A Study on Parameter Determination Method of Large-Scale and Complex Dynamic Systems With Judgment Functions (No. 2)—Applications

1983 ◽  
Vol 105 (2) ◽  
pp. 70-76
Author(s):  
Osamu Furukawa ◽  
Hiroyuki Hiroyasu ◽  
Satoshi Iida
Keyword(s):  
Large Scale ◽  
Jump Condition ◽  
Approximate Model ◽  
Parameter Determination ◽  
Complex Dynamic ◽  
Complex Dynamic Systems ◽  
System Equations ◽  
Quality Design ◽  
Statistical Identification ◽  
Selection Of

This paper deals with the parameter satisfaction problems of gas exchanging system, which are important from a standpoint of quality design. These problems have been difficult to solve, because their mathematical models are described by large-scale and complex dynamic system equations with many judgment functions. The report No. I [1] has already proposed the method to solve the parameter satisfaction problems of such systems. This method is one which sequentially exchanges the original mathematical model to the analyzable approximate model by means of selection of attributes with analysis-charts and statistical identification method with jump condition extended and which improves parameters simultaneously. In this paper, this method is applied to the above problems and a parameter improvement system which can improve many parameters efficiently without enormous calculations of partial derivatives is constructed. By the numerical calculations, satisfactory parameters could be obtained and it is shown that this method can give the solutions of the above problems. Moreover, its effectiveness for the fundamental and unsettled problems of such large-scale and complex systems in the field of mechanical engineering is demonstrated.

A Study on Parameter Determination Method of Large-Scale and Complex Dynamic Systems With Judgment Functions (No. 1)—Theory

1983 ◽  
Vol 105 (2) ◽  
pp. 64-69
Author(s):  
Osamu Furukawa ◽  
Hideomi Ikeshoji ◽  
Satoshi Iida
Keyword(s):  
Dynamic Systems ◽  
Large Scale ◽  
Optimization Methods ◽  
Approximate Model ◽  
Difficult Problem ◽  
Parameter Determination ◽  
Design Parameters ◽  
Dynamic Relationships ◽  
Complex Mechanical Systems ◽  
Selection Of

In the design of large-scale and complex mechanical systems, determination of design parameters is a very difficult problem. This study deals with parameter satisfaction problems of large-scale, complex, and dynamic systems with judgment functions. In order to solve these problems, a new method is proposed which sequentially exchanges the original mathematical model to an analyzable approximate model by means of the identification method and which improves a lot of parameters simultaneously. First, criteria of selection of attributes to build up approximate model are clarified. Moreover, as tools for selection of attributes, two analysis charts are proposed which express dynamic relationships among the attributes. Second, a general condition to determine the structure of approximate models and a statistical method to linearize the original model with judgment functions are derived. Finally, a combinatorial method of statistical identification and parameter optimization methods are proposed. By this method, some shortcomings of sensitivity analysis, decomposition technique (enormous calculations of partial derivatives) and statistical methods such as Monte Carlo method (bad convergency of solutions) can be avoided. As a result of this, it becomes possible to search satisfactory parameters efficiently.

scholarly journals Working memory and second language development: A complex, dynamic future?

2020 ◽  
Vol 10 (1) ◽  
pp. 89-109
Author(s):  
Daniel O. Jackson
Keyword(s):  
Working Memory ◽  
Second Language ◽  
Dynamic Systems Theory ◽  
Complex Dynamic ◽  
Dynamic Nature ◽  
Complex Dynamic Systems ◽  
Second Language Development ◽  
Reciprocal Influences ◽  
Selection Of

Working memory (WM) is inherently dynamic and complex, being a multi-faceted system that links storage and processing components; yet it is widely understood as internal. Hence, in second language (L2) research, its connection to complex dynamic systems theory (CDST) remains underspecified. This paper seeks to bridge a gap between CDST and WM in L2 research. First, definitions of WM are reviewed, along with evidence for its relationship to L2 outcomes. Next, a brief overview of CDST highlights its metatheoretical and methodological implications. Three perspectives are presented to illustrate how WM can be viewed in terms of major tenets in CDST. These consider WM effects as: (1) context-dependent, (2) interrelated with those of other variables, and (3) amenable to change across the lifespan. Despite this reappraisal, numerous challenges remain. Thus, in addition to noting research opportunities, the paper also considers measurement issues, such as the determination of boundaries and selection of appropriate timescales. In closing, while WM studies have shown its influence on L2 proficiency and processing, to more fully understand its dynamic nature, what is needed is further research on the reciprocal influences of bilingual development and changes in WM components, such as control of attention.

Platelet Anti-Aggregating Activity and Tolerance of Clopidogrel in Atherosclerotic Patients

1996 ◽  
Vol 76 (06) ◽  
pp. 0939-0943 ◽  
Author(s):  
B Boneu ◽  
G Destelle ◽  
Keyword(s):  
Platelet Aggregation ◽  
Large Scale ◽  
Bleeding Time ◽  
Antithrombotic Activity ◽  
Ambulatory Patients ◽  
Patients At Risk ◽  
Set Up ◽  
Ischemic Events ◽  
Large Scale Clinical Trial ◽  
Selection Of

SummaryThe anti-aggregating activity of five rising doses of clopidogrel has been compared to that of ticlopidine in atherosclerotic patients. The aim of this study was to determine the dose of clopidogrel which should be tested in a large scale clinical trial of secondary prevention of ischemic events in patients suffering from vascular manifestations of atherosclerosis [CAPRIE (Clopidogrel vs Aspirin in Patients at Risk of Ischemic Events) trial]. A multicenter study involving 9 haematological laboratories and 29 clinical centers was set up. One hundred and fifty ambulatory patients were randomized into one of the seven following groups: clopidogrel at doses of 10, 25, 50,75 or 100 mg OD, ticlopidine 250 mg BID or placebo. ADP and collagen-induced platelet aggregation tests were performed before starting treatment and after 7 and 28 days. Bleeding time was performed on days 0 and 28. Patients were seen on days 0, 7 and 28 to check the clinical and biological tolerability of the treatment. Clopidogrel exerted a dose-related inhibition of ADP-induced platelet aggregation and bleeding time prolongation. In the presence of ADP (5 \lM) this inhibition ranged between 29% and 44% in comparison to pretreatment values. The bleeding times were prolonged by 1.5 to 1.7 times. These effects were non significantly different from those produced by ticlopidine. The clinical tolerability was good or fair in 97.5% of the patients. No haematological adverse events were recorded. These results allowed the selection of 75 mg once a day to evaluate and compare the antithrombotic activity of clopidogrel to that of aspirin in the CAPRIE trial.

scholarly journals Methodology for Determining the Location of River Ports on a Modernized Waterway Based on Non-Cost Criteria: A Case Study of the Odra River Waterway

2021 ◽  
Vol 13 (6) ◽  
pp. 3571
Author(s):  
Bogusz Wiśnicki ◽  
Dorota Dybkowska-Stefek ◽  
Justyna Relisko-Rybak ◽  
Łukasz Kolanda
Keyword(s):  
Large Scale ◽  
Multicriteria Decision Making ◽  
Research Process ◽  
Optimal Selection ◽  
Investment Projects ◽  
Odra River ◽  
Research Problems ◽  
Selection Of ◽  
Construction Works

The paper responds to research problems related to the implementation of large-scale investment projects in waterways in Europe. As part of design and construction works, it is necessary to indicate river ports that play a major role within the European transport network as intermodal nodes. This entails a number of challenges, the cardinal one being the optimal selection of port locations, taking into account the new transport, economic, and geopolitical situation that will be brought about by modernized waterways. The aim of the paper was to present an original methodology for determining port locations for modernized waterways based on non-cost criteria, as an extended multicriteria decision-making method (MCDM) and employing GIS (Geographic Information System)-based tools for spatial analysis. The methodology was designed to be applicable to the varying conditions of a river’s hydroengineering structures (free-flowing river, canalized river, and canals) and adjustable to the requirements posed by intermodal supply chains. The method was applied to study the Odra River Waterway, which allowed the formulation of recommendations regarding the application of the method in the case of different river sections at every stage of the research process.

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