Analisis Metode Pelaksanaan Plat Precast Dengan Plat Konvensional Ditinjau Dari Waktu Dan Biaya (Studi Kasus : Markas Komando Daerah Militer Manado)

Pemilihan metode pelaksanaan suatu proyek konstruksi sangat penting karena metode pelaksanaan yang tepat dapat memberikan hasil yang maksimal terutama jika ditinjau dari segi biaya maupun waktu. Salah satu USAha yang dilakukan oleh pengelola proyek adalah mengganti cara –cara konvensional menjadi lebih modern, yaitu dengan cara penerapan beton pracetak. Tujuan penelitian ini : (1) membandingkan metode pelaksanaan pembangunan antara penggunaan sistem beton konvensional. (2) Menganalisa biaya yang diperlukan pada kedua sistem tersebut dengan perhitungan Rab. (3) Menganalisa pengaruh waktu pelaksanaan antara sistem konvensional dan Precast terhadap biaya dengan Kurva S dari kedua sistem tersebut. Dari hal-hal tersebut akan diketahui sistem pengecoran mana yang efisien dari segi waktu, biaya, peralatan, maupun faktor pendukung, serta membandingkan antara precast fabrikasi dengan precast cast in situ. Beberapa aspek tentunya berbeda, baik untuk waktu, alat maupun proses yang akan dilakukan. Hasil penelitian memperlihatkan bahwa : dengan menggunakan metode precast membutuhkan waktu pelaksanaan selama 198 hari dengan Total biaya langsungnya adalah Rp 30,352,740,000,00, sedang untuk metode konvensional membutuhkan waktu pelaksanaan selama 226 hari dengan total biaya langsung Rp 30,230,145,000,00. Perbandingan biaya adalah Rp 122,595,000,00 sedang perbandingan waktu adalah 28 hari. Dapat disimpulkan bahwa pekerjaan menggunakan sistem precast membutuhkan biaya yang lebih besar dibandingkan sistem konvensional akan tetapi dengan waktu pengerjaan yang lebih singkat. Semakin besar volume pekerjaan dengan menggunakan sistem precast, semakin murah pula harganya dibandingkan dengan metode konvensional dan waktu pelaksanaannya juga lebih cepat, apalagi dengan menggunakan sistem Precast cast in situ

Hydroclimatic changes in the British Isles through the Last-Glacial-Interglacial Transition:Multiproxy reconstructions from the Vale of Pickering, NE England

European paleoenvironmental records through the Last Glacial-Interglacial Transition (LGIT; ca 16-8 cal ka BP) record a series of climatic events occurring over decadal to multi-centennial timescales. Changes in components of the climatic system other than temperature (e.g. hydrology) through the LGIT are relatively poorly understood however, and further records of hydroclimatic changes are required in order to develop a more complete understanding on the phasing of environmental and anthropogenic responses in Europe to abrupt climate change. Here, we present a multiproxy palaeoenvironmental record (macroscale and microscale sedimentology, macrofossils, and carbonate stable isotopes) from a palaeolake sequence in the Vale of Pickering (VoP), NE England, which enables the reconstruction of hydroclimatic changes constrained by a radiocarbon-based chronology. Relative lake-level changes in the VoP occurred in close association (although not necessarily in phase) to threshold shifts across abrupt climate change transitions, most notably lowering during cooling intervals of the LGIT (∼GI-1d, ∼GI-1b, and ∼GS-1). This reflects more arid hydroclimates associated with these cooling episodes in the British Isles. Comparisons to hydrological records elsewhere in Europe show a latitudinal bifurcation, with Northern Europe (50–60°N) becoming more arid (humid), and Southern Europe (40–50°N) becoming more humid (arid) in response to these cooling (warming) intervals. We attribute these bifurcating signals to the relative positions of the Atlantic storm tracks, sea-ice margin, and North Atlantic Polar Front (NAPF) during the climatic events of the LGIT

