Topology Optimization of Dynamic Systems Under Uncertain Loads: An H∞-Norm-Based Approach

2019 ◽  
Vol 14 (2) ◽  
Author(s):  
Paolo Venini
Keyword(s):  
Topology Optimization ◽  
Structural Parameters ◽  
Goal Function ◽  
Dynamic Compliance ◽  
Case Scenario ◽  
Worst Case ◽  
Original Definition ◽  
Optimal Material ◽  
The One ◽  
Definition Of

An innovative approach to topology optimization of dynamic system is introduced that is based on the system transfer-function H∞-norm. As for the structure, the proposed strategy allows to determine the optimal material distribution that ensures the minimization of a suitable goal function, such as (an original definition of) the dynamic compliance. Load uncertainty is accounted for by means of a nonprobabilistic convex-set approach (Ben-Haim and Elishakoff, 1990, Convex Models of Uncertainty in Applied Mechanics, Elsevier Science, Amsterdam). At each iteration, the worst load is determined as the one that maximizes the current dynamic compliance so that the proposed strategy fits the so-called worst case scenario (WCS) approach. The overall approach consists of the repeated solution of the two steps (minimization of the dynamic compliance with respect to structural parameters and maximization of the dynamic compliance with respect to the acting load) until convergence is achieved. Results from representative numerical studies are eventually presented along with extensions to the proposed approach that are currently under development.

What has Natural Information to do with Intentional Representation?

2001 ◽  
Vol 49 ◽  
pp. 105-125 ◽  
Author(s):  
Ruth Garrett Millikan
Keyword(s):  
Informational Semantics ◽  
Original Definition ◽  
Natural Information ◽  
The One ◽  
Definition Of ◽  
Definition Of Information ◽  
Flow Of Information

‘According to informational semantics, if it's necessary that a creature can't distinguish Xs from Ys, it follows that the creature can't have a concept that applies to Xs but not Ys.’ (Fodor, 1994, p. 32)There is, indeed, a form of informational semantics that has this verificationist implication. The original definition of information given in Dretske'sKnowledge and the Flow of Information(1981, hereafter KFI), when employed as a base for a theory of intentional representation or ‘content,’ has this implication. I will argue that, in fact, most of what an animal needs to know about its environment is not available as natural information of this kind. It is true, I believe, that there is one fundamental kind of perception that depends on this kind of natural information, but more sophisticated forms of inner representation do not. It is unclear, however, exactly what ‘natural information’ is supposed to mean, certainly in Fodor's, and even in Dretske's writing. In many places, Dretske seems to employ a softer notion than the one he originally defines. I will propose a softer view of natural information that is, I believe, at least hinted at by Dretske, and show that it does not have verificationist consequences. According to this soft informational semantics, a creature can perfectly well have a representation of Xs without being able to discriminate Xs from Ys.

scholarly journals Intelligent design af fokusgrupper - om metodisk design af fokusgrupper og menneskets forskellige intelligenser

2008 ◽  
Vol 24 (45) ◽  
pp. 13
Author(s):  
Lene Heiselberg
Keyword(s):  
Focus Groups ◽  
Intelligent Design ◽  
Verbal Intelligence ◽  
Case Scenario ◽  
Worst Case ◽  
Apparent Lack ◽  
Self Confidence ◽  
Media Research ◽  
The One ◽  
Interviewing Techniques

Når man arbejder professionelt med at gennemføre kvalitative mini- og fokusgruppeanalyser, kan det ikke undgås, at man som moderator indimellem tænker: Hvorfor deltager hun ikke? Hvad kan jeg gøre for at inkludere hende i diskussionen? Ofte skyldes nogle deltageres manglende engagement, at mini- eller fokusgruppens metodiske design favoriserer de deltagere, som har en fremtrædende verbalsproglig intelligens, og samtidig ekskluderes de, der har andre fremtrædende intelligenser, fra at yde det maksimale. En sådan situation er meget uheldig og kan i værste fald give en undersøgelse bias. Derfor har vi i DR Medieforskning arbejdet med en pragmatisk tilgang til problemet, hvor vi har afprøvet et metodisk design, som inkluderer kvalitative interviewteknikker og procesværktøjer, som appellerer til samtlige intelligenser. Som et resultat af en målrettet indsats for at inkludere flere intelligenser i det metodiske design, oplever vi, at deltagerne har mere lyst til at engagere sig og gør det med større selvsikkerhed. Desuden oplever vi i mindre grad fænomenet “cognitive tuning” , og derfor kan vi arbejde med flere og bedre data i analyse- og fortolkningsfasen. Intelligent design of focus groups - article about methodological design of focus groups and the different intelligences When you work professionally with the conducting and moderating of qualitative mini- and focus groups, you can't avoid sometimes thinking: Why isn’t she participating? What can I do to include her in the discussion? A participant's apparent lack of enthusiasm is often caused by the methodological design of the focus group giving preference to participants who have an explicit verbal intelligence, and as a consequence excludes participants with other explicit intelligences from contributing. A situation like the one described above is very undesirable and in a worst-case scenario it can cause a study to be biased. In order to try to solve this problem DR Media Research applied a methodological design which includes qualitative interviewing techniques and processing tools, which appeal to all of the intelligences instead of just one. As a result of this work, we find that the participants are more eager to participate and that they do it with greater self-confidence. In addition we encounter less cognitive tuning, and are therefore able to work with richer data in the phases of analysis and interpretation.

China positions itself to exploit 'America First'

2017 ◽  
Keyword(s):  
South China Sea ◽  
South China ◽  
North Korea ◽  
The South China Sea ◽  
Strategic Partnership ◽  
Case Scenario ◽  
China Policy ◽  
Worst Case ◽  
Content Type ◽  
The One

Significance Trump affirmed US commitment to the 'one-China policy' vis-à-vis Taiwan, which he had questioned following his election. Nevertheless, Trump's willingness to raise the issue in the first place -- and his other post-election comments on North Korea and the South China Sea -- lead Beijing to expect an unprecedentedly rocky relationship with Washington during his term. Impacts Trump seems now to accept that questioning the one-China policy is taboo, but he could still provoke Beijing regarding Tibet. The combination of uncertain US policy and a China-sceptic government in Taipei will prompt Chinese preparations for a worst-case scenario. US-Russia rapprochement could complicate Beijing's strategic partnership with Moscow. Other governments stand to benefit from a Chinese 'charm offensive', as Beijing attempts to win friends rather than confront Washington.

The Metaphor of Dissociation: Teleological, Phenomenological, Structural, Dynamical

2019 ◽  
pp. 72-105 ◽  
Author(s):  
Ellert R.S. Nijenhuis
Keyword(s):  
Clinical Practice ◽  
Present Article ◽  
Internal Consistency ◽  
Substance Dualism ◽  
Enactive Approach ◽  
Conceptual Clarity ◽  
Original Definition ◽  
Structural Dissociation ◽  
The One ◽  
Definition Of

Dissociation as used in psychology and psychiatry is a troubled conceptual metaphor. The main problems include conflicting definitions and a lack of internal consistency of some of these formulations. Trying to mend the situation, Van der Hart, Nijenhuis and Steele (2006) revisited Janet's original definition of dissociation, and referred to it as "structural dissociation of the personality". This term is not meant to suggest that "structural dissociation" involves a particular kind of dissociation as is sometimes thought. To prevent or repair further misunderstanding, in the present article I highlight four inherent features of dissociation of the personality: teleological, phenomenological, structural, and dynamical. The article alsoaims to bridge some metaphors that are commonly described and understood as dichotomies, implying dualisms that plague philosophy, science, and clinical practice. For example, personality is understood as an organism-environment system, involving subjects and "objects" (that may be other subjects) as co-dependent and co-constitutive partners. Regarding matter (brain/body) and mind as attributes of one substance reflects an attempt to avoid the problems of philosophical (substance) dualism, as well as the one-sidedness of philosophical materialism and idealism. The generation, maintenance, and elaboration ofdissociation is analyzed in terms of causing, that is, the mutual manifestation of a network of reciprocal powers. The joint analyses involve an enactive approach to life, and intend to achieve further conceptual clarity and consistency of the metaphor of dissociation.

A NEW ISOMORPHIC DEFINITION OF THE CROSSED CUBE AND ITS SPANNING CONNECTIVITY

2009 ◽  
Vol 10 (01n02) ◽  
pp. 149-166
Author(s):  
CHENG-KUAN LIN ◽  
CHIEN-PING CHANG ◽  
TUNG-YANG HO ◽  
JIMMY J. M. TAN ◽  
LIH-HSING HSU
Keyword(s):  
Interconnection Network ◽  
Original Definition ◽  
The One ◽  
Definition Of ◽  
Crossed Cube ◽  
Symmetric Properties

In this paper, we propose a slightly different definition of the crossed cube. The interconnection network obtained form our new definition is exactly isomorphic to the one obtained from the original definition proposed by Efe. It is known that the crossed cube is not node symmetric. However, using our new definition, it reveals some relative symmetric properties of the crossed cube. We can take advantage of the symmetry to study the spanning connectivity of the crossed cube.

scholarly journals Digitization: Does It Always Improve Access to Rare Books and Special Collections?

2017 ◽  
Vol 45 (4) ◽  
pp. 177-179 ◽  
Author(s):  
Dale J. Correa
Keyword(s):  
Middle East ◽  
Case Scenario ◽  
Rare Book ◽  
Worst Case ◽  
Special Collections ◽  
State Archives ◽  
The One ◽  
Physical Access ◽  
Conflict Research ◽  
Middle East Studies

Abstract:In April 2016, the Israel State Archives announced the most recent stage of an ambitious project to digitize all of their holdings (potentially 400 million pages of material): the new archival website was ready online (Aderet). With the new website came the ability to request digital copies of documents, which would be available on the website within two weeks of the request (Aderet). However, researchers would now at the very least be discouraged from requesting access to the paper documents (Lozowick), or, in the worst-case scenario, be refused access to anything except the website (Baron and Newhall). Local scholars (including a prominent professor of history at Tel Aviv University), the Akevot Institute for Israeli-Palestinian Conflict Research, and the Middle East Studies Association of North America (which publishes the prestigious International Journal of Middle East Studies) registered concern with the restriction of physical access to the archive and issued public calls for a reversal of the decision (Akevot Institute). The conflict was between perceived best practices of digitization and of archival stewardship (represented by the State Archivist Dr. Yaacov Lozowick) on the one hand, and standards and expectations for scholarly research on the Middle East, which largely depends on archival and rare book collections, on the other.

scholarly journals Robust Topology Optimization of Truss-Like Space Structures

2021 ◽  
pp. 296-306
Author(s):  
Michael Hartisch ◽  
Christian Reintjes ◽  
Tobias Marx ◽  
Ulf Lorenz
Keyword(s):  
Topology Optimization ◽  
Explicit Knowledge ◽  
Programming Model ◽  
Dimensional Space ◽  
Mathematical Optimization ◽  
Space Structures ◽  
Case Scenario ◽  
Worst Case ◽  
Robust Topology Optimization ◽  
Traditional Manufacturing

AbstractDue to the additional design freedom and manufacturing possibilities of additive manufacturing compared to traditional manufacturing, topology optimization via mathematical optimization gained importance in the initial design of complex high-strength lattice structures. We consider robust topology optimization of truss-like space structures with multiple loading scenarios. A typical dimensioning method is to identify and examine a suspected worst-case scenario using experience and component-specific information and to incorporate a factor of safety to hedge against uncertainty. We present a quantified programming model that allows us to specify expected scenarios without having explicit knowledge about worst-case scenarios, as the resulting optimal structure must withstand all specified scenarios individually. This leads to less human misconduct, higher efficiency and, thus, to cost and time savings in the design process. We present three-dimensional space trusses with minimal volume that are stable for up to 100 loading scenarios. Additionally, the effect of demanding a symmetric structure and explicitly limiting the diameter of truss members in the model is discussed.

scholarly journals Being an Italian medical student during the Covid-19 outbreak

2020 ◽  
Author(s):  
Nicolo Giuseppe Biavardi
Keyword(s):  
Medical Student ◽  
Case Scenario ◽  
Academic World ◽  
Worst Case ◽  
Worst Case Scenario ◽  
The World ◽  
E Learning ◽  
The One

Many students around the world have been wondering how their life will change since the very first outbreak of Covid-19. In my experience article I have tried to give a flavor of how has the academic world changed in quarantine. Difficulties and opportunities have been analyzed. Questions regarding the validity of e-learning have been posed. In an arduous period as the one we are experiencing, having an idea of what life could be in worst case scenario could be helpful.

One-stage procedure to establish osseointegration: a zero to five years follow-up report

1995 ◽  
Vol 109 (7) ◽  
pp. 593-598 ◽  
Author(s):  
Anders Tjellström ◽  
Gösta Granström
Keyword(s):  
Success Rate ◽  
Hearing Aids ◽  
Mastoid Process ◽  
Case Scenario ◽  
Two Stage ◽  
Worst Case ◽  
One Stage ◽  
The One ◽  
Lost To Follow Up

AbstractA cohort of 214 patients, who were operated on to insert implants in the mastoid process for the retention of bone-anchored hearing aids and auricular prostheses, was followed-up over a five-year period. About half the group were operated on using the conventional two-stage procedure allowing three to four months for osseointegration. In the second group (one-stage group) the skin penetrating coupling was connected at the time of the implant insertion. The success rate for stable implants was found to be the same in both groups. In the one-stage group four out of 161 implants inserted were lost and in the two stage group three out of 120. The cumulative success rate was also found to be the same. A ‘worst case’ table where patients lost to follow-up, patients who died during the study period, and patients who for some reason left the study is also included. The importance of this ‘worst case’ scenario when follow-up data are presented is discussed.

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