A study and experiment plan for digital mobile communication via satellite

The viability of mobile communications is examined within the context of a frequency division multiple access, single channel per carrier satellite system emphasizing digital techniques to serve a large population of users. The intent is to provide the mobile users with a grade of service consistant with the requirements for remote, rural (perhaps emergency) voice communications, but which approaches toll quality speech. A traffic model is derived on which to base the determination of the required maximum number of satellite channels to provide the anticipated level of service. Various voice digitalization and digital modulation schemes are reviewed along with a general link analysis of the mobile system. Demand assignment multiple access considerations and analysis tradeoffs are presented. Finally, a completed configuration is described

Characterizations of quasitrivial symmetric nondecreasing associative operations

We provide a description of the class of n-ary operations on an arbitrary chain that are quasitrivial, symmetric, nondecreasing, and associative. We also prove that associativity can be replaced with bisymmetry in the definition of this class. Finally we investigate the special situation where the chain is finite

Fetal heart rate and fetal heart rate variability in Lipizzaner broodmares

Monitoring fetal heart rate (FHR) and fetal heart rate variability (FHRV) helps to understand and evaluate normal and pathological conditions in the foal. The aim of this study was to establish normal heart rate reference values for the ongoing equine pregnancy and to perform a heart rate variability (HRV) time-domain analysis in Lipizzaner mares. Seventeen middle- and late-term (days 121–333) pregnant Lipizzaner mares were examined using fetomaternal electrocardiography (ECG). The mean FHR (P = 0.004) and the standard deviation of FHR (P = 0.012) significantly decreased during the pregnancy. FHR ± SD values decreased from 115 ± 35 to 79 ± 9 bpm between months 5 and 11. Our data showed that HRV in the foal decreased as the pregnancy progressed, which is in contrast with the findings of earlier equine studies. The standard deviation of normal-normal intervals (SDNN) was higher (70 ± 25 to 166 ± 108 msec) than described previously. The root mean square of successive differences (RMSSD) decreased from 105 ± 69 to 77 ± 37 msec between the 5th and 11th month of gestation. Using telemetric ECG equipment, we could detect equine fetal heartbeat on day 121 for the first time. In addition, the large differences observed in the HR values of four mare-fetus pairs in four consecutive months support the assumption that there might be ‘high-HR’ and ‘low-HR’ fetuses in horses. It can be concluded that the analysis of FHR and FHRV is a promising tool for the assessment of fetal well-being but the applicability of these parameters in the clinical setting and in studs requires further investigation

<i>In vivo</i> X-ray elemental imaging of single cell model organisms manipulated by laser-based optical tweezers

We report on a radically new elemental imaging approach for the analysis of biological model organisms and single cells in their natural, in vivo state. The methodology combines optical tweezers (OT) technology for non-contact, laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time. The main objective of this work is to establish a new method for in vivo elemental imaging in a two-dimensional (2D) projection mode in free-standing biological microorganisms or single cells, present in their aqueous environment. Using the model organism Scrippsiella trochoidea, a first proof of principle experiment at beamline ID13 of the European Synchrotron Radiation Facility (ESRF) demonstrates the feasibility of the OT XRF methodology, which is applied to study mixture toxicity of Cu-Ni and Cu-Zn as a result of elevated exposure. We expect that the new OT XRF methodology will significantly contribute to the new trend of investigating microorganisms at the cellular level with added in vivo capability

Concentration of apricot juice using complex membrane technology

In this study, pressed apricot (Prunus armeniaca L.) juice was concentrated using complex membrane technology with different module combinations: UF-RO-OD, UF-RO-MD, UF-NF-OD and UF-NF-MD. In case of the best combination a cross-flow polyethylene ultrafiltration membrane (UF) was applied for clarification, after which preconcentration was done using reverse osmosis (RO) with a polyamide membrane, and the final concentration was completed by osmotic distillation (OD) using a polypropylene module. The UF-RO-OD procedure resulted in a final concentrate with a 65-70 °Brix dry solid content and an excellent quality juice with high polyphenol content and high antioxidant capacity.Nanofiltration (NF) and membrane distillation (MD) were not proper economic solutions.The influence of certain operation parameters was examined experimentally. Temperatures of UF and RO were: 25, 30, and 35 °C, and of OD 25 °C. Recycle flow rates were: UF: 1, 1.5, and 2 m3 h−1; RO: 200, 400, and 600 l h−1; OD: 20, 30 and 40 l h−1. The flow rates in the module were expressed by the Reynolds number, as well. Based on preliminary experiments, the transmembrane pressures of UF and RO filtration were 4 bar and 50 bar, respectively. Each experimental run was performed three times. The following optimal operation parameters provided the lowest total cost: UF: 35 °C, 2 m3 h−1, 4 bar; RO: 35 °C, 600 l h−1, 50 bar; OD: 20, 30 and 40 l h−1; temperature 25 °C.In addition, experiments were performed for apricot juice concentration by evaporation, which technique is widely applied in the industry using vacuum and low temperature.For description the UF filtration, a dynamic model and regression by SPSS 14.0 statistics software were applied

Development of Agricultural Market and Trade Policies in the CEE Candidate Countries.

This synthesis report focuses on the evolution of agricultural market and trade policies in the Central and Eastern European (CEE) candidate countries in the period 1997 to 2001. The developments were crucially influenced by (OECD, 2000a): ⢠the situation in world agricultural markets; ⢠the overall macroeconomic development in the countries considered; ⢠the prospective EU accession; ⢠bringing domestic agricultural policy in line with the Uruguay Agreement on Agriculture (URAA). High 1997 agricultural prices on world commodity markets were followed by a marked depression in 1998. With the exemption of milk products this trend continued in 1999. Likewise the economic and financial crisis in Russia had a considerable impact on agricultural policies. It hit the regions´ exports resulting in a decline in industrial as well as agricultural output1. Thus, compared to the previous years most of the CEE candidate countries experienced a slow down or even negative rates of growth in their Gross Domestic Product (GDP) in 1998 and 1999. In addition those countries felt increased budgetary pressures. Agricultural market and trade policies largely reacted to these developments. Border protection was increased in many countries in 1998. This was combined in some cases with export subsidies, and ad hoc producer aids to mitigate the adverse effects. The prospect of EU accession also had an influence on the agricultural policy design in the region with many countries implementing EU-type policy instruments. Thus, the importance of per hectare and per head payments increased in the region, quota like measures were implemented in some countries and as part of this development Estonia introduced tariffs for agro-food imports. Finally, many countries also continued to adjust their policies to comply with their commitments agreed to in the World Trade Organisation (WTO). Despite these general tendencies there are also differences in the development of agricultural policies between the various CEE candidates. Chapter 2 therefore provides an overview of the changes of agricultural market and trade policies in each of the 10 accession countries. It addresses the policy issues market access (e.g. tariffs, special safeguard measures), export subsidies (value and quantities) and domestic support (intervention policies, direct payments, input subsidies, production quotas). Chapter 3 provides a brief assessment of recent policy developments in the region in the light of EU accession and WTO commitments. The development of prices and values, e.g. export subsidies, agricultural support expenditure, were presented in the background papers provided by the country experts in current prices in national currencies. In this synthesis report they are in addition converted in Euro. This firstly allows for a better comparison among the CEE candidate countries as well as between those countries and the EU. Some of the accession countries still suffer from high inflation and thus a strong depreciation of their currency. Thus secondly, the conversion to Euros allows the comparisons to be made in real terms.Industrial Organization, International Development, Productivity Analysis,