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2 kHz high power smart transducer for acoustic sub-bottom profiling applications

In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response（TCR） at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility（ATF） of National Institute of Ocean Technology（NIOT） for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.     

Groups in DEA based cross-evaluation: An application to Asian container ports

In container port performance evaluation, a group of ports in one country is always significantly different from a group of ports in another country. This is noticed as the heterogeneity of port performance. It is therefore necessary to further investigate the impact of the different groups on efficiency evaluation of ports. The cross-evaluation method is a DEA extension tool to identify best performing DMUs and to rank DMUs using cross efficiency scores linked to all DMUs. A factor that possibly reduces the usefulness of the cross efficiency evaluation method is that cross efficiency scores may not be unique due to the presence of alternative optima. Doyle and Green 1 Doyle, J and Green, R. 1994. Efficiency and cross efficiency in DEA: Derivations, meanings and uses. Journal of the Operational Research Society, 45: 567–578. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar] propose the use of secondary goals to deal with the non-uniqueness issue by the aggressive/benevolent model formulations. This article extends the model of Doyle and Green by considering the groups of DMUs in the determination of final cross efficiency. A new approach based on cross efficiency evaluation method is developed and applied to efficiency analysis of 28 container ports from 12 countries in Asia. A comparative study between traditional and newly proposed methods is conducted.     

Designing Coastal Management Strategies for Populations with Distinct Needs: The Case of Learning Disabilities

The Disability Discrimination Act (1995, amended 2005), Equality Act (2010 Equality Act. 2010. Equality Act. http://www.legislation.gov.uk/ukpga/2010/15/contents#openingWholeMod (accessed May 17, 2012) [Google Scholar]), EU Disability Action Plan (2003 –2010), and EU Disability Strategy (2010–2020) were designed to make equal opportunities a “reality.” As 16% of the EU population, is statutorily disabled there are considerable implications for beach management. Research examples of beach users include swimmers, anglers, etc. - but rarely people with learning disabilities (LD). This paper considered beach users with LD and their appreciation of three different coastal classifications in South Wales. Because of their disabilities, the research applied a participatory photo interpretation methodology (photovoice). A comparison of the LD ranking of beach issues was made with rankings provided by the general public at the same beaches. Results demonstrated some similarities between LD and general public coastal needs, but identified the need for specific considerations to be made by beach managers for LD users, including informed self-advocacy, use/application of signage, instructive access and a requirement for baseline information gathering. The research proposes an integrated coastal access model from which coastal management/gatekeepers can consider LD needs within coastal strategies. Finally, findings highlight the use of photovoice in coastal research projects and the need for innovative methodological considerations when researching certain groups.     

The distribution of the benefits of waterfront reform

In this paper we introduce, for the first time, a methodology from the most recent literature of finance to reveal the duration of shipping cycles and then show the benefit of the use of this information to make more successful shipping loans. This is so as banks are willing to finance, during boom periods, shipping loans for new buildings but by this way ‘create’ oversupply and thus depress the freight market by their own actions. The information about cycles, especially their forecasting, is mostly important as shipping loans are based on project financing/cash flow financing, which means that ship revenue is of utmost importance. The Rescaled Range Analysis is applied here to 379 monthly freight trips—made stationary—between 1971 and 2002 (July), due to Hurst 1 Hurst, HE. 1950. Long-term storage capacity of reservoirs. April1950. pp.770–808. American Society of Civil Engineers. Paper No. 2447 [Google Scholar] and elaborated and popularized by Mandelbrot 2 Mandelbrot, BB. 1975. Stochastic models for the earth's relief, the shape and the fractal dimensions of the coastlines, and the number-area rule for islands. Proceedings of the National Academy of Sciences. 1975, USA 72. pp.3825–3828. [Crossref] , [Google Scholar]. The most important effect, however, is that shipping freight series exhibit non-normality and long-run dependence rendering the use of random walk models such as GARCH (Generalized Autoregressive Conditional Heteroscedasticity) problematic. Thus an adequate literature review is carried out with criticism against the models used. The cycles have been calculated as equal to 4.5 years and 2.25 years. This is almost compatible with the most recent paper of Stopford 3 Stopford, M. 21 September 2001. “Forecasting the dry bulk, tanker and container markets”. In Maritime Cyprus 21 September,  [Google Scholar]. The Hurst exponent was found equal to 0.93, alternating over the periods examined (0.65, 0.73, 0.62, 0.59 and 0.55) and indicating long-term persistence but seriously away from normal/random walk domain. Most studies have said the same using the Jarque--Bera test for normality but provided no alternative.     

An Assessment of Integrated Coastal Management Governance and Implementation Using the DPSIR Framework: KwaZulu-Natal,South Africa

Coastal areas are under increasing pressure driven by demands for coastal space, primarily though population growth, in migration and the need for space for socioeconomic activities. The pressures and associated changes to the coastal environment need to be managed to ensure long-term sustainability. South Africa has enacted an Integrated Coastal Management Act (ICM Act) to facilitate dedicated management of its coastal environment. The implementation has been met with a number of challenges, primarily relating to financial and human capacity constraints, particularly at the local government level. Given that the ICM Act devolves powers to local government, it is imperative that implementation challenges be addressed. This paper focuses on KwaZulu-Natal, one of four South African coastal regions, which is a renowned tourist destination and home to 11.1 million people (Statistics South Africa 2015 Statistics South Africa. 2015. Mid-Year Population Estimates. Statistical release P0302. Pretoria, South Africa: Statistics South Africa. [Google Scholar]). This paper considers the state of coastal management, as well as implementation challenges being experienced at a local governance level, and highlights ways to address these. Data were acquired through questionnaire surveys and semistructured interviews. The Drivers-Pressures-State-Impact-Response (DPSIR) framework was used to identify relevant ICM issues and concerns and develop potential actions for improving the implementation of coastal management activities and the ICM Act. In the assessment of the ICM governance and implementation to date, a key concern identified was a general lack of coastal management knowledge among officials. It was specifically identified that knowledgeable management and capacity-building required championing from the provincial government in order to more efficiently and effectively implement the objectives of the ICM Act through an improved understanding of the coastal environment, its functioning and management.