scholarly journals CO2 migration in saline aquifers. Part 2. Capillary and solubility trapping

2011 ◽  
Vol 688 ◽  
pp. 321-351 ◽  
Author(s):  
C. W. MacMinn ◽  
M. L. Szulczewski ◽  
R. Juanes
Keyword(s):  
Large Scale ◽  
Complete Solution ◽  
Saline Aquifers ◽  
Buoyant Plume ◽  
Storage Efficiency ◽  
Capillary Trapping ◽  
Sloping Aquifer ◽  
Promising Tool ◽  
Solubility Trapping ◽  
The Impact

AbstractThe large-scale injection of carbon dioxide (CO2) into saline aquifers is a promising tool for reducing atmospheric CO2 emissions to mitigate climate change. An accurate assessment of the post-injection migration and trapping of the buoyant plume of CO2 is essential for estimates of storage capacity and security, but these physical processes are not fully understood. In Part 1 of this series, we presented a complete solution to a theoretical model for the migration and capillary trapping of a plume of CO2 in a confined, sloping aquifer with a natural groundwater through-flow. Here, we incorporate solubility trapping, where CO2 from the buoyant plume dissolves into the ambient brine via convective mixing. We develop semi-analytical solutions to the model in two limiting cases: when the water beneath the plume saturates with dissolved CO2 very slowly or very quickly (‘instantaneously’) relative to plume motion. We show that solubility trapping can greatly slow the speed at which the plume advances, and we derive an explicit analytical expression for the position of the nose of the plume as a function of time. We then study the competition between capillary and solubility trapping, and the impact of solubility trapping on the storage efficiency, a macroscopic measure of plume migration. We show that solubility trapping can increase the storage efficiency by several-fold, even when the fraction of CO2 trapped by solubility trapping is small.

scholarly journals CO2 migration in saline aquifers. Part 1. Capillary trapping under slope and groundwater flow

2010 ◽  
Vol 662 ◽  
pp. 329-351 ◽  
Author(s):  
C. W. MACMINN ◽  
M. L. SZULCZEWSKI ◽  
R. JUANES
Keyword(s):  
Groundwater Flow ◽  
Complete Solution ◽  
Specific Capacity ◽  
Trapping Efficiency ◽  
Storage Efficiency ◽  
Capillary Trapping ◽  
Promising Tool ◽  
Plume Migration ◽  
And Migration ◽  
The Impact

Injection of carbon dioxide (CO2) into geological formations is widely regarded as a promising tool for reducing global atmospheric CO2 emissions. To evaluate injection scenarios, estimate reservoir capacity and assess leakage risks, an accurate understanding of the subsurface spreading and migration of the plume of mobile CO2 is essential. Here, we present a complete solution to a theoretical model for the subsurface migration of a plume of CO2 due to natural groundwater flow and aquifer slope, and subject to residual trapping. The results show that the interplay of these effects leads to non-trivial behaviour in terms of trapping efficiency. The analytical nature of the solution offers insight into the physics of CO2 migration, and allows for rapid, basin-specific capacity estimation. We use the solution to explore the parameter space via the storage efficiency, a macroscopic measure of plume migration. In a future study, we shall incorporate CO2 dissolution into the migration model and study the importance of dissolution relative to capillary trapping and the impact of dissolution on the storage efficiency.

Urban Regeneration in London Docklands: A Five-Year Policy Review

1988 ◽  
Vol 6 (2) ◽  
pp. 187-208 ◽  
Author(s):  
A Church
Keyword(s):  
Urban Development ◽  
Labour Market ◽  
Urban Areas ◽  
Large Scale ◽  
Central Government ◽  
Complete Solution ◽  
Local Economy ◽  
Development Corporation ◽  
The Impact ◽  
London Docklands

An urban development corporation was established in London Docklands in 1981. Recently, central government has announced its intention to set up similar organisations elsewhere in Britain, and, therefore, a review of the impact of the London Docklands' initiative is appropriate. In this paper I outline the impact of the urban development corporation, in terms of economic regeneration and of the effect on local unemployment. It is argued that demand-led economic regeneration, based on the redevelopment of derelict land, has changed the nature of the local economy, although as yet it has not had any significant effect on the numbers of jobs in the local economy, because of continued decline in existing industries and because of pressures on firms to relocate. Local unemployment has gone on increasing, and evidence is presented to show that labour-market adjustment mechanisms and recruitment patterns severely limit the impact of economic regeneration on unemployment in Docklands. Even major developments, such as the proposed office complex on Canary Wharf, will have only a relatively small effect on local unemployment. Local labour-market intervention has been slow to occur, limited in its aims, and uncoordinated. Urban development corporations are useful policy devices for the encouragement of large-scale land redevelopment, but in their present form they do not represent a complete solution to the economic and employment problems of depressed urban areas.

scholarly journals Critical Chain Design Structure Matrix Method for Construction Project Scheduling under Rework Scenarios

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Guofeng Ma ◽  
Keke Hao ◽  
Yu Xiao ◽  
Tiancheng Zhu
Keyword(s):  
Project Scheduling ◽  
Large Scale ◽  
Construction Project ◽  
Design Structure Matrix ◽  
Structure Matrix ◽  
Project Completion ◽  
Promising Tool ◽  
Design Structure ◽  
The Impact ◽  
Critical Chain

Rework risks have been a major challenge in the construction industry that constantly affects project schedules and threatens on-time project completion. Traditional project scheduling methods are not capable of modeling rework relationships between activities and mitigating the impact of resulting uncertainties during the development of project schedules. To address this challenge, a critical chain design structure matrix (CCDSM) method is proposed in this paper. The CCDSM method aims to develop construction project schedules that are adaptive to rework scenarios and robust against rework risks. The CCDSM method models and displays large-scale rework relationships among activities and introduces a new rework buffer to quantitatively represent the impact of rework instances in project schedules. A max-plus algorithm is adopted in CCDSM to transform complex logic relationships into simple matrix operations, reducing computational load of schedule generation. A case study was conducted to demonstrate the implementation of the CCDSM method and assess its effectiveness in addressing rework risks. The results showed that the CCDSM is a promising tool to generate schedules, which could improve on-time project completion rate and reduce impacts of varying rework scenarios on project execution.

scholarly journals The Promise of Sleep: A Multi-Sensor Approach for Accurate Sleep Stage Detection Using the Oura Ring

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4302
Author(s):  
Marco Altini ◽  
Hannu Kinnunen
Keyword(s):  
Machine Learning ◽  
Large Scale ◽  
Health Management ◽  
Sleep Stage ◽  
Nrem Sleep ◽  
Physiological Data ◽  
Promising Tool ◽  
Stage Classification ◽  
Sleep Stage Classification ◽  
The Impact

Consumer-grade sleep trackers represent a promising tool for large scale studies and health management. However, the potential and limitations of these devices remain less well quantified. Addressing this issue, we aim at providing a comprehensive analysis of the impact of accelerometer, autonomic nervous system (ANS)-mediated peripheral signals, and circadian features for sleep stage detection on a large dataset. Four hundred and forty nights from 106 individuals, for a total of 3444 h of combined polysomnography (PSG) and physiological data from a wearable ring, were acquired. Features were extracted to investigate the relative impact of different data streams on 2-stage (sleep and wake) and 4-stage classification accuracy (light NREM sleep, deep NREM sleep, REM sleep, and wake). Machine learning models were evaluated using a 5-fold cross-validation and a standardized framework for sleep stage classification assessment. Accuracy for 2-stage detection (sleep, wake) was 94% for a simple accelerometer-based model and 96% for a full model that included ANS-derived and circadian features. Accuracy for 4-stage detection was 57% for the accelerometer-based model and 79% when including ANS-derived and circadian features. Combining the compact form factor of a finger ring, multidimensional biometric sensory streams, and machine learning, high accuracy wake-sleep detection and sleep staging can be accomplished.

