Computer-Based System For Calibration Of Temperature Transmitter Using Rtd

Using the temperature calibration instrument, the purpose of this paper is to design the uncertainty calculation system. The test was conducted using Resistance Temperature Detector (RTD) sensor, transmitter, and repeated for three times. The data acquisition (DAQ) card is used to interface the temperature instrument and the computer. In order to determine the uncertainty of the temperature measurement, graphical user interface (GUI) software has been developed in Visual Basic(VB) programming language. The developed software shows that the uncertainty of the temperature transmitter measurement can be calculated by interfacing the instrument to the computer through DAQ card. The study focuses on manual temperature measurement and concentrates only on RTD temperature sensor. The results provide the confidence limits of five-point calibration of temperature transmitter that could improve the teaching techniques using computer-based system of the temperature measurement

MEMORANDUM: Calibration of Great Bay Estuary Hydrodynamic Model and Incremental Nitrogen Estimation

This technical memorandum summarizes the completion of the calibration of a hydrodynamic model of the Great Bay Estuary System (GBES) originally started as part of the Squamscott River modeling study. The Squamscott River modeling study was discontinued when it was realized that excessive levels of algae in the Exeter wastewater lagoons discharge had a significant effect on Squamscott River water quality. Because Exeter plans to upgrade its wastewater treatment system and eliminate excessive algal levels in its effluent discharge, it was decided not to develop a hydrodynamic water quality model with Squamscott River water quality data that is so atypical and different than expected future river water quality after the Exeter wastewater treatment system upgrade. However, it was recognized that the completion of the hydrodynamic model of the GBES would provide a useful tool for the cities of Dover, Rochester, and Portsmouth to relate present and future wastewater effluent nitrogen discharges to increases in GBES nitrogen levels. The following is a brief description of the hydrodynamic model framework and calibration analysis against salinity, temperature, and tidal elevation measurements at various locations throughout the GBES. Later sections in this document summarize the application of the GBES calibrated hydrodynamic model in computing incremental nitrogen levels in the Estuary as a result of multiple effluent nitrogen scenarios

The DICE calibration project: design, characterization, and first results

We describe the design, operation, and first results of a photometric calibration project, called DICE (Direct Illumination Calibration Experiment), aiming at achieving precise instrumental calibration of optical telescopes. The heart of DICE is an illumination device composed of 24 narrow-spectrum, high-intensity, light-emitting diodes (LED) chosen to cover the ultraviolet-to-near-infrared spectral range. It implements a point-like source placed at a finite distance from the telescope entrance pupil, yielding a flat field illumination that covers the entire field of view of the imager. The purpose of this system is to perform a lightweight routine monitoring of the imager passbands with a precision better than 5 per-mil on the relative passband normalisations and about 3{\AA} on the filter cutoff positions. The light source is calibrated on a spectrophotometric bench. As our fundamental metrology standard, we use a photodiode calibrated at NIST. The radiant intensity of each beam is mapped, and spectra are measured for each LED. All measurements are conducted at temperatures ranging from 0{\deg}C to 25{\deg}C in order to study the temperature dependence of the system. The photometric and spectroscopic measurements are combined into a model that predicts the spectral intensity of the source as a function of temperature. We find that the calibration beams are stable at the $10^{-4}$ level -- after taking the slight temperature dependence of the LED emission properties into account. We show that the spectral intensity of the source can be characterised with a precision of 3{\AA} in wavelength. In flux, we reach an accuracy of about 0.2-0.5% depending on how we understand the off-diagonal terms of the error budget affecting the calibration of the NIST photodiode. With a routine 60-mn calibration program, the apparatus is able to constrain the passbands at the targeted precision levels.Comment: 25 pages, 27 figures, accepted for publication in A&

Optical power model of a laser bar diode

This article proposes a modelling method for laser diodes optical output power including its dependency on temperature. The device used for this study is a 40 W Monocrom's diode, with 808 nm wavelength emitted light and with a 19 emitters CS mount laser bar, mounted using the patented Monocrom's clamping method. The aim of this study is to propose a Pspice modelling of the laser diode device, mainly focusing in the optical output power variation with the temperature and allowing its computer simulation. Also to setup a characterization system to obtain the necessary parameters values for the optical model mathematical expressions. Therefore, the article explains the proposed method for the optical output power model generation of the laser bar diode and how its parameters values are obtained, an optical output power measurement setup and its calibration, the obtained Pspice model and its simulation, and the characterization system that allows to obtain the necessary parameters with short rise up time current slopes. Finally, evaluation of results and related conclusions are exposed.Peer ReviewedPostprint (author's final draft

