Spectral energy density for quarry explosions

1963 ◽  
Vol 53 (5) ◽  
pp. 989-996 ◽  
Author(s):  
G. E. Frantti
Keyword(s):  
Energy Density ◽  
Seismic Waves ◽  
Energy Levels ◽  
Total Duration ◽  
Seismic Energy ◽  
Body Waves ◽  
Propagation Path ◽  
Spectral Energy ◽  
Time Duration ◽  
Duration Time

Abstract Several explosions of varying time duration have been recorded at 156 km along a constant propagation path from a central Michigan limestone quarry. Energy density for body waves and surface waves is examined as a function of frequency and observed to peak between 1 and 10 cps. A correlation between spectral amplitudes and source duration time is revealed and is emphasized at shot durations which approximate the dominant period of seismic waves. A study of the data suggests that seismic energy levels may be controlled, in part, by regulating the time duration of delayed quarry blasts. This parameter (total duration time) has been generally neglected in published studies involving commercial blasts.

scholarly journals Liquefaction

2021 ◽  
pp. 301-321
Author(s):  
Chi-Yuen Wang ◽  
Michael Manga
Keyword(s):  
Experimental Data ◽  
Energy Density ◽  
Seismic Waves ◽  
Near Field ◽  
Laboratory Data ◽  
Seismic Energy ◽  
Silty Sand ◽  
Engineered Structures ◽  
Outstanding Question ◽  
Extensive Experimental Data

AbstractLiquefaction of the ground during earthquakes has long been documented and has drawn much attention from earthquake engineers because of its devastation to engineered structures. In this chapter we review a few of the best studied field cases and summarize insights from extensive experimental data critical for understanding the interaction between earthquakes and liquefaction. Despite the progress made in the last few decades, several outstanding problems remain unanswered. One is the mechanism for liquefaction beyond the near field, which has been abundantly documented in the field. This is not well understood because, according to laboratory data, liquefaction should occur only in the near field where the seismic energy density is great enough to cause undrained consolidation leading up to liquefaction. Another outstanding question is the dependence of liquefaction on the frequency of the seismic waves, where the current results from the field and laboratory studies are in conflict. Finally, while in most cases the liquefied sediments are sand or silty sand, well-graded gravel has increasingly been witnessed to liquefy during earthquakes and is not simply the result of entrainment by liquified sand. It is challenging to explain how pore pressure could build up in gravely soils and be maintained at a level high enough to cause liquefaction.

scholarly journals A quasi-monoenergetic short time duration compact proton source for probing high energy density states of matter

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. I. Apiñaniz ◽  
S. Malko ◽  
R. Fedosejevs ◽  
W. Cayzac ◽  
X. Vaisseau ◽  
...  
Keyword(s):  
Energy Density ◽  
Proton Beam ◽  
Dense Matter ◽  
High Energy ◽  
High Repetition Rate ◽  
High Energy Density ◽  
Time Duration ◽  
Ultrashort Pulse Laser ◽  
Proton Source ◽  
Short Time

AbstractWe report on the development of a highly directional, narrow energy band, short time duration proton beam operating at high repetition rate. The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted to a pencil-like narrow-band beam using a compact magnet-based energy selector. We experimentally demonstrate the production of a proton beam with an energy of 500 keV and energy spread well below 10$$\% $$ % , and a pulse duration of 260 ps. The energy loss of this beam is measured in a 2 $$\upmu $$ μ m thick solid Mylar target and found to be in good agreement with the theoretical predictions. The short time duration of the proton pulse makes it particularly well suited for applications involving the probing of highly transient plasma states produced in laser-matter interaction experiments. This proton source is particularly relevant for measurements of the proton stopping power in high energy density plasmas and warm dense matter.

