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composite indicators in order to provide rankings of institutions or countries. Among the different instruments of quality assessment in higher education, rankings probably get the most public attention. There clearly is a demand for ranking in the field of
Abstract
The analysis of airborne particulate matter (APM) by k 0-NAA was assessed using: (1) BCR reference material (RM) simulated air-filters, (2) synthetic air-filters prepared by spiking blank filters with standard solutions, and (3) real APM filters. k 0-INAA is a suitable technique for the analysis of APM, delivering accurate and precise results. However, the quality assessment of APM analysis appears to be a difficult task.
In the case of organic production the quality assessment of the fruits and vegetables is especially important. Monitoring of the maturation and ripening process, early detection of diseases, decision about harvest date and postharvest treatment need reliable, objective and – preferably – non-destructive quality testing methods. Dynamic hardness or stiffness measurement methods (resonance, impact, wave propagation) offer very useful tools in this field, but with strong limitations in applicability area and/or physical interpretation of the measured parameters. Our objective was to develop method and appropriate portable instrumentation to measure surface hardness – as quality measure – with a nondestructive method.
The computer controlled instrument has an electromagnetically excited impactor fitted with a piezoelectric acceleration sensor, a signal conditioner and A/D converter. To ensure the uniform contact behavior (contact area) between the impactor and the tested produce of wide range of shape, spherical head was applied. Conclusively, Hertz contact theory is to be applied for evaluation of the impact signal. Instead of using empirical “hardness index” – as in the case of several existing instruments – our objective was the physical interpretation of the contact phenomena. The measured acceleration signal was mathematically processed to calculate real physical parameters (force, speed, deformation), and to characterize the process similarly to the widely used texture analyzers, penetrometers. A new hardness parameter – “dynamic elastic modulus” – was introduced. According to the methodological investigations, the measurement was found to be perfectly non-destructive for a wide range of products. Conclusively, the developed method offers a useful tool for quality evaluation of organic horticultural products.
Abstract
It is generally accepted that an analytical procedure can be regarded as an information production system yielding information on the composition of the analyzed sample. Thus, information theory can be useful and the quantities characterizing the information properties of an analytical method may be applied not only as evaluation criteria but also as objective functions in the optimization. The usability of information theory is demonstrated on the example of neutron activation analysis. Both precision and bias of NAA results are taken into account together with the possible use of reference materials for quality assessment. The influence of the above-mentioned parameters on information properties such as information gain and profitability of NAA results is discussed in detail. It has been proved that information theory is especially useful in choosing suitable reference materials for the quality assessment of routine analytical procedures not only with respect to matrix and analyte concentration in the sample but also to concentrations and uncertainties of certified values in the CRM used. In the extreme trace analysis, CRMs with relatively large uncertainties and very low certified concentrations can still yield rather high information gain of results.
Abstract
The quality of commercial vegetable oils is usually evaluated via chemical parameters such as density, refractive index, saponification, iodine and acid values. In this paper, the applicability of thermal parameters for the quality assessment of vegetable oils is proposed. In order to achieve this goal, different back-propagation neural network architectures were trained, using chemical and thermal parameters as inputs. To avoid any accidental correlation due to the random initialization of the weights, each topology was repeated three times and three networks were chosen, with 5-3-2, 8-5-2 and 13-6-2 structures. The error function sum square error (SSE) was used as the criterion for finalization of the learning process. A model was developed for the correct classification of oils with regard to their type and quality.
One of the hottest topics of the international journals is the question: what is the effect of the public indicator-based quality assessment on the quality of care and on the decision of stakeholders, and which criteria should be applied for development of public quality assessment system. According to the international literature, the paper discusses 6 topics: (1) the ability of indicators to distinguish providers from the point of view of quality; (2) the appropriateness of outcome indicators to assess providers; (3) the ability of league tables to rank providers; (4) the people’s behaviour during choosing providers; (5) the impact of indicator-based public report; (6) recommendations for developing quality assessment system. Based on the literature review, the ability of indicators in distinguishing providers from the point of view of quality is doubtful primarily because of risk-adjustment problems. Other reasons are: the outcomes of care do not definitely refer to the quality of care process; the rankings of providers (league tables) based on more indicators are not reliable; people take into account mainly distance and the opinions of acquaintance when they choose providers; as a result of public reports the overall quality of care is declining. The publication of the results of measurement to assess providers has to be considered as a tool. For the purpose of helping people in choosing providers, the publication of patient satisfaction survey designed according to their preferences could achieve the desired effect. The quality improvement aims are definitely helped by the direct feedback to providers about the indicator values. Furthermore, a much finer picture can be made if the standardized audits of care and organisational processes are inserted into external assessment procedures.
. The technology of TCM chromatographic fingerprinting is playing a very important role in the quality assessment of TCM, and has proven to be scientific and comprehensive [ 7 ]. Lately, the chromatographic fingerprint technology has been
regression models and canonical correlation. Although several attempts have been made on the quality assessment of bread attributes in various wheat varieties, no comprehensive method has yet introduced to estimate the quality properties of bread from the raw
quality assessment of the raw material. Figure 1. Chromatogram of the fingerprints of the 11 samples 3.4 Relative Peak Area and Similarity
Compound danshen preparations (CDPs) are used clinically for the treatment of cardiovascular and cerebrovascular diseases. By using the quantitative analysis of multi-components by single-marker (QAMS) method, sixteen compounds (danshensu, protocatechuic acid, protocatechuicaldehyde, caffeic acid, rosmarinic acid, lithospermic acid, notoginsenoside R1, salvianolic acid B, ginsenoside Rg1, ginsenoside Re, salvianolic acid A, salvianolic acid C, ginsenoside Rb1, ginsenoside Rd, cryptotanshinone, and tanshinone IIA were quantified on an ACQUITY ultraperformance liquid chromatography (UPLC) HSS T3 column (2.1 × 100 mm, 1.8 μm) with the mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B) using a gradient elution at the flow rate of 0.30 mL/min in 30 min at 30°C, which was also validated by UPLC-diode array detection (DAD) and UPLC-electrospray ionization multistage/mass spectrometry (ESI-MS/MS) for assuring the feasibility and accuracy. Tested by robustness experiment under slightly changeable conditions, the stability of relative correction factor (RCF) proved to be stable, with RSDs below 5.69%, except for notoginsenoside R1 with relative standard deviation (RSD) 7.83%. This reliable and convenient QAMS method resolved the problem of standard substance insufficiency and improved the quality assessment of preparations consisting of complex compounds with different chemical structures, such as CDPs.
