Kebertahanan Kawasan Perkampungan Pedamaran Semarang

Setiap kota besar biasanya mempunyai suatu kawasan yang masih mempertahankan kebudayaannya sebelumnya, baik fisik berupa bentuk bangunan yang masih tradisional maupun non fisik yaitu kegiatan-kegiatan yang sejak zaman dahulu dilakukan masih dilakukan. Kawasan tersebut sering disebut dengan kampung. Kampung berbeda dengan desa, salah satunya ialah lokasi desa yang berada di luar kota sedangkan kampung berada di dalam kota. Oleh karena itu, kampung memiliki masalah yang lebih pelik daripada desa. Secara keseluruhan, permasalahan yang dihadapi oleh Kawasan Perkampungan Pedamaran Semarang ialah banjir, drainase yang buruk, padat akan bangunan, kumuh dan tingginya angka kemiskinan. Masalah utama sendiri ialah masalah kemiskinan dan banjir. Namun, walaupun dihadang masalah demikian, kampung ini masih eksis. Tujuan dari penelitian ini ialah untuk mengetahui apa yang membuat Kampung Pedamaran di Kota Semarang bertahan hingga saat ini. Adapun metode yang digunakan ialah kualitatif desktriptif, dengan mengkaji karakteristik kampong melalui konsep elemen perancangan kota, mengkaji aspek fisik dan aspek non fisik kawasan. Pengumpulan data difokuskan kepada observasi lingkungan dan wawancara terhadap narasumber yang dianggap mengerti benar keadaan Kampung Pedamaran. Berdasarkan proses penelitian yang telah dilakukan sebelumnya maka dapat dilihat bahwa yang membuat kampung dapat bertahan dari berbagai permasalahan terutama terhadap banjir dan kemiskinan adalah oleh karena keadaan sosial kampung yang baik, dan karena kemudahan dalam mencari nafkah

Elevated CO2 emissions during magmatic-hydrothermal degassing at Awu Volcano, Sangihe Arc, Indonesia

Awu is a remote and little known active volcano of Indonesia located in the northern part of Molucca Sea. It is the northernmost active volcano of the Sangihe arc with 18 eruptions in less than 4 centuries, causing a cumulative death toll of 11,048. Two of these eruptions were classified with a Volcanic Explosivity Index (VEI) of 4. Since 2004, a lava dome has occupied the centre of Awu crater, channelling the fumarolic gas output along the crater wall. A combined Differential Optical Absorption Spectroscopy (DOAS) and Multi-component Gas Analyzer System (Multi-GAS) study highlight a relatively small SO2 flux (13 t/d) sustained by mixed magmatic–hydrothermal emissions made-up of 82 mol.% H2O, 15 mol.% CO2, 2.55 mol.% total S (ST) and 0.02 mol.% H2. The CO2 emission budget, as observed during a short observation period in 2015, corresponds to a daily contribution to the atmosphere of 2600 t/d, representing 1% of the global CO2 emission budget from volcanoes. The gas CO2/ST ratio of 3.7 to 7.9 is at the upper limit of the Indonesian gas range, which is ascribed to (i) some extent of S loss during hydrothermal processing, and perhaps (ii) a C-rich signature of the feeding magmatic gas phase. The source of this high CO2 signature and flux is yet to be fully understood; however, given the peculiar geodynamic context of the region, dominated by the arc-to-arc collision, this may result from either the prolonged heating of the slab and consequent production of carbon-rich fluids, or the recycling of crustal carbon

High‐resolution InSAR reveals localised pre‐eruptive deformation inside the crater of Agung volcano, Indonesia.

During a volcanic crisis, high-rate, localized deformation can indicate magma close to the surface, with important implications for eruption forecasting. However, only a few such examples have been reported, because frequent, dense monitoring is needed. High-resolution Synthetic Aperture Radar (SAR) is capable of achieving 15 cm of line-of-sight shortening occurred over a 400-by-400 m area on the crater floor in September-October 2017, accompanying a deep seismic swarm and flank dyke intrusion. We attribute the deformation to the pressurization of a shallow (<200 m deep) hydrothermal system by the injection of magmatic gases and fluids. We also observe a second pulse of intra-crater deformation of 3–5 cm within 4 days to 11 hr prior to the first phreatomagmatic eruption, which is consistent with interaction between the hydrothermal system and the ascending magma. This phreatomagmatic eruption created the central pathway used during the final stages of magma ascent. Our observations have important implications for understanding unrest and eruption forecasting, and demonstrate the potential of monitoring with high-resolution SAR