Geometric calibration of focused light field camera for 3-D flame temperature measurement

Focused light field camera can be used to measure three-dimensional (3-D) temperature field of a flame because of its ability to record intensity and direction information of each ray from flame simultaneously. This work aims to develop a suitable geometric calibration method of focused light field camera for 3-D flame temperature measurement. A modified method based on Zhang's camera calibration is developed to calibrate the camera and the measurement system. A single focused light-field camera is used to capture images of bespoke calibration board for calibration in this study. Geometric parameters including intrinsic (i.e., camera parameters) and extrinsic (i.e., camera connecting with the calibration board) of the focused light field camera are calibrated to trace the ray projecting onto each pixel on CCD (charge-coupled device) sensor. Instead of using line features, corner point features are directly utilized for the calibration. The characteristics of focused light field camera including one 3-D point corresponding to several image points and matching main lens and microlens f-numbers, are used for calibration. Results with a focused light field camera are presented and discussed. Preliminary 3-D temperature distribution of a flame is also investigated and presented

The table mountain 8-mm-wavelength interferometer

The system components, performance, and calibration of two element radio interferometer operating at 8.33 mm wavelength are discussed. The interferometer employs a 5.5 m and a 3 m diameter antenna on an east-west baseline of 60 or 120 m, yielding fringe spacings at transit of 28 or 14 in. respectively. The broad intermediate frequency bandpass of 100 to 350 MHz and the system noise temperature of 500 K provide high sensitivity for the measurement of continuum sources. The interferometer has been used for high resolution studies of the planets and the Sun, and it is currently being adapted to study solar flare emissions at high spatial and time resolution

An empirical temperature calibration for the Delta a photometric system. II. The A-type and mid F-type star

With the Delta a photometric system, it is possible to study very distant galactic and even extragalactic clusters with a high level of accuracy. This can be done with a classical color-magnitude diagram and appropriate isochrones. The new calibration presented in this paper is a powerful extension. For open clusters, the reddening is straightforward for an estimation via Isochrone fitting and is needed in order to calculate the reddening-free, temperature sensitive, index (g1-y)0. As a last step, the calibration can be applied to individual stars. Because no a-priori reddening-free photometric parameters are available for the investigated spectral range, we have applied the dereddening calibrations of the Stromgren uvbybeta system and compared them with extinction models for the Milky Way. As expected from the sample of bright stars, the extinction is negligible for almost all objects. As a next step, already established calibrations within the Stromgren uvbybeta, Geneva 7-color, and Johnson UBV systems were applied to a sample of 282 normal stars to derive a polynomial fit of the third degree for the averaged effective temperatures to the individual (g1-y)0 values with a mean of the error for the whole sample of Delta T(eff) is 134K, which is lower than the value in Paper I for hotter stars. No statistically significant effect of the rotational velocity on the precision of the calibration was found.Comment: 5 pages, 2 figures, accepted by A&

Infrared Imagery of Shuttle (IRIS). Task 2, summary report

End-to-end tests of a 16 element indium antimonide sensor array and 10 channels of associated electronic signal processing were completed. Quantitative data were gathered on system responsivity, frequency response, noise, stray capacitance effects, and sensor paralleling. These tests verify that the temperature accuracies, predicted in the Task 1 study, can be obtained with a very carefully designed electro-optical flight system. Pre-flight and inflight calibration of a high quality are mandatory to obtain these accuracies. Also, optical crosstalk in the array-dewar assembly must be carefully eliminated by its design. Tests of the scaled up tracking system reticle also demonstrate that the predicted tracking system accuracies can be met in the flight system. In addition, improvements in the reticle pattern and electronics are possible, which will reduce the complexity of the flight system and increase tracking accuracy

Calibrating whole building energy model: a case study using BEMS data

This paper describes a Calibration methodology which is specifically configured to best match actual building performance, based on a case study conducted to calibrate whole building energy model using Building Energy Management System (BEMS) measured data. It details the calibration approach which was designed to meet the specific characteristic of the spaces, systems and energy use in the pilot school building. Two calibration methods were developed; one is for electrical and the other is for thermal energy along with calibrated weather file. The result shows excellent correlation with the measured electricity and room air temperature and demonstrates the effectiveness of the methodology. Mean Bias Error (MBE) and Cumulative Variation of Root Mean Squared Error (CVRMSE) for electricity consumption is 6% and 14% respectively and -5 and 7% for air temperature