Energy spectra for underground explosions and earthquakes

1963 ◽  
Vol 53 (5) ◽  
pp. 997-1005
Author(s):  
G. E. Frantti
Keyword(s):  
Energy Density ◽  
Frequency Dependence ◽  
Discrimination Problem ◽  
Seismic Source ◽  
Energy Spectra ◽  
Time Duration ◽  
Source Discrimination ◽  
Earthquake Energy

Abstract Energy density for the entire seismogram is examined as a function of frequency for underground explosions and earthquakes. Anomalous differences in the spectra appear to correlate with the time duration of the source. Ratios of aftershock to earthquake energy show a relatively flat frequency dependence. In contrast, corresponding ratios for nuclear shot-collapse events change rapidly with increasing frequency. Analysis of these data suggests that measurements of total seismogram energy might be usefully applied in the seismic source discrimination problem.

scholarly journals Effect of dietary energy density and folic acid supplementation on white striping occurrence and growth performance of broiler chickens

2021 ◽  
Author(s):  
Deborah Adewole ◽  
Janice L MacIsaac ◽  
Chengbo Yang
Keyword(s):  
Folic Acid ◽  
Energy Density ◽  
Growth Performance ◽  
Broiler Chickens ◽  
Energy Levels ◽  
Folic Acid Supplementation ◽  
Normal Breast ◽  
Dietary Energy ◽  
White Striping ◽  
Dietary Energy Density

Broilers were allocated to eight treatments consisting of two energy levels: Normal (NE) and High (HE), and four folic acid (FA) levels (2.2, 5, 10 and 15 ppm). On d 42, two male and two female chickens were euthanized per pen and white striping (WS) evaluation was performed on the Pectoralis major. Birds fed HE diets had reduced (P<0.05) FI and FCR than those on NE diets. With increasing FA levels, there was reduced (P<0.05) WS score, increased (P<0.05) normal breast fillet percentage in female but not in the male chickens. WS scores were higher (P<0.01) in male chickens than in the females.

scholarly journals Abbreviated (8 hours) versus Traditional (24 hours) Postpartum MgSO4 Prophylaxis in Severe Preeclampsia: A Randomised Control Trial

2021 ◽  
Author(s):  
Shyamal Dasgupta ◽  
Anindya Das ◽  
Anurag Mallick ◽  
Chiranjit Ghosh
Keyword(s):  
Magnesium Sulphate ◽  
Total Duration ◽  
Severe Preeclampsia ◽  
Randomised Control Trial ◽  
Controlled Study ◽  
P Value ◽  
Time Duration ◽  
Traditional Group ◽  
Suitable Alternative ◽  
Number Of Patients

Introduction: Preeclampsia is a multisystem disorder affecting pregnancy after 20 weeks of gestation featured by hypertension and proteinuria. Magnesium Sulphate (MgSO4) has been used for 24 hours following delivery to prevent eclampsia in patients with severe preeclampsia. Aim: To determine the need to continue magnesium sulphate therapy 8 hours following delivery. Materials and Methods: The double blinded randomised controlled study was performed in the Department of Gynaecology and Obstetrics at R.G. Kar Medical College, Kolkata, West Bengal, India, from 1st July 2015 to 30th June 2016. Total 90 patients with severe preeclampsia were randomised in two group. In group A MgSO4 was discontinued 8 hours following delivery (abbreviated group) and in the group B it was continued for 24 hours following delivery (traditional group). The primary objective of study was to determine the need to continue MgSO4 therapy 8 hours following delivery. Secondary objectives were monitoring time by doctors, nursing care time, postpartum ambulation time, duration of urinary catheterisation, minor complication like urinary tract infection, duration and total dose of MgSO4 therapy. In order to calculate statistical significance of the different variables in between two groups, Student’s independent sample’s t-test was used for normally distributed numerical values and Chi-square test or Fischer’s-exact test was used for unpaired proportion data. Results: In abbreviated group, the number of patients (n=1) who did not need to continue MgSO4 therapy beyond 8 hours following delivery as safety measures were statistically significant (p-value <0.0001) in comparison to traditional group. Total duration and dose of MgSO4 therapy were significantly less (p-value <0.0001) in the abbreviated group. There was statistically significant reduction in time from delivery to postpartum ambulation and duration of indwelling urinary catheter in the abbreviated group. Conclusion: The abbreviated (8 hours) regime of postpartum MgSO4 for seizure prophylaxis is a suitable alternative to the traditional (24 hours) regime.

