Aplikasi Filter Digital untuk Citra Mengandung Derau Salt and Pepper Menggunakan Metode Directional Weighted Minimum Deviation

Teknologi telekomunikasi berkembang begitu pesat, dari yang semula berkomunikasi menggunakan surat, berkembang komunikasi suara menggunakan telepon hingga kini telah sampai pada tahap komunikasi gambar dan video. Dalam proses pentransmisian data baik suara maupun gambar tidak terlepas dari adanya derau. Salah satu solusi dalam menjawab permasalahan tersebut adalah dengan mengembangkan teknologi Filter Digital. Dalam penelitian ini direalisasikan sebuah Filter digital dengan objek gambar menggunakan metode DWMD (Directionan Weighted Minumum Deviation) Filter dengan mendeteksi jenis derau salt and pepper. Metode DWMD Filter adalah metode pengolahan data digital berbasis arah dan standar deviasi yang memperbaiki Median Filter. Dengan membandingkan parameter PSNR maka diketahui bahwa DWMD dapat menghasilkan gambar lebih baik dari Median Filter. Metode Filter DWMD ini ditambah dengan penentuan Threshold otomatis untuk membantu proses filter menjadi lebih cepat dimana diambil selisih PSNR terbesar. Hasil eksperimen menunjukkan bahwa pada level derau 5% - 65% metode DWMD menghasilkan PSNR bernilai 21-36 dB dibandingkan dengan Median Filter sebesar 13-29 dB. Penelitian ini memiliki output berupa aplikasi desktop yang dilengkapi dengan fitur-fitur yang dapat menambahkan derau salt and pepper pada berbagai densitas dan mengakses citra yang dapat diubah ke dalam format grayscale.

Development Assessment of the Coal Industry of China Based on the Minimum Deviation Comprehensive Weight Evaluation Model

Coal is the most reliable energy resource in China and has been in existence for a long time. The development model of coal industry is of great significance to carbon emission and environmental protection. In order to evaluate the development mode of China’s coal industry, this paper presents the constructed evaluation index system of the development mode of the coal industry from two dimensions, demand pull and factor drive. And, coal consumption is the measurement index of demand pull and selecting resources, capital, technology, human resources, and the energy system form the measurement index of factor drive. By analyzing the evaluation index system of the coal industry development mode and optimal evaluation method, the minimum deviation comprehensive weighting evaluation model, based on the analytic hierarchy process (AHP), and entropy are constructed. The evaluation results show that the coal industry has continued the factor driven growth, driven by demand, in the past decades. Finally, the study analyzes the changes and challenges of the development of China’s coal industry from four aspects, development power, development mode, development effect, and development bottleneck, to provide support for revealing the internal mechanism of the development mode of China’s coal industry.

Prognóstico da série histórica do faturamento da indústria alimentícia brasileira utilizando técnicas de previsão

This paper’s objective is to verify which is the best forecasting technique, including the use of the forecasts’ combination to evaluate the prognosis of the Brazilian food industry’s revenues. The historical series of revenues has deterministic trend and seasonality. Thereby, the models chosen to work on were: SARIMA (3,0,0)×(0,1,1)12, SARIMA (4,0,0)×(2,0,0)12 and Holt-Winters Multiplicative. Analyzing the accuracy measures, to perform the series’ forecast it was used the combination of the three models, presented by the methods: Simple Arithmetic Mean, Ordinary Least Squares and Regression of Absolute Minimum Deviation. The results obtained by the forecast were satisfactory, showing that the Brazilian food industry’s revenues will have peaks of growth and decay in the next two years. Therefore, a preparation of the sector is necessary for the period in which a possible decrease in this revenue will occur, as well as dismissal of the workers, since it is the sector that most employs in Brazil.