scholarly journals The Simulation of In-Situ Groundwater Detector Response as a Means of Identifying Beta Emitting Radionuclides by Linear Regression Analysis

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5732
Author(s):  
Graeme Turkington ◽  
Kelum A. A. Gamage ◽  
James Graham

The in-situ characterisation of strontium-90 contamination of groundwater at nuclear decommissioning sites would represent a novel and cost-saving technology for the nuclear industry. However, beta particles are emitted over a continuous spectrum and it is difficult identify radionuclides due to the overlap of their spectra and the lack of characteristic features. This can be resolved by using predictive modelling to perform a maximum-likelihood estimation of the radionuclides present in a beta spectrum obtained with a semiconductor detector. This is achieved using a linear least squares linear regression and relating experimental data with simulated detector response data. In this case, by simulating a groundwater borehole scenario and the deployment of a cadmium telluride detector within it, it is demonstrated that it is possible to identify the presence of 90Sr, 90Y, 137Cs and 235U decay. It is determined that the optimal thickness of the CdTe detector for this technique is in the range of 0.1 to 1 mm. The influence of suspended solids in the groundwater is also investigated. The average and maximum concentrations of suspended particles found at Sellafield do not significantly deteriorate the results. It is found that applying the linear regression over two energy windows improves the estimate of 90Sr activity in a mixed groundwater source. These results provide validation for the ability of in-situ detectors to determine the activity of 90Sr in groundwater in a timely and cost-effective manner.


2019 ◽  
Vol 4 (2) ◽  
pp. 17
Author(s):  
Dedy Mulyadi ◽  
Didik Purwanto

The question of compensation in addition to sensitive to be driving someone to worl due to an effect on morale and discipline employees. Therefore , any  agency or any organization should be able to provide compensation equal to the workload  to create a workforce that efficient and effective manner can be realized. Amaore than that, the company’s goal to improve performance. Performance assessment is a subjective process that involves human judgments. Thus, performance assessment is very likely wrong and very easily influonced by sources that are not actual, so it must be taken into account and considered reasinable. Frformance appraisals are considered  to meet the target if it has a good impact on new employees who rated their performance. Simple linear regression analysis using SPSS version 12:00 data processing obtained tegression equation Y = 0,487 X 74 + with an explanation of X = award, 74 = constant, 0.487 = coefficient awards, and Y = performance based on simple linear regression equation in case of increase of one unit of the  performance award will be increased 0.487 units. If company policy negates the performance award will remain at a constant rate (74) units . (A) Test results obtained thitung significant constants of (12.574) > t table for (1.960 then reject Ho constanta significant meaning. (B) significant Test award coefficient t count the results obtained by (2.164)> t table foe (1.96) then reject Ho the mean coeffent of appreciation affect the performance . (C) correlation coefficient analysis is done by calculating the product moment corration (pearson)  to test  whether or not a strong  relationship between the variables X  dan Y , based on the results of cakculations with SPSS  table valuse obtained by calculating the  correlation coefficient r (0.3100> r on the table for a = 0,05 (0.291) then reject Ho, which means there is a relationship of respect for performance. When we enter these valuse in the table shows the interpretation of the correlation coefficient between the interval from 0.20 to 0.399 which has a low relationship



2021 ◽  
Author(s):  
Abdelhak Ladmia ◽  
Dr. Younes bin Darak Al Blooshi ◽  
Abdullah Alobedli ◽  
Dragoljub Zivanov ◽  
Myrat Kuliyev ◽  
...  

Abstract The expected profiles of the water produced from the mature ADNOC fields in the coming years imply an important increase and the OPEX of the produced and injected water will increase considerably. This requires in-situ water separation and reinjection. The objective of in-situ fluid separation is to reduce the cost of handling produced water and to extend the well natural flow performance resulting in increased and accelerated production. The current practice of handling produced water is inexpensive in the short term, but it can affect the operating cost and the recovery in the long term as the expected water cut for the next 10-15 years is forecasted to incease significantly. A new water management tool called downhole separation technology was developed. It separates oil and & gas from associated water inside the wellbore to be reinjected back into the disposal wells. The Downhole Oil Water Separation (DHOWS) Technology is one of the key development strategies that can reduce considerable amounts of produced water, improve hydrocarbon recovery, and minimize field development cost by eliminating surface water treatment and handling costs. The main benefits of DHOWS include acceleration of oil offtake, reduction of production cost, lessening produced water volumes, and improved utilization of surface facilities. In effect, DHOWS technologies require specific design criteria to meet the objectives of the well. Therefore, multi--discipline input data are needed to install an effective DHOWS with a robust design that economically outperforms and boosts oil and/or gas productions. This paper describes the fundamental criteria and workflow for selecting the most suitable DHOWS design for new and sidetracked wells to deliver ADNOC production mandates in a cost-effective manner while meeting completion requirements and adhering to reservoir management guidelines.



