Motion-Error Immunity In Photo Coordinate Determination-A Novel Approach To The Absolute Comparator

1981 ◽  
Author(s):  
James R. Pekelsky
Keyword(s):  
Motion Error ◽  
Coordinate Determination ◽  
Novel Approach ◽  
The Absolute

scholarly journals A novel approach to Verify air gap and SSD for proton radiotherapy using surface imaging

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Xiao Wang ◽  
Chi Ma ◽  
Rihan Davis ◽  
Rahul R. Parikh ◽  
Salma K. Jabbour ◽  
...  
Keyword(s):  
Body Surface ◽  
Imaging System ◽  
Air Gap ◽  
Surface Imaging ◽  
Proton Radiotherapy ◽  
Optical Surface ◽  
Air Gaps ◽  
Novel Approach ◽  
Proton Treatment ◽  
The Absolute

Abstract Purpose To develop a novel approach to accurately verify patient set up in proton radiotherapy, especially for the verification of the nozzle – body surface air gap and source-to-skin distance (SSD), the consistency and accuracy of which is extremely important in proton treatment. Methods Patient body surfaces can be captured and monitored with the optical surface imaging system during radiation treatment for improved intrafraction accuracy. An in-house software package was developed to reconstruct the patient body surface in the treatment position from the optical surface imaging reference capture and to calculate the corresponding nozzle – body surface air gap and SSD. To validate this method, a mannequin was scanned on a CT simulator and proton plans were generated for a Mevion S250 Proton machine with 20 gantry/couch angle combinations, as well as two different snout sizes, in the Varian Eclipse Treatment Planning Systems (TPS). The surface generated in the TPS from the CT scan was imported into the optical imaging system as an RT Structure for the purpose of validating and establishing a benchmark for ground truth comparison. The optical imaging surface reference capture was acquired at the treatment setup position after orthogonal kV imaging to confirm the positioning. The air gaps and SSDs calculated with the developed method from the surface captured at the treatment setup position (VRT surface) and the CT based surface imported from the TPS were compared to those calculated in TPS. The same approach was also applied to 14 clinical treatment fields for 10 patients to further validate the methodology. Results The air gaps and SSDs calculated from our program agreed well with the corresponding values derived from the TPS. For the phantom results, using the CT surface, the absolute differences in the air gap were 0.45 mm ± 0.33 mm for the small snout, and 0.51 mm ± 0.49 mm for the large snout, and the absolute differences in SSD were 0.68 mm ± 0.42 mm regardless of snout size. Using the VRT surface, the absolute differences in air gap were 1.17 mm ± 1.17 mm and 2.1 mm ± 3.09 mm for the small and large snouts, respectively, and the absolute differences in SSD were 0.81 mm ± 0.45 mm. Similarly, for patient data, using the CT surface, the absolute differences in air gap were 0.42 mm ± 0.49 mm, and the absolute differences in SSD were 1.92 mm ± 1.4 mm. Using the VRT surface, the absolute differences in the air gap were 2.35 mm ± 2.3 mm, and the absolute differences in SSD were 2.7 mm ± 2.17 mm. Conclusion These results showed the feasibility and robustness of using an optical surface imaging approach to conveniently determine the air gap and SSD in proton treatment, providing an accurate and efficient way to confirm the target depth at treatment.

scholarly journals Development of Autonomous Robot Osteotomy for Mandibular Ramal Bone Harvest and Evaluation of Its Accuracy: A Phantom Mandible-Based Trial

2021 ◽  
Vol 11 (6) ◽  
pp. 2885
Author(s):  
Ik Jae Kwon ◽  
Soung Min Kim ◽  
Soon Jung Hwang
Keyword(s):  
Robotic Surgery ◽  
Clinical Application ◽  
Model Experiment ◽  
Autonomous Robot ◽  
Light Weight ◽  
Mean Values ◽  
Phantom Model ◽  
Coordinate Determination ◽  
The Absolute

