scholarly journals Evaluation of the Magnet Breakaway Force Measurement Accuracy of the NT-800 Sensors for Early Detection of Defects of Their Manufacturing

2021 ◽  
Vol 12 (3) ◽  
pp. 230-238
Author(s):  
A. Yu. Kutsepau ◽  
A. P. Kren ◽  
Y. V. Hnutsenka
Keyword(s):  
Measurement Error ◽  
Sensitive Element ◽  
Force Measurement ◽  
Variation Coefficient ◽  
Internal Stresses ◽  
Good Precision ◽  
Informative Parameter ◽  
Labor Costs ◽  
National Academy Of Sciences ◽  
Repeatability And Reproducibility

Сontrol of mechanical stresses formed with the deposition of nickel coatings plays an important role in the diagnosis of coatings’ technical condition. Large internal stresses can lead to cracking or flaking of coatings which is completely unacceptable for critical parts and assembly units used, for example, in space technology for which reliability is of paramount importance. An important aspect of internal stresses monitoring is the measurement error of the instruments used. The purpose of this work was to determine the characteristics of the device sensors, which make the assessment of their manufacturing possible at the preliminary stage of the measuring equipment assembling in order to maintain the required accuracy of subsequent measurements.In most cases the measurement error assessment is possible only after the equipment manufacture and calibration. In this paper it is proposed to evaluate the accuracy characteristics of device sensors based on the precision (repeatability and reproducibility) of the primary informative parameter recording. In the case of the NT-800 device that was developed at the Institute of Applied Physics of the National Academy of Sciences of Belarus the effect of precision characteristics deterioration on the eventual measurement error is demonstrated. Determining the precision parameters before establishing correlation dependences between the primary informative parameter and the measured characteristic is proposed in order to reject poorly manufactured sensors and reduce labor costs.In particular, measurements of the magnitude proportional to the magnetic breakaway force were carried out using the NT-800 device with nickel specimens simulating coatings with a thickness of 200 to 700 μm and a rolling value from 0 to 40 %. It was established that in the case of well-made sensors the variation coefficient calculated from the dispersion of repeatability is in the range 0.2–0.6 %, and the variation coefficient calculated from the dispersion of reproducibility does not exceed 0.9 %. In the case of a sensor with the sensitive element parameters worsened, the variation coefficient of repeatability and reproducibility were up by one and a half times. Deterioration of the precision characteristics resulted in significant changes in the readings of the calibrated instrument. Thus the absolute measurement error for a sensor with a poorly made sensitive element turned out to be approximately 3 times higher in the range of 200– 300 MPa than that for a sensor with good precision parameters.

Design and Measurement Error Analysis of a Low-Friction, Lightweight Linear Series Elastic Actuator

2013 ◽  
Author(s):  
Bryce Lee ◽  
Viktor Orekhov ◽  
Derek Lahr ◽  
Dennis Hong
Keyword(s):  
Measurement Error ◽  
Error Analysis ◽  
Measurement Errors ◽  
Position Control ◽  
Force Measurement ◽  
Compliant Mechanism ◽  
Load Cell ◽  
Low Friction ◽  
Linear Guide ◽  
Series Elastic

Series elastic actuators (SEAs) have many benefits for force controlled robotic applications. Placing an elastic member in series with a rigid actuator output enables more-stable force control and the potential for energy storage while sacrificing position control bandwidth. This paper presents the design and measurement error analysis of a low-friction, lightweight linear SEA used in the Shipboard Autonomous Fire Fighting Robot (SAFFiR). The SAFFiR SEA pairs a stand-alone linear actuator with a configurable compliant member. Unlike most electric linear actuators, this actuator does not use a linear guide, which reduces friction and weight. Unlike other SEAs which measure the force by measuring the spring deflection, a tension and compression load cell is integrated into the design for accurate force measurements. The configurable compliant member is a titanium cantilever with manually adjustable length. The final SEA weighs 0.82[kg] with a maximum force of 1,000[N]. The configurable compliant mechanism has in a spring constant range of 145–512[kN/m]. Having no linear guide and incorporating the load cell into the universal joint both introduce measurement errors. The length error across a parallel ankle joint is less than 0.015[mm] and the force measurement error is less than 0.25% of the actual force. Finally, several changes are suggested for the next iteration of the SEA to improve its usability on future robots.

