Flow modelling to quantify structural control on CO2 migration and containment, CCS South West Hub, Australia

2021 ◽  
Vol 27 (2) ◽  
pp. petgeo2020-094
Author(s):  
Laurent Langhi ◽  
Julian Strand ◽  
Ludovic Ricard
Keyword(s):  
Structural Control ◽  
Co2 Storage ◽  
Low Flow ◽  
Hydrodynamic Models ◽  
Worst Case ◽  
Content Type ◽  
South West ◽  
Fault Properties ◽  
Main Compartment ◽  
Injection Depth

In order to reduce uncertainties around CO2 containment for the South West Hub CCS site (Western Australia), conceptual fault hydrodynamic models were defined and numerical simulations were carried out. These simulations model worst-case scenarios with a plume reaching a main compartment-bounding fault near the proposed injection depth and at the faulted interface between the primary and secondary containment interval.The conceptual models incorporate host-rock and fault properties accounting for fault-zone lithology, cementation and cataclastic processes but with no account made for geomechanical processes as the risk of reactivation is perceived as low. Flow simulations were performed to assess cross-fault and upfault migration in the case of plume–faults interaction.Results near the injection depth suggest that the main faults are likely to experience a significant reduction in transmissivity and impede CO2 flow. This could promote the migration of CO2 vertically or along the stratigraphic dip.Results near the interface between the primary and secondary containment intervals show that none of the main faults would critically control CO2 flow nor would they act as primary leakage pathways. CO2 flow is predicted to be primarily controlled by the sedimentological morphology. The presence of baffles in the secondary containment interval is expected to be associated with local CO2 accumulations; additional permeability impacts introduced by faults are minor.Thematic collection: This article is part of the Geoscience for CO2 storage collection available at: https://www.lyellcollection.org/cc/geoscience-for-co2-storage

Road to default: Tracoma holding Berhad Bai Bithaman Ajil Debt securities (BaIDS)

2015 ◽  
Vol 5 (5) ◽  
pp. 1-6
Author(s):  
A.M. Hafizi ◽  
Shahida Shahimi ◽  
Mohd Hafizuddin Syah Bangaan Abdullah ◽  
M. Badrul Hakimi Daud
Keyword(s):  
Learning Outcomes ◽  
Capital Market ◽  
Credit Rating ◽  
Subject Area ◽  
Capital Requirements ◽  
Fund Raising ◽  
Case Scenario ◽  
Worst Case ◽  
Content Type ◽  
Analytical Skills

Subject area Islamic Finance and Investment Study level/applicability Level of program/audience: Advanced undergraduate and postgraduate. Courses Intermediate and Advanced Finance, Economics, Islamic Economics & Finance, Islamic Banking & Finance, Islamic Capital Market and other relevant courses. Specifictopics/syllabus Capital markets instruments, conventional or Islamic. Case overview This case focuses on Tracoma Holding Berhad Bai Bithaman Ajil Debt Securities (BaIDS) amounting to RM 100 million which was issued by Tracoma Holding Berhad in 2005. It was the first issuance of a sukuk (Islamic debt securities or bond) by the company. The proceeds were used to finance its growth and to repay existing bank borrowings and capital requirements. This case is interesting, as it allows students to study the bai bithaman ajil sukuk structure and issuance process in the Malaysian capital market. It also provides basic financial transaction and credit rating of sukuk which requires analytical skills. Being a debt-based facility, the sukuk was subjected to credit rating evaluation by the MARC, the rating agency appointed by the company. Further downgrading of the sukuk meant it would lead to the worst-case scenario. Some actions needed to be taken to solve this issue; therefore, the CFO suggested an urgent meeting with the sukuk holders. Expected learning outcomes The students should be able to: understand the issuance process and the principle of BBA (bai bithamin ajil) in sukuk structure; understand reason(s) methods of fund raising by firm and the allocations of fund; understand the sukuk default issue; analyze the reasons for sukuk default; understand the importance of debt securities credit ratings; and identify investors' protection in the case of sukuk default. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or email [email protected] to request teaching notes.

Cerebral microdialysis monitoring: determination of normal and ischemic cerebral metabolisms in patients with aneurysmal subarachnoid hemorrhage

2000 ◽  
Vol 93 (5) ◽  
pp. 808-814 ◽  
Author(s):  
Mette K. Schulz ◽  
Lars Peter Wang ◽  
Mogens Tange ◽  
Per Bjerre
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Cerebral Ischemia ◽  
Delayed Cerebral Ischemia ◽  
Neuronal Injury ◽  
Low Flow ◽  
Cerebral Microdialysis ◽  
Intracerebral Microdialysis ◽  
Content Type ◽  
Wide Range ◽  
Fine Print

Object. The success of treatment for delayed cerebral ischemia is time dependent, and neuronal monitoring methods that can detect early subclinical levels of cerebral ischemia may improve overall treatment results. Cerebral microdialysis may represent such a method. The authors' goal was to characterize patterns of markers of energy metabolism (glucose, pyruvate, and lactate) and neuronal injury (glutamate and glycerol) in patients with subarachnoid hemorrhage (SAH), in whom ischemia was or was not suspected.Methods. By using low-flow intracerebral microdialysis monitoring, central nervous system extracellular fluid concentrations of glucose, pyruvate, lactate, glutamate, and glycerol were determined in 46 patients suffering from poor-grade SAH. The results in two subgroups were analyzed: those patients with no clinical or radiological signs of cerebral ischemia (14 patients) and those who succumbed to brain death (five patients).Significantly lower levels of energy substrates and significantly higher levels of lactate and neuronal injury markers were observed in patients with severe and complete ischemia when compared with patients without symptoms of ischemia (glucose 0 compared with 2.12 ± 0.15 mmol/L; pyruvate 0 compared with 151 ± 11.5 µmol; lactate 6.57 ± 1.07 compared with 3.06 ± 0.32 mmol/L; glycerol 639 ± 91 compared with 81.6 ± 12.4 µmol; and glutamate 339 ± 53.4 compared with 14 ± 3.33 µmol). Immediately after catheter placement, glutamate concentrations declined over the first 4 to 6 hours to reach stable values. The remaining parameters exhibited stable values after 1 to 2 hours.Conclusions. The results confirm that intracerebral microdialysis monitoring of patients with SAH can be used to detect patterns of cerebral ischemia. The wide range from normal to severe ischemic values calls for additional studies to characterize further incomplete and possible subclinical levels of ischemia.

Sprawl of the COVID-19 in changing scenario: a methodology based on social interaction

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Gaurav Kumar ◽  
Akshay Kumar ◽  
Farhan Mohammad Khan ◽  
Rajiv Gupta
Keyword(s):  
Social Interaction ◽  
Design Methodology ◽  
Mitigation Strategy ◽  
Recent Past ◽  
Scenario Development ◽  
Worst Case ◽  
Content Type ◽  
Management Scheme ◽  
Business As Usual ◽  
Inter State

PurposeThere are several methods developed in the recent past to predict the spread of COVID-19 in different countries. However, due to changing scenarios in terms of interaction among people, none could predict the case close to the actual figures. An attempt to simulate people's interaction due to economic reopening concerning the confirmed cases at various places as per changing situation has been made. The scenario development method's base lies in the hypothesis that if there were no inter-state transportation during India's lockdown after May 24th, the number of infection cases would have started lowering down in a normalized progression.Design/methodology/approachThis study has developed three scenarios from the worst to the business-as-usual to the best in order to project the COVID-19 infections in India concerning infections observed from January 30th till May 24th, 2020, since the domestic flights became operational from May 25th, 2020, in India.FindingsBased on the observed cases till May 24th, the rise of cases is projected further in a random progression and superimposed to the normal progression. The results obtained in the three scenarios present that worst case needs complete lockdown, business-as-usual case needs regulatory lockdown and best case assures complete lockdown release by the second week of September 2020. This study suggests the preparedness and mitigation strategy for a threefold lockdown management scheme in all-inclusive.Originality/valueThe work has been done on a hypothesis which is solely original.

