Dynamic light intensity detection system of aerodrome assistance light

2008 ◽  
Author(s):  
Jianshu Gao ◽  
Jiye Song ◽  
Zhijing Yu ◽  
Fei Chen ◽  
Xudong Shi ◽  
...  
2020 ◽  
Vol 19 (01) ◽  
pp. 11-22
Author(s):  
Almira Budiyanto ◽  
Abdul Manan ◽  
Elvira Sukma Wahyuni

The more advanced the technology and the greater the community's need to carry out activities every day, the number of vehicles on the highway is getting crowded. From year to year, the greater the level of traffic accidents caused by many factors, among the usual reasons is the loss of awareness of the driver when driving a vehicle especially drowsiness. One of the drowsiness parameters is the frequency eye blinks. Therefore, to get the drowsiness symptoms, the purpose of this research is to detect the eye blinks, which in turn reduce the level of accidents by detecting sleepy eyes based on digital image processing. The method used to detect both eyes is the Viola-Jones method. The detection of both eyes can also acquire the duration of closed eyes and the number of eye blinks. A person can be said to be sleepy by means of sleepiness parameters determined by a study. The research shows that detection of eye blinks using the Viola-Jones method has a fairly high accuracy of up to 84.72% if the face condition is upright and tilted no more than 45 degrees. Another conclusion is that eye detection and driver detection are more effective at certain light intensity values which are around 2-33 lux.


1981 ◽  
Vol 89 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Y Hiramoto ◽  
Y Hamaguchi ◽  
Y Shôji ◽  
S Shimoda

A method of polarization optical analysis is described in which phase retardation attributable to birefringence of a minute area in a microscopic object is determined. The optical system consists of a polarizing microscope with "rectified" strain-free lenses, a photoelectric detector to determine the intensity of the light passing through a minute window located at the image plane of the specimen, and a stage that moves the specimen at appropriate velocities for scanning. The error resulting from any flare of light emerging from outside of the area to be measured is minimized by limiting the illuminated area. The specimen can be observed during the measurement of light intensity by illuminating the whole microscope field at a wavelength different from that of the light used for the measurement. The retardation of the specimen is determined by comparing the specimen and background intensities as functions of the azimuth of a Brace-Köherl compensator. Alternatively, retardation is obtained directly from the light intensity at a fixed compensator angle, using the theory of polarization optics. The basal noise level for the present apparatus is approximately 0.03 nm when measuring birefringence of a 4-micron2 area in 0.1 s, using a X 40, NA 0.65 objective. The noise decreases in inverse proportion to the square root of the area times the duration of measurement.


Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5081
Author(s):  
Qu ◽  
Liu ◽  
Deng ◽  
Xu ◽  
Hu ◽  
...  

A PSD-based solar spot position detection system is developed for solar tracking closed-loop control of mobile SOF-FTIR (Solar Occultation Flux method based on Fourier Transform Infrared spectrometer). The positioning error factors of PSD (position sensitive detector) are analyzed in detail. A voltage model for PSD signal conditioning circuit has been established to investigate the noise factors. The model shows that the positioning error is mainly related to PSD dark current and circuit gain. A static voltage deduction calibration method based on genetic algorithm is proposed to eliminate the effect of dark current. The gain ratio between channels is calculated based on the fitting curve slope of discrete position data of PSD center point with different light intensity for circuit gain calibration. The positioning accuracy and precision are greatly enhanced, especially when the light intensity is weak, compared with uncalibrated results. The positioning accuracy of center, middle and edge areas of PSD can reach 0.14%, 0.49%, and 1.09%, respectively, after correction in the range of light intensity voltage from 40 mV to 20 V. The corresponding standard deviations of each region are 0.005, 0.009, and 0.014, respectively. The adjustment methods proposed in this paper improve both measurement accuracy and detection limit. The results demonstrate that the calibrated PSD positioning accuracy can meet the requirements of SOF-FTIR for solar tracking.


