scholarly journals A Study on the Blue Coloration of Ao-ike Pond, Aomori Prefecture, Japan: Formulation of a Physical Model in Terms of Radiance and Image Analyses

2021 ◽  
Vol 11 (19) ◽  
pp. 9231
Author(s):  
Ryuji Hanaishi ◽  
Kazuhisa A. Chikita
Keyword(s):  
Density Fluctuation ◽  
Suspended Solids ◽  
Red Light ◽  
Mie Scattering ◽  
Tree Leaves ◽  
Before And After ◽  
Irregular Reflection ◽  
Aomori Prefecture ◽  
Blue Coloration ◽  
Image Analyses

The blue coloration model of a closed pond, Ao-ike Pond, Aomori Prefecture, Japan, was formulated in terms of radiance by applying a theory of observation devices proposed by Szirmay-Kalos (2008) and Hanaishi’s reverse ray tracing method. In this model, three potential contributions to the coloration were considered; irregular reflection at the Lambertian pond bottom, density fluctuation scattering by water, and Mie scattering by suspended solids. By utilizing model formulas for these mechanisms, some parameters were determined in order to duplicate the images of the pond surface without solar shading by tree leaves above the pond surface, in addition to the images with sunbeam trajectories by solar radiations passing through tree leaves, which are emitted from the water and visible on the surface. Simulating the pictures of the pond surface and the sun-beam-image analyses revealed that the blue colorations of Ao-ike Pond are mainly produced (1) by the density fluctuation scattering of water itself and the white Mie scattering by suspended solids and (2) by the red-light absorption by water in the optical paths before and after the two scatterings. Then, the density fluctuation scattering of water and the Mie scattering by suspended solids exhibited contributions of almost equal magnitude. The contribution of irregular reflections at the pond bottom was judged to be relatively small.

scholarly journals Evaluation of Automated Enforcement Program in Amman

2018 ◽  
Author(s):  
Hana Naghawi ◽  
Bushra Al Qatawneh ◽  
Rabab Al Louzi
Keyword(s):  
Traffic Safety ◽  
Questionnaire Survey ◽  
Positive Impact ◽  
Red Light ◽  
Crash Frequency ◽  
Red Light Running ◽  
Red Light Cameras ◽  
Percent Confidence Level ◽  
Before And After ◽  
Traffic Violations

This study aims, in a first attempt, to evaluate the effectiveness of using the Automated Enforcement Program (AEP) to improve traffic safety in Amman, Jordan. The evaluation of the program on crashes and violations was examined based on a “before-and-after” study using the paired t-test at 95 percent confidence level. Twenty one locations including signalized intersections monitored by red light cameras and arterial roads monitored by excessive speed cameras were selected. Nine locations were used to study the effectiveness of the program on violations, and twelve locations were used to determine the effectiveness of the program on frequency and severity of crashes. Data on number and severity of crashes were taken from Jordan Traffic Institution. Among the general findings, it was found that the AEP was generally associated with positive impact on crashes. Crash frequency was significantly reduced by up to 63%. Crash severities were reduced by up to 62.5%. Also, traffic violations were significantly reduced by up to 66%.  Finally, drivers’ opinion and attitude on the program was also analyzed using a questionnaire survey. The questionnaire survey revealed that 35.5% of drivers are unaware of AEP in Amman, 63.9% of drivers don’t know the camera locations, most drivers knew about excessive speed and red light running penalties, most drivers reduce their speed at camera locations, 44.4% of drivers think that the program satisfies its objective in improving traffic safety and 52% of drivers encourage increasing the number of camera devices in Amman.

Spatial and seasonal distribution of phosphorus in the mainstem within the Three Gorges Reservoir before and after impoundment

2015 ◽  
Vol 73 (3) ◽  
pp. 636-642 ◽  
Author(s):  
Baofeng Lou ◽  
Shiyong Yin
Keyword(s):  
Water Level ◽  
Three Gorges Reservoir ◽  
Suspended Solids ◽  
Seasonal Distribution ◽  
Three Gorges ◽  
Target Level ◽  
Wet Season ◽  
The Three Gorges Reservoir ◽  
The Three Gorges ◽  
Before And After

The Three Gorges Reservoir (TGR) began to store water in 2003. The water level reached 135 m in 2003, 156 m in 2006, 172 m in 2008 and 175 m (target level) in every year from 2010 through 2013. Impacts of dams on the environment are a concern all over the world. A major concern for reservoirs is phosphorus and possible eutrophication. Therefore, total phosphorus (TP) in the TGR mainstem was determined at five stations (S1–S5) from 1998 through 2013 to investigate variations of phosphorus with water level elevations. Results revealed that a new spatial and seasonal TP distribution has occurred after the impoundment. TP levels in the reach between S3 (nearly 300 km from the dam) and S5 (near the dam) have decreased sharply compared with those before the impoundment. The reduction degree of TP in wet season was greater than in dry season. Additionally, TP spatially decreased from upstream to the dam after the impoundment. The reduction of TP levels was mainly attributed to the settling of suspended solids and adsorbed phosphorus. These findings will inform research about transport and fate of phosphorus in TGR and Yangtze River. The challenge remains to implement measures to limit the release of phosphorus from sediments.

Development of a flocculation sub-model for a 3-D CFD model based on rectangular settling tanks

2011 ◽  
Vol 63 (2) ◽  
pp. 213-219 ◽  
Author(s):  
M. Gong ◽  
S. Xanthos ◽  
K. Ramalingam ◽  
J. Fillos ◽  
K. Beckmann ◽  
...  
Keyword(s):  
New York ◽  
Suspended Solids ◽  
Cfd Model ◽  
Mixed Liquor ◽  
City College ◽  
Solids Loading ◽  
Before And After ◽  
Computational Fluid Dynamics Cfd ◽  
3D Computer Model ◽  
Relationship Of

To assess performance and evaluate alternatives to improve the efficiency of rectangular Gould II type final settling tanks (FSTs), New York City Department of Environmental Protection and City College of NY developed a 3D computer model depicting the actual structural configuration of the tanks and the current and proposed hydraulic and solids loading rates. Fluent 6.3.26™ was the base platform for the computational fluid dynamics (CFD) model, for which sub-models of the SS settling characteristics, turbulence, flocculation and rheology were incorporated. This was supplemented by field and bench scale experiments to quantify the coefficients integral to the sub-models. The 3D model developed can be used to consider different baffle arrangements, sludge withdrawal mechanisms and loading alternatives to the FSTs. Flocculation in the front half of the rectangular tank especially in the region before and after the inlet baffle is one of the vital parameters that influences the capture efficiency of SS. Flocculation could be further improved by capturing medium and small size particles by creating an additional zone with an in-tank baffle. This was one of the methods that was adopted in optimizing the performance of the tank where the CCNY 3D CFD model was used to locate the in-tank baffle position. This paper describes the development of the flocculation sub-model and the relationship of the flocculation coefficients in the known Parker equation to the initial mixed liquor suspended solids (MLSS) concentration X0. A new modified equation is proposed removing the dependency of the breakup coefficient to the initial value of X0 based on preliminary data using normal and low concentration mixed liquor suspended solids values in flocculation experiments performed.

scholarly journals Repellency Effect of Prepared Neem Tree Leaves Smoke against Mosquito

2020 ◽  
pp. 1-6
Author(s):  
M. M. Jibrin ◽  
A. D. Mohammed
Keyword(s):  
Adverse Effect ◽  
Rating Scale ◽  
Distilled Water ◽  
Tree Leaves ◽  
Neem Tree ◽  
Constant Weight ◽  
Prepared Sample ◽  
Time Of Application ◽  
Neem Leaves ◽  
Before And After

The study was design to evaluate the smoke repellency effect of prepared neem leaves, against mosquito. The dried neem powder was used for making the insecticide, 10 g of powdered leaves sample was weight into a 200 ml beaker, and 5.0 g of starch was weight and added to the leave sample in the beaker. The mixture was stirred and 5.0 ml of distilled water was added gradually to the mixture in little quantity while stirring. The beaker with wet insecticide mixture was dried in an oven until a constant weight was obtained. The prepared neem insecticide was distributed among the households to use at night, to substitute synthetic insecticides. The users were randomly selected within the study area. The data was collected based on the time of application, number of bites receive before and after the application this was done based on 0-5 rating scale. The result revealed that the prepared insecticide is 100% effective though the effectiveness is dependent to time taken after application. The questionnaire was also used to assess the view of the users on the adverse effect they experienced upon the exposure to neem tree leaves prepared sample. The study has been concluded that neem leaves smoke is effective in repelling mosquito, and it can be an alternative to the synthetic insecticides hence it is safe for the users and the environment.

scholarly journals Badania możliwości zastosowania materiałów obciążających do wspomagania oczyszczania wód złożowych

Nafta-Gaz ◽  
2021 ◽  
Vol 77 (4) ◽  
pp. 255-263
Author(s):  
Andrzej Janocha ◽  
◽  
Dorota Kluk ◽  
Keyword(s):  
Water Treatment ◽  
Suspended Solids ◽  
Treatment Process ◽  
Solid Particles ◽  
Reservoir Water ◽  
Simple Method ◽  
Water Treatment Process ◽  
Coagulation And Flocculation ◽  
Before And After ◽  
Porosity And Permeability

The article presents the issues related to of the removal of suspensions and sediments from reservoir waters. In the conducted research, particular emphasis was placed on the techniques of using loading materials in the water treatment process. The research materials were four types of reservoir water, which was collected from the separators of wells exploiting natural gas deposits. These waters were characterized by high suspended solids (76–176 mg/dm3) and a varied degree of mineralization. The content of dissolved substances was determined in the range from 401 to 306 428 mg/dm3. The extracted reservoir waters are currently most often utilized by pumping into the absorbing horizons in depleted hydrocarbon reservoirs. The preparation of water for injection is limited only to the removal of easily settling solid particles and suspensions present in the extracted formation waters. The porosity and permeability of the deposit rocks determine the size of solid particles present in the water that can be forced into voids in the porous medium. In the process of water treatment by coagulation and flocculation, carried out in laboratory conditions, Flokor ASW was used as a coagulant, while Stabpol was used as a flocculant. Post-coagulation sludge is highly hydrated, so that its density is close to that of water, as a result of which sedimentation of sludge particles takes a long time. In order to increase the sedimentation rate of particles contained in the treated waters, ballasting materials, which were quartz sand and bentonites: powdery bentonite and bentonite preparation DuoBent 1, were successively introduced into the solutions. The effectiveness of the water treatment process was assessed by comparing the degree of turbidity of the solution above the sediment before and after adding a different amount of coagulant, flocculant and sediment-balancing materials. The turbidity measurement of the tested solutions allows to estimate the content of suspensions and colloids in them. Laboratory tests were carried out on the possibility of using selected materials ballasting suspensions in the process of reservoir water treatment. Effective doses of ballast materials recommended for use in the separation of suspensions from formation waters were determined. Research results presented in this paper show that the removal of suspended solids from formation waters can be carried out with the use of a properly prepared bentonite agent (DuoBent 1) with no need of adding other chemical compounds. The doses of the DuoBent 1 bentonite preparation, dosed into highly mineralized reservoir waters in order to remove turbidity, are relatively small. Adding bentonite into the treated waters in amounts exceeding 0.2 g/dm3 results in obtaining high clarity of the water intended for injection (turbidity at the level of 0–5 FAU). The results of the research can be implemented for practical use as a simple method of purifying reservoir water prior to injection into the formation.

scholarly journals Enhancing color quality of WLEDs with dual-layer remote phosphor geometry

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Phung Ton That ◽  
Nguyen Thi Phuong Loan ◽  
Le Van Tho ◽  
Nguyen Doan Quoc Anh ◽  
Hsing-Yuan Liao ◽  
...  
Keyword(s):  
Red Light ◽  
Mie Scattering ◽  
Phosphor Layer ◽  
Color Quality ◽  
Remote Phosphor ◽  
Different Color ◽  
Light Components ◽  
Two Parameters ◽  
Color Rendering

Abstract Usually, remote phosphor structures are beneficial in terms of flux but unfavorable in terms of color quality compared to conformal phosphor or in-cup phosphor packages. To eliminate this disadvantage, many studies have focused on increasing the chromatic quality of the remote phosphor configuration, which requires great efforts in improving two parameters of color: color rendering index (CRI) and color quality scale (CQS). CRI is known as the most useful quantitative method used to measure the ability of a light source to reproduce the colors of illuminated objects faithfully and naturally. Similarly, CQS is also a method of lighting quality determination and analysis, especially used as an alternative to the unsaturated CRI colors. In this paper, we proposed dual-layer remote phosphor structure as a novel method of CRI and CQS enhancement to improve WLEDs’ color quality. Five alike WLEDs but having different color temperatures in the range of 5600 K to 8500 K were applied in this study. The idea behind the study is to place a red phosphor layer SrwFxByOz:Eu2+,Sm2+ on the yellow phosphor layer YAG:Ce3+ and then determining an appropriate concentration of SrwFxByOz:Eu2+,Sm2+ added to achieve the highest color quality. The results point out that SrwFxByOz:Eu2+,Sm2+ brings great benefits to the improvement of CRI and CQS parameters. Specifically, the higher the SrwFxByOz:Eu2+,Sm2+ concentration results in the greater CRI and CQS, owning to the enriched red light components in the WLEDs. However, the flux has a tendency of dropping when SrwFxByOz:Eu2+,Sm2+ concentration rises excessively. This has been proved by using the Mie-scattering theory and the Lambert-Beer law. The results of this article are essential references for manufacturing WLEDs with higher chromatic quality.

Treatment of road runoff by coagulation/flocculation and sedimentation

2019 ◽  
Vol 79 (3) ◽  
pp. 518-525 ◽  
Author(s):  
F. Nyström ◽  
K. Nordqvist ◽  
I. Herrmann ◽  
A. Hedström ◽  
M. Viklander
Keyword(s):  
Laboratory Investigation ◽  
Treatment Effect ◽  
Metal Content ◽  
Suspended Solids ◽  
Metal Reduction ◽  
Stormwater Treatment ◽  
Road Runoff ◽  
Coagulation Process ◽  
Before And After ◽  
Rain Events

Abstract A laboratory investigation of the treatment potential of a coagulation process in the context of stormwater treatment was undertaken. The initial 25 L road runoff generated from four rain events was collected and subjected to a jar-testing regime with two commercial coagulants. The treatment effect was assessed by analysing the runoff before and after treatment for turbidity, suspended solids and metal content. The coagulation process resulted in particle and total metal reduction of more than 90% compared to 40% for only sedimentation. Up to 40% reduction of dissolved Cr, Cu and Pb was also observed compared to 0% for sedimentation. This study shows that coagulation may be a useful process for stormwater treatment systems when the treatment requirements are high.

Evaluation of the performance of the Tyson Foods wastewater treatment plant for nitrogen removal

2005 ◽  
Vol 51 (11) ◽  
pp. 159-166
Author(s):  
E. Ubay-Cokgor ◽  
C.W. Randall ◽  
D. Orhon
Keyword(s):  
Wastewater Treatment ◽  
Nitrogen Removal ◽  
Wastewater Treatment Plant ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Biological Oxygen Demand ◽  
Average Flow Rate ◽  
Before And After

In this paper, the performance of the Tyson Foods wastewater treatment plant with an average flow rate of 6500 m3/d was evaluated before and after upgrading of the treatment system for nitrogen removal. This study was also covered with an additional recommendation of BIOWINTM BNR program simulation after the modification period to achieve an additional nutrient removal. The results clearly show that the upgrading was very successful for improved nitrogen removal, with a 57% decrease on the total nitrogen discharge. There also were slight reductions in the discharged loads of biological oxygen demand, total suspended solids, ammonium and total phosphorus with denitrification, even though the effluent flow was higher during operation of the nitrogen removal configuration.

An integrating sphere for the rapid nondestructive estimation of whole-plant chlorophyll content

1983 ◽  
Vol 61 (12) ◽  
pp. 3072-3079 ◽  
Author(s):  
F. D. H. Macdowall
Keyword(s):  
Chlorophyll Content ◽  
Scattered Light ◽  
Red Light ◽  
Quadratic Equation ◽  
Coefficient Of Determination ◽  
Integrating Sphere ◽  
Selective Absorption ◽  
Chlorophyll Contents ◽  
Whole Plant ◽  
Before And After

The chlorophyll contents of seedlings of several plant species were estimated from the voltages emitted by a photocell before and after the insertion of the shoot systems into a 61-cm integrating sphere. Red light of 675-nm wavelength was projected into the sphere for selective absorption by chlorophyll, as shown by an absorption spectrum, and the readout was calibrated against total extracted chlorophyll. The species and thus the morphology of the plant were of no significant consequence. The absorbance by chlorophyll in plants obeyed Beer's law up to a content of about 60 mg chlorophyll; however, over a wider range the calibration curve for absorbance, like that for absorptance, was best fitted by a quadratic equation which gave a coefficient of determination of 98% and a standard error of estimate for chlorophyll of 2 mg. A band width of 4 mg chlorophyll was obtained between the 95% confidence limits for chlorophyll as a function of absorbance of plants that contained less than 20 mg chlorophyll. A similar 4-mg confidence belt for chlorophyll on absorptance applied through the range of about 5 to 45 mg chlorophyll in plants. A usable linear relation was obtained between chlorophyll content and the ratio of the scattered light not absorbed at 750 nm to that at 675 nm.

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