scholarly journals The calibration and uncertainty evaluation by elementary measurement models

2021 ◽  
Vol 1 ◽  
pp. 1-10
Author(s):  
Oleksandr Samoilenko

Nature has often made necessary things simple (elementary) and complicated ones unnecessary. This can be applied to measurement models of the large amount of working measurement standards and working measuring instruments. Nevertheless, if measurement model is elementary, it does not mean that it is primitive. It should be formulated according to the sufficiency, mathematical completeness and correctness principles. The attempt to formulate models according to the mentioned principles is introduced. Models are called elementary, as measurement result is function of one or two homogeneous measured quantities. Thus, measurement result is a single reading of the measurement standard or measuring instrument or average value of several readings, or bias as the disparity between readings of the calibrated measuring instrument and measurement standard. Notwithstanding the elementary measurement models simplicity, many variants of solutions are obtained in the process of the measurement result uncertainty evaluation by these models. Publication demonstrates how to choose the best uncertainty evaluation from many variants of solutions depending on whether single readings or average of several readings is included to measurement model. The best choice of the measurement model depends on resolution of the indicating measuring instrument. Moreover, the best choice depends on the measurement standard used for calibration, which is material measure or measuring instrument and depends on the calibration object: material measure or measuring instrument.

2020 ◽  
Vol 3 (2) ◽  
pp. 28-31
Author(s):  
Azhari Jum’atullah ◽  
Irzan Zakir ◽  
Massus Subekti

The purpose of this research is to get the strong value of lighting at L1 building of Universitas Negeri Jakarta and compare the measurement result using luxmeter with software of Dialux Evo 6.2. This research uses engineering methods by utilizing three ways of measurement, manual calculation and simulation of Dialux Evo 6.2. Measurement method using Luxmeter as measuring instrument to get the measured value of the measured light in the learning room based on the standard procedure of calculation according to SNI and the simulation using the program of Dialux Evo 6.2 to predict the strong value of the illumination that should be in the building. The results of this study indicate that the average value of the average light is still not much according to the standard. Then by manual calculation and simulation, the strong value of illumination that should be in the building is also below 350 lux for study room, under 500 lux for laboratory, and under 750 lux for technic al drawing room. Then to improve the design of the high rise building, to achieve a strong value of lighting above 350 lux, 500 lux and 750 lux can be obtained by changing the wall color characters that increased to reach 3- 9.6 percent, a 52-84 percent increase after changing the point of light , as well as an increase of 54-85 percent after changing the color of the walls and the point of light. Abstrak Tujuan dari penelitian ini adalah untuk mendapatkan nilai kuat penerangan pada gedung L1 Universitas Negeri Jakarta dan membandingkan hasil pengukuran menggunakan luxmeter dengan software Dialux Evo 6.2. Penelitian ini  menggunakan metode rekayasa teknik dengan memanfaatkan tiga cara yaitu pengukuran, perhitungan manual dan simulasi Dialux Evo 6.2. Cara pengukuran menggunakan Luxmeter sebagai alat ukur untuk mendapatkan nilai kuat penerangan yang terukur pada ruang belajar berdasarkan standar tata cara perhitungan menurut SNI dan cara simulasi menggunakan program Dialux Evo 6.2 untuk memprediksi nilai kuat penerangan yang seharusnya terdapat pada gedung bertingkat. Hasil penelitian ini menunjukan bahwa nilai kuat penerangan rata-rata yang masih banyak yang belum sesuai standar. Kemudian dengan cara perhitungan manual dan simulasi, nilai kuat penerangan yang seharusnya terdapat pada gedung bertingkat tersebut juga masih dibawah 350 lux untuk ruang belajar, dibawah 500 lux untuk laboratorium, dan dibawah 750 lux untuk ruang gambar teknik. Kemudian pada perbaikan desain gedung bertingkat tersebut, untuk mencapai nilai kuat penerangan di atas 350 lux, 500 lux dan 750 lux dapat diperoleh dengan merubah karakter warna dinding yang mengalami kenaikan mencapai 3-9,6 persen, kenaikan 52-84 persen setalah merubah titik lampu, serta kenaikan 54-85 persen setelah merubah warna dinding dan titik lampu.


