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In response to Timothy Darvill's article, ‘Mythical rings?’ (this issue), which argues for an alternative interpretation of Waun Mawn circle and its relationship with Stonehenge, Parker Pearson and colleagues report new evidence from the Welsh site and elaborate on aspects of their original argument. The discovery of a hearth at the centre of the circle, as well as further features around its circumference, reinforces the authors’ original interpretation. The authors explore the evidence for the construction sequence, which was abandoned before the completion of the monument. Contesting Darvill's argument that the Aubrey Holes at Stonehenge originally held posts, the authors reassert their interpretation of this circle of cut features as Bluestone settings.

Recent environmental studies and policies have recommended maintaining archaeological landscape features such as intercropping, agroforestry and cross-slope barriers (e.g. hedgerows, stone walls, earth banks) for their potential benefits to ecosystems. This study focuses on a portion of the Tuscan-Emilian Apennines coinciding with the municipality of Vetto d'Enza (commonly referred as Vetto), located on the right bank of the Enza River in the Man and the Biosphere UNESCO reserve (Emilia-Romagna region, Northern Italy). The main characteristics of this historic rural landscape trace their origin back to the Middle Ages at the period of the Great Countess Matilda of Canossa (10-11th century CE) and the area’s land management system appears to have remained largely unaltered until the end of the 19th-century CE. Among the most distinctive characteristics of this historic landscape are relicts of agroforestry practices (known as ‘alberata emiliana’) and well-preserved stone walls and earth banks that have been used extensively between steeply-sloping fields to delimit tenurial boundaries and to face agricultural terraces. Optically stimulated luminescence profiling and dating (OSL-PD) has been applied to date the sediments associated with earth banks, stone walls and agricultural terraces. The results provide secure construction dates during the Medieval Climate Anomaly - (MCA). This period (ca. 900–1350 CE) is arguably one of the most crucial moments of recent climate change that impacted societies, particularly in Europe. Above average temperatures allowed high-elevation settlements to persist throughout the MCA, though social trends played a large role in the conversion of uplands into an agro-pastoral landscape. These processes are particularly evident on the Apennine mountains, where mediaeval deforestation coincided with intensification of agriculture associated with development of monastic estates that exploited increasingly larger land holdings as well as new settlement patterns in higher-elevation defensible locations.

Ruddons Point, on the Firth of Forth coastline, Scotland, is a laterally extensive terrace of glacial and marine sediment deposits raised above current sea-level, situated near to Kincraig Point, a key site that records a series of stepped erosional platforms carved into the local bedrock, interpreted as post Last Glacial Maximum palaeoshorelines. The deposits at Ruddons Point continue inland, with exposures of the raised sands and gravels cut by the local river, the Cocklemill Burn. The site provides an opportunity to examine the depositional history through the Late Devensian and Holocene. Geophysical survey aided in interpreting characteristics of subsurface sediments such as the transition between the younger saltmarsh sediments and older underlying sands and clays below, which slope in a northerly direction. A chronology obtained through optically stimulated luminescence (OSL) dating spans from c. 29 ka for sands and clays at an elevation of −0.66 mOD to surface windblown sands at c. 9.2 ka, formed prior to the Main Postglacial Transgression. Dating of inland raised marine deposits along the Cocklemill Burn records dates ranging from c. 8.9 to c. 4.3 ka. The raised marine deposits of Ruddons Point range from c. 8.1 to c. 2.9 ka, deposited unconformably on glacial tills and clays. This multidisciplinary field study builds depositional scenarios utilizing two dating methods, spanning the last c. 29 ka, to better understand coastal evolution for a region which has experienced complex relative sea-level variations. Supplementary material : Supplementary data related to this research article is available at https://doi.org/10.6084/m9.figshare.c.6080999 Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/topic/collections/early-career-research

Agricultural terraces, which demonstrate an ingenious and sustainable way of transforming hilly slopes into arable land, are widespread in Mediterranean landscapes, stretching from southern Portugal to the Judean Highlands. Despite their ecological and heritage values, there remain significant temporal and spatial gaps in understanding their histories, how they were constructed and what their socio-economic implications were for early populations. This lack of knowledge further restricts understanding the effects of terracing on landscape in terms of mitigating the impacts of past climate change and informing sustainable strategies for the future of land-management. To this end, we employed a multidisciplinary approach to a case study in Naxos, Greece. A GIS-based technique which uses a range of cartographic remote sensing data was employed to identify over 20 terrace sites, and trenches were hand-dug and placed in a relative chronological sequence using a portable optically stimulated luminescence (OSL) dating reader and gamma spectrometer. Samples were then collected for absolute OSL dating, micromorphology and x-ray fluorescence (XRF) analyses. Trench profiles were documented using high-resolution image-based modelling for accurate sample location and volumetric reconstruction of soil layers, and historic and modern aerial spaceborne data were used together with sample results to create models of terrace systems for spatiotemporal analyses. The results of this multidisciplinary approach adopted here have produced evidence of large-scale land-use in periods for which no other evidence indicative of landscape exploitation survives. A chronological framework based on over 25 OSL ages suggests terrace construction in Naxos between ~400 BC and the 16th century AD with intensification during the Medieval Greek period. Applications of soil micromorphology and XRF analyses identify key evidence of natural soil development and past land use including irrigation, soil mixing, crop residues and anthropogenic fertilisers. Modelling of terrace system development indicate their value as long-term resilient, adaptable agricultural and environmental features: where terrace systems have been maintained, reused, or abandoned under vegetation landscapes appear to maintain greater stability, retaining valuable soils and habitats compared to areas where terrace systems have been affected by overgrazing or consolidated by mechanical means. We conclude that our multidisciplinary approach has concomitant implications for the future sustainability and biodiversity of Mediterranean landscapes and beyond.

For the normal working of the electrical apparatus customers want an uninterrupted flow of sinusoidal voltage and current of continual magnitude and frequency at the AC mains. Although the generated voltage at power plants is almost sinusoidal but our current power system has wide range of electrical apparatus some of which are non-linear in nature which causes complications in the power supply. Also, few other unavoidable conditions like lightning strike and faults also induces power quality complications. Various FACTS devices are utilized to eliminate any power quality concerns in current and voltage signals. One of these numerous devices is the unified power quality conditioner (UPQC), and this paper provides a literature overview on the subject.

Linear dunes are the most widespread dune type worldwide and act as important geoproxies of late Quaternary environmental change in deserts. They are less common in the Thar Desert, India than other dune types, especially parabolic forms, and to date their development history is poorly understood. Here we investigate a linear dunefield in the northern Thar through analysis of a series of excavated full dune profile sites and the application of optically stimulated luminescence (OSL) dating to provide chronometric control. Results show that linear dunes have been present since at least ~58 ka and were active throughout much of the Holocene. The early Holocene, a period marked by strong Indian summer monsoon winds (e.g., Gill et al., 2017), has been shown as the last major phase of dune accumulation recorded in all sites, with ages ranging from ~11.6–8.6 ka. Two spatially restricted records of dune accumulation have also been identified during the later part of Holocene: ~4–3 ka and ~2–1 ka, attributed to localised reworking within the dunes. The suite of luminescence ages generated from the study region confirms the principle recognised in other dunefields (e.g., the south-western Kalahari; Stone and Thomas, 2008) and theoretically (Bailey and Thomas, 2014) that age records from individual dunes are unlikely to capture the developmental history of dunefields.

The Thar Desert dune system in north-west India and eastern Pakistan provides a rich archive of past environmental, geomorphological and climatic change. Much of the knowledge about the timing of dune accumulation in the Thar stems from scattered and sporadic records, based on older luminescence dating protocols. If the Thar dune record is to be incorporated within a growing multiproxy framework of past climate and environmental dynamics, it is necessary to generate a systematic record of the timing of dunefield accumulation. From this, relationships to climate and other drivers of dune activity may then be better established. To this end, an intensive programme of field sampling and optically stimulated luminescence (OSL) dating was carried out from a dunefield in the east-central Thar Desert. This study presents the first detailed Holocene dune accumulation history from the region, and sheds light on the development of the multi-generational parabolic dune systems. In contrast to previously published work, we identify the importance of the Holocene and the last millennium as periods with a number of preserved accumulation phases. OSL ages suggest that accumulation was persistent during the early and mid-Holocene (within 11.7-5.5 ka), late Holocene (2-1 ka), as well as two major phases in the last millennium (600 – 200 a and within the last 70 a). Potential drivers of dune mobility in the last century include a strong anthropogenic dimension. Rapid net accumulation is recorded in the last 70 years, with rates varying between 2 and 5 m/year, in an environment where agricultural pressures have increased dramatically with the advent of irrigation schemes expanding into dunefield areas. © 2019 John Wiley & Sons, Ltd.

