DIAL Instrument Research Articles

Computer Vision-Based Method for Digitizing the Surface of the Dial Instrument and Tracking the Pointer’s Movement

Using the dial instrument for reading the oxygen pressure in the medical environment demands monitoring the pointer’s movement and keeping track of its readings. Usually, the monitoring task is done by the administrator in the medical facilities. To ensure real time and accurate monitoring, the administrator must be supported by vision-based advanced methods to digitize the surface of the dial instrument and to track the pointer’s movement. In this paper, a method is proposed to localize the three main references in the dial instrument, namely Pointer, FULL indicator, and EMPTY indicator. Once these references have been precisely determined, the proposed method records the status of the dial instrument. An emergency alert must be triggered while the pointer is moved toward the EMPTY area. Different computer vision techniques have been developed to implement the digitizing and monitoring in terms of real time constraint. The proposed method has been experimentally verified over 750 frames while the dial instrument was run and monitored the oxygen pressure. The obtained result unveil that the average running time is 0.316 s. The detection accuracy of the proposed method for these reference indicators varied from 88.5% to 100% over the first 30 frames of the tested video streams. Since the proposed method has been developed to keep track for the pointer’s movement, it can recover the detection failure while dial instrument is running. Moreover, the proposed method can overcome the reading error of the pointer’s centre point compared to the Hough transform method. Compared with the development of the Hough transform, the proposed method distinguishes itself by successfully employing morphological operations and color space processing to highlight region of interest, regardless of its high intensity values. In context of the applications of the pointer extraction of the dial instrument, another comparison has been conducted for the proposed method. The latter distinguished itself by digitizing the surface of the dial instrument without using the neural network mechanism; offering a recovery of the failure detection, and employing the idea of the black-white mask to concentrate the proposed method’s developments.

Development of the Renaissance Diptych Dial Instrument

Time is the dividing line between an event's beginning and end. Humans have been keeping track of time in ways that have evolved since the beginning of time. Utilizing the sun's shadow is the strategy that is still in use today. Western countries went through the Renaissance after the Middle Ages, which was a period of resurgence in science. There were several astronomical instruments discovered, and the Diptych Dial is one of them. Because it differs from the sundials that generally evolve, this device is quite intriguing. It can be used to determine the moon phase, time, direction, and several other things by using two regions of the dial. Additionally, because of its attractive appearance, it can be used as decoration or a collection. It can be used to determine the moon phase, the time, the direction, and can also be used as decoration or a collection due to its attractive shape, which has artistic value, by using two areas of the dial. The purpose of this study is to determine how the Diptych Dial instrument changed over the course of the Renaissance. using descriptive analytic and qualitative research techniques. The development of Diptych Dial instruments during the Renaissance was quite rapid, as evidenced by the number of Diptych Dials produced, which reached thousands in the city of Nuremburg, and their distribution to various European regions. Data from several previous studies and a collection of museum collections were used as data sources.

Atmospheric CO2 measurements with a 2-μm DIAL instrument

We report on ground-based atmospheric concentration measurements of carbon dioxide, using a pulsed direct detection differential absorption lidar operating at 2051 nm. The transmitter is based on a tunable parametric source emitting 10-mJ energy, 10-ns duration Fourier-limited pulses. Range resolved concentration measurements have been carried out on the aerosol back-scattered signal. Cloud signals have been used to get long range integrated-path measurements.

New capability for ozone dial profiling measurements in the troposphere and lower stratosphere from aircraft

Recently, we successfully demonstrated a new compact and robust ozone DIAL lidar for smaller aircraft such as the NASA B200 and the ER-2 high-altitude aircraft. This is the first NASA airborne lidar to incorporate advanced solid-state lasers to produce the required power at the required ultraviolet wavelengths, and is compact and robust enough to operate nearly autonomously on the high-altitude ER-2 aircraft. This technology development resulted in the first new NASA airborne ozone DIAL instrument in more than 15 years. The combined ozone, aerosol, and clouds measurements provide valuable information on the chemistry, radiation, and dynamics of the atmosphere. In particular, from the ER-2 it offers a unique capability to study the upper troposphere and lower stratosphere.

Simultaneous remote monitoring of atmospheric methane and water vapor using an integrated path DIAL instrument based on a widely tunable optical parametric source

We report on the remote sensing capability of an integrated path differential absorption lidar (IPDIAL) instrument, for multi-species gas detection and monitoring in the 3.3-3.7 µm range. This instrument is based on an optical parametric source composed of a master oscillator-power amplifier scheme--whose core building block is a nested cavity optical parametric oscillator--emitting up to 10 µJ at 3.3 µm. Optical pumping is realized with an innovative single-frequency, 2-kHz repetition rate, nanosecond microchip laser, amplified up to 200 µJ per pulse in a single-crystal fiber amplifier. Simultaneous monitoring of mean atmospheric water vapor and methane concentrations was performed over several days by use of a topographic target, and water vapor concentration measurements show good agreement compared with an in situ hygrometer measurement. Performances of the IPDIAL instrument are assessed in terms of concentration measurement uncertainties and maximum remote achievable range.

Dial Instrument Calibration by both Automatic and Half-Automatic Methods

This paper presents a calibration system by video processing technique. The system can calibrate large number of different types of dial instruments. The system is composed of an automatic recog-nition approach and a half-automatic approach. Both the automatic calibration and half-automatic calibration include four steps: 1st, dial plane circle edge extraction and center identification; 2nd, pointer extraction; 3rd, scale start and end position identification; 4th, result reading. For half-automatic method, the 1st step and 3rd step are manually indentified. By experiments and practical application in industry, it proves that our calibration system is effective for more than hundreds of different types of dial instruments.

Validation of stratospheric water vapour measurements from the airborne microwave radiometer AMSOS

Abstract. We present the validation of a water vapour dataset obtained by the Airborne Microwave Stratospheric Observing System AMSOS, a passive microwave radiometer operating at 183 GHz. Vertical profiles are retrieved from spectra by an optimal estimation method. The useful vertical range lies in the upper troposphere up to the mesosphere with an altitude resolution of 8 to 16 km and a horizontal resolution of about 57 km. Flight campaigns were performed once a year from 1998 to 2006 measuring the latitudinal distribution of water vapour from the tropics to the polar regions. The obtained profiles show clearly the main features of stratospheric water vapour in all latitudinal regions. Data are validated against a set of instruments comprising satellite, ground-based, airborne remote sensing and in-situ instruments. It appears that AMSOS profiles have a dry bias of 0 to –20%, when compared to satellite experiments. Also a comparison between AMSOS and in-situ hygrosondes FISH and FLASH have been performed. A matching in the short overlap region in the upper troposphere of the lidar measurements from the DIAL instrument and the AMSOS dataset allowed water vapour profiling from the middle troposphere up to the mesosphere.

Widespread persistent near‐surface ozone depletion at northern high latitudes in spring

Springtime near‐surface ozone depletion has been observed at northern high latitudes. Due to limited observations, the spatial and temporal extent of low O3 concentrations near the surface is still unknown. A regional 3‐D chemistry and transport model is applied to simulate surface O3 depletion catalyzed by bromine radicals at northern high latitudes in March and April 2000. Satellite observations of BrO column by the ESA Global Ozone Monitoring Experiment (GOME) were processed to specify the BrO concentrations in the lower troposphere. In view of the GOME measurement and model uncertainties, the model results show an adequate agreement with the O3 depletion events observed at two surface sites, Alert, Canada (82.5°N, 62.3°W) and Barrow, Alaska (71.3°N, 156.6°W), and by airborne in situ and DIAL instrument during the TOPSE experiments at northern high latitudes. Low O3 events at Alert appear to be mostly driven by transport of O3‐poor air from high BrO regions. Model results indicate that low O3 concentrations (<20 ppbv) near the surface cover ∼60% of the northern high latitudes and that the depleted O3 concentrations (<10 ppbv) cover ∼20% of the region in April. The high BrO events tend to be large‐scale and persistent (1–2 weeks). We find that they are correlated with low temperature, a condition conducive for heterogeneous reactions on frozen snow or aerosol surfaces.