Author(s):  
Bakhtiar Alldino Ardi Sumbodo ◽  
Ariestyo Rahardian

The development of quadrotor type AR. Drone for research are being developed. One of which is an object detection system based image processing to perform the mission, such as tracking, landing, or detect and pass the object hitch. Accordingly, in this research designed an ARTag detection system based on digital image processing using OpenCV library implemented in ROS platform used to connect the drone to PC which will then be carried out missions to landing. The method used is Thresholding, Contour Detection, and Image Moments.The result of this research is a system that able to detect ARTag objects along with his ID. The system is tested by computing time of the program in the static and dynamic state, detection performance testing in static and dynamic state, detection performance testing of the angle between the ARDrone and ARTag, detection performance testing of the light intensity, and testing landing mission. The conclusions are the optimal height of detection in the static and dynamic state is 150 cm, has excellent reliability to the light intensity, and the ARDrone can perform landing mission with a success rate of 70%.


2021 ◽  
Author(s):  
Farid Baskoro ◽  
Bambang Suprianto ◽  
Asri Bekti Pratiwi ◽  
Lilik Anifah ◽  
Aristyawan Putra Nurdiansyah ◽  
...  

2013 ◽  
Vol 462-463 ◽  
pp. 104-107
Author(s):  
Yun Hua Zhou

With the needs of the society development, the light intensity detection technology has gradually into the lighting control, health care, biological research and other fields. Based on many fields and equipments for the light requirement, this paper proposed and designed a light intensity detection system. The hardware circuit used the STM32F103VB as the main controller; collocate with BH1750 digital light intensity sensor and LCD module, the power supply module. The design of software used the modular design, including data acquisition, data display, and intelligent control module. After the practical application, the detection system works well.


Author(s):  
J. B. Warren

Electron diffraction intensity profiles have been used extensively in studies of polycrystalline and amorphous thin films. In previous work, diffraction intensity profiles were quantitized either by mechanically scanning the photographic emulsion with a densitometer or by using deflection coils to scan the diffraction pattern over a stationary detector. Such methods tend to be slow, and the intensities must still be converted from analog to digital form for quantitative analysis. The Instrumentation Division at Brookhaven has designed and constructed a electron diffractometer, based on a silicon photodiode array, that overcomes these disadvantages. The instrument is compact (Fig. 1), can be used with any unmodified electron microscope, and acquires the data in a form immediately accessible by microcomputer.Major components include a RETICON 1024 element photodiode array for the de tector, an Analog Devices MAS-1202 analog digital converter and a Digital Equipment LSI 11/2 microcomputer. The photodiode array cannot detect high energy electrons without damage so an f/1.4 lens is used to focus the phosphor screen image of the diffraction pattern on to the photodiode array.


Author(s):  
P. Trebbia ◽  
P. Ballongue ◽  
C. Colliex

An effective use of electron energy loss spectroscopy for chemical characterization of selected areas in the electron microscope can only be achieved with the development of quantitative measurements capabilities.The experimental assembly, which is sketched in Fig.l, has therefore been carried out. It comprises four main elements.The analytical transmission electron microscope is a conventional microscope fitted with a Castaing and Henry dispersive unit (magnetic prism and electrostatic mirror). Recent modifications include the improvement of the vacuum in the specimen chamber (below 10-6 torr) and the adaptation of a new electrostatic mirror.The detection system, similar to the one described by Hermann et al (1), is located in a separate chamber below the fluorescent screen which visualizes the energy loss spectrum. Variable apertures select the electrons, which have lost an energy AE within an energy window smaller than 1 eV, in front of a surface barrier solid state detector RTC BPY 52 100 S.Q. The saw tooth signal delivered by a charge sensitive preamplifier (decay time of 5.10-5 S) is amplified, shaped into a gaussian profile through an active filter and counted by a single channel analyser.


Author(s):  
C.V.L. Powell

The overall fine structure of the eye in Placopecten is similar to that of other scallops. The optic tentacle consists of an outer columnar epithelium which is modified into a pigmented iris and a cornea (Fig. 1). This capsule encloses the cellular lens, retina, reflecting argentea and the pigmented tapetum. The retina is divided into two parts (Fig. 2). The distal retina functions in the detection of movement and the proximal retina monitors environmental light intensity. The purpose of the present study is to describe the ultrastructure of the retina as a preliminary observation on eye development. This is also the first known presentation of scanning electron microscope studies of the eye of the scallop.


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