The aeolian threshold condition is identified as defining the critical state between a static sediment bed and active aeolian transport. Disparities in reported mean threshold shear velocities (U*T) are attributed to variation in: (a) flow regimes; (b) entrainment criteria; (c) particle characteristics and exposures; and (d) techniques for measurement of 1*T The relative significance of these factors is assessed for strips and beds of ballotini, aeolian sand, salt crystals and sugar crystals using the controlled, reproducible flow conditions of the developing boundary layer over a flat plate. Such a plate was covered with a non-erosive layer of grains to simulate a flat sediment bed and was positioned in a wind tunnel. values were calculated using the momentum integral method. In a separate study, threshold conditions on impervious and permeable beds were compared directly. Analysis of entrainment from strips and beds on the plate shows that the threshold condition is principally determined by a critical degree of overlap between the probability distributions of local shear velocity, P ( U ), and of grain threshold shear velocity, P(U*T). Characteristic P(U*T) distributions for test materials were determined and two objective definitions of U*T were devised. Experimental *T values agree well with published data and are used to resolve the data scatter associated with both 'restricted' and 'universal' threshold curves. Rates of aeolian entrainment over a range of values are found to be an inverse exponential function of time and wind speed. Different erosion rates were found to result from skewness of P(U) and degree of overlap between P(U) and P(U*T). Fluid sweeps in the turbulent bursting cycle are considered to be the primary entrainment mechanism. Medium/high-speed cine film gave insight into initiation processes. Grain oscillation due to vortex shedding and initial motion characterized by a progressive rolling and bouncing were observed. Bed permeability was not found to affect aeolian threshold values.

A challenge in Underwater Acoustics is identifying the independent variables associated with an environment’s ambient noise. A strict definition of ambient noise would focus on non-transient signatures and exclude transient impacts from marine mammals, pelagic fish species, man-made sources, or weather events such as precipitation or wind speeds. Recognizing transient signatures in acoustic spectra is an essential element for providing environmental intelligence to the U.S. Navy, specifically the acoustic signatures from meteorological events. While weather event detection in acoustic spectra has been shown in previous studies, leveraging these concepts via U.S. Navy assets is largely an unknown. Environmental intelligence collection can be improved by detecting precipitation events and establishing wind velocities with acoustic signatures. This will further improve meteorological models by enabling validation from both manned and unmanned sub-surface assets.

Visual field testing, or perimetry, measures peripheral visual loss in eye diseases such as glaucoma. Rarebit Perimetry (RBP) is a new and novel perimetric method, introduced in 2002 by Lars Frisén (2002), with the aim of detecting low degrees of neural damage within the retina. / RBP is unlike conventional perimetric methods that measure levels of retinal sensitivity, but instead uses very bright (i.e. suprathreshold) and very small targets to detect tiny areas of absolute blindness within otherwise normal areas of vision. RBP thus claims to locate miniscule gaps in the receptive field matrix of neurons in the retina, with the assumption that dead neurons leave gaps in this matrix. The most useful application of this idea is to detect progressive eye disease in the earliest stages (Frisén, 2002). Current research shows that RBP correlates with other standard visual field tests (Brusini, Salvetat, et al., 2005; Frisén, 2003; Gedik, Akman, et al., 2007; Martin & Wanger, 2004), but may afford greater sensitivity by detecting very mild visual losses missed by other tests (Martin, Ley, et al., 2004; Martin & Nilsson, 2007; Nilsson, Wendt, et al., 2007). / To date, there are no studies that definitively test the theoretical basis of RBP, so in this thesis I aim to explore the proposed underlying mechanisms and assumptions of this test. In particular, the proposed mechanism of RBP leads to specific predictions as to how responses will alter when the luminances of the RBP targets are systematically decreased. I therefore compared RBP responses of mean hit rate as a function of target luminance and found results to be inconsistent with the proposed RBP mechanism. Mathematical simulations were performed to explore reasons for the differences between the two groups (Chapter Seven).

