Aeration Effects on Impact: Drop Test of a Flat Plate

Verbatim reproduction or republication of the papers or articles or part of the articles (e.g., figures or tables) by their authors, after the publication or presentation at the ISOPE meetings and journal, is permitted by the International Society of Offshore and Polar Engineers (ISOPE), provided the full credit is given to the authors, to the publisher, The International Society of Offshore and Polar Engineers (ISOPE), and to the Conference, Symposium or Journal - more specifically not to remove the copyright imprint on page 1 of the paper. The permission does not extend to copying for resale and to re-copyrighting the whole or part of the papers. Posting on your organization's website of the paper(s) you specified is allowed only where only your organization's employees including the students can view free of charge the paper authored or co-authored by your organization's employees, and www.isope.org is provided for the paper(s) in the ISOPE proceedings or journals. Regards, Prof. Jin S Chung Executive Director isope, 495 North Whisman Road, Suite 300 Mountain View, California 94043-5711, USA T 1-650-254-1871; F 1-650-254-2038; [email protected] [email protected], www.isope.org www.deepoceanmining.orgAeration effects on impact have been investigated by dropping a flat plate onto the water surface, in which the water is aerated to various degrees. An experimental study has been carried out in the newly commissioned Ocean Basin at Plymouth University’s COAST Lab. The falling block comprises a rigid impact plate connected to two driver plates and its total mass can be varied between 32 kg and 52 kg. The impact plate is 0.25m long, 0.25 m wide and 0.012 m high. The impact velocity is varied between 4 m/s and 7 m/s. Preliminary results of the impact tests are presented here. Visualised results show that there are significant differences between jet formation after impact of the plate in pure water and in aerated water. There is significant reduction of the maximum pressures from those measured in pure water to those measured in aerated water

Methodology for tidal turbine representation in ocean circulation model

The present method proposes the use and adaptation of ocean circulation models as an assessment tool framework for tidal current turbine (TCT) array layout optimization. By adapting both momentum and turbulence transport equations of an existing model, the present TCT representation method is proposed to extend the actuator disc concept to 3-D large-scale ocean circulation models. Through the reproduction of experimental flume tests and grid dependency tests, this method has shown its numerical coherence as well as its ability to simulate accurately both momentum and turbulent turbine-induced perturbations in both near and far wakes in a relatively short period of computation time. Consequently the present TCT representation method is a very promising basis for the development of a TCT array layout optimization tool

Development of four-dimensional atmospheric models (worldwide)

Development of four dimensional atmospheric models from global data for predicting atmospheric attenuation encountered by earth resources observation sensor

Integrated Numerical Modelling System for Extreme Wave Events at the Wave Hub Site

This paper examines an extreme wave event which occurred during a storm at the Wave Hub site in 2012. The extreme wave of 9.57 m height was identified from a time series of the heave data collected by an Oceanor Seawatch Mini II Buoy deployed at the site. An energy density spectrum was derived from this time series and then used to drive a physical model, which represents the extreme wave at 1:20 scale in Plymouth University’s new COAST Lab. The NewWave technique was used to define the input to the physical model. The experiment is reproduced in a numerical wave tank using the fully nonlinear CFD library OpenFOAM® and the wave generation toolbox waves2Foam. Results are evaluated, and issues regarding the predictions of a numerical model that is driven by the NewWave input signal are discussed. This study sets the basis for further research in coupling field data, physical modelling and numerical modelling in a more efficient and balanced way. This will lead to the new approach of composite modelling that will be implemented in future work

Archaeological Survey of Three Land Parcels and Shovel Testing of Four Sites at Camp Bowie, Brown County, Texas

Pedestrian survey and shovel testing of three land parcels and shovel testing of four previously identified archaeological sites in Camp Bowie, Brown County, Texas, was performed by the Center for Archaeological Research (CAR) at The University of Texas at San Antonio during October and November of 2001. This work, conducted under Texas Antiquities Permit No. 2310, was undertaken as a result of recommendations from Wormser and Sullo-Prewitt (2001) following their archaeological survey and site recording efforts. Three areas of Camp Bowie were surveyed and shovel tested. Parcel 1 is 74 acres (30 ha) in extent and 46 shovel tests were excavated in this area. One new site (41BR522) was identified at the northern margin of this survey area. 41BR522 is a small burned rock midden site. Seven additional shovel tests were excavated on this site. One Late Prehistoric projectile point fragment was recovered during shovel testing of 41BR522. Excluding the units on 41BR522, only three shovel tests within Parcel 1 contained subsurface lithics. All of these artifacts represent isolated finds (IF). One additional shovel test had a single animal bone that may not be cultural and is considered an IF. Parcel 2 covers 64 acres (26 ha) and 33 shovel tests were placed within this area. None of the shovel tests in Parcel 2 produced any subsurface archaeological material. Parcel 3 is 62 acres (25 ha) and 43 shovel tests were excavated in this part of Camp Bowie. One shovel test produced two heat-fractured lithics that are not unambiguously cultural in origin. 41BR522 is recommended for additional testing to determine its State Archeological Landmark (SAL) and National Register of Historic Places (NRHP) eligibility. None of the other areas of the three survey parcels contain cultural resources that are considered SAL or NRHP eligible. In the event of deep or extensive excavation of the alluvial soils in Parcel 1, archaeological monitoring is recommended to identify any potential impacts to resources below the 60 cm depth investigated by this project. Normal military use of this area may proceed without further consultation with the Texas Historical Commission (THC). In response to recommendations by Wormser and Sullo-Prewitt (2001), four previously recorded archaeological sites were revisited (41BR248, 41BR467, 41BR469, and 41BR471). Site 41BR248 could not be relocated. No surface or subsurface artifacts were identified at the plotted site location. Four shovel tests were excavated within the identified site location, but no cultural materials were encountered. Either naturally fractured local chert has been mistaken for cultural artifacts or the plotted location is not correct for 41BR248. Four shovel tests were excavated in 41BR467, a low-density lithic scatter. No artifacts were recovered from the shovel tests. Four bifaces and two cores were recovered from the surface of this site. Six shovel tests were placed on 41BR469, a low-density lithic scatter. One shovel test contained a single subsurface flake. 41BR471 is a small, relatively dense lithic scatter. Four shovel tests were excavated on this site. One shovel test contained a single lithic. There were no other indications of subsurface archaeological deposits. Surface artifacts included one Late Prehistoric projectile point. Surface visibility at these sites exceeded 30 percent and the number of shovel tests is considered sufficient to determine the significance of these cultural resources. 41BR248 could not be identified at its previously plotted location, if this site still exists –it requires relocation and testing. Additional examination is recommended for 41BR471. Following re-examination and testing, no further characterization of 41BR467 and 41BR469 is considered necessary. With the exception of 41BR471 and 41BR248, no further archaeological work is recommended and scheduled use of this area may proceed without further consultation with THC. Two additional sites, re-examined in February of 2001 to determine their SAL and NRHP eligibility, are also included in this report (41BR392 and 41BR523). Two shovel tests were excavated in 41BR392 to examine a prehistoric burned rock midden at this previously identified historic site. One Middle Archaic Bulverde point was recovered from the surface of 41BR392. 41BR523 is a World War II-era live grenade court. This site was described but no shovel tests were considered necessary. Further testing is recommended for the burned rock midden component of 41BR392. No additional archaeological work is considered necessary on 41BR523 and that location is recommended for archaeological clearance. Recommendations from this project are that the SAL and NRHP eligibility of 41BR392, 41BR471, and 41BR522 is unclear in the absence of additional testing efforts. These sites should be protected and avoided until additional examination can determine their SAL and NRHP eligibility status. 41BR248 could not be located with the information currently available. Additional evaluation of this site is still required in relation to previous recommendations by THC. Sites 41BR467, 41BR469, and 41BR523 are considered ineligible as SAL or NRHP properties and no additional archaeological characterization is considered necessary. The three survey parcels examined during this survey and testing project do not contain any significant cultural properties (other than 41BR522 at the periphery of Parcel 1) detectable through shovel testing methods. Parcel 1 is located on deep alluvial soil that could contain deeply buried archaeological deposits. Archaeological monitoring is recommended to identify any potential cultural resources below the 60 cm depth investigated in Parcel 1 if significant excavation of this area is planned. Normal military use of these areas may proceed without further consultation with THC

Information-theoretic measures as a generic approach to human-robot interaction : Application in CORBYS project

Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the Owner/AuthorThe objective of the CORBYS project is to design and implement a robot control architecture that allows the integration of high-level cognitive control modules, such as a semantically-driven self-awareness module and a cognitive framework for anticipation of, and synergy with, human behaviour based on biologically-inspired information-theoretic principles. CORBYS aims to provide a generic control architecture to benefit a wide range of applications where robots work in synergy with humans, ranging from mobile robots such as robotic followers to gait rehabilitation robots. The behaviour of the two demonstrators, used for validating this architecture, will each be driven by a combination of task specific algorithms and generic cognitive algorithms. In this paper we focus on the generic algorithms based on information theoryFinal Accepted Versio

Co-located wave and offshore wind farms: A preliminary approach to the shadow effect

In recent years, with the consolidation of offshore wind technology and the progress carried out for wave energy technology, the option of combine both technologies has arisen. This combination rest mainly in two main reasons: in one hand, to increase the sustainability of both energies by means of a more rational harnessing of the natural resources; in the other hand, to reduce the costs of both technologies by sharing some of the most important costs of an offshore project. In addition to these two powerful reasons there are a number of technology synergies between wave and wind systems which makes their combination even more suitable. Co-located projects are one of the alternatives to combine wave-wind systems, and it is specially for these project were so-called shadow effect synergy becomes meaningful. In particular, this paper deals with the co-location of Wave Energy Conversion (WEC) technologies into a conventional offshore wind farm. More specifically, an overtopping type of WEC technology was considered in this work to study the effects of its co-location with a conventional offshore wind park. This study aims to give a preliminary approach to the shadow effect and its implications for both wave and offshore wind energies

CO-LOCATED WAVE AND OFFSHORE WIND FARMS: A PRELIMINARY CASE STUDY OF AN HYBRID ARRAY

In recent years, with the consolidation of offshore wind technology and the progress carried out for wave energy technology, the option of co-locate both technologies at the same marine area has arisen. Co-located projects are a combined solution to tackle the shared challenge of reducing technology costs or a more sustainable use of the natural resources. In particular, this paper deals with the co-location of Wave Energy Conversion (WEC) technologies into a conventional offshore wind farm. More specifically, an overtopping type of WEC technology was considered in this work to study the effects of its co-location with a conventional offshore wind park

Bearing Signal Separation of Commercial Helicopter Main Gearbox

Gears are significant component in a multiplicity of industrial applications such as machine tool and gearboxes. An unforeseen failure of gear may result in significant economic losses. Therefore this research propose fault detection improvement throught series of vibration signal processing techuiques. These techniques have been tested experimentally using vibration data collected from the transmission system of a CS-29 ‘Category A’ helicopter gearbox under different bearing damage severity of the second planetary stage. Results showed successful improvement of bearing fault detection