Multiscale Spatial Polygonal Object Granularity Factor Matching Method Based on BPNN

Spatial object matching is one of the fundamental technologies used for updating and merging spatial data. This study focused mainly on the matching optimization of multiscale spatial polygonal objects. We proposed a granularity factor evaluation index that was developed to promote the recognition ability of complex matches in multiscale spatial polygonal object matching. Moreover, we designed the granularity factor matching model based on a backpropagation neural network (BPNN) and designed a multistage matching workflow. Our approach was validated experimentally using two topographical datasets at two different scales: 1:2000 and 1:10,000. Our results indicate that the granularity factor is effective both in improving the matching score of complex matching and reducing the occurrence of missing matching, and our matching model is suitable for multiscale spatial polygonal object matching, with a high precision and recall reach of 97.2% and 90.6%.

Kajian Kelestarian Sumberdaya Lahan Berbasis Analisa Kemampuan Lahan di DAS Serang

Kondisi pertumbuhan jumlah penduduk yang tinggi tidak hanya berpengaruh terhadap kebutuhan air atau pangan, melainkan dapat menyebabkan meningkatnya konversi lahan sebagai pemenuh kebutuhan hidup manusia. Adanya konversi kawasan lindung menjadi kawasan pertanian atau pemukiman mampu meningkatkan potensi kerusakan lingkungan. Tingkat kerusakan lingkungan memang tidak dapat dihindari atau tidak dapat di kontrol secara bersamaan, namun mampu dikurangi melalui perencanaan penggunaan lahan, pembangunan, serta manajemen yang baik. DAS Serang sebagai satu dari empat DAS kritis di Daerah Istimewa Yogyakarta yang menjadi bagian dari 108 DAS kritis di Indonesia perlu dilakukan kajian terkait sumberdaya lahan sebagai pendukung terciptanya perencanaan penggunaanlahan yang berkelanjutan. Penelitian ini dilakukan dengantujuan menganalisis kelas kemampuan lahan untuk mengetahui tingkat ketimpangan penggunaan lahan pada wilayah DAS Serang. Penenentuan kemampuan lahan menggunakan satuan bentuklahan sebagai unit analisis dengan membandingkan metode weight factor matching dan subjective factor matching. Metode tersebut merupakan bagian dari teknik pembandingan (matching) yang dilakukan dengan cara mencocokan dan membandingkan karakteristik lahan dan kriteria kelas kemampuan lahan. Hasil yang didapatkanmeliputi 14 bentuklahan dan 11 unit lahan yang analisis dengan kelas kemampuan I hingga VIII yang disajikan dalam peta dan gambaran spasial ketimpangan penggunaan lahan pada DAS Serang.

A modified tucker’s congruence coefficient for factor matching

Since factor analysis is one of the most often used techniques in psychometrics, comparing or combining solutions from different factor analyses is often needed. Several measures to compare factors exist, one of the best known is Tucker’s congruence coefficient, which is enjoying newly found popularity thanks to the recent work of Lorenzo-Seva and ten Berge (2006), who established cut-off values for factor congruence. While this coefficient is in most cases very good in comparing factors in general, it also has some disadvantages, which can cause trouble when one needs to compare or combine many analyses. In this paper, we propose a modified Tucker’s congruence coefficient to address these issues.

IDENTIFIKASI KESESUAIAN LAHAN UNTUK JATI (Tectona grandis Linn.f) DI PT. MELAPI TIMBER, KALIMANTAN TIMUR Identify Suitable Land for Jati (Tectona grandis L.f) in PT. Melapi Timber, East Kalimantan

Land evaluation of a tract of land, for its suitability to be planted with a particular plantation species is an importantstep for species choice in plantation forest. A weight factor matching (WFM) approach of this study, was used to identifysuitable land for jati (Tectona grandis L.f) in PT. Melapi Timber, East Kalimantan. Land suitability is affected by climate,soil and topograph. According to WFM, the results indicated that important variables which limit T. grandis in theresearch area were pH, cation exchange capacity (CEC), potassium (P) and soil depth condition. The study results showthat 4 of 5 land units are marginally suitable (S3) for T. grandis cultivation in PT. Melapi Timber.Key words: Land evaluation, suitability, Tectona grandis L.f., weight factor matching (WFM)