2003 ◽  
Vol 1819 (1) ◽  
pp. 314-322
Author(s):  
Bruce S. Morton ◽  
Alex T. Visser ◽  
Emile Horak

Low-volume and unpaved roads constitute the majority of the road network throughout the developing and developed world. Upgrading these unpaved roads to conform to standards of low-volume flexible asphalt pavements is a costly exercise. In most instances, this involves constructing an entirely new pavement base. Recent technological advances in the field of deep in situ recycling have provided pavement engineers with an alternative to standard rehabilitation and reconstruction methods of flexible pavements. One such technique of stabilization is foamed tar treatment of inferior natural pavement materials through the application of deep in situ recycling to produce a stabilized base for lowvolume flexible pavements. Foamed tar technology and the concept of deep in situ recycling, and its advantages over current reconstruction methods, were reviewed. Health aspects relating to implementation of the stabilization process were addressed with respect to the use of gasifier tar in a controlled recycling environment. The engineering properties of foamed tar mixes were compared with existing stabilization techniques. A test section was constructed with particular attention to the flexibility of foamed tar for placement time, workability, and durability to environmental conditions. Performance testing results were analyzed. In conclusion, the benefits of foamed tar stabilization for developing an improved road network in a cost-effective manner were evaluated.



Author(s):  
C. N. Edmonds ◽  
C. P. Green ◽  
I. E. Higginbottom

AbstractSoluble carbonate rocks often pose a subsidence hazard to engineering and building works, due to the presence of either metastable natural solution features or artificial cavities. There is also an inherent danger to the public and lives have been lost because of unexpected ground collapses. Although site investigation techniques are becoming increasingly elaborate, the detection of hazardous ground conditions associated with limestones is frequently difficult and unreliable. Remedial measures to solve subsidence problems following foundation failure are expensive. It would be advantageous if areas liable to subsidence could be identified in a cost-effective manner in advance of planning and ground investigation. Hazard mapping could then be used by planners when checking the geotechnical suitability of a proposed development or by engineering geologists/geotechnical engineers to design the type of ground investigation best suited to the nature and scale of the potential hazard.Recent research focussed on the English Chalk outcrop has led to the development of two new models to predict the subsidence hazard for both natural solution features and artificial cavities. The predictive models can be used to map the hazard at any given chalkland locality, as a cost-effective precursor to ground investigation. The models, although created for the Chalk outcrop, have important implications for all types of limestone terrain.The basis of the predictive modelling procedure is an analysis of the spatial distribution of nearly 1600 natural solution features, and more than 850 artificial cavity locations, identified from a wide varietyy of sources, including a special appeal organized by CIRIA. A range of geological, hydrogeological and geomorphological factors are evaluated to identify significant relationships with subsidence. These factors are ranked, numerically weighted and incorporated into two quantitative subsidence hazard model formulae. The models can be applied to perform hazard mapping.



Author(s):  
Alan D. Chockie ◽  
M. Robin Graybeal ◽  
Scott D. Kulat

The risk-informed inservice inspection (RI-ISI) process provides a structured and systematic framework for allocating inspection resources in a cost-effective manner while improving plant safety. It helps focus inspections where failure mechanisms are likely to be and where enhanced inspections are warranted. To date, over eighty-five percent of US nuclear plants and a number of non-US plants have implemented, or are in the process of implementing, RI-ISI programs. Many are already involved in the periodic update of their RI-ISI program. The development of RI-ISI methodologies in the US has been a long and involved process. The risk-informed procedures and rules were developed to take full advantage of PRA data, industry and plant experiences, information on specific damage mechanisms, and other available information. An important feature of the risk-informed methodologies is the requirement to make modifications and improvements to the plant’s RI-ISI application as new information and insights become available. The nuclear industry, ASME Section XI, and the Nuclear Regulatory Commission have all worked together to take advantage of the lessons learned over the years to refine and expand the use of risk-informed methodologies. This paper examines the lessons learned and the benefits received from the application and refinement of risk-informed inservice inspection programs. Also included in the paper is a review of how the information and insights have been used to improve the risk-informed methodologies.



2021 ◽  
Author(s):  
Anwarudin Saidu Mohamed ◽  
Syafiq Effendi Jalis ◽  
Intiran Raman ◽  
Kumanan Sanmugam ◽  
Dhanaraj Turunawarasu ◽  
...  

