scholarly journals Evaluating the impact of gillnet ghost fishing using a computational analysis of the geometry of fishing gear

2007 ◽  
Vol 64 (8) ◽  
pp. 1517-1524 ◽  
Author(s):  
Tsutomu Takagi ◽  
Takashi Shimizu ◽  
Holger Korte
Keyword(s):  
Computational Analysis ◽  
Three Dimensional ◽  
Fishing Gear ◽  
Capture Process ◽  
Gear Design ◽  
Sea Bottom ◽  
Dimensional Shape ◽  
Internal Forces ◽  
Analysis System ◽  
The Impact

Abstract Takagi, T., Shimizu, T., and Korte, H. 2007. Evaluating the impact of gillnet ghost fishing using a computational analysis of the geometry of fishing gear. – ICES Journal of Marine Science, 64: 1517–1524. We developed a net shape and load analysis system (NaLA) that can estimate the three-dimensional shape of fishing gear underwater computationally. This paper introduces the latest version of the numerical model of the NaLA. Previously, NaLA was used to estimate the net geometries and internal forces of some fishing gear, demonstrating its general versatility. However, the ultimate goal of our study has been to learn about the impact of fishing and the capture process from a physical perspective, not simply to develop elemental technologies for gear design. Accurate, quantitative evaluation of fishing gear performance from a physical perspective can be used to estimate the potentialities of the ghost fishing to gillnet gears. Although the applications are not limited to geometries and internal forces, the paper describes how computer-aided simulations of fishing gear should be applied to investigations of the impact of ghost fishing caused by lost drift and bottom gillnets. The computational results showed that a driftnet with homogenous net panels was deformed slightly and bent only at the two ends of the net. Accumulation of periphyton on a bottom gillnet after 25 d of immersion caused it to settle to the sea bottom.

scholarly journals Detection of therapeutic radiation in three-dimensions

2017 ◽  
Vol 13 ◽  
pp. 1325-1331 ◽  
Author(s):  
John A Adamovics
Keyword(s):  
State Of The Art ◽  
Three Dimensional ◽  
The State ◽  
Three Dimensions ◽  
Radical Initiator ◽  
Radiation Delivery ◽  
Dimensional Shape ◽  
Therapeutic Radiation ◽  
The Impact ◽  
Three Dimensional Shape

For over the last twenty years there has been a multitude of sophisticated three-dimensional radiation delivery procedures developed which requires a corresponding verification of the impact on patients. This article reviews the state of the art in the development of chemical detectors used to characterize the three-dimensional shape of therapeutic radiation. These detectors are composed of polyurethane, radical initiator and a leuco dye, which is radiolytically oxidized to a dye absorbing at 630 nm.

scholarly journals The Impact of Airborne Radio Occultation Observations on the Simulation of Hurricane Karl (2010)

2018 ◽  
Vol 146 (1) ◽  
pp. 329-350 ◽  
Author(s):  
X. M. Chen ◽  
S.-H. Chen ◽  
J. S. Haase ◽  
B. J. Murphy ◽  
K.-N. Wang ◽  
...  
Keyword(s):  
Radio Occultation ◽  
Three Dimensional ◽  
Wrf Model ◽  
Tangent Point ◽  
Sea Level Pressure ◽  
Analysis System ◽  
The Tropics ◽  
Ray Path ◽  
The Impact ◽  
First Time

Abstract This study evaluates, for the first time, the impact of airborne global positioning system radio occultation (ARO) observations on a hurricane forecast. A case study was conducted of Hurricane Karl during the Pre-Depression Investigation of Cloud-Systems in the Tropics (PREDICT) field campaign in 2010. The assimilation of ARO data was developed for the three-dimensional variational (3DVAR) analysis system of the Weather Research and Forecasting (WRF) Model version 3.2. The impact of ARO data on Karl forecasts was evaluated through data assimilation (DA) experiments of local refractivity and nonlocal excess phase (EPH), in which the latter accounts for the integrated horizontal sampling along the signal ray path. The tangent point positions (closest point of an RO ray path to Earth’s surface) drift horizontally, and the drifting distance of ARO data is about 2 to 3 times that of spaceborne RO, which was taken into account in these simulations. Results indicate that in the absence of other satellite observations, the assimilation of ARO EPH resulted in a larger impact on the analysis than local refractivity did. In particular, the assimilation of ARO observations at the actual tangent point locations resulted in more accurate forecasts of the rapid intensification of the storm. Among all experiments, the best forecast was obtained by assimilating ARO data with the most accurate geometric representation, that is, the use of nonlocal EPH operators with tangent point drift, which reduced the error in the storm’s predicted minimum sea level pressure (SLP) by 43% beyond that of the control experiment.

scholarly journals Design of Active Frequency Selective Surface with Curved Composite Structures and Tunable Frequency Response

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
In-Gon Lee ◽  
Yong Bae Park ◽  
Heung-Jae Chun ◽  
Yoon-Jae Kim ◽  
Ic-Pyo Hong
Keyword(s):  
Composite Structures ◽  
Three Dimensional ◽  
Frequency Selective Surface ◽  
Control Technique ◽  
X Band ◽  
Via Holes ◽  
Dimensional Shape ◽  
Frequency Selective ◽  
Tunable Frequency ◽  
The Impact

We present an active frequency selective surface (AFSS) consisting of a curved composite structure that provides structural stability and robustness. The proposed structure can operate on either the C-band (OFF state) or X-band (ON state) by controlling the PIN diode located between the cross-shaped loop and the inductive stub on the surface. Moreover, it minimizes parasitic couplings through grid-type on/off bias circuits and via holes. Thus, the AFSS guarantees isolation from the unit cell, which is a downside of a previous control technique called reconfigurable frequency selective surface. We analyzed the impact of composite structures and the three-dimensional shape on the AFSS transmission with a foam-core sandwich structure, which is light and mechanically strong, by considering conditions of a real application environment.

Evaluation of the Impact of Observations on Analyses in 3D- and 4D-Var Based on Information Content

2011 ◽  
Vol 139 (3) ◽  
pp. 726-737 ◽  
Author(s):  
Cristina Lupu ◽  
Pierre Gauthier ◽  
Stéphane Laroche
Keyword(s):  
Data Assimilation ◽  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Practical Method ◽  
A Posteriori ◽  
Error Statistics ◽  
One Dimensional ◽  
Complete Set ◽  
Analysis System ◽  
The Impact

Abstract The degrees of freedom for signal (DFS) is used in data assimilation applications to measure the self-sensitivity of analysis to different observation types. This paper describes a practical method to estimate the DFS of observations from a posteriori statistics. The method does not require the consistency of the error statistics in the analysis system and it is shown that the observational impact on analyses can be estimated from observation departures with respect to analysis or the forecast. This method is first introduced to investigate the impact of a complete set, or subsets, of observations on the analysis for idealized one-dimensional variational data assimilation (1D-Var) analysis experiments and then applied in the framework of the three dimensional (3D)- and four-dimensional (4D)-Var schemes developed at Environment Canada.

Measurement and Three-Dimensional Computational Analysis for Flow Electrification in Complex-Shaped Ducts

2016 ◽  
Vol 136 (3) ◽  
pp. 318-324
Author(s):  
Naoya Miyamoto ◽  
Makoto Koizumi ◽  
Hiroshi Miyao ◽  
Takayuki Kobayashi ◽  
Kojiro Aoki
Keyword(s):  
Computational Analysis ◽  
Three Dimensional ◽  
Flow Electrification

Four Dimensions of Diamond T: Combination Trade Marks of Colours And Shapes

2006 ◽  
Vol 37 (4) ◽  
pp. 583
Author(s):  
Michael McGowan
Keyword(s):  
Three Dimensional ◽  
Trade Mark ◽  
Fourth Dimension ◽  
Trade Marks ◽  
Four Dimensions ◽  
Trade Mark Law ◽  
Dimensional Shape ◽  
Three Dimensional Shape

This article examines the relatively new fields of colour and shape trade marks. It was initially feared by some academics that the new marks would encroach on the realms of patent and copyright.  However, the traditional requirements of trade mark law, such as functionality and descriptiveness, have meant that trade marks in colour and shape are extremely hard to acquire if they do not have factual distinctiveness. As colour and shape trade marks have no special restrictions, it is proposed that the combination trade mark theory and analysis from the Diamond T case should be used as a way to make them more accessible. The combination analysis can be easily applied because every product has a three dimensional shape and a fourth dimension of colour.

Analyzing the Impact of X-Ray Tomography on the Reliability of Integrated Circuits

2015 ◽  
Author(s):  
Halit Dogan ◽  
Md Mahbub Alam ◽  
Navid Asadizanjani ◽  
Sina Shahbazmohamadi ◽  
Domenic Forte ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
3D Imaging ◽  
Three Dimensional ◽  
Serial Sectioning ◽  
Promising Technique ◽  
Flash Memories ◽  
X Ray ◽  
3D Information ◽  
The Impact

Abstract X-ray tomography is a promising technique that can provide micron level, internal structure, and three dimensional (3D) information of an integrated circuit (IC) component without the need for serial sectioning or decapsulation. This is especially useful for counterfeit IC detection as demonstrated by recent work. Although the components remain physically intact during tomography, the effect of radiation on the electrical functionality is not yet fully investigated. In this paper we analyze the impact of X-ray tomography on the reliability of ICs with different fabrication technologies. We perform a 3D imaging using an advanced X-ray machine on Intel flash memories, Macronix flash memories, Xilinx Spartan 3 and Spartan 6 FPGAs. Electrical functionalities are then tested in a systematic procedure after each round of tomography to estimate the impact of X-ray on Flash erase time, read margin, and program operation, and the frequencies of ring oscillators in the FPGAs. A major finding is that erase times for flash memories of older technology are significantly degraded when exposed to tomography, eventually resulting in failure. However, the flash and Xilinx FPGAs of newer technologies seem less sensitive to tomography, as only minor degradations are observed. Further, we did not identify permanent failures for any chips in the time needed to perform tomography for counterfeit detection (approximately 2 hours).

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