RMS phase dependence of the number of random point sources on laser illuminated surfaces

1979 ◽  
Vol 29 (2) ◽  
pp. 135-137
Author(s):  
J.Lynn Smith
Keyword(s):  
Point Sources ◽  
Random Point ◽  
Phase Dependence

Search time optimization for random pulse sources with given accuracy

2020 ◽  
Author(s):  
А.Л. Резник ◽  
А.В. Тузиков ◽  
А.А. Соловьев ◽  
А.В. Торгов ◽  
В.А. Ковалев
Keyword(s):  
A Priori ◽  
Search Algorithms ◽  
Point Sources ◽  
Random Point ◽  
Technical Diagnostics ◽  
Optimal Search ◽  
Localization Accuracy ◽  
Random Pulse ◽  
Time Optimal ◽  
Equivalent Problems

Исследуются вопросы построения быстродействующих алгоритмов обнаружения и локализации точечных источников, имеющих случайное распределение и обнаруживающих себя в случайные моменты времени генерацией мгновенных дельта-импульсов. Поиск осуществляется системой, включающей одно либо несколько приемных устройств, и выполняется с соблюдением требований по точности локализации. Предполагается, что все приемные устройства имеют произвольно перестраиваемые во времени окна обзора. Оптимальной считается процедура, которая в статистическом плане (т.е. по ансамблю реализаций) минимизирует среднее время локализации. Показано, что даже при сравнительно невысоких требованиях к точности локализации оптимальная процедура состоит из нескольких этапов, каждый из которых заканчивается в момент регистрации очередного импульса. Вполне допускается ситуация, когда в процессе оптимального поиска часть генерируемых источником импульсов может быть пропущена приемной системой. В работе рассчитаны и систематизированы параметры оптимального поиска в зависимости от количества приемных устройств и требуемой точности локализации. Для случая предельно высоких требований к точности локализации рассчитаны параметры асимптотически оптимальных поисковых алгоритмов. Показана возможность использования полученных результатов в многомерном случае. Purpose. The main goal of the research is to develop time-optimal algorithms for the localization of point sources that have a random spatial distribution and indicate themselves by generating instantaneous delta pulses at random time points. Methods. In many practically important problems requiring the highest reduction in the average time of localization of signal objects, the complexity of constructing optimal search algorithms forces researchers to resort to various kinds of simplifications or to the use of methods of numerical and simulation modelling. The mathematical apparatus used in the article belongs to probabilistic-statistical and non-linear programming methods. In a number of sections of the study (in particular, when constructing optimal control algorithms for multi-receiving search engines), traditional methods of discrete analysis and applied programming were used. Results. The solution of the variational problem is found, which minimizes the average localization time in the class of one-stage search algorithms with a known distribution density and the simultaneous absence of a priori information about the intensity of a random pulse source. For random point sources with a priori known intensity of the instantaneous generation of pulses, physically realizable multistage search algorithms have been constructed that have a significant gain in speed over single-stage algorithms, especially with increased requirements for localization accuracy. For a uniform distribution of a random source, an optimal strategy of multi-stage search was calculated, depending on the required localization accuracy and the number of receivers used. Findings. A distinctive feature of the studies is their universality, since in mathematical terms, the discussed problems and algorithms for the time-optimal search of random point-pulse objects arise in many scientific and technical applications. In particular, such studies are needed when developing methods for intermittent failures troubleshooting in the theory of reliability, in mathematical communication theory and in problems of technical diagnostics. Scientifically equivalent problems appear in the problems of detection, localization and tracking of radiation targets for eliminating malfunctions that manifest themselves in the form of intermittent failures. Scientifically equivalent problems arise in the problems of detecting, localizing and tracking radiation source targets.

Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

1976 ◽  
Vol 34 ◽  
pp. 572-573
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley
Keyword(s):  
Electronic Device ◽  
Point Sources ◽  
High Contrast ◽  
Variable Resistor ◽  
Quality Of Results ◽  
Low Contrast ◽  
Evaporation Source ◽  
And Control ◽  
At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

EVALUATION OF MOUNTAIN AREA AS NON-POINT SOURCE OF NITROGEN FOR SETO INLAND SEA: THE NORTHERN SHIKOKU REGION, JAPAN

2017 ◽  
Author(s):  
Shohei Morisawa ◽  
Shohei Morisawa ◽  
Yukio Komai ◽  
Yukio Komai ◽  
Takao Kunimatsu ◽  
...  
Keyword(s):  
Average Concentration ◽  
Point Sources ◽  
Seto Inland Sea ◽  
Mountain Streams ◽  
Unit Load ◽  
Mountain Areas ◽  
Mountain Area ◽  
The Seto Inland Sea ◽  
Unit Load Method ◽  
Important Position

The northern Shikoku region is located in the Western part of Japan and faces towards the Seto Inland Sea. The forest area, which is one of the non-point sources in the Seto Inland Sea watershed, occupies 75% of the land use in the watershed of the northern Shikoku region. The amount of loadings of nutrients and COD in the Seto Inland Sea has been estimated by the unit load method but actually the data has not been investigated. It is however, necessary to know the real concentration of nitrogen in mountain streams to evaluate the role which is the mountain area plays as non-point sources. Therefore, more water samples of mountain streams in the watershed need to be taken and the concentrations of nitrogen analyzed. The mountain streams in the northern Shikoku area were investigated from April, 2015 to November, 2015. The number of sampling sites was 283, in addition to the past data by Kunimatsu et al. The average concentration of nitrate nitrogen in Ehime, Kagawa, and Tokushima was 0.61mg/L, 0.78mg/L and 0.34mg/L, respectively. The environmental standard range for nitrogen in the Seto Inland Sea is from between less than 0.2mg/L and less than 1mg/L. Therefore, the average concentration of nitrogen in these regions was over category II, and those of mountain streams in Kagawa Prefecture exceeded category III. About 20% of mountain streams were more than 1mg/L. It has become clear that mountain areas occupy an important position as non-point sources for the Seto Inland Sea.

Nitrogen and phosphorus in the Vistula River, Poland -- changes from source to mouth

1994 ◽  
Vol 30 (5) ◽  
pp. 177-186 ◽  
Author(s):  
Karin Sundblad ◽  
Andrzej Tonderski ◽  
Jacek Rulewski
Keyword(s):  
Central Region ◽  
Northern Region ◽  
Point Sources ◽  
Nutrient Loss ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Concentration Data ◽  
Diffuse Sources ◽  
Vistula River ◽  
South Central

Nitrogen and phosphorus concentration data representing samples collected once a month for nine months at 13 locations along the Vistula River are considered in a preliminary discussion of the sources of the nutrients transported to the Baltic Sea. Concentrations in relation to flow data indicated substantial differences between subbasins. Based on those differences, on the area-specific nutrient loss for a six-month period and on the wastewater discharge in each subbasin, four regions could be recognized in the river basin: i) the southern region with a large impact of point sources, ii) the south central region, where diffuse sources seemed to be of major importance, iii) the north central region with a combined effect of point and diffuse sources, and retention in two reservoirs, iv) the northern region where point sources seemed to be the dominating source, at least for phosphorus. Our results illustrate the importance of differences in phosphorus retention between the basins. Long-term retention along the course of the river, particularly in the two reservoirs, must be estimated to allow proper source apportionment in the Vistula basin. Concentration decreases in the Wloclawek Reservoir varied between 44 and 68% for P, and 11 to 37% for N, in the months with significant retention. In some months, however, concentrations increased, indicating a release of nutrients.

UV-disinfection of treated wastewater: possible effects on surface waters

1994 ◽  
Vol 29 (12) ◽  
pp. 255-266 ◽  
Author(s):  
T. Gschlößl
Keyword(s):  
Uv Irradiation ◽  
Wastewater Treatment Plants ◽  
Technological Development ◽  
Research Work ◽  
Treatment Plant ◽  
Pilot Project ◽  
Point Sources ◽  
Treated Wastewater ◽  
Bathing Water Directive ◽  
Flowing Waters

UV-irradiation as an effective method of diminishing germs in the outlet of wastewater treatment plants was studied in a half-scale pilot-project sponsored by the State of Bavaria/BRD for a period of 3 years. Technical, physical and biological parameters capable of influencing this process were examined. The possibility to improve the hygienic and also the ecological structure of receiving waters was put to discussion. Possible effects of formed bypproducts upon the water biocoenosis of rivers were pointed out. The results demonstrated that UV-irradiation can diminish the number of germs in the outlet of a treatment plant to an extent which is sufficient to guarantee the maintenance of the bacteriological and presumably also the virological values set by the EC Bathing Water Directive. Nevertheless the UV-treatment process requires further technological development and research work concerning i.e. the improvement of hydraulic conditions, coat-forming on the quartz sleeves of the lamps, photochemical forming of by-products, after-growth and effects upon the localised benthic flora and fauna of the receiving water. It has to be stressed that a significant improvement of the bacteriological structure of flowing waters is only attainable, if the influx from non-point sources can be reduced simultaneously.

Evaluation and Avoidance of False Alarm by Controlling Rhine Water with Continuously Working Biotests

1994 ◽  
Vol 29 (3) ◽  
pp. 207-209 ◽  
Author(s):  
H. Puzicha
Keyword(s):  
Warning System ◽  
Point Sources ◽  
Trophic Levels ◽  
River Rhine ◽  
Wide Range ◽  
River Test ◽  
Continuous Working ◽  
Range Of Variation ◽  
Contaminant Load ◽  
Rhine Water

Effluents from point sources (industries, communities) and diffuse inputs introduce pollutants into the water of the river Rhine and cause a basic contaminant load. The aim is to establish a biological warning system to detect increased toxicity in addition to the already existing chemical-physical monitoring system. To cover a wide range of biocides, continuous working biotests at different trophic levels (bacteria, algae, mussels, water fleas, fishes) have been developed and proved. These are checked out for sensitivity against toxicants, reaction time, validity of data and practical handling under field conditions at the river. Test-specific appropriate methods are found to differentiate between the normal range of variation and true alarm signals.

Water Quality Prognosis and Cost Analysis of Pollution Abatement Measures in the Rhine Basin (The River Rhine Project: Ever)

1994 ◽  
Vol 29 (3) ◽  
pp. 95-106
Author(s):  
Alfred P. Benoist ◽  
Gerard H. Broseliske
Keyword(s):  
Water Quality ◽  
Pollution Abatement ◽  
Point Sources ◽  
Management Tool ◽  
River Rhine ◽  
Priority Pollutants ◽  
Rhine Basin ◽  
Frame Work ◽  
Water Quality Objectives ◽  
Calculation Models

For priority pollutants, the international Rhine Action Programme (RAP) aims to meet the quality objectives for the Rhine, set by the International Rhine Commission (IRC), by the year 2000. An assessment must be carried out to define additional measures exceeding best available technology (BAT) for point sources and best environmental practice (BEP) for diffuse sources for those priority pollutants still violating the quality objectives of the Rhine after implementing BAT and BEP only. To carry out the required assessments, an excessive amount of work and money is needed, including the application of sophisticated calculation models. For prioritizing reasons, the Institute for Inland Water Management and Waste Water Treatment (RIZA) initiated a project called EVER, which was conducted by DHV Water BV. EVER is the abbreviation of the Dutch equivalent for Effective Distribution of Emission Reductions (Effective Verdeling van Emissie Reducties). The aim of this project is to carry out a first and crude evaluation of the impact of abatement measures (BAT and BEP), as set by the IRC for the period 1985-1995. For those pollutants still showing a violation of the quality objectives for the Rhine in the year 1995, a range finding method is used, to predict the costs and impact of abatement measures exceeding BAT and BEP on the water quality of the Rhine. So, EVER is a management tool to prioritize the work to be done within the frame-work of the IRC, triggering the application of e.g. sophisticated calculation models for a selected number of priority pollutants. In EVER, the prognosis of the reduction of specific discharge rates for approximately forty priority pollutants is given for twelve sub-catchment areas for the year 1995. This prognosis is used to predict concentrations at eight international monitoring locations in the Rhine basin, using the discharges and concentrations of the year 1985 as a reference. The predicted concentrations for the year 1995 are compared with the (preliminary) water quality objectives as set by the IRC. The results indicate, that for six of the selected pollutants the number of available data is too small for sound predictions. Fifteen of the selected pollutants will satisfy the water quality objectives in 1995. Twenty (half) of the selected pollutants will still violate the quality objectives at several monitoring locations. These twenty pollutants are the basis for priorities to be set within the frame-work of the IRC for phase 3 (1995-2000) of the RAP. For these pollutants, additional abatement measures exceeding BAT and BEP are selected in EVER for the manageable groups of sources (anthropogenic non-point sources, industrial sources and municipal sources). Each measure is analyzed separately for costs and effectiveness. Finally the results of this project are integrated into a matrix system which will enable us to select the most effective mix of pollution abatement measures at the lowest costs. The result of the selected additional measures exceeding BAT and BEP shows that 17 pollutants will still violate the quality objectives.

Sources of Nitrogen and Phosphorus in the Catchment Area of Neusiedlersee/Fertö, Austria/Hungary

1993 ◽  
Vol 28 (3-5) ◽  
pp. 101-110 ◽  
Author(s):  
W. v. d. Emde ◽  
H. Fleckseder ◽  
N. Matsché ◽  
F. Plahl-Wabnegg ◽  
G. Spatzierer ◽  
...  
Keyword(s):  
Point Source ◽  
Catchment Area ◽  
Management Practice ◽  
Water Erosion ◽  
Nonpoint Source ◽  
Point Sources ◽  
Source Control ◽  
Nitrogen And Phosphorus ◽  
Catchment Areas ◽  
The One

Neusiedlersee (in German) / Fertö tó (in Hungarian) is a shallow lake at the Austro-Hungarian border. In the late 1970s, the question arose what to do in order to protect the lake against eutrophication. A preliminary report established the need for point-source control as well as gave first estimates for non-point source inputs. The proposed point-source control was quickly implemented, non-point sources were - among other topics - studied in detail in the period 1982 - 1986. The preliminary work had shown, based on integrated sampling and data from literature, that the aeolic input outweighed the one via water erosion (work was for totP only). In contrast to this, the 1982 - 1986 study showed that (a) water erosion by far dominates over aeolic inputs and (b) the size of nonpoint-source inputs was assessed for the largest catchment area in pronounced detail, whereas additional estimates were undertaken for smaller additional catchment areas. The methods as well as the results are presented in the following. The paper concludes with some remarks on the present management practice of nonpoint-source inputs.

Sources and transport of phosphorus in the Vltava river basin (Czech Republic)

1996 ◽  
Vol 33 (4-5) ◽  
pp. 137-144 ◽  
Author(s):  
Josef Hejzlar ◽  
Vojtech Vyhnálek ◽  
Jirí Kopácek ◽  
Jirí Duras
Keyword(s):  
Czech Republic ◽  
Population Density ◽  
Atmospheric Deposition ◽  
River Basin ◽  
Point Sources ◽  
Diffuse Sources ◽  
River Elbe ◽  
Municipal Wastewaters ◽  
Total P

Export and sources of P in the Vltava basin (subbasin of upper Elbe: total area – 28,093 km2; population density – 115 km−2; forests – 35%, farmland – 51%) were evaluated during 1972–1993. Annual export rates of total P from the basin to the river Elbe ranged between 38 and 68 kg km−2 a−1. Reservoirs with hydraulic retention times longer than 15 days were efficient traps for phosphorus retaining 20 to 30% of total P loading into the watercourses. Point sources (municipal wastewaters) were most important throughout the period and their share varied from approximately 60% in wet years to more than 90% in dry years. Export from diffuse sources (dominated by output from farmland) was highly dependent on discharge and fluctuaded between 5 and 40 kg km−2 a−1 in dry and wet years, respectively. Only about 2% of the P input into the basin from the fertilisation of farmland and from the atmospheric deposition was exported to the watercourses.

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