Judul: Perhitungan Limpasan Permukaan dan Evapotranspirasi berdasarkan Neraca Air pada Pertanaman Kentang (Solanum Tuberosum L.)
Abstrak: Ketersediaan air merupakan salah satu faktor yang mempengaruhi pertumbuhan, perkembangan serta produksi tanaman kentang. Tanaman kentang cukup banyak dibudidayakan di Indonesia. Tanaman kentang biasa dibudidayakan pada ketinggian lebih dari 1000 m dpl dengan tingkat kemiringan yang cukup tinggi. Kondisi ini mempengaruhi ketersediaan air untuk pertumbuhan tanaman kentang. Tujuan penelitian ini adalah menghitung kehilangan air melalui evapotranspirasi dan limpasan permukaan pada tanaman kentang dengan menggunakan neraca air. Penelitian dilakukan mulai bulan Desember 2009 sampai Maret 2010 di Kebun Percobaan Balitbiogen Pacet-Cipanas, Cianjur. Perhitungan kehilangan air pada tanaman kentang dilakukan dengan pendekatan neraca air dengan persamaan ETat+Rot = θt-1-θt+Pt, dimana θt = kadar air tanah hari ke t, θt-1 = kadar air hari ke t-1, dan ETat+Rot = kehilangan air karena evapotranspirasi aktual dan runoff hari ke t. Evapotranspirasi actual diasumsikan sebesar 4 mm/hari. Hasil penelitian ini menunjukkan bahwa kondisi dimana curah hujan tinggi, terjadi runoff yang besar karena kapasitas infiltrasi dan perkolasi yang terbatas, dan tetap terjadi evapotranspirasi. Hal ini dapat mengurangi kadar air tanah selama masa pertumbuhan tanaman kentang. Kadar air tanah yang lebih tinggi menghasilkan laju pertumbuhan tanaman kentang yang lebih tinggi walaupun jarak tanamnya lebih rapat. Di samping kadar air tanah, ukuran bibit sangat menentukan hasil panen kentang.
Keyword: Potato, Water balance, Evapotranpiration, Runoff, Soil water

Judul: Pendugaan kehilangan air melalui perhitungan neraca air serta analisis pertumbuhan tanaman kentang (Solanum tuberosum L.)
Abstrak: The growth and the production of a plant are determined by favourable environment. Soil is water reservoir and planting area for which the capability to keep the water in the soil will determine the total water that can be used for the plant. Water availability in the soil is used by the plant to fullfil plant’s water requirement such actual evapotranspiration and runoff which can be calculated by using the water balance. The objective of this research is to calculate the potato water loss during the measurement through the water balance and to analyse the effect on potato growth. The result of this research shows that the potato water loss (actual evapotranspiration and runoff) during measurement on 37 days until 73 days after planting is 148-191 mm or 4.6 mm/days, whereas the run off is 28-59 mm or 19-30 % from total water loss potato. The relations between soil water content and the growth rate in each treatment has a different disposed. When the storage of soil water content is high, the growth rate is uncertainly high, and vice versa. The growth rate is of the potato in this research not only influenced by soil water content, but also influenced by other factors that are not observed in this research.
Keyword: 

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.
Keyword: