Digital Up and Down Converter for High Performance VHF and UHF transceiver

The Digital Up and Down Converter (DUC/DDC) is a basic building part of the professional digital mobile transceiver. The paper presents DDC/DDS for dual mode professional VHF/UHF transceiver developed for railway radio. The transceiver complies ETSI standards for NFM and Digital Mobile Radio (DMR). The DUC/DDC is featured with the channel selectivity exceeding 70 dB and dynamic range more than 90 dB. The implementation of the other standards that use constant envelope modulation like small satellite UHF communication links is also possible

Public administration management and social services in Czech municipalities: Perceived attitudes of municipal officials with the potential application of the smart city principles

Increasing demand for social services connected to the demographic and other changes of the European society presents serious challenge for public policy makers and for the administrative levels most concerned with social services provision. In the Czech Republic this level is represented by municipalities whose attitudes towards the offer of social services in their territory, the providers and the cooperation in this field were surveyed in this paper. Municipal officials’ attitudes to social services differ significantly within the researched sample from a full satisfaction with the present situation in a municipality to a strong dissatisfaction. The paper uses the results of the survey proceed by means of the principal component analysis and cluster analysis to identify the attitudes of the municipal officials in the Zlín Region of the Czech Republic and to divide said municipalities into four groups with similar attitudes and issues for which common policy measures may be adopted after more detailed inquiries into their specific issues. Close monitoring, as provided by this paper, presents detailed basis for local policy makers and the further planning of social services network. © 2017, Academy of Economic Studies from Bucharest. All rights reserved

Stochastic optimization of laboratory test workflow at metallurgical testing centers

The objective of the paper is to present a way to shorten the time required to perform laboratory tests of materials in metallurgy. The paper finds a relation between the time to perform a test of materials and the number of technicians carrying out the test. The relation can be used to optimize the number of technicians. The approach is based on probability theory, as the amount of material to be tested is unknown in advance, and uses powerful modelling techniques involving the generalized estimating equations.Web of Science55478277

Ensuring the visibility and traceability of items through logistics chain of automotive industry based on AutoEPCNet Usage

Traceability in logistics is the capability of the participants to trace the products throughout the supply chain by means of either the product and/or container identifiers in a forward and/or backward direction. In today's competitive economic environment, traceability is a key concept related to all products and all types of supply chains. The goal of this paper is to describe development of application that enables to create and share information about the physical movement and status of products as they travel throughout the supply chain. The main purpose of this paper is to describe the development of RFID based track and trace system for ensuring the visibility and traceability of items in logistics chain especially in automotive industry. The proposed solution is based on EPCglobal Network Architecture

Problems of application of measurement system analysis (MSA) in metallurgical production

This paper lists the most fundamental problems related to the application of measurement system analysis (MSA) in metallurgical production and outlines ways of solving them. Based on the real measurements it was found, that the width of the confidence interval constructed for the value of combined gage repeatability and reproducibility (GRR) can be reduced (and thus the reliability of the GRR value can be increased) more by raising the number of trials than by increasing the number of samples. The basic assumption for the use of analysis of variance (constant variance and the occurrence of outliers) can be verified by using the proposed multiple box and whisker plot.Web of Science55353753

Changes in soil dissolved organic carbon affect reconstructed history and projected future trends in surface water acidification

Preindustrial (1850s) and future (2060) streamwater chemistry of an anthropogenically acidified small catchment was estimated using the MAGIC model for three different scenarios for dissolved organic carbon (DOC) concentrations and sources. The highest modeled pH = 5.7 for 1850s as well as for 2060 (pH = 4.4) was simulated given the assumption that streamwater DOC concentration was constant at the 1993 level. A scenario accounting for an increase of DOC as an inverse function of ionic strength (IS) of soilwater and streamwater resulted in much lower preindustrial (pH = 4.9) and future recovery to (pH = 4.1) if the stream riparian zone was assumed to be the only DOC source. If upland soilwater (where significant DOC increase was observed at −5 and −15 cm) was also included, DOC was partly neutralized within the soil and higher preindustrial pH = 5.3 and future pH = 4.2 were estimated. The observed DOC stream flux was 2–4 times higher than the potential carbon production of the riparian zone, implying that this is unlikely to be the sole DOC source. Modeling based on the assumption that stream DOC changes are solely attributable to changes in the riparian zone appears likely to underestimate preindustrial pH

The mechanisms of movement control and time estimation in cervical dystonia patients

Traditionally, the pathophysiology of cervical dystonia has been regarded mainly in relation to neurochemical abnormities in the basal ganglia. Recently, however, substantial evidence has emerged for cerebellar involvement. While the absence of neurological "cerebellar signs" in most dystonia patients may be considered at least provoking, there are more subtle indications of cerebellar dysfunction in complex, demanding tasks. Specifically, given the role of the cerebellum in the neural representation of time, in the millisecond range, dysfunction to this structure is considered to be of greater importance than dysfunction of the basal ganglia. In the current study, we investigated the performance of cervical dystonia patients on a computer task known to engage the cerebellum, namely, the interception of a moving target with changing parameters (speed, acceleration, and angle) with a simple response (pushing a button). The cervical dystonia patients achieved significantly worse results than a sample of healthy controls. Our results suggest that the cervical dystonia patients are impaired at integrating incoming visual information with motor responses during the prediction of upcoming actions, an impairment we interpret as evidence of cerebellar dysfunction

Long-Term Changes in Aluminum Fractions of Drainage Waters in Two Forest Catchments with Contrasting Lithology

Aluminum (Al) chemistry was studied in soils and waters of two catchments covered by spruce (Picea abies) monocultures in the Czech Republic that represent geochemical end-members of terrestrial and aquatic sensitivity to acidic deposition. The acid-sensitive Lysina catchment, underlain by granite, was compared to the acid-resistant Pluhův Bor catchment on serpentine. Organically-bound Al was the largest pool of reactive soil Al at both sites. Very high median total Al (Alt) concentrations (40 μmol L−1) and inorganic monomeric Al (Ali) concentrations (27 μmol L−1) were observed in acidic (pH 4.0) stream water at Lysina in the 1990s and these concentrations decreased to 32 μmol L−1 (Alt) and 13 μmol L−1 (Ali) in the 2000s. The potentially toxic Ali fraction decreased in response to long-term decreases in acidic deposition, but Ali remained the largest fraction. However, the organic monomeric (Alo) and particulate (Alp) fractions increased in the 2000s at Lysina. In contrast to Lysina, marked increases of Alt concentrations in circum-neutral waters at Pluhův Bor were observed in the 2000s in comparison with the 1990s. These increases were entirely due to the Alp fraction, which increased more than 3-fold in stream water and up to 8-fold in soil water in the A horizon. Increase of Alp coincided with dissolved organic carbon (DOC) increases. Acidification recovery may have increased the content of colloidal Al though the coagulation of monomeric Al

Characterization of mechanically alloyed FeAlSi intermetallic powders

Powder metallurgy is very promising material production technology which allows to prepare the alloys that could hardly be manufactured by other processing route. Basic prerequisite to obtain the product of desired properties is the high quality of initial primary commodities, i.e. powders in the case of powder metallurgy. One of the available methods of powder preparation is so called mechanical alloying which starts from blended powder mixtures and allows production of homogeneous materials by severe deformation in a high-energy ball charge. This technology is especially suitable for brittle materials such as intermetallic alloys being developed for high-temperature and corrosive environments applications [1]. Please click Additional Files below to see the full abstract