Developing the New Zealand Soundmap: An exploration of soundmap practice, site listening, locative media and the sound environment

This text is an exegesis written in accompaniment to the development of the New Zealand Soundmap. The origin and development of soundmap practice and the emergence and development of related environmental sound practices are detailed. The exegesis concludes with an exposition of the development of the New Zealand Soundmap itself. Soundmap practice emerged from the sonic explorations of the World Soundscape Project, who coming out of Simon Fraser University of Burnaby, British Columbia, Canada, pioneered the first soundmaps in the early 1970’s. From its origins soundmap practice has spread and developed into its current form as a new media practice. This thesis deals with the development of a regional web-based soundmap for New Zealand. Various discursive strains from media studies, sonic arts, and phenomenological philosophy are woven together to explain the impetus, and value of soundmap practice and related environmental sound practices such as soundwalks and site-listening. The thesis ends with a critical analysis of successes and failures of the project towards its stated goal: to facilitate awareness of an engagement with the local sound environment

Experimental analysis of small masonry panels subject to long duration blast loading

Much research has been conducted towards short duration blast loading and its interaction with structures. The positive phase duration, t+, of a typical short duration high explosive blast is often below t+= 100ms. For the purposes of this research, long duration blast is considered to be an explosive event in which t+>100ms. This type of blast load offers added complexity when dealing with its interaction with structures due to the high impulses, drag winds and associated dynamic pressures. As part of an extended research study to develop a set of predictive algorithms, this paper investigates the breakage patterns and debris distribution of masonry panels subject to long duration blast loads. Experimental trials were conducted using the Air Blast Tunnel at MoD Shoeburyness, a specialised facility for long duration blast, in which two masonry panels were tested. The trials displayed varying degrees of breakage followed by a substantial debris distribution in both cases

Experimental analysis of debris distribution of masonry panels subjected to long duration blast loading

Blast loading of structures is a complex system dependent on a vast number of parameters from both the structure and blast wave. Even for the simplest of structures, small changes to its size and shape can have a large effect on the result when subjected to blast; additionally, small changes to the pressure or duration of the blast wave can drastically alter its interaction with a specific structure. This paper, as part of a larger in-depth research study, investigates the breakage patterns and debris distribution of masonry panels subjected to blast loads with a positive phase duration typically exceeding 100 ms. Three experimental trials were conducted, in which ten masonry panels of varying geometries were subjected to blast loads with peak static overpressures of approximately 55 kPa and 110 kPa, with corresponding positive phase durations of 200 ms and 150 ms respectively. All structures underwent total structural failure, followed by significant debris distribution with the results showing structural geometry, blast overpressure and impulse to be the key parameters responsible for the breakage pattern, initial fragmentation and debris distribution respectively

Expanded approaches to ecological sound practice : beyond the schaferean impasse

Expanded Approaches to Ecological Sound Practice: Beyond The Schaferean Impasse is a critical intervention into the domain of ecological sound practice that seeks to create pathways forward for the field beyond the romanticism and essentialism that it inherited from its founder R. Murray Schafer and his colleagues at the World Soundscape Project. This intervention is enacted through a critical relistening and rereading of the canonical works of the field, which are recontextualised through a number of nested frameworks drawn from the environmental humanities, media theory, and geography. These discussions are situated alongside case studies of contemporary sound works that are seen to be demonstrative of potential pathways forward for the field. The project poses a rethinking of ecological sound practice as an ethico-aesthetic practice that sees the artist/audience as playing a co-poietic role in the construction of the soundscape through ongoing processes of mediation. Within the context of this revised model for ecological sound practice, emphasis is given to understanding the ecological crisis, and the acts of listening and recording, in socially differentiated and situated terms, rather than in the anti-modernist and romantic terms of Schafer and company

Multilayer Dielectric Transmissive Optical Phase Modulator

A multilayer dielectric device has been fabricated as a prototype of a low-loss, low-distortion, transmissive optical phase modulator that would provide as much as a full cycle of phase change for all frequency components of a transmitted optical pulse over a frequency band as wide as 6.3 THz. Arrays of devices like this one could be an alternative to the arrays of mechanically actuated phase-control optics (adaptive optics) that have heretofore been used to correct for wave-front distortions in highly precise optical systems. Potential applications for these high-speed wave-front-control arrays of devices include agile beam steering, optical communications, optical metrology, optical tracking and targeting, directional optical ranging, and interferometric astronomy. The device concept is based on the same principle as that of band-pass interference filters made of multiple dielectric layers with fractional-wavelength thicknesses, except that here there is an additional focus on obtaining the desired spectral phase profile in addition to the device s spectral transmission profile. The device includes a GaAs substrate, on which there is deposited a stack of GaAs layers alternating with AlAs layers, amounting to a total of 91 layers. The design thicknesses of the layers range from 10 nm to greater than 1 micrometer. The number of layers and the thickness of each layer were chosen in a computational optimization process in which the wavelength dependences of the indices of refraction of GaAs and AlAs were taken into account as the design was iterated to maximize the transmission and minimize the group-velocity dispersion for a wavelength band wide enough to include all significant spectral components of the pulsed optical signal to be phase modulated

Establishing a predictive method for blast induced masonry debris distribution using experimental and numerical methods

When subjected to blast loading, fragments ejected by concrete or masonry structures present a number of potential hazards. Airborne fragments pose a high risk of injury and secondary damage, with the resulting debris field causing major obstructions. The capability to predict the spatial distribution of debris of any structure as a function of parameterised blast loads will offer vital assistance to both emergency response and search and rescue operations and aid improvement of preventative measures. This paper proposes a new method to predict the debris distribution produced by masonry structures which are impacted by blast. It is proposed that describing structural geometry as an array of simple modular panels, the overall debris distribution can be predicted based on the distribution of each individual panel. Two experimental trials using 41 kg TNT equivalent charges, which subjected a total of nine small masonry structures to blast loading, were used to benchmark a computational modelling routine using the Applied Element Method (AEM). The computational spatial distribution presented good agreement with the experimental trials, closely matching breakage patterns, initial fragmentation and ground impact fragmentation. The collapse mechanisms were unpredictable due to the relatively low transmitted impulse; however, the debris distributions produced by AEM models with matching collapse mechanisms showed good agreement with the experimental trials

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The U.S. Navy's new multiprocessor, the AN/UYS-2 Enhanced Modular Signal Processor (EMSP) utilizes a First-Come-First-Serve (FCFS) algorithm to transfer data. This algorithm is simple to implement but provides no mechanism to control execution of a specific application on the AN/UYS-2 which prevents performance predictions. A Large Grain Data Flow (LGDF) representation of a specific application is utilized to predict performance, with the introduction of trigger queues (dependency arcs) into the graphs to control execution. I utilized the EMSP Common Operational Software (ECOS) Workstation to execute graph representations of specific applications used by the U.S. Navy in the Anti-Submarine Warfare (ASW) arena. A complete description of the ECOS workstation, and the process of transforming specific applications into graph representations to be executed on the ECOS Workstation is demonstrated. Specifically, the Correlator Graph which represents a real-time ASW process is examined. To control and improve performance, the technique of implementing trigger queues using the ECOS Workstation is demonstrated. A basic graph is executed and referenced as a benchmark, with two reconstructed graphs executed demonstrating how trigger queues effect graph execution. The node execution times statistics indicate trigger queues control execution and will provide a mechanism to predict node performance.http://archive.org/details/largegraindatflo1094530570NANAU.S. Navy (U.S.N.) author

Microresonator and associated method for producing and controlling photonic signals with a photonic bandgap delay apparatus

By applying a photonic signal to a microresonator that includes a photonic bandgap delay apparatus having a photonic band edge transmission resonance at the frequency of the photonic signal, the microresonator imparts a predetermined delay to the photonic signal. The photonic bandgap delay apparatus also preferably has a photonic band edge transmission resonance bandwidth which is at least as wide as the bandwidth of the photonic signal such that a uniform delay is imparted over the entire bandwidth of the photonic signal. The microresonator also includes a microresonator cavity, typically defined by a pair of switchable mirrors, within which the photonic bandgap delay apparatus is disposed. By requiring the photonic signal to oscillate within the microresonator cavity so as to pass through the photonic bandgap delay apparatus several times, the microresonator can controllably impart an adjustable delay to the photonic signal