Judul: Effect of Shading Intensities on Fruit Position of Chilli Pepper (Capsicum frutescens L.)
Abstrak: Cabai rawit (Capsicum frutescens L.) merupakan tanaman hortikultura yang memiliki nilai ekonomi tinggi dan banyak dikonsumsi di masyarakat. Permasalahan utama pada produksi tanaman cabai khususnya pemanenan adalah biaya dan tenaga kerja. Salah satu upaya yang dapat dilakukan adalah penerapan prinsip pemanenan mekanis. Penelitian ini bertujuan mengetahui pengaruh pemberian beberapa intensitas naungan terhadap posisi buah cabai rawit untuk mendukung mekanisasi panen. Penelitian dilakukan di Kebun Percobaan Babakan Sawah Baru, IPB pada September 2021-Maret 2022. Rancangan percobaan menggunakan Split Plot Rancangan Kelompok Lengkap Teracak (RKLT) 2 faktor. Faktor pertama sebagai petak utama yaitu naungan yang terdiri dari 7 taraf, yaitu tanpa naungan, naungan 25%, 30%, 50%, 60%, 90%, dan 100%. Faktor kedua sebagai anak petak yaitu waktu pemberian naungan terdiri atas tiga stadia yaitu saat tanaman berbunga pertama kali, 2 minggu setelah berbunga (MSB), dan 4 MSB. Percobaan menggunakan 3 ulangan, sehingga terdapat 63 satuan percobaan. Setiap ulangan terdiri dari 20 tanaman, sehingga jumlah tanaman yang akan ditanam sebanyak 1260 tanaman dengan 5 tanaman contoh pada setiap ulangan. Hasil penelitian menunjukkan posisi buah cabai dipengaruhi oleh perlakuan intensitas naungan dan stadia pertumbuhan dilihat dari adanya perbedaan arsitektur tajuk tanaman cabai. Tinggi tanaman cabai semakin meningkat dan tajuk melebar dengan semakin tingginya tingkat naungan sampai 60%. Desain pemanenan mekanisasi perlu memperhatikan faktor agronomi khususnya naungan., Chili pepper (Capsicum frutescens L.) is a horticultural crop that has high economic value and is widely consumed as fresh by Indonesians. The main problems in the production of chili plants, especially harvesting, are costs and labor. Thus, the application of mechanical harvesting is important. However, the mechanical harvesting in chili peppers is still lacking. This study aimed to determine the effect of providing several shades of intensities on the fruit position of chili pepper to support harvest mechanization. The experiment was conducted in Babakan Sawah Baru Experimental Farm, IPB from September 2021 to Maret 2022. The experiment used a 2-factor Split Plot Complete Randomized Group Design (RKLT). The first factor was shade which consisted of 7 levels, namely no shade, 25% shade, 30%, 50%, 60%, 90%, and 100% as the main plot. The second factor as a subplot was the time of shading (the growth stage of chili plants), which consisted of three growth stages, namely when the plants flowered for the first time, 2 weeks after flowering (WAF), and 4 WAF. The experiment was carried out in 3 replications, so there were 63 experimental units. Each experimental unit consisted of 20 plants, with 5 sample plants per plot. The results showed that the position of the chili peppers was affected by the intensity of the shade and the growth stadia as seen from the differences in the canopy architecture. The height of the chili plants increased and the canopy widened with increasing shade levels up to 60%. In mechanized harvesting, agronomy factors need to be considered, especially shade intensity.
Keyword: environmental factors, growth, labor, plant architecture

Judul: The Effect of Shading Time for Growth and Yield of  Chili Pepper (Capsicum frutescens L.)
Abstrak: Cabai rawit (Capsicum frutescens L.) merupakan salah satu tanaman hortikultura di Indonesia yang memiliki nilai ekonomi tinggi dan tingkat kebutuhan yang tinggi. Permasalahan utama dalam produksi tanaman cabai rawit adalah harga penjualan cabai rawit yang berfluktuasi. Fluktuasi harga cabai rawit ini seringkali tidak menguntungkan petani karena pada saat produksi melimpah harga cabai rawit turun, tetapi pada produksi yang sedikit harga cabai rawit naik. Penelitian ini bertujuan mengetahui pengaruh waktu pemberian naungan terhadap pertumbuhan dan hasil tanaman cabai rawit pada lokasi yang berbeda. Penelitian dilakukan di Kebun Percobaan Leuwikopo, IPB pada Agustus 2022 hingga Maret 2023. Rancangan percobaan menggunakan Nested (tersarang) Rancangan Kelompok Lengkap Teracak (RKLT) 2 faktor. Faktor pertama yaitu lokasi yang terdiri dari lahan A (samping Green House) dan lahan B (lahan antara kelas). Faktor kedua yaitu naungan yang terdiri dari 3 taraf, yaitu tanpa naungan, naungan 50%, dan naungan 90%. Percobaan menggunakan 3 ulangan, sehingga terdapat 18 satuan percobaan. Setiap ulangan terdiri dari 54 tanaman, sehingga jumlah tanaman yang ditanam sebanyak 972 tanaman dengan 10 tanaman contoh pada setiap ulangan. Hasil penelitian menunjukkan perlakuan intensitas naungan mempengaruhi penundaan panen tanaman cabai rawit. Pemberian naungan mampu menunda panen cabai rawit di lahan lebih lambat hingga 12 hari. Intensitas naungan 50% dan lokasi N2 memberikan hasil yang terbaik pada parameter yang diuji. Hasil panen dan kandungan capcaisin tanaman cabai rawit tertinggi didapatkan pada tanaman kontrol atau tidak ternaungi. Jarak tanam perlu diperhatikan agar lebar kanopi antar tanaman tidak tumpang tindih., Chili pepper (Capsicum frutescens L.) is one of the horticultural crops in Indonesia that has high economic value and high demand. The main problems in the production of chili pepper is fluctuating selling price. These fluctuations often unprofitable for farmers because when production is abundant will be falling price, but when production is low there will be rises price of chili pepper at different locations. This study aimed to determine the effect of shading time for the growth and yield of chili pepper. The experiment was conducted in Leuwikopo Experimental Farm, IPB from August 2022 to Maret 2023. The experimental design used a 2-factor Nested Complete Randomized Group Design (RKLT). The first factor was location which consisted of land A (next to Green House) and land B (between classes). The second factor was shading which consisted of 3 levels, namely no shade, 50% shade, and 90%. The experiment was carried out in 3 replications, so there were 18 experimental units. Each replicates consisted of 54 plants, so the number of plants was 972 plants with 10 sample plants in each replicates. The results showed that shading intensity was affected the harvest delay of chili pepper. Shade treatment was able to delay the harvest of chili pepper in the field up to 12 days slower. Shading intensity of 50% and location of N2 gave the best results for the parameters tested. The highest yields and capsaicin content of chili pepper were obtained from unshaded plants. Spacing needs to be considered so the width of the canopy between plants does not overlap.
Keyword: growing environtment, price, harvest age, growth, productivity

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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