Early termination strategies with asynchronous parallel optimization in application to automatic calibration of groundwater PDE models

A Stabilizing Control Algorithm for Asynchronous Parallel Quadratic Programing via Dual Decomposition

ASME Letters in Dynamic Systems and Control ◽

10.1115/1.4046365 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Kooktae Lee

Keyword(s):

Control Algorithm ◽

Iteration Step ◽

Parallel Optimization ◽

Optimal Solutions ◽

Dual Decomposition ◽

Worst Case ◽

Stabilizing Control ◽

Dual Variables ◽

The Stability ◽

Asynchronous Parallel

Abstract This paper proposes a control algorithm for stable implementation of asynchronous parallel quadratic programing (PQP) through a dual decomposition technique. In general, distributed and parallel optimization requires synchronization of data at each iteration step due to the interdependency of data. The synchronization latency may incur a large amount of waiting time caused by an idle process during computation. We aim to mitigate this synchronization penalty in PQP problems by implementing asynchronous updates of the dual variable. The price to pay for adopting asynchronous computing algorithms is the unpredictability of the solution, resulting in a tradeoff between speedup and accuracy. In the worst case, the state of interest may become unstable owing to the stochastic behavior of asynchrony. The stability condition of asynchronous PQP problems is investigated by employing the switched system framework. A formal algorithm is provided to ensure the asymptotic stability of dual variables. Furthermore, it is shown that the implementation of the proposed algorithm guarantees the uniqueness of optimal solutions, irrespective of asynchronous behavior. To verify the validity of the proposed methods, simulation results are presented.

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Modernizing the lending facility under concession agreements

Finance and Credit ◽

10.24891/fc.26.7.1590 ◽

2020 ◽

Vol 26 (7) ◽

pp. 1590-1609

Author(s):

V.A. Rakhaev

Keyword(s):

Financial Structure ◽

Bank Lending ◽

Early Termination ◽

Scientific Methods ◽

Financial Condition ◽

Revenue Collection ◽

Analysis And Synthesis ◽

Financing Mechanism ◽

General Scientific ◽

The Russian Federation

Subject. The article addresses modernization of lending facilities under concession agreements. It is important for evaluating the terms of credit transactions, effectiveness of credit projects, and the concessionaire's ability to repay the loan. Objectives. The purpose is to review the current financing mechanism and underpin approaches to improving the credit facilities within concession agreements. Methods. The study rests on general scientific methods, like the systems and logical analysis and synthesis, principles of induction and deduction, financial calculation techniques. The analytical part employs the balance method, methods of financial coefficients and the method of technical and economic estimates. Results. I analyzed the financial structure and special characteristics of concession agreements, parameters of concessionaires’ activities; considered the types of risks inherent in bank lending under concession agreements, methods for their identification and mitigation; offered a mechanism of lending, including the structure of credit transactions, restrictions for the financial condition of concessionaires, additional requirements and penalties for their non-fulfillment. The findings can help banks define lending parameters for concession agreements. The provided recommendations may be useful for consideration by the authorities of the constituent entities of the Russian Federation. Conclusions. It is possible to reduce the risks of lending under concession contracts, if their terms and conditions are stable, and if the lost income of concessionaires is compensated in the event of early termination. Reasonable tariffs for works and services and increased revenue collection will promote this type of lending.

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Faculty Opinions recommendation of Bimodal expression of PHO84 is modulated by early termination of antisense transcription.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718048930.793481173 ◽

2013 ◽

Author(s):

Daniel Reines

Keyword(s):

Antisense Transcription ◽

Early Termination

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Da Importância do Vencimento Antecipado do Derivativo para Constituir Provisão: Caso Oi S.A. (Relevance of Derivatives Early Termination to Create Accounting Provision: Oi S.A. Case)

SSRN Electronic Journal ◽

10.2139/ssrn.3442217 ◽

2019 ◽

Author(s):

Ricardo Genis Mourão

Keyword(s):

Early Termination

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Network analysis models – the secret for success

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0129 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 383-388

Author(s):

D.M. Rogers

Keyword(s):

Mathematical Model ◽

Field Data ◽

Essential Element ◽

Distribution Networks ◽

Automatic Calibration ◽

Supply And Distribution ◽

The World ◽

Optimum Approach ◽

Analysis Models

Water is a fundamental necessity of life. Yet water supply and distribution networks the world over are old and lacking in adequate maintenance. Consequently they often leak as much water as they deliver and provide an unacceptable quality of service to the customer. In certain parts of the world, water is available only for a few hours of the day. The solution is to build a mathematical model to simulate the operation of the real network in all of its key elements and apply it to optimise its operation. To be of value, the results of the model must be compared with field data. This process is known as calibration and is an essential element in the construction of an accurate model. This paper outlines the optimum approach to building and calibrating a mathematical model and how it can be applied to automatic calibration systems.

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Predictivity/Translatability of Toxicities Observed in Nonclinical Toxicology Studies to Clinical Safety Outcomes in Drug Development: Case Examples

International Journal of Toxicology ◽

10.1177/1091581819894281 ◽

2019 ◽

Vol 39 (2) ◽

pp. 141-150

Author(s):

Nicola J. Stagg ◽

Hanan N. Ghantous ◽

Robert Roth ◽

Kenneth L. Hastings

Keyword(s):

Drug Development ◽

Annual Meeting ◽

Clinical Studies ◽

Early Termination ◽

New Drugs ◽

Clinical Safety ◽

Case Examples ◽

Palm Springs ◽

Starting Dose ◽

Good Concordance

Nonclinical toxicology studies are conducted to characterize the potential toxicities and establish a safe starting dose for new drugs in clinical studies, but the question remains as to how predictable/translatable the nonclinical safety findings are to humans. In many cases, there is good concordance between nonclinical species and patients. However, there are cases for which there is a lack of predictivity or translatability that led to early termination of clinical studies due to unanticipated toxicities or early termination of programs before making it to the clinic due to unacceptable nonclinical toxicities assumed to be translatable. A few case examples of safety findings that are translatable versus safety findings that are not translatable and why they are not translateable were presented as a symposium at the 38th Annual Meeting of the American College of Toxicology in Palm Springs, California, and are discussed in this article.

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Appropriate Number of Treatment Sessions in Virtual Reality-Based Individual Cognitive Behavioral Therapy for Social Anxiety Disorder

Journal of Clinical Medicine ◽

10.3390/jcm10050915 ◽

2021 ◽

Vol 10 (5) ◽

pp. 915

Author(s):

Hyu Seok Jeong ◽

Jee Hyun Lee ◽

Hesun Erin Kim ◽

Jae-Jin Kim

Keyword(s):

Virtual Reality ◽

Anxiety Disorder ◽

Social Anxiety ◽

Cognitive Behavioral Therapy ◽

Social Anxiety Disorder ◽

Behavioral Therapy ◽

Early Termination ◽

Cognitive Behavioral ◽

Significant Group ◽

Extension Group

Virtual reality (VR) was introduced to maximize the effect of cognitive behavioral therapy (CBT) by efficiently performing exposure therapy. The purpose of this study was to find out whether VR-based individual CBT with relatively few treatment sessions is effective in improving social anxiety disorder (SAD). This therapy was applied to 115 patients with SAD who were retrospectively classified into 43 patients who completed the nine or 10 sessions normally (normal termination group), 52 patients who finished the sessions early (early termination group), and 20 patients who had extended the sessions (session extension group). The Brief Fear of Negative Evaluation Scale (BFNE) scores tended to decrease in all groups as the session progressed, and the slope of decrease was the steepest in the early termination group and the least steep in the session extension group. Severity of social anxiety in the last session and symptom reduction rate showed no significant group difference. Our findings suggest that short-term VR-based individual CBT of nine to 10 sessions may be effective. When the therapeutic effect is insufficient during this period, the additional benefit may be minimal if the session is simply extended. The improvement in the early termination group suggests that even shorter sessions of five or six can also be effective.

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