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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

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.

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.