CO2 Concentration and Occupants’ Symptoms in Naturally Ventilated Schools in Mediterranean Climate

A large part of the school building stock in Andalusia lacks ventilation facilities, so that the air renewal of the classrooms is achieved through the building envelope (air infiltration) or the opening of windows. This research analyses the airtightness of the classrooms in Andalusia and the evolution of CO2 concentration during school hours through in situ monitoring. Pressurization and depressurization tests were performed in 42 classrooms and CO2 concentration was measured in two different periods, winter and midseason, to study the impact of the different levels of aperture of windows. About 917 students (11–17 years of age) were surveyed on symptoms and effects on their health. The mean n50 values are about 7 h−1, whereas the average CO2 concentration values are about 1878 ppm, with 42% of the case studies displaying concentrations above 2000 ppm with windows closed.

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Optimal Renovation Strategies through Life-Cycle Analysis in a Pilot Building Located in a Mild Mediterranean Climate

Applied Sciences ◽

10.3390/app11041423 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1423

Author(s):

José Manuel Salmerón Lissen ◽

Cristina Isabel Jareño Escudero ◽

Francisco José Sánchez de la Flor ◽

Miriam Navarro Escudero ◽

Theoni Karlessi ◽

...

Keyword(s):

Life Cycle ◽

Life Cycle Cost ◽

Mediterranean Climate ◽

Building Envelope ◽

Economic Life ◽

Hot Water ◽

Optimal Solutions ◽

Building Stock ◽

Existing Building ◽

The Cost

The 2030 climate and energy framework includes EU-wide targets and policy objectives for the period 2021–2030 of (1) at least 55% cuts in greenhouse gas emissions (from 1990 levels); (2) at least 32% share for renewable energy; and (3) at least 32.5% improvement in energy efficiency. In this context, the methodology of the cost-optimal level from the life-cycle cost approach has been applied to calculate the cost of renovating the existing building stock in Europe. The aim of this research is to analyze a pilot building using the cost-optimal methodology to determine the renovation measures that lead to the lowest life-cycle cost during the estimated economic life of the building. The case under study is an apartment building located in a mild Mediterranean climate (Castellon, SP). A package of 12 optimal solutions has been obtained to show the importance of the choice of the elements and systems for renovating building envelopes and how energy and economic aspects influence this choice. Simulations have shown that these packages of optimal solutions (different configurations for the building envelope, thermal bridges, airtightness and ventilation, and domestic hot water production systems) can provide savings in the primary energy consumption of up to 60%.

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IN SITU MONITORING OF MEAN BLOOD OXYGEN SATURATION USING EXTENDED MODIFIED LAMBERT BEER MODEL

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237215500040 ◽

2015 ◽

Vol 27 (01) ◽

pp. 1550004 ◽

Cited By ~ 2

Author(s):

Audrey K. C. Huong ◽

Xavier T. I. Ngu

Keyword(s):

Oxygen Saturation ◽

In Situ Monitoring ◽

Blood Oxygen ◽

Optical Monitoring ◽

Hypertension Status ◽

Blood Oxygen Saturation ◽

Fitting Procedure ◽

Arterial Blood ◽

The Mean

We present the use of Extended Modified Lambert–Beer model for optical monitoring of mean blood oxygen saturation ( S m O 2) via a fitting procedure. This work focuses on the absorption characteristics of hemoglobin derivatives in the wavelength range of 520–600 nm to give the best estimates of S m O 2. The study of the feasibility of applying this analytic method to skin oximetry is via spectroscopy data collected from fingertips of four healthy volunteers both at rest and during arterial blood occlusion condition. The results revealed a decrease in the mean of mean and standard deviation of S m O 2 value of fingertips from 94.5 ± 2.19% when volunteers were at rest to 56.76 ± 5.8% during the arterial blood occlusion measurement. The larger variation in the value estimated for blood occlusion condition could be a result of differences in volunteers' physical fitness and hypertension status. These estimated S m O 2 values agreed reasonably well with the value reported in most of the previous studies. This work concluded that the proposed technique can potentially be used as a complementary technique to clinical assessment of skin grafts and burnt skin.

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Fuel economy assessment tool for auxiliary kite propulsion of merchant ship

La Houille Blanche ◽

10.1051/lhb/2018001 ◽

2018 ◽

pp. 5-7 ◽

Cited By ~ 1

Author(s):

Vincent Podeur ◽

Damien Merdrignac ◽

Morgan Behrel ◽

Kostia Roncin ◽

Caroline Fonti ◽

...