scholarly journals Validasi Metode Penentuan Mn Dalam Oli Lubrikan Dengan Metode Pengenceran Langsung Menggunakan Spektrofotometer Serapan Atom

2019 ◽  
Vol 6 (2) ◽  
pp. 94-100
Author(s):  
Rona Maningting Napitupulu ◽  
Dirgarini Julia ◽  
Aman S. Panggabean
Keyword(s):  
Detection Limit ◽  
Limit Of Detection ◽  
Lubricating Oil ◽  
Dilution Method ◽  
Good Precision ◽  
Validation Method ◽  
Limit Of Quantitation ◽  
Environment Control ◽  
Repeatability And Reproducibility

Validation method on the determination of Mn in lubricating oil by direct dilution method using Atomic Absorption Spectrophotometer (AAS) in Laboratory & Environment Control PT. Badak NGL Bontang has been done The validation method was done with research stages such as determination of  optimum solvent, and determination of some important parameters influential for validation method such as parameter of liniearitas (r), Instrument Detection Limit (IDL), Methode Detection Limit (MDL), accuracy, precision, Limit of Detection(LOD) and Limit of Quantitation(LOQ). The result of research obtain is good, showed that the linearity value with R2 ≥ 0,997. The IDL and MDL value was 0.0021 ppm and 0.0092 ppm respectively and has been acceptability requirements of MDL. The accuracy paramater obtained recovery value with range 82.25-88.34%. The measurement of repeatability and reproducibility, the CV Horwitz value smaller than % RSD, indicating the method had a good precision. The measurement of  LOD and LOQ value was 0.095 ppm 0.317 ppm respectively. Based on the result of the research determination method of Mn in lubricating oil by direct dilution method using AAS concluded valid.

scholarly journals THE ORGANIZATION OF CONTROL OVER THE ACTIVITIES OF MATERIALLY RESPONSIBLE PERSONS IN THE SCIENTIFIC INSTITUTIONS

2019 ◽  
pp. 160-172
Author(s):  
Ekaterina KOPYLOVA ◽  
Yaroslavna MULYK
Keyword(s):  
Internal Control ◽  
Civil Law ◽  
Causal Link ◽  
The Body ◽  
Legal Responsibility ◽  
Labor Costs ◽  
National Academy Of Sciences ◽  
Control Activity ◽  
Control Functions ◽  
Scientific Institutions

The methodical tools of organization the control over the activities of materially responsible persons in scientific institutions are researched. The functioning of the Institute of Food Resources of the National Academy of Sciences of Ukraine as a co-founder of the Educational, Scientific and Production Complex of "All-Ukrainian Scientific and Educational Consortium" is considered. It is determined that the institute is the leading agency on scientific ensuring of technical and technological progress of food processing industry of Ukraine. The methodical recommendations for organizing the internal control of budget funds managers in their institutions and subordinated budget institutions are considered. It is defined that the basis for the internal control is the responsibility of the manager for control and development of the institution in general. His main tasks are planning and organization of activities; formation of an adequate internal control structure; supervision of implementation of internal control and risk management to make sure that the goal and objectives of the institution are achieved and decisions, including financial ones, will be executed taking into account the principles of legality economy, efficiency, effectiveness and transparency. The concept of the term "responsibility" is considered and the different types of legal responsibility are described. Legal responsibility should be understood as the duty of a person to undergo certain restrictions of state power, provided by law, for the committed offense. The essence of the legal responsibility is as follows: a person, who hasn't executed the responsibility imposed on his/her by law, the new duty is assigned to certain restrictions, negative personal or property consequences. The scientific approaches to the interpretation of the term "material responsibility" are investigated. It is established that the material responsibility can be imposed on any employee who has entered into an employment contract with the owner or the authorized owner of the body. The implementation of labor activities under the civil law contracts is not covered by the sphere of the labor law. Therefore, persons who perform work on the basis of the civil law agreements (for example, under a contract), are responsible for property under the norms of the civil law. The types of material responsibility such as: limited, full, collective (brigade) and increased are considered. The list of grounds for bringing the employee to material responsibility (the presence of the direct harm, violation of the employee or owner of labor duties, causal link between violation and harm, the employee's fault) is studied. The procedure of signing the contract on full material responsibility and indemnity are investigated. The essence of the control over the activities of materially responsible persons is defined. It should be understood as the whole process, which is carried out by the management and employees of the institution, which directed to revealing of deviations and deficiencies in the work of materially responsible persons and bringing the perpetrators to responsibility. The basic directions of improvement of the control over the activity of materially responsible persons in scientific institutions are determined. These can be: the implementation in the institution of the materially responsible people’s instruction, regarding their rights and duties and determining these positions in the job descriptions; the implementation in the institution of the analytical information, where to record the information about the guilty persons, the reasons for the deviations, actions or inactivity of the persons that led to deviations; the formation of a separate subdivision of internal control, which will perform control functions including control over materially responsible persons, or introduction of the position of the internal controller; the computerization of the audit of goods, which will solve such problems as: observance of objectivity, accuracy of results, timing, reduction of labor costs; the development and implementation of a system of internal regulation of the control of the scientific institution, where it is necessary to provide general control questions at the level of the institution, the clearer provisions of internal control which are connected with concrete subjects of its realization, the definition of the rights and duties of persons connected with control activity.

