Judul: Analisis Infiltrasi Tanah pada Berbagai Penggunaan Lahan di Kebun Percobaan Cikabayan, Dramaga
Abstrak: Infiltration rate of soil is influenced by a variety soil properties, such as soil texture, type of clay mineral, soil structure, aggregate stability, soil water content, soil organic matter content, soil pore distribution, and land use. The purpose of this study was to determine the infiltration rate of the soil on several land uses, and soil infiltration relationships with other soil properties, especially soil aggregate stability, organic matter content, and the content and type of cation. The result showed that the initial soil infiltration rate (t = 0,05 hour) was highest on Durian Garden 90 cm/hr, followed by Open Land 80 cm/hr, Cassava Garden 79 cm/hr, and the lowest in Rubber Garden 60 cm/hr. The initial soil infiltration rate is more determined by initial soil water content. Rubber Garden have the lowest soil infiltration rate because it has the highest initial soil water content. Cassava Garden has a constant infiltration rate of 7,80 cm/hr that classified as slightly fast. Infiltration rate constant on Rubber Garden 6,00 cm/hr, followed by Durian Garden 5,40 cm/hr, and Open Land have the lowest infiltration rate constant of 5,20 cm/hr which all classified as medium. Based on observations made soil infiltration rate is not always influenced by land use and some soil properties such as high aggregate stability, organic matter content, and exchangeable cation. Initial soil moisture condition controls initial soil infiltration rate. Tuber formation can loosen the soil so as to stimulate the movement of water into the ground to be faster.
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Judul: Karakteristik Fisik Tanah, Infiltrasi, dan Aliran Permukaan DAS Cisadane Hulu
Abstrak: Soil infiltration rate is influenced by soil bulk density, texture, and soil porosity. Degradation of soil physic characteristics will decrease soil infiltration rate, therefore will be increases surface runoff. The aim of the research was to identify soil physic characteristics, soil infiltration rate, and surface runoff in Upper Cisadane Watershed. Soil infiltration rate was measured using double ring infiltrometer on pine forest, shrubs and bush, mixed garden, and settlement areas. The result shows that a highest soil bulk density (lowest of soil porosity) were found on settlement areas where as the lowest soil bulk density (highest of soil porosity) were on mixed garden. Mixed garden has a highest of soil infiltration rate i.e 285 mm/h (very fast), where as the lowest soil infiltration rate was found on pine forest of 110 mm/h (medium to fast). Stream discharge of Upper Cisadane River was fluctuated with maximum and minimum discharges were 8.63 m3/s and 0.13 m3/s respectively. The value of coefficient of stream regime was 66.31 and runoff coefficient was 0.22. Based on those value, hydrology function of Upper Cisadane Watershed was classified in medium to good qualities.
Keyword: soil physics characteristics, soil infiltration, runoff, land use

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular