Estimation of travelling wave arrival time in longitudinal differential protections for multi-terminal HVDC systems

Abstrak Telah dilakukan pemetaan daerah rawan tsunami berdasarkan estimasi waktu tiba gelombang dan tutupan lahan di Kabupaten Kupang Provinsi Nusa Tenggara Timur menggunakan aplikasi Penginderaan Jauh dan Sistem Informasi Geografi. Penelitian ini bertujuan untuk mengidentifikasi, memetakan daerah rawan tsunami dan tingkat kerawanannya menurut estimasi waktu tiba gelombang dan tutupan lahan sebagai upaya mitigasi dampak bencana tsunami terhadap kepadatan penduduk. Metode penelitian secara umum dibagi dalam empat tahap utama yaitu pembangunan basis data berupa pembuatan peta tutupan lahan, peta gempa dan peta batimetri. Analisis data kerawanan dari peta tutupan lahan dan etimasi waktu tiba gelombang, penyajian hasil data dalam bentuk tingkat kerawanan masing-masing peta dan analisis hasil penelitian berupa tingkat kerawanan secara kualitatif masing-masing daerah titik pantau menurut peta tutupan lahan maupun estimasi waktu tiba gelombang. Selain itu, dampak kerawanan tsunami diklasifikasikan menurut tingkat kepadatan penduduk untuk kebutuhan mitigasi sebagai berikut Kecamatan Kupang Timur, Kupang Barat, Sulamu, Amfoang Timur, Semau, Semau Selatan, Amfoang Utara, Amfoang Barat Daya, Amfoang Barat Laut dan Fatuleu Barat. Kata kunci : Peta rawan tsunami, Penginderaan Jauh, Sistem Informasi Geografi, Estimasi Waktu Tiba Gelombang Abstract Mapping of hazard tsunami areas based on estimation of arrival time of wave and land cover in Kupang Regency of East Nusa Tenggara Province using remote sensing application and geographic information system has been done. The aims of this research are to mapping the hazard tsunami area and tsunami vulnerability level in Kupang Regency East Nusa Tenggara according to the estimated arrival time of the wave and land cover as an effort to mitigate the impact of the tsunami disaster on population density. These generally devided into four main phase namely development of database in the form of land cover map , seismic maps and bathymetry maps, data analysis of research results in the form of qualitative vulnerability of each monitoring area according to land cover map and estimated wave arrival time. Presentation of data results in the form of vulnerability level of each map and analysis and results analysis of research the form of vulnerability level of each map and analysis of research results in the form of qualitative vulnerability of each monitoring area according to land cover map and estimated wave arrival time. And then, the impact of tsunami vulnerability is classified according to population density levels for mitigation needs as follows Kupang Timur, Kupang Barat, Sulamu, Amfoang Timur, Semau, Semau Selatan, Amfoang Utara, Amfoang Barat Daya, Amfoang Barat Laut and Fatuleu Barat. Keywords: Tsunami Hazard Map, Remote Sensing, Geographic Information System, Estimated Time of arrival Wave

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Traveling wave arrival time detection for two-terminal non-contact measurement based on short time matrix pencil scheme

Electric Power Systems Research ◽

10.1016/j.epsr.2021.107747 ◽

2022 ◽

Vol 205 ◽

pp. 107747

Author(s):

Paul Oswald Kwasi Anane ◽

Dongsheng Cai ◽

Shaddrack Yaw Nusenu ◽

Jian Li ◽

Qi Huang ◽

...