Keyword(s):

Fuel Economy ◽

Assessment Tool ◽

Round Trip ◽

Merchant Ship ◽

Added Resistance In Waves ◽

The Mean ◽

The Impact ◽

Engine Power

A tool dedicated to assess fuel economy induced by kite propulsion has been developed. To produce reliable results, computations must be performed on a period over several years, for several routes and for several ships. In order to accurately represent the impact of meteorological trends variations on the exploitability of the kite towing concept, a time domain approach of the problem has been used. This tool is based on the weather database provided by the ECMWF. Two sailing strategies can be selected for assessing the performance of the kite system. For a given kite area, the simulation can be run either at constant speed or at constant engine power. A validation has been made, showing that predicted consumption is close from in-situ measurement. It shows an underestimation of 11.9% of the mean fuel consumption mainly due to auxiliary consumption and added resistance in waves that were not taken into account. To conclude, a case study is performed on a 2200 TEU container ship equipped with an 800m² kite on a transatlantic route between Halifax and Le Havre. Round trip simulations, performed over 5 years of navigation, show that the total economy predicted is of around 12% at a speed of 16 knots and around 6.5% at a speed of 19 knots.

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Stability Assessment of Mining Excavations: the Impact of Large Depths

Studia Geotechnica et Mechanica ◽

10.2478/sgem-2018-0021 ◽

2018 ◽

Vol 40 (3) ◽

pp. 180-187

Author(s):

Tadeusz Majcherczyk ◽

Zbigniew Niedbalski ◽

Łukasz Bednarek

Keyword(s):

Rock Mass ◽

In Situ Monitoring ◽

Stability Assessment ◽

Underground Excavations ◽

Deformation Prediction ◽

Large Depth ◽

Coal Deposits ◽

The Impact

AbstractBack in the early 1980s, coal deposits occurring at depths of ~700 m below surface were already regarded as large-depth deposits. Meanwhile, today the borderline depth of large-depth mining has extended to >1,000 m. Design, excavation and maintenance of mining roadways at the depth of >1,000 m have, therefore, become crucial issues in a practical perspective in recent years. Hence, it is now extremely important to intensify research studies on the influence of large depths on the behaviour of rock mass and deformation of support in underground excavations. The paper presents the results of the study carried out in five mining excavations at depths ranging from 950 to 1,290 m, where monitoring stations with measurement equipment were built. The analysis of data from laboratory and coal mine tests, as well as in situ monitoring, helped to formulate a set of criteria for stability assessment of underground excavations situated at large depths. The proposed methodology of load and deformation prediction in support systems of the excavations unaffected by exploitation is based on the criteria referring to the depth of excavation and the quality of rock mass. The depth parameter is determined by checking whether the analysed excavation lies below the critical depth, whereas the rock mass quality is determined on the basis of the roof lithology index (WL) and the crack intensity factor (n)

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In Situ Monitoring of Drying Process of Masonry Walls

Energies ◽

10.3390/en13236190 ◽

2020 ◽

Vol 13 (23) ◽

pp. 6190

Author(s):

Łukasz Cieślikiewicz ◽

Piotr Łapka ◽

Radosław Mirowski

Keyword(s):

Energy Consumption ◽

Moisture Content ◽

Thermal Behavior ◽

Specific Energy Consumption ◽

Masonry Wall ◽

In Situ Monitoring ◽

Drying Process ◽

Final State ◽

The Mean

The in situ hygro-thermal behavior of a wet masonry wall during its drying process is presented in this paper. The considered wall is a part of a basement of a historic building that was subjected to renovation works. The building is located in the City of Łowicz (Poland). The drying process was implemented by applying the thermo-injection method and a novel prototype of the drying device used for this method. The dedicated acquisition system was developed to in situ monitor parameters of the drying process. The air temperature and relative humidity in various locations in the basement, temperatures and moisture contents at several points of the wet wall as well as the electrical parameters of the drying device were registered. Based on variations of the monitored parameters, the hygro-thermal behavior of the wall during drying was studied. After 6 days of drying, the wall temperature in the drying zone was increased to approximately 40–55 °C, while the moisture content was reduced to the mean level of 3.76% vol. (2.35% wt.). These wall parameters allowed for effective impregnation of the wall with the hydrophobic silicone micro-emulsion, which created horizontal and vertical waterproofing. Moreover, the specific energy consumption during the drying process defined as energy consumption divided by the mean volumetric moisture content drop (MC) between the initial and final state in the wall and by the length of the dried wall section was estimated to be 11.08 kWh/MC%/m.

