Judul: Analisis kapasitas infiltrasi dan hantaran hidrolik berbagai jenis tanah dengan vegetasi penutup teh dan karet pada PTPN VLII Perkebunan Panglejar, Kabupaten Bandung
Abstrak: Infiltration capacity and hydraulic conductivity are two i~nportailt parameters characteristing soil physics. Both par'metirs can help in pla~lnings oil and water management techniques. In this research, the determination of infiltration capacity and hydraulic conductivity was carried out in the field. Soil types in the researcl~ area were Andosol and Latosol under rubber and tea plantation at PTPN VIII Panglejar Pla~ltation,B andung. Result of infiltration ~neasurements howed that the infiltration capacity in loa~ny texture (Andosol) were higher than that in the clay texture (Latosol). Similar result were found under tea plantation, where infiltration capacity was higher than rubber plantation. The infiltration capacity was higher under vegetation with more coverage, lower crop height, and more litter. The coarsertexture the higher the infiltration. On the contrary, the heavier texture the lower the infiltration capacity. The result of saturated hydraulic conductivity measulement sl~owed that' the average value of saturated hydraulic conductivity in the Andosol (2.94 crnfhour) higher than Latosol (1.76 cmlhour). It was caused by soil texture different, especially fraction of fine clay and coarse sand. The vegetation factor that has influence on the value of saturated hydraulic conductivity, measured in the depth of 100 cm was roothing system. Rubber crops had deeper roothing system (seed bed size was 60x60~60c m) than tea crops root (seed bed size was 20x20~20 cm) showed higher the value of saturated hydraulic conductivity. Average value of hydraulic conductivity in the rubber plantation was 2.85 cmlhour whereas in tea plantation was 2.12 cmlhour. It is, showed that dense roots in the soil profile wili create more porous condition, so, that water easier flowing trough or therefore value of I~ydraulicc o~lductivityw as higher.
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Judul: Infiltration Rate of Soil with Different Land Uses at IPB University, Bogor Regency, West Java
Abstrak: Informasi laju dan kapasitas infiltrasi suatu tanah dengan berbagai jenis penggunaanya penting untuk diketahui sebagai informasi dasar bagi pengelolaan sumberdaya air. Penelitian ini bertujuan untuk mendapatkan informasi laju dan kapasitas infiltrasi tanah pada kebun sawit, kebun karet dan semak di Kampus IPB Dramaga dan menganalisis model pendugaan infiltrasi terbaik. Laju dan kapasitas infiltrasi diketahui melalui pengukuran penggunaan ring infiltrasi ganda dan menggunakan model infiltrasi Horton dan Kostiakov. Pemilihan model terbaik antara Model Horton dengan Kostiakov menggunakan kriteria uji-t, root mean square error (RMSE) dan mean absolute error (MAE). Hasil pengukuran infiltrasi menunjukkan lahan semak memiliki kapasitas infiltrasi tertinggi (21.62 cm/jam), sedangkan kapasitas infiltrasi di tanah kebun karet dan kebut sawit masing-masing sebesar 5.15 cm/jam dan 3.25 cm/jam. Model Horton dan Model Kostiakov baik digunakan dalam pendugaan laju infiltrasi. Model Kostiakov memberikan hasil dugaan laju infiltrasi tanah dengan penggunaan lahan sebagai kebun sawit, kebun karet dan semak di Kampus IPB Dramaga yang lebih baik daripada Model Horton., Information on soil infiltration rate capacity with different land uses is essential to knowing basic water resource management information. This study aims to obtain information on soil infiltration rate and capacity with land uses such as oil palm and rubber plantations and shrubs in IPB University, Dramaga Campus, and to analyze the best infiltration estimation, model. Infiltration rate and capacity were measured by using double rings infiltrometer and the Horton and Kostiakov infiltration models. The performance of the infiltration models was based on the result of the t-test, residual mean square error (RMSE), and mean absolute error (MAE). The infiltration measurements show the soil infiltration rate in shrub land use was higher than in rubber plantation and oil palm plantation land uses, with the infiltration capacity of 21.62 cm/hr, 5.15 cm/hr, and 3.25 cm/hr, respectively. Horton dan Kostiakov models are both good for estimating infiltration rate; however, the Kostiakov model estimate infiltration rate better than Horton Model.
Keyword: Infiltration, Oil palm plantations, Rubber plantations, Shrubs

Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
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