometer capacitive sensor, which
uses a heating cycle to avoid the condensation, has been recently developed by Rotronic®.
During four field campaigns in two different hypogea environments (the Monkey Tomb in Siena
and the Mithreum of Caracalla Baths in Rome), RH was measured using the conventional
capacitive sensor (CCS) and the heated capacitive sensor (HCS). The purpose of this study was
to investigate the capability of HCS to detect RH variations when the environmental conditions
were close to vapor saturation. Significant differences were found between the measurements of
the two sensors: when RH was close to 100%, the CCS was not able to detect the RH decrease,
giving only a measure of RH=100%, while HCS detected such a RH decrease. Therefore, these
results encourage the use of HCS in the monitoring of RH levels in extreme humidity sites such
as hypogea sites
Performance assessment of a heat and moisture dynamic simulation model in IDA ICE by the comparison with WUFI Plus
No full textRecently, in the field of preventive conservation, the use of accurate whole-building
dynamic simulation models is becoming an effective approach for preventing degradation
phenomena due to changes in indoor historic climate. Among microclimate parameters, the
moisture plays a key role in the degradation of organic-hygroscopic artworks as well as in the
durability of building components. Some simulation codes combine both heat and moisture
transfer calculations, however their capability to accurately model the moisture transport is
limited. The HMWall model coupled with IDA Indoor Climate and Energy (IDA ICE) software
is one of those models.
This study aims at comparing the performance of the HMWall model with respect to WUFI Plus,
developed by Fraunhofer Institute for Building Physics (IBP). Temperature (T) and relative
humidity (RH) provided by both codes in the case of a building envelope with no infiltration,
windows and incoming solar radiation, are compared. This allows to assess whether both models
calculate the moisture transport throughout walls in the same way. Dynamic simulations have
been run over a year by using different T-RH outdoor conditions. Even if both models are based
on the same heat and moisture transport equations, RH behaviour simulated by HMWall is
significantly different from that by WUFI Plus. This mainly depends on the calculation of
saturated vapour pressure (p sat ) inside the material. Then, the Common Exercise 3 has been
applied to test if HMWall were capable to affect indoor RH when cladding materials with
different sorption behaviour are used.
The new HMWall implemented model is resulted more effective than the previous one, and in
the case of simplified building, RHs modelled by both programs are highly correlated
Recensione di Hans-Christoph Schmidt am Busch, "„Anerkennung“ als Prinzip der Kritischen Theorie"
No full textRecensione di H.-C. Schmidt am Busch, „Anerkennung“ als Prinzip der Kritischen Theorie, Berlin, Boston: de Gruyter, 201
Hans-Christoph Schmidt am Busch, "„Anerkennung“ als Prinzip der Kritischen Theorie"
No full textRecensione di H.-C. Schmidt am Busch, „Anerkennung“ als Prinzip der Kritischen Theorie, Berlin, Boston: de Gruyter, 2011
Multi-year total ozone column variability at three Norwegian sites and the influence of Northern Hemisphere Climatic indices
No full textTotal ozone column (TOC) measurements are retrieved from the Ozone Monitoring Instrument (OMI) onboard the NASA Earth Observing System (EOS) Aura satellite at the three Norwegian sites: Oslo (59.9 degrees N 10.7 degrees E, 1 m a.s. l.), Trondheim (63.4 degrees N 10.4 degrees E, 3 m a.s.l.) and Andoya (69.1 degrees N 15.7 degrees E, 32 m a.s.l.). TOC data have been analysed from 2005 to 2021, in order to detect annual and multi-years total ozone variability. The relationship between geopotential height (GPH) at 250 hPa and total ozone column has been evaluated after showing that monthly anomalies in GPH and TOC are correlated amongst the three sites. The influence of the three Northern Hemisphere Tele Connection (TC) indices (North Atlantic Oscillation, Arctic Oscillation and Scandinavia) on TOC variability has been investigated. It is found that Scandinavia index plays a prominent role for the northernmost latitudes of Andoya and Trondheim while North Atlantic Oscillation and Arctic Oscillation indices are weakly correlated (negatively) to TOC and (positively) to GPH at Oslo. The response of TOC variability to the solar activity at the three sites is also explored and it is noticed that in the period of increasing variation of solar activity, significant TOC anomaly events are only observed in Andoya and Trondheim
Recensione di J. Schaub, Gerechtigkeit als Versöhnung. John Rawls politischer Liberalismus.
