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In this paper, we demonstrate physical science training and its application for primary and secondary school teachers in Oelnasi Village, Kupang Regency, East Nusa Tenggara Province. Oelnasi Village is a new potential area in the development of science and technology (IPTEK) due to the availability of a national astronomical observation center in this area. The development of science and technology requires the development and improvement of knowledge related to natural phenomena. To realize this, we, Physics Lecturers at the Physics Study Program of the Faculty of Science and Technology, University of Nusa Cendana, carry out an activity to increase knowledge for elementary and junior high school teachers in Oelnasi village and around through physics training and its application. in community service activities. This activity is carried out in the form of a workshop session where the speaker provides the latest physics and development materials followed by a question and answer session. This activity can open insights and increase knowledge in the field of physics and its application for teachers.

This paper presents spatial distribution, temporal seismotectonics, and return period of earthquake in East Nusa Tenggara Province, Indonesia, using earthquake data and Maximum Likelihood methods. The data used are ISC, USGS/NEIC, and Indonesian Meteorology, Climatology and Geophysics Agency (IMCGA) earthquake catalog data for the period of 1918 to 2015. The results show that the a-value ranges from 5.0 to 8.5 and b-value ranges from 0.6 to 1.3. The pattern of spatial distribution of b-value is relatively low corresponding to the low of a-value, which means the high level of stress of rock in the area. The fractal dimension shows that the D value ranges from 1.384 to 1.874. The earthquake that occurred in East Nusa Tenggara Province was dominated by a small magnitude with great seismicity and the fastest return period is in Alor and Timor islands which is 44 days.

Telah dilakukan penelitian tentang pendugaan jenis perlapisan batuan pada wilayah longsoran Desa Tolnaku, Kecamatan Fatuleu, Kabupaten Kupang. Penelitian ini bertujuan untuk mengidentifikasi jenis perlapisan batuan dan memperkirakan kedalaman setiap perlapisan batuan bawah permukaan di sekitar wilayah longsoran tersebut. Pengambilan data dilakukan menggunakan metode geolistrik resistivitas konfigurasi Schlumberger dan analisis data penelitian menggunakan software Res2Dinv untuk mendapatkan nilai resistivitas sebenarnya. Berdasarkan hasil penelitian, jenis batuan di lokasi penelitian terdiri atas batuan lempung (clay) dengan nilai resistivitas 1,1 – 27,60 pada kedalaman 5 – 105 m, batuan alluvium dengan nilai resistivitas 10,0 – 79,4 pada kedalaman 5 – 105 m, dan gamping (limestone) dengan nilai resistivitas 50,0 – 1.817 pada kedalaman 27 – 105 m. Kata Kunci: Geolistrik Resistivitas, Schlumberger, Res2Dinv Abstract A study on the estimation of underground rock petterns in Tolnaku village Kupang Regency has been conducted. The study aims to identify types of rock layers and to estimate the deph of each layer. Data was taken using geoelectricity method with Schlumberger configurasi while the data analysis was performed using Res2Dinv to obtain the real resistivity value. From the results, rocks foud in the research location are clay with resistivity being 1.1 – 27.6 (between 5 – 105 m), alluvium with resistivity being 10.0 – 79.4 (between 5 – 105 m), and limestone with resistivity being 50.0 - 1.817 (between 25–105 m). Key words: Geoelectric resistivity, Schlimberger, Res2Dinv.

