System maintenance

The physical properties of plastic/polymer matrices and additives samples combined with the high GC column temperatures result in the mass spectrometer ion source becoming dirty more quickly than with typical usage. 

To limit instrument downtime, and if financially feasible, it is a good idea to have an extra ion source which can be exchanged after venting the instrument. This encourages more frequent source maintenance and provides more consistent analytical results. 

Crompton, T.R., Chemical Analysis of Additives in Plastics, 2nd Edition Pergamon Press, Oxford 1977. 

Freitag, W., Analysis of Additives in Plastics Additives, 4th Edition Edited by R. Gachter and H. Muller, Hanser Publishers, Munich 1993. 

Vandenburg, H.J. et al., Analytical Extraction of Additives from Polymers, Analyst, 1997, 122, 101R-115R. 

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A group of computers becomes a network when intercomputer communication is estabhshed. Prior to the 1980s, all system suppliers used proprietaiy protocols to network their systems. Ad hoc approaches were sometimes used to connect third-pai ty equipment, which was not cost-effective in system maintenance, upgrade, and expansion. The recent introduction of standardized protocols has led to a decrease in initial capital cost. Most current DCS network protocol designs are based on the ISO-OSI seven-laver model. 

DOD/USAF chlordane assessments NASA HVAC system maintenance... 

RISKMAN is an integrated Microsoft Windows , personal computer software system for [H. i forming quantitative risk analysis. Used for PSAs for aerospace, nuclear power, and chemical [iroccsses, it has five main modules Data Analysis, Systems Analysis, External Events Analysis, Event Tree Analysis, and Important Sequences. There are also modules for software system maintenance, backup, restoration, software updates, printer font, and page control. PEG has also integrated the fault tree programs CAFTA, SETS, NRCCUT, and IRRAS into RISKMAN. 

Residential Pricing Residential natural gas rates are for tiatural gas seivice atid for the gas commodity. The price of the gas commodity comprises about oue-third of the total price a residential customer pays, on average. The remainder of the bill includes amounts for transmission and distribution of gas, system maintenance, safety and inspection programs, customer service, metering, billing and other costs. 

The dominant reason for this ineffective management is the lack of factual data that quantifies the actual need for repair or maintenance of plant machinery, equipment and systems. Maintenance scheduling has been, and in many instances, is predicated on statistical trend data or on the actual failure of plant equipment. 

Finally, the control unit, apart from controlling voltage, has a magnetic polarity reversal switch operated by a variable timer, usually set to actuate every minute that cleverly ensures no scale can build up inside the unit, making the entire system maintenance free. ... 

LIMS as rented service— The application service provision provider (ASP) is a means of obtaining access to software applications without the need to acquire expensive licenses and hardware or employ high-cost support resources [7]. The application is hosted on a third-party site with system maintenance, backup, and recovery provided by a third party. Products and services can be rented for a contract period on a fixed cost per user/per month basis. The advantages of obtaining LIMS in this fashion include reduced cost in initial investment and reduced requirement of resources for maintaining the LIMS. The continued security and integrity of the data transferred over the Internet is a major concern for this type of LIMS. 

Unanticipated events that occur should be recorded in computer system maintenance records and include what corrective action was taken, who performed the corrective action, and when the action occurred. These events might include system crashes, date/time changes after a power failure, etc. 

A real discount rate of 10% was used to convert all future expenses and savings into current dollars. This allowed calculation of the net present value of the savings and costs. Also calculated were the discounted payback period and the simple payback period. Each of these quantities was calculated over a life cycle analysis period of 20 years, the assumed life of the mechanical system. Maintenance costs were considered to remain constant in real terms. 

Specific guidelines for laboratory information systems include regulahons for computer conhgurahon, procedure manuals, system security, data entry/reports/ retrieval, hardware and software, and system maintenance. 

Built-in diagnostics capabihties, such as a run log for status information and modular pneumatic manifolds, inlets and detectors, reduce system maintenance and improve uptime. 

Redundant dispense engines. Redundant dispense engines have become fairly common in both pump- and non-pump-based slurry dispense systems. Since slurry is both chemically and mechanically aggressive, a backup dispense engine enables system maintenance without interruption of supply to the fab. 

One of the manufacturing challenges with a full-system cleanout, is the need to interrupt manufacturing. Some fabs have installed totally redundant delivery systems, including dispense module and piping. Some adopt a scheduled downtime for system maintenance. Most simply refuse to recognize the need until disaster strikes in the form of unscheduled interruption of slurry delivery or dramatic increase in wafer defects. 

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