scholarly journals Locating Graves with Geophysics

2021 ◽  
Author(s):  
Ian Moffat
Keyword(s):  
Physical Properties ◽  
Survey Methodology ◽  
Successful Outcome ◽  
Density Data ◽  
Non Invasive ◽  
Geophysical Techniques ◽  
Comprehensive Survey ◽  
Survey Strategy ◽  
Ultrahigh Density ◽  
Application Specific

The detection and mapping of unmarked graves is a significant focus of many archaeological and forensic investigations however traditional methods such as probing, forensic botany, cadaver dogs or dowsing are often ineffective, slow to cover large areas or excessively invasive. Geophysics offers an appealing alternative suitable for the rapid non invasive investigation of large areas. Unfortunately graves are a challenging target with no diagnostic geophysical response and so the use of a rigorous application-specific methodology is essential for a successful outcome. The most important inclusions in a successful survey methodology include ultrahigh density data, the use of multiple geophysical techniques to validate results based on several physical properties, excellent quality positioning and intensive site recording. Regardless of the methodology applied, geophysics should not be considered a panacea for locating all graves on all sites but should be used as an integral part of a comprehensive survey strategy.

The use of geophysical prospecting for imaging active faults in the Roer Graben, Belgium

Geophysics ◽  
2001 ◽  
Vol 66 (1) ◽  
pp. 78-89 ◽  
Author(s):  
Donat Demanet ◽  
François Renardy ◽  
Kris Vanneste ◽  
Denis Jongmans ◽  
Thierry Camelbeeck ◽  
...  
Keyword(s):  
High Resolution ◽  
Physical Properties ◽  
Fault Zone ◽  
Geophysical Methods ◽  
Depth Range ◽  
Electrical Tomography ◽  
Reflection Seismic ◽  
Refraction Seismic ◽  
Geophysical Surveys ◽  
Geophysical Techniques

As part of a paleoseismological investigation along the Bree fault scarp (western border of the Roer Graben), various geophysical methods [electrical profiling, electromagnetic (EM) profiling, refraction seismic tests, electrical tomography, ground‐penetrating radar (GPR), and high‐resolution reflection seismic profiles] were used to locate and image an active fault zone in a depth range between a few decimeters to a few tens of meters. These geophysical investigations, in parallel with geomorphological and geological analyses, helped in the decision to locate trench excavations exposing the fault surfaces. The results could then be checked with the observations in four trenches excavated across the scarp. Geophysical methods pointed out anomalies at all sites of the fault position. The contrast of physical properties (electrical resistivity and permittivity, seismic velocity) observed between the two fault blocks is a result of a differences in the lithology of the juxtaposed soil layers and of a change in the water table depth across the fault. Extremely fast techniques like electrical and EM profiling or seismic refraction profiles localized the fault position within an accuracy of a few meters. In a second step, more detailed methods (electrical tomography and GPR) more precisely imaged the fault zone and revealed some structures that were observed in the trenches. Finally, one high‐resolution reflection seismic profile imaged the displacement of the fault at depths as large as 120 m and filled the gap between classical seismic reflection profiles and the shallow geophysical techniques. Like all geophysical surveys, the quality of the data is strongly dependent on the geologic environment and on the contrast of the physical properties between the juxtaposed formations. The combined use of various geophysical techniques is thus recommended for fault mapping, particularly for a preliminary investigation when the geological context is poorly defined.

Fuel Composition Effects on Forced Ignition of Liquid Fuel Sprays

2018 ◽  
Author(s):  
Sheng Wei ◽  
Brandon Sforzo ◽  
Jerry Seitzman
Keyword(s):  
Physical Properties ◽  
Liquid Fuel ◽  
Chemical Properties ◽  
Reaction Rates ◽  
High Energy ◽  
Fuel Spray ◽  
Successful Outcome ◽  
Fuel Composition ◽  
Ignition Probability ◽  
Fuel Sprays

