scholarly journals MATERIAL TEST AND RESULTS ESTIMATION BY SAFETY INDEXES

2021 ◽  
Vol 82 (2) ◽  
pp. 38-45
Author(s):  
Mykola Mykyjchuk ◽  
◽  
Y. Rudyk ◽  

In the article, both the test method features and the test results of research of thermal behavior of steel fragment were analyzed. Two types of test conditions for steel construction material were considered. The definition and main features of measurement techniques were presented. Fire retardant material test results for steel plates with hydrogen combustion shown the limit of fire resistance of the tested samples is more than 30 min. The main advantages and disadvantages of the test were determined. The positive and negative aspects of this approach were analyzed. These techniques' effective thermal condition is in an environment of uncertainty and has no limited resources was established. Concepts and principles for establishing validity, and frameworks and methods for validating test methods and their results are important elements of safety systems. The article considers the safety of the technical component of a complex organizational and technical system with the study of the functional relationship between the safety elements parameters: temperature, time, fire retardant – by hydrogen participation.

2017 ◽  
Vol 726 ◽  
pp. 414-418
Author(s):  
Bo Fu ◽  
Hui Wang ◽  
Zhu Feng Shao

The optical quartz glass is widely applied in optical system , photo communications,inertial navigation,etc.It must have high optical homogeneity. Optical homogeneity of the optical quartz glass directly affects the wavefront quality of the optical transmission system, and changes the wavefront aberration of the system. How to accurately determine the optical homogeneity of the quartz glass is especially important. Currently,the method of test for optical homogeneity mainly used by interference principle. This paper analyzes various existing interference measurement method and test equipment. Summarized the advantages and disadvantages of various test methods,using range and measurement accuracy.


2021 ◽  
Author(s):  
Rui Yang ◽  
Xiaobin Li ◽  
Hongxi Li

Abstract In this paper, the vibration characteristics of laminated composite cantilever beam is taken as the research object. Firstly, a vibration formula specific for laminated composite cantilever beam is derived, from which the low order natural frequency of laminated composite cantilever beam is calculated; Secondly, two experimental methods, electrical and optical measurement, are used to study the vibration characteristics of laminated composite cantilever beam, and the influence of different test methods, sensor types, number of measuring points and excitation methods on the test results are analyzed. Through the combination of theory and experiment, a test method that can be applied to the vibration test of composite material laminated structure cantilever beam is obtained. Based on the laser vibration measurement method in the optical method, the results show that the deviation between the experimental data and the theoretical solution is the smallest when the distance between the probe and the specimen is 0.5m and the sampling time is 5s by using the optical fiber vibrometer. The research content of this article can provide a reasonable reference for related vibration test research.


1982 ◽  
Vol 45 (13) ◽  
pp. 1257-1260 ◽  
Author(s):  
DALE L. SCHEUSNER

Methods to evaluate germicides can be grouped into three categories: standard laboratory tests, in-use tests and simulated-use tests. Standard laboratory methods, such as the Available Chlorine Germicidal Equivalent test, are specifically defined for reproducibility in any laboratory by any operator, but the test results often lack relevance to actual product-use conditions. In-use test methods are relevant to product-use; however, in-use test procedures do not permit proper controls to be included in the organism recovery methods. Contact plates give an estimate of organism numbers which is only 25% of the theoretical number of organisms present. Organism recovery using a swab, cellulose sponge or tube sampler give estimates of organisms ranging from 91 to 111% of theoretical. The tube sampler is a 1-in. length of flexible tubing having a 1-in. interior diameter and a smooth end, which can make a water-tight seal on a flat surface. Simulated use testing yields data which are relevant to actual product-use. A cafeteria tray is soiled, inoculated and cleaned in a manner to simulate actual product-use. This test method permits the necessary controls to be used. Tray-test reproducibility is as good as that of the other recovery methods tested and organism recovery is quantitative. The tray test provides a means for determining biological cleaning where the effect of both cleaning and germicidal activity are measured together.


2003 ◽  
Vol 11 (3) ◽  
pp. 219-227 ◽  
Author(s):  
Chris Kneale

Many factors need to be considered in the design of new biocides for use in plastics applications. In Europe, biocides are now becoming more tightly regulated under the Biocidal Products Directive (BPD), and a significant data package needs to be provided not only for the registration of new actives, but also for existing biocides and biocidal formulations. A novel biocide must be compatible with the polymer matrix and must not adversely affect its physical properties. Once the issue of compatibility has been overcome, the antimicrobial efficacy of the biocide in the substrate should be established. Before selecting a test method to demonstrate such efficacy, it is necessary to consider whether the substrate should be pre-conditioned to simulate end use conditions, e.g. by leaching or artificial weathering. The final use of the product can also dictate the test protocol, e.g. a building membrane for ground contact should be evaluated using a soil burial test. Historically, biocides have been added to plastics to prevent their spoilage by fungal attack. Latterly, plastics with antibacterial effects have aroused much public interest. Advantages and disadvantages of traditional test methods will be discussed, and an alternative method for the evaluation of biocidal performance that is thought to be more representative of end use conditions will be presented.