Impact of COVID-19 on Nuclear Medicine in Germany, Austria and Switzerland: An International Survey in April 2020

2020 ◽  
Vol 59 (04) ◽  
pp. 294-299 ◽  
Author(s):  
Lutz S. Freudenberg ◽  
Ulf Dittmer ◽  
Ken Herrmann
Keyword(s):  
Nuclear Medicine ◽  
Health Systems ◽  
Personal Protective Equipment ◽  
Large Scale ◽  
Diagnostic Procedures ◽  
Protective Equipment ◽  
Current Crisis ◽  
Web Based ◽  
Public Versus Private ◽  
The Impact

Abstract Introduction Preparations of health systems to accommodate large number of severely ill COVID-19 patients in March/April 2020 has a significant impact on nuclear medicine departments. Materials and Methods A web-based questionnaire was designed to differentiate the impact of the pandemic on inpatient and outpatient nuclear medicine operations and on public versus private health systems, respectively. Questions were addressing the following issues: impact on nuclear medicine diagnostics and therapy, use of recommendations, personal protective equipment, and organizational adaptations. The survey was available for 6 days and closed on April 20, 2020. Results 113 complete responses were recorded. Nearly all participants (97 %) report a decline of nuclear medicine diagnostic procedures. The mean reduction in the last three weeks for PET/CT, scintigraphies of bone, myocardium, lung thyroid, sentinel lymph-node are –14.4 %, –47.2 %, –47.5 %, –40.7 %, –58.4 %, and –25.2 % respectively. Furthermore, 76 % of the participants report a reduction in therapies especially for benign thyroid disease (-41.8 %) and radiosynoviorthesis (–53.8 %) while tumor therapies remained mainly stable. 48 % of the participants report a shortage of personal protective equipment. Conclusions Nuclear medicine services are notably reduced 3 weeks after the SARS-CoV-2 pandemic reached Germany, Austria and Switzerland on a large scale. We must be aware that the current crisis will also have a significant economic impact on the healthcare system. As the survey cannot adapt to daily dynamic changes in priorities, it serves as a first snapshot requiring follow-up studies and comparisons with other countries and regions.

HOME VISITS DURING THE FIRST MONTH OF DELIVERY FOR RECENTLY DELIVERED WOMEN IN UTTAR PRADESH, INDIA

2020 ◽  
Vol 6 (5) ◽  
pp. 1183-1189
Author(s):  
Dr. Tridibesh Tripathy ◽  
Dr. Umakant Prusty ◽  
Dr. Chintamani Nayak ◽  
Dr. Rakesh Dwivedi ◽  
Dr. Mohini Gautam
Keyword(s):  
Large Scale ◽  
National Level ◽  
Uttar Pradesh ◽  
Life Time ◽  
Structured Interview ◽  
The Other ◽  
Registration System ◽  
Action Group ◽  
Current Article ◽  
The Impact