scholarly journals Growth and feed utilization of Boer x Kacang crossbred goats offered total mixed rations of different protein and energy levels

2018 ◽  
Vol 22 (4) ◽  
pp. 188
Author(s):  
Simon P. Ginting ◽  
Kiston Simanihuruk ◽  
Antonius Antonius ◽  
Andi Tarigan
Keyword(s):  
Energy Density ◽  
Protein Level ◽  
Crude Protein ◽  
Energy Levels ◽  
Dietary Treatment ◽  
Feed Utilization ◽  
Metabolizable Energy ◽  
High Rate ◽  
Protein Levels ◽  
Crude Protein Level

The aim of this study was to evaluate the growth of and feed utilization by Boer x Kacang crosses goats fed on total mixed ration differing in protein and energy levels. Four total mixed rations combination were formulated to contain 16 and 18% crude protein and 2650 and 2850 Kcal ME/ kg DM (dried matter) energy density. Twenty-eight male Boer x Kacang crosses goats (14.5 ± 1.14 kg) and of age ranging from 4 to 5 months were randomly allocated to one of these four TMRs (total mixed rations) (7 animals/TMR). The effects of dietary treatment were assessed using the general linear model and significance of the diet effects was detected using Duncan’s multiple range test. Dry matter intake increased as metabolizable energy density of diet increased from 2650 to 2850 Kcal/kg DM, but it is not affected by increasing crude protein level from 16 to 18%. The average daily gains were not improved (P&gt;0.05) as the crude protein levels and metabolizable energy density of diet increased. Crude protein levels and ME density did not affect (P&gt;0.05) the DM, OM and energy digestibility, but NDF digestibility was affected by the ME density of diets (P&lt;0.05). Daily N intakes were greater (P&lt;0.0%) in goats received diets higher in the crude protein and metabolizable energy levels. At this high rate of feed intake this type of goats are able to gain optimally when offered feed with crude protein level of 16% and metabolizable energy density of 2850 Kcal/kg DM.

Are Synthetic Accelerograms Suitable for Local Seismic Response Analyses at Near-Field Sites?

2021 ◽  
Author(s):  
Francesca Mancini ◽  
Sebastiano D’Amico ◽  
Giovanna Vessia
Keyword(s):  
Seismic Response ◽  
Seismic Waves ◽  
Near Field ◽  
Central Italy ◽  
Propagation Path ◽  
Soil Behavior ◽  
Seismic Stations ◽  
Seismic Input ◽  
Local Seismic Response ◽  
Finite Fault

ABSTRACT Local seismic response (LSR) studies are considerably conditioned by the seismic input features due to the nonlinear soil behavior under dynamic loading and the subsurface site conditions (e.g., mechanical properties of soils and rocks and geological setting). The selection of the most suitable seismic input is a key point in LSR. Unfortunately, few recordings data are available at seismic stations in near-field areas. Then, synthetic accelerograms can be helpful in LSR analysis in urbanized near-field territories. Synthetic accelerograms are generated by simulation procedures that consider adequately supported hypotheses about the source mechanism at the seismotectonic region and the wave propagation path toward the surface. Hereafter, mainshocks recorded accelerograms at near-field seismic stations during the 2016–2017 Central Italy seismic sequence have been compared with synthetic accelerograms calculated by an extended finite-fault ground-motion simulation algorithm code. The outcomes show that synthetic seismograms can reproduce the high-frequency content of seismic waves at near-field areas. Then, in urbanized near-field areas, synthetic accelerograms can be fruitfully used in microzonation studies.

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