Scanning our past from madrid - The introduction of automatic telephone service in madrid

On 29 December 1926, His Majesty King Alfonso XIII, accompanied by His Royal Highness the Infante Fernando and the President of the Spanish government, General Primo de Rivera, presided at the inaugural formalities of the automatic telephone service in the city of Madrid. The formal ceremony was held at the exchange located in the district of Salamanca. This event was the culmination of a project designed by the International Telephone and Telegraph Corporation (IT&T) and carried out by the Compania Telefonica Nacional de Espana (CTNE) in just 16 months. A totally independent and entirely new telephone plant was installed together with the existing one, so the substitution of automatic for manual service was done in one effort, in contrast to the general and common practice in other large cities. The installation of equipment in the local exchanges, the laying of the underground cable network, the placement of telephones at subscribers' houses, and also the construction of new buildings were done simultaneously in a well-planned and coordinated way. And amazingly, no detail was forgotten. Even an advertising campaign to instruct the subscribers in the proper use of the dial instrument was organized and successfully implemented.

Tropospheric ozone measurements over the Great Athens Area during the medcaphot-trace campaign with a new shot-per-shot dial instrument: experimental system and results

Within the MEDCAPHOT-TRACE program of the European Community for studying the photochemical air pollution over the Great Athens Area, we report on 3-D lidar measurements of tropospheric ozone. After a general presentation of the DIAL technique, the experimental layout of our system which is equipped with a unique capability for real-time analysis of each individual optical backscattered signal is briefly described and its performance is assessed. The temporal evolution of the ozone concentration up to the top of the boundary layer is then followed over a few days. In particular, the first day of the photochemical smog episode is presented and commented.

A combined determination of wind velocities and ozone concentrations for a first measurement of ozone fluxes with a dial instrument during the MEDCAPHOT-TRACE campaign

From a data set collected during the MEDCAPHOT-TRACE field campaign, we demonstrate that ozone fluxes can be determined with a shot-per-shot DIAL instrument operated in the UV spectral region. This is done by the simultaneous reconstruction of ozone concentrations and of wind speeds using the same sample of lidar returns. A correlation scheme is used for the wind velocity retrieval, in which the transport of the spatial inhomogeneities of the aerosol backscattering coefficient along the optical path of the system is analyzed.

Measurements of the urban ozone vertical profile with an airborne CO_2 DIAL

An airborne DIAL system with two color pulsed CO(2) lasers has been developed for remote measurements of ozone distributions in an urban area. The airborne CO(2) DIAL is a nadir-directed and direct range-resolved system, since the system was designed to use aerosols between an aircraft and the ground surface as a distributed target. Flight tests were successfully conducted in September 1986 over Tokyo, Japan, at a flight altitude of 5000 ft (1.7 km). The airborne CO(2) DIAL instrument and its first measurements of the vertical profile of urban ozone are described.

An instrument for automatically recording waviness of surfaces

A prototype has been produced of an instrument that automatically records on graph paper the waviness of surfaces. The instrument possesses special features of design in the marking system that provide for accurate and rapid making of traces. It is of robust construction suitable for everyday production tests on surfaces and yet is of such form that it will not harm the surfaces. Its outstanding feature is that it charts the waviness of surfaces in only 5% of the time it takes when using a simple Ames dial instrument. The consequent saving in labour costs should be large in comparison with the cost of a production instrument.

A Remote Reading Dial Micrometer

A method is described by which the reading of a dial micrometer, or other dial instrument, may be transmitted electrically to a remote indicating or recording station. This is effected by attaching to the instrument a small detecting unit of simple construction. The modification does not interfere with direct reading of the instrument.