Fiber Orientation as a Means to Control Formation on the Ultra-Former Through Changes in the Spouting Jet to Wire Speed Ratio and Stock Consistency in the Headbox

The Ultra-Former is a new type of multi-ply board machine. It uses a cylinder mold without a vat and has a stock delivery system that uses a headbox similar to that found on a fourdrinier machine. The board made on the Ultra-Former has several improved qualities over the board made on the conventional type board machines. Of these several improved qualities formation is one of the most important. Formation is important because it affects the physical properties of the finished product. One of the major physical properties affected is the tensile strength of the sheet. The tensile strength is reduced due to the higher probability of premature strain failure in areas of low fiber substance caused by poor formation. Formation is change through the adjustment of five key machine variables found on the fourdrinier type headbox. The spouting jet to wire speed ratio and the consistency in the headbox are the most important of the five variables and the easiest to control. This project involved the controlling of formation through fiber orientation as the most important variables, spouting jet to wire speed ratio and the consistency in the headbox are the most important of the five variables and the easiest to control. This project involved the controlling of formation through fiber orientation as the most important variables, spouting jet to wire speed ratio and consistency in the headbox, are changed. The fiber orientation is deplicted by using a ratio between the machine direction (MD) tensile and cross machine direction (CM) tensile as determined using the zero span tensile test. The results obtained indicate strongly that fiber orientation cannot be used for a formation control because the values are too random. At high degrees of fiber orientation the formation may be good one time and low at another time. Formation tended to be more dependent upon basis weight than fiber orientation

Growth kinetics of colloidal chains and labyrinths

Particles interacting by a combination of isotropic short-range attraction and long-range repulsion have been shown to form complex phases despite the apparent simplicity of the interparticle potential. Using computer simulations we study the behavior of two-dimensional systems of colloids with such an interaction, focusing on how area fraction and repulsion range at fixed repulsion gradient may be used to tune the resulting kinetics and nonequilibrium structure. While the short-range attraction leads to aggregation, the long-range repulsion encourages growth of chains of particles due to repulsive intercluster interactions. Depending on area fraction/ repulsion range we observe chain labyrinths, chain-compact aggregate coexistence, and connected networks of chains. The kinetics of cluster growth displays a sequence of connected networks and disconnected cluster or chain systems with increasing repulsion range, indicating the competing roles of connectivity of growing chains and repulsion-driven breakup of chains into compact aggregates. Chain-dominated systems show approximately logarithmic coarsening at late time that we interpret as the result of chains performing random walks in the randomly fluctuating potential landscape created by their neighbors, a situation reminiscent of glassy systems

Dynamic financial linkages among the Asia Pacific economies: an empirical assessment of real interest parity condition

Real Interest Parity (RIP) has been considered as the necessary rule to justify the exchange rates regime and the extent of financial integration among countries. This study of RIP condition is particularly important for the Asia Pacific economies that have undergone a series of currency crisis and financial turmoil. We incorporate three major analyses that cover the post liberalization period prior to the Asia financial crisis (1984-1997). First, we investigate the dynamic linkages of real interest rates among ASEAN-5 economies. Second, we assess the behavior of real interest differentials of Japan-ASEAN. Third, we examine the additional transmission channels of real interest rates from the US, Hong Kong, South Korea and Taiwan. Our findings suggest that there have been substantial integration among the ASEAN-5 and the East Asian with both the US and Japanese capital markets. However, the US-dominant hypothesis is more recognized. In addition, most countries are found vulnerable to external shocks and there is less monetary autonomy given that Asian economies have converged speedy to their equilibrium rates following the impulse from the US and the Japanese real interest rates. To great extent, our empirical evidence supports the recent proposal of common currency area as an alternative regime, not only to fight against systemic failures or monetary instability, but also to avoid the macroeconomic trilemma.Real interest parity, mean reversion, half-life, financial integration, common currency

International Parities among China and Her Major Trading Partners in Asia Pacific

As China’s role in world economy has steadily grown, her importance to the international trading and finance has also increased apace. A joint investigation of the international parity conditions for China and her thirteen major trading partners in Asia Pacific is thus conducted. Monthly observations and sub-samples within 1986-2007 are being considered to accentuate the effects of institutional changes and financial crisis. Advanced econometric procedures including the heterogeneous panel and endogenous break tests for unit root and correction factor model for half-life estimation are utilized in the analyses. Our findings reveal that first, endogenous and exponential breaks are confirmed for the real exchange and real interest differential series, which mostly occur in 1988, 1993/94 and 1997/98. Second, RIP holds better than PPP, suggesting the greater financial integration than trade integration among APEC-China. The undervalued exchange rate regime may exert some drawbacks against the PPP theorem. Third, both parities tend to hold better in the post-liberalization and post-crisis era, attributed not only to the financial liberalization process among APEC economies, but also to the Chinese trade policy and the regional commitment for the ASEAN+3+2+1 cooperation. Fourth, APEC members have has improved their ability to absorb external shocks as indicated by the shortened half-life reported overtime, especially when the post-crisis era is included.PPP, RIP, Non-linear Endogenous Breaks, Panel Unit Root Tests, Economic Integration

