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Prediksi Penyebaran Covid-19 di Indonesia dan Jawa Timur dengan Metode Extended Kalman Filter
Get PDFSaat ini pandemi Covid-19 telah menyebar ke seluruh dunia, tidak terkecuali Indonesia. Dalam pemodelan matematika, penyebaran Covid-19 dapat digambarkan melalui model matematika epidemiologi SIRD (Susceptible, Infected, Recover, Death). Pertama model non-linier SIRD didiskritkan dan selanjutnya dilakukan prediksi puncak penyebaran Covid-19 dengan menggunakan metode Extended Kalman Filter (EKF). Dengan data aktual Infected, Recover, dan Death yang merupakan data harian, modifikasi EKF dapat memprediksi puncak infeksi Covid-19 untuk satu bulan kedepan. Simulasi dilakukan dengan 3 macam pembatasan pergerakkan pada masyarakat yaitu : tanpa adanya pembatasan (100%), 75%, dan 50% pergerakkan. Hasil prediksi dengan modifikasi EKF menunjukkan dengan dilakukan pembatasan pergerakkan 50% pada masyarakat di Indonesia dan Jawa Timur dapat mempercepat terjadinya puncak infeksi dengan jumlah individu terinfeksi lebih sediki
Himpunan Fuzzy dan Rough Sets
Get PDFThe concept of a fuzzy set was introduced by Zadeh in 1965. Fuzzy set is a mathematical model of vague qualitative or quantitative data, frequently generated by means of the natural language. The model is based on the generalization of the classical concepts of set and its characteristic function. Intuitionistic fuzzy sets are sets whose elements have degrees of membership and non-membership. Intuitionistic fuzzy sets have been introduced by Atanassov in 1983 as an extension fuzzy sets. On the other hand, the concept of rough set was proposed by Pawlak 1982. Since then the subject has been investigated in many papers. The overall aim of this paper is to present an introduction to some of main concepts related to fuzzy sets, intuitionistic fuzzy sets and rough sets. We investigate Crisp sets and characteristic functions, fuzzy sets, intuitionistic fuzzy sets, rough sets and probabilistic rough sets
Implementasi Vehicle Routing Problem with Multiple Trips pada Masalah Pengangkutan Sampah
Get PDFSalah satu tantangan yang dihadapi oleh setiap daerah, termasuk di Kota Bogor adalah masalah pengelolaan sampah. Dari tahun ke tahun, jumlah penduduk di Kota Bogor semakin bertambah. Hal ini menyebabkan volume sampah di Kota Bogor semakin meningkat. Volume sampah di Kota Bogor setiap harinya mencapai 2900 meter kubik. Akan tetapi, sampah yang terangkut ke Tempat Pembuangan Akhir (TPA) Galuga hanya 2100 meter kubik. Hal ini dapat menyebabkan penumpukan sampah di Tempat Pembuangan Sementara (TPS). Setiap hari, Dinas Lingkungan Hidup (DLH) Kota Bogor telah melakukan pengangkutan sampah. Akan tetapi, DLH Kota Bogor memiliki keterbatasan, seperti banyaknya armada pengangkutan sampah, biaya operasional, dan sebagainya. Pada penelitian ini, model Vehicle Routing Problem with Multiple Trips diterapkan pada masalah pengangkutan sampah dengan tujuan meminimumkan biaya operasional pengangkutan sampah. Solusi diperoleh dengan bantuan perangkat lunak LINGO 11.0 menggunakan metode Branch and Bound. Hasil yang diperoleh sebesar Rp.9.469.072,22, dengan rincian Bogor Tengah sebesar Rp.941.650,205, Bogor Utara sebesar Rp.1.980.716,265, Bogor Timur sebesar Rp.1.032.562,5, Bogor Barat sebesar Rp.1.448.955,075, Bogor Selatan sebesar Rp.2.456.550, dan Tanah Sareal sebesar Rp.1.617.638,175
Perencanaan Sistem Pemeliharaan menggunakan Metode Reliability Centered Maintenance Gas Engine Compressor PT. Perda Daya Gas
Get PDFPT. Perta Daya Gas adalah Perusahaan joint venture yang dibentuk dan didirikan oleh PT. Pertamina Gas(Pertagas) dan PT. Indonesia Power (IP). PT. Perta Daya Gas mendirikan fasilitas Compressed Natural Gas (CNG) PlantTambak Lorok yang bertujuan sebagai “Peak Shaving” untuk memenuhi kebutuhan beban puncak kelistrikan pada subsistem Jawa Tengah & Daerah Istimewa Yogyakarta yang berasal dari Pembangkit Listrik Tenaga Gas & Uap (PLTGU)Tambak Lorok yang dioperasikan oleh PT. Indonesia Power. CNG Plant Tambak Lorok merupakan fasilitas kompresidan penyimpanan gas alam dalam bentuk CNG yang dikerjakan oleh 10 unit Gas Engine Compressor (GEC) identikuntuk mengubah 20 – 24 bar menjadi 250 bar. Mengingat pentingnya kinerja GEC, diperlukan langkah perawatandengan metode yang tepat. RCM merupakan suatu strategi maintenance yang memberikan metode terstruktur dansistematis untuk menganalisis fungsi dan kegagalan dari suatu aset fisik yang berfokus dalam mempertahankan fungsiaset tersebut. Proses penyusunannya terbagi menjadi 2 analisis yaitu kuantitatif dan kualitatif. Analisis kuantitatifdilakukan dengan pendistribusian kegagalan dengan software Reliasoft Weibull++6 untuk mengetahui parameterperhitungan nilai keandalan yang dapat digunakan dalam acuan interval perawatan tiap mesin. Analisis kualitatifmenggunakan metode Failure Mode and Effect Analysis yang kemudian dikembangkan dalam bentuk RCM DecisionWorksheet. Dari analisis yang dilakukan, interval perawatan untuk menjaga nilai keandalan tidak turun di bawah 0.6adalah 80 jam untuk GEC K-101, 260 jam untuk GEC K-102, 220 jam untuk GEC K-103, 240 jam untuk GEC K-104, 42jam untuk GEC K-105, 150 jam untuk GEC K-106, 160 jam untuk GEC K-107, 240 jam untuk GEC K-108, 140 jam untukGEC K-109 dan 130 jam untuk GEC K-110. Analisis kualitatif mengidentifikasi ada 69 failure mode pada Gas EngineCompressor. 67 failure mode bisa dicegah dengan scheduled discard task dan 2 failure mode bisa dicegah denganscheduled restoration task
