Cocopeat machines that have been developed today, were carried out with variations in the speed of rotation, blade length, blade shape, and treatment of objects (coconut coir immersion). There has been no development of a cocopeat machine that focuses on variations of blade density. It is suspected that the blade density affects to the difference of cocopeat mass produced. This study was a true experiment. The dependent variable was cocopeat mass. The independent variables were blade density, consisting of σ1 (84/210π), σ2 (42/210π) and σ3 (21/210π). For each variation of the independent variable was conducted 10 experiments. The study sample was 30 pieces of coconut coir. The mass of each coconut coir was 50 grams. The engine's spin speed, length and blade shape, are the same for all samples. The data was analyzed using the t test at a significance level of 5%. The average mass values of cocopeat were σ1 (  = 16.5430; S1 = 1.9674), σ2 (  = 12.2650; S2 = 1.8341) and σ3 (μ3 = 10.0988; SD = 1.8943). The t test showed that the difference in the average value of cocopeat mass between groups were to12 = 5,030; to23 = 2,598; and to13 = 7,462. If t-table value for ν = 18 was 2,101, so . Ho was rejected and H1 accepted, so there was a difference of cocopeate mass that produced by poltesa cocopeat machine, which is effected by variations of blade density.

<p><em>The purpose of this study was to describe the process and results of making cocopeat dryers with a hybrid system based on solar panels. This research was conducted with a tool development method consisting of five steps, namely literature study, design, tool and material preparation, manufacturing, and functional tests. The study results were (1) the process of making cocopeat dryers with a hybrid system based on the solar panel was the calculation of solar panel components, frame making, coating of frames with the casing, assembling of electronic components, and functional tests. (2) The cocopeat dryer with a hybrid system based on solar panels that have been made has dimensions of 120 cm in length, 60 cm in width, and 130 cm in height—equipped with a 100 Wp solar panel, a 12 V 65Ah dry battery, a 600 W inverter, three 15W halogen lamps, and a 22W fan. (3) The functional test results show that the average temperature inside the dryer is 52.84oC, 8.56oC higher than the temperature outside the tool. The average humidity inside the dryer is 23.4%, 17.2% lower than the humidity outside the appliance.     </em></p>

Osilator kuantum anharmonik tidak dapat diselesaikan secara analitik, sehingga diperlukan metode lain untuk menentukan energi keadaan dasarnya. Pada penelitian ini, energi keadaan dasar osilator anharmonik kuantum diperoleh menggunakan metode random walk. Metode ini didasarkan pada probabilitas pergerakan acak partikel. Suku anharmonik yang digunakan adalah λx 3 dengan memvariasikan nilai λ. Teori gangguan dan metode kuantum difusi Monte Carlo digunakan untuk memverifikasi hasil metode random walk. Energi keadaan dasar osilator anharmonik kuantum yang diperoleh menggunakan metode random walk memilki sesilih maksimum sebesar 0,8% dibandingkan dengan teori gangguan dan 2,5 % dibandingkan dengan metode kuantum difusi Monte Carlo.

Masalah utama sistem hidroponik tenaga surya adalah belum ditemukannya metoda untuk mengoptimalkan waktu operasi pompa air. Diduga bahwa, jumlah panel surya dan aki, berpengaruh terhadap waktu operasi pompa air. Tujuan penelitian adalah mendeskripsikan pengaruh variasi rangkaian jumlah panel surya dan aki terhadap waktu operasi pompa air. Penelitian eksperimen ini memiliki variable terikat berupa waktu operasi pompa air serta variable bebas berupa variasi jumlah panel dan aki. Langkah penelitian adalah (1) merangkai panel surya (P) dan aki (A) dengan variasi 1P1A, 2P1A, 3P1A, 4P1A, 1P2A, 2P2A, 3P2A, dan 4P2A. (2) Menjemur setiap jenis rangkaian selama satu jam. (3) Memindahkan rangkaian pada tempat teduh dan menghidupkan pompa air. (4) Mencatat data waktu operasi pompa air. (6) Melakukan analisis data menggunakan uji-t dengan taraf signifikansi 5%. Hasil penelitian menunjukkan bahwa (1) semakin banyak penel surya maka waktu operasi pompa air semakin lama. (2) Semakin banyak aki maka waktu operasi pompa air semakin lama