scholarly journals Modification of the method for determining protein solubility of heat treated full-fat soybeans using extraction in potassium hydroxide: Inter-laboratory study

2012 ◽  
pp. 69-78
Author(s):  
Dragan Palic ◽  
Modika Kedibone ◽  
Andre Oelofse ◽  
Marijana Sakac
Keyword(s):  
Heat Treatment ◽  
Potassium Hydroxide ◽  
Nutritional Value ◽  
Protein Solubility ◽  
Official Method ◽  
Good Precision ◽  
Laboratory Methods ◽  
Heat Treated ◽  
Repeatability And Reproducibility ◽  
Growth Trial

Among a number of laboratory methods used to estimate the adequacy of heat treatment applied to full-fat soybean (FFSB) protein solubility in potassium hydroxide (PSKOH) is an unofficial method, but it is used by many laboratories due to its simplicity. It has been reported that the results of PSKOH analysis of the same sample of FFSB on the degree of heat treatment vary widely between laboratories. In this study, the original PSKOH method has been modified and subjected to an inter-laboratory test, with participation of 9 laboratories. Eight FFBS samples were processed by dry extrusion at temperatures ranging from 110 to 164?C and analysed on PSKOH. Processed FFSB samples were also assessed in a growth trial with broilers. Analysis of FFSB by the PSKOH method generated for adequately-processed FFSB values between 67.1 and 76.5%. The values above 76.5% corresponded to under-processed and below 67.1% to over-processed FFSB. The PSKOH method generated good precision, i.e. the repeatability and reproducibility limits of 3.48 and 10.86 %, respectively. The modified PSKOH method can be recommended as a reliable indicator for quality control of heat processed FFSB for the use in routine laboratory practice. This study could pave the way for establishing PSKOH as an official method for determining the nutritional value of FFSB following heat treatment.

scholarly journals Вплив числа електродних пар на похибку електрохімічного давача поляризаційного опору для вимірювання шидкості атмосферної корозії

2020 ◽  
Vol 140 (6) ◽  
pp. 112-124
Author(s):  
С. О. Осадчук ◽  
Л. І. Ниркова ◽  
О. І. Букет
Keyword(s):  
Measurement Error ◽  
Corrosion Rate ◽  
Polarization Resistance ◽  
Sensitive Element ◽  
Aluminum Substrate ◽  
Atmospheric Conditions ◽  
Electrochemical Polarization ◽  
Sensing Element ◽  
Anodized Aluminum ◽  
Tight Contact