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What Is the Impact of Additional Tropical Observations on a Modern Data Assimilation System?

Monthly Weather Review ◽

10.1175/mwr-d-18-0120.1 ◽

2019 ◽

Vol 147 (7) ◽

pp. 2433-2449

Author(s):

Laura C. Slivinski ◽

Gilbert P. Compo ◽

Jeffrey S. Whitaker ◽

Prashant D. Sardeshmukh ◽

Jih-Wang A. Wang ◽

...

Keyword(s):

El Niño ◽

Large Scale ◽

El Nino ◽

Mean Square ◽

Observational Network ◽

In Situ Observations ◽

The Mean ◽

The Impact ◽

Assimilation System

Abstract Given the network of satellite and aircraft observations around the globe, do additional in situ observations impact analyses within a global forecast system? Despite the dense observational network at many levels in the tropical troposphere, assimilating additional sounding observations taken in the eastern tropical Pacific Ocean during the 2016 El Niño Rapid Response (ENRR) locally improves wind, temperature, and humidity 6-h forecasts using a modern assimilation system. Fields from a 50-km reanalysis that assimilates all available observations, including those taken during the ENRR, are compared with those from an otherwise-identical reanalysis that denies all ENRR observations. These observations reveal a bias in the 200-hPa divergence of the assimilating model during a strong El Niño. While the existing observational network partially corrects this bias, the ENRR observations provide a stronger mean correction in the analysis. Significant improvements in the mean-square fit of the first-guess fields to the assimilated ENRR observations demonstrate that they are valuable within the existing network. The effects of the ENRR observations are pronounced in levels of the troposphere that are sparsely observed, particularly 500–800 hPa. Assimilating ENRR observations has mixed effects on the mean-square difference with nearby non-ENRR observations. Using a similar system but with a higher-resolution forecast model yields comparable results to the lower-resolution system. These findings imply a limited improvement in large-scale forecast variability from additional in situ observations, but significant improvements in local 6-h forecasts.

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In situ monitoring of internal surface temperature of the historic building envelope

Selected Scientific Papers - Journal of Civil Engineering ◽

10.1515/sspjce-2016-0009 ◽

2016 ◽

Vol 11 (1) ◽

pp. 77-84

Author(s):

Veronika Labovská ◽

Dušan Katunský

Keyword(s):

Surface Temperature ◽

Internal Surface ◽

Building Envelope ◽

In Situ Monitoring ◽

Heat Accumulation ◽

Historical Building ◽

External Temperature ◽

Inner Surface ◽

Real Behavior

Abstract Historical building envelope is characterized by a large accumulation that impact is mainly by changing the inner surface temperature over time. The minimum value of the inner surface temperature is set Code requirements. In the case of thermal technology assessment of building envelope contemplates a steady state external temperature and internal environment, thereby neglecting the heat accumulation capacity of building envelopes. Monitoring surface temperature in real terms in situ shows the real behavior of the building envelope close to reality. The recorded data can be used to create a numerical model for the simulation.

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Stochastic simulation of rain intrusion through small defects due to water rivulet overpressure. Introducing a driving rain leakage potential

Journal of Physics Conference Series ◽

10.1088/1742-6596/2069/1/012052 ◽

2021 ◽

Vol 2069 (1) ◽

pp. 012052

Author(s):

C.-E. Hagentoft ◽

L. Olsson

Keyword(s):

Building Envelope ◽

Wind Pressure ◽

Weather Data ◽

Wall Structure ◽

Building Stock ◽

Major Threat ◽

The Mean ◽

The Cost ◽

Interior Side ◽

Driving Rain

Abstract There is a need of upgrading the old building stock with respect to the thermal insulation of the building envelope and specifically the façades. There are several systems on the market, and some are quite new and innovative. To bring down the cost some of the systems many are based on prefabricated moisture tight insulated units. This means that in case there is moisture tight barrier on the interior side, two moisture tight barriers surround the wall structure. The leakage of driving rain into the structure then represents a major threat to the durability of these systems. This paper investigates the pressure build up in water rivulets running down a façade acting together with the wind pressure. A driving rain leakage potential is introduced. Using real weather data years and Monte Carlo Simulations, the mean and standard deviation of the annual leakage through small hole is estimated. The examples show that the leakage can reach a level 0-0.5 liter/year for a hole with a diameter of 1-2 mm, and 0.5-3 liter/year for a diameter of 3-4 mm.