Implementation of Fuzzy AHP Method to Determine the Best Alternative of Electric Energy Source for RKEF PT Vale Indonesia
Get PDFPT. Vale Indonesia is planning to build a RKEF to produce an additional 10 kT of nickel in a year. The 70 MW RKEF power requirement will be met from excess power from 3 hydro power plant and an additional 20 MW from other power plants. The selection of additional power plants is complicated because the selection process involves multiple conflicting criteria that can be either qualitative or quantitative, therefore a MCDM approach is carried out to obtain the best alternative by ranking according to criteria with regards to their relative importance and calculating weight of each criterion. Furthermore, the selection of the best alternative power plants will use the analogy between AHP and the geometric mean Fuzzy AHP method to choose a power plant. This selection is managed using six criteria, namely the price of electricity or LCOE, funding sources for investment costs, the effect of greenhouse gases, availability of resources, effects to the operations to the processing plant and utilities, and the duration of the project. There are 4 alternatives compared, namely PLTD, PLTS, ORC and PLTA, and the results of the selection show that PLTA has the highest value and was chosen as the best alternative
Modeling and Control of Anti-Rolling Gyro System to Stabilize Single-Track Vehicle
Get PDFTwo-wheeled vehicle has many advantages such as small size, more efficiency, and more maneuverable. These advantages come at the lack of stability and safety. To improve the stability and safety of a two-wheeled vehicle, the Control Moment Gyroscopic Stabilization is considered. This system is composed to generate counteracting roll stabilizing torque. In this study, the system of gyroscopic stabilizer is simulated and validated to be implemented into a two-wheeled vehicle. Proportional-Integral-Derivative (PID) controller is designed to control the gimbal for generating the balancing torque. The performance of the proposed controller is evaluated through simulation for non-linear cases. The result of the non-linear model confirms a good balance in terms of rapid response
Spin-Orbit Effect on Thermal Properties of Half-Heusler Alloy FeVSb
Get PDFFeVSb, a family of Half-Heusler alloy, is categorized as an n-type semiconductor which has a high figure of merit that makes this material to be one of the promising candidates for a thermoelectric device. In FeVSb, Fe and V atoms which have d-orbitals can be considered to have spin-orbit interaction that can affect the electronic structure and thermal properties of this material. In order to investigate how strong the spin-orbit interaction affect this material, we do the first-principles study by implementing the spin-orbit interaction to investigate the change of the band structure and thermal properties of FeVSb. Our results show that the spin-orbit interaction affects the band structure of the material indicated by the energy splitting in the electronic structure which increase the Seebeck coefficient, electrical conductivity, and thermal conductivity but slightly reduce the figure of merit values of FeVSb
Investigating the Motions Behavior of a Ferry in Waves Caused by Damaged Conditions
Get PDFA progressive flooding-ingress of water to a compartment of a damaged ship affects the motions of a ship. In this present study, the behavior of the motion of a ferry caused by damaged conditions in waves was investigated through the experimental work. The leakage of compartments was made into several scenarios including one, two, and three damaged compartments, and the damaged ship model was simulated in heading and beam waves. The research results show the one damaged compartment on the engine room (ER) affected extreme stern trim as well as Void No.1 affected extreme bow trim. The two damaged compartments on the water ballast tank (WBT) No.2 and Steering gear room (SGR) resulted in extreme stern trim as well as WBT No.1 and Void No.1 affected extreme bow trim. The heave, pitch, and roll responses on the damaged Void No.1 are higher comparing with the damaged ER. Also, the heave, pitch, and roll responses on damaged SGR and WTB No.2 are higher than Void No.1 and WBT No.1. The peak resonances of heave RAO on bow trim affect higher magnitude than on stern trim. Pitch or roll RAO caused by the increased bow trim or stern trim in head and beam waves has a small magnitude within the response