time inversion
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2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sungjoon Park ◽  
Yoonseok Hwang ◽  
Hong Chul Choi ◽  
Bohm-Jung Yang

AbstractAcoustic phonon is a classic example of triple degeneracy point in band structure. This triple point always appears in phonon spectrum because of the Nambu–Goldstone theorem. Here, we show that this triple point can carry a topological charge $${\mathfrak{q}}$$ q that is a property of three-band systems with space-time-inversion symmetry. The charge $${\mathfrak{q}}$$ q can equivalently be characterized by the skyrmion number of the longitudinal mode, or by the Euler number of the transverse modes. We call triple points with nontrivial $${\mathfrak{q}}$$ q the topological acoustic triple point (TATP). TATP can also appear at high-symmetry momenta in phonon and spinless electron spectrums when Oh or Th groups protect it. The charge $${\mathfrak{q}}$$ q constrains the nodal structure and wavefunction texture around TATP, and can induce anomalous thermal transport of phonons and orbital Hall effect of electrons. Gapless points protected by the Nambu–Goldstone theorem form a new platform to study the topology of band degeneracies.


2021 ◽  
Vol 2099 (1) ◽  
pp. 012040
Author(s):  
A V Bondarenko ◽  
D Yu Kushnir ◽  
N N Velker ◽  
G V Dyatlov

Abstract Multi-frequency and multi-component extra-deep azimuthal resistivity measurements with depth of investigation of a few tens of meters provide advanced possibilities for mapping of complex reservoir structures. Inversion of the induction measurements set becomes an important technical problem. We present a regularized Levenberg–Marquardt algorithm for inversion of resistivity measurements in a 2D environment model with pixel-based resistivity distribution. The cornerstone of the approach is an efficient parallel algorithm for computation of resistivity tool signals and its derivatives with respect to the pixel conductivities using volume integral equation method. Numerical tests of the suggested approach demonstrate its feasibility for near real time inversion.


2021 ◽  
Author(s):  
Yi Yu Lai

Abstract Mutations of legendary Galileo falling bodies experiment with non-living objects in a non-isolated environment demonstrate that the recoverable internal motions of falling bodies can bind and polarize gravity over conventional Newtonian mass inertia. Bio quantum path experiments further interpret the binding mechanism and reveal the isolated logic restriction of Einstein’s equivalence principle. Mutations of the Cavendish experiment unveil 109 levels of gravitational differences between living and dead states. Mutations of the Galileo falling body experiments for living beings confirmed that such differences come from recoverable internal motion surface tension gravitational binding that can be calibrated as a measurable bio-inertia. We then calibrated the falling height difference for human in vivo bio-inertia on a commercial 10m diving platform and verified 98% of populations on Earth can safely be tested in this way with enough preparation training. In vivo lifetime gravitational binding curve that governs all biological parameters and reveals life evolutionary mechanisms becomes technologically feasible. These results, along with various facts, modulate the gravitational multi-surface tension region resonating model of in vivo bio quantum path inversion superposition. Photoelectric effect, PCR, GPCR, ancient CSF-ligament human Kungfu training systems, music harmonics, and board observations physically sustain this model. Newtonian Third Laws of motion are therefore evolved into Basic Laws of Evolution originates from surface tension non-unitary time inversion superposition that is different from the mathematical superposition in quantum mechanics; original memory negentropy is also disciplinarily integrated.


2021 ◽  
Author(s):  
Yasuo Amano ◽  
Yuko Omori ◽  
Maki Amano ◽  
Chisato Ando ◽  
Naoki Shinoda ◽  
...  

Abstract Myocardial tissue changes associated with chronic kidney disease (CKD) may lead to heart failure, serious ventricular arrhythmia, and sudden cardiac death. Here, we sought to determine usefulness of T1T2 mapping and texture analysis of T2-weighted short inversion time inversion recovery (STIR) and cine imaging to detect myocardial changes associated with CKD. We examined 34 patients with CKD and 10 controls using a 1.5 T system. T1 and T2 values of the septal myocardium were significantly greater in patients than in controls (P = 0.021 for T1 and P < 0.01 for T2). The open-access texture analysis software, including features reduction methods, selected one particular feature for T2-weighted STIR and another for cine imaging: vertical fraction for STIR and horizontal short-run emphasis for cine imaging, which were significantly lower in the patients with CKD than in the controls (P < 0.01 for both). Texture analysis was not significantly better than T1T2 mapping in detecting the myocardial tissue changes, whereas STIR suffered from image artifacts in 9 patients. In conclusion, additional T1T2 mapping or postprocessing texture analysis may be feasible for detection of myocardial tissue changes associated with CKD.