Investigate the influence of the number of electrode pairs of multi-electrode co-surface electrochemical polarization resistance sensors on the error of measurement of polarization resistance, and, accordingly, on the corrosion rate under atmospheric conditions. Method of polarization resistance. Determination of the contact area of electrodes with the aluminum substrate by the method of obtaining a print on a flat surface. Graphical modeling of the contact surface of the sensing element from the steel electrodes to the anodized aluminum substrate. Investigation results of the influence of the electrode pairs number of multielectrode cosurface electrochemical polarization resistance sensor, sensing element of which is steel-made and is located on the thermoconductive anodized aluminum substrate, on the measurement error of corrosion rate in atmospheric conditions are presented. It was shown that in determining of the corrosion rate by polarization resistance method the increasing of the electrode pairs number of sensor from one to four increases the reproducibility of measurement results and their convergence with the gravimetric data. Taking into account the form of prints of four-pair sensitive element, the area of surface contact of sensitive element of eight-pair sensor with aluminum substrate was graphically simulated. It was taken into account during modeling, that the design feature of the sensor is a possibility of full contact of one pair of the electrodes with the substrate, which explains the reason of measurement error increasing with increasing the number of electrodes’ pairs. Increasing the pairs number from one to four and then to eight decreases the part of surface of sufficiently tight contact of sensitive element with aluminum substrate from 100% to  50% and further up to 30 %. The extreme dependence of the measurement error on the number of electrodes pairs due to the increasing area of the working surface of the electrodes and reducing the area of tight contact with the aluminum heat-conducting base was revealed. It was found that four electrodes pairs for the presented sensor design is optimal. It was established that the reason of increasing of the error of polarization resistance measurement under atmospheric conditions and, accordingly, the corrosion rate, by using the electrochemical multi-electrode co-surface sensors of polarization resistance under increasing the electrode pairs number (from one to eight) is the decreasing in the surface part of a sufficiently dense contact of the sensitive element (about two or three times). Another tendency that leads to decreasing in error is decreasing in the error of setting the corresponding polarization while increasing the total area of the electrodes. The extreme dependence of this error on the number of electrode pairs with a minimum for a four-pair sensor is shown. The problem of uncontrolled variation of the measurement error by using the polarization resistance sensor of the considered construction was solved and the optimal number of electrode pairs (four) was determined. Using such of a sensor will allow to evaluate the corrosivity of the atmospheric air environment with respect to the responsible metal structures and their corrosion state in local corrosion-dangerous places with stable and minimal error.

Measurement System Analysis of VS Lite

2014 ◽  
Vol 680 ◽  
pp. 447-450
Author(s):  
Ghazirah Mustapha ◽  
M. Saiful Aizat Shafie ◽  
Nur Hayati M. Yahaya ◽  
Jamaluddin Mahmud
Keyword(s):  
Measurement Error ◽  
Total Variation ◽  
Measurement System ◽  
System Analysis ◽  
Measurement System Analysis ◽  
Accuracy Of Measurement ◽  
Repeatability And Reproducibility ◽  
Analysis System ◽  
Replicate Measurements ◽  
User Friendly

Virtual Sensei Lite (VS Lite) is an inexpensive user-friendly motion analysis system. As an alternative motion capture system, it is a must for VS Lite’s user to assess the accuracy of the measurement system capability. To date, such analysis to observe the reliability and accuracy of VS Lite has not been reported. Therefore, this study proposes a procedure for assessing the accuracy and capability of the Virtual Sensei Lite using ANOVA Gage Repeatability and Reproducibility (Gage R&R) designed experiments. In this procedure, a gage R&R study is conducted to obtain replicate measurements on nine parts by three operators. The total variation due to measurement error is then observed to identify the accuracy of measurement. The study able to demonstrate on the accuracy of VS Lite as the value of total variation due to measurement error is within 10%-30%.

scholarly journals Repeatability and Reproducibility of Intraocular Pressure and Dynamic Corneal Response Parameters Assessed by the Corvis ST

2017 ◽  
Vol 2017 ◽  
pp. 1-4 ◽  
Author(s):  
Bernardo T. Lopes ◽  
Cynthia J. Roberts ◽  
Ahmed Elsheikh ◽  
Riccardo Vinciguerra ◽  
Paolo Vinciguerra ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Standard Deviation ◽  
Healthy Volunteers ◽  
Coefficient Of Variation ◽  
Random Order ◽  
Good Precision ◽  
Corvis St ◽  
Deformation Amplitude ◽  
Repeatability And Reproducibility ◽  
Healthy Eyes

Purpose. To assess the repeatability and reproducibility of dynamic corneal response parameters measured by the Corvis ST (Oculus, Wetzlar, Germany). Methods. One eye randomly selected from 32 healthy volunteers was examined by the Corvis ST. Three different devices were used in an alternated random order for taking three measurements at each device in each subject. Standard intraocular pressure (IOP), the biomechanical-compensated IOP (bIOP), and DCR parameters were evaluated. The within-subject standard deviation (ζw) and coefficient of variation (CV) were assessed. Results. Regarding pressure indices, the ζw was below 1 mmHg for repeatability (0.98 for IOP and 0.89 for bIOP) and the CV was 6.6% for IOP and 6.1% for bIOP. For reproducibility, the ζw was around 1 mmHg (1.12 for IOP and 1.05 for bIOP) and the CV was 7.6% for IOP and 7.1% for bIOP. Most of DCR indices presented CV for repeatability below 4%. For reproducibility, the CV of most of the indices were below 6%. The deformation amplitude (DA) ratio in 1 mm and integrated radius were below 4% (1.2% and 3.8%, resp.). Conclusions. The Corvis ST showed good precision (repeatability and reproducibility) for IOP measurements and for DCR in healthy eyes.

