4,526 research outputs found
DMSK: A practical 2400-bps receiver for the mobile satellite service: An MSAT-X Report
The partical aspects of a 2400-bps differential detection minimum-shift-keying (DMSK) receiver are investigated. Fundamental issues relating to hardware precision, Doppler shift, fading, and frequency offset are examined, and it is concluded that the receiver's implementation at baseband is more advantageous both in cost and simplicity than its IF implementation. The DMSK receiver has been fabricated and tested under simulated mobile satellite environment conditions. The measured receiver performance in the presence of anomalies pertinent to the link is presented in this report. Furthermore, the receiver behavior in a band-limited channel (GMSK) is also investigated. The DMSK receiver performs substantially better than a coherent minimum-shift-keying (MSK) receiver in a heavily fading environment. The DMSK radio is simple and robust, and results in a lower error floor than its coherent counterpart. Moreover, this receiver is suitable for burst-type signals, and its recovery from deep fades is fast
A Concert Hall for Albuquerque, New Mexico
The problem is to design a cultural center in Albuquerque consisting of an art museum and a concert hall. The problem requires the establishment of a location and and site planning of the massing relationship between the concert hall and the museum. Then, the concert hall is to be extracted for extensive development in design
The gutâkidneyâheart axis in chronic kidney disease
The recent explosion of scientific interest in the gut microbiota has dramatically advanced our understanding of the complex pathophysiological interactions between the gut and multiple organs in health and disease. Emerging evidence has revealed that the gut microbiota is significantly altered in patients with chronic kidney disease (CKD), along with impaired intestinal barrier function. These alterations allow translocation of various gut-derived products into the systemic circulation, contributing to the development and progression of CKD and cardiovascular disease (CVD), partly mediated by chronic inflammation. Among potentially toxic gut-derived products identifiable in the systemic circulation, bacterial endotoxin and gut metabolites (e.g., p-cresyl sulfate and trimethylamine-N-oxide) have been extensively studied for their immunostimulatory and atherogenic properties. Recent studies have also suggested similar biological properties of bacterial DNA fragments circulating in the blood of patients with CKD, even in the absence of overt infections. Despite the accumulating evidence of the gut microbiota in CKD and its therapeutic potential for CVD, the precise mechanisms for multidirectional interactions between the gut, kidney, and heart remain poorly understood. This review aims to provide recent evidence on the associations between the gut microbiota, CKD, and CVD, and summarize current understanding of the potential pathophysiological mechanisms underlying the âgutâkidneyâheartâ axis in CKD
Hybrid ECAL: Optimization and Related Developments
Hybrid ECAL is a cost-conscious option of electromagnetic calorimeter (ECAL)
for particle flow calorimetry to be used in a detector of International Linear
Collider (ILC). It is a combination of silicon-tungsten ECAL, which realizes
high granularity and robust measurement of electromagnetic shower, and
scintillator-tungsten ECAL, which gives affordable cost with similar
performance to silicon. Optimization and a data acquisition trial in a test
bench for the hybrid ECAL are described in this article.Comment: 7 pages, 4 figures, Talk presented at the International Workshop on
Future Linear Colliders (LCWS14), Belgrade, Serbia, 6-10 October 201
High pressure X-ray preionized TEMA-CO2 laser
The construction of a high-pressure (up to 20 atm) transversely excited CO2 laser using transverse X-ray preionization is described. High pressure operation was found to be greatly improved in comparison to UV-preionized systems. Homogeneous discharges have been achieved in the pressure range 5â20 atm, yielding a specific laser output in the order of 35 J/l
Combined operations and the European theatre during the Nine Years' War, 1688-97
This is the author's PDF version of an article published in Historical research© 2005. The definitive version is available at www.blackwell-synergy.com.This article discusses the strategic and operational purpose of England's combined army-navy operations within the European theatre during the Nine Years' War, 1688-97. Specifically, the historical consensus that these operations were simply a compromise product of the contemporary political discourse, and consistently suffered from poor preparation and implementation, is reassessed. In so doing, the article considers the combined service descents planned and executed against the northern French coastline between 1691 and 1694, including in particular the renowned operation at Brest in June 1694, and also those operations undertaken by Admiral Russell's Mediterranean fleet in 1695.This article was submitted to the RAE2008 for the University of Chester - History
Coincidence between transcriptome analyses on different microarray platforms using a parametric framework
A parametric framework for the analysis of transcriptome data is demonstrated to yield coincident results when applied to data acquired using two different microarray platforms. Discrepancies among transcriptome studies are frequently reported, casting doubt on the reliability of collected data. The inconsistency among observations can be largely attributed to differences among the analytical frameworks employed for data analysis. The existing frameworks normalizes data against a standard determined from the data to be analyzed. In the present study, a parametric framework based on a strict model for normalization is applied to data acquired using an in-house printed chip and GeneChip. The framework is based on a common statistical characteristic of microarray data, and each data is normalized on the basis of a linear relationship with this model. In the proposed framework, the expressional changes observed and genes selected are coincident between platforms, achieving superior universality of data compared to other methods
An aerogel Cherenkov detector for multi-GeV photon detection with low sensitivity to neutrons
We describe a novel photon detector which operates under an intense flux of
neutrons. It is composed of lead-aerogel sandwich counter modules. Its salient
features are high photon detection efficiency and blindness to neutrons. As a
result of Monte Carlo (MC) simulations, the efficiency for photons with the
energy larger than 1 GeV is expected to be higher than 99.5% and that for 2
GeV/ neutrons less than 1%. The performance on the photon detection under
such a large flux of neutrons was measured for a part of the detector. It was
confirmed that the efficiency to photons with the energy 1 GeV was
consistent with the MC expectation within 8.2% uncertainty.Comment: 16 pages, 16 figures, submitted to Prog. Theor. Exp. Phy
Aerodynamic Forces Acting on Ahmed-Type Vehicles under Fluctuating Headwind Conditions
Aerodynamic forces of Ahmed-type road vehicles subjected to atmospheric fluctuation were studied in an advanced wind tunnel with programmable settings enabling the generation of pulsating wind speeds. The experiments were performed with a time-averaged airflow speed of approximately 13 m/s, with the fluctuating speed ranging from 2.58 to 2.90 m/s, and periods ranging from 1.5 to 5.0 s. The results of the time-dependent drag and lift forces acting on the vehicle were compared with those under steady wind conditions. Further, the influence of the rear slant angle of the Ahmed model on the forces was addressed. The fluctuation in wind speed showed a greater effect on the aerodynamic forces than predicted. The amplitude of the drag force under the pulsating wind became larger in a vehicle having a shape that experienced a large drag force under steady wind conditions. It is concluded that even under fluctuating wind conditions, there exists a critical angle of 30 at which the vehicle experiences either high or low fluid forces
Gas Absorption by Alkaline Solution in a Cyclone Scrubber: Experimental and Modeling Study
Experimental and modeling studies have been conducted on a CO2 absorption in a cyclone scrubber operated at room temperature. The effects of parameters such as the initial concentration of alkali in the solution and the liquid â gas ratio on the CO2 absorbed flux were experimentally and theoretically investigated. A theoretical study has been performed using a mathematical model based on the absorption in the liquid droplet with instantaneous reaction, in the inlet duct of the cyclone and in the cyclone itself. The results from the model were compared with experimental data and showed satisfactory agreement. Â Keywords: CO2 removal, mathematical model, wet cyclone scrubbe
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