2021 ◽  
Author(s):  
Yi Yu Lai

Abstract Mutations of legendary Galileo falling bodies experiment with non-living objects in a non-isolated environment demonstrate that the recoverable internal motions of falling bodies can bind and polarize gravity over conventional Newtonian mass inertia. Bio quantum path experiments further interpret the binding mechanism and reveal the isolated logic restriction of Einstein’s equivalence principle. Mutations of the Cavendish experiment unveil 109 levels of gravitational differences between living and dead states. Mutations of the Galileo falling body experiments for living beings confirmed that such differences come from recoverable internal motion surface tension gravitational binding that can be calibrated as a measurable bio-inertia. We then calibrated the falling height difference for human in vivo bio-inertia on a commercial 10m diving platform and verified 98% of populations on Earth can safely be tested in this way with enough preparation training. In vivo lifetime gravitational binding curve that governs all biological parameters and reveals life evolutionary mechanisms becomes technologically feasible. These results, along with various facts, modulate the gravitational multi-surface tension region resonating model of in vivo bio quantum path inversion superposition. Photoelectric effect, PCR, GPCR, ancient CSF-ligament human Kungfu training systems, music harmonics, and board observations physically sustain this model. Newtonian Third Laws of motion are therefore evolved into Basic Laws of Evolution originates from surface tension non-unitary time inversion superposition that is different from the mathematical superposition in quantum mechanics; original memory negentropy is also disciplinarily integrated.


2021 ◽  
Author(s):  
Ahmed Zarroug El Sedeq ◽  
Neal Hughes ◽  
Tore Oian ◽  
Piotr Byrski ◽  
Jean-Michel Denichou ◽  
...  

Abstract Dvalin field, discovered in 2010-2012. The location of this field is in the Norwegian Sea, as shown in (Figure 1). Dvalin field is an HPHT gas field in Middle Jurassic sandstone in the Garn and Ile Formations – the former being homogeneous with better reservoir properties, during the later heterogenous with low quality. (DVALIN, 2020) The well 6507/7-Z-2 H objective is to produce hydrocarbons from the Jurassic reservoir section of the Dvalin field safely and cost-effectively. The well was planned to be drilled near vertical in the reservoir section and TD'ed at a maximum depth corresponding to the Garn Formation base. After the productivity results from Z-3-H well came in at the low end of expectations, it was evaluated and decided to change the well profile of the Z-2-H well from vertical reservoir penetration to a horizontal profile; to have two penetrations with a minimum of 150m MD separation in the upper high permeable streak and then drop to penetrate lower high permeable streak. This decision was conducted only three days before starting the 17.5-inch section on the subject well. One Team culture was the key to achieving this significant change successfully. The decision to change the well-profile was conducted after a thorough engineering evaluation, including offset well analysis, which was very limited as the closest horizontal well was more than 40 km away. As the well was not planned as a horizontal well, departure between the surface location and Target Easting & Northing was minimal. Therefore, a high turn and deeper inclination build were required, which added some complexity to the well design. One of the additional primary risks related to this change of trajectory design is deploying a more complex BHA design in the reservoir section with a full suite of LWD technologies run in an HT environment. In the planning phase, special consideration was needed to accurately simulate the expected circulating temperature and have proper procedures in place for temperature management and control. Being the first horizontal well in the field, thus detailed planning was key for successful execution. Ultra-Deep Azimuthal Resistivity Tool (UDAR) Reservoir-Mapping capability was considered to help optimize the landing and navigate within the reservoir section. A feasibility study was conducted, and a 2-receiver Ultra Deep Azimuthal Resistivity Tool BHA configuration was selected and deployed. During the execution, the Ultra Deep Azimuthal Resistivity Tool real-time inversion mapped the reservoir geometry, revealing resistive layers within the Garn formation, thereby facilitating optimal placement of the well to achieve the set objectives. The well execution was largely considered flawless, with the real-time Ultra Deep Azimuthal Resistivity Tool data and corresponding interpretations facilitating decisions.


