Determination of symmetry relations between higher order material constants for the study of nonlinear acoustic properties of piezoelectric crystals of any symmetry class

This paper reports the results of an ongoing research effort to explain the underlying mechanisms for aeroacoustic fan blade flutter. Using a 3D integrated aeroelasticity method and a single passage blade model that included a representation of the intake duct, the pressure rise vs. mass flow characteristic of a fan assembly was obtained for the 60%–80% speed range. A novel feature was the use of a downstream variable-area nozzle, an approach that allowed the determination of the stall boundary with good accuracy. The flutter stability was predicted for the 2 nodal diameter assembly mode arising from the first blade flap mode. The flutter margin at 64% speed was predicted to drop sharply and the instability was found to be independent of stall effects. On the other hand, the flutter instability at 74% speed was found to be driven by flow separation. Further post-processing of the results at 64% speed indicated significant unsteady pressure amplitude build-up inside the intake at the flutter condition, thus highlighting the link between the acoustic properties of the intake duct and fan blade flutter.

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Analisis Program Pembelajaran Berbasis Higher Order Thinking Skills di MI At-Taqwa GUPPI Wojowalur Daerah Istimewa Yogyakarta Tahun Ajaran 2018/2019

AR-RIAYAH Jurnal Pendidikan Dasar ◽

10.29240/jpd.v5i1.2523 ◽

2021 ◽

Vol 5 (1) ◽

pp. 97

Author(s):

Eka Yusnaldi ◽

Fia Alifah Putri ◽

Wahyu Iskandar

Keyword(s):

Higher Order Thinking ◽

Thinking Skills ◽

Higher Order ◽

Learning Program ◽

Higher Order Thinking Skills ◽

School Year ◽

Implementation Program ◽

Learning Plans ◽

Special Region

The rules 2013 Curriculum is very interested in providing learning processes and items that have Higher Order Thinking Skills (HOTS) degrees for students. The HOTS function is very representative of providing logical, reflective, critical, creative and metacognitive abilities which are higher order thinking abilities. This study aims to determine the HOTS-based learning planning program in MI At-Taqwa GUPPI Wojowalur Yogyakarta Special Region 2018/2019 and HOTS-based learning implementation program in MI At-Taqwa GUPPI Wojowalur Yogyakarta Special Region 2018/2019. Data were analyzed by describing or describing data according to the rules of descriptive qualitative research by taking interview and documentation data. In determining the subject, the researcher used a non-probability sample. The results of this study that (1) HOTS learning program 2018/2019 school year teachers implement learning plans using syllabus and RPP based on HOTS (2) HOTS learning implementation program 2018/2019 school year teachers have used variations in the determination of HOTS-based methods such as discussion, question and answer and students' ability to argue.

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Convergence Study on Application of the Over-Deterministic Method for Determination of Near-Tip Fields in a Cracked Plate Loaded in Mixed-Mode

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.249-250.76 ◽

2012 ◽

Vol 249-250 ◽

pp. 76-81 ◽

Cited By ~ 6

Author(s):

Lucie Šestáková ◽

Václav Veselý

Keyword(s):

Mixed Mode ◽

Brittle Materials ◽

Higher Order ◽

Displacement Fields ◽

Deterministic Method ◽

Crack Behavior ◽

Stress And Displacement Fields ◽

Higher Order Terms ◽

Convergence Study

Multi-parameter description of crack behavior in quasi-brittle materials offers still enough space for investigations. Several studies have been carried out by the authors in this field [1-3]. One part of the publications by the authors (this work included) contain analyses of the accuracy, convergence and/or tuning of the over-deterministic method that enables determination of the coefficients of the higher-order terms in Williams expansion approximating the stress and displacement fields in a cracked body without any complicated FE formulations. These intermediate studies should bring together a list of recommendations how to use the ODM as effectively as possible and obtain reliable enough values of coefficients of the higher-order terms. Thus, the stress/displacement field can be determined precisely even in a larger distance from the crack tip, which is crucial for assessment of the fracture occurring in quasi-brittle materials.

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Precedents for a Theory of Projection

Meter as Rhythm ◽

10.1093/oso/9780190886912.003.0008 ◽

2020 ◽

pp. 127-136

Author(s):

Christopher Hasty

Keyword(s):

Higher Order ◽

Rhythm And Meter ◽

Time Point

This chapter evaluates the work of two theorists who have discussed in detail the phenomenon of “projection.” Friedrich Neumann's concept of the rhythmic pair differs from this book's account of projection most obviously in its isolation of the pair as an autonomous “whole,” its separation of rhythm and meter, and its invocation of time point for the determination of an event's boundaries. Although Neumann describes the process through which a rhythmic pair might become unified as a “higher order” discrimination, he does not consider the process through which equality is produced and removes projection from meter in order to characterize an exclusively rhythmic order that in many respects resembles Hugo Reimann's dynamic, “organic” model. By contrast, Moritz Hauptmann is concerned with the process whereby determinate duration and equality are created and proposes a theory in which meter, quite apart from rhythm, is regarded as a dynamic, organic phenomenon arising from an innate human disposition for equal measure. The chapter then considers Hauptmann's analysis of the formation of duple meter.

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Determination of polymer-solvent interaction parameters using piezoelectric crystals, with reference to the sorption of chemical warfare agents

Journal of Applied Polymer Science ◽

10.1002/app.1993.070470409 ◽

1993 ◽

Vol 47 (4) ◽

pp. 653-665 ◽

Cited By ~ 8

Author(s):

John M. Charlesworth ◽

Stuart Z. Riddell ◽

Robert J. Mathews

Keyword(s):

Chemical Warfare Agents ◽

Chemical Warfare ◽

Interaction Parameters ◽

Solvent Interaction ◽

Piezoelectric Crystals ◽

Warfare Agents ◽

Polymer Solvent

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Apparatus for the Direct Determination of the Dynamic Bulk Modulus

Rubber Chemistry and Technology ◽

10.5254/1.3542696 ◽

1957 ◽

Vol 30 (2) ◽

pp. 449-459

Author(s):

J. E. McKinney ◽

S. Edelman ◽

R. S. Marvin

Keyword(s):

Natural Rubber ◽

Bulk Modulus ◽

Direct Measurement ◽

Static Pressure ◽

Direct Determination ◽

Preliminary Evaluation ◽

Air Bubbles ◽

Frequency Range ◽

Piezoelectric Crystals

Abstract An apparatus has been developed for the direct measurement of the real and imaginary parts of the dynamic bulk modulus of solid and liquid materials over the frequency range of 50 to 10,000 cps. Piezoelectric crystals serving as driver and detector, together with the sample and a confining liquid, are contained in a cavity small compared with the wavelength of sound at these frequencies. Static pressure is superposed to eliminate the effect of small air bubbles. The complex compliances of the sample, confining liquid, and the cavity, are additive in this region, where the compliance is pure dilatation. The dynamic compliances of several natural rubber-sulfur mixtures were obtained in a preliminary evaluation of the behavior of the apparatus.

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