scholarly journals Lysinibacillus antri sp. nov., isolated from cave soil

2020 ◽  
Vol 70 (5) ◽  
pp. 3295-3299 ◽  
Author(s):  
Manik Prabhu Narsing Rao ◽  
Zhou-Yan Dong ◽  
Xue-Ke Niu ◽  
Kun Zhang ◽  
Ying-Qian Kang ◽  
...  
Keyword(s):  
Cell Wall ◽  
Novel Species ◽  
Guizhou Province ◽  
Species Delineation ◽  
Gram Stain ◽  
West China ◽  
Content Type ◽  
South West ◽  
Optimum Ph ◽  
Genome Comparisons

A Gram-stain-positive, motile, rod-shaped and endospore-forming strain, SYSU K30002T, was isolated from a soil sample collected from a karst cave in Xingyi county, Guizhou province, south-west China. SYSU K30002T grew at 28–40 °C (optimum, 37 °C), at pH 5.0–8.0 (optimum, pH 7.0) and in the presence of 0–4 % (w/v) NaCl (optimum in the absence of NaCl). The cell-wall peptidoglycan type was A4α (Lys–Asp). The cell-wall sugars of SYSU K30002T were ribose, galactose and mannose, and MK-7 was the menaquinone. The major fatty acids were iso-C15 : 0, C16 : 1 ω7c alcohol and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids. The G+C content of the genomic DNA was 36.1 mol%. The average nucleotide identity values between SYSU K30002T and its closest relatives were below the cut-off level (95–96 %) for species delineation. Based on phenotypic, chemotaxonomic and genome comparisons, strain SYSU K30002T represents a novel species of the genus Lysinibacillus , for which the name Lysinibacillusantri sp. nov. is proposed. The type strain is SYSU K30002T (=KCTC 33955T=CGMCC 1.13504T).

scholarly journals Decision making under interval uncertainty: toward (somewhat) more convincing justifications for Hurwicz optimism-pessimism approach

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Warattaya Chinnakum ◽  
Laura Berrout Ramos ◽  
Olugbenga Iyiola ◽  
Vladik Kreinovich
Keyword(s):  
Decision Making ◽  
Real Life ◽  
Interval Uncertainty ◽  
Lower And Upper Bounds ◽  
Worst Case ◽  
Content Type ◽  
Expected Gain ◽  
Utility Approach ◽  
Interval Valued ◽  
Weighted Combination

Purpose In real life, we only know the consequences of each possible action with some uncertainty. A typical example is interval uncertainty, when we only know the lower and upper bounds on the expected gain. A usual way to compare such interval-valued alternatives is to use the optimism–pessimism criterion developed by Nobelist Leo Hurwicz. In this approach, a weighted combination of the worst-case and the best-case gains is maximized. There exist several justifications for this criterion; however, some of the assumptions behind these justifications are not 100% convincing. The purpose of this paper is to find a more convincing explanation. Design/methodology/approach The authors used utility approach to decision-making. Findings The authors proposed new, hopefully more convincing, justifications for Hurwicz’s approach. Originality/value This is a new, more intuitive explanation of Hurwicz’s approach to decision-making under interval uncertainty.

Unruptured intracranial aneurysms and arteriovenous malformations: frequency of intracranial hemorrhage and relationship of lesions

1990 ◽  
Vol 73 (6) ◽  
pp. 859-863 ◽  
Author(s):  
Robert D. Brown ◽  
David O. Wiebers ◽  
Glenn S. Forbes
Keyword(s):  
Intracranial Hemorrhage ◽  
Arteriovenous Malformations ◽  
Low Flow ◽  
Content Type ◽  
Unruptured Intracranial Aneurysms ◽  
The Difference ◽  
Arterial Feeder ◽  
Relationship Of ◽  
The Relationship ◽  
Feeding Systems

✓ Among 91 patients with unruptured intracranial arteriovenous malformations (AVM's), 16 patients had 26 unruptured intracranial saccular aneurysms. An actuarial analysis showed the risk of intracranial hemorrhage among patients with coexisting aneurysm and AVM to be 7% per year at 5 years following diagnosis compared to 1.7% for patients with AVM alone. The difference in length of survival free of hemorrhage was significant (log-rank, p < 0.0007). Several angiographic and clinical parameters were investigated to better understand the relationship of these lesions. The aneurysms occurred in similar percentages in patients with small, medium, and large AVM's. Twenty-five aneurysms were on arteries feeding the malformation system, almost equally distributed proximally and distally. Eleven aneurysms were atypical in location, and all arose from primary or secondary branch feeders to the malformation; 24 were on enlarged feeding arteries. Eleven (16%) of the 67 patients with high-flow AVM's had associated aneurysms, compared with five (21%) of the 24 patients with low-flow AVM's. Four (16%) of 25 low-shunt malformations and 12 (18%) of 65 high-shunt malformations had associated aneurysms. All five aneurysms associated with low-shunt malformations were on a direct arterial feeder of the malformation. These data suggest that the intracranial AVM's predispose to aneurysm formation within AVM feeding systems and that the mechanism is not simply based upon the high blood flow or high arteriovenous shunt in these systems.

Evaluation of supply chain resilience index: a graph theory based approach

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nishtha Agarwal ◽  
Nitin Seth ◽  
Ashish Agarwal
Keyword(s):  
Supply Chain ◽  
Adjacency Matrix ◽  
Theoretic Approach ◽  
Worst Case ◽  
Content Type ◽  
Supply Chain Resilience ◽  
Graph Theoretic ◽  
Graph Theoretic Approach ◽  
Resilience Index ◽  
Index Value

PurposeThe present study aims at developing a model to quantify supply chain resilience as a single numerical value. The numerical value is called resilience index that measures the resilience capability of the case company's supply chain. The model calculates the index value based on the interactions between the enablers of supply chain resilience and its dimensions.Design/methodology/approachGraph theoretic approach (GTA) is used to evaluate the resilience index for the case company's supply chain. In GTA, the dimensions of resilience enablers and their interdependencies are modelled through a digraph. The digraph depicting the influence of each dimension is converted into an adjacency matrix. The permanent function value of the adjacency matrix is called the resilience index (RI).FindingsThe proposed approach has been illustrated in context of an Indian automobile organization, and value of the RI is evaluated. The best case and the worst-case values are also obtained with the help of GTA. It is noted from the model that strategic level dimension of enablers is most important in contributing towards supply chain resilience. They are followed by tactical and operational level enablers. The GTA framework proposed will help supply chain practitioners to evaluate and benchmark the supply chain resilience of their respective organizations with the best in the industry.Originality/valueA firm can compare the RI of its own supply chain with other's supply chain or with the best in the industry for benchmarking purpose. Benchmarking of resilience will help organizations in developing strategies to compete in dynamic market scenario.

scholarly journals Worst-case analysis of electronic circuits based on an analytic forward solver approach

2019 ◽  
Vol 38 (5) ◽  
pp. 1655-1666
Author(s):  
Mario Schenk ◽  
Annette Muetze ◽  
Klaus Krischan ◽  
Christian Magele
Keyword(s):  
Linear Models ◽  
Piecewise Linear ◽  
Quadratic Program ◽  
Worst Case Analysis ◽  
State Equations ◽  
Case Scenario ◽  
Worst Case ◽  
Sqp Method ◽  
Content Type ◽  
Worst Case Scenario

Purpose The purpose of this paper is to evaluate the worst-case behavior of a given electronic circuit by varying the values of the components in a meaningful way in order not to exceed pre-defined currents or voltages limits during a transient operation. Design/methodology/approach An analytic formulation is used to identify the time-dependent solution of voltages or currents using proper state equations in closed form. Circuits with linear elements can be described by a system of differential equations, while circuits composing nonlinear elements are described by piecewise-linear models. A sequential quadratic program (SQP) is used to find the worst-case scenario. Findings It is found that the worst-case scenario can be obtained with as few solutions to the forward problem as possible by applying an SQP method. Originality/value The SQP method in combination with the analytic forward solver approach shows that the worst-case limit converges in a few steps even if the worst-case limit is not on the boundary of the parameters.

Ferries as travelling landscapes: tourism and watery mobilities

2020 ◽  
Vol 14 (3) ◽  
pp. 321-334
Author(s):  
Eva McGrath ◽  
Nichola Harmer ◽  
Richard Yarwood
Keyword(s):  
Design Methodology ◽  
Participant Observation ◽  
Material Structure ◽  
Place Making ◽  
Content Type ◽  
Mixed Methods Approach ◽  
South West ◽  
Original Contribution ◽  
Mode Of Transport ◽  
South West England

Purpose The purpose of this paper is to highlight the use of small river ferries as an under-researched but novel mode of travel which enhances and brings new dimensions to tourist experiences of travelling landscapes. Design/methodology/approach The study used a mixed methods approach including participant observation, a survey and interviews with ferry users and staff at one river crossing in South West England. Findings The ferry attracts tourists as a different and practical mode of transport. The river crossing provides an experience of being on water, and the material structure of the ferry significantly shapes on-board interactions whilst providing new perspectives of place. Research limitations/implications This article draws on data collected for a study of ferry crossings conducted at three sites in Devon and Cornwall, England, using multiple methods. The material presented in this article focuses on one site and draws on four interviews, twelve reflection cards and observations. Social implications The research highlighted the extent to which the ferry is dependent on tourist use. At the same time, it reveals the extent to which the crossing enriches the tourist experience and celebrates a ferry’s contribution to local place-making. Originality/value The majority of research on ferry crossings focuses on commuter experiences, marine crossings and larger passenger vessels. This article makes an original contribution to literature on ferries, as it offers a perspective on tourist experiences of river ferry crossings, reveals how the ferry structure influences interrelations on-board and provides distinctive insights into place through a focus on movement across water.

scholarly journals Exploring the role of volunteers in social care for older adults

2020 ◽  
Vol 21 (2) ◽  
pp. 129-139 ◽  
Author(s):  
Ailsa Cameron ◽  
Eleanor K. Johnson ◽  
Paul B. Willis ◽  
Liz Lloyd ◽  
Randall Smith
Keyword(s):  
Older Adults ◽  
Older People ◽  
Social Care ◽  
Evidence Base ◽  
Care Staff ◽  
Small Scale ◽  
The South ◽  
Content Type ◽  
South West

Purpose This paper aims to report the findings of a study that explores the contribution volunteers make to social care for older adults, identifying lessons for the social care sector and policymakers. Design/methodology/approach An exploratory multiple case study design was used to capture the perspectives and experiences of managers of services, volunteer co-ordinators, volunteers, paid care staff and older people. Seven diverse social care organisations took part in the study drawn from three locations in the South West of England. Findings This study identified three distinct models of volunteer contribution to social care services for older people. Although the contributions made by volunteers to services are valued, the study drew attention to some of the challenges related to their involvement. Research limitations/implications The organisations taking part in this small-scale study were all based in the South West of England, and the findings are therefore not generalisable but contribute to the growing evidence base related to this important field. Practical implications This study demonstrates the importance of the volunteer co-ordinator role and suggests that it is properly funded and resourced. It also confirms the importance of volunteers receiving appropriate training and support. Originality/value Given the increasing involvement of volunteers in the provision of social care, this paper provides lessons to ensure the role of volunteers in social care enhances rather than diminishes the quality of care provided.

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