The Chanka: Archaeological Research in Andahuaylas (Apurimac), Peru

In AD 1438 a battle took place outside the city of Cuzco that changed the course of South American history. The Chanka, a powerful ethnic group from the Andahuaylas region, had begun an aggressive program of expansion. Conquering a host of smaller polities, their army had advanced well inside the territory of their traditional rival, the Inca. In a series of unusual maneuvers, the Inca defeated the invading Chanka forces and became the most powerful people in the Andes. Many scholars believe that the defeat of the Chanka represents a defining moment in the history of South America as the Inca then continued to expand and establish the largest empire of the Americas. Despite its critical position in South American history, until recently the Chanka heartland remained unexplored and the cultural processes that led to their rapid development and subsequent defeat by the Inca had not been investigated. From 2001 to 2004, Brian Bauer conducted an archaeological survey of the Andahuaylas region. This project represents an unparalleled opportunity to examine theoretical issues concerning the history and cultural development of late-prehistoric societies in this area of the Andes. The resulting book includes an archaeological analysis on the development of the Chanka and examines their ultimate defeat by the Inca. Series: Monographs 6

Energetically efficient behaviour may be common in biology, but it is not universal: a test of selective tidal stream transport in a poor swimmer

Selective tidal stream transport (STST) is a common migration strategy for a wide range of aquatic animals, facilitating energetically efficient transport, especially of species considered poor swimmers. We tested whether this mechanism applies during the upstream migration of a poor swimmer, the European river lamprey Lampetra fluviatilis, in a macrotidal estuary. Lamprey (n = 59) were acoustically tagged and tracked in a 40 km section of the River Ouse estuary (NE England) in autumn 2015. Against expectations, lamprey did not use STST and migrated upstream during flood, ebb and slack tide periods. Lamprey also migrated during both day and night in most of the study area, probably due to the high turbidity. The global migration speed (all individuals, over the entire track per individual) was (mean ± SD) 0.15 ± 0.07 m s-1. The migration speed varied significantly between tidal periods (0.38 ± 0.04 m s-1 during flooding tides, 0.12 ± 0.01 m s-1 during ebbing tides and 0.28 ± 0.01 m s-1 during slacks). It was also higher in areas not affected by tides during periods of high freshwater discharge (0.23 ± 0.08 m s-1) than in affected areas (0.17 ± 0.14 m s-1). If the energetic advantages of STST are not employed in macrotidal environments, it is likely that the fitness costs of that behaviour exceed potential energy savings, for example due to increased duration of exposure to predation. In conclusion, STST is evidently not universal in relatively poor swimmers; its use can vary between species and may vary under different conditions

Locally linear embedding-based prediction for 3D holoscopic image coding using HEVC

Holoscopic imaging is a prospective acquisition and display solution for providing true 3D content and fatigue-free 3D visualization. However, efficient coding schemes for this particular type of content are needed to enable proper storage and delivery of the large amount of data involved in these systems. Therefore, this paper proposes an alternative HEVC-based coding scheme for efficient representation of holoscopic images. In this scheme, some directional intra prediction modes of the HEVC are replaced by a more efficient prediction framework based on locally linear embedding techniques. Experimental results show the advantage of the proposed prediction for 3D holoscopic image coding, compared to the reference HEVC standard as well as previously presented approaches in this field.info:eu-repo/semantics/submittedVersio

Session C7: Tricky Little Lampreys! Efficacy of an Unmodified and Modified Super-Active Baffle Fish Pass for European River Lamprey (Lampetra Fluviatilis)

Abstract: Achieving good upstream passage of lampreys, a threatened group of serpentine fishes, remains a problem. The ability of European river lamprey (Lampetra fluviatilis) to pass a Crump weir using a 15% gradient Larinier superactive baffle fish pass during their upstream spawning migration was tested. This type of fish pass has become widespread in Europe in the last two decades, but its efficiency for river lamprey is unknown. River lamprey were PIT tagged (n=350) PIT, a subsample were acoustic tagged (n=31), and all were released downstream in batches in Oct-Dec 2013. Telemetry arrays were installed in the pass (PIT) and river (acoustic) and ran throughout the migration period. Attraction efficiency into the fishway (estimated at 90.1%) was good and half of lampreys entered within 24 h of release, but only one lamprey successfully ascended the pass (0.3% passage efficiency), despite many entering repeatedly. Out of 29 acoustic tagged lamprey that visited the weir, four (13.8%) passed the weir directly. The fishway was unsuitable for river lamprey over a wide range of flows. The pass was modified by addition of vertically mounted peg-and-slot tiles, interrogated at the entrance and exit by PIT telemetry and retested in winter 2014- 15. There was an increase in passage success. Preliminarily, out of 197 river lamprey PIT tagged Oct-Dec 2014, 184 (93.4%) were logged at the fishway entrance. 74 (40.2%) entered the tiles at the downstream end, of which 14 (18.9%) swam up through the tiles successfully. Twelve lamprey (6.5% passage efficiency) were logged at the upstream exit of the pass. Reduced flow velocity in combination with increased availability of resting habitat within the tiles may increase the passage efficiency of this type of fish pass for river lamprey. Although increased, passage efficiency, after placement of the tiles, is still considered far from optimal

Light field HEVC-based image coding using locally linear embedding and self-similarity compensated prediction

Light field imaging is a promising new technology that allows the user not only to change the focus and perspective after taking a picture, as well as to generate 3D content, among other applications. However, light field images are characterized by large amounts of data and there is a lack of coding tools to efficiently encode this type of content. Therefore, this paper proposes the addition of two new prediction tools to the HEVC framework, to improve its coding efficiency. The first tool is based on the local linear embedding-based prediction and the second one is based on the self-similarity compensated prediction. Experimental results show improvements over JPEG and HEVC in terms of average bitrate savings of 71.44% and 31.87%, and average PSNR gains of 4.73dB and 0.89dB, respectively.info:eu-repo/semantics/acceptedVersio

Contact Failure Identification in Multilayered Media via Artificial Neural Networks and Autoencoders

The estimation of defects positioning occurring in the interface between different materials is performed by using an artificial neural network modeled as an inverse heat conduction problem. Identifying contact failures in the bonding process of different materials is crucial in many engineering applications, ranging from manufacturing, preventive inspection and even failure diagnosis. This can be modeled as an inverse heat conduction problem in multilayered media, where thermography temperature measurements from an exposed surface of the media are available. This work solves this inverse problem with an artificial neural network that receives these experimental data as input and outputs the thermalphysical properties of the adhesive layer, where defects can occur. An autoencoder is used to reduce the dimension of the transient 1D thermography data, where its latent space represents the experimental data in a lower dimension, then these reduced data are used as input to a fully connected multilayer perceptron network. Results indicate that this is a promising approach due to the good accuracy and low computational cost observed. In addition, by including different noise levels within a defined range in the training process, the network can generalize the experimental data input and estimate the positioning of defects with similar quality.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Finance Code 001), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Grant CAPES/PrInt No. 88887.469279/2019-00PID2020-112754 GB-I00 (Spanish Ministry of Economy and Competitiveness and funds from the European Regional Developement Fund, ERDF)B-TIC-640-UGR20 (Regional Govern of Andalusia, Spain