The current article of Uttar Pradesh (UP) is about the ASHAs who are the daughters-in-law of a family that resides in the same community that they serve as the grassroots health worker since 2005 when the NRHM was introduced in the Empowered Action Group (EAG) states. UP is one such Empowered Action Group (EAG) state. The current study explores the actual responses of Recently Delivered Women (RDW) on their visits during the first month of their recent delivery. From the catchment area of each of the 250 ASHAs, two RDWs were selected who had a child in the age group of 3 to 6 months during the survey. The response profiles of the RDWs on the post- delivery first month visits are dwelled upon to evolve a picture representing the entire state of UP. The relevance of the study assumes significance as detailed data on the modalities of postnatal visits are available but not exclusively for the first month period of their recent delivery. The details of the post-delivery first month period related visits are not available even in large scale surveys like National Family Health Survey 4 done in 2015-16. The current study gives an insight in to these visits with a five-point approach i.e. type of personnel doing the visit, frequency of the visits, visits done in a particular week from among those four weeks separately for the three visits separately. The current study is basically regarding the summary of this Penta approach for the post- delivery one-month period.     The first month period after each delivery deals with 70% of the time of the postnatal period & the entire neonatal period. Therefore, it does impact the Maternal Mortality Rate & Ratio (MMR) & the Neonatal Mortality Rates (NMR) in India and especially in UP through the unsafe Maternal & Neonatal practices in the first month period after delivery. The current MM Rate of UP is 20.1 & MM Ratio is 216 whereas the MM ratio is 122 in India (SRS, 2019). The Sample Registration System (SRS) report also mentions that the Life Time Risk (LTR) of a woman in pregnancy is 0.7% which is the highest in the nation (SRS, 2019). This means it is very risky to give birth in UP in comparison to other regions in the country (SRS, 2019). This risk is at the peak in the first month period after each delivery. Similarly, the current NMR in India is 23 per 1000 livebirths (UNIGME,2018). As NMR data is not available separately for states, the national level data also hold good for the states and that’s how for the state of UP as well. These mortalities are the impact indicators and such indicators can be reduced through long drawn processes that includes effective and timely visits to RDWs especially in the first month period after delivery. This would help in making their post-natal & neonatal stage safe. This is the area of post-delivery first month visit profile detailing that the current article helps in popping out in relation to the recent delivery of the respondents.   A total of four districts of Uttar Pradesh were selected purposively for the study and the data collection was conducted in the villages of the respective districts with the help of a pre-tested structured interview schedule with both close-ended and open-ended questions.  The current article deals with five close ended questions with options, two for the type of personnel & frequency while the other three are for each of the three visits in the first month after the recent delivery of respondents. In addition, in-depth interviews were also conducted amongst the RDWs and a total 500 respondents had participated in the study.   Among the districts related to this article, the results showed that ASHA was the type of personnel who did the majority of visits in all the four districts. On the other hand, 25-40% of RDWs in all the 4 districts replied that they did not receive any visit within the first month of their recent delivery. Regarding frequency, most of the RDWs in all the 4 districts received 1-2 times visits by ASHAs.   Regarding the first visit, it was found that the ASHAs of Barabanki and Gonda visited less percentage of RDWs in the first week after delivery. Similarly, the second visit revealed that about 1.2% RDWs in Banda district could not recall about the visit. Further on the second visit, the RDWs responded that most of them in 3 districts except Gonda district did receive the second postnatal visit in 7-15 days after their recent delivery. Less than half of RDWs in Barabanki district & just more than half of RDWs in Gonda district received the third visit in 15-21 days period after delivery. For the same period, the majority of RDWs in the rest two districts responded that they had been entertained through a home visit.

The Impact of Quantitative Easing on Emerging Markets – Literature Review

e-Finanse ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 67-76
Author(s):  
Piotr Bartkiewicz
Keyword(s):  
Emerging Markets ◽  
Large Scale ◽  
Empirical Literature ◽  
Quantitative Easing ◽  
Methodological Choices ◽  
The Subject ◽  
Methodological Approaches ◽  
The Impact ◽  
Sufficient Precision

AbstractThe article presents the results of the review of the empirical literature regarding the impact of quantitative easing (QE) on emerging markets (EMs). The subject is of interest to policymakers and researchers due to the increasingly larger role of EMs in the world economy and the large-scale capital flows occurring after 2009. The review is conducted in a systematic manner and takes into consideration different methodological choices, samples and measurement issues. The paper puts the summarized results in the context of transmission channels identified in the literature. There are few distinct methodological approaches present in the literature. While there is a consensus regarding the direction of the impact of QE on EMs, its size and durability have not yet been assessed with sufficient precision. In addition, there are clear gaps in the empirical findings, not least related to relative underrepresentation of the CEE region (in particular, Poland).

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