Judul: Pemberian Larutan Hara untuk Budidaya Tanaman Akar Wangi (Vetiveria zizanioides (L.) Nash) Menggunakan Teknologi Hidroponik Sistem Terapung (THST)
Abstrak: Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi larutan hara terhadap pertumbuhan dan hasil akar wangi (Vetiveria zizanioides (L.) Nash) varietas Verina 2 dengan menggunakan Teknologi Hidroponik Sistem Terapung (THST). Penelitian ini merupakan penelitian lanjutan dari penelitian sebelumnya Penelitian disusun berdasarkan rancangan kelompok lengkap teracak (RKLT) yang terdiri atas dua percobaan: (1) tanaman yang belum dilakukan pemotongan akar (3 ulangan), (2) tanaman yang sudah dilakukan pemotongan akar (6 ulangan), dengan satu faktor dan tiga taraf: konsentrasi larutan hara 200 ppm, konsentrasi larutan hara 400 ppm, dan konsentrasi larutan hara 800 ppm. Hasil penelitian menunjukkan bahwa konsentrasi larutan hara berpengaruh nyata pada tinggi tanaman, jumlah anakan, jumlah anakan baru, dan bobot kering tajuk pada tanaman yang belum dilakukan pemotongan akar, serta berpengaruh nyata terhadap bobot basah akar pada tanaman yang sudah dilakukan pemotongan akar. Perlakuan konsentrasi larutan hara 200 ppm menghasilkan pertumbuhan tanaman yang tidak berkembang dengan baik. Tanaman akar wangi yang ditanam dengan pemberian konsentrasi larutan hara antara 400 ppm sampai 800 ppm memperoleh pertumbuhan tajuk dan perkembangan akar tanaman yang lebih baik, oleh karena itu THST dapat diterapkan untuk budidaya akar wangi pada konsentrasi larutan hara tersebut sehingga dapat menghasilkan pertumbuhan tajuk dan perakaran yang baik.
Keyword: floating system, hydroponic, nutrient solution, vetiver

Judul: Pemberian Larutan Hara untuk Budidaya Tanaman Akar Wangi (Vetiveria zizanioides (L.) Nash) Menggunakan Teknologi Hidroponik Sistem Terapung (THST)
Abstrak: The objective of this experiment was to determine the effect of concentration of nutrient solution on growth and yield of vetiver (Vetiveria zizanioides (L.) Nash) Verina 2 variety using Hydroponic Floating System Technology (HFST). This experiment that is a continuation of previous experiment. The experiment is based on a randomized complete block desing which consists of two experiments: (1) a plant that has not been done cutting the roots (3 replicates), (2) plants that have been done cutting the roots (6 replicates), with one factor and three-level: nutrient solution concentration of 200 ppm, nutrient solution concentration of 400 ppm and nutrient solution concentration of 800 ppm. The results showed that the concentration of the nutrient solution had significant effect on plant height, number of tillers, number of new saplings, canopy dry weight in plants that have not done cutting the roots, and root fresh weight in plants that have been done cutting the roots. Treatment of nutrient solution concentration of 200 ppm resulted that the growth of plants do not develop properly. Vetiver plants that grown with the provision of nutrient solution concentration between 400 ppm to 800 ppm acquire a better canopy growth and root development of plants, therefore THST can be applied to the cultivation of vetiver on the concentration of the nutrient solution so it could produce a better canopy growth and root development.
Keyword: Bogor Agricultural University (IPB), vetiver, nutrient solution, hydroponic, floating system

Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
Keyword: