Maximising revenue for non-firm distributed wind generation with energy storage in an active management scheme

The connection of high penetrations of renewable generation such as wind to distribution networks requires new active management techniques. Curtailing distributed generation during periods of network congestion allows for a higher penetration of distributed wind to connect, however, it reduces the potential revenue from these wind turbines. Energy storage can be used to alleviate this and the store can also be used to carry out other tasks such as trading on an electricity spot market, a mode of operation known as arbitrage. The combination of available revenue streams is crucial in the financial viability of energy storage. This study presents a heuristic algorithm for the optimisation of revenue generated by an energy storage unit working with two revenue streams: generation-curtailment reduction and arbitrage. The algorithm is used to demonstrate the ability of storage to generate revenue and to reduce generation curtailment for two case study networks. Studies carried out include a single wind farm and multiple wind farms connected under a 'last-in-first-out' principle of access. The results clearly show that storage using both operating modes increases revenue over either mode individually. Moreover, energy storage is shown to be effective at reducing curtailment while increasing the utilisation of circuits linking the distribution and transmission networks. Finally, renewable subsidies are considered as a potential third revenue stream. It is interesting to note that under current market agreements such subsidies have the potential to perversely encourage the installation of inefficient storage technologies, because of increased losses facilitating greater "utilisation" of renewable generation

Assessing the cumulative environmental effects of marine renewable energy developments: establishing common ground

Assessing and managing the cumulative impacts of human activities on the environment remains a major challenge to sustainable development. This challenge is highlighted by the worldwide expansion of marine renewable energy developments (MREDs) in areas already subject to multiple activities and climate change. Cumulative effects assessments in theory provide decision makers with adequate information about how the environment will respond to the incremental effects of licensed activities and are a legal requirement in many nations. In practise, however, such assessments are beset by uncertainties resulting in substantial delays during the licensing process that reduce MRED investor confidence and limit progress towards meeting climate change targets. In light of these targets and ambitions to manage the marine environment sustainably, reducing the uncertainty surrounding MRED effects and cumulative effects assessment are timely and vital. This review investigates the origins and evolution of cumulative effects assessment to identify why the multitude of approaches and pertinent research have emerged, and discusses key considerations and challenges relevant to assessing the cumulative effects of MREDs and other activities on ecosystems. The review recommends a shift away from the current reliance on disparate environmental impact assessments and limited strategic environmental assessments, and a move towards establishing a common system of coordinated data and research relative to ecologically meaningful areas, focussed on the needs of decision makers tasked with protecting and conserving marine ecosystems and services

The Determination of Carbonic Oxide in Illuminating Gas By Iodine Pentoxide

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A Biological Rationale for Musical Scales

Scales are collections of tones that divide octaves into specific intervals used to create music. Since humans can distinguish about 240 different pitches over an octave in the mid-range of hearing [1], in principle a very large number of tone combinations could have been used for this purpose. Nonetheless, compositions in Western classical, folk and popular music as well as in many other musical traditions are based on a relatively small number of scales that typically comprise only five to seven tones [2]–[6]. Why humans employ only a few of the enormous number of possible tone combinations to create music is not known. Here we show that the component intervals of the most widely used scales throughout history and across cultures are those with the greatest overall spectral similarity to a harmonic series. These findings suggest that humans prefer tone combinations that reflect the spectral characteristics of conspecific vocalizations. The analysis also highlights the spectral similarity among the scales used by different cultures

Assessment of anatomical knowledge by practical examinations: the effect of question design on student performance

The objective structural practical examination (OSPE) is a timed examination that assesses topographical and/or applied knowledge of anatomy with the use of cadaveric resources and medical images. This study investigated whether elements of question design (provision of clinical context, type of visual resources used, gender context, and difficulty) of an anatomy question affected students' performance and also whether there was any effect of basic demography or participation in various voluntary activities. Study participants were second-year medical students (n = 150), 83 of whom consented to fill in a questionnaire collecting demographics, revision preferences, and assessment preferences. The examination scores were matched with students' responses collected on the questionnaire and all data analyzed by multiple linear regression. Difficulty of the question was the only design element found to be significantly associated with the number of students that answered correctly (P = 0.001); clinical context, visual resources used and gender of the question were not significant. When individual students' marks were analyzed along with the questionnaire data, only the students' interest in participating in department's demonstrator program was a significant predictor of a high individual score, gender of the students showed a strong trend toward significance, with female students scoring on average higher than male students. The two part OSPE questions were dissociated and analyzed using binary logistic regression to determine whether a correct answer to Part 1 (identification of a tagged or pinned anatomical structures on a specimen or medical image) was predictive of a correct answer to Part 2 (assessment of the relevant functional, applied, or clinical knowledge), but no association was found. Anat Sci Educ. © 2016 American Association of Anatomists

The Villanova University School of Law (A History)

A History of the founding and major events and milestones of the Villanova University School of Law, published in 1991.https://digitalcommons.law.villanova.edu/books/1000/thumbnail.jp