Judul: Pengaruh Mulsa Jerami terhadap Laju Perubahan Kadar Air Tanah dan Pertumbuhan Tanaman Padi (Oryza Sativa L.)
Abstrak: Increased level of soil moistured can be problem to the growth of the plant. The purpose of this research is to know the influence of straw mulch on the rate of change of moisture content of soil and plant growth rice. This fields research using random design group at 18 plots experiement, 9 comparterments without straw mulch and 9 compartements with mulch. Moisture content of soil in all area had been decrease once the land is no longer being given water, with an lowest average rate of declinewas indicated by the land that use a treatment of straw mulch, which amounted to -0.3%/days. The highest average height of plants and number of plantlets was indicated by the plant that use the treatment of mulch, which amounted to 43.2 cm 25 plantlets with Inpari 10 as the most responsive varieties.
Keyword: Rice, Drought, Straw mulch, Soil Moisture

Judul: Pengaruh Pemberian Mulsa Jerami Padi dan Kepadatan Tanah terhadap Pertumbuhan dan Produksi Padi Gogo (Oryza sativa L.)
Abstrak: Food security issues are strongly associated to the availability of food and land that affecting plant growth and production. Intensive tillage in conventional farming systems results poor soil condition (low fertility and soil physics characteristic, especially soil compaction) that fail to support plant growth. Soil compaction improvement is one of management effort on soil physics properties to obtain more suited physical environment for plant growth especially paddy. This research was aimed to study the effect of rice straw application and soil compaction on soil physics characteristic and to determine the soil bulk density and dose of mulch that effective for paddy growth and yield. Soil compaction treatment was divided into three soil bulk densities i.e. 0.8, 1.0, and 1.2 g/cm3. Each soil compaction was treated by rice straw mulch application in various doses i.e. 0%, 30%, 60%, and 90% of covered surface. Completed random design is used as experimental design and Honesty Significant Different (HSD) is used to identify the effect of treatment. The results showed that the interaction between soil compaction and mulch affect significantly on plant height in 5 weeks after growing, number of tillers in 4 weeks after growing, wet weight of root, wet biomass, weight of dry grain at harvest, time of harvest. Soil compaction was significantly affecting the field capacity water content, soil resistance before planting, plant height at 7 and 8 weeks after growing, number of tillers at 6, 8, and 9 weeks after growing also dry biomass also water content, bulk density and total of pore spaces after planting. Mulch application had only significant effect on plant height at 6 weeks after harvest. Soil bulk density suited for paddy growth and yields is 1.0 g/cm3 with 90% of mulch dose.
Keyword: upland rice, Situ Patenggang, straw rice mulch, soil compaction

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf