The Use of Standard Alpha and Beta Surface Scintillation Contamination Monitors to Confirm the Contamination Fingerprint and to Check on Source Quality

2011 ◽  
Author(s):  
Pete Burgess
Keyword(s):  
Count Rate ◽  
Surface Condition ◽  
Surface Contamination ◽  
Ratio Method ◽  
Channel Ratio ◽  
Alpha Channel ◽  
Channel Analysis ◽  
Alpha Beta ◽  
Set Up ◽  
Counting Window

Normally, beta and alpha surface contamination monitors are used with a simple counting threshold, i.e. any pulse over a predetermined amplitude is counted. This is very different from gamma monitoring, where the use of counting windows is very popular and the use of full multi-channel analysis is common. Many current surface contamination ratemeters have the capacity to drive dual phosphor detectors and can be set up to provide beta and alpha channels. Effectively, the beta channel is a counting window, i.e. all pulses which are bigger than the threshold and smaller than the alpha threshold are counted. Larger pulses go into the alpha channel. This paper addresses how this can be used with beta only and alpha only detectors to provide information on the source. The detector is set up conventionally to a defined point for the lowest beta energy anticipated. The instrument is then switched to alpha + beta mode and the alpha threshold set to 3 times the beta threshold. With this set up, the alpha to beta channel count rate ratio varies smoothly by a factor of 14 between Y-90 (Emax 2.27 MeV) and C-14 (Emax 0.16 MeV). Hence the instrument can be used to estimate the energy of an unknown beta contaminant or to confirm that a mixed beta fingerprint has essentially the same mix. The same approach can be used with alpha probes to confirm the source quality. The main worry with alpha monitoring is the surface condition. A poor surface condition will lead to a low count rate. Using the channel ratio method will identify grubby sources. The resulting ratio can be used either as a go/no trigger, i.e. any surface with a low ratio will be treated as untrustworthy, or alternatively the ratio can be used to correct the reading to give a better estimate of surface activity.

Ticket Income Distribution of Urban Rail Transit in Network Operating Condition

2011 ◽  
Vol 243-249 ◽  
pp. 4375-4380
Author(s):  
Yuan Chun Huang ◽  
Jian Li ◽  
Haize Pan
Keyword(s):  
Income Distribution ◽  
Urban Rail Transit ◽  
Ratio Method ◽  
Rail Transit ◽  
Matching Algorithm ◽  
Factors Affecting ◽  
Urban Rail ◽  
Set Up ◽  
Urban Rail Transit Network ◽  
Factor Matching

Through analyzing the factors affecting passengers’ path-choice, the corresponding principles and rules of the ticket income distribution are put forward and the new model of the Urban Rail Transit Network in Beijing is set up in the paper. Through the deformation of the urban rail transit and the simplification of the lines, the topology of the urban rail transit lines is abstracted into an undirected connection graph. Breadth-priority optimization algorithm is applied to search the effective paths between the OD and the flow-matching ratio is acquired by calculating based on multi-factor matching algorithm, in which many relevant numerical examples are analyzed to verify the feasibility of the dual-ratio method and to summarize the characteristics of the project.

scholarly journals Towards bamboo agroforestry development in Ghana: evaluation of crop performance, soil properties and economic benefit

2020 ◽  
Vol 94 (5) ◽  
pp. 1759-1780
Author(s):  
Daniel S. Akoto ◽  
Samuel T. Partey ◽  
Manfred Denich ◽  
Michael Kwaku ◽  
Christian Borgemeister ◽  
...  
Keyword(s):  
Soil Properties ◽  
Deciduous Forest ◽  
Crop Productivity ◽  
Ratio Method ◽  
Cost Ratio ◽  
Financial Benefit ◽  
Forest Zone ◽  
Benefit Cost Ratio ◽  
Woody Perennial ◽  
Set Up

Abstract In the quest to promote bamboo agroforestry in the dry semi-deciduous forest zone of Ghana, we evaluated changes in soil properties, crop productivity and the economic potential of a bamboo-based intercropping system. The intercropping system was established from 3-months old sympodial bamboo (Bambusa balcooa) seedlings planted at a 5 m × 5 m spacing and intercropped with maize, cassava or cowpea. Separate monocropping fields for maize, cassava, cowpea and bamboo were set up adjacent to the intercropped field. In both the intercropping and monocropping fields, plots were with fertilizer treatments and without. The experiment was laid out in a split plot design with four replicates and studied over three years. Economic analysis was conducted using the financial benefit–cost ratio method. The results showed that regardless of fertilizer treatments, bamboo agroforestry and monocropped fields had comparable effects on soil properties and crop productivity within two years of establishment. In the third year, however, bamboo agroforestry had significantly (p < 0.05) higher soil moisture, pH and crop productivity levels. An intercropping advantage over monocropping was evident for all crops with respective partial land equivalent ratios for fertilized and non-fertilized intercropped systems as follows: cowpea (1.37 and 1.54), maize (1.38 and 1.36), and cassava (1.12 and 1.19). The economic evaluation also indicated marginal profitability of bamboo intercropping over monocropping systems. From the results obtained, there are clear indications that where bamboo is a prioritized woody perennial, integrated systems with crops may be encouraged.

scholarly journals Effect of operating conditions on a heavy truck ride comfort with hydro-pneumatic suspension system

2021 ◽  
Vol 304 ◽  
pp. 02011
Author(s):  
Le Xuan Long ◽  
Dang Viet Ha ◽  
Le Van Quynh ◽  
Bui Van Cuong ◽  
Vu Thanh Niem
Keyword(s):  
Ride Comfort ◽  
Surface Condition ◽  
Operating Conditions ◽  
Dump Truck ◽  
Vibration Model ◽  
Pneumatic Suspension ◽  
Heavy Truck ◽  
Set Up ◽  
Mining Dump Truck ◽  
Vehicle Vibration Model

The purpose of this paper is to analyze the performance of the hydro-pneumatic suspension system (HPSs) of a mining dump truck on ride comfort under operating conditions. To achieve goals, a 3-D full-vehicle vibration model of a mining dump truck with 10 degrees of freedom is set up to analyze the effects. A nonlinear mathematical model is set up based on the nonlinear characteristics of the HPSs to determine their vertical force which is connected with a 3-D full-vehicle vibration model. The effects of operating conditions on a heavy truck ride comfort are respectively analyzed through the values of the root mean square of acceleration responses of the vertical cab, pitch and roll angles of cab (awc, awphi and awteta). The analysis results indicate that the survey conditions have a great influence on vehicle ride comfort. Especially, the values of awc, awphi and awteta with the poor road surface condition respectively reduce by 43.1%, 45.9% and 61.8% compared to the very poor road surface condition at vehicle speed of 30 km/h and full load.

scholarly journals Detecting impaired language processing in MCI patients using around-the-ear cEEgrid electrodes

2021 ◽  
Author(s):  
K. Segaert ◽  
C. Poulisse ◽  
R. Markiewicz ◽  
L. Wheeldon ◽  
D. Marchment ◽  
...  
Keyword(s):  
Language Processing ◽  
Language Comprehension ◽  
Daily Living ◽  
Lexical Retrieval ◽  
Clinical Tool ◽  
Cognitive Domains ◽  
Non Invasive ◽  
Word Onset ◽  
Alpha Beta ◽  
Set Up

AbstractMild cognitive impairment (MCI) is the term used to identify those individuals with subjective and objective cognitive decline but with preserved activities of daily living and an absence of dementia. While MCI can impact functioning in different cognitive domains, most notably episodic memory, relatively little is known about the comprehension of language in MCI. In this study we used around-the-ear electrodes (cEEGrids) to identify impairments during language comprehension in MCI patients. In a group of 23 MCI patients and 23 age-matched controls, language comprehension was tested in a two-word phrase paradigm. We examined the oscillatory changes following word onset as a function of lexical retrieval (e.g. swrfeq versus swift) and semantic binding (e.g. horse preceded by swift versus preceded by swrfeq). Electrophysiological signatures (as measured by the cEEGrids) were significantly different between MCI patients and controls. In controls lexical retrieval was associated with a rebound in the alpha/beta range and semantic binding was associated with a post-word alpha/beta suppression. In contrast, both the lexical retrieval and semantic binding signatures were absent in the MCI group. The signatures observed using cEEGrids in controls were comparable to those signatures obtained with a full-cap EEG set-up. Importantly, our findings suggest that MCI patients have impaired electrophysiological signatures for comprehending single-words and multi-word phrases. Moreover, cEEGrids set-ups provide a non-invasive and sensitive clinical tool for detecting early impairments in language comprehension in MCI.

Determination of gross alpha beta surface contamination by handheld equipment

2019 ◽  
Author(s):  
Florinda Cfarku ◽  
Manjola Shyti ◽  
Irma Berdufi ◽  
Polikron Dhoqina ◽  
Elida Bylyku
Keyword(s):  
Surface Contamination ◽  
Gross Alpha ◽  
Alpha Beta

Development of a Thin, Double-Sided Alpha/Beta Detector for Surface-Contamination Measurement

2016 ◽  
Vol 63 (2) ◽  
pp. 634-638 ◽  
Author(s):  
Y. Ifergan ◽  
S. Dadon ◽  
A. Ocherashvili ◽  
I. Israelashvili ◽  
Y. Yehuda-Zada ◽  
...  
Keyword(s):  
Surface Contamination ◽  
Alpha Beta

The phase transition in superconductors III. Phase propagation below the critical field

1954 ◽  
Vol 223 (1153) ◽  
pp. 174-194 ◽  
Keyword(s):  
Eddy Currents ◽  
Surface Condition ◽  
Mean Free Path ◽  
Interphase Surface ◽  
Interesting Phenomenon ◽  
Conservation Of Energy ◽  
Electromagnetic Damping ◽  
Anomalous Skin Effect ◽  
Long Rod ◽  
Set Up

If a superconducting nucleus is created at one end of a long rod of supercooled tin, it grows down to the other end with a velocity, v , of the order of 10 cm sec -1 . This process has been studied experimentally, by winding search coils round the specimens to record the progressive expulsion of the longitudinal magnetic field; in particular v has been measured as a function of field strength and temperature, for a number of specimens of varying radius, conductivity, and surface condition. It is shown that v is governed by the progress of a thin superconducting filament that shoots out from the nucleus along the surface of the specimen. Subsequently this filament closes up to form a sheath of the superconducting phase, leaving some flux enclosed which takes several seconds to escape, but these later stages of the transition are only briefly discussed. A quantitative theory is developed to account for the rate of advance of the original filament, by considering the conditions for conservation of energy during propagation. It is assumed that the two controlling factors are the interphase surface tension and the electromagnetic damping effect of the eddy currents set up in the normal phase ahead of the filament. The theory is complicated by an interesting phenomenon analogous to the anomalous skin effect, which is observed when the electronic mean free path becomes comparable with the filament thickness; a dimensional analysis of the results reveals that the eddy currents may behave ‘classically’, ‘anomalously’, or somewhat between the two, depending on the conditions of the experiment. Only in the anomalous region is the theory completely successful, but its failure elsewhere can be traced to limitations in the rather simple model which is considered. Values of the interphase tension are deduced from the experimental data; these are in agreement with previous estimates based on intermediate state work, but they are more extensive and probably more reliable. They are briefly compared with the predictions of Ginsburg & Landau (1950) and Pippard (1951, 1953).

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