Search results for " synchronization"
showing 10 items of 75 documents
A Phase-Locked Loop for the Synchronization of Power Quality Instruments in the Presence of Stationary and Transient Disturbances
2007
Power quality instrumentation requires accurate fundamental frequency estimation and signal synchronization, even in the presence of both stationary and transient disturbances. In this paper, the authors present a synchronization technique for power quality instruments based on a single-phase software phase-locked loop (PLL), which is able to perform the synchronization, even in the presence of such disturbances. Moreover, PLL is able to detect the occurrence of a transient disturbance. To evaluate if and how the synchronization technique is adversely affected by the application of stationary and transient disturbing influences, appropriate testing conditions have been developed, taking int…
Decentralized Synchronization for Zigbee wireless sensor networks in Multi-Hop Topology
2010
Abstract The most effective solution for energy saving in low-rate wireless sensor networks is maintaining each node in a doze state as long as possible. In order to guarantee network connectivity, the intervals at which the network sensors are turned on and off have to be coordinated. We analyze the Zigbee MAC performance in sensor networks deployed in multi-hop topologies. For this networks, critical inefficiencies can arise due to transmissions performed by hidden nodes. We evaluate the impact of different synchronization schemes on the network performance, both in terms of network capacity and in terms of energy consumption. We show how the synchronization function can be opportunistica…
Synchronization protocols in Spanish Merino sheep Reduction in time to estrus by the addition of eCG to a progesterone-based estrus synchronization p…
2015
Abstract An appropriate management of reproduction allows ewes to breed at a more intensive rhythm, more compatible with economic efficiency of farms. Hence, the objectives of the present work were to evaluate a traditional estrus synchronization protocol (based on medroxyprogesterone acetate-impregnated intravaginal sponges combined or not with equine chorionic gonadotropin) on a Merino sheep herd during the breeding season, in order to determine the best working protocol for this breed. A total of 277 sheep, blocked by age (200 ewes and 77 ewe lambs) were randomly allocated to four groups, two of ewes (E and Ee) and two of ewe lambs (L and Le). All females received 60 mg MAP (medroxyproge…
Nanoseconds Timing System Based on IEEE 1588 FPGA Implementation
2019
Clock synchronization procedures are mandatory in most physical experiments where event fragments are readout by spatially dislocated sensors and must be glued together to reconstruct key parameters (e.g. energy, interaction vertex etc.) of the process under investigation. These distributed data readout topologies rely on an accurate time information available at the frontend, where raw data are acquired and tagged with a precise timestamp prior to data buffering and central data collecting. This makes the network complexity and latency, between frontend and backend electronics, negligible within upper bounds imposed by the frontend data buffer capability. The proposed research work describ…
Endocrine and ovarian response after a 2-day controlled suckling and eCG treatment in lactating rabbit does.
2006
Synchronization methods are used to obtain higher fertility when artificial insemination (AI) is applied to lactating rabbit does. The most common methods are eCG administration or temporary doe–litter separation. Nevertheless, drawbacks have been reported, such as negative side effects of hormonal treatment in the doe and low litter growth due to absence of suckling, respectively. Recently, improved reproductive performance (without visible consequences on young rabbit growth), has been obtained by applying a 2-day controlled nursing method before AI, by allowing for a 10 min nursing of the litter 24 h of separation. The present study was undertaken to examine the pituitary (PRL, LH, FSH) …
High resolution analysis and differential condensation in RBA-banded human chromosomes.
1981
Human prophase, premetaphase, and mid-metaphase chromosomes are prepared and analyzed using the thymidine cell synchronization technique and R-banding patterns (RBA). Haploid sets with 700–1000 bands can be demonstrated. Sequences of chromosomes of different degrees of condensation are helpful for a better understanding and classification of regions of extended chromosomes. A considerable variation in the condensation of parts of homologous chromosomes is reflected in the variability of the arm ratio. This differential condensation of chromosomes is entirely effected by variation of the degree of condensation in AT rich interbands and can be attributed to the degree of labeling by BrdU.
Time synchronization enhancements in wireless networks with ultra wide band communications
2022
The emergence of low cost Ultra Wide Band (UWB) transceivers has enabled the implementation of Wireless Sensor Networks (WSN) based on this communication technology. These networks are composed of distributed autonomous low cost nodes (also known as motes) with their own processing unit, memory and communications. Usually these nodes are power-limited and due to the poor performance and quality of their clocks, time synchronization is in the order of milliseconds and in some specific scenarios till microseconds. The integration of commercial UWB transceivers in these nodes can improve the synchronization accuracy. In particular, we focus on WSN nodes based on off-the-shelf commercial produc…
Effects of post-filtering in grid-synchronization algorithms under grid faults
2018
Abstract The spread of distributed generation systems has reinforced concerns and requirements on grid-tied power converters. The synchronization with the utility voltage vector is a major concern. In the literature, algorithms based on Phase Locked Loops are extensively presented. In spite of adequate performances under ideal and balanced grid conditions, under grid faults great inaccuracies arise. Shortcomings are overcome by advanced algorithms at the expenses of the complexity and computational cost. In this paper, grid synchronization algorithms are addressed. A solution is proposed by introducing a new post-filter stage in a Decoupled Double Synchronous Reference Frame not affecting, …
Liquidity Synchronization, Its Determinants and Outcomes under Economic Growth Volatility: Evidence from Emerging Asian Economies
2021
This study investigates the country-level determinants of liquidity synchronization and degrees of liquidity synchronization during economic growth volatility. As a non-diversifiable risk factor, liquidity co-movement shock spreads market-wide and thus disrupts the overall functioning of the financial market. Firms in Asian markets operate in legal and regulatory environments distinct from those of firms analyzed in the previous literature. Comprehensive analyses of liquidity synchronicity in emerging markets are limited. A major knowledge gap pertaining to Asian emerging markets serves as the primary motivation for this study. Seven Asian emerging economies are selected from the MSCI emerg…
Distributed GNSS-Based Time Synchronization and Applications
2016
The paper deals with synchronization standards, applications and challenges in the modern packet switched telecommunication networks. In recent years, the number of time-dependent services and systems only increases with the development of such areas as Internet of Things (IoT), industrial Internet, remote automation and robotics, precise positioning etc. In the paper, these emerging applications are discussed. An alternative way to the traditional centralized synchronization infrastructure is proposed. Compact and low-priced devices equipped with a Global Navigation Satellite System (GNSS) receiver and a reliable internal clock can be installed specifically in the places where they are nee…