Positioning the Arts in the Research Process: Perspectives from Higher Education

Research in the visual arts has contributed to the creation of environments that involve cross-disciplinary, multidisciplinary and interdisciplinary or transdisciplinary projects in departments within and across universities. An overview is provided of the historical context of doctoral awards in the arts with a definition of the terms practice-based, practice-led, and practice as research discussed. It articulates the challenges when acquiring explicit and exact knowledge alongside more subjective approaches that utilize tacit knowledge from artistic practice in research projects. Drawing on examples from art practice and doctoral students work, it analyzes objective, subjective, empirical, and hermeneutic paradigms, as described by Pierre Bourdieu, which can combine empirical approaches and individual understandings to re-enforce our understandings of the world

The under reporting of recruitment strategies in research with children with life threatening illnesses: A systematic review

BACKGROUND: Researchers report difficulties in conducting research with children and young people (CYP) with life-limiting conditions (LLC) or life-threatening illnesses (LTI) and their families. Recruitment is challenged by barriers including ethical, logistical and clinical considerations. AIM: To explore how children and young people (aged 0-25 years) with life-limiting conditions or life-threatening illnesses and their families were identified, invited and consented to research published in the last 5 years. DESIGN: Systematic review. DATA SOURCES: Medline, PsycINFO, Web of Science, Sciences Citation Index, SCOPUS were searched for original English language research published between 2009-2014, recruiting children and young people with life-limiting conditions or life-threatening illness and their families. RESULTS: Two-hundred and fifteen studies; 152 qualitative, 54 quantitative, 9 mixed methods were included. Limited recruitment information but a range of strategies and difficulties were provided. The proportion of eligible participants from those screened could not be calculated in 80% of studies. Recruitment rates could not be calculated in 77%. Thirty-one per cent of studies recruited less than 50% of eligible participants. Reasons given for non-invitation included missing clinical or contact data, or clinician judgements of participant unsuitability. Reasons for non-participation included lack of interest and participants’ perceptions of potential burdens. CONCLUSIONS: All stages of recruitment were under reported. Transparency in reporting of participant identification, invitation and consent is needed to enable researchers to understand research implications, bias risk and to whom results apply. Research is needed to explore why consenting participants decide to take part or not and their experiences of research recruitment

Elevating zero dimensional global scaling predictions to self-consistent theory-based simulations

We have developed an innovative workflow, STEP-0D, within the OMFIT integrated modelling framework. Through systematic validation against the International Tokamak Physics Activity (ITPA) global H-mode confinement database, we demonstrated that STEP-0D, on average, predicts the energy confinement time with a mean relative error (MRE) of less than 19%. Moreover, this workflow showed promising potential in predicting plasmas for proposed fusion reactors such as ARC, EU-DEMO, and CFETR, indicating moderate H-factors between 0.9 and 1.2. STEP-0D allows theory-based prediction of tokamak scenarios, beginning with zero-dimensional (0D) quantities. The workflow initiates with the PRO-create module, generating physically consistent plasma profiles and equilibrium using the same 0D quantities as the IPB98(y,2) confinement scaling. This sets the starting point for the STEP (Stability, Transport, Equilibrium, and Pedestal) module, which further iterates between theory-based physics models of equilibrium, core transport, and pedestal to yield a self-consistent solution. Given these attributes, STEP-0D not only improves the accuracy of predicting plasma performance but also provides a path towards a novel fusion power plant (FPP) design workflow. When integrated with engineering and costing models within an optimization, this new approach could eliminate the iterative reconciliation between plasma models of varying fidelity. This potential for a more efficient design process underpins STEP-0D's significant contribution to future fusion power plant development.Comment: 12 pages, 13 figures, accepted by Physics of Plasmas 202

Middle and Late Pleistocene environmental history of the Marsworth area, south-central England

To elucidate the Middle and Late Pleistocene environmental history of south-central England, we report the stratigraphy, sedimentology, palaeoecology and geochronology of some deposits near the foot of the Chiltern Hills scarp at Marsworth, Buckinghamshire. The Marsworth site is important because its sedimentary sequences contain a rich record of warm stages and cold stages, and it lies close to the Anglian glacial limit. Critical to its history are the origin and age of a brown pebbly silty clay (diamicton) previously interpreted as weathered till. The deposits described infill a river channel incised into chalk bedrock. They comprise clayey, silty and gravelly sediments, many containing locally derived chalk and some with molluscan, ostracod and vertebrate remains. Most of the deposits are readily attributed to periglacial and fluvial processes, and some are dated by optically stimulated luminescence to Marine Isotope Stage (MIS) 6. Although our sedimentological data do not discriminate between a glacial or periglacial interpretation of the diamicton, amino-acid dating of three molluscan taxa from beneath it indicates that it is younger than MIS 9 and older than MIS 5e. This makes a glacial interpretation unlikely, and we interpret the diamicton as a periglacial slope deposit. The Pleistocene history reconstructed for Marsworth identifies four key elements: (1) Anglian glaciation during MIS 12 closely approached Marsworth, introducing far-travelled pebbles such as Rhaxella chert and possibly some fine sand minerals into the area. (2) Interglacial environments inferred from fluvial sediments during MIS 7 varied from fully interglacial conditions during sub-stages 7e and 7c, cool temperate conditions during sub-stage 7b or 7a, temperate conditions similar to those today in central England towards the end of the interglacial, and cool temperate conditions during sub-stage 7a. (3) Periglacial activity during MIS 6 involved thermal contraction cracking, permafrost development, fracturing of chalk bedrock, fluvial activity, slopewash, mass movement and deposition of loess and coversand. (4) Fully interglacial conditions during sub-stage 5e led to renewed fluvial activity, soil formation and acidic weathering

An Overview of the 13:8 Mean Motion Resonance between Venus and Earth

It is known since the seminal study of Laskar (1989) that the inner planetary system is chaotic with respect to its orbits and even escapes are not impossible, although in time scales of billions of years. The aim of this investigation is to locate the orbits of Venus and Earth in phase space, respectively to see how close their orbits are to chaotic motion which would lead to unstable orbits for the inner planets on much shorter time scales. Therefore we did numerical experiments in different dynamical models with different initial conditions -- on one hand the couple Venus-Earth was set close to different mean motion resonances (MMR), and on the other hand Venus' orbital eccentricity (or inclination) was set to values as large as e = 0.36 (i = 40deg). The couple Venus-Earth is almost exactly in the 13:8 mean motion resonance. The stronger acting 8:5 MMR inside, and the 5:3 MMR outside the 13:8 resonance are within a small shift in the Earth's semimajor axis (only 1.5 percent). Especially Mercury is strongly affected by relatively small changes in eccentricity and/or inclination of Venus in these resonances. Even escapes for the innermost planet are possible which may happen quite rapidly.Comment: 14 pages, 11 figures, submitted to CMD

The resilience of postglacial hunter-gatherers to abrupt climate change

Understanding the resilience of early societies to climate change is an essential part of exploring the environmental sensitivity of human populations. There is significant interest in the role of abrupt climate events as a driver of early Holocene human activity, but there are very few well-dated records directly compared with local climate archives. Here, we present evidence from the internationally important Mesolithic site of Star Carr showing occupation during the early Holocene, which is directly compared with a high-resolution palaeoclimate record from neighbouring lake beds. We show that-once established-there was intensive human activity at the site for several hundred years when the community was subject to multiple, severe, abrupt climate events that impacted air temperatures, the landscape and the ecosystem of the region. However, these results show that occupation and activity at the site persisted regardless of the environmental stresses experienced by this society. The Star Carr population displayed a high level of resilience to climate change, suggesting that postglacial populations were not necessarily held hostage to the flickering switch of climate change. Instead, we show that local, intrinsic changes in the wetland environment were more significant in determining human activity than the large-scale abrupt early Holocene climate events