LONG DISTANCE V.H.F. FIELDS: II. REFRACTIVITY PROFILES CONTAINING "SHARP LAYERS"

In this part the general solution developed in Part I is applied to the case in which the refractivity profile contains sharp layers (i.e. local regions where μ and dμ/dh change very rapidly compared with their rate of variation in a "standard" type atmosphere). It is found that such layers, when well developed, can cause distant fields of the order of magnitude of those which have been observed, but present experimental evidence seems to indicate that scattering from atmospheric turbulence is usually the important factor. An attempt is made to work out a physical interpretation of the field-formation below the elevated layer.

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LONG DISTANCE V.H.F. FIELDS: I. PARTIAL REFLECTION FROM A STANDARD ATMOSPHERE

Canadian Journal of Physics ◽

10.1139/p55-030 ◽

1955 ◽

Vol 33 (5) ◽

pp. 241-256 ◽

Cited By ~ 6

Author(s):

F. H. Northover

Keyword(s):

Atmospheric Turbulence ◽

High Power ◽

Electromagnetic Waves ◽

Effective Radius ◽

The Other ◽

Optical Range ◽

Long Distance ◽

Partial Reflection ◽

Standard Atmosphere ◽

Order Of Magnitude

Reliable propagation of V.H.F. waves and microwaves from high power transmitters to distances of several hundred miles beyond optical range has been demonstrated by an ever increasing number of experiments during the last ten years. The fields which have been observed have consistently been many times greater than the field strengths predicted by the "effective radius" theory. The present paper will be published in two parts. In Part I the theory that the phenomenon can be explained solely in terms of "partial internal reflection" from elementary layers of a dielectric distribution where the rate of decrease of (μ – 1) with height is everywhere continuous and of the same order of magnitude as in a "standard" atmosphere is carefully examined and found to be untenable. In Part II, the case where the distribution contains "sharp layers" (i.e., local regions where (μ – 1) changes relatively rapidly with height) is examined and it is found that these could cause the phenomenon. However, in view of the other characteristics of the observed field, it is concluded that the effect in question is probably more usually due to scattering of the electromagnetic waves from atmospheric turbulence.

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A Wave Resistance Formulation for Slender Bodies at Moderate to High Speeds

Journal of Ship Research ◽

10.5957/jsr.2012.56.4.207 ◽

2012 ◽

Vol 56 (04) ◽

pp. 207-214

Author(s):

Brandon M. Taravella ◽

William S. Vorus

Keyword(s):

General Solution ◽

High Speed ◽

Near Field ◽

Wave Resistance ◽

Slender Body ◽

Slender Body Theory ◽

Rates Of Change ◽

Order Of Magnitude ◽

Flow Variables ◽

Body Theory

T. Francis Ogilvie (1972) developed a Green's function method for calculating the wave profile of slender ships with fine bows. He recognized that near a slender ship's bow, rates of change of flow variables axially should be greater than those typically assumed in slender body theory. Ogilvie's result is still a slender body theory in that the rates of change in the near field are different transversely (a half-order different) than axially; however, the difference in order of magnitude between them is less than in the usual slender body theory. Typical of slender body theory, this formulation results in a downstream stepping solution (along the ship's length) in which downstream effects are not reflected upstream. Ogilvie, however, developed a solution only for wedge-shaped bodies. Taravella, Vorus, and Givan (2010) developed a general solution to Ogilvie's formulation for arbitrary slender ships. In this article, the general solution has been expanded for use on moderate to high-speed ships. The wake trench has been accounted for. The results for wave resistance have been calculated and are compared with previously published model test data.

