Time‐lapse VSP test results demonstrate good repeatability for both land‐vibrator and marine air‐gun VSP surveys in Middle East carbonates

Oxygen is an important parameter for organic-waste composting, and continuous control of the oxygen in a composting pile may be beneficial. The oxygen consumption rate can be used to measure the degree of biological oxidation and decomposition of organic matter. However, without having a real-time online device to monitor oxygen levels in the composting pile, the adjustment and optimization of the composting process cannot be directly implemented. In the present study, we researched and developed such a system, and then tested its stability, reliability, and characteristics. The test results showed that the equipment was accurate and stable, and produced good responses with good repeatability. The equilibrium time required to detect oxygen concentration in the composting pile was 50 s, and the response time for oxygen detection was less than 2 s. The equipment could monitor oxygen concentration online and in real time to optimize the aeration strategy for the compost depending on the concentration indicated by the oxygen-measuring equipment.

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A long-offset seismic reflection and refraction study of the Gippsland and Bass Basins from onshore recording of a marine air-gun source

Exploration Geophysics ◽

10.1071/eg989293 ◽

1989 ◽

Vol 20 (2) ◽

pp. 293

Author(s):

C.D.N. Collins ◽

J.P. Cull ◽

J.B. Willcox ◽

J.B. Colwell

Keyword(s):

Deep Structure ◽

Seismic Refraction ◽

Reflection And Refraction ◽

Air Gun ◽

Long Offset ◽

Deep Crustal Structure ◽

Basin Formation ◽

Seismic Refraction Data ◽

Marine Air ◽

Refraction Data

Seismic refraction data were obtained for the Bass and Gippsland Basins during the 1988 cruise of the BMR research vessell "Rig Seismic". Seismic recorders were deployed on land by BMR and Monash University to record long-offset wide-angle reflection and refraction data using the ship's air-guns as the energy source. Preliminary results have now been obtained from these data providing information on deep crustal structure related to the basin formation. Two crustal layers have been detected with velocities of 4.5 km/s increasing to 7.4 km/s (unreversed) at depths exceeding 20 km. Additional data have now been obtained over a traverse length of 170 km to provide constraints on the deep structure of Bass Strait and the Lachlan Fold Belt in Victoria and Tasmania.

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On the theory of air‐gun bubble interactions

Geophysics ◽

10.1190/1.1442454 ◽

1988 ◽

Vol 53 (2) ◽

pp. 192-200 ◽

Cited By ~ 4

Author(s):

R. C. Bailey ◽

P. B. Garces

Keyword(s):

Ambient Pressure ◽

Bubble Radius ◽

Dynamical Equations ◽

Local Pressure ◽

Know How ◽

R And D ◽

Bubble Interactions ◽

Interaction Terms ◽

Air Gun ◽

Marine Air

Calculation of the seismic signatures of marine air‐gun arrays often requires that the interactions among the bubbles from air guns be taken into account. The standard method of doing this is to use the Giles‐Johnston approximation in which a time‐dependent effective ambient pressure is calculated for each bubble as the sum of the true ambient pressure and the local pressure signals of all the other bubbles in the array. These effects of interaction have a relative importance in the dynamics proportional to (R/D), where R and D are the typical bubble radius and interbubble separation, respectively. To ensure that current methods of calculating signatures are accurate, it is necessary to know how good this approximation is. This paper shows that there are no interaction terms in the full dynamical equations proportional to [Formula: see text] or [Formula: see text], and that the errors of the Giles‐Johnston approximation are only of order [Formula: see text]. The Giles‐Johnston approximation is therefore justified even for fairly accurate signature calculations for noncoalescing bubbles. The analysis here also shows how to incorporate bubble motions and deformations into the dynamical equations, so that the errors can be reduced to order [Formula: see text] if desired.

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Microseismic monitoring of a Middle East carbonate reservoir: Minagish sensitivity test results

10.1190/1.3059177 ◽

2008 ◽

Cited By ~ 1

Author(s):

Emmanuel Gaucher ◽

Christophe Maisons ◽

Abdullatif Y. Al‐Kandari ◽

Kamal Al‐Atroshi ◽

Jassim M. Al‐Kanderi

Keyword(s):

Middle East ◽

Microseismic Monitoring ◽

Carbonate Reservoir ◽

Sensitivity Test ◽

Test Results

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Comparing the broadband acoustic frequency response of single, clustered, and arrays of marine air guns

Geophysics ◽

10.1190/geo2019-0768.1 ◽

2020 ◽

Vol 85 (3) ◽

pp. P27-P36

Author(s):

