Computer Time Synchronization Computer Time Synchronization
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Measurement of Time
Measurement of Time M.Y. ANAND, B.A. KAGALI* Department of Physics, Bangalore University, Bangalore 560056 *email: [email protected] ABSTRACT Time was historically measured using the periodic motions of the sun and stars. Various types of sun clocks were devised in Egypt, Greece and Europe. Different types of water clocks were assembled with ever greater accuracy. Only in the seventeenth century did the mechanical clock with pendulums and springs appeared. Accurate quartz clocks and atomic clocks were developed in the first half of the twentieth century. Now we have clocks that have better than microsecond accuracy. This article gives a brief account of all these topics. Keywords: Sun clocks, Water clocks, Mechanical clocks, Quartz clocks, Atomic clocks, World Time, Indian Standard time We all know intuitively what time is. It can be civilizations relied upon the apparent motion of roughly equated with change or motions. From these bodies through the sky to determine the very beginning man has been interested in seasons, months, and years. understanding and measuring time. More We know little about the details of recently, he has been looking for ways to limit timekeeping in prehistoric eras, but we find the “damaging” effects of time and going that in every culture, some people were backward in time! preoccupied with measuring and recording the Celestial bodies—the Sun, Moon, planets, passage of time. Ice-age hunters in Europe over and stars—have provided us a reference for 20,000 years ago scratched lines and gouged measuring the passage of time. Ancient holes in sticks and bones, possibly counting the Physics Education • January − March 2007 277 days between phases of the moon. -
Grade 6 Quarter 1 Lessons Ycsd.Pdf
Name__________________________________________________________________ th 6 Grade - Grading Period 1 Overview Ohio's New Learning Standards Minerals have specific, quantifiable properties. (6.ESS.1) Igneous, Metamorphic, and Sedimentary rocks have unique characteristics that can be used for identification and/or classification. (6.ESS.2) Igneous, Metamorphic, and Sedimentary rocks form in different ways. (6.ESS.3) Clear Learning Targets "I can": 1. _____ follow a laboratory procedure and work collaboratively within a group using appropriate scientific tools. 2. _____ work individually, with a partner, and as a team to test a scientific concept, change a variable, and record the experimental outcome. 3. _____ use the engineering design cycle to develop a solution with a predictable outcome. 4. _____ cite specific text or online resource to support a proposed design solution. 5. ____ identify minerals by testing their properties 6. ____ use mineral properties, to use in testing and identifying minerals. 7. ____ use the rock cycle to describe the formation of igneous, sedimentary and metamorphic rocks. 8. ____ identify the unique characteristics to classify rocks. 9. ____ describe the formation of igneous, metamorphic, and sedimentary rocks 10. ____ use the unique characteristic of sedimentary rocks to identify and classify sedimentary rocks. 11. ____ identify the characteristics/classify metamorphic rocks. 12. ____ describe how metamorphic rocks form. Name_________________________________________________________________ th 6 Grade - Grading -
UA509: DCF77 Radio Clock DCF77 Radio Clock UA509 with 2 Serial Interfaces, Pulses Per Minute and Per Second, and a 2.5Mm LED Display
Meinberg Radio Clocks Auf der Landwehr 22 31812 Bad Pyrmont, Germany Phone: +49 (5281) 9309-0 Fax: +49 (5281) 9309-30 http://www.meinberg.de [email protected] UA509: DCF77 Radio Clock DCF77 Radio Clock UA509 with 2 serial interfaces, pulses per minute and per second, and a 2.5mm LED Display. Key Features - Direct conversion Quadrature Receiver - Pulses per second and per minute - 20mA input/output circuits - 2,5mm LED-display - 2 RS232 interfaces - Receiver status LEDs - Buffered hardware clock - Flash-EPROM with bootstrap loader rev 2006.0615.1425 Page 1/3 ua509 Description The hardware of UA509 is a 100mm x 160mm microprocessor board. The 20mm wide front panel contains an 8-digit LED display (2.5mm), three LED indicators and a time/date switch. The receiver is connected to the external ferrite antenna AI01 that is included in the sope of supply by the 5 meter 50 ohm coaxial cable (other lengths available). The radio controlled clock UA509 has been designed for applications where two independent serial interfaces are needed. The UA509 contains a flash EPROM with bootstrap loader that allows to upload a new firmware via the serial interface without removal of the clock. Characteristics Type of receiver Narrowband DCF77 quadrature receiver with automatic gain control, bandwidth: approx. 20Hz Display 8 digit 7-segment LED display (2.5mm) for time or date (switch-selectable) optional: 20HP (100mm) wide front panel with 10mm height 7-segment LED display Status info Modulation and field strength visualized by LEDs Free running state visualized by LED after switching to free running quartz clock mode Synchronization time 2-3 minutes after correct DCF77 signal reception Accuracy free run Accuracy of the quartz base after min. -
