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The aim of the work is to improve the methods of determining the standby time of transit recycling wagons at the sorting station. Systems analysis, analytical, graphical modeling, Ishikawi scheme and methods of comparing the performance of transit and local carriages were used. The reasons for the extra time lost by the wagons at the railway stations were given. Methods of adjusting the stopping time of wagons at the sorting station and their advantages, disadvantages and error rates were studied. The options and time costs of moving the wagon from one loading to the unloading location were analyzed, and the negative factors that cause the wagons to be overstayed at the sorting station were identified. In order to increase the level of performance of the sorting station performance and speed up the delivery of goods, a four-step method of reasonable standardization of the stopping time of wagons was recommended. This method allows you to analyze the time spent on each operation of the wagon on the road, to identify and eliminate inefficient time losses in a timely manner, to identify negative factors and increase the accuracy of standardization methods by 5-10%.

The small-strain shear modulus of soils and rocks is an important input parameter in geotechnical analyses. Its estimation using the resonant column apparatus relies on accurate knowledge of the rotational inertia of the apparatus’s active end. Due to the complex geometry of the active end, its inertia is typically found from a calibration exercise. In this study a range of aluminium calibration bars and steel masses were used to compare two different calibration exercises presented in the literature. The resulting values of active end inertia are shown to be highly method-dependent. The method of compensating for the drive connection stiffness by finding the apparatus resonant frequency is found to introduce errors at low stiffness. The combined use of calibration bars and masses reduces scatter but yields poor results for stiff bars. An alternative approach to mitigate both of these problems is suggested. Active end inertia is found to be constant using this alternative approach. While effects of base inertia and reaction mass inertia are found to be small for this apparatus, compliance of the drive system is shown to significantly reduce resonant frequencies at high stiffnesses which increases the apparent active end inertia. This reduction in resonant frequency is modelled and used to derive frequency correction factors, which reduce errors in shear modulus to within acceptable limits when using the constant value of active end inertia. This demonstrates the potential for increasing the limit of sample stiffness where sufficient calibration data are available.

The Distinct element method (DEM) is a promising approach to model the microscopic behaviour of granular materials, but the capability of the simulations to reproduce the mechanical response of real granular materials depends strongly on the contact model parameters utilized. The present study focuses on the calibration and validation of the rolling resistance linear model parameters for Cuxhaven sand based on the experimental results from triaxial and oedometer tests. A sensitivity analysis was conducted to explore the influence of contact model parameters on the sample preparation and the shear stage of triaxial tests. The influence of parameters like rolling resistance friction coefficient, inter-particle friction coefficient, effective modulus, and normal-to-shear stiffness ratio were investigated. For calibration of the DEM model, the input parameters were selected such that the simulations reproduce the macro mechanical characteristics like dilation angle, peak stress, and stiffness. The calibrated parameters were then validated by simulating a one-dimensional compression test. The results are in good agreement with the experiments, which proves the suitability of the calibrated parameters. In addition, the validated parameters were applied to investigate the mechanical behaviour including the evolution of contact force chains, non-coaxiality of principal stress and strain rate, and sample inhomogeneity during a simple shear test.

This paper presents a novel methodology for calibrating cup anemometers, addressing a critical need in the wind energy sector for accurate and reliable wind speed measurement. Ensuring measurement accuracy through calibration remains a major challenge. In response, a cost-effective alternative methodology is presented that takes advantage of statistical analysis techniques. York linear regression is applied for the estimation of calibration coefficients, a novelty in the context of cup anemometer calibration. The approach overcomes the limitations of traditional procedures reliant on wind tunnel facilities. Experimental validation of the proposed methodology, carried out with wind turbines placed at a height of 10 meters, demonstrates that a reliable calibration can be achieved even in sites with a low wind regime.

The measurement of response time of pulse oximeter lacks standardized method and proper thresholds and alternative measurement methods are needed to minimize error and improve efficiency in calibration method of pulse oximeter due to the increasing number of pulse oximeter variations distributed due to the covid 19 pandemic. This study aims to measure the Response Time (RT) of a finger pulse oximeter with 6 different types of conditioning to determine the RT mean and standard deviation in order to classify the pulse oximeter based on their types. We evaluated the response time of 50 finger pulse oximeters (20 patient monitor type, 8 handheld type, and 22 fingertip type) using 6 saturation and desaturation conditioning methods with a SpO2 Simulator. Quantitative analysis used to determine the initial threshold value. From 50 pulse oximeters found the fastest response pulse oximeter are fingertip type with mean time are 9.71 seconds and the most stable of each conditioning pulse oximeter are patient monitor type with the average RT 3.47 seconds, and Handheld type are put in the middle. With the conclusion that Patient monitor type are classified in monitoring class, Handheld type are classified both in monitoring and diagnostic class and Fingertip both classified in diagnostic and preventive class.