TAMAN VOKASI ◽  
2017 ◽  
Vol 5 (1) ◽  
pp. 31
Author(s):  
Tri Puji Prianto

This study aims to determine the improvement of learning outcomes of mechanical measuring tools using the discussion method macromedia flash class X students SMK Ma'arif NU 1 Salam Magelang. The data collection technique uses test questions to measure initial capability and tests to measure learning of mechanical measuring instruments. The result of the research shows that (1) The use of macromedia flash discussion method influences the learning result of mechanical measuring instrument from t test with t value (0.000) smaller than t table value (0,025). (2) Based on the result of the test before and after the treatments the average score of learning result of mechanical measuring instrument increased by 10.77 points which was originally 72,01 to 82,78 and all values above KKM (Criteria Completed Minimum). (3) the average value in the treatment class is greater than the control class with the selisis of 6.89 points. It can be concluded that the macromedia flash discussion method can improve the learning outcomes of mechanical measuring instruments


Humaniora ◽  
2016 ◽  
Vol 7 (2) ◽  
pp. 211
Author(s):  
Antonina Pantja Juni Wulandari

Article described resilient and competitive characters of Senior High School students in Jakarta. This research used the descriptive quantitative research methodology. The population in this research was taken from class 12 students of Senior High School in Jakarta. The sample-taking technique used non-probability sampling. The data collection used the questionnaires given to Senior High School students around Jakarta. The questionnaire consists of two psychological measuring instruments, namely resilient and competitive characters. The measuring instrument for the resilient character was taken from the resilience theory, Resilience Scale (RS), which was developed by Wagnild and Young. The measuring instrument for the competitive character was taken from the achievement motivation theory that is the motivation to encourage a person to be successful in competition with a standard of excellence. Based on the result of this research, the average value of the resilient character is 2.98, while the average value of the competitive character is 2.92. The largest resilient character category is in the high category with the percentage of 59%, while the largest competitive category is in the high category with 224 students and the percentage of 58%. The suggestion for the school is that the teaching of resilient and competitive characters can be presented in the example, definition, discussion, and role-playing. The suggestion for the teacher is to give rewards for students with good characters. The reward is not only for the achievement, but students with good character should be praised to maintain their behavior and use it as the model for other students. The suggestion for the next researcher is that the qualitative research can be used to observe resilient and competitive character from family or school. 


2018 ◽  
pp. 76-84
Author(s):  
K. V. Sorokin ◽  
E. A. Sunarchina

Improvement of orbits precision is one of the most important tasks of space surveillance catalogue maintenance. The solution of this problem is directly related to an adequate consideration of the errors of the coordinate information from the measuring instruments. The article consideresd a new method for estimating the precision of measuring instruments on the catalog orbits. To carry out such analysis, in PJSC «VIMPEL» special technological program was created. Main results of a study of radar errors with orbits of space surveillance catalogue was presented. Also, the results were compared with data of measuring instrument's calibration software complex. This software complex provides determination of satellite's position with errors less than 10 m. A new dynamic model of measuring instrument errors is proposed.


Assessment ◽  
2021 ◽  
pp. 107319112199876
Author(s):  
Shalom H. Schwartz ◽  
Jan Cieciuch

Researchers around the world are applying the recently revised Portrait Value Questionnaire (PVQ-RR) to measure the 19 values in Schwartz’s refined values theory. We assessed the internal reliability, circular structure, measurement model, and measurement invariance of values measured by this questionnaire across 49 cultural groups ( N = 53,472) and 32 language versions. The PVQ-RR reliably measured 15 of the 19 values in the vast majority of groups and two others in most groups. The fit of the theory-based measurement models supported the differentiation of almost all values in every cultural group. Almost all values were measured invariantly across groups at the configural and metric level. A multidimensional scaling analysis revealed that the PVQ-RR perfectly reproduced the theorized order of the 19 values around the circle across groups. The current study established the PVQ-RR as a sound instrument to measure and to compare the hierarchies and correlates of values across cultures.


