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Performance Analysis of Cone Basin-Based Gravitational Water Vortex Power Plant (GWVPP) by Variations in the Number of Blades
Get PDFThe electricity supply is not evenly distributed for all regions in Indonesia. This is due to the lack of transportation access to reach these areas because of difficult terrain conditions. One of abundant energy sources available in nature is water, which can be used for micro-level power generation. Micro hydro generator usually uses a waterfall with a high head. However, not all of the water flow has a head tall. Therefore, this study proposes a promising prototype of a cone basin-based Gravitational Water Vortex Power Plant (GWVPP). The purpose of this study is to determine the performance of the cone basin-based GWVPP prototype by variation in the number of blades. The vortex turbine is designed with a water flow rate of 169.63 liters/minute and a cone basin with square-shaped blades and variations in the number of blades, namely 2, 4, and 6, with the same turbine blade area of 0.01 m2 . It was found that an increase in the number of blades enhances mechanical characteristics of, e.g. torque and rotational speed, as well as electrical characteristics, e.g. voltage, current, and electric power. The maximum result is achieved when the number of blades is six with the rated power of 5 mW and the rotation speed of 119.351 rpm
DETERMINATION OF SECONDARY METABOLITE CONTENT, TOTAL PHENOLIC ANTIOXIDANT TEST, AND TOXICITY OF ULIN LEAF EXTRACT (Eusideroxylon zwageri Teijsm. & Binn)
No full textUlin leaf (Eusideroxylon zwageri Teijsm. & Binn) is one of the traditional Indonesian medicinal plants. In this research, the secondary metabolite content, antioxidant activity, cytotoxic and total phenolic content were tested. The extraction process by maceration starts from hexane, ethyl acetate and methanol. The content of secondary metabolites of ironwood leaves are flavonoids, phenolics, steroids, terpenoids, and alkaloids. The results of the antioxidant activity test using the DPPH method (1,1-Diphenyl-2-Picrylhydrazil), methanol extract showed very strong activity IC50 10.96 mg/L, moderate ethyl acetate extract 115,409 mg/L and weak hexane extract IC50 368,555 mg/L. L. This result correlated with the total phenolic yield, methanol extract had the highest value of 162.95 mg GAE/Gram, followed by ethyl acetate extract of 96.7 mg GAE/Gram and hexane with a value of 19.85 mg GAE/Gram. The results of the cytotoxic test using the (BSLT) method on hexane extract had very strong toxicity LC50 82.1675 mg/L, methanol extract and weak ethyl acetate LC50, respectively; 683,282; and 812.456 mg/L.Key word : Ulin, Antioxidants, Total Phenolic, cytotoxi
Paving Block from Residue of PS/LDPE/PP Plastic Pyrolysis Mixed with Palm Oil Bottom Ash (POBA)
Get PDFThe residue of plastic mixture pyrolysis can be used for making paving blocks. Fibers in plastics can be used as an adhesive against other materials and can increase the strength of paving blocks. Palm oil bottom ash (POBA) was added to replace the role of cement, which has the same content as cement, i.e., silica (Si). This study aimed to see the effect of palm oil bottom ash and sand added to the residue of plastic mixture pyrolysis (i.e., PS/LDPE/PP) on the quality of paving blocks. The paving block as a test object was made by combining two materials. The residue of plastic mixture pyrolysis and LDPE plastic melt was mixed with a mass ratio of 70:30%, referred to as material I. Furthermore, palm oil bottom ash and sand were mixed with mass ratios of 100, 80, 60, 40, and 20%, referred to as material II. The ratio of ingredients I and II used was 1: 1. Testing of the quality of paving blocks includes a compressive strength test and a water absorption test. The test results showed that the ratio of PS/LDPE/PP mixture (50:25:25) had a compressive strength of 104.1 kg/cm2 or 102.08 MPa and the water absorption of 2.4% at the ratio of palm oil bottom ash and sand at 80:20%. Adding palm oil bottom ash can reduce the paving block’s compressive strength, and the residue’s LDPE content can affect water absorption because of its chemical structure properties. Therefore, less LDPE residue is needed to obtain optimal water absorption values in paving blocks and add palm oil bottom ash. Based on this compressive strength in this study and SNI 03-0691-1996, these paving blocks can be used for garden
Eksplorasi Teknik Pengelolaan Limbah Masker Bekas Menjadi Material Produk Interior
Get PDFVirus Covid-19 saat ini mewabah ke seluruh dunia yang menjadi fenomena pandemic di abad 21 ini. Virus ini mudah menular lewat interaksi antar manusia dan menyerang sistem pernafasan. Untuk mencegah penularan tersebut pemakaian masker medis sangat disarankan bagi setiap orang untuk menyaring partikel virus sehingga tidak terhirup ke dalam sistem pernafasan. Penggunaan masker medis secara massal ini menyebabkan terjadinya penumpukan limbah masker bekas yang sangat banyak dan belum bisa dikelola dengan baik. Penelitian ini bertujuan untuk menemukan teknik mengolah limbah masker dengan bantuan teknik mix media, daur ulang, dan teknik pemanasan. Metode penelitian yang digunakan adalah kualitatif dan eksperimen. Hasil Penelitian ini menemukan teknik terbaik untuk mengolah limbah masker. Teknik terbaik yang dihasilkan adalah teknik heating dalam mengolah limbah masker secara maksimal
