1,258 research outputs found
A Source-Critical Analysis of the Synoptic Resurrection Accounts
This thesis applies the Four-Source Hypothesis to the study of the resurrection accounts in the Synoptic Gospels. Scholars have addressed the Synoptic Problem in a variety of ways. Some have sought to harmonize the Gospels into one cohesive narrative, while others have concluded that the writings are contradictory and irreconcilable. Addressing the challenges associated with the Synoptic problem, this study evaluates the claims that each Gospel writer makes about the resurrection of Christ while assessing the unique characteristics and points of emphasis in each account. The resurrection narratives are used as a case study because of their importance to Christianity and their ability to illustrate some of the complexities that relate to the Synoptic Problem. Mark is presented as the first Gospel to be written, and the arguments for the majority view among scholars of Markan priority are surveyed. Markâs original resurrection account ends abruptly at Mark 16:8, causing Matthew and Luke to supplement their Markan source to complete their resurrection narratives. Matthew is presented as an expansion of Mark, combining it with Q and M to produce a compromise Gospel that brought together the competing branches within early Christianity. It is demonstrated that Matthew\u27s Galilee motif provides an explanation for why the resurrection appearance of Jesus occurs in Galilee with no mention of the other Jerusalem appearances. Luke is presented as the third Gospel, with knowledge of Mark, but often deferring to sources Q and L. It is suggested that Luke\u27s redemptive view of Jerusalem causes him to focus only on the Jerusalem appearances of Jesus while excluding the Galilee appearances. The study concludes with an evaluation of arguments against the Synoptic resurrection accounts and the implications of applying the findings from source criticism to the reading of the Synoptic resurrection accounts
Review: Marine natural products
This review covers the literature published in 2003 for marine natural products, with 619 citations (413 for the period January to December 2003) referring to compounds isolated from marine microorganisms and phytoplankton, green algae, brown algae, red algae, sponges, coelenterates, bryozoans, molluscs, tunicates and echinoderms. The emphasis is on new compounds (656 for 2003), together with their relevant biological activities, source organisms and country of origin. Biosynthetic studies or syntheses that lead to the revision of structures or stereochemistries have been included (78), including any ďŹrst total syntheses of a marine natural product
Open-source development experiences in scientific software: the HANDE quantum Monte Carlo project
The HANDE quantum Monte Carlo project offers accessible stochastic algorithms
for general use for scientists in the field of quantum chemistry. HANDE is an
ambitious and general high-performance code developed by a
geographically-dispersed team with a variety of backgrounds in computational
science. In the course of preparing a public, open-source release, we have
taken this opportunity to step back and look at what we have done and what we
hope to do in the future. We pay particular attention to development processes,
the approach taken to train students joining the project, and how a flat
hierarchical structure aids communicationComment: 6 pages. Submission to WSSSPE
Accurate exchange-correlation energies for the warm dense electron gas
Density matrix quantum Monte Carlo (DMQMC) is used to sample exact-on-average
-body density matrices for uniform electron gas systems of up to 10
matrix elements via a stochastic solution of the Bloch equation. The results of
these calculations resolve a current debate over the accuracy of the data used
to parametrize finite-temperature density functionals. Exchange-correlation
energies calculated using the real-space restricted path-integral formalism and
the -space configuration path-integral formalism disagree by up to
\% at certain reduced temperatures and densities . Our calculations confirm the accuracy of the configuration
path-integral Monte Carlo results available at high density and bridge the gap
to lower densities, providing trustworthy data in the regime typical of
planetary interiors and solids subject to laser irradiation. We demonstrate
that DMQMC can calculate free energies directly and present exact free energies
for and .Comment: Accepted version: added free energy data and restructured text. Now
includes supplementary materia
The sign problem and population dynamics in the full configuration interaction quantum Monte Carlo method
The recently proposed full configuration interaction quantum Monte Carlo
method allows access to essentially exact ground-state energies of systems of
interacting fermions substantially larger than previously tractable without
knowledge of the nodal structure of the ground-state wave function. We
investigate the nature of the sign problem in this method and how its severity
depends on the system studied. We explain how cancelation of the positive and
negative particles sampling the wave function ensures convergence to a
stochastic representation of the many-fermion ground state and accounts for the
characteristic population dynamics observed in simulations.Comment: 11 pages. 6 figure
Preconditioning and perturbative estimators in full configuration interaction quantum Monte Carlo
We propose the use of preconditioning in FCIQMC which, in combination with
perturbative estimators, greatly increases the efficiency of the algorithm. The
use of preconditioning allows a time step close to unity to be used (without
time-step errors), provided that multiple spawning attempts are made per
walker. We show that this approach substantially reduces statistical noise on
perturbative corrections to initiator error, which improve the accuracy of
FCIQMC but which can suffer from significant noise in the original scheme.
