scholarly journals Laboratory investigations on the quality of leak tests and visual inspections of wastewater connection pipes carried out by specialist contractors

2021 ◽  
Author(s):  
S. Ulutaş ◽  
M. Wichern ◽  
B. Bosseler
Keyword(s):  
Water Pressure ◽  
Test Methods ◽  
Test Results ◽  
Damage Classification ◽  
Air Overpressure ◽  
Normative Requirements ◽  
Leak Tightness ◽  
Laboratory Investigations ◽  
Test Errors

Abstract In addition to stability and operational safety, leak tightness is the permanent functional objective of wastewater pipes. Tests to determine the tightness of wastewater pipes can in some cases produce results that are worthy of discussion. Therefore, laboratory tests were carried out by 29 specialist contractors to obtain results on the quality of leak tests and visual inspections of connection pipes. The results showed that different test errors can be observed for leak test methods (air overpressure, air underpressure and water pressure). However, only in the case of the water pressure tests did the observed test errors occasionally lead to incorrect test results, i.e. the ‘leaking pipe’ was tested as ‘test passed (tight)’. The investigations into the accuracy (trueness and precision) of the test methods showed that all test methods examined were sufficiently accurate to determine the tightness of the connection pipes. In general, correct test results were achieved if the expert testers did not make any serious test errors and the test equipment used functioned properly. In contrast, the investigations on the quality of visual inspection showed that the procedure is not sufficiently reliable to fulfil all normative requirements regarding damage detection and naming as well as damage classification.

Test Methods for Evaluation of Cold-Applied Bituminous Patching Mixtures

1997 ◽  
Vol 1590 (1) ◽  
pp. 10-16 ◽  
Author(s):  
Cindy K. Estakhri ◽  
Joe W. Button
Keyword(s):  
Test Procedure ◽  
Test Methods ◽  
Test Results ◽  
Department Of Transportation ◽  
Unconfined Compression ◽  
Test Procedures ◽  
Unconfined Compression Test ◽  
Texas Department ◽  
Before And After

A Texas Department of Transportation study performed by the Texas Transportation Institute was undertaken with a goal of providing methods to assure the quality of cold-applied, asphalt-stabilized maintenance mixtures. Test procedures and acceptance criteria were developed for hot-mix, cold-laid asphalt concrete patching mixtures. Two specific objectives were to develop a test procedure to simulate approximately six months of stockpile-aging and a test procedure to quantify workability of maintenance mixtures. The protocol developed is designed to estimate the relative ability of a maintenance mixture to retain adequate workability after outdoor stockpile storage. This protocol could be useful as part of a specification to promote quality. Two test procedures were evaluated regarding their potential to quantify the workability of maintenance mixtures: a triaxial test and an unconfined compression test. Test results indicated that both procedures provide a relatively good measure of workability before and after aging. Two laboratory aging procedures were evaluated for their ability to predict workability of a stockpiled maintenance mixture after six months of field aging. Procedure A appeared to provide a reasonable approximation of six months of field aging.

scholarly journals Interlaboratory Comparative Tests in Ready-Mixed Concrete Quality Assessment

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3475
Author(s):  
Izabela Skrzypczak ◽  
Agnieszka Leśniak ◽  
Piotr Ochab ◽  
Monika Górka ◽  
Wanda Kokoszka ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Statistical Methods ◽  
Test Methods ◽  
Hardened Concrete ◽  
Proficiency Tests ◽  
Test Results ◽  
Concrete Mix ◽  
Ready Mixed Concrete ◽  
Mixed Concrete

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.

Implementasi Voip Server Berbasis IPV6 Dengan Raspberry PI

2019 ◽  
Vol 9 (01) ◽  
pp. 47-54
Author(s):  
Rabbai San Arif ◽  
Yuli Fitrisia ◽  
Agus Urip Ari Wibowo
Keyword(s):  
Internet Protocol ◽  
Wireless Transmission ◽  
Raspberry Pi ◽  
Test Results ◽  
Average Delay ◽  
Ipv6 Network ◽  
Ip Network ◽  
Selection Of ◽  
Better Than

Voice over Internet Protocol (VoIP) is a telecommunications technology that is able to pass the communication service in Internet Protocol networks so as to allow communicating between users in an IP network. However VoIP technology still has weakness in the Quality of Service (QoS). VOPI weaknesses is affected by the selection of the physical servers used. In this research, VoIP is configured on Linux operating system with Asterisk as VoIP application server and integrated on a Raspberry Pi by using wired and wireless network as the transmission medium. Because of depletion of IPv4 capacity that can be used on the network, it needs to be applied to VoIP system using the IPv6 network protocol with supports devices. The test results by using a wired transmission medium that has obtained are the average delay is 117.851 ms, jitter is 5.796 ms, packet loss is 0.38%, throughput is 962.861 kbps, 8.33% of CPU usage and 59.33% of memory usage. The analysis shows that the wired transmission media is better than the wireless transmission media and wireless-wired.