No full textRecensione del volume "Gerechtigkeit als Versöhnung. John Rawls politischer Liberalismus" di Jörg SCHAUB (Frankfurt am Main, Campus-Verlag, 2009
Investigation on the use of hygrothermal modelling for paper collections
No full textDynamic simulation is increasingly adopted in the preventive conservation of cultural heritage as an advanced method to investigate strategies for mitigating the climate-induced degradation. The conservation of paper collections is strongly interrelated with the relative humidity of the air, as organic-hygroscopic materials act as buffers on relative humidity fluctuations while being vulnerable to moisture-induced damage. In the dynamic simulation of the microclimate within library and archival storage facilities, it is thus fundamental to include the hygrothermal interaction between the building and its hygroscopic content. The hygroscopic behaviour of paper collections can be modelled by hygrothermal tools such as those of the HAM-family (Heat, Air and Moisture), used to simulate simultaneous heat and mass transfers through porous envelope materials. This research aims at investigating the use of the HMWall model coupled with the software IDA ICE (Indoor Climate and Energy) to simulate of the 1-D heat and moisture transfer through a single wall made of paper. A literature survey was carried out to collect the available hygrothermal properties of modern and historical papers. Sensitivity analysis was used to identify the most relevant hygrothermal parameters in the simulation of moisture gradients across the paper wall. Moreover, the number of sub-layers in the paper wall model was found to significantly affect the internal distribution of moisture gradients. The use of the HMWall model was then tested in the simulation of the hygroscopic behaviour of a single paper wall in both steady-state and transient conditions. Finally, a simplified model able to preserve the accuracy of the results was proposed with the purpose of reducing the computation effort that a high-resolution model could involve if implemented in whole buildings. This study represents the first step towards the application of the HMWall model for the simulation of the indoor climate of library repositories
Performance assessment of a heat and moisture dynamic simulation model in IDA ICE by the comparison with WUFI Plus
No full textRecently, in the field of preventive conservation, the use of accurate whole-building dynamic simulation models is becoming an effective approach for preventing degradation phenomena due to changes in indoor historic climate. Among microclimate parameters, the moisture plays a key role in the degradation of organic-hygroscopic artworks as well as in the durability of building components. Some simulation codes combine both heat and moisture transfer calculations, however their capability to accurately model the moisture transport is limited. The HMWall model coupled with IDA Indoor Climate and Energy (IDA ICE) software is one of those models. This study aims at comparing the performance of the HMWall model with respect to WUFI Plus, developed by Fraunhofer Institute for Building Physics (IBP). Temperature (T) and relative humidity (RH) provided by both codes in the case of a building envelope with no infiltration, windows and incoming solar radiation, are compared. This allows to assess whether both models calculate the moisture transport throughout walls in the same way. Dynamic simulations have been run over a year by using different T-RH outdoor conditions. Even if both models are based on the same heat and moisture transport equations, RH behaviour simulated by HMWall is significantly different from that by WUFI Plus. This mainly depends on the calculation of saturated vapour pressure (psat) inside the material. Then, the Common Exercise 3 has been applied to test if HMWall were capable to affect indoor RH when cladding materials with different sorption behaviour are used. The new HMWall implemented model is resulted more effective than the previous one, and in the case of simplified building, RHs modelled by both programs are highly correlated
A method based on environmental monitoring and building dynamic simulation to assess indoor climate control strategies in the preventive conservation within historical buildings
No full textThis paper proposes a multidisciplinary method to provide improved conservation strategy and thermal comfort for visitors in historical buildings. The method combines microclimate observations along with the dynamic simulation of the building and an empirical evaluation of the degradation of hygrosocopic artifacts. It was applied to a historic building in Priverno (Italy) where cracks along the tangential direction in valuable wooden ceilings were observed. The method produced an identification strategy for temperature control that, if applied, would reduce the total size of cracks from 0.25 mm to 0.10 mm
Genetic variants of Y chromosome are associated with a protective lipid profile in black men
No full textObjective— Gender and ethnicity modulate the phenotypic expression of cardiovascular risk factors. In particular, men are at higher risk of developing cardiovascular diseases compared to women, whereas black populations of African origin display reduced mortality from coronary heart disease (CHD) as compared to both whites and South Asians. Because the male-specific region (MSY) of the human Y chromosome is an obvious candidate for gender-related differences in the development of cardiovascular diseases, we aimed to identify genetic variants of MSY influencing cardiovascular risk profile in different ethnic groups.
Methods and Results— We genotyped 4 polymorphisms of MSY (HindIII±, rs768983 of TBL1Y, rs3212292 of USP9Y, and rs9341273 of UTY genes) in 579 men of different ethnic groups (blacks, South Asians, and whites) from UK and in 301 whites in Italy. We found that the TBL1YA USP9YA haplotype, present only in blacks in whom it represents the most frequent allelic combinations (AA: n=125; all other combinations: n=45), was associated with lower levels of triglycerides (P=0.025) and higher levels of HDL-cholesterol (P=0.005) as compared to the other haplotypes.
Conclusion— The TBL1YA USP9YA haplotype of the Y chromosome, present only in black people of African origin, attributes a favorable lipoprotein pattern, likely to contribute to their reduced susceptibility to coronary heart disease.
The study evaluated the association of genetic variants of the male-specific region of the Y chromosome with cardiovascular risk factors in different ethnic groups. The most frequently observed haplotype in black people was associated with a favorable lipoprotein pattern, thus contributing to the lower rate of cardiovascular diseases in blacks
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