Judul: Pengaruh Pemberian Abu Sekam, P, dan K terhadap Pertumbuhan dan Produksi Kedelai Hitam pada Budi Daya Jenuh Air di Lahan Pasang Surut
Abstrak: The experiment was carried out to evaluate the effect of husk ash, phosphorus, and potassium fertilizer on the growth and production of black soybean under saturated soil culture on tidal swamps. The experiment was conducted in the tidal swamps of South Sumatera Province, Banyu Urip village, sub District of Tanjung Lago, Banyuasin District, Palembang since April to August 2014. This experiment was using Randomize Complete Block Design with three replications. The concentration of husk ash as the first factor consist of 0, 1 000, 2 000, 3 000 kg ha-1, the concentration of phosphorus fertilizer as the second factor consist of 36 and 72 kg ha-1 P2O5, and the concentration of potassium fertilizer as the third factor consist of 30 and 60 kg ha-1 K2O. Saturated soil culture (SSC) technique was used to support the cultivation of soybeans in tidal swamps. The results showed that the effect of husk ash concentration, interactions of husk ash and phosphorus fertilization, interaction of husk ash and potassium fertilization and interaction of husk ash, phosphorus and potassium fertilization increased the ammount of trifoliat leaves. The optimum combination of 1.26 ton ha-1 husk ash, 36 kg ha-1 P2O5 phosphorus fertilization and 30 kg ha- 1K2O potassium fertilization gave the highest productivity by 4.21 ton ha-1and decreased the dose of Phosphorus and Potassium fertilizer
Keyword: Bogor Agricultural University (IPB), under saturated soil culture, potassium, phosphorus, husk ash, black soybean

Judul: The Effect of Doses of Phosphorus and Potassium Fertilizers on the Growth and Production of Soybean (Glycine max (L.) Merrill)
Abstrak: Kedelai merupakan salah satu komoditas prioritas yang diupayakan untuk ditingkatkan produksinya guna mengurangi impor. Upaya peningkatan produksi nasional kedelai di antaranya perbaikan teknik budi daya melalui pengaturan pupuk. Pupuk fosfor (P) dan kalium (K) menjadi salah satu pupuk dasar yang dibutuhkan untuk budi daya kedelai. Penelitian ini bertujuan mendapatkan informasi mengenai pengaruh dosis pupuk P dan K terhadap pertumbuhan dan produksi kedelai. Penelitian dilakukan di Kebun Percobaan IPB Sawah Baru dari bulan September hingga Desember 2021. Percobaan menggunakan rancangan kelompok lengkap teracak (RKLT) dengan dua faktor percobaan, yakni dosis pupuk P (0, 50, 100, dan 150 kg SP-36 ha-1) dan dosis pupuk K (0, 100, dan 150 kg KCl ha-1). Varietas yang digunakan adalah Anjasmoro. Hasil penelitian menunjukkan pemberian pupuk P mempercepat umur panen serta menaikkan indeks luas daun, nilai kehijauan daun fase R1, bobot kering tajuk, laju pertumbuhan tanaman fase R5−R8, bobot biji per tanaman, bobot ubinan, dan potensi hasil kedelai. Dosis 150 kg SP-36 ha-1 menghasilkan bobot biji per tanaman, bobot ubinan, dan potensi hasil tertinggi dibanding dosis lainnya. Hasil panen perlakuan pupuk P 100 kg SP-36 ha-1 dan 150 kg SP-36 ha-1 melampaui potensi hasil varietas. Pemupukan K memperpanjang fase pengisian polong (R5) dan meningkatkan tinggi tanamana pada 9 MST, bobot kering tajuk, bobot biji per tanaman, bobot 100 butir, bobot ubinan, dan potensi hasil kedelai. Dosis 150 kg KCl ha-1 menghasilkan komponen produksi kedelai tertinggi dibanding dosis lainnya., Soybean is one of the priority commodity which production is being increased in order to reduce imports. Efforts to increase national soybean production by improving cultivation techniques through fertilizer regulation. Phosphorus (P) and potassium (K) fertilizers are one of the basic fertilizers needed for soybean cultivation. This research aims to obtain information on the effect of doses of P and K fertilizers on soybean growth and production. The research was conducted at Sawah Baru Experimental Field and Post-harvest Laboratory of IPB University from September to December 2021. This research used a randomized complete block design (RCBD) with two experimental factors, the dose of P fertilizer (0, 50, 100, and 150 kg SP-36 ha-1) and the dose of K fertilizer (0, 100, and 150 kg KCl ha-1). Variety used was Anjasmoro. The results showed that the application of P fertilizer accelerated harvest age and increased leaf area index, leaf greenness in R1 phase, culm and leaf dry weight, rate of plant growth in R5−R8 phase, weight of seeds per plant, tile weight, and soybean yield potential. A dose of 150 kg SP-36 ha-1 produced the highest weight of seeds per plant, tile weight, and yield potential compared to other doses. The yields of fertilizer treatments of P 100 kg SP-36 ha-1 and 150 kg SP-36 ha-1 exceeded the yield potential of the variety. K fertilization extended age of pods filling (R5) and increased plant height at 9 WAP, culm and leaf dry weight, weight of seeds per plant, weight of 100 seeds, tile weight, and soybean yield potential. The dose of 150 kg KCl ha-1 resulted in the highest soybean production component compared to other doses.
Keyword: age of pods filling, culm and leaf dry weight, harvest age, seed weight, yield potential

Judul: Invers dari Matriks Circulant
Abstrak: Matriks circulant adalah matriks yang entrinya bergeser satu kolom ke kanan secara berurutan, sehingga untuk mengetahui entri dari matriks circulant dapat dilihat dari kolom pertama ataupun baris pertama. Salah satu sifat yang dimiliki matriks circulant, yaitu inversnya juga berupa circulant. Sehingga, untuk mencari invers matriks dari circulant dapat dilakukan dengan mencari entri di baris pertama atau di kolom pertama. Pada karya ilmiah ini ditentukan invers matriks circulant dengan menggunakan metode discrete Fourier transform dan sifat-sifat kenormalan pada matriks circulant.
Keyword: Matriks circulant, discrete Fourier transform, kenormalan matriks