Judul: The Diversity of Physical and Chemical Quality of Calina Papaya Fruit
Abstrak: Pepaya merupakan tanaman yang dapat berproduksi sepanjang tahun di Indonesia. Pepaya memiliki banyak varietas sehingga memiliki rasa, bentuk dan ukuran yang beragam. Keragaman pepaya unggul perlu dievaluasi sebagai upaya mempertahankan karakter kualitasnya. Tujuan penelitian ini mengkarakterisasi dan mengklasifikasi keragaman kualitas fisik dan kimia buah pepaya Calina. Metode pengambilan sampel menggunakan Metode Purposive Random Sampling dengan sampel sebanyak 50 pohon. Setiap pohon sampel diambil empat buah sehingga terdapat total 200 buah pepaya. Setiap pohon sampel diberi kode bentuk buah berdasarkan Descriptor for Papaya. Penelitian dilaksanakan di Kebun Pepaya Desa Babakan Lebak, Kelurahan Balumbang Jaya, Kecamatan Bogor Barat, Kota Bogor dan Laboratorium Pasca Panen Fakultas Pertanian IPB dari bulan April hingga bulan Juli 2022. Hasil percobaan menunjukkan terdapat keragaman bentuk dan rongga buah Pepaya Calina yaitu elongate, lengthened cylindrical, oval, dan globular dengan bentuk rongga round, irregular dan star. Pepaya Calina memiliki bentuk buah di ujung tangkai tipe depressed dan digolongkan sebagai buah pepaya berukuran kecil hingga sedang. Rongga buah pepaya berbentuk star memiliki bobot jumlah biji yang lebih tinggi. Buah berbentuk elongate dan lengthened-cylindrical memiliki bentuk sesuai dengan deskripsi pepaya Calina. Buah berbentuk globular memiliki nilai PTT paling tinggi (11,90 ⁰Brix) sedangkan buah berbentuk oval memiliki nilai PTT paling rendah (10,64 ⁰Brix). Kandungan vitamin C berkisar antara 123,89-127,14 mg/100g tidak berbeda nyata antar bentuk buah. Bobot buah berkorelasi positif dengan panjang, diameter, tebal daging buah, volume buah, dan bobot biji., Papaya is a plant that can grow all year round in Indonesia. Papaya has many varieties, so it has a variety of flavors, shapes, and sizes. The diversity of superior papaya in the field should be evaluated to maintain its quality character. The research purpose is to characterize and classify the diversity of physical and chemical qualities of Calina papaya. The sampling method used the Purposive Random Sampling Method with a sample of 50 trees, each tree sampled four papayas, so there were 200 total papayas. The sample tree is coded with a fruit shape based on the Descriptor for Papaya. The research was conducted from April to July 2022 at Papaya Gardens in Babakan Lebak Village, Balumbang Jaya Village, West Bogor District, Bogor City, and the Post-Harvest Laboratory of the Faculty of Agriculture, IPB. The results of the experiment showed that there were variations in the shape and cavity of the Papaya Calina, namely elongate, lengthened-cylindrical, oval, and globular with round, irregular and star cavity. Calina papaya has a fruit shape at the end of the stem of the depressed type and is classified as a small to medium-sized papaya fruit. The star-shaped papaya fruit cavity has a higher seed weight. The elongated and lengthened-cylindrical fruit has a shape according to the description of the Calina papaya Globular fruit has the highest PTT value (11.90 oBrix) while oval fruit has the lowest PTT value (10.64 oBrix). Vitamin C content ranged from 123.89-127.14 mg/100g not significantly different between fruit shapes. Fruit weight was positively correlated with length, diameter, flesh thickness, fruit volume, and seed weight.
Keyword: tropical fruit, characterization, classification, fruit quality

Judul: Analisis Peningkatan Kualitas pada Rantai Pasok Buah Pepaya Calina
Abstrak: Post-harvest handling of local fruits especially in Calina papaya supply chain (IPB 9) has problems that can affect the value of the quality appearance so it needs quality improvement. The purposes of this research are (1) Identifying the key attributes of Calina papaya quality improvement based on desires of consumer and to know the level of customer satisfaction using Quality Function Deployment, (2) Analyzing the cause of quality problems Calina papaya, and (3) Analyzing strategies or ways on improving the quality of Calina papaya in Indonesia. The result in this research that there are three main attributes of customer satisfaction are the sweet taste, color of fruit meat, and texture of fruit meat. Supply chain activities that have the highest interests of rate based on analysis of QFD are the maintenance (value 521) of cultivation. There are two attributes that had mismatches of quality, which are bruise and pests-diseases. The causes are materials, management, labor, environment, machine and method. The highest priority that can be chosen as the alternative strategy is increasing production capacity, product quality, and food safety assurance by expanding the distribution network with score 6,290
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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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