Primary Level Measurements

Primary level measurements are made using different devices depending upon process conditions and the accuracy required. General types include  

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It is relevant to ask how often the routine measurement procedures currently used in laboratory medicine provide results that are traceable to high-level calibrators and reference measurement procedures (Lequin personal communication). It turns out that primary reference measurement procedures and primary calibrators are only available for about 30 types of quantity such as blood plasma concentration of bilirubins, cholesterols and sodium ion. International reference measurement procedures from the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and corresponding certified reference material from BCR are available for the catalytic activity concentration of a few enzymes such as alkaline phosphatase and creatine kinase in plasma. For another 25 types of quantity, such... 

It consists of three levels. At the top of the structure a network of national laboratories provides the primary chemical measurement standards and ensures that these are linked up with the international reference framework for chemical measurements. Via primary reference materials and reference measurements, a secondary level consisting of accredited chemical calibration laboratories, including verification authorities in the regulated area, is connected to the national standards level. 

A firm link must exist to the national institute, in metrology in chemistry to the national standards network, at the primary level via transfer standards (e.g. reference measurements and/or reference materials) or other means by which traceability to the national standards is ensured. 

The primary performance measures of a ligand-binding assay are bias/trueness and precision. These measures along with the total error are then used to derive and evaluate several other performance characteristics such as sensitivity (LLOQ), dynamic range, and dilutional linearity. Estimation of the primary performance measures (bias, precision, and total error) requires relevant data to be generated from a number of independent runs (also termed as experiments or assay s). Within each run, a number of concentration levels of the analyte of interest are tested with two or more replicates at each level. The primary performance measures are estimated independently at each level of the analyte concentration. This is carried out within the framework of the analysis of variance (ANOVA) model with the experimental runs included as a random effect [23]. Additional terms such as analyst, instmment, etc., may be included in this model depending on the design of the experiment. This ANOVA model allows us to estimate the overall mean of the calculated concentrations and the relevant variance components such as the within-run variance and the between-run variance. 

If the odors from male prairie voles play a primary role in mate selection by females, then males whose odors are preferred are expected to be chosen preferentially as mates. We tested our prediction using the 17 females from the odor-preference trials in which odors from control and food-deprived males were tested. These females were then observed and videotaped while in an enclosure with an unfamiliar pair of stimulus males (i.e., control and post-weaning food-deprived). The relative attractiveness of the odors from each male in a pair, and testosterone level, had previously been determined when each pair was used as scent-donors in an odor-preference test with another female. Because exposure to a female may affect male hormone levels, we determined the testosterone level of males the day after their use in a mate-preference test (A 61 d of age). There was no consistent pattern of change in testosterone level of males after exposure to a female, so we used the testosterone levels measured after the odor preference tests (51 d of age Figure 3) for analyses of female association and mate preferences. 

For prevention, improve the primary circuit information and particularly ultrasonic level measurement (with associated alarm and automatic actions). This increases operator information and control. 

The hot/cold intraface level in the upper density lock is determined by the total volume of the primary loop water mass, when the position of the interface level in the lower density lock is kept constant. The temperature measurements for the interface level in the upper lock are basically used for reactor pool volume control purposes. (The reactor primary loop volume control utilizes level measurements in the pressurizer.)... 

We shall further suppose that any type of measurement can be characterised, besides the proper measurement of flow or level, also by several other parameters. In addition, there must be defined also units of primary data measurement and functions for calculation of the balanced quantity on the basis of the flowmeter reading, pressure, temperature and the like. The type of measurement must also comprise information on measurement error, used in reconciliation of redundant data and detection of possible measurement gross errors. 

Within the PSLG Final Report, particular emphasis is given to overfill prevention as this is the primary means by which this major accident hazard can be prevented. In assessing what overfill prevention measures are required to reduce the risk to the environment to ALARP, the existing capacity of the bund and the tank level it was based on must be taken into account to determine the potential environmental consequences, eg whether the spillage is likely to be retained by the secondary containment system. If the overfill prevention system and the primary containment measures as a whole are in accordance with good practice, the risk to the environment is reduced. 

Primary quantity measured Local interactions (magnetic, electric field gradient) Atomic molecular potentials Energy levels Energy levels Energy levels... 

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