scholarly journals MH370 Controlled Eastward Veering and Descent After the 6th Arc

2021 ◽  
Author(s):  
Vincent Lyne
Keyword(s):  
Satellite Data ◽  
High Speed ◽  
The South ◽  
Burst Frequency ◽  
Communication Signals ◽  
Vertical Descent ◽  
Scenario Analyses ◽  
Doppler Shifts ◽  
Data Points ◽  
Malaysian Airlines

Abstract Past expert analyses of communication signals from missing Malaysian Airlines MH370 reconciled Burst Frequency Offset (BFO) errors up to the 6th of 7 arcs for a southerly track. After the 6th arc, the Satellite Data Unit (SDU) power-up or reboot resulted in settling errors in the last two data points that were ignored (first search) and later bounded (second search). For the second search, investigators invoked a high-speed vertical descent to account for BFO errors for the south track fuel-starved scenario. Two searches disappointingly failed to find the implied violent-crash site. We report that interpretations were flawed in suggesting the plane dived vertically, as investigators did not recognize that BFO extrapolations implicitly implied mathematically that the plane was also cruising along the south track, but with no fuel. Our reanalysis used the “Penang Longitude” (PL) theory that predicted a similar southerly track to the 6th arc, and that MH370 subsequently veered eastwards and descended. Doppler Shifts from vertical motions were replaced with plausible horizontal veering and declination of a high-speed aircraft. Veering predicted by the PL theory plus controlled descent plausibly accounts for nominal 7th arc BFO discrepancies for the warm-reboot scenario. We conclude that the fuel-starvation scenario analyses wrongly implied a vertical high-speed crash that ignored the impossible implicit southerly cruise, with no fuel, assumption. Instead, MH370 was piloted to a precise glide landing under power, east of the 7th arc.

MH370 Eastward Descent After the 6th Arc

2021 ◽  
Author(s):  
Vincent Lyne
Keyword(s):  
Satellite Data ◽  
Doppler Shift ◽  
High Speed ◽  
Frequency Offset ◽  
Deep Hole ◽  
The South ◽  
Burst Frequency ◽  
Malaysian Airlines ◽  
High Uncertainty

Abstract Past analyses of satellite and phone signals from missing Malaysian Airlines MH370 reconciled Burst Frequency Offset (BFO) errors up to the 6th of 7 arcs for a southerly track. After the 6th arc, the Satellite Data Unit (SDU) power-up or reboot resulted in settling errors. Investigators bounded these but needed to invoke a high-speed descent for nominal errors that remained from assuming the southerly track continued to the 7th arc. However, the implied violent-crash site was not found nor supported by damage found on debris, which instead suggested a glided landing. In our reanalysis, we relaxed the south track assumption and used the “Penang Longitude” (PL) theory that predicted a similar southerly track to the 6th arc, and that MH370 subsequently veered eastwards and descended. In essence, we simply replaced the Doppler Shift from vertical motions with horizontal veering of a high-speed aircraft. Our results suggests that veering predicted by the PL theory plus controlled descent plausibly accounts for nominal 7th arc BFO discrepancies. Synergistic resolution of observation by this theory suggests that MH370 did not violently crash at the 7th arc. Instead MH370 headed east towards a glide landing, predicted by the PL theory to be where the longitude of Penang intersects the 33oS latitude at a deep hole. The main lesson to learn is that all plausible scenarios need to be considered for complex high-uncertainty problems.

scholarly journals Spatiotemporal Variability of Surface Phytoplankton Carbon and Carbon-to-Chlorophyll a Ratio in the South China Sea Based on Satellite Data

2020 ◽  
Vol 13 (1) ◽  
pp. 30
Author(s):  
Wenlong Xu ◽  
Guifen Wang ◽  
Long Jiang ◽  
Xuhua Cheng ◽  
Wen Zhou ◽  
...  
Keyword(s):  
South China Sea ◽  
Chlorophyll A ◽  
South China ◽  
Satellite Data ◽  
Phytoplankton Biomass ◽  
The South China Sea ◽  
Spatiotemporal Variability ◽  
The South ◽  
Chl A ◽  
China Sea

The spatiotemporal variability of phytoplankton biomass has been widely studied because of its importance in biogeochemical cycles. Chlorophyll a (Chl-a)—an essential pigment present in photoautotrophic organisms—is widely used as an indicator for oceanic phytoplankton biomass because it could be easily measured with calibrated optical sensors. However, the intracellular Chl-a content varies with light, nutrient levels, and temperature and could misrepresent phytoplankton biomass. In this study, we estimated the concentration of phytoplankton carbon—a more suitable indicator for phytoplankton biomass—using a regionally adjusted bio-optical algorithm with satellite data in the South China Sea (SCS). Phytoplankton carbon and the carbon-to-Chl-a ratio (θ) exhibited considerable variability spatially and seasonally. Generally, phytoplankton carbon in the northern SCS was higher than that in the western and central parts. The regional monthly mean phytoplankton carbon in the northern SCS showed a prominent peak during December and January. A similar pattern was shown in the central part of SCS, but its peak was weaker. Besides the winter peak, the western part of SCS had a secondary maximum of phytoplankton carbon during summer. θ exhibited significant seasonal variability in the northern SCS, but a relatively weak seasonal change in the western and central parts. θ had a peak in September and a trough in January in the northern and central parts of SCS, whereas in the western SCS the minimum and maximum θ was found in August and during October–April of the following year, respectively. Overall, θ ranged from 26.06 to 123.99 in the SCS, which implies that the carbon content could vary up to four times given a specific Chl-a value. The variations in θ were found to be related to changing phytoplankton community composition, as well as dynamic phytoplankton physiological activities in response to environmental influences; which also exhibit much spatial differences in the SCS. Our results imply that the spatiotemporal variability of θ should be considered, rather than simply used a single value when converting Chl-a to phytoplankton carbon biomass in the SCS, especially, when verifying the simulation results of biogeochemical models.