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Comparative Study on in-situ Ellipsometric Monitoring of III-Nitride Film Growth via Plasma-Enhanced Atomic Layer Deposition

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156419400202 ◽

2019 ◽

Vol 28 (03n04) ◽

pp. 1940020

Author(s):

Adnan Mohammad ◽

Deepa Shukla ◽

Saidjafarzoda Ilhom ◽

Brian Willis ◽

Ali Kemal Okyay ◽

...

Keyword(s):

Growth Rate ◽

Real Time ◽

Film Growth ◽

Atomic Layer ◽

Layer Growth ◽

In Situ Monitoring ◽

Rf Plasma ◽

Nitride Film ◽

The Impact

In this paper a comparative in-situ ellipsometric analysis is carried out on plasma-assisted ALD-grown III-nitride (AlN, GaN, and InN) films. The precursors used are TMA, TMG, and TMI for AlN, GaN, and InN respectively, while Ar is used as purge gas. For all of the films N2/H2/Ar plasma was used as the co-reactant. The work includes real-time in-situ monitored saturation curves, unit ALD cycle analysis, and >500 cycle film growth runs. In addition, the films are grown at different substrate temperatures to observe the impact of temperature not only on the growth rate but on how it influenced the precursor chemisorption, ligand removal, and nitrogen incorporation surface reactions. All three nitride films confirm fairly linear growth character. The growth rate per cycle (GPC) for each film is also measured with respect to rf-plasma power to obtain the surface saturation conditions during ALD growth. The real-time in-situ monitoring of the film growth can really be beneficial to understand the atomic layer growth and film formation in each individual ALD cycle.

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Towards Remote Sensing of Atmospheric Trace Gases in the UV spectral range using Dual-Comb spectroscopy

10.5194/egusphere-egu21-12337 ◽

2021 ◽

Author(s):

Clément Pivard ◽

Sandrine Galtier ◽

Patrick Rairoux

Keyword(s):

Remote Sensing ◽

Spectral Range ◽

Near Infrared ◽

Frequency Comb ◽

Trace Gases ◽

In Situ Monitoring ◽

Atmospheric Trace Gases ◽

The Impact ◽

Uv Range

The development of increasingly sensitive and robust instruments and new methodologies are essential to improve our understanding of the Earth&#8217;s climate and air pollution. In this context, Dual-Comb spectroscopy (DCS) appears as an emerging spectroscopy methodology to detect in situ, without air-sampling, atmospheric trace-gases.DCS is a Fourier-transform type experiment that takes advantage of mode-locked femtosecond (fs) pulses. This methodology appears highly relevant for atmosphere remote-sensing studies because of its very fast acquisition rate (>kHz) that reduces the impact of atmospheric turbulences on the retrieved spectra. DCS has been successfully applied in near-infrared (NIR) spectral ranges for atmospheric greenhouse gas monitoring (water vapor, carbon dioxide, and methane) [1-2].Its implementation in the UV range would offer a new spectroscopic intrumentation to target the most reactive species of the atmosphere (OH, HONO, BrO...) as they have their greatest absorption cross-sections in the UV range. UV-DCS would therefore be an answer to the lack of variability of today operationnal and in situ monitoring instrument for those reactive molecules.We will present a potential light source for remote sensing UV-DCS and discuss the degree of immunity of UV-DCS to atmospheric turbulences. We will show to which extent the characteristics of the currently available UV sources are compatible with the unambiguous identification of UV absorbing gases by UV-DCS. We will finally present the performances of UV-DCS in terms of concentration detection limit for several UV absorbing molecules (OH, BrO, NO2, OClO, HONO, CH2O, SO2). This sensitivity study has been recently published [3] and the main results will be presented.&#160;[1] Rieker, G.B.; Giorgetta, F.R.; Swann, W.C.; Kofler, J.; Zolot, A.M.; Sinclair, L.C.; Baumann, E.; Cromer, C.;Petron, G.; Sweeney, C.; et al. &#171; Frequency-comb-based remote sensing of greenhouse gases over kilometer air Paths&#160;&#187;. Optica 1, p. 290&#8211;298 (2014)[2] Oudin, J.; Mohamed, A.K.; H&#233;bert, P.J. "IPDA LIDAR measurements on atmospheric CO2 and H2O using dual comb spectroscopy," Proc. SPIE 11180, International Conference on Space Optics &#8212; ICSO 2018, p. 111802N (12 July 2019)[3] Galtier, S.; Pivard, C.; Rairoux, P. Towards DCS in the UV Spectral Range for Remote Sensing of Atmospheric Trace Gases.&#160;Remote Sens.,&#160;12, p.3444 (2020)

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