Mobile Terrestrial LiDAR (Light Detecting And Ranging) (MTL) is a new technology adapted to increasing need of 3D geo-referenced data. The system requires an integration of laser scanners with other sensors of navigation such as GPS and INS and inertial measurement unit. This fusion allows direct georeferencing of point cloud data. As well as the practical accuracy, the theoretical accuracy of raw data also deals with the investors in the mobile mapping systems. This study evaluates the theoretical accuracy of point clouds produced by MTL system through the error propagation theory. The accuracy estimation implies a description of sensors integration, synchronization and calibration. In addition, this paper presents models of reference transformation. The results of this study show that the MTL data accuracy depends on several parameters. Among these parameters, the range is the most critical one.

Wheat growth simulation using crop models: a review of methods, and their potential and limitations. Crop models describe the growth and development of a crop interacting with its surrounding agro-environmental conditions (soil, climate and the close conditions of the plant). However, the implementation of such models remains difficult because of the high number of explanatory variables and parameters. It often happens that important discrepancies appear between measured and simulated values. This article aims to highlight the different sources of uncertainty related to the use of crop models, as well as the actual methods that allow a compensation for or, at least, a consideration of these sources of error during analysis of the model results. This article presents a literature review, which firstly synthesises the general mathematical structure of crop models. The main criteria for evaluating crop models are then described. Finally, several methods used for improving models are given. Parameter estimation methods, including frequentist and Bayesian approaches, are presented and data assimilation methods are reviewed.

Hydrogen isclassified as New Energy and also considered as the most promising transportation fuel candidate in the future. Various pilots test of hydrogen fuel cell vehicles by the world's leading automotive industries since the last 50 years have begun to show bright spot in the utilization of hydrogen-based fuel cells as vehicle fuel. The electrolysis process of water (H2O) would produce H2 (hydrogen) and O2 (oxygen). The conventional method resulted in inconsistent volume and quality of HHO gas. However, the current development of HHO gas production through electrolysis process varies in term of materials, production process, design of certain tools, and technical modifications to obtain optimum results. In this research, the Hybrid Multistack TypeHHO generator has been designed and developed by combining two types of dry and wet cell generators. In this study using both cell type generator (wet and dry cell) or called as a hybrid type. Through the process of electrolysis in HHO enclosure space, the HHO gas was produced. The volume of HHO gas obtained from the HHO generator as an alternative fuel is strongly influenced by the electrical current supplied and the concentration of KOH catalyst used. The test was conducted with four stages of catalyst amount from 5.6g/L; 11.2g/L; 16.8g/L; and 22.4g/L. The applied current is linearly increased, with the increasing HHO gas production. It is proven when with the amount of catalyst used at 22.4g/L, the average HHO gas produced is 230.3mL/min. The author analyzes the performance of the generator in term of current and HHO gas production at a predetermined 12V constant voltage.

The main function of the cooling system is to control the temperature of the engine components and improve the performance of an engine. To know the flow and temperature distribution in the jacket cooling system for 6 cylinder diesel engine is analyzed using 1 dimensional method by using GT-Suite 1D simulation software package. The present work employs 1D simulation of water jacket in GT-ISE to perform a comprehensive study of mass-flow and thermal distribution over the inlet of the cooling package of a selected engine in several steady state operating points. The results show, that the suggested predictive method successfully captures the thermal effect of recirculation while reducing the necessity for calibration done by prototype testing.

pH and electrolytic conductivity are important metrological quantities for several areas of industry. To get reliable results it is necessary to calibrate measuring instruments and devices regularly. For this purpose certified reference solutions are needed. DKD-K-06901 is a manufacturer of certified reference solutions and offers calibration services in the field of analytical chemistry. There are three accredited calibration procedures for the determination of pH used by ZKM - ANALYTIK - GmbH. A new calibration procedure for electrolytic conductivity was established by experts in DKD-K-06901 as the result of a development project in cooperation with National Metrology Institutes. The validation of all procedures is guaranteed by the participation in national and international comparison measurements. Furthermore DKD-K-06901 is actively involved in the work of technical and standardisation committees for developments of analytical quantities.

