scholarly journals Uncertainty due to experimental conditions in co-ordinate measuring machines

Author(s):  
H Lobato ◽  
C Ferri ◽  
J Faraway ◽  
N Orchard

Any measurement method of a physical quantity cannot provide an exact unequivocal result owing to the infinite amount of information necessary to characterize fully both the physical quantity to be measured and the measuring process. Therefore, a quantitative indication of the quality of a measurement result needs to be given to enable its reliable use. Uncertainty is one such indication. Provision of incorrect uncertainty statements for measurements performed by a co-ordinate measuring machine (CMM) may lead to very serious economic implications. In this study, the uncertainty of CMM measurements is estimated by a single parameter accounting for both systematic and random errors. The effects that environmental conditions (temperature), discretionary set-up parameters (probe extension, stylus length), and measuring plan decisions (number of points) have on uncertainty of measurements are then investigated. Interactions between such factors are also shown to be significant.

At production of fabrics, including fabrics for agricultural purpose, an important role is played by the cor-rect adjustment of operation of machine main regulator. The quality of setup of machine main controller is determined by the proper selection of rotation angle of warp beam weaving per one filling thread. In the pro-cess of using the regulator as a result of mistakes in adjustment, wear of transmission gear and backlashes in connections of details there are random changes in threads length. The purpose of the article is the research of property of random errors of basis giving by STB machine regulator. Mistakes can be both negative, and positive. In case of emergence only negative or only positive mistakes operation of the machine becomes im-possible as there will be a consecutive accumulation of mistakes. As a result of experimental data processing for stable process of weaving and the invariable diameter of basis threads winding of threads it is revealed that the random error of giving is set up as linear function of the accidental length having normal distribution. Measurements of accidental deviations in giving of a basis by the main regulator allowed to construct a curve of normal distribution of its actual length for one pass of weft thread. The presented curve of distribution of random errors in giving of a basis is the displaced curve of normal distribution of the accidental sizes. Also we define the density of probability of normal distribution of basis giving errors connected with a margin er-ror operation of the main regulator knowing of which allows to plan ways of their decrease that is important for improvement of quality of the produced fabrics.


OENO One ◽  
2000 ◽  
Vol 34 (3) ◽  
pp. 101
Author(s):  
Jean-Pierre Robin ◽  
François-Xavier Sauvage ◽  
Martine Pradal ◽  
Marc Chovelon

<p style="text-align: justify;">Various conditions of vine « solarisation » with sun light reflecting clothes partially colored in blue, green or red, were performed in field conditions during 1998 and 1999 years.The experiments were conducted both on table grapes (Muscat de Hambourg , Italia and Danuta) and on wine grapes varieties (Carignane, Mourvèdre, Shiraz, Muscat à petits grains). The « solarisation » clothes were set up at the cluster closure stage and removed at the harvest time. Effect of various experimental conditions on changes <em>in situ</em> berry colour was examined. The chromatic parameters using the Lab and LCH conventional systems were weekly measured on representative berry samples, and levels of significance of the obtained differences were determined by a variance analysis. Differences in the colouring dynamics and in the values of the chromatic parameters at harvest were statistically significant, in particular in function of the importance of the reflecting area set up per vinestock and also in function of the color of the reflecting cloth used. The results were compared to those obtained from various other analyses : reflectance spectra and composition of berries at harvest, tastings of the table grapes. As a main result, the red colour with a maximum of reflectance at 680 nm appeared as the more effective in improving quality of the berries. These results demonstrate the importance of the reflectance properties of the neighbours of the vine, in particular those of the soil of the parcel, on the composition and the quality of the grape. Moreover, they underline that these properties should be taken in account to explain some misunderstood terroir effects. Finally, they strongly suggest that the excitation of vine photoreceptor systems, specially with the clear red light, could be decisive in the signaling and regulatory mechanisms leading to an optimal ripeness of the grape.</p>


1991 ◽  
Vol 24 (10) ◽  
pp. 171-177
Author(s):  
T. Vellinga ◽  
J. P. J. Nijssen