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Talking Behind Your Back: Communication and Team Cooperation

Management Science ◽

10.1287/mnsc.2021.4143 ◽

2021 ◽

Author(s):

Klaus Abbink ◽

Lu Dong ◽

Lingbo Huang

Keyword(s):

Behavioral Economics ◽

Decision Analysis ◽

Experimental Evidence ◽

Team Communication ◽

Team Cooperation ◽

Profit Allocation ◽

Asymmetric Communication ◽

Present Experimental Evidence

Communication is one of the most effective devices in promoting team cooperation. However, asymmetric communication sometimes breeds collusion and hurts team efficiency. Here, we present experimental evidence showing that excluding one member from team communication hurts team cooperation; the communicating partners collude in profit allocation against the excluded member, and the latter reacts by exerting less effort. Allowing the partners to reach out to the excluded member partially restores cooperation and fairness in profit allocation, but it does not stop the partners from talking behind that member’s back even when they could have talked publicly. The partners sometimes game the system by tricking the excluded member into contributing but then grabbing all profits for themselves. This paper was accepted by Axel Ockenfels, behavioral economics and decision analysis.

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Moral Perceptions of Advised Actions

Management Science ◽

10.1287/mnsc.2018.3134 ◽

2019 ◽

Vol 65 (8) ◽

pp. 3904-3927 ◽

Cited By ~ 1

Author(s):

Lucas C. Coffman ◽

Alexander Gotthard-Real

Keyword(s):

Behavioral Economics ◽

Experimental Evidence ◽

Decision Makers ◽

Relational Contract ◽

Suggestive Evidence ◽

Present Experimental Evidence

Can an organization avoid blame for an unpopular action when an adviser advises it to do it? We present experimental evidence suggesting this is the case—advice to be selfish substantially decreases punishment of being selfish. Further, this result is true despite advisers’ misaligned incentives, known to all: Through a relational contract incentive, advisers are motivated to tell the decision makers what they want to hear. Through incentivized elicitations, we find suggestive evidence that advice moves punishment by affecting beliefs of how necessary the selfish action was. In follow-up treatments, however, we show advice does not decrease punishment solely through a beliefs channel. Advice not only changes beliefs about what happened, but also the perceived morality of it. Finally, in treatments in which advisers are available, the data suggest selfish decision makers act more selfishly. This paper was accepted by Axel Ockenfels, behavioral economics.

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Convergence and intonation: historical evidence from Buenos Aires Spanish

Bilingualism Language and Cognition ◽

10.1017/s1366728904001488 ◽

2004 ◽

Vol 7 (2) ◽

pp. 107-119 ◽

Cited By ~ 65

Author(s):

LAURA COLANTONI ◽

JORGE GURLEKIAN

Keyword(s):

Twentieth Century ◽

Experimental Evidence ◽

Buenos Aires ◽

Historical Evidence ◽

Contrastive Focus ◽

Italian Immigration ◽

Early Peak ◽

Intonational Phrases ◽

Pitch Accents ◽

Present Experimental Evidence

In this paper we present experimental evidence showing that Buenos Aires Spanish differs from other Spanish varieties in the realization of pre-nuclear pitch accents and in the final fall in broad focus declarative utterances. Whereas other Spanish varieties have been described consistently as showing late peak alignments, Buenos Aires Spanish displays early peak alignments. The alignment pattern found in Buenos Aires broad focus declarative utterances is not totally foreign to Spanish: it is attested in a quite different function, i.e. to signal contrastive focus. In addition, Buenos Aires Spanish also seems to differ from other Spanish varieties in the realization of the intonation contour in utterance-final intonational phrases, where a pronounced tendency for down-stepped peaks is observed. We argue that these patterns, which emerged at the turn of the twentieth century, and coincided with the peak of Italian immigration, are due to a combination of direct and indirect transfer from Italian. As a result, two intonational systems that were typologically similar before contact took place (Hualde, 2002) became more similar after contact, in what can be interpreted as a case of convergence.