In today's economy goods and information are being exchanged globally, international travel is commonplace as is the cross-boarder transport of livestock and agricultural products, and this trend is set to continue. Just as important are issues that impinge on our quality of life, such as health care, the environment and food quality. A strong international measurement and standards infrastructure is critical to assure equity in trade and a high quality of life, by ensuring that products and services meet their specifications. In the field of chemical measurements, certified reference materials (CRMs), measurement standards and reference measurement results provide stated references upon which analytical laboratories can anchor their measurement results. The traceability of measurement results to internationally accepted stated references, together with their stated measurement uncertainties, as described in ISO/IEC 17025, provides the basis for their comparability and global acceptance. Recent global activities which are succeeding in developing a system for the international acceptance of chemical measurements are described, notably: activities of the National Metrology Institutes and the BIPM; the Mutual Recognition Arrangement of the International Committee of Weights and Measures (CIPM MRA) for National Calibration Certificates and Measurement Capabilities; the Inter-Laboratory Comparisons organised through the working groups of the Consultative Committee for Amount of Substance – Metrology in Chemistry (CCQM), and the activities of the Joint Committee for Traceability in Laboratory Medicine (JCTLM).

As part of a national quality assurance programme of the Cercl'Air in cooperation with the Swiss Federal Office for the Environment (FOEN) and the Swiss Federal Office of Metrology (METAS) there have been intercomparisons of air quality monitoring stations of interested institutions in regular intervals since 1988. The former approach, alternating between calibrations with test gases of measuring stations on site and gathering mobile measuring units for additional comparative measurements every second year, had to be modified as mobile measuring stations have become increasingly sparse over the last years. The idea was to find a solution to combine the two types of intercomparison in one campaign. The problem was solved by assembling a mobile reference station for measuring air pollution, with the addition of equipment to provide test gases for the candidate instruments. With this mobile measuring unit, calibration with test gases and comparative measurements could be performed on site at the candidate air pollution monitoring stations. The results of the 2007 intercomparison campaign showed that the achieved quality improvements in air pollution measurements over the last twenty years – decrease of expanded uncertainties in intercomparisons by a factor of 4 to 7 depending on the type of pollutant – could be sustained.

High-quality and long-term comparable time series of the relevant atmospheric observations are the essential prerequisite to understand the dynamical, physical and chemical state of the atmosphere from seasonal to multi-decadal time scales. For relevant gaseous compounds such as ozone, methane (CH4) and carbon monoxide (CO), the requirements are secured by tracing back these observations to common primary standards. Periodical audits of the system in operation and the performance of measurement sites provide additional information about data quality and comparability. The results of 48 audits conducted by the World Calibration Centre for Surface Ozone, Carbon Monoxide and Methane (WCC-Empa) at global stations of the Global Atmosphere Watch programme (GAW) from 1996 to 2009 show that most of the audited sites meet the data quality objectives for ozone and methane whereas the situation is less uniform for carbon monoxide.

Knowledge of evapotranspiration (ET) is very important for water resources planning and management. Several methods have been developed to estimate ET. Among them the PENMAN-MONTEITH method is recommended by the Food and Agriculture Organization as a reference method. However, its use is difficult in some areas particularly in developing countries where climate data are not always available. One of the alternatives is then to use methods integrating fewer climatic variables. This study aims to evaluate alternative evapotranspiration methods and to calibrate and validate the two best ones. Daily climate data (Tmax, Tmin, Sr, RHmax, RHmin and u2) of eight stations from 1998 to 2012 were used. Each of the twenty models was compared to evaluate ET0 estimated by the PENMAN-MONTEITH by determining different statistical indices. The results show that the methods of H.L. PENMAN (1963), W. ABTEW (1996), J.D. VALIANTZAS 1 and 3 (2012-a, 2012-b) and G.H. HARGREAVES (1975) have given the best estimations of the evapotranspiration. Among these five methods, the two best are retained for calibration and validation. After calibration, the PENMAN method logically provides the best estimation of reference evapotranspiration, in front of that of ABTEW.