2014 ◽  
Vol 14 (2) ◽  
pp. 229-244 ◽  
Author(s):  
Ali Mohammed Alashwal ◽  
Hamzah Abdul-Rahman

Purpose – The purpose of this paper is to determine the measurement constructs of learning within construction projects' milieu. The literature indicated some mechanisms of learning in projects under four aspects, namely knowledge sharing, knowledge creation, team action to learn, and learning support. The empirical study attempts to verify whether intra-project learning can be measured through these aspects. Design/methodology/approach – The study used a survey method to collect the data from 36 mega-sized building projects in Malaysia. In total, 203 questionnaires were collected from professionals working in the sites of these projects. The data were analysed using principal component analysis (PCA) to determine the constructs of intra-project learning. Partial least squares-path modeling was used then to confirm the results of PCA and determine the contribution of each construct to intra-project learning. Findings – The results affirmed two constructs of intra-project learning, named, social and technical and each consisted of four indicators of learning. Originality/value – The paper emphasized the socio-technical perspective of learning and contributed to developing a hierarchical measurement model of learning in construction project. A project manager can propose new initiatives in response to the new perspective of learning for team building and continuous development. Lastly, the paper provides a comprehensive presentation of how to estimate the hierarchical measurement models of project learning as a latent variable.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3537
Author(s):  
Christian Friedrich ◽  
Steffen Ihlenfeldt

Integrated single-axis force sensors allow an accurate and cost-efficient force measurement in 6 degrees of freedom for hexapod structures and kinematics. Depending on the sensor placement, the measurement is affected by internal forces that need to be compensated for by a measurement model. Since the parameters of the model can change during machine usage, a fast and easy calibration procedure is requested. This work studies parameter identification procedures for force measurement models on the example of a rigid hexapod-based end-effector. First, measurement and identification models are presented and parameter sensitivities are analysed. Next, two excitation strategies are applied and discussed: identification from quasi-static poses and identification from accelerated continuous trajectories. Both poses and trajectories are optimized by different criteria and evaluated in comparison. Finally, the procedures are validated by experimental studies with reference payloads. In conclusion, both strategies allow accurate parameter identification within a fast procedure in an operational machine state.


Author(s):  
Alexandros Christos Chasoglou ◽  
Panagiotis Tsirikoglou ◽  
Anestis I Kalfas ◽  
Reza S Abhari

Abstract In the present study, an adaptive randomized Quasi Monte Carlo methodology is presented, combining Stein’s two-stage adaptive scheme and Low Discrepancy Sobol sequences. The method is used for the propagation and calculation of uncertainties related to aerodynamic pneumatic probes and high frequency fast response aerodynamic probes (FRAP). The proposed methodology allows the fast and accurate, in a probabilistic sense, calculation of uncertainties, ensuring that the total number of Monte Carlo (MC) trials is kept low based on the desired numerical accuracy. Thus, this method is well-suited for aerodynamic pressure probes, where multiple points are evaluated in their calibration space. Complete and detailed measurement models are presented for both a pneumatic probe and FRAP. The models are segregated in sub-problems allowing the evaluation and inspection of intermediate steps of MC in a transparent manner, also enabling the calculation of the relative contributions of the elemental uncertainties on the measured quantities. Various, commonly used sampling techniques for MC simulation and different adaptive MC schemes are compared, using both theoretical toy distributions and actual examples from aerodynamic probes' measurement models. The robustness of Stein's two-stage scheme is demonstrated even in cases when signiffcant deviation from normality is observed in the underlying distribution of the output of the MC. With regards to FRAP, two issues related to piezo-resistive sensors are addressed, namely temperature dependent pressure hysteresis and temporal sensor drift, and their uncertainties are accounted for in the measurement model. These effects are the most dominant factors, affecting all flow quantities' uncertainties, with signiffcance that varies mainly with Mach and operating temperature. This work highlights the need to construct accurate and detailed measurement models for aerodynamic probes, that otherwise will result in signiffcant underestimation (in most cases in excess of 50%) of the final uncertainties.


2021 ◽  
pp. 9-15
Author(s):  
Sergey F. Levin

The problem of calibration of measuring instruments for given conditions based on the correction function is considered as a measurement problem of structural-parametric identification of the calibration diagram. It is shown, that the correction function allows at the first stage to obtain a ratio for correcting the readings, and at the second stage to obtain a corrected measurement result, it is necessary to identify the probability distribution of possible deviations from it. An example of solving the measurement problem of calibration for given conditions is given. Negative aspects of the practice of calibration of measuring instruments are noted: carrying out calibration under normal conditions according to the methods of verification of measuring instruments; presentation of calibration results by tables of joint readings of measuring instruments and standards; the presence in the calculations of the calibration diagram of significant restrictions on the mathematical apparatus of the «Guidelines for the expression of measurement uncertainty», specified by ISO/IEC 31010:2019 “Risk management – Risk assessment techniques”.


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