Geosciences ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 262
Author(s):  
Michael S. Zhdanov ◽  
Michael Jorgensen ◽  
Leif Cox

Different geophysical methods provide information about various physical properties of rock formations and mineralization. In many cases, this information is mutually complementary. At the same time, inversion of the data for a particular survey is subject to considerable uncertainty and ambiguity as to causative body geometry and intrinsic physical property contrast. One productive approach to reducing uncertainty is to jointly invert several types of data. Non-uniqueness can also be reduced by incorporating additional information derived from available geological and/or geophysical data in the survey area to reduce the searching space for the solution. This additional information can be incorporated in the form of a joint inversion of multiphysics data. This paper presents an overview of the main ideas and principles of novel methods of joint inversion, developed over the last decade, which do not require a priori knowledge about specific empirical or statistical relationships between the different model parameters and/or their attributes. These approaches are designated as follows: (1) Gramian constraints; (2) Gramian-based structural constraints; (3) localized Gramian constraints; and (4) joint focusing constraints. We provide a short description of the mathematical foundations of each of these approaches and discuss the practical aspects of their applications in mineral exploration.


Author(s):  
Jing Zou ◽  
Luguang Chen ◽  
Hongbin Li ◽  
Guoping Zhang ◽  
Ilmari Pyykkö ◽  
...  

Abstract Background It is still challenging to detect endolymphatic hydrops (EH) in patients with Meniere’s disease (MD) using MRI. The aim of the present study was to optimize a sensitive technique generating strong contrast enhancement from minimum gadolinium–diethylenetriamine pentaacetic acid (Gd–DTPA) while reliably detecting EH in the inner ear, including the apex. Materials and methods All imaging was performed using a 3.0 T MR system 24 h after intratympanic injection of low-dose Gd–DTPA. Heavily T2-weighted 3-dimensional fluid-attenuated inversion recovery reconstructed with magnitude and zero-filled interpolation (hT2W–FLAIR–ZFI) was optimized and validated in phantom studies and compared with medium inversion time inversion recovery imaging with magnitude reconstruction (MIIRMR). The following parameters were used in hT2W–FLAIR–ZFI: repetition time 14,000 ms, echo time 663 ms, inversion time 2900 ms, flip angle 120°, echo train length 271, and field of view 166 × 196 mm2. Results MRI obtained using hT2W–FLAIR–MZFI yielded high-quality images with sharper and smoother borders between the endolymph and perilymph and a higher signal intensity ratio and more homogenous perilymph enhancement than those generated with MIIRMR (p < 0.01). There were predominantly grade II EHs in the cochleae and grade III EHs in the vestibule in definite MD. EH was detected in the apex of 11/16 ipsilateral ears, 3/16 contralateral ears in unilateral definite MD and 3/6 ears in bilateral MD. Conclusions The novel hT2W–FLAIR–MZFI technique is sensitive and demonstrates strong and homogenous enhancement by minimum Gd–DTPA in the inner ear, including the apex, and yields high-quality images with sharp borders between the endolymph and perilymph.


2021 ◽  
Vol 43 (2) ◽  
pp. 28-44
Author(s):  
T. Janik ◽  
V. Starostenko ◽  
P. Aleksandrowski ◽  
T. Yegorova ◽  
W. Czuba ◽  
...  

The wide-angle reflection and refraction (WARR) TTZ-South transect carried out in 2018 crosses the SW region of Ukraine and the SE region of Poland. The TTZ-South profile targeted the structure of the Earth’s crust and upper mantle of the Trans-European Suture Zone, as well as the southwestern segment of the East European Craton (slope of the Ukrainian Shield). The ~550 km long profile (~230 km in Poland and ~320 km in western Ukraine) is an extension of previously realized projects in Poland, TTZ (1993) and CEL03 (2000). The deep seismic sounding study along the TTZ-South profile using TEXAN and DATA-CUBE seismic stations (320 units) made it possible to obtain high-quality seismic records from eleven shot points (six in Ukraine and five in Poland). This paper presents a smooth P wave velocity model based on first-arrival travel-time inversion using the FAST (First Arrival Seismic Tomography) code. The obtained image represents a preliminary velocity model which, according to the P wave velocities, consists of a sedimentary layer and the crystalline crust that could comprise upper, middle and lower crustal layers. The Moho interface, approximated by the 7.5 km/s isoline, is located at 45—47 km depth in the central part of the profile, shallowing to 40 and 37 km depth in the northern (Radom-Łysogуry Unit, Poland) and southern (Volyno-Podolian Monocline, Ukraine) segments of the profile, respectively. A peculiar feature of the velocity cross-section is a number of high-velocity bodies distinguished in the depth range of 10—35 km. Such high-velocity bodies were detected previously in the crust of the Radom-Łysogуry Unit. These bodies, inferred at depths of 10—35 km, could be allochthonous fragments of what was originally a single mafic body or separate mafic bodies intruded into the crust during the break-up of Rodinia in the Neoproterozoic, which was accompanied by considerable rifting. The manifestations of such magmatism are known in the NE part of the Volyno-Podolian Monocline, where the Vendian trap formation occurs at the surface.


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