Time-stamping

Computer systems must provide time-stamped audit trails to record actions that create, modify, or delete electronic records. 

In postmarketing electronic longitudinal medical records, redundant and potentially contradictory information may come from several sources, (e.g., reports from medical residents, their supervisors, the attending physicians). In these cases time stamping of each event may help to delineate the important sequences in understanding the adverse events. 

Many investigations, confirmed by theoretical studies (Maher and Stevenson, 1988), indicate that the heavy bombardment of the primeval Earth about 3.8 billion years ago led to its sterilisation, so it was practically uninhabitable . The time stamp for the first stromatolith-forming prokaryotes, about 3.5 billion years ago (Schopf, 1993), does not in fact mark the beginning of the biogenesis process, but the appearance of quite complex life forms. Thus, the point at which the first primitive living systems appeared must have been considerably earlier. 

Monitored parameters are related to channels of a multi-channel counter. The number of counts found in the counter channels after each exposure will be reported in a monitor file 15 together with a time stamp. 

We have discussed individual analyses and the demands to achieve optimization of instrumentation. However, an analytical laboratory must deal with series of samples and we must consider another factor if we want to optimize complete workflows cycle time optimization. Cycle time is defined as the time from finishing the analysis of one sample to the time the next sample is finished. This can be easily determined on Microsoft Windows -based operating systems by examining the data file creation time stamps of two consecutive samples. A better way is calculating the average of a reasonable number of samples. 

To date, the WACHEM database contains 24,200 analyses made up of 323 separate analytical batches sourced from eleven laboratories. In order to maintain a dynamic database, the contents of available data are updated daily using a series of stored procedures, with each data download appropriately time stamped. 

In order to reflect these lead times, the concept of a timestamp is introduced. Timestamp is used in computer science documenting the system time when a certain event or transaction occurs e.g. for logging events (N.N. 2007). In the context of future inventory value planning, the time-stamp marks the period, when the first raw material has reached a certain stage in the value chain network included into a specific product. In the example illustrated in fig. 57, the raw material is processed in the same period to be converted into product 1. Therefore, all four value chain steps indexed from one to four occur in the same period and have the same time-stamp one. Conversion into product 2, however, requires additional time caused by production lead times, safety inventory and/or transportation time, that the steps indexed with five and six have a time stamp of two. The timestamp reflects that the inventory value of product 2 is not based on the raw material costs from the same period but based on the raw material costs from the previous period in order to reflect the lead time. Consequently, value chain indices and timestamps are defined for all steps and can cover multiple periods reflecting that raw materials in a global complex multi-stage value chain network can take several months, until they are sold as part of a finished product to the market. 

Section 11.10(d) Limiting system access to authorized individuals Section 11.10(e) Using secured, computer generated, time-stamped, audit trails... 

Databases date and time stamp all information. This makes accidental overwriting of raw data and methods impossible. 

A few days later, the infantry colonel s scoring of the military tasks arrived in the mail. He had been required to rate them blind, because there were deliberately no time stamps on them and Lloyd had re-recorded them in random sequence. Nevertheless, the colonel s judgment of military competence in each scene conformed closely to the corresponding NF score. The Edgewood cognitive tests once again proved to be good predictors of performance in the field. 

Paper subject diaries are notoriously poor in their legibility, completeness and accuracy. Electronic diaries are small, portable devices that can present text and graphics to the subject. They allow the subject to record and store responses, which can be time-stamped for each entry made. 

Written procedures and practices must be in place within the laboratory to verify the accuracy of manually entered and electronically transferred data collected on automated systems. The primary documentation for data entry requirements is an audit trail. Laboratories must ensure that an audit trail exists and is maintained. This audit trail must indicate date and time stamps for each record transmitted and the source instrument for each entry. 

Use of secure date and time stamp for the creation, modification, and deletion of data. 

User-independent computer-generated time-stamped audit trails. 

Fig. 15.9. Tracking usage of PGVL Hub. Each time a user logins into PGVL Hub, information about user ID and time stamp is recorded into a tracking database. A usage report can be generated via a Web reporting tool.

The use of time-stamped audit trails (Part 11.10(c) and (e)) to record changes, to record all write-to-file operations, and to independently record the date and time of any network system administrator actions or data entries/changes. 

Audit trails refer to a journal that records modifications to electronic records. The persons or automated processes operating on the user s behalf may perform these modifications. The audit-trail mechanism provides the capability to reconstruct the data prior to a modification, and therefore must not obscure the previously recorded data. The tracking mechanism must include a computer-generated time stamp that indicates the time of the entry. Audit trails are computer generated and can be part of the record that has been modified or a standalone record linked to the modified record. 

They must contain who did what, wrote what, and when (date and time stamp)... 

Analogous to a public notary, Digital Notary Services provide tmsted date-and-time stamp for a document, so that someone can later prove that the document existed at a point in time. May also verify the signature(s) on a signed document before applying the stamp. 

An audit trail is a journal recording any modifications carried out by the users, or by the processes operating on behalf of the user, to the electronic records. This mechanism provides the capability to reconstruct modified data and must not obscure the previously entered data. The tracking mechanism includes adding computer-generated date and time stamps to the record, to indicate when the record was modified, the types of modifications performed, and the identity of the person performing the modification to the record. 

All questions above can be answered and the problems can be handled reasonably, but not at a level of a common user and by simple means. Special institutions, trusted archives of electronically signed documents must be established. Since these must be trusted institutions, some rules and regulations for them must be worked out, like for certification authorities and time stamp authorities. 

Sending photons via open air requires identifying QKD photons from others such as coming from the sun. In the NIST system QKD photons are time stamped and looked for only when they are expected to arrive. 

The date and time stamp contained in this message conveys when CBER received your submission from the Electronic Submission Gateway. If your submission was received at CBER after 4 30 PM EST, the official receipt date for the submission is the next government business day. 

The scanner is designed to recognise coincidences where events occur in two opposing buckets within a resolving time of 12 ns. In normal operation, only coincidences between two elements in the same ring or adjacent rings (of the 8) were accepted, but for PEPT use this restriction was removed. The data acquisition system of the scanner was also modified so that coincidence data is recorded in list mode with time stamps at 1 ms intervals. 

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