Assessing Highrise Building Construction in Semarang Using Green Construction Site Index (GCSI)
Get PDFAs the demand for housing increases, building construction ignore the adverse implication exposed to the environment. The objective of the study was to analyze the performance of the ongoing construction projects implementing the green construction concept. The tool applied was the Green Construction Site Index (GCSI) to assess five construction projects categorizing into three groups or specifications (uncommercialized, non-residential building; commercial, residential building; and commercial, non-residential building). The index of efficiency, productivity, and awareness upon three types of buildings was 4.06, 4.49, and 4.31 respectively. Meanwhile, the overall index obtained by the construction project type I, II, and III was 4.07, 4.33, and 4.35 respectively. The tool might be considered an opportunity to contractors; although, further investigation on its application in other types of buildings is needed
Analisis Pengaruh Penggunaan Hydraulic Engineering Software Terhadap Kinerja Waktu Proyek Perencanaan Sistem Pengelolaan Air Limbah Domestik Terpusat (SPALD-T) Skala Kota
Get PDFKeterlambatan menjadi fenomena yang universal di hampir semua proyek konstruksi di dunia. Hal ini terjadi pada semua tahapan proyek terutama pada tahap konstruksi tetapi tidak sedikit juga terjadi keterlambatan pada tahap perencanaan dan desain [1]. Pada proyek infrastruktur seperti SPALD-T juga seringkali terjadi keterlambatan pada tahap perencanaan. Terdapat cukup banyak faktor penyebab keterlambatan pada fase perencanaan yang salah satunya yaitu masih kurangnya penggunaan Advanced Engineering Software dalam melakukan desain perencanaan proyek [2]. Dalam proyek pemerintah seperti proyek perencanaan SPALD-T tidak sedikit yang masih menggunakan software konvensional seperti Microsoft Excel dalam desain jaringan pipa air limbah sehingga engineer akan membutuhkan waktu yang banyak untuk melakukan proses desain ataupun koreksi. Penelitian ini bertujuan untuk menganalisa pengaruh penggunaan hydraulic engineering software terhadap kinerja waktu pada proyek perencanaan SPALD-T Skala Kota. Dengan menggunakan metode analisis linear berganda dihasilkan bahwa dengan penggunaan hydraulic engineering software terdapat pengaruh positif terhadap kinerja waktu perencanaan proyek SPALD-T sebesar 52,5% karena hydraulic engineering software memiliki faktor-faktor seperti kemudahan analisis, visualisasi jelas, cakupan desain, pengelolaan skenario, desain otomatis, integrasi dengan GIS konversi dan akurasi. Dimana faktor yang paling berpengaruh adalah pengelolaan skenario
Pemanfaatan Kolam Tampung Sebagai Upaya Mitigasi Banjir Kawasan Pada Sub Sistem Medokan Ayu Kota Surabaya
Get PDFMedokan Ayu is an area from Surabaya Drainage Master Plan 2018-2038, located in Rayon Jambangan and reported to be inundated. This caused by overcapacity of the existing drainage channel to accommodate the 2-year flood discharge. From 134 channels observed, 27 channels overflowed, and 20 out of 27 canals are located in residential areas so the inundation hampered the local citizens activities. For a discharge period of 10 years, overflow occurs in the upstream and the middle of the main channel due to the slope of the channel is too flat. Since it is not possible to change the base elevation upstream or downstream, a reservoir was created as a solution by utilizing the government's inventory area located near the downstream of the channel. This reservoir will have pump that stream the water back to downstream channel. So, with this flood control system, Medokan Ayu area can be free from inundation
Pemodelan Risiko Penyebaran COVID-19 di Surabaya Raya Menggunakan Model Cauchy Cluster Process
Get PDFCOVID-19 merupakan penyakit yang menyerang alat pernapasan. Jumlah kasus COVID-19 di Jawa Timur terus mengalami peningkatan tiap harinya khususnya wilayah Surabaya Raya meliputi Kota Surabaya, Kabupaten Gresik, dan Kabupaten Sidoarjo yang memiliki jumlah pasien terkonfirmasi positif tertinggi dibandingkan kabupaten/kota lainnya di Jawa Timur. Kota Surabaya menjadi penyumbangkan terbesar kasus terkonfirmasi postif COVID-19 di Surabaya Raya yaitu sebesar 60,1 %. Penelitian ini bertujuan untuk memodelkan risiko penyebaran COVID-19 di Surabaya Raya dengan melibatkan beberapa kovariat dimana kriteria pembandingnya yaitu nilai BIC terkecil dan envelope K-function. Hasil uji homogenitas menunjukkan penyebaran data kasus terkonfirmasi positif COVID-19 di Surabaya Raya tidak homogen dan untuk korelasi spasial dengan Inhomogeneous K-function diperoleh bahwa data cenderung membentuk kelompok atau klaster. Hasil pemodelan didapatkan bahwa model Inhomogeneous Cauchy Cluster Process setelah eliminasi merupakan model terbaik, dimana kovariat kepadatan penduduk dan kepadatan lokasi kerumunan yaitu pusat perindustrian dan tempat ibadah berpengaruh secara signifikan terhadap risiko penyebaran kasus terkonfirmasi positif COVID-19 di Surabaya Raya. Sementara itu, kepadatan pusat perbelanjaan tidak berpengaruh signifikan. Hasil prediksi risiko kasus terkonfirmasi positif COVID-19 di Surabaya Raya menunjukkan risiko penyebaran kasus terkonfirmasi positif COVID-19 di wilayah Kota Surabaya lebih tinggi jika dibandingkan dengan wilayah Kabupaten Sidoarjo maupun Gresik