A New Metric for Automated Stability Identification in Time Domain Milling Simulation

2016 ◽  
Vol 138 (7) ◽  
Author(s):  
Andrew Honeycutt ◽  
Tony L. Schmitz
Keyword(s):  
Time Domain ◽  
Forced Vibration ◽  
Stability Limit ◽  
Experimental Results ◽  
The Other ◽  
Sampled Data ◽  
A Value ◽  
Milling Simulation ◽  
The Stability ◽  
Over Time

A new metric is presented to automatically establish the stability limit for time domain milling simulation signals. It is based on periodically sampled data. Because stable cuts exhibit forced vibration, the sampled points repeat over time. Periodically sampled points for unstable cuts, on the other hand, do not repeat with each tooth passage. The metric leverages this difference to define a numerical value of nominally zero for a stable cut and a value greater than zero for an unstable cut. The metric is described and is applied to numerical and experimental results.

Analysis of CTBT IMS Hydroacoustic hydrophone station underwater system electronics calibration sequences

2020 ◽  
Author(s):  
Mario Zampolli ◽  
Georgios Haralabus ◽  
Jerry Stanley ◽  
Peter Nielsen
Keyword(s):  
Cross Talk ◽  
The Other ◽  
System Response ◽  
Electronic Noise ◽  
Laboratory Environment ◽  
Accurate Knowledge ◽  
Ascension Island ◽  
Element Input ◽  
The Stability ◽  
Over Time

<p>The end-to-end calibration from the hydrophone ceramic element input to the digitizer output of CTBT IMS Hydroacoustic (HA) hydrophone stations is measured in a laboratory environment before deployment. After the hydrophones are deployed permanently with the Underwater System (UWS) hydrophone triplets, the response of the digitizer component can be measured by activating remotely a relay which excludes the hydrophone ceramic, preamplifier and riser cable, and feeds a pre-stored known waveform into the digitizer circuit via a digital-to-analogue converter. Analysis of these underwater calibration sequences makes it possible to verify the stability of the digitizer response over time and obtain useful information for investigations which require an accurate knowledge of the system response. Results are presented showing the stability of the UWS electronics response over time and one case, pertaining to the H10S triplet of HA10 Ascension Island, where changes in the calibration response appeared after the onset of electronic noise in one hydrophone channel with cross-talk to the other two channels.</p>

The puzzles of union density in Norway

2007 ◽  
Vol 13 (4) ◽  
pp. 653-670 ◽  
Author(s):  
Kristine Nergaard ◽  
Torgeir Aarvaag Stokke
Keyword(s):  
Labour Market ◽  
Unemployment Insurance ◽  
Union Density ◽  
The Other ◽  
European Countries ◽  
Nordic Region ◽  
Insurance Funds ◽  
Market Factors ◽  
The Stability ◽  
Over Time

The level of union density in Norway is medium high, in contrast to the other Nordic countries where high density levels are supported by unemployment insurance funds. Developments in union density over time are stable in Norway, contrary to developments in most western European countries outside the Nordic region. This article traces the effects of unemployment insurance funds by comparing density levels in Norway with those in Finland and Sweden. In addition, the stability witnessed in union density in Norway over time is a particularly puzzling phenomenon, and the authors seek to explain it on the basis of specific institutional and labour market factors.

Analytical Modeling of Chatter Stability in Turning and Boring Operations—Part II: Experimental Verification

2007 ◽  
Vol 129 (4) ◽  
pp. 733-739 ◽  
Author(s):  
Emre Ozlu ◽  
Erhan Budak
Keyword(s):  
Satisfactory Agreement ◽  
Experimental Verification ◽  
Analytical Modeling ◽  
Stability Limit ◽  
Experimental Results ◽  
Chatter Stability ◽  
Nose Radius ◽  
The Stability ◽  
Flexible Component ◽  
Cutting System

In this part of the paper series, chatter experiments are conducted in order to verify the proposed stability models presented in the first part (Ozlu, E., and Budak, E., 2007, ASME J. Manuf. Sci. Eng., 129(4), pp. 726–732). Turning and boring chatter experiments are conducted for the cases where the tool or the workpiece is the most flexible component of the cutting system. In addition, chatter experiments demonstrating the effect of the insert nose radius on the stability limit are presented. Satisfactory agreement is observed between the analytical predictions and the experimental results.

A Hybrid FETD-FDTD Method with Nonconforming Meshes

2011 ◽  
Vol 9 (3) ◽  
pp. 828-842 ◽  
Author(s):  
Bao Zhu ◽  
Jiefu Chen ◽  
Wanxie Zhong ◽  
Qing Huo Liu
Keyword(s):  
Time Domain ◽  
Fdtd Method ◽  
Stability Limit ◽  
Buffer Zone ◽  
Electric And Magnetic Fields ◽  
Mixed Order ◽  
The Stability ◽  
Conforming Meshes ◽  
Difference Time ◽  
Nonconforming Meshes

AbstractA quasi non-overlapping hybrid scheme that combines the finite-difference time-domain (FDTD) method and the finite-element time-domain (FETD) method with nonconforming meshes is developed for time-domain solutions of Maxwell’s equations. The FETD method uses mixed-order basis functions for electric and magnetic fields, while the FDTD method uses the traditional Yee’s grid; the two methods are joined by a buffer zone with the FETD method and the discontinuous Galerkin method is used for the domain decomposition in the FETD subdomains. The main features of this technique is that it allows non-conforming meshes and an arbitrary numbers of FETD and FDTD subdomains. The hybrid method is completely stable for the time steps up to the stability limit for the FDTD method and FETD method. Numerical results demonstrate the validity of this technique.

Pain patients’ experiences of validation and invalidation from physicians before and after multimodal pain rehabilitation: Associations with pain, negative affectivity, and treatment outcome

2017 ◽  
Vol 17 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Sara M. Edlund ◽  
Matilda Wurm ◽  
Fredrik Holländare ◽  
Steven J. Linton ◽  
Alan E. Fruzzetti ◽  
...  
Keyword(s):  
Treatment Outcome ◽  
Negative Affectivity ◽  
Post Treatment ◽  
Patient Perceptions ◽  
The Other ◽  
Pain Interference ◽  
Before And After ◽  
The Stability ◽  
Pain Patients ◽  
Over Time

AbstractBackground and aimsValidating and invalidating responses play an important role in communication with pain patients, for example regarding emotion regulation and adherence to treatment. However, it is unclear how patients’ perceptions of validation and invalidation relate to patient characteristics and treatment outcome. The aim of this study was to investigate the occurrence of subgroups based on pain patients’ perceptions of validation and invalidation from their physicians. The stability of these perceptions and differences between subgroups regarding pain, pain interference, negative affectivity and treatment outcome were also explored.MethodsA total of 108 pain patients answered questionnaires regarding perceived validation and invalidation, pain severity, pain interference, and negative affectivity before and after pain rehabilitation treatment. Two cluster analyses using perceived validation and invalidation were performed, one on pre-scores and one on post-scores. The stability of patient perceptions from pre- to post-treatment was investigated, and clusters were compared on pain severity, pain interference, and negative affectivity. Finally, the connection between perceived validation and invalidation and treatment outcome was explored.ResultsThree clusters emerged both before and after treatment: (1) low validation and heightened invalidation, (2) moderate validation and invalidation, and (3) high validation and low invalidation. Perceptions of validation and invalidation were generally stable over time, although there were individuals whose perceptions changed. When compared to the other two clusters, the low validation/heightened invalidation cluster displayed significantly higher levels of pain interference and negative affectivity post-treatment but not pre-treatment. The whole sample significantly improved on pain interference and depression, but treatment outcome was independent of cluster. Unexpectedly, differences between clusters on pain interference and negative affectivity were only found post-treatment. This appeared to be due to the pre- and post-heightened invalidation clusters not containing the same individuals. Therefore, additional analyses were conducted to investigate the individuals who changed clusters. Results showed that patients scoring high on negative affectivity ended up in the heightened invalidation cluster post-treatment.ConclusionsTaken together, most patients felt understood when communicating with their rehabilitation physician. However, a smaller group of patients experienced the opposite: low levels of validation and heightened levels of invalidation. This group stood out as more problematic, reporting greater pain interference and negative affectivity when compared to the other groups after treatment. Patient perceptions were typically stable over time, but some individuals changed cluster, and these movements seemed to be related to negative affectivity and pain interference. These results do not support a connection between perceived validation and invalidation from physicians (meeting the patients pre- and post-treatment) and treatment outcome. Overall, our results suggest that there is a connection between negative affectivity and pain interference in the patients, and perceived validation and invalidation from the physicians.ImplicationsIn clinical practice, it is important to pay attention to comorbid psychological problems and level of pain interference, since these factors may negatively influence effective communication. A focus on decreasing invalidating responses and/or increasing validating responses might be particularly important for patients with high levels of psychological problems and pain interference.

scholarly journals STABILITY FOR A SYSTEM OF N FERMIONS PLUS A DIFFERENT PARTICLE WITH ZERO-RANGE INTERACTIONS

2012 ◽  
Vol 24 (07) ◽  
pp. 1250017 ◽  
Author(s):  
M. CORREGGI ◽  
G. DELL'ANTONIO ◽  
D. FINCO ◽  
A. MICHELANGELI ◽  
A. TETA
Keyword(s):  
Quantum System ◽  
Stability Problem ◽  
Relativistic Quantum ◽  
The Other ◽  
Range Interaction ◽  
Symmetric Extension ◽  
A Value ◽  
Zero Range ◽  
Bosonic Case ◽  
The Stability

We study the stability problem for a non-relativistic quantum system in dimension three composed by N ≥ 2 identical fermions, with unit mass, interacting with a different particle, with mass m, via a zero-range interaction of strength α ∈ ℝ. We construct the corresponding renormalized quadratic (or energy) form [Formula: see text] and the so-called Skornyakov–Ter–Martirosyan symmetric extension Hα, which is the natural candidate as Hamiltonian of the system. We find a value of the mass m*(N) such that for m > m*(N) the form [Formula: see text] is closed and bounded from below. As a consequence, [Formula: see text] defines a unique self-adjoint and bounded from below extension of Hα and therefore the system is stable. On the other hand, we also show that the form [Formula: see text] is unbounded from below for m < m*(2). In analogy with the well-known bosonic case, this suggests that the system is unstable for m < m*(2) and the so-called Thomas effect occurs.

scholarly journals First-Principles Calculation on Initial Stage of Oxidation of Si (110)-(1 × 1) Surface

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Takahiro Nagasawa ◽  
Koji Sueoka
Keyword(s):  
First Principles ◽  
Experimental Results ◽  
The Other ◽  
First Principles Calculation ◽  
Preferential Oxidation ◽  
Coverage Ratio ◽  
Surface Areas ◽  
Initial Stage ◽  
The Stability

The initial stage of oxidation of an Si (110)-(1 × 1) surface was analyzed by using the first-principles calculation. Two calculation cells with different surface areas were prepared. In these cells, O atoms were located at the Si–Si bonds in the first layer (A-bonds) and at the Si–Si bonds between the first and second layers (B-bonds). We found that (i) the most stable site of one O atom was the A-bond, and (ii) an O (A-bond) –Si–O (A-bond) was the most stable for two O atoms with a coverage ratio of while an O (A-bond) –Si–O (B-bond) was the most stable for . The stability of O (A-bond) –Si–Si–O (A-bond) was less than the structures obtained in (ii). The other calculations showed that the unoxidized A-bonds should be left when a coverage ratio of is close to 1. These simulations suggest that the O atoms will form clusters in the initial stage of oxidation, and the preferential oxidation will change from the A-bonds to the B-bonds up to the formation of 1 monolayer (ML) oxide. The results obtained here support the reported experimental results.

scholarly journals The Concept of Friend in Publicistics

2020 ◽  
pp. 337-365
Author(s):  
Loreta Vaičiulytė-Semėnienė
Keyword(s):  
Computational Linguistics ◽  
The Other ◽  
Good Time ◽  
Cognitive Approach ◽  
A Value ◽  
In The Beginning ◽  
The Relationship ◽  
Over Time ◽  
Husband And Wife ◽  
What Matters

