scholarly journals Preliminary Study of Ship Maneuvering Prediction of Container Ship

2021 ◽  
Vol 1052 (1) ◽  
pp. 012001
Author(s):  
A N Yulianto ◽  
W D Aryawan ◽  
T Putranto ◽  
S H Sujiatanti ◽  
G M Ahadyanti ◽  
...  
Author(s):  
Rameesha Thayale Veedu ◽  
Parameswaran Krishnankutty

Ship maneuvering performance is usually predicted in calm water conditions, which provide valuable information about ship’s turning ability and its directional stability in the early design stages. Investigation of maneuvering simulation in waves is more realistic since the ship usually sails through waves. So it is important to study the effect of waves on the turning ability of a ship. This paper presents the maneuvering simulation for a container ship in presence of regular waves based on unified state space model for ship maneuvering. Standard maneuvers like turning circle and zigzag maneuver are simulated for the head sea condition and the same are compared with calm water maneuvers. The present study shows that wave significantly affects the maneuvering characteristics of the ship and hence cannot be neglected.


Author(s):  
Rameesha Thayale Veedu ◽  
Parameswaran Krishnankutty

Evaluation of maneuverability of a ship at the early design stages is necessary for ensuring safety of its voyage. IMO recommends the test speed or approach speed for the maneuvering predictions as 90–100% of the service speed of the vessel. The confined model tests for ship maneuvering assessment are usually conducted at low speeds and the hydrodynamic derivatives obtained from these tests are used in the equation of motion even when vessel operates at much higher speeds. But the hydrodynamic derivatives and consequently the trajectory predicted using these derivatives differ substantially from the actual maneuvering conditions. Hence the dependency of the derivatives on vessel speed needs to be understood properly to get the correct estimate of the vessel trajectory prediction. This paper investigates the effect of vessel speed (Fn) on hydrodynamic characteristics of a container ship. Straightline test and horizontal planar motion mechanism (HPMM) tests are conducted for a container ship model for different speeds in a CFD environment.


Author(s):  
John H.L. Watson ◽  
John L. Swedo ◽  
R.W. Talley

A preliminary study of human mammary carcinoma on the ultrastructural level is reported for a metastatic, subcutaneous nodule, obtained as a surgical biopsy. The patient's tumor had responded favorably to a series of hormonal therapies, including androgens, estrogens, progestins, and corticoids for recurring nodules over eight years. The pertinent nodule was removed from the region of the gluteal maximus, two weeks following stilbestrol therapy. It was about 1.5 cms in diameter, and was located within the dermis. Pieces from it were fixed immediately in cold fixatives: phosphate buffered osmium tetroxide, glutaraldehyde, and paraformaldehyde. Embedment in each case was in Vestopal W. Contrasting was done with combinations of uranyl acetate and lead hydroxide.


Author(s):  
H.D. Geissinger ◽  
C.K. McDonald-Taylor

A new strain of mice, which had arisen by mutation from a dystrophic mouse colony was designated ‘mdx’, because the genetic defect, which manifests itself in brief periods of muscle destruction followed by episodes of muscle regeneration appears to be X-linked. Further studies of histopathological changes in muscle from ‘mdx’ mice at the light microscopic or electron microscopic levels have been published, but only one preliminary study has been on the tibialis anterior (TA) of ‘mdx’ mice less than four weeks old. Lesions in the ‘mdx’ mice vary between different muscles, and centronucleation of fibers in all muscles studied so far appears to be especially prominent in older mice. Lesions in young ‘mdx’ mice have not been studied extensively, and the results appear to be at variance with one another. The degenerative and regenerative aspects of the lesions in the TA of 23 to 26-day-old ‘mdx’ mice appear to vary quantitatively.


Author(s):  
J P Cassella ◽  
V Salih ◽  
T R Graham

Left ventricular assist systems are being developed for eventual long term or permanent implantation as an alternative to heart transplantation in patients unsuitable for or denied the transplant option. Evaluation of the effects of these devices upon normal physiology is required. A preliminary study was conducted to evaluate the morphology of aortic tissue from calves implanted with a pneumatic Left Ventricular Assist device-LVAD. Two 3 month old heifer calves (calf 1 and calf 2) were electively explanted after 128 days and 47 days respectively. Descending thoracic aortic tissue from both animals was removed immediately post mortem and placed into karnovsky’s fixative. The tissue was subsequently processed for transmission electron microscopy (TEM). Some aortic tissue was fixed in neutral buffered formalin and processed for routine light microscopy.


2021 ◽  
Author(s):  
Hicham Zaroual ◽  
El Mestafa El Hadrami ◽  
Romdhane Karoui

This study examines the feasibility of using front face fluorescence spectroscopy (FFFS) to authenticate 41 virgin olive oil (VOO) samples collected from 5 regions in Morocco during 2 consecutive crop seasons.


2019 ◽  
Vol 28 (2S) ◽  
pp. 915-924 ◽  
Author(s):  
Kristie A. Spencer ◽  
Mallory Dawson

Purpose This preliminary study examined whether speech profiles exist for adults with hereditary ataxia based on 2 competing frameworks: a pattern of instability/inflexibility or a pattern of differential subsystem involvement. Method Four dysarthria experts rated the speech samples of 8 adults with dysarthria from hereditary ataxia using visual analog scales and presence/severity rating scales of speech characteristics. Speaking tasks included diadochokinetics, sustained phonation, and a monologue. Results Speech profiles aligned with the instability/inflexibility framework, with the pattern of instability being the most common. Speech profiles did not emerge for the majority of speakers using the differential subsystem framework. Conclusions The findings extend previous research on pure ataxic dysarthria and suggest a possible framework for understanding the speech heterogeneity associated with the ataxias. The predominance of the instability profile is consistent with the notion of impaired feedforward control in speakers with cerebellar disruption.


2020 ◽  
Vol 5 (5) ◽  
pp. 1221-1230
Author(s):  
Jane Roitsch ◽  
Kimberly A. Murphy ◽  
Anastasia M. Raymer

Purpose The purpose of this study was to investigate executive function measures as they relate to clinical and academic performance outcomes of graduate speech-language pathology students. Method An observational design incorporating correlations and stepwise multiple regressions was used to determine the strength of the relationships between clinical outcomes that occurred at various time points throughout the graduate program (clinical coursework grades throughout the program and case study paper scores at the end of the program), academic outcomes (graduate grade point average and Praxis II exam in speech-language pathology scores), and executive function (EF) scores (EF assessment scores, self-reported EF scores). Participants were 37 students (36 women, M age = 24.1) in a master's degree program in speech-language pathology at a southeastern U.S. university during the 2017–2018 academic year. Results Findings of this preliminary study indicated that a limited number of objective EF scores and self-reported EF scores were related to clinical and academic outcomes of graduate speech-language pathology students. Conclusion As results of this preliminary study suggest that EF tests may be related to clinical and academic outcomes, future research can move to study the potential role of EF measures in the graduate admissions process in clinical graduate programs such as speech-language pathology.


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