Small-Molecule Pharmaceutical Impurities Test Method Validation: Precision Acceptance Criterion

2019 ◽  
pp. 397-414
Author(s):  
Russell L. Hertzler ◽  
Mark D. Johnson ◽  
Teodora Moldovan ◽  
Michael D. Oberlander ◽  
James Reynolds ◽  
...  
1998 ◽  
Vol 61 (11) ◽  
pp. 1579-1582 ◽  
Author(s):  
ROY P. BETTS ◽  
IRENE M. F. RENTENAAR

In recent years, food microbiologists have seen the development of a range of nonstandard methods designed to enumerate or determine the presence of various microorganisms in food products. Generally the new methods are designed to give the microbiologist advantages, such as greater automation or faster results, over standard conventional methods. The new methods, however, have often not been thoroughly tested to give the end user confidence in the results. In order to generate data to show that new methods give results that are comparable with standard methods, they must be validated. A number of validation schemes have been developed in various countries throughout the world. There has not, however, been an acceptable scheme recognized throughout Europe. The MicroVal project has been involved in the development of a European microbiological method validation and certification scheme; it involves 21 partners from 7 EU member States. New methods that are tested by the MicroVal system will undergo initial testing in a single expert laboratory, to establish the test's specificity, limit of detection, relative accuracy, sensitivity, and linearity. This testing will be followed by a collaborative study in a minimum of eight laboratories, which will be used to determine the test precision, repeatability, and reproducibility. All results will be assessed by two expert reviewers who will recommend or reject the test. Tests that are recommended will be finally accepted by a MicroVal committee. The committee will pass its comments to one of several certification bodies (working together through a memorandum of understanding) who will certify that the new method gives results that are equivalent to the reference method used throughout the validation work. The technical rules that describe the work required to certify a method are currently being considered by the European Committee for Standardization (CEN), with the objective that the rules will become a CEN standard for the certification of new test methods. When this objective has been achieved the rules will become an International Standards Organization (ISO) standard for new test method validation.


1999 ◽  
Vol 121 (3) ◽  
pp. 311-314
Author(s):  
G. S. Bhuyan ◽  
M. D. Rana

Leak as well as rupture types of failures related to sustained-load-cracking (SLC) have been observed in high-pressure gas cylinders fabricated from certain aluminium alloy. The stable crack growth mechanism observed primarily in the cylinder neck and shoulder area have been identified as the SLC mechanism occurring at room temperature without any environmental effect. The International Organization for Standardization (ISO) Sub-Committee 3, Working Group 16 has developed a test method to measure the SLC resistance using fracture mechanics specimens along with an acceptance criterion for aluminium cylinders. The technical rationale for the proposed test method and the physical significance of the acceptance criterion to the cylinder performance in terms of critical stress-crack size relationship is presented. Application of the developed test method for characterizing new aluminium alloy for manufacturing cylinders is demonstrated. SLC characteristics of several aluminium cylinders as well as on-board cylinders for natural gas vehicles assessed by the authors are discussed.


2000 ◽  
Vol 123 (3) ◽  
pp. 332-337 ◽  
Author(s):  
Mahendra D. Rana ◽  
W. D. Doty ◽  
Sumio Yukawa ◽  
Robert Zawierucha

Earlier research work conducted at MIT and NIST indicated that CVN specimens with an initial temperature at or near 4K (−452°F) actually fracture at temperatures significantly above 4K due to adiabatic heating. As a result of this work, ASTM E-23 test method on CVN testing was revised to incorporate a restriction that CVN tests are valid only at 77K (−320°F) and warmer. ASME requested PVRC to assess the above CVN issue and provide an appropriate recommendation for the Code change or for a further Code change, if needed for vessels with MDMT colder than 77K. PVRC formed a Task Group under the Committee on Failure Modes. The TG undertook a program which included a review of the existing data and an experimental program to develop new KIcJ data at 4K and 77K and CVN data at 77K. In the experimental program, a total of four 1-in-thick weldments were prepared from SA 240, Type 304 stainless steel plate using the SMAW process and E316L-15 electrodes. The electrodes purchased permitted the preparation of the weldments with four progressively higher levels of ferrite. The PVRC data and existing data were utilized in developing the recommendations to ASME. The recommendations are: use CVN tests (with 316L S.S. weld filler metal with FN⩽5) at 77K with increased acceptance criterion of 21 mils lateral expansion; for welds not meeting the foregoing requirements, use ASTM E1820 JIc tests at MDMT and the acceptance criterion for KIcJ has been set at 120 ksi√in. This paper presents the test data, analysis and technical basis for the PVRC recommendations to ASME.


2014 ◽  
Vol 587-589 ◽  
pp. 1954-1957 ◽  
Author(s):  
Yan Liu ◽  
Mao Xiang Lang

This paper mainly introduces the SVR method in the application of the railway freight volume forecasting. The paper analyzed the railway freight volume of eight major social and economic factors. Then, the paper selected learning samples and test method validation samples, through the normalized processing. It is concluded that the SVR to the effectiveness of the railway freight volume forecasting.<br />


2014 ◽  
Vol 16 (3) ◽  
pp. 586-591 ◽  
Author(s):  
Edward D. Bashaw ◽  
Binodh DeSilva ◽  
Mark J. Rose ◽  
Yow-Ming C. Wang ◽  
Chinmay Shukla

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