No abstract

Kedalaman relatif perairan dangkal dapat diperoleh melalui Digital Elevation Model (DEM). Seiring berkembangnya sains, banyak metode dikembangkan untuk memperoleh nilai kedalaman relatif salah satunya dengan mengolah citra Sentinel-2 menggunakan algoritma Van Hengel and Spitzer. Penulis bertujuan untuk membandingkan nilai kedalaman relatif yang didapatkan dari pengolahan citra Sentinel-2 menggunakan algoritma Van Hengel and Spitzer dengan kedalaman relatif yang didapatkan melalui DEM. Data yang dibutuhkan pada penelitian ini adalah citra Sentinel-2 level 1C yang telah ter orthorektifikasi diunduh dari laman Earth Explorer dan DEM yang diunduh dari laman Tanah Air. Citra Sentinel-2 kemudian dikoreksi secara atmosferik dan radiometrik untuk mendapatkan nilai radiannya yang kemudian diolah dengan algoritma Van Hengel and Spitzer. Titik sampel disebar dengan interval 25 meter sepanjang sungai Brantas Kabupaten Jombang. Penelitian ini hanya membandingkan perhitungan secara komputasi sehingga tidak dilakukan validasi lapangan. Hasil dari pengolahan citra Sentinel-2 dengan algoritma Van Hengel and Spitzer memberikan rata-rata kedalaman relatif sebesar 16,35m dan rata-rata kedalaman relatif DEM yaitu sebesar 17,98m. Hasil perhitungan statistik menunjukkan nilai koefisien determinasi kedalaman relatif citra Sentinel-2 yang diolah menggunakan algoritma Van Hengel and Spitzer dengan DEM adalah sebesar 6,52%. Korelasi yang rendah tersebut diakibatkan tingginya kandungan sedimen dalam kolom air Sungai Brantas sehingga menimbulkan bias pada citra.

One of the stages in the topographical mapping work is the measurement of the horizontal control framework, which is currently almost all done using GNSS satellite technology. The online post-processing services provided by the Indonesian Geospatial Information Agency (BIG) are called xpos-InaCORS. Using this service, measurements are possible using only 1 GNSS receiver can be used for measurement and obtained of the mapping control framework. This research was conducted to determine the accuracy of the online post-processing method by xpos-InaCORS BIG when used as a control point for the mapping of the route of the channel or road which tends to be elongated with a 3rd order (SNI 19-6724-2002). The coordinates of the results of the online processing calculation are compared with the results of the static differential method, which is calculated using commercial software (Leica Infinity). The results showed that at this location, observations for 15 minutes on each benchmark were able to produce an accuracy of 1 centimeter, and to comply with the qualifications of order 3rd SNI, observations must be a minimum duration of 75 minutes. The cost of observation on the online post-processing method requires 60% of the static differential. Observation at 75 minutes resulted in an average accuracy of northing (N) = 15mm and easting (E) = 8mm.

Electricity plays a critical role in telecommunication business. Information transmission service infrastructure such as base transceiver stations (BTSes), base station controllers, and mobile switching centers must not lose electricity supply. Therefore, telecommunication enterprises have gensets as backup power supplies. However, these gensets are usually located at a point remote from the BTS, making it difficult for operators to monitor and operate them. This study designs an Arduino and Ethernet Shield remote monitoring and operating system for BTS gensets by utilizing a TCP/IP technology as communication protocols. Gensets are monitored using the likes of voltage sensor, current sensor and fuel sensor.