Channel Estimation Method for OFDM in Low SNR Based on Two-dimensional Spreading

In this paper, we present a channel estimation method based on two-dimensional signal spreading applicable to orthogonal frequency multiple access multicarrier systems. Our method exploits a spreading of a transmitted data signal as well as a pilot signal over the assigned frequency range and time period. As a spreading sequence we exploited orthogonal Walsh–Hadamard sequences. When compared with traditional pilot symbol based channel estimation, our method is beneficial in low signal to noise ratio (SNR). For a comparison of our method with state-of-the-art channel estimation method, we utilized an open source LTE downlink simulator developed at TU Vienna. This enables a reproducibility of our results. Considering the LTE system, our method outperforms the traditional approach in typical range of SNR from \(-\) 5 to 10 dB. For a comparison of a throughput performance, a number of channel models has been employed.     

Relation between blood hydrolases and small-intestinal contents

Absorption of enzymes in the small intestine and some mechanisms providing the enzymatic homeostasis in the body were studied in isolated portions of the small intestine of rats in chronic experiments on rats and dogs, and in clinically observed subjects. A conclusion has been made that under normal conditions the level of enzyme resorption is low, and it is localized in the distal portions of the small intestine. Changes in the hydrolytic activity of blood and urine are the result of not only the resorption of pancreatic enzymes from the small intestine, but also of the shifts in their incretion by the pancreas when enzymes are introduced into the duodenum, and the secretion of enzymes in the pancreatic juice is lowered, while their incretion by the pancreas into the blood flow is increased.     

The best screw shape for fine zinc oxide particles feeding

One of the most important requirements of particles feeding is a very homogeneous mass flow of fine particles. Screw feeders are among equipment used to feed particles in many industries. In this study, the performance of four single screw feeders with different pitch and blade shape screws has been studied experimentally for steady and stable feeding of fine zinc oxide particles at flow rates corresponding to laboratory scale range (under 10 g/min). The following results were obtained from this investigation: (I) the sticking problem of fine particles in angular pitch screw was solved by changing the pitch shape to circular; (II) the distribution of the fluctuations and their intensity in mass flow rates also lessen by using the circular pitch and a thin blade screw in place of the circular pitch and a thick blade screw. Also for both feeders, the feeding was often interrupted in low flow rates, but it will be disappeared by increasing the flow rate. Furthermore, the results of experiments show that the performance of the circular pitch and a thin blade screw feeder was better than other screw feeders and able to both swirl and mix the particles with different characteristics and reduce the mean aggregate size of the particle size distribution (PSD) when transmitting the zinc oxide particles.     

Identifying the unknowns by aligning fragmentation trees

Mass spectrometry allows sensitive, automated, and high-throughput analysis of small molecules. In principle, tandem mass spectrometry allows us to identify "unknown" small molecules not in any database, but the automated interpretation of such data is in its infancy. Fragmentation trees have recently been introduced for the automated analysis of the fragmentation patterns of small molecules. We present a method for the automated comparison of such fragmentation patterns, based on aligning the compounds' fragmentation trees. We cluster compounds based solely on their fragmentation patterns and show a good agreement with known compound classes. Fragmentation pattern similarities are strongly correlated with the chemical similarity of molecules. We present a tool for searching a database for compounds with fragmentation pattern similar to an unknown sample compound. We apply this tool to metabolites from Icelandic poppy. Our method allows fully automated computational identification of small molecules that cannot be found in any database.     

Leasing or buying white goods: comparing manufacturer profitability versus cost to consumer

Remanufacturing can create opportunities for companies to become more sustainable while remaining profitable. However, not all companies will be able to profit from moving towards a closed-loop business model. This paper investigates the profitability of leasing and remanufacturing washing machines for a large white goods producer based on data provided by them. A simple analytical model is built to simultaneously estimate the costs for consumers and costs and profits for the manufacturer under the leasing system. The results are compared with the costs and profitability of the linear system where premium, economy, and budget washing machines are sold to consumers. A sensitivity analysis is conducted on important factors such as repair, administration and transport costs. Using the replacement chain method, we show that the consumer costs of budget washing machines in the sales system is significantly higher than the costs for premium washing machines. Consequently, those consumers would benefit most from a circular system in which premium washing machines are leased against acceptable fees. However, the additional costs for the manufacturer make it a challenge to generate the same level of profit as in the linear system. The research discusses important cost components companies will have to address when making a move towards a circular business model with leasing and remanufacturing.     

Aging and source monitoring: Cognitive processes and neuropsychological correlates.

This study shows that relative to younger adults, older adults are more adversely influenced by similar items when judging a memory's source, and the phenomenal features of their correctly and incorrectly attributed memories have greater overlap. The authors argue in accordance with the source monitoring framework that this age-related impairment in source accuracy is related to processes involved in binding features into complex memories and those involved in accessing and evaluating contextual features of memories. These processes are linked to medial temporal and frontal brain regions, respectively, as evidenced by correlations in older adults between source accuracy and neuropsychological tests often used to assess medial temporal and frontal function. The results suggest that adequate feature binding is particularly important when items from different sources share similar features and access-evaluation processes are particularly important after a delay. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental illness and the impact of believing others know about it.

Reports 2 studies measuring the impact upon 30 male inpatients and 29 male outpatients of believing others have become aware of their psychiatric history. Ss thought the interest was in determining if another person would behave the same toward mental patients and controls. 1/2 the Ss were told the other person knew they were patients and the remainder that he believed them to be nonpatients. Believing others were aware of their status caused Ss to feel less appreciated, to find a task more difficult, and to perform more poorly, and they were perceived as more tense, anxious, and poorly adjusted by an O. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)