Anatomy of phreatic eruptions

This study investigates phreatic eruptions at two similar volcanoes, Kawah Ijen (Indonesia) and White Island (New Zealand). By carefully processing broadband seismic signals, we reveal seismic signatures and characteristics of these eruptions. At both volcanoes, the phreatic eruptions are initiated by a very-long-period (VLP) seismic event located at shallow depths between 700 and 900 m below the crater region, and may be triggered by excitation of gas trapped behind a ductile magma carapace. The shallow hydrothermal systems respond in different ways. At Kawah Ijen, the stress change induced by VLPs directly triggers an eigenoscillation of the hyperacidic lake. This so-called seiche is characterized by long-lasting, long-period oscillations with frequencies governed by the dimensions of the crater lake. A progressive lateral rupture of a seal below the crater lake and/or fluids migrating toward the surface is seismically recorded ∼ 15 min later as high-frequency bursts superimposed to tilt signals. At White Island, the hydrothermal system later (∼ 25 min) responds by radiating harmonic tremor at a fixed location that could be generated through eddy-shedding. These seismic signals shed light on several aspects of phreatic eruptions, their generation and timeline. They are mostly recorded at periods longer than tens of seconds further emphasizing the need to deploy broadband seismic equipment close to active volcanic activity

Three Years Post Fire Areas Natural Regeneration of Peat Swamp Forest in Merang, Musi Banyuasin District, South Sumatera

This study examines natural regeneration of tropical peat swamp forest after fire. The study area is located in Merang Peat Swamp Forest (PSF) in Musi Banyuasin District. Merang PSF is situated over a large peat dome that stores huge amount of carbon. 23 sample plots were established in the area burned in 2015. The regeneration of understorey, seedlings, and saplings was recorded in each plot. Meanwhile, peat depth and its maturity were identified to determine the soil characteristic of study area. After 3 years of fire, the area already covers densely by understorey mainly pakis udang (Stenochlaena palustris), pakis tanah (Nephrolepis exaltata), and resam (Gleichenia linearis) with depth of root zone reach about 40 cm in some plots. The native peat swamp species showed minimal regeneration during third years after fire due to understorey covering and limited number of surviving trees. The natural regeneration of woody species was dominated by bangun-bangun (Melicope glabra) and sepongol (Evodia sambuciana) which were calculated about 371 saplings/ha and 200 saplings/ha respectively. Those all two species also founded in the seedlings stage. The peat depth varied from 0.32 m to 4.71 m with peat maturity is dominantly hemic in the subsurface. This regeneration information provides useful indications for restoration options, which could be done by assisted natural regeneratio

Implementasi Sistem Kontrol Kadar Ozon Menggunakan Logika Fuzzy dan Monitoring Performa pada Sterilisator

Subsistem kadar ozon pada alat sterilisator belum memiliki fitur untuk kontrol kadar ozon. Karena ozon dengan konsentrasi lebih dari 1 ppm memiliki efek buruk pada kesehatan, oleh karena itu perlu dikendalikan kadar ppmnya agar tidak menimbulkan efek buruk pada kesehatan. Serta belum ada fitur monitoring performa pada sterilisator untuk memantau kinerja alat selama proses sterilisasi berlangsung. Pada subsistem kontrol kadar ozon menggunakan metode fuzzy untuk mengendalikan kadar ozon yang akan masuk ke box sterilisator dengan input error dan delta error kadar ozon serta aktuator berupa motor servo yang dikople dengan valve untuk mengatur derajat buka tutup valve agar dapat mengendalikan jumlah ozon yang akan masuk ke dalam box sterilisator. Hasil penelitian yang telah dilakukan adalah respon peralihan sistem pada konfigurasi close loop dengan FLC jauh lebih lambat dibandingkan dengan open loop. Yang mana pada pengujian open loop untuk mencapai kadar ozon sebesar 3 ppm dibutuhkan delay time (Td) sebesar 6,5 detik, rise time (Tr) sebesar 6,34 detik, peak time (Tp) sebesar 20 detik dan settling time (Ts) sebesar 10,45 detik sedangkan pada pengujian close loop membutuhkan delay time (Td) sebesar 8,05 detik, rise time (Tr) sebesar 10,1 detik, peak time (Tp) sebesar 40,21 detik dan settling time (Ts) sebesar 15,15 detik. Serta fitur monitoring pada sterilisator dapat digunakan untuk memantau kinerja alat, yang mana data ditampilkan berupa nilai angka dan grafik secara realtime dengan delay sekurang-kurangnya membutuhkan waktu 4,35 detik