Therefore, the use of preconditioning and perturbatively-corrected estimators
in combination leads to a significantly more efficient algorithm. In addition,
a simpler approach to sampling variational and perturbative estimators in
FCIQMC is presented, which also allows the variance of the energy to be
calculated. These developments are investigated and applied to benzene
(30e,108o), an example where accurate treatment is not possible with the
original method.Comment: 15 pages, 7 figure
Surface integrity of additive manufacturing parts: a comparison between optical topography measuring techniques
Additive Manufacturing (AM) presents significant industry-specific advantages allowing the creation of complex geometries and internal features that cannot be produced using conventional manufacturing processes. However, a current limitation of AM is the degraded dimensional control and surface integrity of specific surfaces. The parts are constructed through layer-by-layer approach, each layer presenting a characteristic âfingerprintâ. The functional performance of the final part is influenced by the morphology of the outer surface as well as by the surface quality introduced at intermediate layers. Surface texture metrology therefore can play an enabling role in AM-related manufacture and research. The use of optical topography measurement instrumentation allows for a high level of detail in the acquisition of topographic information. Some of the most commonly used optical measuring instruments are Vertical Scanning Interferometry (CSI), Imaging Confocal Microscopy (CONF), and Focus Variation (FV), each one has benefits and drawbacks in terms of acquisition time and measurement resolution.
AM surfaces overall present complex topographical features, requiring the acquisition of large surface areas and large z-scans which considerably increases the acquisition time. Speed is a key factor in industrial practice, and time optimization is required for quality control and surface analysis before down-stream processes. This paper reports on the measurement and characterisation of the surface texture of metal powder bed fusion AM parts. All measurements were performed in the same SENSOFAR S-NEOX instrument using the commonly used optical technologies (CSI, CONF, and FV) and the latest step in confocal measurement technology called Continuous Confocal (C-CONF). The resolution and acquisition time of each technique is analysed in order to check the suitability of each method to characterize and describe the AM surface microstructures in a time-efficient way
Surface Characterisation Based Tool Wear Monitoring in Peripheral milling
The progress of surface metrology in the last decade has led to improved 3D characterisation of surfaces which offers the possibility of monitoring manufacturing operations to give highly detailed information regarding the machine tool condition. This paper presents a case study where areal surface characterisation is used to monitor tool wear in peripheral milling. Due to the fact that tool wear has a direct effect on the machined workpiece surface, the machined surface topography contains much information concerning the machining conditions including the tool wear state. Through analysing the often subtle changes in the surface topography the tool wear state can be highlighted. This paper utilises areal surface characterization, areal auto-correlation function (AACF) and pattern analysis to illustrate the effect of tool wear on the workpiece surface. The result shows that: (1) tool wear, previously difficult to detect will influence almost all of the areal surface parameters; (2) the pattern features of AACF spectrum can reflect the subtle surface texture variation with increasing tool wear. The authors consider that, combined analysis of the surface roughness and its AACF spectrum are a good choice for monitoring the tool wear state especially with the latest developments in on-machine surface metrology
- âŚ