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Research on influences of atmospheric turbulence on long-distance Fourier ptychographic imaging

Digital Optical Technologies 2019 ◽

10.1117/12.2525716 ◽

2019 ◽

Author(s):

Mingyang Yang ◽

Xuewu Fan ◽

Hui Zhao ◽

Chuang Li ◽

Meng Xiang

Keyword(s):

Atmospheric Turbulence ◽

Long Distance

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Comment on the X(3915) nonstandard hadron candidate

EPJ Web of Conferences ◽

10.1051/epjconf/201921202009 ◽

2019 ◽

Vol 212 ◽

pp. 02009 ◽

Cited By ~ 3

Author(s):

Stephen Lars Olsen

Keyword(s):

Experimental Evidence ◽

Decay Width ◽

Partial Decay Width ◽

Charmonium State ◽

Radial Excitation ◽

Order Of Magnitude

I review the experimental evidence for the X(3915), the candidate nonstandard meson associated with ωJ/ψ resonance-like peaks in B → KωJ/ψ and γγ → ωJ/ψ near M(ωJ/ψ) = 3920 MeV, and address the conjecture that it can be identified as the χ′c2, the radial excitation of the χc2 charmonium state. Since the partial decay width for B → KX(3915) is at least an order-of-magnitude higher than that for B → Kχc2, its assignment as the χ’c2 is dubious.

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A usage-based account of subextraction effects

Cognitive Linguistics ◽

10.1515/cog-2018-0135 ◽

2019 ◽

Vol 30 (4) ◽

pp. 719-750

Author(s):

Rui P. Chaves ◽

Adriana King

Keyword(s):

Artificial Intelligence ◽

Cognitive Science ◽

Experimental Evidence ◽

Framing Effect ◽

Complex Structures ◽

General Knowledge ◽

World Knowledge ◽

Long Distance ◽

The World ◽

Main Verb

Abstract The idea that conventionalized general knowledge – sometimes referred to as a frame – guides the perception and interpretation of the world around us has long permeated various branches of cognitive science, including psychology, linguistics, and artificial intelligence. In this paper we provide experimental evidence suggesting that frames also play a role in explaining certain long-distance dependency phenomena, as originally proposed by Deane (1991). We focus on a constraint that restricts the extraction of an NP from another NP, called subextraction, which Deane (1991) claims is ultimately a framing effect. In Experiment 1 we provide evidence showing that referents are extractable to the degree that they are deemed important for the proposition expressed by the utterance. This suggests that the world knowledge that the main verb evokes plays a key role in establishing which referents are extractable. In Experiment 2 we offer evidence suggesting that the acceptability of deep subextractions is correlated with the overall plausibility of the proposition, suggesting that complex structures can evoke complex frames as well, if sufficiently frequent and semantically coherent, and therefore more easily license deeper subextractions.

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Human Cooperation When Acting Through Autonomous Machines

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1817656116 ◽

2019 ◽

Vol 116 (9) ◽

pp. 3482-3487 ◽

Cited By ~ 9

Author(s):

Celso M. de Melo ◽

Stacy Marsella ◽

Jonathan Gratch

Keyword(s):

Experimental Evidence ◽

Paradigm Shift ◽

Autonomous Vehicles ◽

Short Term ◽

Collective Interest ◽

Intelligent Machines ◽

Cooperative Society ◽

Self Interest ◽

Autonomous Machines ◽

Present Experimental Evidence

Recent times have seen an emergence of intelligent machines that act autonomously on our behalf, such as autonomous vehicles. Despite promises of increased efficiency, it is not clear whether this paradigm shift will change how we decide when our self-interest (e.g., comfort) is pitted against the collective interest (e.g., environment). Here we show that acting through machines changes the way people solve these social dilemmas and we present experimental evidence showing that participants program their autonomous vehicles to act more cooperatively than if they were driving themselves. We show that this happens because programming causes selfish short-term rewards to become less salient, leading to considerations of broader societal goals. We also show that the programmed behavior is influenced by past experience. Finally, we report evidence that the effect generalizes beyond the domain of autonomous vehicles. We discuss implications for designing autonomous machines that contribute to a more cooperative society.

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