Studi Penjalaran Gelombang Laut di Pulau Panjang, Kabupaten Jepara

Pulau Panjang terletak di sebelah barat pantai Kota Jepara memiliki luas wilayah teritorial 30 Ha dan dimanfaatan sebagai wisata pulau, wisata ziarah, dan lokasi penangkapan ikan. Kombinasi kondisi gelombang ekstrim dan air pasang mengakibatkan tekanan kuat di pesisir Pulau Panjang sehingga menimbulkan kerusakan pada fasilitas wisata. Berdasarkan hal tersebut, diperlukan adanya analisis mengenai karakteristik penjalaran gelombang laut untuk menunjang segala jenis kegiatan masyarakat. Analisis penjalaran gelombang dilakukan melalui pendekatan pemodelan numerik hidrodinamika dua dimensi (two-dimensional hydrodynamic model). Data primer yang digunakan adalah data pengukuran langsung nilai gelombang menggunakan instrument Acoustic Doppler Current Profiler dan pengukuran langsung data batimetri menggunakan instrument single-beam echosounder. Data sekunder meliputi data angin (1999 – 2019) yang didapatkan dari portal unduh data di www.ogimet.com, data pasang surut BMKG dan data batimetri dari Badan Informasi Geospasial. Tinggi gelombang signifikan (Hs) dan periode signifikan (Ts) didapatkan dari konversi data angin menjadi nilai Hs dan Ts dengan metode DNS. Nilai Hs dan Ts maksimal setiap arah mata angin mmenjadi input perhitungan model hidrdodinamika. Hasil spasial penjalaran gelombang tertinggi terjadi pada arah datang gelombang dari arah timur laut, tenggara dan barat. Penjalaran gelombang di Pulau Panjang menciptakan daerah terlindung di sisi seberang dari arah datang gelombang dan saat gelombang endekati pantai penjalaran gelombang mengikuti kontur garis pantai diikuti dengan melemahnya kecepatan rambat gelombang. Panjang Island is located on the west coast of Jepara City and has a territorial area of 30 hectares and is used as island tourism, pilgrimage tours, and fishing locations. The combination of extreme wave conditions and high tide resulted in strong force on the coast of Panjang Island causing damage to tourist facilities. Based on this, it is necessary to have an characteristics analysis of the sea waves propagation to support all types of community activities. Analysis of the propagation of the waves was carried out using a two-dimensional hydrodynamic model approach. The primary data used are direct measurement data of wave values using the Acoustic Doppler Current Profiler instrument and direct measurement of bathymetric data using a single-beam echosounder instrument. Secondary data includes wind data (1999 - 2019) obtained from the data download portal at www.ogimet.com, BMKG tidal data and bathymetry data from the Geospatial Information Agency. Significant wave height (Hs) and significant period (Ts) are obtained from the conversion of wind data into Hs and Ts values using the DNS method. The maximum Hs and Ts values for each cardinal direction are the input for calculating the hydrodynamic model. The highest spatial results of wave propagation occur in the coming direction of waves from the northeast, southeast and west. The wave propagation in Panjang Island creates a protected area on the opposite side from the direction of the waves coming and when the waves approach the coast the propagation of the waves follow the contours of the coastline followed by a weakening of the wave propagation speed.

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Numerical study of Love wave propagation

Geophysics ◽

10.1190/1.1441515 ◽

1983 ◽

Vol 48 (7) ◽

pp. 833-853 ◽

Cited By ~ 14

Author(s):

K. R. Kelly

Keyword(s):

Numerical Modeling ◽

Wave Propagation ◽

Love Wave ◽

Fourier Transforms ◽

Narrow Band ◽

Numerical Study ◽

Two Dimensional ◽

Band Pass ◽

The Waves ◽

Insight Into

Love wave propagation is studied by investigating numerical modeling results for several examples of geologic interest. The modal characteristics of the results are clarified by the use of narrow band‐pass filters and two‐dimensional Fourier transforms in range and time. Such processing makes it possible to study changes in phase and group velocity for the various modes and to locate points of reflection. This permits one to gain insight into changes in the physical properties of the surface channel supporting the waves.

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Kajian Pola Arus Laut dan Distribusi Sedimen Di Perairan Pantai Muara Kamal Jakarta Utara

Jurnal Rekayasa Hijau ◽

10.26760/jrh.v1i1.1335 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Permana Ari Soerjawo ◽

Thonas Indra Maryanto

Keyword(s):