2201 24-Hour Room Temperature Controller REV13
s 2201 24-hour room temperature controller REV13.. Heating applications • Mains-independent, battery-operated room temperature controller featuring user-friendly operation, easy-to-read display and large numbers • Self-learning two-position controller with PID response (patented) • Operating mode selection: - Automatic mode with two heating phases - Automatic mode with one heating phase - Continuous comfort mode - Continuous energy saving mode - Frost protection • Automatic modes with time switch program • Heating zone control Use Room temperature control in: • Single-family and vacation homes. • Apartments and offices. • Individual rooms and professional office facilities. • Commercially used spaces. Control for the following equipment: • Magnetic valves of an instantaneous water heater. • Magnetic valves of an atmospheric gas burner. • Forced draught gas and oil burners. • Electrothermal actuators. • Circulating pumps in heating systems. • Electric direct heating. • Fans of electric storage heaters. • Zone valves (normally open and normally closed). CE1N2201en 24.04.2008 Building Technologies Function • PID control with self-learning or selectable switching cycle time • 2-point control • 24-hour time switch • Remote control • Preselected 24-hour operating modes • Override function • Party mode • Frost protection mode • Information level to check settings • Reset function • Sensor calibration • Minimum limitation of setpoint • Synchronization to radio time signal from Frankfurt, Germany (REV13DC) Type summary 24-hour room temperature controller REV13 24-hour room temperature controller with receiver for time signal from Frankfurt, Germany (DCF77) REV13DC Ordering Please indicate the type number as per the "Type summary" when ordering. Delivery The controller is supplied with batteries. Mechanical design Plastic casing with an easy-to-read display and large numbers, easily accessible operating elements, and removable base. -
Clock Synchronization Clock Synchronization Part 2, Chapter 5
Clock Synchronization Clock Synchronization Part 2, Chapter 5 Roger Wattenhofer ETH Zurich – Distributed Computing – www.disco.ethz.ch 5/1 5/2 Overview TexPoint fonts used in EMF. Motivation Read the TexPoint manual before you delete this box.: AAAA A • Logical Time (“happened-before”) • Motivation • Determine the order of events in a distributed system • Real World Clock Sources, Hardware and Applications • Synchronize resources • Clock Synchronization in Distributed Systems • Theory of Clock Synchronization • Physical Time • Protocol: PulseSync • Timestamp events (email, sensor data, file access times etc.) • Synchronize audio and video streams • Measure signal propagation delays (Localization) • Wireless (TDMA, duty cycling) • Digital control systems (ESP, airplane autopilot etc.) 5/3 5/4 Properties of Clock Synchronization Algorithms World Time (UTC) • External vs. internal synchronization • Atomic Clock – External sync: Nodes synchronize with an external clock source (UTC) – UTC: Coordinated Universal Time – Internal sync: Nodes synchronize to a common time – SI definition 1s := 9192631770 oscillation cycles of the caesium-133 atom – to a leader, to an averaged time, ... – Clocks excite these atoms to oscillate and count the cycles – Almost no drift (about 1s in 10 Million years) • One-shot vs. continuous synchronization – Getting smaller and more energy efficient! – Periodic synchronization required to compensate clock drift • Online vs. offline time information – Offline: Can reconstruct time of an event when needed • Global vs. -
18 TK Client DS
SECURE ENTERPRISE TIME SYNC WHITEPAPER SERIES TimeKeeper’s Competitive Survey Introduction The TimeKeeper® suite of products are more accurate, more reliable and far more capable than CAPEX-free open source alternatives. TimeKeeper has a lower OPEX than alternatives, but more importantly, TimeKeeper has features found nowhere else. These features include the ability to verify time is correct, compare against many time sources, report when time is incorrect or when time sources fail, and much more. Standard logging and integration provide guarantees of accuracy whenever proof is needed in the future. Some TimeKeeper customers previously built large in-house projects to try to make alternative solutions fit their needs. These expensive and very limited solutions were abandoned once they saw TimeKeeper gave them all they needed and more out of the box, saving valuable time and resources. TimeKeeper in use TimeKeeper hardware and software is in use by financial institutions of all sizes, from exchanges and very throughout Wall Street & large investment banks to small “prop shops”. TimeKeeper is there because after rigorously evaluating the globally product, customers found it gave them capabilities they simply could not get anywhere else. In addition, TimeKeeper support is far better than any of the competition. A few comments from our customers: “KCG has been using TimeKeeper Client and Server Software for two years in our trading environment with great success. TimeKeeper delivers accurate time, and has helped us to reduce operational risk with its built-in failover and event notification. We use TimeKeeper Client Software on our servers, using NTP or PTP to sync them to our GPS Based TimeKeeper Servers.” – Steve Newman, Managing Director, Corporate IT and Infrastructure, KCG “Technology is readily accessible for synchronizing to the microsecond, and there is no excuse for not having this in place today. -
