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A pilot test of daylighting and electric lighting to address visual and non-visual requirements

Advancements in understanding the non-visual effects of light have sparked interest in using lighting to promote circadian entrainment. Circadian design metrics like melanopic equivalent daylight illuminance (mEDI) are now being adopted with proposed target values. Traditional lighting design, focused on horizontal illumination for visual needs, falls short for circadian lighting design which shou

Testing an experiential learning approach to building performance simulations

Novices often find learning building performance simulation (BPS) overwhelming, juggling theory, simulation tools, and result interpretation simultaneously. We applied Beausoleil-Morrison's conceptualization of Kolb's experiential learning approach to BPS. Testing it in a master course, we observed enhanced critical thinking, problem-solving, and skill development. Here we discuss the process lead

Global Bifurcation and Highest Waves on Water of Finite Depth

We consider the two-dimensional problem for steady water waves with vorticity on water of finite depth. While neglecting the effects of surface tension we construct connected families of large amplitude periodic waves approaching a limiting wave, which is either a solitary wave, the highest solitary wave, the highest Stokes wave or a Stokes wave with a breaking profile. In particular, when the vor

On the amplitude and the flow force constant of steady water waves

We prove a new explicit inequality for the non-dimensional flow force constant, significantly improving the Benjamin and Lighthill conjecture about irrotational steady water waves. As a corollary, we prove a bound for the wave amplitude in terms of the Bernoulli constant. We show that the amplitude decays as r−2 when r→+∞, where r is the non-dimensional Bernoulli constant. We explain that the latt

Nonexistence of Subcritical Solitary Waves

We prove the nonexistence of two-dimensional solitary gravity water waves with subcritical wave speeds and an arbitrary distribution of vorticity. This is a longstanding open problem, and even in the irrotational case there are only partial results relying on sign conditions or smallness assumptions. As a corollary, we obtain a relatively complete classification of solitary waves: they must be sup

Solitary waves on constant vorticity flows with an interior stagnation point

The two-dimensional free-boundary problem describing steady gravity waves with vorticity on water of finite depth is considered. Under the assumption that the vorticity is a negative constant whose absolute value is sufficiently large, we construct a solution with the following properties. The corresponding flow is unidirectional at infinity and has a solitary wave of elevation as its upper bounda

On bounds for steady waves with negative vorticity

We prove that no two-dimensional Stokes and solitary waves exist when the vorticity function is negative and the Bernoulli constant is greater than a certain critical value given explicitly. In particular, we obtain an upper bound F≤2+ϵ for the Froude number of solitary waves with a negative constant vorticity, sufficiently large in absolute value.

N-Modal Steady Water Waves with Vorticity

Two-dimensional steady gravity driven water waves with vorticity are considered. Using a multidimensional bifurcation argument, we prove the existence of small-amplitude periodic steady waves with an arbitrary number of crests per period. The role of bifurcation parameters is played by the roots of the dispersion equation.

On the Benjamin-Lighthill conjecture for water waves with vorticity

We consider the nonlinear problem of steady gravity-driven waves on the free surface of a two-dimensional flow of an inviscid, incompressible fluid (say, water). The water motion is supposed to be rotational with a Lipschitz continuous vorticity distribution, whereas the flow of finite depth is assumed to be unidirectional. We verify the Benjamin-Lighthill conjecture for flows with values of Berno

On bounds and non-existence in the problem of steady waves with vorticity

For the problem describing steady gravity waves with vorticity on a two-dimensional unidirectional flow of finite depth the following results are obtained. (i) Bounds are found for the free-surface profile and for Bernoulli's constant. (ii) If only one parallel shear flow exists for a given value of Bernoulli's constant, then there are no wave solutions provided the vorticity distribution is subje

Steady water waves with vorticity : An analysis of the dispersion equation

Two-dimensional steady gravity waves with vorticity are considered on water of finite depth. The dispersion equation is analysed for general vorticity distributions, but under assumptions valid only for unidirectional shear flows. It is shown that for these flows (i) the general dispersion equation is equivalent to the Sturm-Liouville problem considered by Constantin & Strauss (Commun. Pure Ap

Maximal functions measuring smoothness : Counterexamples

We consider two main maximal operators measuring smoothness. For all possible values of the parameters, we give simple examples of bounded compactly supported functions that show quite clearly the difference between these maximal operators. Bibliography: 3 titles.

Gagliardo-Nirenberg inequality for maximal functions measuring smoothness

We prove a Galiardo-Nirenberg type pointwise interpolation inequality for special maximal functions which measure smoothness in the multidimensional case. It turns out that the classsical inequality follows from this one; it is also possible to use naturally BMO norms in the inequality. Bibliography: 6 titles.

Details Matter : Secluded Areas and Voting Secrecy with French Ballots

To explore the psychology of voting secrecy, we conducted a field experiment to examine voter sensitivity to arrangements for ballot paper selection under the French ballot system (i.e., multiple ballot papers). Working closely with Swedish election authorities, we randomly assigned participants to vote in a fictional election under low, medium-high and high privacy conditions with a follow up pap