A TECHNIQUE OF PANELS CUTTING FOR MODIFICATION OF HULL GEOMETRY HYDRODYNAMIC MODELS

2021 ◽  
Vol 162 (A2) ◽  
Author(s):  
H Jafaryeganeh ◽  
C Guedes Soares
Keyword(s):  
Case Studies ◽  
The Body ◽  
Vertical Shear ◽  
Vertical Load ◽  
Load Prediction ◽  
Shear Forces ◽  
Hydrodynamic Models ◽  
Initial Mesh ◽  
Load Effects ◽  
Wave Induced

A panel cutting technique is developed for automatic modification of an initial mesh of a ship hull used for hydrodynamic computations leading to improved meshes for the prediction of wave induced vertical load effects. The technique can provide a model with divided panels in any defined position regardless of the initial discretization of the body. The applications of the provided technique include panel distinction and division in predetermined positions, generation of finer mesh based on the initial coarser model of meshes and improvement of vertical load prediction in predetermined positions. The method is applied for case studies of a barge, shuttle tanker and frigate to depict various applications. Finally, the hydrostatic and hydrodynamic vertical shear forces are calculated for two models of initial and modified panels of well-known frigate 5415. The results are compared for the sections alongside the ship and accuracy of load integration is shown for predetermined sections.

A Technique of Panels Cutting for Modification of Hull Geometry Hydrodynamic Models

2020 ◽  
Vol 162 (A2) ◽  
Author(s):  
H Jafaryeganeh ◽  
C Guedes Soares
Keyword(s):  
Case Studies ◽  
The Body ◽  
Vertical Shear ◽  
Vertical Load ◽  
Load Prediction ◽  
Shear Forces ◽  
Hydrodynamic Models ◽  
Initial Mesh ◽  
Load Effects ◽  
Wave Induced

A panel cutting technique is developed for automatic modification of an initial mesh of a ship hull used for hydrodynamic computations leading to improved meshes for the prediction of wave induced vertical load effects. The technique can provide a model with divided panels in any defined position regardless of the initial discretization of the body. The applications of the provided technique include panel distinction and division in predetermined positions, generation of finer mesh based on the initial coarser model of meshes and improvement of vertical load prediction in predetermined positions. The method is applied for case studies of a barge, shuttle tanker and frigate to depict various applications. Finally, the hydrostatic and hydrodynamic vertical shear forces are calculated for two models of initial and modified panels of well-known frigate 5415. The results are compared for is shown for predetermined sections.

Nonlinear Effects on Long-Term Distributions of Wave-Induced Loads for Tankers

1998 ◽  
Vol 120 (2) ◽  
pp. 65-70 ◽  
Author(s):  
C. Guedes Soares ◽  
T. E. Schellin
Keyword(s):  
Nonlinear Wave ◽  
Nonlinear Effect ◽  
Nonlinear Effects ◽  
Vertical Load ◽  
Load Effects ◽  
Wave Induced

A method of long-term formulation of the nonlinear wave-induced vertical load effects on ships was applied to three tanker hulls of different sizes. For large tanker hulls, the nonlinear effect is not significant, and thus linear theories can continue to be used for earlier studies on these kind of ships, contrary to what was shown earlier for containership hulls. However, for smaller tankers, significant nonlinear values were obtained, with both sagging and hogging nonlinear results being larger than the linear ones.

Experimental and Numerical Study of Wave-Induced Load Effects of Open Ships in Oblique Seas

2011 ◽  
Vol 55 (02) ◽  
pp. 100-123 ◽  
Author(s):  
Suji Zhu ◽  
Mingkang Wu ◽  
Torgeir Moan
Keyword(s):  
Shear Force ◽  
Numerical Study ◽  
Bending Moment ◽  
Vertical Shear ◽  
Torsional Moment ◽  
Numerical Predictions ◽  
Load Effects ◽  
Computer Codes ◽  
Wave Induced ◽  
Vertical Bending Moment

Open ships inherently possess low torsional rigidity because of their open deck structural configuration. Some of the structural failures for open ships are caused by wave-induced torsional moment in combination with other load components in oblique seas. Relatively few experimental results about horizontal bending and torsional moments in oblique seas have been published, however. Further, test data for vertical shear force and vertical bending moment in oblique seas are quite scarce. A backbone model has been recently tested by the Center for Ships and Ocean Structures (CeSOS) in the towing tank and ocean basin at the Marine Technology Center. The model consists of 15 box-shaped segments, in addition to bow and stern segments, which are interconnected by an aluminum beam on the top. Model tests in oblique seas without forward speed were first carried out to provide basic comparisons. Tests in head and oblique seas with speeds were then conducted in regular waves. Irregular wave tests were also carried out to assess the spectral responses and peak distributions of cross-sectional load effects. Load effects at 7 longitudinal positions were measured through strain gauges, including vertical shear force (VSF), vertical bending moment (VBM), horizontal bending moment (HBM), and torsional moment (TM). The motivation of this paper is to perform a benchmark study by comparing numerical predictions of different computer codes with these test results. The uncertainties in the experiments and the computer codes are discussed, and conclusions are presented at the end of this paper.

Feminist Cyber-Artivism, Musicing, and Music Teaching and Learning

2020 ◽  
pp. 291-312
Author(s):  
Marissa Silverman
Keyword(s):  
Social Media ◽  
Music Education ◽  
Case Studies ◽  
Teaching And Learning ◽  
The Body ◽  
The Internet ◽  
Philosophical Investigation ◽  
Music Teaching ◽  
Music Making ◽  
The Voice

This chapter asks an important, yet seemingly illusive, question: In what ways does the internet provide (or not) activist—or, for present purposes “artivist”—opportunities and engagements for musicing, music sharing, and music teaching and learning? According to Asante (2008), an “artivist (artist + activist) uses her artistic talents to fight and struggle against injustice and oppression—by any medium necessary. The artivist merges commitment to freedom and justice with the pen, the lens, the brush, the voice, the body, and the imagination. The artivist knows that to make an observation is to have an obligation” (p. 6). Given this view, can (and should) social media be a means to achieve artivism through online musicing and music sharing, and, therefore, music teaching and learning? Taking a feminist perspective, this chapter interrogates the nature of cyber musical artivism as a potential means to a necessary end: positive transformation. In what ways can social media be a conduit (or hindrance) for cyber musical artivism? What might musicing and music sharing gain (or lose) from engaging with online artivist practices? In addition to a philosophical investigation, this chapter will examine select case studies of online artivist music making and music sharing communities with the above concerns in mind, specifically as they relate to music education.

Effects of Cnoidal Wave-Induced Seepage on Vertical Breakwater Resting on Permeable Elastic Seabed

2014 ◽  
Vol 716-717 ◽  
pp. 284-288
Author(s):  
Jian Kang Yang ◽  
Hua Huang ◽  
Lin Guo ◽  
Jing Rong Lin ◽  
Qing Yong Zhu ◽  
...  
Keyword(s):  
Shallow Water ◽  
Wave Theory ◽  
Cnoidal Wave ◽  
Load Prediction ◽  
Wave Load ◽  
Seepage Pressure ◽  
Theoretical Investigations ◽  
Nonlinearity Effect ◽  
Wave Nonlinearity ◽  
Wave Induced

Theoretical investigations on cnoidal waves interacting with breakwater resting on permeable elastic seabed are presented in this paper. Based on the shallow water reflected wave theory and Biot consolidation theory on wave-induced seepage pressure, the analytical solutions to first order cnoidal wave reflection and wave-induced seepage pressure are obtained by the eigenfunction expansion approach. Numerical results are presented to show the effects of depth of water, breakwater geometry on cnoidal wave-induced seepage uplift force and overturning moment. Compared with Airy wave theory, in certain shallow water conditions, the shallow water wave theory can more effectively illustrate wave nonlinearity effect in wave load prediction.

scholarly journals Ways of Knowing the Body, Bodily Ways of Knowing

2016 ◽  
Vol 22 (2) ◽  
Author(s):  
Peter Martens
Keyword(s):  
Case Studies ◽  
Music Theory ◽  
Music Cognition ◽  
Ways Of Knowing ◽  
Music Analysis ◽  
The Body ◽  
Musical Score ◽  
Research Methodologies

The central role of the body in producing music is hardly debatable. Likewise, the body has always played at least an implicit role in music theory, but has only been raised as a factor in music analysis relatively recently. In this essay I present a brief update of the body in music analysis via case studies, situated in the disciplines of music theory and music cognition, broadly construed. This current trajectory is part of a broader shift away from the musical score as the sole focus for analysis, which admittedly—though, in my view, delightfully—raises a host of challenging epistemological questions surrounding the interaction of performer (production) and listener (perception). While the concomitant research methodologies and technologies may be unfamiliar to scholars trained in humanities disciplines, I advocate for a full embrace of these approaches, either by individual researchers or in the form of cross-disciplinary collaboration.

scholarly journals Successful Surgical Management of Sebaceous Gland Tumours in Dogs

2019 ◽  
Vol 15 (02) ◽  
pp. 78-80
Author(s):  
J. J. Parmar ◽  
AI Shah ◽  
Neha Rao ◽  
DJ Godasara ◽  
DM Patel
Keyword(s):  
Case Studies ◽  
Old Age ◽  
Surgical Management ◽  
Sebaceous Gland ◽  
Surgical Excision ◽  
The Body ◽  
Solitary Lesion ◽  
Veterinary Practice ◽  
Subcutaneous Tissues

Tumors of the skin and subcutaneous tissues are most common in Veterinary practice and account for approximately one-third of all the tumors in dogs (Chikweto et al., 2011). Sebaceous hyperplasia is a most common tumor of the sebaceous gland that occurs in the old age, anywhere on the body as wart-like or cauliflower-like and can become ulcerated because of trauma, while sebaceous epithelioma occurs primarily on the head as a solitary lesion but generalized cases have been reported. The treatment of choice is surgical excision (Max’s House, 2005). This paper presents case studies of sebaceous gland tumors in two dogs.

Articulating Bodies

2019 ◽  
Author(s):  
Kylee-Anne Hingston
Keyword(s):  
Case Studies ◽  
English Translation ◽  
Narrative Structure ◽  
The Body ◽  
Narrative Form ◽  
Victorian Fiction ◽  
Science Technology ◽  
The Social ◽  
Linear Movement ◽  
Body Positioning

Articulating Bodies investigates the contemporaneous developments of Victorian fiction and disability’s medicalization by focusing on the intersection between narrative form and the body. The book examines texts from across the century, from Frederic Shoberl’s 1833 English translation of Victor Hugo’s Notre-Dame de Paris (1831) to Arthur Conan Doyle’s Sherlock Holmes story “The Adventure of the Crooked Man” (1893), covering genres that typically relied upon disabled or diseased characters. By tracing the patterns of focalization and narrative structure across six decades of the nineteenth century and across six genres, Articulating Bodies shows the mutability of the Victorians’ understanding of the human body’s centrality to identity—an understanding made mutable by changes in science, technology, religion, and class. It also demonstrates how that understanding changed along with developing narrative styles: as disability became increasingly medicalized and the soul increasingly psychologized, the mode of looking at deviant bodies shifted from gaping at spectacle to scrutinizing specimen, and the shape of narratives evolved from lengthy multiple-plot novels to slim case studies. Moreover, the book illustrates that, despite this overall linear movement from spectacle to specimen in literature and culture, individual texts consistently reveal ambivalence about categorizing the body, positioning some bodies as abnormally deviant while also denying the reality or stability of normalcy. Bodies in Victorian fiction never remain stable entities, in spite of narrative drives and the social, medical, or scientific discourses that attempted to control and understand them.

Abnormal Wave-Induced Load Effects in Ship Structures

2008 ◽  
Vol 52 (01) ◽  
pp. 30-44 ◽  
Author(s):  
C. Guedes Soares ◽  
N. Fonseca ◽  
R. Pascoal
Keyword(s):  
Extreme Values ◽  
Time History ◽  
Design Criterion ◽  
Freak Waves ◽  
Reference Design ◽  
Load Effects ◽  
Central North Sea ◽  
Wave Induced ◽  
First Time

The paper presents an approach to determine the global load effects induced on shif structures by abnormal, freak, or episodic waves. It refers to the present procedure of determining extreme values of wave-induced responses, including the recent advances of adopting time series of wave elevation as reference design conditions t calculate the wave-induced structural loads on ships in heavy weather. It is show how this procedure can be extended to account for abnormal or episodic waves Reference is made to what is presently known about abnormal or freak waves showing that although it is possible to determine the loads induced by these wave in floating and fixed structures, the present knowledge about the probability of occurrence of these waves is not enough to allow a wave design criterion to be defined in a way consistent with the present probabilistic approaches. However, it is suggested that at the present stage of knowledge it is possible to determine the load induced by abnormal waves similar to ones that have been measured at various ocean locations and that are thus realistic; a method is described to perform such calculations. Although this information cannot replace the wave-induced loads calculated with the presently established procedures, it can serve as guidance for th design. An application example is presented of a containership subjected to a wav trace that includes an episodic wave that was measured during a severe storm in Central North Sea. The measured wave time history is modified in order to investigate the influence of the wave steepness on the induced vertical motions and loads. Th loads induced by the abnormal wave are compared for the first time with extreme values from long-term distributions.

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