2203 Weekday / Weekend Room Temperature Controller REV17
s 2203 Weekday / weekend room temperature controller REV17.. Heating applications • Mains-independent, battery-operated room temperature controller featuring user-friendly operation, easy-to-read display and large numbers • Self-learning two-position controller with PID response (patented) • Operating mode selection: - 7-day (weekday / weekend) automatic mode. with max. 3 heating phases - Continuous comfort mode - Continuous energy saving mode - Frost protection - Exception day (24 hour operation) with max. 3 heating phases • A separate temperature setpoint can be entered in automatic mode and for the exception day for each heating phase • To control a heating zone Use Room temperature control in: • Single-family and vacation homes • Apartments and offices • Individual rooms and professional office facilities • Commercially used spaces Control for the following equipment: • Magnetic valves of an instantaneous water heater • Magnetic valves of an atmospheric gas burner • Forced draught gas and oil burners • Electrothermal actuators • Circulating pumps in heating systems • Electric direct heating • Fans of electric storage heaters • Zone valves (normally open or normally closed) CE1N2203en 24.04.2008 Building Technologies Function • PID control with self-learning or selectable switching cycle time • 2-point control • 7-day time switch • Remote control • Preselected 24-hour operating modes • Override function • Holiday mode • Party mode • Frost protection mode • Information level to check settings • Reset function • Sensor calibration • Minimum limitation of setpoint • Periodic pump run Protection against valve seizure • Synchronization to radio time signal from Frankfurt, Germany (REV17DC) Type summary Room temperature controller with 7-day (weekday/weekend) time switch REV17 Room temperature controller with 7-day (weekday/weekend) time switch and receiver for time signal from Frankfurt, Germany (DCF77) REV17DC Ordering Please indicate the type number as per the "Type summary" when ordering. -
DS1284/DS1286 Watchdog Timekeepers Are
DS1284/DS1286 Watchdog Timekeepers www.maxim-ic.com GENERAL DESCRIPTION FEATURES The DS1284/DS1286 watchdog timekeepers are . Keeps Track of Hundredths of Seconds, self-contained real-time clocks, alarms, watchdog Seconds, Minutes, Hours, Days, Date of the timers, and interval timers in a 28-pin JEDEC DIP Month, Months, and Years; Valid Leap Year and encapsulated DIP package. The DS1286 Compensation Up to 2100 contains an embedded lithium energy source and a . Watchdog Timer Restarts an Out-of-Control quartz crystal, which eliminates the need for any Processor external circuitry. The DS1284 requires an external . Alarm Function Schedules Real-Time-Related quartz crystal and a VBAT source, which could be a Activities lithium battery. Data contained within 64 8-bit . Embedded Lithium Energy Cell Maintains registers can be read or written in the same manner Time, Watchdog, User RAM, and Alarm as byte-wide static RAM. Data is maintained in the Information watchdog timekeeper by intelligent control circuitry . Programmable Interrupts and Square-Wave that detects the status of VCC and write protects Outputs Maintain JEDEC Footprint memory when VCC is out of tolerance. The lithium . All Registers are Individually Addressable via energy source can maintain data and real time for the Address and Data Bus over 10 years in the absence of VCC. Watchdog . Accuracy is Better than ±1 Minute/Month at timekeeper information includes hundredths of +25°C (EDIP) seconds, seconds, minutes, hours, day, date, month, . Greater than 10 Years of Timekeeping in the and year. The date at the end of the month is Absence of VCC automatically adjusted for months with fewer than . -
DLC32 / DATAREG 32C Data Logger
DLC32 / DATAREG 32C Data logger User Manual Doc.-No: E122211209022 Baer Industrie-Elektronik GmbH Rathsbergstr. 23 D-90411 Nürnberg Phone: +49 (0)911 970590 Fax: +49 (0)911 9705950 Internet: www.baer-gmbh.com COPYRIGHT Copyright © 2009 BÄR Industrie-Elektronik GmbH All rights, including those originating from translation, (re)-printing and copying of this document or parts thereof are reserved. No part of this manual may be copied or distributed by electronic, mechanic, photographic or indeed any other means without prior written consent of BÄR Industrie-Elektronik GmbH. All names of products or companies contained in this document may be trademarks or trade names of their respective owners. Note Based on its policies, BÄR Industrie-Elektronik GmbH develops and improves their products on an ongoing basis. In consequence, BÄR Industrie-Elektronik GmbH preserve the right to modify and improve the software product described in this document. Specifications and other information contained in this document can change without prior notice. This document does not cover all functions in all possible detail or variations that may be encountered during installation, maintenance and usage of the software. Under no circumstances whatsoever will BÄR Industrie-Elektronik GmbH accept any liability for mistakes in this document or for any sub sequential damage arising from installation or usage of the software. BÄR Industrie-Elektronik GmbH preserves the right to modify or withdraw this document at any time without prior announcement. BÄR Industrie-Elektronik GmbH does not accept any responsibility or liability for the installation, usage, maintenance or support of third party products. Printed in Germany Table of Contents 1 General Information............................................................................................. -
A Measure of Change Brittany A
University of South Carolina Scholar Commons Theses and Dissertations Spring 2019 Time: A Measure of Change Brittany A. Gentry Follow this and additional works at: https://scholarcommons.sc.edu/etd Part of the Philosophy Commons Recommended Citation Gentry, B. A.(2019). Time: A Measure of Change. (Doctoral dissertation). Retrieved from https://scholarcommons.sc.edu/etd/5247 This Open Access Dissertation is brought to you by Scholar Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Time: A Measure of Change By Brittany A. Gentry Bachelor of Arts Houghton College, 2009 ________________________________________________ Submitted in Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Philosophy College of Arts and Sciences University of South Carolina 2019 Accepted by Michael Dickson, Major Professor Leah McClimans, Committee Member Thomas Burke, Committee Member Alexander Pruss, Committee Member Cheryl L. Addy, Vice Provost and Dean of the Graduate School ©Copyright by Brittany A. Gentry, 2019 All Rights Reserved ii Acknowledgements I would like to thank Michael Dickson, my dissertation advisor, for extensive comments on numerous drafts over the last several years and for his patience and encouragement throughout this process. I would also like to thank my other committee members, Leah McClimans, Thomas Burke, and Alexander Pruss, for their comments and recommendations along the way. Finally, I am grateful to fellow students and professors at the University of South Carolina, the audience at the International Society for the Philosophy of Time conference at Wake Forest University, NC, and anonymous reviewers for helpful comments on various drafts of portions of this dissertation. -
Table of Contents
TABLE OF CONTENTS SECTION I ACCESS THE KRONOS TIMEKEEPER I-1 SECTION II POST ABSENCE/ATTENDANCE CODES IN KRONOS II-1 A. Absence Reports II-1 B. Absence/Attendance Pay Codes II-2 C. Teacher’s Full Time Equivalency (FTE) II-8 D. Absences Posted to an Employee in the Full Screen Editor II-10 E. Employee's Balances Viewed from the Full Screen Editor II-19 F. Absences Viewed from the History Module II-21 SECTION III EDIT TIME IN TIME EDITOR III-1 A. Time Editor II-1 B. Editing a Punch or Absence Record III-4 C. Add an In and Out Punch III-6 D. Insert a Single Punch or a Transfer Punch III-9 E. Delete a Line Item III-11 F. Delete a Single Punch III-13 G. Forcing Overtime / Comp Time III-15 H. Editing Student Activities Records III-17 I Viewing Available Positions III-19 J. View Time Clock Punch Detail in History Inquiry III-21 Reference Pages Options in the Time Editor III-23 Function Keys in the Time Editor III-24 Help Screens Within the Column Headings III-25 SECTION IV RUN REPORTS FROM REPORT MODULE IV-1 A. Employee Master IV-2 B. Punch Detail IV-4 C. Punch Detail with Exceptions Only IV-8 D. Punch Detail Summary by Position Number IV-12 E. Punch Detail by Pay Codes IV-15 F Time Card Report IV-18 G. Total Hours IV-22 H. Approaching Overtime Report IV-24 I. Employee Accrual Report IV-26 Section II-1 Revised 7/23/2015 Revised SECTION V PRINT REPORTS FROM WORK SPOOL FILE V-1 A. -
Time and Frequency Users' Manual
,>'.)*• r>rJfl HKra mitt* >\ « i If I * I IT I . Ip I * .aference nbs Publi- cations / % ^m \ NBS TECHNICAL NOTE 695 U.S. DEPARTMENT OF COMMERCE/National Bureau of Standards Time and Frequency Users' Manual 100 .U5753 No. 695 1977 NATIONAL BUREAU OF STANDARDS 1 The National Bureau of Standards was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, a technical (3) basis for equity in trade, and (4) technical services to pro- mote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research the Institute for Applied Technology, the Institute for Computer Sciences and Technology, the Office for Information Programs, and the Office of Experimental Technology Incentives Program. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consist- ent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essen- tial services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry, and commerce. The Institute consists of the Office of Measurement Services, and the following center and divisions: Applied Mathematics