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This study was conducted in Lattakia Governorate (Burj Islam Village) to study the level of contamination of the greenhouses soil with the two organic phosphorous pesticides Dimethoate and Dichlorovos. The optimal wavelength was determined for the an alysis of both pesticides using High Performance Liquid Chromatography (HPLC) technology with UV/DAD detector. According to the results, the optimal wavelength for the analysis of Dimethoate is 200 nm, while it was 195 nm for the analysis of Dichlorovos. The recovery of Dimethoate was estimated at wavelength 200 nm which was 101.33 ± 3.868 and for dichlorvos at wavelength 195 nm when it was 98.995 ± 2.078. The results also showed that the greenhouses soil were contaminated with the residues of both pesticides, Dimethoate was detected in concentrations between (0.839 - 2.668) ppm, while Dichlorovos concentrations were between (10.046 - 44.359) ppm, indicating extensive use of both especially Dichlorovos, whose concentrations were higher than Dimethoate's in the studied sites.
In this research, we studied the supply linearity as function the usage time of NaI(Tl) scintillation detector through the experimental determination of the supply linearity of two identical NaI(Tl) detectors from the same manufacturer, one of which is much more used than the other
In this research, we studied a number of characteristics of two surface barrier detectors, one from LD and the other from PH, dedicated to detecting alpha particles. and comparing between characteristics of detectors. For the operating characteris tic, we found that the optimal operating voltage of the LD detector is located in the range (1.35-1.4) volts, while of the PH detector was located in the range (0.9-1.35) volts. For the detection capability, we found that the LD detector is better than the PH detector, this is due to the presence thinner metal surface layer for LD detector.,
In this paper an evaluation of image keypoints detectors and descriptors is presented when used for building panoramic image. The descriptors: (SIFT, SURF, BRIEF, ORB, BRISK, and FREAK) were discussed, when used with the appropriate keypoints detec tors on database taken indoors by RGB-D camera. Crosscheck and RANSAC (RANdom Sample Consensus) algorithms were used to find transform matrix between images. The speed of keypoints detectors and descriptors, the matching speed, the average of extracted keypoints, recall and precision were investigated. Oxford dataset was used to find the best descriptor for dealing with rotation and illumination changes that might occur due to changes in illumination angle. The obtained results showed that SIFT was the keypoint descriptor with the highest performance in non-real time applications. The SURF/BRISK was the best detector/descriptor which can be used in real time applications with comparable SIFT's results.
In this paper, we propose an implementation of hierarchical failure detectors, which depends on dividing the processes into sub-groups and elect one leader called the main process . The main process then distributes the remaining processes into g roups and chooses one leader for each one. Finally failure detector applied in the chosen leaders which send the results to the central process.
The effect of thermal noise and shot noise on the receiver sensitivity in a digital optical communication system will be studied and analyzed. Also, the positive and negative effects of Parameters on the receiver sensitivity will be highlighted. Th e programming tools (MATLAB) is used to study the relationship between the receiver sensitivity and bit rate. It showed that the shot-noise-limited receiver sensitivity is much better than the thermal -noise-limited receiver sensitivity with best 30dB. The study also provided an explanation for the preference of optical detector (APD) compared to that in (PIN) optical detector from sensitivity side due to its internal gain, this can be achieved when the thermal noise is dominant. However, the preference of optical detector(PIN) will be better in case of shot noise is dominant. Analyzed results show that there is a significant improvement in the shot-noiselimited receiver sensitivity for high quantum efficiency and high wavelength. However, the sensitivity is deteriorated to get a lower error rate. The thermal -noise-limited receiver sensitivity showed an improving by increasing the responsivity and the load resistance. However, it decreases by increasing the number of noise and the error rate.
In this work, using a scintillation detector with Strontium-90 source as a try to measure the electronic neutrino mass from a simple technique and different from what is used in this area where current techniques used are very complex and require s ubstantial amounts. Also, detector calibration (to find the straight calibration equation), in addition to identified the maximum energy of β- particles (electrons), experimentally, by selection the channel number and then finding the energy value from the calibration equation (as a straight line). We have studied the disintegration changed energy with absorbent material which is an aluminum slices that have different thickness. We have observed the decrease in the values of the maximum energy of the electrons with increases the thickness of the slices. The energy changes with thickness as: E = f (x), (a straight line have a negative inclination). Applying Fermi 's theory and Kurie's plot allowed to find the maximum energy of disintegration electrons (1697,58 keV), this value is so close to experimental value (1653,45 keV), with dubity (2,6%) We have found that the electronic mass neutrino mass is almost to be non-existent, or we can said that the Strontium-90 disintegration does not allow to measure mass neutrino mass accurately, this is due to the high value of the disintegration energy of the Strontium- 90 isotope.
Tylosin and Spiramycin are medium-spectrum macrolide antibiotic used exclusively in veterinary medicine for the treatment of a wide range of infections.This research deals with the determination of optimal conditions for simultaneous separation and d etermination of two macrolides antibiotics (Tylosin and Spyramicine), using C8 and C18 Chromatographic separation columns and doing the comparison between them in order to develop a rapid and sensitive method which can be used to measure these two compounds using High Performance Liquid Chromatography – Diode array detector (HPLC-DAD). This study has used the gradient elution for mobile phase and revealed that the best conditions for separation and determination are conjugated with the best retention times and best areas for both studied compounds using a mobile phase consisted of an aqueous solution of anhydrated disodium Hydrogen Phosphate at pH=2.4 and an organic solution of acetonitrile with a ratio of 80:20v/v (solution A) and acetonitrile (solution B) [Na2HPO4(0.04M) pH:2.4/CAN (80:20v/v)]/ ACN, temperature 40°C for both columns, flow ratio of 1ml/min. for the mobile phase and maximum absorption wave length 280 nm, 232nm for Tylosin and Spyramicine respectively. The best peak areas are recorded as 5.759, 5.927 for Tylosin and Spyramicine 0.10ppm respectively, using C8 Chromatographic separation column in comparison with the best peak areas 4.432, 4.212 respectively at the same concentration using C18 Chromatographic separation column. It was noticed that the best retention times for Tylosin and Spyramicine were 7.013, 4.214min. respectively at concentration of 0.10ppm using C8 Chromatographic separation column in comparison with the best retention times 7.641, 5.898min. respectively at the same concentration using C18 Chromatographic separation column. The calibration curves for both separated compounds on C8 Chromatographic separation column showed a good linearity within a concentration range of 0.0010-0.10 ppm ≈ 1-100ppb at the two wave lengths λmax. = 280, 232nm respectively.
In this experimental work, the instruments used (detector, calibrating sources) has been calibrating, the calibration line of the detector deduced and it has been finding that the equation of calibration line takes the form: The resolution power R has been studying as function of the distance between the activity source and detector; the results obtained show that R decrease by increase the energy of the lines spectrum, this mean that the detector resolution power become bigger. It has been measured the LC، LD and MDA using two different methods of background radiation value, trapezium method and classical method, for two different distances between radioactivity source and detector: (9,3cm) and (10cm). The results show: 1- There is similar comportment of the LC، LD and MDA in function energy and the distance between radioactivity source and detector. 2- The trapezium method gives better results from the classical method to the radiation background, and this leads to lesser MDA value, this means that the sensibility is bigger to measure this quantity. 3- The relative error using MDA is (5%) for large values, and (10%) for small values
Traffic jam is a serious problem in our life, it causes waste of time and energy, conventional traffic light control system works with a fixed time and fixed cycle. This paper proposes an intelligent traffic light control system with a changeable gre en time and cycle depending on traffic density. Traffic parameters (cars’ numbers, density, flow) are collected by Loop Detectors located at each traffic signal, this data will be transmitted to the PLC controller then, PLC processes this data to produce controlling commands, it is also connected to a SCADA system which supervises the process and provides an automatic and manual control. The proposal system applies Green Wave method to connect between two junctions based on a real car velocity and sets priority for emergency car, when Loop Detector detects this car the program will be interrupted to open the traffic light needed. This intelligent system is experimented with conventional control system s’ data the obtained result is promising, it can reduce the green time, cycle time, and delayed time of each car at traffic light to its’ minimum value.
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