Current Velocity ◽

High Tide ◽

Clay Fraction ◽

Secondary Data ◽

Acoustic Doppler Current Profiler ◽

Google Earth ◽

Ocean Current ◽

Primary Data ◽

Sediment Distribution ◽

Current Profiler

ABSTRAKPola arus laut dan distribusi sedimen merupakan proses dinamika di suatu perairan yang mempunyai karakteristik berbeda-beda, sehingga berpengaruh terhadap pembentukan geomorfologi pantai di seluruh dunia. Penelitian ini bertujuan untuk mengetahui pola arus dan sedimen di perairan Pantai Muara Kamal Jakarta Utara di tahun 2012. Data yang digunakan merupakan data primer dan data sekunder, data primer meliputi data arus yang didapat dari pemasangan ADCP(Acoustic Doppler Current Profiler), data pasang surut dan sedimen perairan yang diambil dengan sedimen grab. Data sekunder berupa peta LPI (Lingkungan Pantai Indonesia) tahun 2000 skala 1:50.000 dari BIG (Badan Informasi Geospasial) dan citra satelit Google Earth tahun 2009. Hasil penelitian menunjukan bahwa kecepatan arus yang paling besar terdapat pada lapisan permukaan dengan kecepatan 0,242 m/s kearah barat daya (207,8o), kecepatan arus terkecil terdapat pada lapisan dasar yaitu 0,141 m/s kearah barat daya (207o). Hasil simulasi model hidrodinamika 2D, menunjukkan bahwa pada saat pasang arus laut mengarah ke daratan (selatan) dan pada saat surut arus laut mengarah ke laut lepas (barat laut). Berdasarkan kandungan ukuran butir sedimen di perairan Pantai Muara Kamal Jakarta Utara adalah pasir (64.98 - 72.15%) fraksi pasir tertinggi distasiun B(belakang geotekstil), lanau (24.56 - 29.36%) fraksi lanau tertinggi di stasiun C (depan geotekstil) dan Lempung (1.64 – 5.64%) fraksi lempung tertinggi di stasiun C (depan geotekstil). Kata kunci: Arus, Pantai Muara Kamal, Sedimen, model hidrodinamika 2D ABSTRACTOcean current and sediment distribution are the dynamic process that have different charactheristic and therefore influenced beach geomorfophology around the world. This research aims to understand both ocean current and sediment pattern in Muara Kamal North Jakarta in 2012. This research used primary and secondary data, primary data were consisted of current data from ADCP (Acoustic Doppler Current Profiler), tidal data and bottom sediment samples. Secondary data involved of Indonesia Coastline Environmental map of year 2000 with scale 1:50.000 from Geospatial information Agency and a satellite data from Google earth of year 2009. The results showed that greatest ocean current velocity contained in the surface layer at a speed of 0,242 m/s with to southwest direction (207.8o), the smallest current velocity was in bottom layer is 0.141 m/s with southwest directiont (207o). Based on 2D hydrodynamic model simulation indicated that when high tide ocean current was flowed to the mainland (south) when low tide the current was flowed to the open sea direction. Based on the content grain size of the sediment, the studi area consisted of sand (64.98 - 72.15%) the highest sand fraction at station B(rare of geotextile) , silt (24.56 - 29.36%) the highest silt fraction at station C (front of geotextile) andclay (1.64 – 5.64%) the highest clay fraction at station C(front of geotextile) Key Words: Current, Muara Kamal Shoreline, Sediment, 2D hydrodynamics model

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Wave Propagation Feature in Two-Dimensional Periodic Beam Lattices with Local Resonance by Numerical Method and Analytical Homogenization Approach

International Journal of Applied Mechanics ◽

10.1142/s1758825118500424 ◽

2018 ◽

Vol 10 (04) ◽

pp. 1850042 ◽

Cited By ~ 1

Author(s):

C. W. Zhou ◽

X. K. Sun ◽

J. P. Lainé ◽

M. N. Ichchou ◽

A. Zine ◽

...

Keyword(s):

Wave Propagation ◽

Homogenization Method ◽

Two Dimensional ◽

Local Resonance ◽

Homogenization Approach ◽

Discrete Media ◽

The Waves ◽

Locking Phenomena ◽

Analytical Homogenization ◽

Propagation Feature

In this paper, the analytical homogenization method of Periodic Discrete Media (HPDM) and the numerical Condensed Wave Finite Element Method (CWFEM) are employed to study the wave propagation in two-dimensional periodic beam lattices. The validity of the HPDM is re-evaluated using the wave propagation feature identified by the CWFEM. Particular attention is paid to the polarization direction of the waves. The wave propagation in two directions is investigated while characteristic wave propagation features such as local resonance, veering and locking phenomena are observed. Complementary results are deduced from the two methods.

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Efficient Geometric Disassembly of Multiple Components from an Assembly Using Wave Propagation

Journal of Mechanical Design ◽

10.1115/1.533567 ◽

2000 ◽

Vol 122 (2) ◽

pp. 179-184 ◽

Cited By ~ 24

Author(s):

Hari Srinivasan ◽

Rajit Gadh

Keyword(s):

Wave Propagation ◽

Three Dimensional ◽

Computation Time ◽

Two Dimensional ◽

New Approach ◽

Multiple Components ◽

Disassembly Sequence ◽

Minimal Component ◽

Selective Disassembly ◽

The Waves

This paper analyzes the problem of disassembling multiple selected components from an assembly, defined as selective disassembly, and presents algorithms for efficient disassembly analysis of geometric models. Applications for selective disassembly include assembling, maintenance and recycling. A new approach called ‘Disassembly Wave Propagation’ is proposed to determine a selective disassembly sequence with minimal component removals from an assembly. This approach defines: (i) disassembly waves to topologically arrange the components denoting the disassembly order and (ii) intersection events between the waves to determine the selective disassembly sequences. In order to evaluate a minimal removal sequence in a feasible computation time, algorithms are proposed that prioritize and process the intersection events based on the order in which they occurred. The proposed algorithms analyze selective disassembly from the geometric perspective and are applicable for both two-dimensional and three-dimensional product assemblies. [S1050-0472(00)01402-1]

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