Demand-controlled ventilation in schools: Influence of base ventilation rates on subjective symptoms, perceived indoor environment and young adults' learning performance

The ventilation airflow rates in a demand-controlled ventilation strategy typically vary between a base (Vmin) and a maximum ventilation rate (Vmax). Classrooms have relatively short but intense hours of occupancy and a low Vmin can result in high energy savings. Our study aims to examine how different Vmin (1.1 versus 2.0 l/s per m²) affect subjective symptoms, perceived indoor environment quality (IEQ), and performance for young adults. Symptom intensity and perceived IEQ were recorded on a visual scale, and performance was examined by identifying three different letters in a nonsense text. Tests were done immediately after entering the classroom. We found no significant effects of increasing Vmin from 1.1 to 2.0 l/s per m² on learning performance, symptoms, or perceived IEQ.publishedVersio

A Numerical Analysis Approach For Estimating The Minimum Traveling Wave Speed For An Autocatalytic Reaction

This thesis studies the traveling wavefront created by the autocatalytic cubic chemical reaction A + 2B → 3B involving two chemical species A and B, where A is the reactant and B is the auto-catalyst. The diffusion coefficients for A and B are given by DA and DB. These coefficients differ as a result of the chemical species having different size and/or weight. Theoretical results show there exist bounds, v* and v*, depending on DB/DA, where for speeds v ≥ v*, a traveling wave solution exists, while for speeds v \u3c v*, a solution does not exist. Moreover, if DB ≤ DA, and v* and v* are similar to one another and in the order of DB/DA when it is small. On the other hand, when DA ≤ DB there exists a minimum speed vmin, such that there is a traveling wave solution if the speed v \u3e vmin. The determination of vmin is very important in determining the dynamics of general solutions. To fill in the gap of the theoretical study, we use numerical methods to determine vmin for various cases. The numerical algorithm used is the fourth-order Runge-Kutta method (RK4)

Fully-Digital Rail-to-Rail OTA with Sub-1,000 μm2 Area, 250-mV Minimum Supply and nW Power at 150-pF Load in 180nm

A fully-digital operational transconductance amplifier (DIGOTA) architecture for tightly energy-constrained low-cost systems is presented. A 180nm DIGOTA testchip exhibits an area below the 1,000-μm2 wall, and 2.4-nW power under 150pF load, and a minimum supply voltage Vmin of 0.25 V. In the 0.3-0.5 V supply range, DIGOTA improves the areanormalized small (large) signal energy FoM by at least 836X (267X) over prior sub-500mV OTAs, while reducing area by 27-85X. The low-Vmin and nW-power features are shown to enable direct harvesting at the mm scale

Assessing Compatibility of Direct Detection Data: Halo-Independent Global Likelihood Analyses

We present two different halo-independent methods to assess the compatibility of several direct dark matter detection data sets for a given dark matter model using a global likelihood consisting of at least one extended likelihood and an arbitrary number of Gaussian or Poisson likelihoods. In the first method we find the global best fit halo function (we prove that it is a unique piecewise constant function with a number of down steps smaller than or equal to a maximum number that we compute) and construct a two-sided pointwise confidence band at any desired confidence level, which can then be compared with those derived from the extended likelihood alone to assess the joint compatibility of the data. In the second method we define a "constrained parameter goodness-of-fit" test statistic, whose $p$-value we then use to define a "plausibility region" (e.g. where $p \geq 10\%$). For any halo function not entirely contained within the plausibility region, the level of compatibility of the data is very low (e.g. $p < 10 \%$). We illustrate these methods by applying them to CDMS-II-Si and SuperCDMS data, assuming dark matter particles with elastic spin-independent isospin-conserving interactions or exothermic spin-independent isospin-violating interactions.Comment: 31 pages, 6 figures. V2: Modified several paragraphs to improve clarify. Modified Fig. 5 and added Fig. 6 to further illustrate methods of Section 5. Added proof of uniqueness of best fit halo function in Appendix