Much of the material dredged from the port of Rotterdam is contaminated to such a degree that it must be placed in specially constructed sites. The aim of Rotterdam is to ensure that the dredged material will once again be clean. This will entail the thorough cleansing of the sources of the contamination of the sediment in the harbours and in the River Rhine. The Rotterdam Rhine Research Project (RRP) is one of the means to achieve this based on: technical research, legal research, public relations and dialogues with dischargers. The programme for five selected heavy metals is almost complete. For many heavy metal discharge points between Rotterdam and Rheinfelden, a specially devised independent load assessment has been carried out four times. Balance studies were used to determine the relative contributions of the point discharges to the total. Currently the results are being used in an attempt to negotiate agreements with a selected number of the major dischargers. At present, more detailed balance studies are being set up and exploratory measurements carried out for organic micropollutants. It may be concluded that the research is progressing successfully and methods and techniques developed seem satisfactory and broadly applicable. The Rhine Action Programme encompasses an international effort to improve the quality of the Rhine water. Although the RRP plays a modest complementary role to the Rhine Action Plan, there is no doubt of the value of this Rotterdam initiative. The mode of work followed in the RRP contains elements that can be of use in combatting the contamination of the North Sea by rivers other than the Rhine.


1988 ◽  
Vol 20 (4-5) ◽  
pp. 249-251
Author(s):  
Jacques Bernard

The flow and the water quality of the rivers vary throughout the year. Very frequently the environment protection authorities set up a quality objective for the river water and this mini mum quality level is constant. So, it wou1d seem possible to accept variable quality standards for plant effluents. A first approach of the problem,by a small French task group,based on three actual cases leads to the provisory conclusion that such a regulation is suitable and presents economical benefit only in some very limit ed cases.


2015 ◽  
Vol 3 (2) ◽  
pp. 1-7 ◽  
Author(s):  
Achin Jain ◽  
M P Venkatesh M P ◽  
Pramod T.M. Kumar

In Tanzania, Tanzania Food and Drugs Authority (TFDA), is a regulatory body responsible for controlling the quality,safety and effectiveness of food, drugs, herbal drugs, cosmetics and medical devices. The Authority has been ensuringsafety, efficacy and quality of medicines by quality control tests; in addition to other quality assessment mechanisms.The guidelines laid by TFDA have also emanated from commitment to democracy and gives strong emphasis to thefulfilment of the needs of the less privileged rural population.Tanzania is an emerging market; the pharmaceutical market is valued at over US$250 million, and is growing at anannual rate of around 16.5% and is expected to reach approximately US$550 billion in 2020. Currently, the market ishighly dependent on imports, which account for around 75% of the total pharmaceutical market.The procedures and approval requirements of new drugs, variations, import, export and disposal have been set up bythe TFDA, which help in maintaining quality of the drug products that are imported as well being produced locally 


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Faiza Siddiqui ◽  
Marija Barbateskovic ◽  
Sophie Juul ◽  
Kiran Kumar Katakam ◽  
Klaus Munkholm ◽  
...  

Abstract Background Major depression significantly impairs quality of life, increases the risk of suicide, and poses tremendous economic burden on individuals and societies. Duloxetine, a serotonin norepinephrine reuptake inhibitor, is a widely prescribed antidepressant. The effects of duloxetine have, however, not been sufficiently assessed in earlier systematic reviews and meta-analyses. Methods/design A systematic review will be performed including randomised clinical trials comparing duloxetine with ‘active’ placebo, placebo or no intervention for adults with major depressive disorder. Bias domains will be assessed, an eight-step procedure will be used to assess if the thresholds for clinical significance are crossed. We will conduct meta-analyses. Trial sequential analysis will be conducted to control random errors, and the certainty of the evidence will be assessed using GRADE. To identify relevant trials, we will search Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, PsycINFO, Science Citation Index Expanded, Social Sciences Citation Index, Conference Proceedings Citation Index—Science and Conference Proceedings Citation Index—Social Science & Humanities. We will also search Chinese databases and Google Scholar. We will search all databases from their inception to the present. Two review authors will independently extract data and perform risk of bias assessment. Primary outcomes will be the difference in mean depression scores on Hamilton Depression Rating Scale between the intervention and control groups and serious adverse events. Secondary outcomes will be suicide, suicide-attempts, suicidal ideation, quality of life and non-serious adverse events. Discussion No former systematic review has systematically assessed the beneficial and harmful effects of duloxetine taking into account both the risks of random errors and the risks of systematic errors. Our review will help clinicians weigh the benefits of prescribing duloxetine against its adverse effects and make informed decisions. Systematic review registration PROSPERO 2016 CRD42016053931


