scholarly journals State Assistance with Risk-Based Data Management: Inventory and needs assessment of 25 state Class II Underground Injection Control programs. Phase 1

1992 ◽  
Author(s):  
◽  
2021 ◽  
pp. 875529302198972
Author(s):  
Amin Amirlatifi ◽  
Bijay KC ◽  
Meisam Adibifard ◽  
Farshid Vahedifard ◽  
Ehsan Ghazanfari

The number of recorded earthquakes in Oklahoma has substantially increased during the last few decades, a trend that coincides with the increases in the injected volume in underground injection control (UIC) wells. Several studies have suggested the existence of spatial and temporal links between earthquakes and injection wells. However, creating a spatial connection between the earthquakes and UIC wells requires making a prior assumption about the radius of induced seismicity. In this study, we use intrinsic features of the UIC wells to find the cohort of wells with associated earthquakes, based on the level of activity and proximity of the wells to the events. For this purpose, a hybrid genetic algorithm–K-means (GA-K-means) algorithm was applied over UIC wells, and the geographical representation of the clustered wells was co-visualized with earthquake data to determine wells with induced seismic activities. The analysis was performed every year since 2002, and the most critical attributes to distinguish the behavior of wells were identified. The analysis showed a distinct change in cluster identifiers before the year 2010, which is believed to be the beginning of increased seismic activities, compared to later dates. Our approach was able to group the earthquake-associated wells from the rest of the data, and centroid analysis of these wells helped us identify the critical pressure and cumulative volume range that result in induced seismicity. These findings can be used as guidelines for designing safer injection sites for sustainable energy production in Oklahoma.


2019 ◽  
Vol 90 (2) ◽  
pp. 202-208 ◽  
Author(s):  
Ciara Campbell ◽  
Declan Millett ◽  
Niamh Kelly ◽  
Marie Cooke ◽  
Michael Cronin

ABSTRACT Objective: To compare Phase 1 treatment, using the Frankel 2 (FR2) or the modified Twin Block (MTB), for Class II division 1 malocclusion in children and adolescents with respect to: treatment duration, number of appliance breakages, occlusal outcome, and patient and parent perspectives. Materials and Methods: Sixty participants with a Class II division 1 malocclusion were randomly assigned to either the FR2 or MTB appliance in a two-armed parallel randomized clinical trial with an allocation ratio of 1 to 1. Time to achieve a Class I incisor relationship was the primary outcome. The number of appliance breakages was recorded. The Peer Assessment Rating (PAR) index was used to evaluate pre- and post-treatment occlusal outcome on study models. Participants completed the child OHRQoL (oral health-related quality of life), Piers-Harris, Standard Continuum of Aesthetic Need (SCAN), and Oral Aesthetic Subjective Impact Score (OASIS) questionnaires pre- and post-treatment; parents completed a SCAN questionnaire. Results: Forty-two participants completed treatment (FR2: 20; MTB: 22). Multiple imputation was used to impute missing data for noncompleters. Mean treatment duration was similar for the two appliances (FR2: 376 days [SD 101]; MTB: 340 days [SD 102]; P = .41). There were no significant differences in mean number of appliance breakages (FR2: 0.3 SD 0.7; MTB: 0.4 SD 0.8; P = .67 or mean PAR score P = .48). Patient and parent perspectives did not differ between appliances (P > .05). Conclusions: Phase 1 treatment duration, number of appliance breakages, occlusal outcome, and patient and parent perspectives were similar in 11–14 year olds with Class II division 1 malocclusion treated using the FR2 or MTB appliance.


2015 ◽  
Vol 17 (10) ◽  
pp. 756-759 ◽  
Author(s):  
Tej K. Khalsa ◽  
Norm R.C. Campbell ◽  
Kimbree A. Redburn ◽  
Daniel Lemogoum ◽  
Mark L. Niebylski

Global Heart ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. 25 ◽  
Author(s):  
Liesl J. Zühlke ◽  
David A. Watkins ◽  
Susan Perkins ◽  
Rosemary Wyber ◽  
Jeremiah Mwangi ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document