Abstract Hydrate occurrence is synonymous in deep water wells, notably when the well experience significant reduction in fluid temperature during production. Hence, the operating philosophy must take into consideration the ability to maintain the well-fluid outside the hydrate or wax phase envelope and ensure the contingencies are in place to mitigate any plug, deposit or gel formation. This paper illustrates the characterization of hydrate and wax plug encountered and devise of innovative solution to remediate the blockage in two wells in Sabah waters which were plugged due to cooling of the wells during an unplanned shut down. The solution devised is to set precedence to manage temperature dependent blockages in similar Deepwater wells or facilities. Hydrate and wax models were created to predict blockage severity and its location. Nodal analysis was used to model thermodynamic equilibrium at target location of the plug where the temperature is below the melting point and ultimately to predict the required heat to dissolve the blockages. A Thermo-chemical system was identified, selected, and customized and then injected into well to ensure the temperature generated at the location of the plug was above the melting point of hydrate and wax. Thermo-chemical injection was identified as a viable method of In-situ Heat Generating Technique to generate heat at desired location. The chemical solution was injected via capillary tubing to transmit the heat via conduction and convection to melt the hydrate and paraffinic plug in these 2 wells. An arriving temperature of 40°C at the target zones was required to melt the plug. A positive pressure was maintained in the production tubing during chemical injection to avoid rapid pressure increase as the hydrate plugs dissolved. A temperature of 100 °C was recorded at the wellhead throughout the injection. The downhole gauge indicated positive response, suggesting the heat generated transmitted effectively. After a short duration of injection, communication was established. Hydrate inhibitor was injected to secure the well prior to unloading. The wells were successfully relieved and stabilized production of 1,200 bopd and 800 bopd respectively. The simulation was redesigned based on data collected from the operation to improve the model and to be used for future works. The ability to integrate laboratory analysis, computer aided simulation and operational data was integral to this paper demonstrating an effective way to characterize temperature dependent blockages in production system. Design of experiments provided better insight to address the problem. Innovative use of novel chemistry to produce heat, in-situ heat solved hydrate and wax related issues in a most cost-effective manner. The process of customizing a chemical system based on laboratory and simulation results was effective in ensuring delivery of the results. The bull-heading operation to inject the chemical system proved to be a cost-effective remedial method to unlock the barrels and can be considered preventive or as a contingency measure in dealing with temperature dependent blockages or plugs in future.





Author(s):  
Eka Ambara Harci Putranta ◽  
Lilik Ambarwati

The study aims to analyze the influence of internal banking factors in the form of: Capital Adequency Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing at Sharia Banks. This research method used multiple linear regression analysis with the help of SPSS 16.00 software which is used to see the influence between the independent variables in the form of Capital Adequacy Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing. The sample of this study was 3 Islamic Commercial Banks, so there were 36 annual reports obtained through purposive sampling, then analyzed using multiple linear regression methods. The results showed that based on the F Test, the independent variable had an effect on the NPF, indicated by the F value of 17,016 and significance of 0,000, overall the independent variable was able to explain the effect of 69.60%. While based on the partial t test, showed that CAR has a significant negative effect, Total assets have a significant positive effect with a significance value below 0.05 (5%). Meanwhile FDR does not affect NPF.



Author(s):  
Muhammad Rois Rois ◽  
Manarotul Fatati Fatati ◽  
Winda Ihda Magfiroh

This study aims to determine the effect of Inflation, Exchange Rate and Composite Stock Price Index (IHSG) to Return of PT Nikko Securities Indonesia Stock Fund period 2014-2017. The study used secondary data obtained through documentation in the form of PT Nikko Securities Indonesia Monthly Net Asset (NAB) report. Data analysis is used with quantitative analysis, multiple linear regression analysis using eviews 9. Population and sample in this research are PT Nikko Securities Indonesia. The result of multiple linear regression analysis was the coefficient of determination (R2) showed the result of 0.123819 or 12%. This means that the Inflation, Exchange Rate and Composite Stock Price Index (IHSG) variables can influence the return of PT Nikko Securities Indonesia's equity fund of 12% and 88% is influenced by other variables. Based on the result of the research, the variables of inflation and exchange rate have a negative and significant effect toward the return of PT Nikko Securities Indonesia's equity fund. While the variable of Composite Stock Price Index (IHSG) has a negative but not significant effect toward Return of Equity Fund of PT Nikko Securities Indonesia



Liquidity ◽  
2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Yanti Budiasih

The objectives of this study are to analyze changes in organizational structure, job design, organizational culture and its influence on employee productivity at PT. XX in Jakarta and to identify variables that have a dominant influence on the productivity of employees. The research method used is using multiple linear regression analysis. The results show that the all variables simultaneously and partially change the organizational structure, job design, and organizational culture has a significant impact on employee productivity at PT. XXin Jakarta.



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