Judul: Behavior of Komodo Dragon  in Rinca Island, Komodo National Park East Nusa Tenggara During the Covid-19 Pandemic
Abstrak: Pandemi Covid-19 mengakibatkan pemerintah menutup kegiatan wisata. Penelitian ini membandingkan perilaku komodo di kawasan di lokasi wisata Loh Buaya dan lokasi non wisata di Loh Baru SPTN I Pulau Rinca, setelah pembukaan kawasan yaitu 21 Juni hingga 28 September 2020. Pengamatan perilaku dilakukan terhadap 9 individu komodo (3 jantan dewasa, 3 betina dewasa, dan 3 remaja) pada masing-masing lokasi. Pengamatan perilaku menggunakan metode focal animal sampling dari jam 06.00 – 18.00 WITA dengan waktu pengamatan 30 jam per individu. Hasil penelitian menunjukkan terdapat perilaku agonistik, lokomosi, investigatif, ingestif, pemeliharaan dan agresif. Perilaku agresif kepada manusia, yang tidak ditemukan pada penelitian sebelumnya, terlihat pada 3 individu komodo dewasa. Penggunaan ruang oleh komodo menunjukkan bahwa komodo jantan lebih .banyak menggunakan ruang non alami pada kedua lokasi. Komodo betina lebih banyak menggunakan ruang alami pada lokasi non wisata dibandingkan pada lokasi wisata. Komodo remaja lebih banyak menggunakan ruang alami di kedua lokasi., Tourism activities in Komodo National Park have been halted due to goverment policies relating to the Covid-19 pandemic. This study compared the behavior of komodo dragons after opening at tourist’s site on Loh Buaya and non-tourist’s sites on Loh Baru SPTN I Rinca Island from June 21st- September 28th, 2020. Behavior observations were made on nine individual komodo dragons at each location, which include three adult males, three adult females, and three juveniles. Focal animal sampling approach was used for observation from 06.00 – 18.00 WITA, with a total observation duration of 30 hours for each individual. Komodo showed agonistic, locomotion, investigative, ingestive, maintenance, and aggresive behaviors. Aggresive behavior to human, which had not bee seen previously, was seen in three adult komodo dragons: two at tourism locations and one at non-tourism area. The use of space by komodo dragons shows that male use more non-natural space at both locations, female use more natural space at non-tourist locations than at tourism sites, while juvenile use more natural space in both locations.
Keyword: dampak penutupan kawasan, focal animal sampling, perilaku agresif, perilaku komodo, pandemi covid-19

Judul: Behavior of Komodo Dragon  in Rinca Island, Komodo National Park East Nusa Tenggara During the Covid-19 Pandemic
Abstrak: Pandemi Covid-19 mengakibatkan pemerintah menutup kegiatan wisata. Penelitian ini membandingkan perilaku komodo di kawasan di lokasi wisata Loh Buaya dan lokasi non wisata di Loh Baru SPTN I Pulau Rinca, setelah pembukaan kawasan yaitu 21 Juni hingga 28 September 2020. Pengamatan perilaku dilakukan terhadap 9 individu komodo (3 jantan dewasa, 3 betina dewasa, dan 3 remaja) pada masing-masing lokasi. Pengamatan perilaku menggunakan metode focal animal sampling dari jam 06.00 – 18.00 WITA dengan waktu pengamatan 30 jam per individu. Hasil penelitian menunjukkan terdapat perilaku agonistik, lokomosi, investigatif, ingestif, pemeliharaan dan agresif. Perilaku agresif kepada manusia, yang tidak ditemukan pada penelitian sebelumnya, terlihat pada 3 individu komodo dewasa. Penggunaan ruang oleh komodo menunjukkan bahwa komodo jantan lebih .banyak menggunakan ruang non alami pada kedua lokasi. Komodo betina lebih banyak menggunakan ruang alami pada lokasi non wisata dibandingkan pada lokasi wisata. Komodo remaja lebih banyak menggunakan ruang alami di kedua lokasi., Tourism activities in Komodo National Park have been halted due to goverment policies relating to the Covid-19 pandemic. This study compared the behavior of komodo dragons after opening at tourist’s site on Loh Buaya and non-tourist’s sites on Loh Baru SPTN I Rinca Island from June 21st- September 28th, 2020. Behavior observations were made on nine individual komodo dragons at each location, which include three adult males, three adult females, and three juveniles. Focal animal sampling approach was used for observation from 06.00 – 18.00 WITA, with a total observation duration of 30 hours for each individual. Komodo showed agonistic, locomotion, investigative, ingestive, maintenance, and aggresive behaviors. Aggresive behavior to human, which had not bee seen previously, was seen in three adult komodo dragons: two at tourism locations and one at non-tourism area. The use of space by komodo dragons shows that male use more non-natural space at both locations, female use more natural space at non-tourist locations than at tourism sites, while juvenile use more natural space in both locations.
Keyword: dampak penutupan kawasan, focal animal sampling, perilaku agresif, perilaku komodo, pandemi covid-19

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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