4 research outputs found

    ANALISIS SUBSPACE CLUSTERING MENGGUNAKAN DBSCAN DAN SUBCLU UNTUK PROYEKSI PEKERJAAN ALUMNI PERGURUAN TINGGI

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    Subspace clustering diproyeksikan sebagai teknik pencarian untuk mengelompokkan data atau atribut pada klaster yang berbeda, Pengelompokan dilakukan dengan menentukan tingkat kerapatan data dan juga mengidentifikasi outlier atau data yang tidak relevan, sehingga masing-masing cluster ada dalam subset tersendiri. Tesis ini mengusulkan inovasi algoritma subspace clustering based on density connection. Pada tahap awal akan dihitung kerapatan dimensi, hasil kerapatan dimensi akan dijadikan data masukan untuk menentukan klaster awal yang berdasarkan kerapatan dimensi, yakni dengan menggunakan Algoritma DBSCAN. Data pada setiap klaster kemudian akan diuji apakah memiliki hubungan dengan data pada klaster yang lain, yakni dengan menggunakan Algoritma SUBCLU. Hasil dari penelitian ini ditemukan bahawa SUBCLU tidak memiliki un-cluster dataset nyata, sehingga persepsi hasil cluster akan menghasilkan informasi yang lebih akurat sedangkan untuk kepuasan kerja dataset DBSCAN membutuhkan waktu lebih lama daripada metode SUBCLU. Untuk lebih besar dan lebih kompleks data, kinerja SUBCLU terlihat lebih efisien daripada DBSCAN

    Analysis Of Large Scale Climate Data: How Well Climate Change Models And Data From Real Sensor Networks Agree?

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    Research on global warming and climate changes has attracted a huge attention of the scientific community and of the media in general, mainly due to the social and economic impacts they pose over the entire planet. Climate change simulation models have been developed and improved to provide reliable data, which are employed to forecast effects of increasing emissions of greenhouse gases on a future global climate. The data generated by each model simulation amount to Terabytes of data, and demand fast and scalable methods to process them. In this context, we propose a new process of analysis aimed at discriminating between the temporal behavior of the data generated by climate models and the real climate observations gathered from groundbased meteorological station networks. Our approach combines fractal data analysis and the monitoring of real and model-generated data streams to detect deviations on the intrinsic correlation among the time series defined by different climate variables. Our measurements were made using series from a regional climate model and the corresponding real data from a network of sensors from meteorological stations existing in the analyzed region. The results show that our approach can correctly discriminate the data either as real or as simulated, even when statistical tests fail. 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