This article deals with the contents of friend based on the different forms of the noun friend (Lith. draugas). A balance is drawn between the structural and cognitive approach to its meaning. The study is grounded on 700 publicistics sentences collected in the Corpus of the Modern Lithuanian Language compiled by the Centre for Computational Linguistics at Vytautas Magnus University in Kaunas.The study has showed that friend is perceived as a person who acts out of love at a certain place and time.In terms of love, there are friends that are tied (rather) by bonds of fellow-feeling (The Dictionary of the Standard Lithuanian Language – DSLLe friend definition 1, 2) (In the beginning, they were huge friends and liked each other a lot; Friends love you) and those who (rather) share bodily intimacy (DSLLe friend definition 3). On the basis of the criterion of love, the relationship between a person and their friend can revolve in circles: a friend by DSLLe definition 1 or 2 becomes a friend by DSLLe definition 3 (After all, our friends, then families would begin and end in theatre), and vice-versa; a friend by DSLLe definition 2 can become a friend by DSLLe definition 1, and so on. In other words, friendship as fellow-feeling can transform into bodily love, and once bodily love goes away, friends, as husband and wife, can become/remain friends again as very close acquaintances.Someone who loves themselves unconditionally knows how to love another person that way. This kind of friend favours themselves and the other person. Mutual favour unfolds over time spent together, when mutual affinity is found/discovered. That time creates good, real friends that become a value (I treasure good friends the most. We have a bunch of very good mates that we have jolly good time with. We talk, we dance. Or we simply spend time in very comfortable silence).To be a friend, is to become a friend (DSLLe friend definition 1–3 vs. DSLLe friend definition 4). To oneself, first and foremost. The type of friend a person is to themselves is usually revealed through the person’s (myself) relationship with another person they know to a greater or lesser extent. That other person can either be a familiar (DSLLe friend definition 3) or strange (DSLLe friend definition 1, 2) person and/or non-person. Friendship between a person and a thing is a one-way street: it is untrue. What matters in this type of friendship, is not the time spent together, but rather benefit and/or pleasure. In other words, the person (myself) cannot be defined through the understanding of friend, i.e. on the basis of the criterion of similarity: tell me who your friend is, and I will tell you who you are.In terms of time, friends can be defined to a lesser or greater extent (DSLLe friend definition 1, 3 (These friends of father’s go back to Smetona’s era; the friend of my life) resp. DSLLe friend definition 2 (Could it be that she only remained a mere dodgeball friend?)). This is also more or less the case in point when it comes to the aspect of location: well-defined (DSLLe friend definition 3), better-defined (DSLLe friend definition 2; cf.: my roommate) or undefined (DSLLe friend definition 1) friends.The friendship between man and God can be one-way (from God to man) an (become) two-way (between God and man). They both are driven by love, hence are real.

The Comparison of the Reliability of Three Psychometric Scales for Measuring Design Quality

1990 ◽  
Author(s):  
Reva Slaughterbeck Hyde ◽  
Larry Allen Stauffer
Keyword(s):  
Design Problem ◽  
Experimental Results ◽  
The Other ◽  
Design Quality ◽  
Psychometric Scales ◽  
Over Time

Abstract Three scales for subjectively measuring design quality have been developed. Each scale represents a unique strategy for aiding a person in judging the quality of a solution to a design problem. The scales are compared with respect to how reliable these judgements are over time. The experimental results demonstrate that one of the scales is not reliable but that the other two are reliable.

scholarly journals Ciclos económicos y variables monetarias y financieras en México, 1980-2019: un enfoque de cambio estructural

2021 ◽  
Vol 40 (2) ◽  
pp. 137-158
Author(s):  
Reyna Vergara González ◽  
Pablo Mejía Reyes ◽  
Miguel Angel Díaz Carreño
Keyword(s):  
Structural Changes ◽  
Nominal Exchange Rate ◽  
The Other ◽  
Economic Conditions ◽  
Financial Variables ◽  
The Business Cycle ◽  
The Stability ◽  
The Relationship ◽  
Cycle Indicator ◽  
Over Time

El objetivo de este documento es analizar la relación entre el ciclo económico y diversas variables monetarias y financieras con el fin de determinar si han sido estables en el tiempo, teniendo en cuenta los efectos de las modificaciones en las condiciones económicas generales, la estrategia específica adoptada de política monetaria en diferentes subperiodos y las condiciones institucionales en que esta se maneja. Para probar la estabilidad de estas relaciones, una vez que se obtienen los indicadores del ciclo mediante los filtros convencionales, se emplea la metodología de cambio estructural de Bai y Perron (1998). Los resultados destacan dos cambios estructurales en la relación entre el indicador del ciclo y las variables de inflación, tasa de interés, tipo de cambio nominal y agregados monetarios nominales, uno a mediados de los años ochenta y el otro a mediados de los noventa.   Abstract   This paper aims to analyze the relationship between the business cycle and various monetary and financial variables. In particular, the paper seeks to determine whether this relationship has been stable over time, considering the effects of the changes in the general economic conditions, the specific monetary policy strategy adopted in different subperiods, and the institutional framework in which this is managed. To test the stability of these relationships, once the cycle indicators are obtained using conventional filters, the structural change methodology of Bai and Perron (1998) is used. The results highlight two structural changes in the relationship between the cycle indicator and inflation, interest rate, nominal exchange rate, and nominal monetary aggregates, one in the mid-eighties and the other in the middle of the nineties.

Sign in / Sign up

Export Citation Format

Share Document