In gas turbine combustors, ignition is achieved by using sparks from igniters to start a flame. The process of sparks interacting with fuel/air mixture and creating self-sustained flames is termed forced ignition. Physical and chemical properties of a liquid fuel can influence forced ignition. The physical effects manifest through processes such as droplet atomization, spray distribution, and vaporization rate. The chemical effects impact reaction rates and heat release. This study focuses on the effect of fuel composition on forced ignition of fuel sprays in a well-controlled flow with a commercial style igniter. A facility previously used to examine prevaporized, premixed liquid fuel-air mixtures is modified and employed to study forced ignition of liquid fuel sprays. In our experiments, a wall-mounted, high energy, recessed cavity discharge igniter operating at 15 Hz with average spark energy of 1.25 J is used to ignite liquid fuel spray produced by a pressure atomizer located in a uniform air coflow. The successful outcome of each ignition events is characterized by the (continued) presence of chemiluminescence 2 ms after spark discharge, as detected by a high-speed camera. The ignition probability is defined as the fraction of successful sparks at a fixed condition, with the number of events evaluated for each fuel typically in the range 600–1200. Ten fuels were tested, including standard distillate jet fuels (e.g., JP-8 and Jet-A), as well as many distillate and alternative fuel blends, technical grade n-dodecane, and surrogates composed of a small number of components. During the experiments, the air temperature is controlled at 27 C and the fuel temperature is controlled at 21 C. Experiments are conducted at a global equivalence ratio of 0.55. Results show that ignition probabilities correlate strongly to liquid fuel viscosity (presumably through droplet atomization) and vapor pressure (or recovery temperature), as smaller droplets of a more volatile fuel would lead to increased vaporization rates. This allows the kernel to transition to a self-sustained flame before entrainment reduces its temperature to a point where chemical rates are too slow. Chemical properties of the fuel showed little influence, except when the fuels had similar physical properties. This result demonstrates that physical properties of liquid fuels have dominating effects on forced ignition of liquid fuel spray in coflow air.

scholarly journals Anthracene-Based Down-Converting Copolymers for Non-Invasive Optogenetic Techniques

2020 ◽  
Author(s):  
David French ◽  
Aundrea F. Bartley ◽  
Kavitha Abiraman ◽  
Micah Bagley ◽  
Benjamin Grant ◽  
...  
Keyword(s):  
Absorption Spectrum ◽  
Methyl Methacrylate ◽  
Physical Properties ◽  
Emission Intensity ◽  
High Energy ◽  
Neuronal Cultures ◽  
Non Invasive ◽  
Solid States ◽  
Neurological Response ◽  
Down Conversion

<p>The down-conversion of high energy light with a fluorescent material may provide sufficient emission intensity to invoke a measurable neurological response in optogentically-active neurons. This work describes the use of anthracene-containing copolymers for use as a fixed emission material in optogenetic electrophysiology to demonstrate the feasibility of this technique. An anthracene-modified methacrylate was synthesized and copolymerized with methyl methacrylate to produce glassy copolymers with physical properties like those of poly(methyl methacrylate) (PMMA). The fluorescence in both solution and solid states are like those of pure anthracene and overlap fully with the absorption spectrum of channelrhodpsin-2. Scintillation is observed but is weak compared to fluorescence. The copolymers were found to be non-toxic to neuronal cultures. Whole cell patching measured the voltage changes of neurons under UV-irradiation in the absence and presence of a copolymer film. Increased frequencies and amplitudes of electrical events were observed in the presence of the polymers. </p> <div> <hr> </div>

scholarly journals Researching Same Sex Domestic Violence: Constructing a Survey Methodology

2008 ◽  
Vol 13 (1) ◽  
pp. 174-187 ◽  
Author(s):  
Melanie McCarry ◽  
Marianne Hester ◽  
Catherine Donovan
Keyword(s):  
Domestic Violence ◽  
Survey Methodology ◽  
Community Survey ◽  
Heterosexual Relationships ◽  
Same Sex ◽  
Gay Male ◽  
Wide Range ◽  
Comprehensive Survey ◽  
The Uk ◽  
Survey Approach

The article discusses the issues and problems that need to be addressed in the development of a comprehensive survey approach to explore same sex domestic violence in relationships involving individuals identifying as lesbian, gay male, bisexual, transgender or queer (LGBT&Q). It draws on the most detailed study to date in the UK comparing love and domestic violence in same-sex and heterosexual relationships. The survey methodology built on previous research, attempting in particular to overcome the limitations of earlier studies; and to produce data that could be compared with existing data on domestic violence in both heterosexual and LGBT&Q communities. The result was a questionnaire that reflected a wide range of abusive behaviours; examined impact of the violence alongside a quantification of particular acts; took into account experience of violence from a partner, as well as use of violence against that partner; and incorporated issues related to equality/inequality and dependency. The questionnaire was successfully distributed across the UK to provide a national ‘same sex community’ survey of problems in relationships and domestic violence.

Progress in materials and technologies for ultrahigh density data storage*

2003 ◽  
Vol 13 (4) ◽  
pp. 247-253
Author(s):  
Huimeng Wu ◽  
Yanlin Song ◽  
Yongqiang Wen ◽  
Tong Zhao ◽  
Hongjun Gao ◽  
...  
Keyword(s):  
Data Storage ◽  
Density Data ◽  
Ultrahigh Density
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