POLARYZACJA GRUPOWA W WARUNKACH DEBATY DELIBERATYWNEJ

2014 ◽  
Vol 2 (2) ◽  
pp. 19-29
Author(s):  
Elżbieta Wesołowska
Keyword(s):  
Social Psychology ◽  
John Rawls ◽  
Empirical Data ◽  
Group Decision ◽  
Group Discussion ◽  
Positive Outcomes ◽  
Group Consensus ◽  
Group Polarization ◽  
Normative Requirements

In social psychology the group polarization refers to the tendency for groups to make decisionsthat are more extreme than the initial inclinations of its members. This phenomenon constitutesa potential obstacle to positive outcomes attributed to deliberative debates. A deliberative debateis a particular kind of a group discussion tasked with fi nding group consensus on controversialissues. The idea of deliberation originates from the writings of John Rawls, Jürgen Habermas, AmyGutmann and Denis Thompson. Deliberative debate imposes numerous normative requirementson the communication, relationships among the disputants and their approach to the issue underdiscussion. These normative requirements make a big difference between deliberative debates andthe situations in which the phenomenon of polarization was observed. Thus, we presume that indeliberative debates conditions the phenomenon of group polarization may be limited.The paper investigates the following questions: would the normative conditions of deliberationlimit the occurrence of polarization in discussing groups? and What infl uence (if any) would thepolarization process have on the quality of group decision? In the light of the empirical data we concluded what follows: (1) In 50% of the analyzed casesof group discussion the phenomenon of group polarization was observed despite the normativeconditions of deliberation. (2) The occurrence of group polarization in some cases coincided withmaking the fi nal decisions which did not alter the initial preferences of the disputants (but did nottotally predestinated the fi nal outcome).

Analisa Pengujian Repeatability Timbangan Elektronik dengan Metode Syarat Teknis Timbangan Non Otomatis dan Metode NMI Australia

2019 ◽  
Vol 4 (2) ◽  
pp. 176-183
Author(s):  
Ponco Wali
Keyword(s):  
Research Method ◽  
Test Methods ◽  
Test Results ◽  
Repeat Testing ◽  
Testing Method ◽  
Technical Requirements

Testing repeat electronic scales with non-automatic scales technical requirements so far is fairly long if not using a calculator or computer. The aim of this research is to compare the repeatability testing method of electronic scales using methods according to the technical requirements of non-automatic scales and the Australian NMI method, both of which refer to OIML R76 in determining the validity or cancellation of electronic scales repeatability testing. This research method is done through repeat testing on 3 samples of electronic scales, then on each electronic scale 2 test methods are performed. The conclusion is that the electronic scales repeatability testing uses the non-automatic scales technical requirements method and the Australian NMI method has some differences although both refer to OIML R76. These differences include several points, namely the charge used, the method of adding additions, the formula for determining electronic scales, and different test results. The Australian NMI method is deemed to make it easier and more time efficient compared to the non-automatic weighing technical requirements method.

Sinonasal effects of external dacryocystorhinostomy

2021 ◽  
pp. 1-4
Author(s):  
H Eyigor ◽  
E A Cetinkaya ◽  
D T Coban ◽  
G Ozturk ◽  
Ö Erdem
Keyword(s):  
Mucociliary Clearance ◽  
Nasal Symptom ◽  
Ciliary Activity ◽  
Test Results ◽  
Saccharine Test ◽  
Significant Difference ◽  
Symptom Scores ◽  
Endoscopic Score ◽  
External Dacryocystorhinostomy

Abstract Objective External dacryocystorhinostomy is thought to cause mucociliary dysfunction by damaging the mucosa, in turn affecting ciliary activity and mucus quality. This study investigated the effect of external dacryocystorhinostomy on sinonasal function. Methods Patients scheduled for unilateral external dacryocystorhinostomy who underwent endoscopic nasal examination and paranasal sinus computed tomography were included in this study. A saccharine test was performed on the planned surgical side and the mucociliary clearance time was determined. The sinonasal quality of life was measured in all patients, pre-operatively and at six months post-operatively, using the Sino-Nasal Outcome Test-22. The Lund–Kennedy endoscopic score was also determined in all patients, both pre- and post-operatively. Results The study comprised 28 patients (22 females and 6 males). A statistically significant difference was found between the pre- and post-operative saccharine test results (p = 0.006), but not between the pre- and post-operative Sino-Nasal Outcome Test-22 scores (p > 0.05). Conclusion This study is one of only a few to investigate the effect of external dacryocystorhinostomy on sinonasal function. The results showed that external dacryocystorhinostomy impairs mucociliary clearance. The surgical procedure is well tolerated and does not significantly change nasal symptom scores.

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun
Keyword(s):  
Quality Control ◽  
Test Methods ◽  
In Vitro Test ◽  
Large Numbers ◽  
Alternative Approach ◽  
Inactivated Vaccines ◽  
Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

scholarly journals Comparison of Two Intergranular Corrosion Tests on EN AW-6016 Sheet Material

2021 ◽  
Vol 11 (11) ◽  
pp. 5294
Author(s):  
Peer Decker ◽  
Ines Zerbin ◽  
Luisa Marzoli ◽  
Marcel Rosefort
Keyword(s):  
Optical Microscopy ◽  
Intergranular Corrosion ◽  
Sheet Material ◽  
Test Methods ◽  
Standard Test ◽  
Corrosion Depth ◽  
Corrosion Tests ◽  
Automotive Company ◽  
Test Parameters

Two different intergranular corrosion tests were performed on EN AW-6016 sheet material, an ISO 11846:1995-based test with varying solution amounts and acid concentrations, and a standard test of an automotive company (PV1113, VW-Audi). The average intergranular corrosion depth was determined via optical microscopy. The differences in the intergranular corrosion depths were then discussed with regard to the applicability and quality of the two different test methods. The influence of varying test parameters for ISO 11846:1995 was discussed as well. The determined IGC depths were found to be strongly dependent on the testing parameters, which will therefore have a pronounced influence on the determined IGC susceptibility of a material. In general, ISO 11846:1995 tests resulted in a significantly lower corrosion speed, and the corrosive attack was found to be primarily along grain boundaries.

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