The Experts below are selected from a list of 726 Experts worldwide ranked by ideXlab platform
David L. Mills - One of the best experts on this subject based on the ideXlab platform.
-
computer network time synchronization the network time protocol
2006Co-Authors: David L. MillsAbstract:BASIC CONCEPTS Time Synchronization Time Synchronization Protocols Computer Clocks Processing Time Values Correctness and Accuracy Expectations Security NTP in the Internet Parting Shots References HOW NTP WORKS General Infrastructure Requirements How NTP Represents the Time How NTP Reckons the Time How NTP Disciplines the Time How NTP Clients and Servers Associate How NTP Discovers Servers How NTP Manages Network Resources How NTP Avoids Errors How NTP Performance Is Determined How NTP Controls Access How NTP Watches for Terrorists How NTP Clocks Are Watched Parting Shots References Further Reading IN THE BELLY OF THE BEAST Related Technology Terms and Notation Process Flow Packet Processing Clock Filter Algorithm Selection Algorithm Clustering Algorithm Combining Algorithm Huff-'n-Puff Filter Mitigation Rules and the Prefer Peer Poll Process Parting Shots References Further Reading CLOCK DISCIPLINE ALGORITHM Feedback Control Systems Phase and Frequency Discipline Weight Factors Poll Interval Control Popcorn and Step Control Clock State Machine Parting Shots References Further Reading NTP SUBNET CONFIGURATION Automatic Server Discovery Manual Server Discovery and Configuration Evaluating the Sources Selecting the Stratum Selecting the Number of Configured Servers Engineering Campus and Corporate Networks Engineering Home Office and Small Business Networks Hardware and Network Considerations Parting Shots References Further Reading NTP PERFORMANCE IN THE INTERNET Performance Measurement Tools System Clock Latency Characteristics Characteristics of a Primary Server and Reference Clock Characteristics between Primary Servers on the Internet Characteristics of a Client and a Primary Server on a Fast Ethernet Results from an Internet Survey Server and Network Resource Requirements Parting Shots References PRIMARY SERVERS AND REFERENCE CLOCKS Driver Structure and Interface Reference Clock Drivers Further Reading KERNEL TIMEKEEPING SUPPORT System Clock Reading Algorithm Clock Discipline Algorithms Kernel PLL/FLL Discipline Kernel PPS Discipline Clock Adjust Algorithm Proof of Performance Kernel PLL/FLL Discipline Performance Kernel PPS Discipline Parting Shots References Further Reading CRYPTOGRAPHIC AUTHENTICATION NTP Security Model NTP Secure Groups Autokey Security Protocol Parting Shots References Further Reading IDENTITY SCHEMES X509 Certificates Private Certificate (PC) Identity Scheme Trusted Certificate (TC) Identity Scheme Schnorr (IFF) Identity Scheme Guillou-Quisquater (GQ) Identity Scheme Mu-Varadharajan (MV) Identity Scheme Parting Shots References Further Reading ANALYSIS OF ERRORS Clock Reading Errors Timestamp Errors Sawtooth Errors Maximum Error Budget Expected Error Budget Parting Shots References MODELING AND ANALYSIS OF COMPUTER CLOCKS Computer Clock Concepts Mathematical Model of the Generic Feedback Loop Synthetic Timescales and Clock Wranglers Parting Shots References Further Reading METROLOGY AND CHRONOMETRY OF THE NTP TIMESCALE Scientific Timescales Based on Astronomy and Atomic Physics Civil Timescales Based on Earth Rotation How NTP Reckons with UTC Leap Seconds On Numbering the Calendars and Days On the Julian Day Number System On Timescales, Leap Events, and the Age of Eras The NTP Era and Buddy Epoch Comparison with Other Computer Timescales Primary Frequency and Time Standards Time and Frequency Dissemination Parting Shots References Further Reading NTP REFERENCE IMPLEMENTATION NTP Packet Header Control Flow Main Program and Common Routines Peer Process System Process Clock Discipline Process Clock Adjust Process Poll Process Parting Shots Reference Further Reading TECHNICAL HISTORY OF NTP On the Antiquity of NTP On the Proliferation of NTP around the Globe Autonomous Authentication Autonomous Configuration Radios, We Have Radios Hunting the Nanoseconds Experimental Studies Theory and Algorithms Growing Pains As Time Goes By Parting Shots References Further Reading BIBLIOGRAPHY INDEX
Jamie Seymour - One of the best experts on this subject based on the ideXlab platform.
-
Percent frequency of Chironex fleckeri medusae that metamorphosed each Day.
2013Co-Authors: Matthew Gordon, Jamie SeymourAbstract:Frequency is percentage within a sample and date is Julian Day Number or month, with 30 August referenced by a grey dash line. The first sampling occasion within a season is denoated by a grey arrowhead line, while subsequent sampling occasion(s) are denoted by a black arrowhead line.
Matthew Gordon - One of the best experts on this subject based on the ideXlab platform.
-
Percent frequency of Chironex fleckeri medusae that metamorphosed each Day.
2013Co-Authors: Matthew Gordon, Jamie SeymourAbstract:Frequency is percentage within a sample and date is Julian Day Number or month, with 30 August referenced by a grey dash line. The first sampling occasion within a season is denoated by a grey arrowhead line, while subsequent sampling occasion(s) are denoted by a black arrowhead line.
Holmsten Anton - One of the best experts on this subject based on the ideXlab platform.
-
Abiotiska faktorers inverkan på laxens (Salmo salar) dagliga lekvandring i två älvar i norra Sverige
SLU Dept. of Wildlife Fish and Environmental Studies, 2015Co-Authors: Holmsten AntonAbstract:Atlantic salmon (Salmo salar) depends on two major migrations to fulfil their life cycle, from their birth place in rivers to sea, and back upstream the river again to spawn. Salmon stocks have been heavily reduced during the last century due to human activities such as hydropower and timber floating. Construction of fish ladders and restoration of rivers are recent management actions taken aiming at improving the remaining salmon stocks. Salmon are monitored during their migrations to get information on the stock status. This study focused on how environmental factors correlated with adult salmon upstream spawning migration data from two rivers in northern Sweden, Västerbotten County, Umeälven and Byskeälven. Salmon data from both rivers were obtained from fish counters placed in fish ladders. The fish ladder in river Umeälven was equipped with two VAKI fish counters, and salmon data from 2010-2013 was used. Salmon data from 2009-2013 from river Byskeälven were used, the fish ladder was equipped with a PORO fish counter 2009-2012, and a VAKI fish counter 2013. There were three questions that led the study; (I) which environmental variables can explain the daily variations in salmon upstream migration? (II) Are there any major differences between the factors influencing salmon spawning migration in an exploited river compared to an unexploited river? (III) Can an environmental factor be of greater or less importance for salmon upstream migration during the first and the last half of the season? Stepwise linear regressions were used to create models to find how the environmental factors correlated with salmon upstream migration. Both rivers had a seasonal migration pattern with most of the salmon migrating early in the season. Water flow had most influence on the salmon upstream migration in the studied rivers. There was a difference in which environmental factors had most influence on salmon migration between the first and second 50 % of migrating salmon in river Byskeälven. Adjusted Julian Day Number explained most of the migration in the best model for the migration first half of the season. Water temperature, water flow, and adjusted Julian Day Number explained the migration in the second half of the season
