Paints and varnishes � On-site test methods on quality assessment for interior wall coatings

2020 ◽  
2017 ◽  
Vol 35 (7) ◽  
pp. 730-738 ◽  
Author(s):  
Atsushi Yamawaki ◽  
Yoichi Doi ◽  
Kiyoshi Omine

2014 ◽  
Vol 638-640 ◽  
pp. 1676-1682
Author(s):  
Zong Yang Yuan ◽  
Hong Yao Sun ◽  
Zheng Yang ◽  
Ming Xia Shen ◽  
Guo Liang Shan

The organosilicon hydrophobic impregnants is applied on concrete to prevent rebar corrosion with its water repellent property which can prevent the intrusion of chloride and other harmful media. On-site the parameters of organosilicon hydrophobic impregnants of controlling quality consist of resistance to chloride penetration, water absorption of concrete and impregnating depth of organosilicon hydrophobic impregnants. The status of test methods of these parameters is summarized and their advantages and disadvantages are briefly reviewed. Finally some ideas are presented about shortcomings of test methods.


2020 ◽  
Vol 2020 (11) ◽  
pp. 69-1-69-7
Author(s):  
Ashutosh Singla ◽  
Stephan Fremerey ◽  
Frank Hofmeyer ◽  
Werner Robitza ◽  
Alexander Raake

In recent years, with the introduction of powerful HMDs such as Oculus Rift, HTC Vive Pro, the QoE that can be achieved with VR/360° videos has increased substantially. Unfortunately, no standardized guidelines, methodologies and protocols exist for conducting and evaluating the quality of 360° videos in tests with human test subjects. In this paper, we present a set of test protocols for the evaluation of quality of 360° videos using HMDs. To this aim, we review the state-of-the-art with respect to the assessment of 360° videos summarizes their results. Also, we summarize the methodological approaches and results taken for different subjective experiments at our lab under different contextual conditions. In the first two experiments 1a and 1b, the performance of two different subjective test methods, Double-Stimulus Impairment Scale (DSIS) and Modified Absolute Category Rating (M-ACR) was compared under different contextual conditions. In experiment 2, the performance of three different subjective test methods, DSIS, M-ACR and Absolute Category Rating (ACR) was compared this time without varying the contextual conditions. Building on the reliability and general applicability of the procedure across different tests, a methodological framework for 360° video quality assessment is presented in this paper. Besides video or media quality judgments, the procedure comprises the assessment of presence and simulator sickness, for which different methods were compared. Further, the accompanying head-rotation data can be used to analyze both content- and quality-related behavioural viewing aspects. Based on the results, the implications of different contextual settings are discussed.


1987 ◽  
Vol 1 (4) ◽  
pp. 203
Author(s):  
A. Wilson ◽  
L.D. Hall
Keyword(s):  

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3475
Author(s):  
Izabela Skrzypczak ◽  
Agnieszka Leśniak ◽  
Piotr Ochab ◽  
Monika Górka ◽  
Wanda Kokoszka ◽  
...  

Proper quality assessment of ready-mixed concrete, which is currently the principal material for construction, land engineering and architecture, has an impact on the optimisation and verification of correct functioning of individual stages of the production process. According to the European Standard EN 206 “Concrete–Specification, performance, production and conformity”, obligatory conformity control of concrete is carried out by the producer during its production. In order to verify the quality of concrete, investors generally commission independent laboratory units to perform quality assessment of both concrete mix and hardened concrete, which guarantees a high quality of construction works. One of the essential tools for ensuring the quality of test results is the participation of laboratories in the so-called proficiency testing (PT) or inter-laboratory comparisons (ILC). Participation in PT/ILC programmes is, on the one hand, a tool for demonstrating the laboratory’s performance, on the other hand an aid for maintaining the quality of available concrete tests and validating test methods. Positive evaluation is a confirmation of the laboratory’s capability for performing the tests. The paper presents the results of laboratory proficiency tests carried out by means of inter-laboratory comparisons, as shown in the example of quality assessment of ready-mixed concrete for nine participating laboratories. The tests were performed for concrete of the following parameters: strength class C30/37, consistency S3, frost resistance degree F150, and water resistance degree W8. This involved determining consistencies, air content and density of the concrete mix, and compressive strength of hardened concrete. For the evaluation of laboratory performance results, z-score, ζ-score and En-score were applied. The innovation of the proposed study lies in employing both classical and iterative robust statistical methods. In comparison with classical statistical methods, robust methods ensure a smaller impact of outliers and other anomalies on the measurement results. Following the analyses, clear differences were found between the types of detected discrepancy of test results, which occurred due to the nature of individual parameters. For two laboratories, two scores revealed unsatisfactory results for concrete mix consistency. The main reasons can be pouring into the cone-shaped form a concrete mixture that is too dry, or incorrect use of a measuring tool also creating a possibility that the obtained value can be wrongly recorded. Other possible reasons are discussed in the paper. Participation in inter-laboratory comparison programmes is undoubtedly a way to verify and raise the quality of tests performed for concrete mix and hardened concrete, whereas individual analysis of the results allows the laboratory quality system to be improved.


2021 ◽  
Vol 26 (09) ◽  
Author(s):  
Jorge Palma-Chavez ◽  
T. Joshua Pfefer ◽  
Anant Agrawal ◽  
Jesse V. Jokerst ◽  
William C. Vogt

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