scholarly journals Land Subsidence Prediction using Recurrent Neural Networks

Author(s):  
Sunil Kumar ◽  
Dheeraj Kumar ◽  
Praveen Kumar Donta ◽  
Tarachand Amgoth

Abstract In an environment, one of the natural geological hazards is land surface subsidence. There are several reasons for land subsidence among them are underground coal mining and coal fire in subsurface or deformation is primarily measured in terms of change in ground elevation values ( Z-dimension) at different time intervals at identified ground locations. All the conventional and exiting techniques have certain limitations in monitoring and predicting land surface subsidence. In this work, we predict the land subsidence for one year in the interval of twelve days on the datasets collected through a monitoring technique called Modified PSInSAR. The sample datasets contains 14 locations and 67 previous land subsidence value calculated from each location. We train and test predictive models and perform the prediction of the land subsidence using Vanilla and Stacked long short-term memories (LSTMs). Finally, we demonstrates the predicted deformation values of the 14 locations for one year.

Author(s):  
Yi Liu ◽  
Jiang Li ◽  
Zheng N. Fang ◽  
Mojtaba Rashvand ◽  
Tranell Griffin

Abstract. The combination of groundwater withdrawal, hydrocarbon extraction, salt-dome movement and faulting have caused widespread subsidence in the Houston-Galveston region (HGR). Subsidence results from primary consolidation consisting of inelastic (nonrecoverable) and elastic (recoverable) compaction caused by subsurface fluid withdrawal and secondary consolidation (creep) over time caused by overburden pressure. Subsidence in the HGR is monitored using borehole extensometers that were installed at 13 locations across Harris and Galveston counties between 1962 and 1980. By 1977, withdrawals from the Chicot and Evangeline aquifers resulted in groundwater-level declines of about 114 and 115 m relative to predevelopment water levels, respectively in parts of Harris County. By 1979, as much as 3 m of land subsidence was estimated to have occurred in localized areas of the HGR. Land subsidence can be hazardous in populated areas because it exacerbates the effects of storm surge and impedes storm-water runoff by decreasing land-surface elevations in areas where water accumulates. To assess aquifer compaction in response to changes in groundwater levels, a bulk land-surface subsidence rate is assumed to be the sum of the primary consolidation rate and the negligibly variable component of overburden pressure referred to as the “pseudo-constant secondary consolidation rate.” From 1931 to 1976, groundwater levels decreased as groundwater withdrawal rates increased from 0.57 to 4.3 million m3 d−1, causing pressure heads in aquitards the Chicot and Evangeline aquifers to continually decline. In response to reductions in groundwater withdrawal rates from 4.3 to 3.0 million m3 d−1 between 1976 and 2001, groundwater levels rebounded, decreasing inelastic compaction rates in some parts of the HGR from as much as about 40 mm yr−1 in the early 1980s to negligible amounts by 2000. Inelastic consolidation from about 1937 to 2000 contributed to land-surface subsidence and its associated effects. Land-surfaces have rebounded in localized areas of the HGR where groundwater levels rebounded significantly. Pseudo-constant secondary consolidation rates were computed at each of the 13 extensometers and ranged from 0.48 to 8.49 mm yr−1 in areas where groundwater levels in the two aquifers were stabilizing. This secondary consolidation subsidence is beyond the control of any groundwater-level management schemes because it is caused by geohistorical overburden pressure on the two aquifers.


VASA ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 120-124 ◽  
Author(s):  
Asciutto ◽  
Lindblad

Background: The aim of this study is to report the short-term results of catheter-directed foam sclerotherapy (CDFS) in the treatment of axial saphenous vein incompetence. Patients and methods: Data of all patients undergoing CDFS for symptomatic primary incompetence of the great or small saphenous vein were prospectively collected. Treatment results in terms of occlusion rate and patients’ grade of satisfaction were analysed. All successfully treated patients underwent clinical and duplex follow-up examinations one year postoperatively. Results: Between September 2006 and September 2010, 357 limbs (337 patients) were treated with CDFS at our institution. Based on the CEAP classification, 64 were allocated to clinical class C3 , 128 to class C4, 102 to class C5 and 63 to class C6. Of the 188 patients who completed the one year follow up examination, 67 % had a complete and 14 % a near complete obliteration of the treated vessel. An ulcer-healing rate of 54 % was detected. 92 % of the patients were satisfied with the results of treatment. We registered six cases of thrombophlebitis and two cases of venous thromboembolism, all requiring treatment. Conclusions: The short-term results of CDFS in patients with axial vein incompetence are acceptable in terms of occlusion and complications rates.


2018 ◽  
Vol 2 (S1) ◽  
pp. e000125
Author(s):  
Khyati Vaja ◽  
Mukesh Suvera

Aims and Objectives: To know the most common surgical problems in pediatric patients presented with inguino-scrotal swellings and management done routinely. Methodology: This study was carried out in the department of general surgery, Sharadaben hospital and pediatric surgery of VS hospital, Ahmedabad. The cases were studied for a period of about one year (January, 2017 to Dec, 2017) and all children below 12 years of age, presenting to us with inguinoscrotal swellings were included in this study. The information was analysed in terms of age, diagnosis, procedure carried out and outcome. Results: Amongst the 150 children under the age of 12 years, 143 patients were males and 7 were females. Among these 150, 52 cases were of hydrocoele, 70 cases of hernia (of which 63 were males and 7 were females), 25 cases of undescended testis and 3 cases of epididymo orchitis were documented. All cases underwent simple herniotomy for hernia and hydrocoele, orchidopexy for undescended testis. The length of hospital stay ranged from 2-4 days with mean of 2.46 days. 11 children in the study were documented to have short term complications, all of which were recognised in the hospital and managed with good results. Conclusion: Hernia and Hydrocoele in children are often congenital and diagnosed clinically (history and examination). Indirect inguinal hernia are more common than other groin hernias. Open herniotomy is the operation of choice for inguinal hernia in children.


Diabetes ◽  
1984 ◽  
Vol 33 (10) ◽  
pp. 995-1001 ◽  
Author(s):  
K. Perlman ◽  
R. M. Ehrlich ◽  
R. M. Filler ◽  
A. M. Albisser

1989 ◽  
Vol 20 (3) ◽  
pp. 119-128 ◽  
Author(s):  
N. Bhana

The objective of this study is to determine whether companies listed on the Johannesburg Stock Exchange overreacted to unexpected favourable and unfavourable company-specific news events during the period 1970 - 1984. The JSE appears to be inefficient in reacting to the announcement of unfavourable news; economically significant abnormal returns up to one year following the event are observed. The JSE does not appear to overreact to news of a favourable nature, there is only weak evidence of short-term overreaction. The selling pressure caused by panic selling could depress prices well below levels justified by the unfavourable news. The magnitude of the overreaction to unfavourable news is sufficient to enable astute investors to outperform the market by taking positions in these securities. Knowledge of the pattern of market overreaction can also be of value to investors for transactions that are to take place anyway.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Mohamed El ghazeery ◽  
Mohamed Elsawaf ◽  
Mohamed Ashour ◽  
Mohamed Metwaly ◽  
Mohamed Hashish

Abstract Background Adolescent obesity is an important health issue. Non-surgical weight management programs, even the most aggressive, have shown modest weight reduction results. Laparoscopic sleeve gastrectomy (LSG) is gaining reliability as a low surgical risk bariatric procedure with proper efficiency for this age group. The aim of this study was to present our initial experience with LSG in morbidly obese adolescents and to report short-term clinical and metabolic outcome. Results Mean age was 16.43 years, and mean preoperative weight and body mass index (BMI) were 132.68 kg and 48.90 respectively. Mean excess weight loss (EWL) was 54.11 kg 1 year after LSG, corresponding to 74 EWL% as well as mean BMI loss (BML) of 19.89. LSG improved fatty infiltration of the liver in 75% of cases and other comorbidities in 100% of patients. Conclusions LSG proved to be a safe procedure with significant short-term clinical and metabolic success for adolescent obesity.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Isabela Floriano ◽  
Elizabeth Souza Rocha ◽  
Ronilza Matos ◽  
Juliana Mattos-Silveira ◽  
Kim Rud Ekstrand ◽  
...  

Abstract Background Few studies have addressed the clinical parameters' predictive power related to caries lesion associated with their progression. This study assessed the predictive validity and proposed simplified models to predict short-term caries progression using clinical parameters related to caries lesion activity status. Methods The occlusal surfaces of primary molars, presenting no frank cavitation, were examined according to the following clinical predictors: colour, luster, cavitation, texture, and clinical depth. After one year, children were re-evaluated using the International Caries Detection and Assessment System to assess caries lesion progression. Progression was set as the outcome to be predicted. Univariate multilevel Poisson models were fitted to test each of the independent variables (clinical features) as predictors of short-term caries progression. The multimodel inference was made based on the Akaike Information Criteria and C statistic. Afterwards, plausible interactions among some of the variables were tested in the models to evaluate the benefit of combining these variables when assessing caries lesions. Results 205 children (750 surfaces) presented no frank cavitations at the baseline. After one year, 147 children were reassessed (70%). Finally, 128 children (733 surfaces) presented complete baseline data and had included primary teeth to be reassessed. Approximately 9% of the reassessed surfaces showed caries progression. Among the univariate models created with each one of these variables, the model containing the surface integrity as a predictor had the lowest AIC (364.5). Univariate predictive models tended to present better goodness-of-fit (AICs < 388) and discrimination (C:0.959–0.966) than those combining parameters (AIC:365–393, C:0.958–0.961). When only non-cavitated surfaces were considered, roughness compounded the model that better predicted the lesions' progression (AIC = 217.7, C:0.91). Conclusions Univariate model fitted considering the presence of cavitation show the best predictive goodness-of-fit and discrimination. For non-cavitated lesions, the simplest way to predict those lesions that tend to progress is by assessing enamel roughness. In general, the evaluation of other conjoint parameters seems unnecessary for all non-frankly cavitated lesions.


1986 ◽  
Vol 16 (1) ◽  
pp. 65-70 ◽  
Author(s):  
L. K. George Hsu ◽  
Diane Holder

SynopsisFifty-six bulimia nervosa patients were treated by means of a behavioural approach and followed for at least one year after completion or dropping out of treatment. Outcome was encouraging in about half of the patients and several psychiatric indicators, such as duration of illness and response to treatment, were identified. The significance of the findings and unresolved methodological issues are discussed.


2011 ◽  
Vol 8 (9) ◽  
pp. 2815-2831 ◽  
Author(s):  
W. Eugster ◽  
T. DelSontro ◽  
S. Sobek

Abstract. Greenhouse gas budgets quantified via land-surface eddy covariance (EC) flux sites differ significantly from those obtained via inverse modeling. A possible reason for the discrepancy between methods may be our gap in quantitative knowledge of methane (CH4) fluxes. In this study we carried out EC flux measurements during two intensive campaigns in summer 2008 to quantify methane flux from a hydropower reservoir and link its temporal variability to environmental driving forces: water temperature and pressure changes (atmospheric and due to changes in lake level). Methane fluxes were extremely high and highly variable, but consistently showed gas efflux from the lake when the wind was approaching the EC sensors across the open water, as confirmed by floating chamber flux measurements. The average flux was 3.8 ± 0.4 μg C m−2 s−1 (mean ± SE) with a median of 1.4 μg C m−2 s−1, which is quite high even compared to tropical reservoirs. Floating chamber fluxes from four selected days confirmed such high fluxes with 7.4 ± 1.3 μg C m−2 s−1. Fluxes increased exponentially with increasing temperatures, but were decreasing exponentially with increasing atmospheric and/or lake level pressure. A multiple regression using lake surface temperatures (0.1 m depth), temperature at depth (10 m deep in front of the dam), atmospheric pressure, and lake level was able to explain 35.4% of the overall variance. This best fit included each variable averaged over a 9-h moving window, plus the respective short-term residuals thereof. We estimate that an annual average of 3% of the particulate organic matter (POM) input via the river is sufficient to sustain these large CH4 fluxes. To compensate the global warming potential associated with the CH4 effluxes from this hydropower reservoir a 1.3 to 3.7 times larger terrestrial area with net carbon dioxide uptake is needed if a European-scale compilation of grasslands, croplands and forests is taken as reference. This indicates the potential relevance of temperate reservoirs and lakes in local and regional greenhouse gas budgets.


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