An autonomous robot osteotomy using direct coordinate determination for registering was developed, and the accuracy of the designed osteotomy along the preprogrammed plan was evaluated. Furthermore, the accuracy of the robotic and manual osteotomy was compared in regard to cut position, length, angle and depth. A light-weight robot was used in this study, with an electric gripper. Twenty stone models were used to evaluate accuracy of osteotomy and sixteen mandible phantoms were used to simulate the ramal bone harvest osteotomy for comparison between robotic and manual surgery. In the stone model experiment, the absolute mean values for osteotomy errors for position, length, angle, and depth were 0.93 ± 0.45 mm, 0.81 ± 0.34 mm, 1.26 ± 1.35°, and 1.19 ± 0.73 mm, respectively. In the mandible phantom model experiment, the robotic surgery showed lower errors for position, length and angle (0.70 ± 0.34 mm, 0.35 ± 0.19 mm and 1.32 ± 0.96°) and somewhat higher errors for depth (0.59 ± 0.46 mm) than manual surgery (1.83 ± 0.65 mm, 0.62 ± 0.37 mm, 5.96 ± 3.47° and 0.40 ± 0.31 mm). This study may provide a basis for developing clinical application of an autonomous robot osteotomy.

The development of a novel approach for assessment of the first flush in urban stormwater discharges

2010 ◽  
Vol 61 (10) ◽  
pp. 2681-2688 ◽  
Author(s):  
P. M. Bach ◽  
D. T. McCarthy ◽  
A. Deletic
Keyword(s):  
Weighted Average ◽  
Quality Data ◽  
Background Concentration ◽  
First Flush ◽  
Storm Events ◽  
Sensitivity Testing ◽  
Water Quality Data ◽  
Runoff Volume ◽  
Novel Approach ◽  
The Absolute

The management of stormwater pollution has placed particular emphasis on the first flush phenomenon. However, definition and current methods of analyses of the phenomena contain serious limitations, the most important being their inability to capture a possible impact of the event size (total event volume) on the first flush. This paper presents the development of a novel approach in defining and assessing the first flush that should overcome these problems. The phenomenon is present in a catchment if the decrease in pollution concentration with the absolute cumulative volume of runoff from the catchment is statistically significant. Using data from seven diverse catchments around Melbourne, Australia, changes in pollutant concentrations for Total Suspended Solids (TSS) and Total Nitrogen (TN) were calculated over the absolute cumulative runoff and aggregated from a collection of different storm events. Due to the discrete nature of the water quality data, each concentration was calculated as a flow-weighted average at 2 mm runoff volume increments. The aggregated concentrations recorded in each increment (termed as a ‘slice’ of runoff) were statistically compared to each other across the absolute cumulative runoff volume. A first flush is then defined as the volume at which concentrations reach the ‘background concentration’ (i.e. the statistically significant minimum). Initial results clearly highlight first flush and background concentrations in all but one catchment supporting the validity of this new approach. Future work will need to address factors, which will help assess the first flush's magnitude and volume. Sensitivity testing and correlation with catchment characteristics should also be undertaken.

scholarly journals A Novel Approach for the Detection of Developing Thunderstorm Cells

2018 ◽  
Author(s):  
Richard Mueller ◽  
Matthias Jerg ◽  
Stephane Haussler ◽  
Dirk Heizenreder
Keyword(s):  
Water Vapor ◽  
Brightness Temperature ◽  
Vector Product ◽  
Absolute Value ◽  
Convective Clouds ◽  
Critical Success ◽  
Novel Approach ◽  
Forecast Lead Time ◽  
The Absolute ◽  
Atmospheric Motion Vectors

This study presents a novel approach for the early detection of developing thunderstorms. To date, methods for the detection of developing thunderstorms usually rely on accurate atmospheric motion vectors (AMVs) for the estimation of cooling rate of convective clouds, which corresponds to the updraft strength of the cloud objects. In this study we present a method for the estimation of the updraft strength that does not rely on AMVs. The updraft strength is derived directly from the satellite observations in the SEVIRI water vapor channels. For this purpose the absolute value of the vector product of two vectors derived from the observed radiances emitted by the water vapor channels in 2 subsequent satellite images is calculated. The x and y components of the vectors consists of the temporal change of the spatial brightness temperature gradients in x- and y-direction, the z component consists of the temporal variation of the brightness temperature at pixel level. The absolute value of the vector product is referred to as normalized updraft strength (NUS). The performance of the method has been investigated for 2 summer periods in 2016 and 2017 by validation with lightning data. Values of the Critical Success Index (CSI) of about 66 % for the 2016 period and 62 % for the 2017 period demonstrate the good performance of the method. The POD values for the experiments with the highest CSI values are 90.3 for 2016 period and 87.6 for the 2017 period, respectively The corresponding FAR values are 28.2% (2016) and 32.5 % (2017), respectively. In summary, the method has the potential to reduce the forecast lead time significantly, and can be quite useful in regions without a well maintained radar network.

Hotel daily occupancy forecasting with competitive sets: a recursive algorithm

2016 ◽  
Vol 28 (2) ◽  
pp. 267-285 ◽  
Author(s):  
Zvi Schwartz ◽  
Muzaffer Uysal ◽  
Timothy Webb ◽  
Mehmet Altin
Keyword(s):  
Revenue Management ◽  
Data Sharing ◽  
Strong Support ◽  
Empirical Support ◽  
Essential Element ◽  
Unique Contribution ◽  
Individual Property ◽  
Content Type ◽  
Novel Approach ◽  
The Absolute

Purpose – This paper aims to improve the accuracy of hotel daily occupancy forecasts – an essential element in the revenue management cycle – by proposing and testing a novel approach. The authors add the hotel competitive-set’s predicted occupancy as an input of the individual property forecast and, using a recursive approach, demonstrate that there is a potential for significant reduction in the forecasting error. Design/methodology/approach – The paper outlines the theoretical justification and the mechanism for this new approach. It applies a simulation for exploring the potential to improve the accuracy of the hotel’s daily occupancy forecasts, as well as analysis of data from a field study of two hotel clusters’ daily forecasts to provide empirical support to the procedure’s viability. Findings – The results provide strong support to the notion that the accuracy could be enhanced. Incorporating the competitive set prediction by using either a genetic algorithm or the simple linear regression model improves the accuracy of the forecast using either the absolute or the absolute percentage as the error measure. Research limitations/implications – The proliferation of data sharing practices in the hotel industry reveals that the timely data sharing-aggregation-dissemination mechanism required for implementing this forecasting paradigm is feasible. Originality/value – Given the crucial role of accurate forecasts in revenue management and recent changes in the hotels’ operating environment which made it harder to achieve or maintain high levels of accuracy, this study’s proposed novel approach has the potential to make a unique contribution in the realm of forecasting daily occupancies.

Assessment of coulometric array electrochemical detection coupled with HPLC-UV for the absolute quantitation of pharmaceuticals

The Analyst ◽  
2017 ◽  
Vol 142 (3) ◽  
pp. 525-536 ◽  
Author(s):  
Michael B. Hicks ◽  
Leah Salituro ◽  
Ian Mangion ◽  
Wes Schafer ◽  
Rong Xiang ◽  
...  
Keyword(s):  
Electrochemical Detection ◽  
Array Detector ◽  
Absolute Quantitation ◽  
Faraday’S Law ◽  
Novel Approach ◽  
Flow Through ◽  
Electrochemical Redox ◽  
The Absolute ◽  
Redox Conversion

A novel approach for the absolute quantitation of pharmaceuticals without standards using a flow-through coulometric array detector and the known electrochemical redox conversion applying Faraday's law,Q=N/Fn.

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