Penelitian menggunakan metode HVSR (Horizontal to Vertical Spectral Ratio) telah dilakukan untuk memetakan daerah yang rawan terhadap gempa bumi di Desa Bitobe. Tujuan dari penelitian ini adalah mengetahui nilai periode dominan tanah dan percepatan tanah maksimum, serta untuk membuat peta PGA dan juga peta Mikrozonasi. Pengambilan data dilakukan pada 45 titik dengan jarak antar titik ± 250 m dari titik satu ke titik lainnya dengan waktu perekaman selama ± 20 menit menggunakan TDS tipe 303S. Data yang diperoleh diolah menggunakan software Datapro, Geopsy, Surfer 13, dan Google Earth. Hasil pengolahan data diperoleh nilai frekuensi dominan (). Parameter ini digunakan untuk meghitung nilai PGA menggunakan persamaan empiris Kanai dengan data katalog gempa bumi dari tahun 1966-2016. Metode Mc.Guirre dan Esteva hanya menggunakan data katalog gempa saja dalam menghitung PGA. Berdasarkan hasil penelitian, didapatkan bahwa nilai frekuensi dominan berkisar antara 0,273 Hz – 17,887 Hz. Nilai percepatan tanah maksimum berdasarkan persamaan empiris Kanai berkisar antara 32,319 gal – 261,178 gal, Mc.Guirre berkisar antara 128,215 gal – 134,862 gal dan Esteva berkisar antara 147,359 gal – 156,007 gal. Hasil dari ketiga persamaan ini memiliki perbedaan dengan peta hazard gempa Indonesia. Kata kunci: HVSR, Mikrozonasi, Kanai, Mc.Guirre, Esteva, Bitobe ABSTRACT The research using HVSR (Horizontal to Vertical Spectral Ratio) has been carried out to map the disturb areas to earthquakes in Bitobe village. The aims of this research are to determine the values of soil dominant frequency and the peak ground acceleration than make PGA map and also microzonation map. Data were collected at 45 points with the distance between points ± 250 meters from one point to the other with ± 20 minutes of recording time used TDS 303S type. The data were processed using software Datapro, Geopsy, Surfer 13, and Google Earth. The result of data processing was dominant frequency value (). This parameter was used to calculate the peak ground acceleration with Kanai empirical equations. The earthquakes catalog data were used from 1966-2016. Mc.Guirre and Esteva method only used the earthquakes catalog data to calculated the PGA. According to this research, it was obtained that the values of the dominant frequency was about 0,273 Hz – 17,887 Hz. The values of peak ground acceleration based on Kanai empirical equations about 32,319 gal – 261,178 gal, Mc.Guirre about 128,215 gal – 134,862 gal and Esteva about 147,359 gal – 156,007 gal. The result of this third equations have different with the earthquakes hazard map of Indonesia. Key Words: HVSR, Microzonation, Kanai, Mc.Guirre, Esteva, Bitobe

Telah dilakukan penelitian mikrozonasi seismik di desa Nunkurus Kecamatan Kupang Timur Kabupaten Kupang. Penelitian ini bertujuan untuk mengetahui nilai frekuensi dominan tanah, nilai ampifikasi, indeks kerentanan tanah dan percepatan tanah serta membuat peta indeks kerentanan tanah dan peta. Berdasarkan hasil penelitian diperoleh nilai frekuensi dominan tanah berkisar antara 0.293 Hz – 18.41 Hz, nilai amplifikasi berkisar antara 1,68–8,52, nilai indeks kerentanan seismik berkisar antara 0,3285 –179,23556 dan nilai PGA berkisar antara 107,77488 gal-218,62941 gal sehingga dapat dikatakan bahwa daerah penelitian berada dalam kawasan yang cukup aman karena hanya sebagian titik saja yang memiliki nilai frekuensi, nilai amplifikasi, nilai indeks kerentanan dan nilai PGA yang besar. Kata kunci : Mikrozonasi, HVSR, Nunkurus ABSTRACT The research about seismic microzonation in Nunkurus village, sub-district of east Kupang, district of Kupang has been done. The aims of this research are to determine the values of soil dominant frequency, magnitude of amplification, seismic vulnerability index, the peak ground acceleration and to make seismic vulnerability index map and PGA map. The results showed that the values of the the values of the dominant frequency was about 0,293 Hz – 18,41 Hz, the amplification about 1,68 – 8,52. Meanwhile, the index of vulnerability was found to be 0,32853 – 179,23556 and peak ground acceleration values about 107,77488 gal - 218,62941 gal so it can be said that the area of ​​research is safe enough because only a single point that has the frequency value, the value of amplification, the index value of vulnerability and PGA great value. Keywords : Microzonation, HVSR, Nunkurus