Martin Landrø ◽

Jan Langhammer

Keyword(s):

Acoustic Signal ◽

High Frequency ◽

High Speed ◽

Acoustic Stimulation ◽

Main Peak ◽

Water Tank ◽

High Frequency Signal ◽

Acoustic Frequency ◽

Air Gun ◽

Marine Air

Field data acquired from a seismic vessel by a seabed hydrophone is used to analyze the broadband response (10 Hz to 62.5 kHz) for various source configurations: single air guns, clustered air guns, and a full array consisting of 30 air guns. The various parts of the acoustic signal are analyzed in detail, and it is found that a high-frequency signal arriving prior to the main peak of a single air-gun signal most likely is caused by small vapor cavities collapsing at or close to the surface of the gun. This is confirmed by high-speed photographs taken when a small air gun is fired in a water tank. When the full array is used, a second type of cavitation signal is observed: ghost cavitation caused by acoustic stimulation by the negative pressure that is backscattered from the free surface. As this ghost signal from 30 different guns arrives at a specific location in the water, cavities might be formed, and they create a high-frequency acoustic signal.

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DESIGN OF PROTOTYPE ELECTRICAL FIRING DEVICE SMOKE POWDER BOMB INTEGRATED IN ANDROID

JOURNAL ASRO ◽

10.37875/asro.v11i1.214 ◽

2020 ◽

Vol 11 (1) ◽

pp. 174

Author(s):

Endin Tri Hartanto ◽

Bagus Irawan ◽

Sunarta Sunarta ◽

Atet Saputra

Keyword(s):

Armed Forces ◽

Voltage Source ◽

Test Results ◽

Power Sources ◽

Territorial Integrity ◽

Switching Power ◽

Foreign Countries ◽

Gsm Network ◽

Marine Air ◽

Firing System

Threats are any businesses and activities, both from domestic and foreign countries which are consideredendangering the Indonesian sovereignty, the territorial integrity of the country, and the safety of the wholenation. Military threats are threats that use organized armed forces that are judged to have abilities thatjeopardize the country's sovereignty, the territorial integrity of the country, and the safety of the whole nation.This smoke powder firing system is to utilize the internet network so that to trigger the smoke powder bomb canbe carried out from various places and anywhere the smoke powder weapons ignition can be carried out.Design and Composite Smoke Powder as a Marine, Air and Ground Defense Sabotage Weapon. This researchis expected to be able to contribute to sabotage cysts and deception of opponents. The main objective in thedesign of the building of Smoke Powder as a means of supporting smoke bomb training in a pattern to trick theenemy. In planning the bomb lighter system uses an electric lighter which is controlled remotely via an Androidphone call. The lighters used are gas stove lighters with 3 Volt dc battery voltage source. So that themicrocontroller device can regulate the flow of current to the lighter, the author uses a transistor that functionsas switching power sources to the lighter. The command for switching resources to a lighter is obtained from thecommand of an Android device. The test results show the system can work well, even though the constraintsoccur in the system, namely the GSM network which often interrupt.Keywords : Smoke powder, switching, Android, GSM.

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Screening for Stereopsis Using an Eye-Tracking Glasses-Free Display in Adults: A Pilot Study

Frontiers in Medicine ◽

10.3389/fmed.2021.814908 ◽

2022 ◽

Vol 8 ◽

Author(s):

Fang Liu ◽

Jing Zhao ◽

Tian Han ◽

Yang Shen ◽

Meng Li ◽

...

Keyword(s):

Eye Tracking ◽

High Myopia ◽

Patient Acceptance ◽

Test Results ◽

Display System ◽

Visual Fatigue ◽

Significant Difference ◽

Good Consistency ◽

Good Repeatability ◽

Tracking Technology

Purpose:To explore the feasibility and repeatability of a novel glasses-free display combined with random-dot stimulus and eye-tracking technology for screening stereopsis in adults.Methods:A total of 74 patients aged 18–44 years were recruited in this study (male: female, 32:42), including 33 patients with high myopia [≤ -6.0 diopters (D)] and 41 patients with moderate-to-low myopia (>-6.0 D). Stereopsis was measured using glasses-free, polarized, and Titmus stereotests. All patients completed a visual fatigue questionnaire after the polarized stereotest and glasses-free test. Kendall's W and Cohen's Kappa tests were used to evaluate repeatability and consistency of the glasses-free stereotest.Results:The stereotest results using the glasses-free monitor showed strong repeatability in the three consecutive tests (W = 0.968, P < 0.01) and good consistency with the polarized stereotest and Titmus test results (vs. polarization: Kappa = 0.910, P < 0.001; vs. Titmus: Kappa = 0.493, P < 0.001). Stereopsis levels of the high myopia group were significantly poorer than those of the moderate-to-low myopia group in three stereotest monitors (all P < 0.05). There was no significant difference in visual fatigue level between the polarized and the glasses-free display test (P = 0.72). Compared with the polarized test, 56.76% of patients preferred the glasses-free display and found it more comfortable, 20.27% reported both tests to be acceptable.Conclusions:In our adult patients, the new eye-tracking glasses-free display system feasibly screened stereopsis with good repeatability, consistency, and patient acceptance.

