Judul: Harvest and Postharvest Handling of Apples (Malus domestica Borkh.) in PT. Kusuma Agrowisata, Batu, East Java
Abstrak: Kegiatan magang dilaksanakan di PT Kusuma Agrowisata, Batu, Jawa Timur selama tiga bulan dari Januari sampai April 2020. Kegiatan magang bertujuan mempelajari kegiatan budidaya tanaman apel dan aspek khusus panen dan pasca panen buah apel dan faktor yang mempengaruhinya. Kegiatan yang dilakukan yaitu mengikuti seluruh kegiatan budidaya dari aspek teknis, aspek manajerial, dan pengamatan aspek khusus panen dan pasca panen apel. Pengamatan aspek khusus bertujuan untuk mengetahui perbedaan tahun penanaman apel Anna di tiga blok yaitu Blok C2 tahun 1999, Blok C3 tahun 1997, dan Blok A3 tahun 2002 terhadap karakteristik buah yang dipanen dan susut bobot apel selama penyimpanan di suhu ruang. Hasil dari pengamatan menunjukkan lokasi berpengaruh nyata terhadap bobot buah, dan tidak berpengaruh nyata terhadap diameter melintang dan diameter membujur buah. Lama penyimpanan buah apel Anna berkorelasi positif terhadap persentase susut bobot buah apel Anna. Lama penyimpanan mempengaruhi 98,78% persentase susut bobot buah yang diamati. Penyimpanan 10 hari merupakan waktu simpan dengan susut bobot tertinggi disusul oleh penyimpanan 5 hari dan 0 hari. Apel Anna dengan waktu simpan 10 hari menunjukkan perubahan mutu fisik diantaranya buah mulai membusuk dan muncul serangan cendawan pada kulit buah., The internship was carried out at PT Kusuma Agrowisata, Batu, East Java for three months from January to April 2020. The internship was aimed to studying apple plant cultivation activities and specific aspects of the apple harvest and post-harvest also the factors that influence it. The activities comprised participating in technical aspects from all cultivation activities, managerial aspects, and observing specific aspects of the apple harvest and post-harvest. Observation of specific aspects aims to determine the differences in the planting year of Anna apples in three blocks, namely Block C2 in 1999, Block C3 in 1997, and Block A3 in 2002 on the characteristics of the harvested fruit and the weight loss of apples during storage at room temperature. The results of the observation indicated that location had a significant effect on fruit weight, and had no significant effect on fruit transverse diameter. The length storage time correlated positively to the percentage of Anna’s apples weight loss. Storage time affects 98.78% percentage of fruit weight loss that have been observed. Storage of 10 days is the storage time with the highest weight loss, followed by storage of 5 days and 0 days. Observation of the fruit that was stored for 10 days showed changes in physical quality, including the fruit began to rot and fungal attack appeared.
Keyword: fruit characteristic, harvest, storage, weight loss

Judul: Management of Defoliating and Pruning for Flowering Induction of Apple Manalagi (Malus sylvestris Mill.) in PT. Kusuma Agrowisata.
Abstrak: Kegiatan magang dilaksanakan di PT. Kusuma Agrowisata, Batu, Jawa Timur selama tiga bulan mulai dari Januari hingga April 2020. Tujuan umum kegiatan magang agar mahasiswa dapat mempelajari dan mendapatkan pengalaman dalam bekerja secara nyata mengenai aspek teknis dan manajerial budidaya tanaman apel, khususnya mengenai pengelolaan perompesan daun dan pemangkasan untuk induksi pembungaan pada tanaman apel. Metode yang digunakan pada kegiatan magang dengan mengumpulkan data primer dan data sekunder. Data primer diperoleh dengan mengikuti seluruh kegiatan teknis, pengamatan di lapangan, dan wawancara. Data sekunder diperoleh melalui arsip kebun, laporan manajemen, dan studi pustaka. Pengamatan yang dilakukan berupa pengamatan aspek teknis, aspek manajerial, dan aspek khusus. Pengamatan aspek teknis dengan melakukan kegiatan sebagai karyawan harian lepas (KHL) dengan mengikuti seluruh rangkaian kegiatan budidaya tanaman apel. Aspek manajerial sebagai pendamping pengawas kebun apel dengan mengawasi kinerja KHL, membuat jurnal, dan membuat rencana kegiatan. Pengamatan aspek khusus mengenai perbedaan interval waktu perompesan daun ke pemangkasan yang dilakukan pada 2 blok apel Manalagi (Malus sylvestris Mill.) yaitu blok B3 (3 hari) dan blok A3 (6 hari). Teknik perompesan daun dilakukan secara manual menggunakan tangan dan pemangkasan dilakukan secara mekanis menggunakan gunting pangkas serta gergaji. Perbedaan interval waktu perompesan daun dan pemangkasan antara blok B3 dengan A3 tidak berpengaruh nyata terhadap jumlah tunas vegetatif dan generatif, persentase pecah tunas, jumlah kuncup bunga yang muncul, jumlah bunga yang mekar, serta jumlah bunga yang gugur. Perbedaan interval waktu memengaruhi kecepatan waktu pecah tunas, waktu muncul kuncup bunga, dan waktu bunga mekar antara kedua blok. Blok B3 lebih cepat mengalami fase perkembangan bunga dibandingkan dengan blok A3 karena tanaman apel blok B3 lebih dulu dilakukan pemangkasan., Internship activities were carried out in PT. Kusuma Agrowisata, Batu, East Java for three months from January to April 2020. The general purpose of internship activities was to assist and develop technical and managerial work experience for the student in growing apples, especially in the management of defoliating and pruning for flowering induction. The method used in internship activities by collecting primary and secondary data. The primary data are collected by all technical activities, field observations, and interviews. The secondary data are collected from company archives, management reports, and literature studies. The aspects of observation are including technical aspects, managerial aspects, and specific aspects. The technical aspect observation activities were carried out as labor to do apple cultivation activities. The managerial aspects were carried out as a companion of the supervisor to supervise labor, writing a working journal, and planning activities. The specific aspect observations were about the different effect of time intervals of defoliating to pruning, were made on two blocks of apples var. Manalagi (Malus sylvestris Mill.); block B3 (3 days) and block A3 (6 days). The defoliating using the manual technique by hand and pruning using mechanical technique with shears and saws. The different time intervals between block B3 and A3 had no significant effect on the total of vegetative and generative buds, the percentage of bud burst, the total of flower buds, the total of blooming flowers, and the total of flowers drop. The different time intervals effect, the bud bursting
Keyword: bud brust, generative bud, petal falls, secondary branch

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.
Keyword: