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Performance measurement techniques historical measurements

Measurements of production cross sections are performed with a wide range of both radiochemical and direct counter techniques. Historically, radiochemical techniques were particularly useful for measuring heavy residues, for which discrete Z and A identification are difficult to determine with nuclear particle detectors in reactions with normal kinematics. However, with the availability of very heavy-ion beams and the widespread use of reverse kinematics, the measurement of mass (dcr dA), charge (dcr dZ), and isotope (dheavy residues, these values are frequently summarized graphically in terms of an excitation function, or cross section as a function of projectile energy, as in O Fig. 3.11. Extensive listings of production cross sections are maintained in several databases (IAEA 2010 NEA 2010 NNDC 2010 RNDC 2003). [Pg.159]

Even for the large organization with significant annual hours worked, in addition to historical data, hazard-specific and qualitative performance measures (safety audits, perception surveys, the incident recall technique) are also necessary, particularly to identify low-probability/severe-consequence risks. [Pg.60]

Consider one small molecule, phenylalanine. It is an essential amino acid in our diet and is important in protein synthesis (a component of protein), as well as a precursor to tyrosine and neurotransmitters. Phenylalanine is one of several amino acids that are measured in a variety of clinical methods, which include immunoassay, fluorometry, high performance liquid chromatography (HPLC see Section 4.1.2) and most recently MS/MS (see Chapter 3). Historically, screening labs utilized immunoassays or fluorimetric analysis. Diagnostic metabolic labs used the amino acid analyzer, which was a form of HPLC. Most recently, the tandem mass spectrometer has been used extensively in screening labs to analyze amino acids or in diagnostic labs as a universal detector for GC and LC techniques. Why did MS/MS replace older technological systems The answer to this question lies in the power of mass spectrometer. [Pg.289]

Studies of atmospheric properties using IR spectroscopy techniques have been reported in the literature for nearly 100 years. This paper presents a brief historical review of the development of this area of science and discusses the common features of spectrographic instruments. Two state of the art instruments on opposite ends of the measurement spectrum are described. The first is a fast response iri situ sensor for the measurement of the exchange of CO2 between the atmosphere and the earth s surface. The second is a rocketborne field-widened spectrometer for upper atmosphere composition studies. The thesis is presented that most improvements in current measurement systems are due to painstakingly small performance enhancements of well understood system components. The source, optical and thermal control components that allow these sensors to expand the state of the art are detailed. Examples of their application to remote canopy photosynthesis measurement and upper atmosphere emission studies are presented. [Pg.217]

Abstract This chapter reviews the basic theory and applications of piezoelectric immunosensors. The immunosensor assay formats most often used are introduced as well as a brief explanation of the typical methods of measurement. Immobilisation is discussed, the importance of each characteristic, the basic techniques employed and a comparison of their performance as investigated by many researchers. The main historical developments of piezoelectric sensors and how these have led to early piezoelectric immunosensors are reviewed. Immunosensor applications and a comparison of sensor performance, for various analytes are summarised. The potential future of this field is also discussed. [Pg.237]

Section 14.2 presents a description of the TDL technique for temperature measurement, including the theory and basic principles behind the method. Section 14.3 provides a historical overview of the development of this technique to provide a sense of the considerable amount of research that has been performed in this field to date. Section 14.4 provides details of four TDL-based systems capable of temperature measurement in full-scale environments that are thought to be of particular interest to the industrial combustion community. Finally, Section 14.5 contains some concluding remarks about the current state of TDL sensors and possible outcomes of future developments. [Pg.312]

In modern chemical plants, thousands of measurements are recorded at frequencies that can exceed 1 Hz. Aside from plant operating conditions including pressures, temperatures, flow rates, and stream composition, other recorded variables include product purity, contamination levels (air, water, soil), and even safety compliance. All this information is stored in enormous databases. This historical record may be interrogated to monitor process performance, and control, for troubleshooting, to demonstrate environmental compliance and modeling. Often smoothing techniques are required to help identify trends in the data that may be masked by low signal-to-noise ratios. [Pg.74]

In the IAEA data analysis, various statistical techniques (IAEA 1998a) are used to derive separate estimates of the operator s and inspector s uncertainty parameters based on the collection of historical operator-inspector differences. The results of these evaluations are performance values, typical for a specific facility and for each stratum (material type) and measurement method combination. The actually observed verification measurement performance is then used for the planning (sample size calculations), the conduct (establishing reject limits), and the evaluation (material balance) of inspections in a given facility. [Pg.2904]

The purpose of this chapter is to present the LAD performance experiments carried out in room temperature liquids. Bubble point and reseal pressure tests for a 325x2300, 450 X 2750, and 510 x 3600 Dutch Twill screen are conducted in storable liquids, methanol, acetone, IPA, water, and binary methanol/water mixtures of various methanol concentrations. First screen pore diameters are estimated based on analysis from scanning electron microscopy and historical data. Experimental results are used to compare methods for determining effective pore diameter. Next, contact angles are measured for both pure and binary mixture fluids using a modified version of the Sessile Drop technique. Then, the equation of state analysis from Neumann and Good (1979) is used to determine the critical Zisman surface tension for stainless steel LAD screens, which... [Pg.87]


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