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Pengaruh Pemahaman Hidup Kudus Menurut 1 Tesalonika 4:1-8 terhadap Perilaku Seksual Remaja-Pemuda GPdI di Wilayah Sentani Timur Tengah

EPIGRAPHE: Jurnal Teologi dan Pelayanan Kristiani ◽

10.33991/epigraphe.v4i1.147 ◽

2020 ◽

Vol 4 (1) ◽

Author(s):

Priskila De Fretes

Keyword(s):

Sexual Behavior ◽

Middle East ◽

Quantitative Research ◽

Hypothesis Test ◽

Positive Influence ◽

Survey Method ◽

Test Results ◽

East Region ◽

Normality Test ◽

Middle East Region

This study aims to determine whether there is an influence of understanding of holy life according to 1 Thessalonians 4: 1-8 on the sexual behavior of GPdI youth/adolescents in the South East Sentani Region, to find out which dimensions affect the understanding of holy life according to 1 Thessalonians 4: 1-8 towards sexual behavior of youth/adolescents in GPdI Sentani Middle East Region, and to find out which background factors have the most influence on sexual behavior in youth/adolescents in GPdI Sentani Middle East Region. In this study the population was youth/adolescents in the Middle East Sentani Region GPdI totaling 123 people. This research will use a quantitative (positivist) approach. The research method used is a quantitative research design with a survey method, which is explanatory-confirmatory. The data collection methods and tools used in this study are questionnaire methods. Normality test shows the probability value 0.32> 0.05, then the data distribution proved normal. ANOVA test or F test, Fcount of 724.395 with sig. = 0.000 <0.05 means that the relationship between variables X with Y is positive. Simple linear regression test results through the SPSS 20.0 for Windows program, obtained a simple regression equation that is equal to = Y = -47,727 + 0.864X. This shows that there is a positive influence. Hypothesis test results, understanding of holy life according to 1 Thess. 4: 1-8 (X) has a positive effect on the sexual behavior of GPdI youth/adolescents in Sentani Middle East (Y). This is indicated by the value of t arithmetic (26,915)> t table (1,979) which means that Ho is rejected and Ha is accepted.

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Optimizing spatial distribution to minimize the inline directivity for a marine air-gun source

Geophysics ◽

10.1190/geo2019-0544.1 ◽

2020 ◽

Vol 85 (3) ◽

pp. P37-P44

Author(s):

Honglei Shen ◽

Chunhui Tao ◽

Thomas Elboth ◽

Hanchuang Wang ◽

Jianping Zhou ◽

...

Keyword(s):

Spatial Distribution ◽

High Resolution ◽

Directional Pattern ◽

Stimulation Mode ◽

Air Gun ◽

Air Water Interface ◽

Seismic Acquisition ◽

Highly Correlated ◽

Marine Air ◽

Mathematical Derivation

The spatial distribution of an air-gun array and the ghost reflection from the air-water interface cause a directional pattern of the source signature and introduce notches at certain frequencies. This significantly limits the bandwidth of the seismic data and the ability to obtain high-resolution subsurface imaging. With mathematical derivation and numerical simulation, we have determined that the inline directivity relies on the number of air guns and their spacing. Furthermore, the effective width of the take-off angles for an air-gun array is highly correlated with the reciprocal of the distance variance along the inline direction, which is subsequently used for optimizing the source design. For a normal horizontal source, one could adjust the distance between two consecutive air guns to improve the source signature. We optimize the spatial distribution for air guns along the inline and depth directions, that is, by using the synchronized multidepth stimulation mode, to minimize the inline directivity. Simulated results show that a six-gun composed multidepth source could be designed to achieve nearly identical energy distribution with up to ±30° take-off angle for the high-frequency end up to 250 Hz. This represents a significant improvement compared to a normal horizontal source and is more suitable for high-resolution seismic acquisition.

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