2015 ◽  
Vol 27 (4) ◽  
pp. 476-488 ◽  
Author(s):  
Nellie Gagné ◽  
Anne Veniot ◽  
Mary Stephenson ◽  
Carol McClure

Fitness for purpose and validation are increasingly becoming a benchmark in the development of test methods for the diagnosis of infectious diseases in aquatic animals. The design of the evaluation and the analysis of data are critical to demonstrate test method performance characteristics and fitness for purpose, as stated in the World Organization for Animal Health pathway for test validation. Three test methods for the detection of the oyster parasite Haplosporidium nelsoni were selected for the validation study described herein: histology, end-point polymerase chain reaction (PCR), and real-time PCR (qPCR). Preliminary work evaluated the analytical sensitivity and specificity of the PCR and qPCR assay in development. The following stage used test results on 100 oysters in 3 different laboratories to assess diagnostic sensitivity (DSe), diagnostic specificity (DSp), repeatability, and reproducibility. Repeatability and reproducibility were within 68–95%. The final part of the project evaluated DSe and DSp using test results on 400 oysters and results from the first 100 oysters tested. In the absence of a 100% gold standard test, latent class modeling methods were explored to characterize the tests (i.e., Bayesian analyses). For both PCR methods, DSe was >90%, and in the 60% range for histology, whereas DSp was >90% for all methods. Based on the results of this validation, a threshold cycle value of 30 for qPCR corresponds to the limit of sensitivity for histology where unreliable detection becomes more frequent, thus providing a threshold helpful in diagnostic settings where both histology and qPCR are used.


2013 ◽  
Vol 756-759 ◽  
pp. 138-140 ◽  
Author(s):  
Yun Sen Sun ◽  
Bo Qiu ◽  
Qing Shan Li

We developed a device for automatic closed friction and analyzed its test results in this paper, which showed the influence factors in the test methods of textile negative ion occurrence amounts. The textile negative ion occurrence amounts in different time stages were tested in this process; the analysis of its influence of temperature and humidity has certain reference significance for improving testing device for testing textile negative ion concentration, on the basis, functional textiles were also studied. Finally, we put forward the influence factors in the test methods of textile negative ion occurrence amounts.


2009 ◽  
Vol 132 (3) ◽  
Author(s):  
Zuo Lei ◽  
Sukang Zhu ◽  
Ning Pan

Fibrous material is a complex porous medium and steady test methods are the main test approaches we currently depend on to study the heat transfer properties. The application of unsteady test methods on fibrous material is still not mature. In this paper, some systematic studies are taken to investigate this problem. By analyzing the main factors impacting the test results, it is found that the local heat convection potentially excited by imposing test temperature can be avoided by limiting the internal temperature gradient and the so-called dual-phase lagging effects are negligible so that the feasibility of the unsteady test method is verified via both theoretical analysis and experimental data.


1999 ◽  
Vol 5 (1) ◽  
pp. 74-78 ◽  
Author(s):  
Albertas Nyderis

The Directive of new approach 89/106/EEC, which was prepared by Directorate General of the European Commission (DG III), defines the guidelines for development of fire protection in building construction. Six main directions for development of fire protection are defined in this Directive as well. Solid materials are most numerous among building products. Therefore a brief analysis of combustion process of these materials is presented in this article. F.Williams developed the theoretical principles of combustion. Phase transitions in the zone of combustion are analyzed in the theory. Formulas 1–4 describe this process. The process of combustion of solid materials is heterogeneous; therefore the model of pyrolysis is presented by 5 formulas. An intricate energy exchange takes place in real fires. The heat is being transferred in different ways. The most acceptable description of heat transfer is by means of radiation. Description of this process is presented in formulas 6–7. The heat transfer by means of radiation can be modelled and used for environment testing. The combustibility of building products can be examined by means of reaction of fire tests. In recent years tests for different building products were carried out according to ISO 5657 test methodology in the Fire Research Centre. Test results indicate that the time to sustained surface ignition for building products is inversely proportional to heat flux. This logarithmic dependence is presented in 8 formulas. Establishment of parameters of this logarithmic flow for different building products can prove this. This work was carried out during the process of verification of this hypothesis. Analysis of fire testing practice of vertically oriented building products in different countries shows that harmonized fire test methods for these products do not exist. Most of these test methods are based on presumption that the flame spread is possible only inside the building not considering the behaviour of facade in fire. The main idea of fire test method for element of vertically oriented building construction together with the principal scheme of test equipment are presented in the article as well. Further development of this idea leads to five questions, which should be answered to solve the problem. After the completion of this task and analysis of test results, all the information is to be submitted for further consideration.


2018 ◽  
Vol 19 (12) ◽  
pp. 620-624
Author(s):  
Tomasz Rochatka

The article presents a description of the structure of isothermal and refrigeration bodies, their sensitivity to mainly mechanical damage and examples of various types of damage. Presenting damage to the body, the mechanism of creation is described, damage is shown using thermographic images and the consequences of these damages are discussed. The article contains a description of the methods of examination of body damages, presenting the advantages and disadvantages of the test methods. The test results can be the basis for making a decision about further operation or qualification for repair.


2018 ◽  
Vol 227 ◽  
pp. 01001
Author(s):  
Jiangtao Song ◽  
Yan Zhao ◽  
Yu Li

To guarantee the successful completion of airworthiness certification test for a certain type of aircraft, the leakage and discharge compliance criteria of flammable liquid were designed by studying airworthiness requirements and the design characteristic of the civil aircraft, where flammable liquid leakage zones and hazardous zones in which liquids are not allowed to enter were determined. Further the test equipments and the dyeing liquor for replacing flammable fluid were developed, and ground and flight test methods were proposed. Moreover, the above test equipment and methods were applied to flight tests of flammable liquid leakage and discharge for certain civil aircraft. The test results show that the test equipment is stable and reliable, and the flight test method can accurately demonstrate the flammable liquid leakage and discharge.


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