Telah dilakukan penelitian tentang mikrozonasi seismik dengan metode HVSR di Desa Lili Kecamatan Fatuleu Kabupaten Kupang. Tujuan dari penelitian ini adalah mengetahui nilai frekuensi dominan tanah, amplifikasi, indeks kerentanan seismik dan percepatan tanah maksimum. Penelitian dilakukan dengan menggunakan TDS tipe 303 dengan frekuensi natural 0,2Hz-20Hz. Berdasarkan hasil penelitian, didapatkan bahwa nilai frekuensi dominan berkisar antara 0,279 Hz-17,210Hz, nilai amplifikasi berkisar antara 1,802-10,240 dan nilai indeks kerentanan seismik berkisar antara 0,422-421,167. Nilai percepatan tanah maksimum berkisar antara 160,769 gal – 279,316 gal dengan tingkat resiko besar dua dan tingkat resiko besar tiga. Kata kunci: Mikrozonasi, HVSR, Lili ABSTRACT The research about seismik microzonation using HVSR methods in Lili village, sub-district of Fatuleu, district of Kupang has been done. The aims of this research are to determine the values of soil dominant frequency, magnitude of amplification, seismik vulnerability index, and the peak ground acceleration. This research used TDS 303S type with0,2Hz-20Hz of natural frequency. According to this research, it was obtained that the values of the dominant frequency was about 0,279Hz-17,210Hz, the amplification values were found to be 1,802-10,240 and the index of vulnerability has values about 0,422-421,167. The peak ground acceleration values about 160,769 gal – 279,316 gal with great risk level two and great risk level three. Keywords: microzonation, HVSR, Lili

Telah dilakukan penelitian tentang analisis spektral dan penentuan hiposenter gempa gunung Lewotobi dan gunung Egon serta hubungannya dengan gempabumi tektonik di daerah sekitarnya. Tujuan penelitian adalah menentukan karakteristik spektral, hiposenter gempa, b-value, serta menyelidiki hubungan antara gempa vulkanik dan gempa tektonik yang terjadi di daerah sekitar. Data kegempaan vulkanik diperoleh dari Pos PGA Lewotobi dan Pos PGA Egon dari tanggal 1 Januari sampai 31 januari 2016. Untuk data kegempaan tektonik diperoleh dari katalog international seismology center (ISC) dan U.S. Geological Survey National Earquake Information Center (USGS/NEIC) dari tahun 1965-2016. Analisis spektral dari gempa yang terekam di seismograf pos PGA digunakan untuk mendapatkan frekuensi dominan, untuk gempa vulkanik dalam, vulkanik dangkal dan tektonik lokal pada gunung Lewotobi digunakan untuk menentukan hiposenter gempa gunung Lewotobi. Untuk data gempabumi tektonik dilakukan analisis b-value. Hasil menunjukan bahwa frekuensi dominan setiap gempa yang terjadi pada gunung Lewotobi: gempa vulkanik dalam 10-13 Hz, vukanik dangkal 4,87-13,6 Hz, tornillo 1,69-16,8 hz, tremor harmonik 1,72-2 Hz, tektonik jauh1,041 – 5,282 Hz, tektonik lokal 1,80-2,79 Hz, hembusan 2,54-7,53 hz, low frekuensi 0,72-1,97 hz. Untuk gempa yang terjadi di gunung Egon: gempa vulkanik dalam 10-13,0 Hz, vulkanik dangkal 10-12,1 Hz, tremor harmonik 11-20,9 Hz, swarm 11-12,3 Hz, tektonik lokal 11,9-12,6 Hz, tektonik jauh 2,62-12,6 Hz, hembusan 4,88-12,8 Hz, low frekuensi 0,47-3,17 Hz, tornillo 12-12,6 Hz. Hiposenter gempa vulkanik banyak terjadi di gunung Lewotobi laki-laki dan tektonik lokal di baratdaya gunung Lewotobi. Nilai b-value yang diperoleh 1,12 ± 0,18. Dari hasil analisis tidak ditemukan korelasi langsung antara aktivitas vulkanik dan tektonik Katakunci: Lewotobi, Egon, Vulkanik, Tektonik, b-Value. Abstract Has done research on spectral analysis and determination of hypocenter Lewotobi and Egon and its relation to tectonic earthquakes in the surrounding area. The puporse of the research was to determine the spectral characteristics, hypocenter, b-value, as well as investigating the relationship between volcanic earthquake and tectonic earthquake that occurred in the area around. The data of volcanic seismicity obtained from the Lewotobi and Egon PGA Post on January 1st until January 31st 2016. And the data of tectonic seismicity obtained from International Seismicity Center (ISC) catalog and U.S. Geological Survey National Earthquake Information Center (USGS/NEIC) on 1965-2016. Spectral analysis of earthquake that recorded on a seismograph in PGA post used to get dominant frequency, the deep volcanic earthquake, shallow volcanic earthquake, and local tectonic on Lewotobi used to determine hypocenter of earthquake of Lewotobi mount. For the data of tectonic earthquake obtained by doing analysis b-value. The results show that dominant frequency each earthquake that occurred on Lewotobi: deep volcanic earthquake 10-13 Hz, shallow volcanic 4,87-13,6 Hz, tornillo 1,69-16,8 Hz, harmonic tremor 1,72-2 Hz, far tectonic 1,041-5,282 Hz, local tectonic 1,80-2,79 Hz, blowing 2,54-7,53 Hz, low frequency 0,72-1,97 Hz. For earthquake on Egon: deep volcanic earthquake 10-13,0 Hz, shallow volcanic 10-12,1 Hz,9 harmonic tremor 11-20,9 Hz, swarm 11-12,3 Hz, local tectonic 11,9-12,6 Hz, far tectonic 2,62-12,6 Hz, blowing 4,88-12,8 Hz, low frequency 0,47-3,17 Hz, tornillo 12-12,6 Hz. Volcanic hypocenter erthquakemostly occurred in Lewotobilaki-laki and local tectonic occurred on southwest of mount Lewotobi. The value of b-value obtained was 1,12 ± 0,18. From the result of analysis not founded a direct correlation of volcanic and tectonic activity. Keywords: Lewotobi, Egon, Volcanic, Tectonic, b-value