2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
B Holmes ◽  
U Mirza ◽  
C Manning ◽  
R Cooke ◽  
R Jugdey

Abstract Introduction COVID-19 has placed unprecedented demand on services at ELHT and it has become necessary to have telephone clinics to reduce the number of face-to-face clinics. A ‘telephone triage clinic’ was set up for referrals from A&E. Our project evaluated patient and clinician satisfaction on this. Method We carried out a retrospective telephone questionnaire with patients over a one-week period during the pandemic. We focussed on overall satisfaction of the consultation and quality of communication. Consultants were also surveyed for their opinion on the clinics. Results From 30 patients, 77% said they were ‘very satisfied’ with the overall experience. 80% of patients were ‘very satisfied’ with the overall length of the telephone consultation. 50% of patients felt the clinician was only ‘adequately’ able to assess them over the telephone. The consultants were less satisfied with the overall experience of telephone consultation. A common theme was that they felt ED documentation could be improved to help inform ongoing management. Conclusions Overall, patients were satisfied with the consultations. It has been successful in minimising face to face consultations however some presentations necessitate further evaluation. We need to identify those injuries appropriate for virtual follow up and design a local protocol for these.


2020 ◽  
pp. 097300522096468
Author(s):  
Rajesh Gupta ◽  
Piyush Kumar Sinha ◽  
Akash Sahu ◽  
Vandana Sood

Craft industry is as much the mainstay of the rural economy after agriculture. It provides occupation to a large section of population. However, it is characterised by fragmented individual artisans on one side and dispersed customers on the other. It also suffers from market separations. Urban haats were set up with the objective to present artisans and buyer on one platform and reduce these separations. In this study urban haats have been conceptualised as marketplaces that bring artisans and customers at one place to optimise their respective values. They also serve as a tool for disintermediation and a social distribution initiative and represent a retailing initiative in the inclusive entrepreneurship domain. This study focusses on identifying drivers of success of urban haats. Using a mixed method approach, data was collected from Haat officials and NGO members through personal interviews. The data from artisans and customers was collected through a survey using a structured response format. The study was conducted at 18 haats in 10 states. The study highlights the factors that drive satisfaction of artisans and customers and the role of administrators in making the marketplace a success. Customer consider diversity of the products, quality of the products, behaviour of the salesperson, price parity with other markets, buying experience, parking space and aesthetics of the stalls as major influencing factors for the recommendation of the haats to other customers. Most important attributes of the haats in driving artisan satisfaction were stall allotment system, haat location, advertisements, product promotion and monitoring. It is also found that while the infrastructure is necessary, it is not sufficient in enhancing the performance and sustainability of haats. Administration of these haats plays a defining mediating role. Based on these findings, an approach is proposed for success of urban haats.


2021 ◽  
pp. 019262332198965
Author(s):  
Jeffrey C. Wolf

A number of studies have investigated the potential toxicity of the analgesic agent diclofenac (DCF) in various fish species under a diverse array of experimental conditions. Reported evidence of toxicity in these investigations is often strongly reliant on morphologic end points such as histopathology, immunohistochemistry, and transmission electron microscopy. However, it may be challenging for scientists who perform environmental hazard or risk determination to fully appreciate the intricacies of these specialized endpoints. Therefore, the purpose of the current review was to critically assess the quality of morphologic data in 14 papers that described the experimental exposure of fish to DCF. Areas of focus during this review included study design, diagnostic accuracy, magnitude of reported changes, data interpretation and presentation, and the credibility of individual reported findings. Positive attributes of some studies included robust experimental designs, accurate diagnoses, and straightforward and transparent data reporting. Issues identified in certain articles included diagnostic errors, failure to account for sampling and/or observer bias, failure to evaluate findings according to sex, exaggeration of lesion severity, interstudy inconsistencies, unexplained phenomena, and incomplete or ambiguous data presentation. It is hoped that the outcome of this review will be of value for personnel involved in regulatory decision-making.


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