Keyword(s):

Traveling Wave ◽

Arrival Time ◽

Matrix Pencil ◽

Contact Measurement ◽

Short Time ◽

Wave Arrival

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Joint microseismic event location and anisotropic velocity inversion with the cross double-difference method using downhole microseismic data

Geophysics ◽

10.1190/geo2019-0325.1 ◽

2020 ◽

Vol 85 (3) ◽

pp. KS63-KS73

Author(s):

Yangyang Ma ◽

Congcong Yuan ◽

Jie Zhang

Keyword(s):

Arrival Time ◽

Velocity Model ◽

P Wave ◽

Double Difference ◽

S Wave ◽

Arrival Times ◽

Monitoring Well ◽

The Cross ◽

Microseismic Event ◽

Wave Arrival

We have applied the cross double-difference (CDD) method to simultaneously determine the microseismic event locations and five Thomsen parameters in vertically layered transversely isotropic media using data from a single vertical monitoring well. Different from the double-difference (DD) method, the CDD method uses the cross-traveltime difference between the S-wave arrival time of one event and the P-wave arrival time of another event. The CDD method can improve the accuracy of the absolute locations and maintain the accuracy of the relative locations because it contains more absolute information than the DD method. We calculate the arrival times of the qP, qSV, and SH waves with a horizontal slowness shooting algorithm. The sensitivities of the arrival times with respect to the five Thomsen parameters are derived using the slowness components. The derivations are analytical, without any weak anisotropic approximation. The input data include the cross-differential traveltimes and absolute arrival times, providing better constraints on the anisotropic parameters and event locations. The synthetic example indicates that the method can produce better event locations and anisotropic velocity model. We apply this method to the field data set acquired from a single vertical monitoring well during a hydraulic fracturing process. We further validate the anisotropic velocity model and microseismic event locations by comparing the modeled and observed waveforms. The observed S-wave splitting also supports the inverted anisotropic results.

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Value of shear wave arrival time contour display in shear wave elastography for breast masses diagnosis

Scientific Reports ◽

10.1038/s41598-017-07389-0 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 6

Author(s):

Bang-Guo Zhou ◽

Dan Wang ◽

Wei-Wei Ren ◽

Xiao-Long Li ◽

Ya-Ping He ◽

...

Keyword(s):

Shear Wave ◽

Arrival Time ◽

Shear Wave Elastography ◽

Breast Masses ◽

Wave Arrival

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Shear wave arrival time estimates correlate with local speckle pattern

IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control ◽

10.1109/tuffc.2015.007171 ◽

2015 ◽

Vol 62 (12) ◽

pp. 2054-2067 ◽

Cited By ~ 11

Author(s):

Stephen A. Mcaleavey ◽

Laurentius O. Osapoetra ◽

Jonathan Langdon

Keyword(s):

Shear Wave ◽

Arrival Time ◽

Speckle Pattern ◽

Time Estimates ◽

Wave Arrival

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The Study of Automatic Picking of P and S Wave Arrival and Identification of Earthquake Sequence Pattern using Scalogram in Obspy (Python)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/873/1/012014 ◽

2021 ◽

Vol 873 (1) ◽

pp. 012014

Author(s):

Sri Kiswanti ◽

Indriati Retno Palupi ◽

Wiji Raharjo ◽

Faricha Yuna Arwa ◽

Nela Elisa Dwiyanti

Keyword(s):

Wavelet Transform ◽

Continuous Wavelet Transform ◽

Arrival Time ◽

Continuous Wavelet ◽

S Wave ◽

S Waves ◽

Automatic Picking ◽

Earthquake Record ◽

Initial Identification ◽

Wave Arrival

Abstract Initial identification on an earthquake record (seismogram) is something that needs to be done precisely and accurately. Moreover, the discovery of a series of unexpected successive earthquake events has caused unpreparedness for the community and related agencies in tackling these events. Determining the arrival time of the P and S waves becomes an important parameter to finding the location of the earthquake source (hypocenter) as well as further information related to the earthquake event. However, manual steps that are currently often used are considered to be less effective, because it requires a lot of time in the process. Continuous Wavelet Transform (CWT) analysis can be a solution for this problem. With further CWT analysis in the form of a scalogram, can help to determine the arrival time of P and S waves automatically (automatic picking) becomes simpler. In addition, further CWT analysis can also be utilized to help identify the sequence of earthquake events (foreshock, mainshock, aftershock) through the resulting scalogram pattern.

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