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Iterative decoding and codes on graphs were first devised by Gallager in 1960, and then rediscovered by Berrou, Glavieux and Thitimajshima in 1993. This technique plays an important role in modern communications, especially in coding theory and practice. In particular, low-density parity-check (LDPC) codes, introduced by Gallager in the 1960s, are the class of codes at the heart of iterative coding. Since these codes are quite general and exhibit good performance under message-passing decoding, they play an important role in communications research today. A thorough analysis of iterative decoding systems and the relationship between maximum a posteriori (MAP) and belief propagation (BP) decoding was initiated by Measson, Montanari, and Urbanke. This analysis is based on density evolution (DE), and extrinsic information transfer (EXIT) functions, introduced by ten Brink. Following their work, this thesis considers the MAP decoding thresholds of three iterative decoding systems. First, irregular repeat-accumulate (IRA) and accumulaterepeataccumulate (ARA) code ensembles are analyzed on the binary erasure channel (BEC). Next, the joint iterative decoding of LDPC codes is studied on the dicode erasure channel (DEC). The DEC is a two-state intersymbol-interference (ISI) channel with erasure noise, and it is the simplest example of an ISI channel with erasure noise. Then, we introduce a slight generalization of the EXIT area theorem and apply the MAP threshold bound for the joint decoder. Both the MAP and BP erasure thresholds are computed and compared with each other. The result quantities the loss due to iterative decoding Some open questions include the tightness of these bounds and the extensions to non-erasure channels.

Rather than functioning as an icon, Involuted Matter dissolves into the background of commercial construction, conceals difference at the envelope, and orchestrates a succession of alternate environments. Accepting the unifying neutrality of a larger framework this project articulates difference at the individual site. But unlike iconic projects, the real force of this thesis unfolds through the interior. Identity is formed not at the level of district, but is centered on the individual occupation of a specific place. The program for this project is a jimjilbang or Korean Bath House. The jimjilbang has the potential to become a new form of collective space not typical of the American metropolis. The bath house is simultaneously an intimate and egalitarian public venue and a private center for personal well being. Immersed in the same waters and ambient environments, clothed in matching jimjilbang attire, a plurality of classes, age groups, and social values congregate around a common program.

Taiwan is usually considered as a small open economy. Trade and exchange rate policies in Taiwan have substantially changed since 1990s.Not only has trade been liberalized, but exchange rates of the New Taiwan Dollar(NTD) were also allowed to fluctuate. This paper applies the Threshold Regression with Endogenous Threshold Variables(THRET) Model that puted forward Kourtellos, Stengos and Tan (2007) and combines the expectation-augmented Phillips curve with a threshold for the pass-through. The paper examines whether the short-run magnitude of the pass-through is affected by the business cycle. For that purpose, the important variable is tested as thresholds: output gap change. The results indicate that the short-run pass-through is higher when the the economy is booming, as well as the exchange rate depreciates above some threshold. And showed in this has conformed to the business cycle theory which Goldfajn and Werlang (2000) , Carneiro, Monteiro and Wu (2002) , Muinhos (2001) proposed.

The implication of credit rationing models states that the effect of monetary policy on output may be stronger when credit conditions are tight than when they are loose. Therefore, there may be a thresholde effect on the relation between real money supply and output. Existing empirical studies on testing threshold effects ignore the fact that the monetary policy and the credit conditions are endogenous, which are follow some optimal rules. Seeing that the past studies considering the endogenous monetary policy only cannot provide substantial evidence of the credit rationing theory, this article provides an extending test of threshold effects when monetary policy and the indicator of credit conditions are endogenous. Moreover, this study finds that the US aggregate data can still provide significant evidence of a threshold effect on the relation between money and output, comparing to the endogenous monetary policy partially considered.

A lot of relevant literature indicates that stock market returns for the non-linear because the stock market is volatility asymmetry. To explore the impact between the stock and macroeconomic variables, it is necessary to analyze by nonlinear model, otherwise they will be a model set of problems. I adopt a threshold autoregressive modle to analyze the relationship between the ETF return on the exchange rate and economic growth. In this study, the ETF return is the threshold variable. First, in order to rearrange the linear test regression (Arrang Regression) with the F-statistic testing whether the nonlinear effect of the grid search to find the residual sum of squares, determine the optimal threshold of backward and thresholds value. To identify the threshold, it is estimated a two-regime model analysis in positive and negative reward, the correlation between exchange rate and ETF returns Spillover effect to explain economic growth for the ETF returns and how it affects, then the data drawn into a grid map, find the number of possible structural transition point, and finally AIC formula to calculate the value of the two -regime with the three-regime model of AIC and the minimum value is the optimal model.