scholarly journals Evaluating the International Competitiveness of Vietnam Wood Processing Industry by Combining the Variation Coefficient and the Entropy Method

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 901 ◽  
Author(s):  
Vu ◽  
Tian ◽  
Khan ◽  
Zada ◽  
Zhang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Geographical Location ◽  
International Competitiveness ◽  
Entropy Method ◽  
Variation Coefficient ◽  
Labor Costs ◽  
Total Import ◽  
Processing Industry ◽  
Wood Processing ◽  
Competitiveness Index

Indicators measuring industrial international competitiveness are being continuously improved. However, so far, there is no unified perfect indicator to measure the level of international competitiveness of the industry. Based on the market share index (MS), trade competitiveness index (TC), revealed comparative advantage index (RCA), and relative trade advantage index (RTA), we constructed a comprehensive international competitiveness index by combining the variation coefficient and the entropy method. This study aims to compare and evaluate the international competitiveness of the wood processing industry (ICWPI) in Vietnam using a comprehensive international competitiveness index. The data is collected from the top 22 countries and the total import and export volume of the wood processing industry from the repository of official international trade statistics (UN Comtrade) database for 2001–2017. The results found that it is more accurate to use the combined variation coefficient and the entropy method to evaluate the international competitiveness of the wood processing industry, compared to using only a single index. The growth rate of international competitiveness of Vietnam increased rapidly from 2001 to 2007 but slowed from 2008 to 2017. Vietnam has the advantages of natural resources, low labor costs and favorable geographical location. However, the low productivity gains and added industry value have led to a gradual decline in the international competitiveness growth rate of Vietnam's wood processing industry.

scholarly journals ABOUT SELECTING THE VORTEX FLOWMETER OPTIMAL BLUFF BODY SHAPE

2021 ◽  
pp. 75-81
Author(s):  
Anna Pysarets ◽  
Anastasiia Melnyk ◽  
Olesya Drachuk
Keyword(s):  
Measurement Error ◽  
Sensitive Element ◽  
Body Shape ◽  
Bluff Body ◽  
Geometric Model ◽  
Flow Meter ◽  
Flow Meters ◽  
Flow Rates ◽  
Measured Flow ◽  
Element Shape

Vortex flow meters are becoming more widespread in many industries. This is due to the simplicity and reliability of the flow transducer, the scale linearity, the frequency measuring signal presence, low requirements for alignment and ensuring the straight sections length at the installation site, etc. Among the vortex measuring instruments, the most common are instruments with a bluff body. Such flow meters operation principle is based on measuring the vortex stripping frequency behind a streamlined body installed in the flow. In this case, the metrological characteristics are determined by the bluff body shape. Therefore, the search for the optimal sensing element shape and the hydraulic channel configuration of the flow meter as a whole remains an actual issue. The paper proposes an algorithm for solving this issue according to the criteria of the measured flow rates maximum range and the interaction efficiency of the bluff body with the measured medium flow. The first criterion value is determined from the condition that the Strouhal’s number remains unchanged; the second criterion is based on the estimation of the measured medium pressure drop and the measurement error. To realize the algorithm, simulation modeling is used in the Ansys Fluent fluid simulation software, which uses computational fluid dynamics methods. Modeling carried out for three shapes of the bluff body: a cylinder, a prism with a triangular section, a prism with a trapezoidal section, which made it possible to choose a sensitive element for further solving the multi-parameter optimization problem. Geometric features of the selected sensitive element shape, the limits of their change and boundary values are grounded. The simulation made it possible to estimate the measured flow rates range and pressure losses, as well as to determine the vortex stripping frequency, measurement error and efficiency factor for the investigated geometric model. To further improve the instrument metrological parameters, the authors proposed to supplement the primary transducer geometric model with gradual contraction and diffuser sections. These sections parameters are selected from the conditions of a continuous flow and the maximum measured flow rates range with a minimum pressure loss. The obtained results confirmed the strategy proposed by the authors. The further research prospect is to carry out simulation studies of the flow meter hydraulic channel proposed configuration for different measured media.

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