Arcjet Supplemental Diagnostics

This document proposes a new set of diagnostics designed to be implemented on the NASA Ames miniature Arcjet Research Chamber (mARC) for improved characterization of the flow. The diagnostics are grouped into three classes:higher cadence measurements, higher spatial resolution, and computer vision techniques for improved analysis of existing imaging. The goal is to better understand and quantify the following properties: flow statistics/uncertainty, temporal & spatial non-uniformity, flow temperature/enthalp

Bridging the gap between the Jaynes-Cummings and Rabi models using an intermediate rotating wave approximation

We present a novel approach called the intermediate rotating wave approximation (IRWA), which employs a time-averaging method to encapsulate the dynamics of light-matter interaction from strong to ultrastrong coupling regime. In contrast to the ordinary rotating wave approximation, this method addresses the co-rotating and counter-rotating terms separately to trace their physical consequences individually, and thus establishes the continuity between the Jaynes-Cummings model and the quantum Rabi model. We investigate IRWA in near resonance and large detuning cases. Our IRWA not only agrees well with both models in their respective coupling strengths, but also offers a good explanation for their differences

A dynamical systems model of unorganised segregation

We consider Schelling's bounded neighbourhood model (BNM) of unorganised segregation of two populations from the perspective of modern dynamical systems theory. We derive a Schelling dynamical system and carry out a complete quantitative analysis of the system for the case of a linear tolerance schedule in both populations. In doing so, we recover and generalise Schelling's qualitative results. For the case of unlimited population movement, we derive exact formulae for regions in parameter space where stable integrated population mixes can occur. We show how neighbourhood tipping can be adequately explained in terms of basins of attraction. For the case of limiting population movement, we derive exact criteria for the occurrence of new population mixes and identify the stable cases. We show how to apply our methodology to nonlinear tolerance schedules, illustrating our approach with numerical simulations. We associate each term in our Schelling dynamical system with a social meaning. In particular we show that the dynamics of one population in the presence of another can be summarised as follows {rate of population change} = {intrinsic popularity of neighbourhood} - {finite size of neighbourhood} - {presence of other population} By approaching the dynamics from this perspective, we have a complementary approach to that of the tolerance schedule.Comment: 17 pages (inc references), 9 figure

The effect of the run-up in the stock market on labor supply

This article presents estimates of the effect of the run-up in the stock market on labor supply. The authors find that, in the absence of a run-up in the stock market, aggregate labor force participation rates would have been about 1 percent higher than they are today.Labor supply ; Stock market

Low Band-Gap Donor Polymers for Organic Solar Cells

One of the key challenges of organic solar cells is their relatively low power conversion efficiency. One way to improve the efficiency of these cells is to develop donor materials with improved photon harvesting capabilities, well-located highest-occupied molecular orbital (HOMO) and lowest-unoccupied molecular orbital (LUMO) energy levels, good hole transport characteristics and good processability. In this thesis, the design, synthesis and characterization of fifteen low band gap donor-acceptor type polymers are described. Two different acceptor moieties, 3,6- bis(thien-2-yl)-2,5-di-N-alkylpyrrolo[3,4-c]pyrrole-1,4-dione (DPP) and 2,1,3- benzothiadiazole (BT) were used in our polymer designs and the polymers were synthesised using the palladium-catalysed Stille cross-coupling method. The first series of polymers were random co-polymers of DPP and dithienothiophene. By tuning the solubility and absorption characteristics of the polymers, we achieved a polymer that gave power conversion efficiencies of up to 4.85 % when applied in solar cells. Low open-circuit voltages were obtained for these cells, hence the next series of polymers was designed with the aim of improving the open-circuit voltages. Although the lower HOMO levels of these polymers resulted in higher open-circuit voltages when applied in solar cells, the low hole mobility of the polymers and poor morphology of the polymer:fullerene films resulted in low solar cell power conversion efficiencies. Finally, a series of benzothiadiazole-oligothiophene polymers were synthesised. These polymers had high hole mobilities and wide absorption spectra. When these polymers were applied in organic thin-film transistors, good hole mobilities of up to 0.20 cm2/Vs were achieved, and when applied in solar cells, power conversion efficiencies of up to 6.2 % were achieved. These results show that benzothiadiazoleoligothiophene systems are promising candidates for both transistor and solar cell applications