The Effect of the Distance from the Size Press to the First Drier on Sheet Properties

It is the purpose of this thesis to attempt to evaluate the effect of the distance from the size press to the first drier on penetration and sheet properties. At a constant machine speed, this has the same effect as varying the dwell time of the starch on the sheet. It has been found that an optimum distance or dwell time exists for strength properties, namely, breaking length and burst factor. The effect on air resistance and tear, however, is much greater than the effect on the above. Tear was found to increase 20% with dwell time. Air resistance experienced a four fold increase. The strength properties changed because of a difference in penetration. Penetration was deep with short dwell time and decreased with extreme dwell time

Statistical support for the ATL program

Statistical experimental designs are presented for various numbers of organisms and agar solutions pertinent to the experiment, ""colony growth in zero gravity''. Missions lasting 7 and 30 days are considered. For the designs listed, the statistical analysis of the observations obtained on the space shuttle are outlined

Nonlinear theory of shocked sound propagation in a nearly choked duct flow

The development of shocks in the sound field propagating through a nearly choked duct flow is analyzed by extending a quasi-one dimensional theory. The theory is applied to the case in which sound is introduced into the flow by an acoustic source located in the vicinity of a near-sonic throat. Analytical solutions for the field are obtained which illustrate the essential features of the nonlinear interaction between sound and flow. Numerical results are presented covering ranges of variation of source strength, throat Mach number, and frequency. It is found that the development of shocks leads to appreciable attenuation of acoustic power transmitted upstream through the near-sonic flow. It is possible, for example, that the power loss in the fundamental harmonic can be as much as 90% of that introduced at the source

Effects of high subsonic flow on sound propagation in a variable-area duct

The propagation of sound in a converging-diverging duct containing a quasi-one-dimensional steady flow with a high subsonic throat Mach number was studied. The behavior of linearized acoustic theory at the throat of the duct was shown to be singular. This singularity implies that linearized acoustic theory is invalid. The explicit singular behavior was determined and used to sketch the development (by the method of matched asymptotic expansions) of a nonlinear theory for sound propagation in a sonic throat region

System integration of a Telerobotic Demonstration System (TDS) testbed

The concept for and status of a telerobotic demonstration system testbed that integrates teleoperation and robotics is described. The components of the telerobotic system are described and the ongoing projects are discussed. The system can be divided into two sections: the autonomous subsystems, and the additional interface and support subsystems including teleoperations. The workings of each subsystem by itself and how the subsystems integrate into a complete system is discussed

Landscape context mediates the relationship between plant functional traits and decomposition

Aims: It has been well demonstrated that several interacting endogenous and exogenous factors influence decomposition. However, teasing apart the direct and indirect effects of these factors to predict decomposition patterns in heterogenous landscapes remains a key challenge. Methods: At 157 locations in a temperate forest, we measured decomposition of a standard substrate (filter paper) over two years, the landscape context in which decomposition took place, and the functional composition of the woody species that contributed leaf litter to the forest floor where litter bags were placed. We tested for direct and indirect effects of landscape context and direct effects of forest functional composition on decay using structural equation modelling. Results: We found that landscape context had direct effects on decay and indirect effects on decay via its influence on the functional composition of the surrounding forest. Forest functional composition also had direct effects on decay, but these effects decreased or disappeared completely over time. Moreover, community weighted mean trait values were better predictors of decay than functional dispersion of leaf traits, and leaf nitrogen content and carbon content were better predictors of decay than leaf dry matter content or leaf toughness. Conclusions: Our results highlight the importance of an integrative approach that examines the direct and indirect effects of multiple factors for understanding and predicting decomposition patterns across heterogenous landscapes

Shark Declines in the Mediterranean Sea

Summarizes a study of population and biomass trends of large sharks in the Mediterranean, and highlights the risk of some species becoming extinct as a result of unintended capture in fishing gear, targeted shark fishing, and human population pressure

The Effects of Government Maize Marketing Policies on Maize Market Prices in Kenya

The Government of Kenya pursues maize marketing policy objectives through the National Cereals and Produce Board (NCPB) which procures and sells maize at administratively determined prices, and stores maize as a contingency against future shortages. A private sector marketing channel competes with the NCPB and prices in this channel are set by supply and demand forces. This paper estimates the effects of NCPB activities on the historical path of private sector maize market prices in Kenya between 1989 and 2004. Results provide important insights into the historical effects of the NCPB, and will provide useful input into deliberations on the appropriate role for the NCPB in the future. It was not possible to use a fully structural econometric model to estimate the historical policy effects because of data limitations in Kenya, which are typical of many developing countries. Instead we use a reduced form vector autoregression model (VAR) and show how policy simulation results can be obtained from a fairly parsimonious VAR that can be estimated with sparse data and imposes only minimal identification restrictions. Results show that NCPB activities have stabilized maize market prices in Kenya, reduced price levels in the early 1990s, and raised price levels by roughly 20 percent between 1995 and 2004. Because roughly 60 percent of Kenya's rural households purchase maize while less than 30 percent sell maize, the government's maize marketing board operations have transferred income from urban consumers and most small rural households to maize selling farmers.Kenya, income transfers, maize policy, price stabilization, VAR, International Development, C22, O2, Q13, Q18,