scholarly journals Odra: Naval and Merchant Vessels (Maritime science heritage: Sanatan Nau vigyan: Select discussions)

2021 ◽  
Vol 4 (2) ◽  
pp. 253758
Author(s):  
Deepak Bhattacharya ◽  
Sahadeva Sahoo
Keyword(s):  
Real Time ◽  
High Speed ◽  
East Asian ◽  
Numerical Calculations ◽  
Maritime History ◽  
The South ◽  
Time Modeling

Odra (riparian) is a historical entity, a synonym for the Kalinga empire (India) which was maritime in nature and had a robust seafaring heritage. In this paper, the south-east Asian archipelago nexus is touched upon, along with less well known aspects of Indo-Asian maritime history. Historically-dated artifacts are presented; naval and merchandise issues ranging from the period c.1200 to 1900 C.E., are discussed. A possible depiction of the empire’s fleet (c.12th C.E) is conceptualized. Boat-related numerical calculations are adduced, and associated physics and mechanics of ocean sailing are discussed. Ancient high speed and stable barges are discussed. In-continuum heritage practice and real-time modeling are presented.

scholarly journals High-speed optical diagnostic that uses interference filters to measure Doppler shifts

2004 ◽  
Vol 75 (10) ◽  
pp. 4077-4081 ◽  
Author(s):  
S. F. Paul ◽  
C. J. Cates ◽  
M. E. Mauel ◽  
D. A. Maurer ◽  
G. A. Navratil ◽  
...  
Keyword(s):  
High Speed ◽  
Interference Filters ◽  
Doppler Shifts ◽  
Optical Diagnostic

Trend Analysis with a New Global Record of Tropical Cyclone Intensity

2013 ◽  
Vol 26 (24) ◽  
pp. 9960-9976 ◽  
Author(s):  
James P. Kossin ◽  
Timothy L. Olander ◽  
Kenneth R. Knapp
Keyword(s):  
Tropical Cyclone ◽  
Indian Ocean ◽  
Satellite Data ◽  
Formal Analysis ◽  
P Value ◽  
Tropical Cyclone Intensity ◽  
The South ◽  
Cyclone Intensity ◽  
The North ◽  
South Indian

Abstract The historical global “best track” records of tropical cyclones extend back to the mid-nineteenth century in some regions, but formal analysis of these records is encumbered by temporal heterogeneities in the data. This is particularly problematic when attempting to detect trends in tropical cyclone metrics that may be attributable to climate change. Here the authors apply a state-of-the-art automated algorithm to a globally homogenized satellite data record to create a more temporally consistent record of tropical cyclone intensity within the period 1982–2009, and utilize this record to investigate the robustness of trends found in the best-track data. In particular, the lifetime maximum intensity (LMI) achieved by each reported storm is calculated and the frequency distribution of LMI is tested for changes over this period. To address the unique issues in regions around the Indian Ocean, which result from a discontinuity introduced into the satellite data in 1998, a direct homogenization procedure is applied in which post-1998 data are degraded to pre-1998 standards. This additional homogenization step is found to measurably reduce LMI trends, but the global trends in the LMI of the strongest storms remain positive, with amplitudes of around +1 m s−1 decade−1 and p value = 0.1. Regional trends, in m s−1 decade−1, vary from −2 (p = 0.03) in the western North Pacific, +1.7 (p = 0.06) in the south Indian Ocean, +2.5 (p = 0.09) in the South Pacific, to +8 (p < 0.001) in the North Atlantic.

scholarly journals Satellite data lift the veil on offshore platforms in the South China Sea

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Yongxue Liu ◽  
Chao Sun ◽  
Jiaqi Sun ◽  
Hongyi Li ◽  
Wenfeng Zhan ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Satellite Data ◽  
The South China Sea ◽  
Offshore Platforms ◽  
The South ◽  
China Sea ◽  
The Veil

A New Class of Asynchronous Rotordynamic Response in High-Speed Rotors

2007 ◽  
Author(s):  
Fredric F. Ehrich
Keyword(s):  
High Speed ◽  
Critical Frequency ◽  
Piecewise Linear ◽  
Dominant Frequency ◽  
Data Points ◽  
Subharmonic Response ◽  
Single Mass ◽  
Similar Appearance ◽  
The Individual ◽  
Representative Points

Virtually all of the nonlinear rotordynamic phenomena studied in the past result in excitation of rotor response at a dominant frequency at or near the critical frequency at rotational speeds other than the critical speed. In experimental work on a “macro-rig” of a micro-rotor in development some years ago at the Gas Turbine Laboratory of MIT, an unforeseen array of asynchronous response frequencies at other than the critical were noted when the rotor was operated at both subcritical and supercritical speeds. However, those responses were not explored in detail at the time. The patterned responses were apparently related to subharmonic and ultra-subharmonic response, but at frequencies lower than the critical frequency. More recently, the author noted a similar pattern of rotordynamic response in the course of operation at subcritical of an experimental turbomachinery component which was experiencing a local rub between the rotor and stator of an interstage seal. Data from that incident revealed a pattern of asynchronous response that had a very similar appearance to the earlier observation. Using a simple numerical model of a rotor employing a single mass mounted on a massless shaft and a piecewise linear (that is, a bilinear) bearing support stiffness to represent the system, it was possible to replicate the response at individual representative points over a range of sub-, trans-, and supercritical high-speed rotor operation. A generalized expression was derived inductively to represent the individual data points. The resultant pattern of data replicated the patterns of data from the two test vehicles which originally inspired the investigation and suggested the means of their suppression where their presence might be undesirable.

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