We report the first measurements of radio frequency spectrum occupancy performed at sites aimed to host the future radio astronomy observatory in Indonesia. The survey is intended to obtain the radio frequency interference (RFI) environment in a spectral range from low frequency 10 MHz up to 8 GHz. The measurements permit the identification of the spectral occupancy over those selected sites in reference to the allocated radio spectrum in Indonesia. The sites are in close proximity to Australia, the future host of Square Kilometre Array (SKA) at low frequency. Therefore, the survey was deliberately made to approximately adhere the SKA protocol for RFI measurements, but with lower sensitivity. The RFI environment at Bosscha Observatory in Lembang was also measured for comparison. Within the sensitivity limit of the measurement equipment, it is found that a location called Fatumonas in the surrounding of Mount Timau in West Timor has very low level of RFI, with a total spectrum occupancy in this measured frequency range being about 1 %, mostly found at low frequency below 20 MHz. More detailed measurements as well as a strategy for a radio quiet zone must be implemented in the near future.

International audience; La mémoire sert à oublier. Il semble qu’à Locquirec plus personne ne se rappelle d’un bateau échoué sur la plage des Sables-Blancs dans la nuit du 8 au 9 août 1939, et de la curiosité qu’il suscita alors. À Jersey non plus, on ne se rappelle pas d’une caisse de tracts autonomistes perdue par ce bateau et retrouvée par un pêcheur de l’île. Le nom même du bateau le Gwalarn ne semble pas avoir laissé de trace dans les archives maritimes1. L’affaire du Gwalarn, du débarquement d’armes et tracts organisé par Célestin Lainé s’est diluée dans l’effervescence des semaines précédant la Seconde Guerre mondiale. Peu de gens la connaissent. Ce n’est pas faute d’avoir été relatée : on ne compte plus les récits du mystérieux débarquement. L’histoire sert à rêver. Mais au regard de nouvelles archives qui aident à préciser le déroulement de l’affaire, l’étude des récits qui en ont été faits permet de mettre à jour quelques mécanismes à l’oeuvre dans l’historiographie du mouvement breton.