Ruddons Point, situated on the Firth of Forth coastline, Scotland, is a laterally extensive terrace of glacial and marine sediment deposits which are raised above current sea level. The deposits are situated near to Kincraig Point, a key site that records a series of stepped erosional platforms carved into the local tuff and agglomerate bedrock, representing a series of post Last Glacial Maximum (LGM) paleoshorelines. The raised marine deposits of Ruddons Point are composed of sand, shell, gravel and cobble horizons, which have been deposited unconformably on glacial tills and clays. 1km inland, incised by a small stream (the Cocklemill Burn), numerous cut banks reveal further raised deposits. Previous attempts to date these sediments have produced conflicting depositional histories, with no clear correlation to the Kincraig Point paleoshorelines or those dated further west along the Forth Valley. To this end, a multidisciplinary study was conducted to provide a detailed geochronology and interpretation of this diverse field area, ranging from the dating of glacial clays, thought to be deposited during the early phases of sedimentation leading up to the LGM, through to establishing the timing of marine sediment deposition in the Mid to Late Holocene. Geophysical electrical surveys were employed to supplement the subsurface investigations of the shore and adjacent saltmarsh and to aid construction of a sedimentary deposition model. Optically stimulated luminescence dating and radiocarbon dating were carried out on selected samples through the raised deposits and subsurface cores to provide a chronometric framework. Results demonstrate that subsurface clay horizons date to ~29 ka, indicating deposition at the onset of the last glacial. Inland raised deposits along the Cocklemill Burn preserve periods of sedimentation ranging from ~8.5 ka to ~4.5ka, and suggest a punctuated rise in sea level during the Mid Holocene. The nearshore raised sands and gravels of Ruddons Point are dated to ~3.5ka, deposited during a period of relative sea level (RSL) fall in the Late Holocene. The study concludes that the combination of detailed fieldwork, geophysical survey and dating allow the scope for complex landscape changes to be identified and further the understanding of the interplay between glacial isostatic adjustment and RSL changes across the postglacial coastlines of Fife.

Metaheuristic algorithms, in the field of engineering, have attracted researchers for problem-solving of complex and non-linear optimization. Many algorithms have been designed to address wide-ranging applications such as GSA—gravitational search algorithms (GSA), PSO—particle swarm optimization, GWO—grey wolf optimization, and various hybrid plus evolutionary algorithms. Hybrid algorithms also made for such wide-range application, but the drawback of such algorithms are convergence time is very high and challenging to implement for multiple wide range applications. Cuckoo Search (CS) is an optimization technique, developed in 2009, is a highly efficient algorithm. It is an algorithm that is based on population and is also a nature-inspired metaheuristic algorithm, which is easy to implement for such applications. The success of the algorithm has been fueled because of its characteristics, i.e. its simplicity, few parameter, ease of implementation. Cuckoos are delightful birds, which have attracted people not only because of their melodious sound but also because of their aggressive reproduction capability. The algorithm addresses two important behavioral aspects of some cuckoos i.e. brood parasitism and levy flights. The two Ani and Guira cuckoo species will all lay eggs in a communal nest. The cuckoo can then remove the eggs laid by others to improve the probability of hatching the laid eggs. Cuckoo immigration along with environmental factors make the cuckoos to find an appropriate and also a place for reproduction and breeding. Cuckoos presents the random walk Levy flight behavior, which enables the algorithm to completely explore the search space. In CS algorithm fixed number of better fitness cuckoos survive in the environment. This chapter introduces with the mathematical concept of CS algorithm and summarizes different research articles where the algorithm has been explored in the field of engineering. Furthermore, the resent version of CS algorithm are addressed which mainly focuses on modified and hybrid versions. The novelty of this chapter is that it presents current trending research aspects of CS algorithm in the field of engineering, machine and deep learning. The chapter concludes with the future direction which can be investigated using CS algorithm in the field of science and technology.

This report concerns optically stimulated luminescence (OSL) investigations of a soil profile at Ulbjerg Klint, Central Jutland, Denmark. At this site, a minor landslide had exposed some unusually clear plough marks, which might contribute to the understanding of the first use of the mould-board plough in southern Scandinavia. The aims were first to date the plough marks, and secondly to date the oldest phase of the sedimentary archive of this site, with a remarkable thick sequence of aeolian sands with high potentiale for archaeological and paleo-climate studies. The report presents the OSL method, the results, a discussion and a conclusion, while the appendixes contains analytical description and a detailed soil profile and sampling description. Combined, the determined OSL ages reveal that over a 2500 years period the vegetation on this exposed coastal cliff was removed several times with episodes of drifting sand as a consequence. The first aeolian sand layer is dated at or slightly after 5th century BCE, i.e. around the transition between the Danish late Bronze Age to the pre-Roman Iron Age. The aeolian sand layer with the clear plough marks is from the 17th century CE, i.e. in the Little Ice Age. Due to the limited number of OSL dated samples, no additional climatic or land use indications could be established.

Managing and defining multiple tasks over different physical and digital workspaces are done by using various strategies.In this paper we put light on how computer based task management tools can support task management on a desktop or a smart phone and how it reacts in a fatal situation to the processes out of limit. The key concept in any of the operating system which allows the particular system to support multitasking system, etc. is Task Scheduling. It’s the core which refers to the basic way; different processes are allowed to share the common CPU. Scheduler and dispatcher are the software which helps to carry out this project.

The thought of shaping your ideas into reality has achieved its literal meaning. A future where we can hold a tangible product in our hand which was the part of our imagination minutes ago is around the corner. The 3D Model printing isalready an exciting and successful venture. Manufacturing a product which you saw on the shelf of a local store, a complicated industrial part, a small and precise component of an aircraft, or just a prototype that gives shapes to your idea. In printing system domains, they majorly use two technologies either using CAD software to make the digital files or to use a three-dimensional scanner to scan a 3D object to create a digital copy and to validate and implement the printed model. We are mainly having three techniques for 3D model creation like Selective Laser Sintering (SLS), Fused Deposition Modeling (FDM) and Stereo lithography (SLA). We present an illustrative study of the 3D printing techniques, working of 3D printer, their benefits and drawbacks, its impact on the economy.

Due to the scarcity of geochemical and palaeoecological proxies in drylands, dunes have often been used as geoproxies for late Quaternary palaeoenvironmental reconstruction, with chronologies commonly provided by luminescence dating. Owing to their widespread occurrence and location in a monsoonal regime, dunes in the Thar Desert in South Asia act as important archives of past landscape change. Previous reviews have assimilated dune age data from the Thar and suggested a temporally and spatially complex record of sediment accumulation over the last ∼70 ka. New luminescence age data presented in this study and from recent dunefield based investigations demonstrate a stronger Holocene record of dune building in parts of the Thar than previously suggested. In this study, the Accumulation Intensity (AI) methodology is applied to new and old data sets, providing records of dune accumulation that can be analysed alongside other palaeoenvironmental records. AI analysis demonstrates the significance of Holocene dune accumulation in the Thar landscape, with accumulation peaks observed between ∼12 and ∼8 ka, centred around ∼7, ∼5 and ∼3.5 ka, and in last two millennia. The strengthening of the Indian Summer Monsoon remains a significant influence on widespread dune accumulation in the early Holocene, but dunefields have also shown diverse and spatially intensive responses to sediment supply and anthropogenic disturbances during the late Holocene. Additionally, aeolian-fluvial sequences associated with the Ghaggar-Hakra palaeochannel along the northern margin of the Thar also display dynamic geomorphic behaviour during the Holocene. The integration and interpretation of the AI data with published, highly resolved geochemical proxies of palaeoclimate, shows a complex relationship between geoproxy and geochemical records. We suggest that process studies of geomorphologic systems and their diverse responses to the same environmental stimuli must be given due consideration before deriving palaeoenvironmental interpretations. Despite the presence of over a hundred Holocene dune records from the Thar, there still remains marked spatial and temporal gaps. Further intensive investigations of distinct dunefields with a strong chronometric framework and geomorphological grasp are required to gain significant insights into wider Thar landscape and palaeoenvironmental dynamics.

Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 890561, Historic Landscape and Soil Sustainability (HiLSS). Funding for fieldwork and analysis was provided through the TerraSAgE project (Terraces as Sustainable Agricultural Environments) from UKRI-Arts and Humanities Research Council (AHRC ref: AH/T000104/1). International policies and guidelines often highlight the divide between 'nature' and 'heritage' in landscape management, and the weakness of monodisciplinary approaches. This study argues that historic agricultural practices have played a key role in shaping today's landscapes, creating a heritage which affords opportunities for more sustainable landscape management. The paper develops a new interdisciplinary approach with particular reference to soil loss and degradation over the long term. It presents innovative methods for assessing and modelling how pre-industrial agricultural features can mitigate soil erosion risk in response to current environmental conditions. Landscape archaeology data presented through Historic Landscape Characterisation are integrated in a GIS-RUSLE model to illustrate the impact of varying historic land-uses on soil erosion. The resulting analyses could be used to inform strategies for sustainable land resource planning. Publisher PDF