Judul: Mobile Application for Monitoring Feed and Weight  Gain of Cattle Using Flutter
Abstrak: Sapi merupakan penyedia utama kebutuhan daging merah di Indonesia, dengan kontribusi signifikan terhadap kebutuhan gizi masyarakat. Berdasarkan data sektor pertanian, kehutanan, dan perikanan, kontribusi sapi potong mencapai 18 juta ekor dan sapi perah 582,2 ribu ekor pada tahun 2021, mengalami peningkatan dari tahun sebelumnya. Pemeliharaan ternak sapi di Indonesia sebagian besar dilakukan oleh peternak skala kecil dengan metode pencatatan yang belum terintegrasi secara digital. Oleh karena itu, diperlukan sistem pencatatan yang lebih praktis dan efisien. Penelitian ini bertujuan mengembangkan sebuah aplikasi mobile berbasis Flutter untuk memantau pakan dan kenaikan berat badan sapi. Aplikasi ini dirancang untuk mencatat data pakan dan berat badan sapi secara digital agar peternak dapat memantau secara lebih akurat. Penelitian ini menggunakan metode agile dengan framework Scrum yang melibatkan tahapan perencanaan product backlog, sprint planning, daily scrum, sprint review, dan sprint retrospective. Sistem pencatatan digital ini diharapkan dapat meningkatkan efisiensi dan efektivitas dalam pengelolaan ternak sapi., Cattle are the primary source of red meat in Indonesia, making a significant contribution to the nutritional needs of the population. According to data from the agriculture, forestry, and fisheries sectors, the contribution of beef cattle reached 18 million heads, and dairy cattle 582.2 thousand heads in 2021, showing an increase from the previous year. Livestock farming in Indonesia is mostly carried out by small-scale farmers with record-keeping methods that are not yet digitally integrated. Therefore, a more practical and efficient record-keeping system is needed. This study aims to develop a mobile application based on Flutter to monitor cattle feed and weight gain. This application is designed to digitally record cattle feed and weight data so that farmers can monitor it more accurately. This study uses the agile method with the Scrum framework, involving stages of product backlog planning, sprint planning, daily scrum, sprint review, and sprint retrospective. This digital record-keeping system is expected to improve efficiency and effectiveness in cattle management.
Keyword: aplikasi mobile, flutter, pencatatan ternak, pemantauan pakan

Judul: Rancang Bangun Aplikasi Pendataan Ternak Sapi Potong Menggunakan RFID Berbasis Android
Abstrak: Usaha peternakan sapi potong terbagi atas dua sektor, yaitu usaha ternak sapi potong rakyat dan perusahaan. Sebagian besar peternakan sapi potong di Indonesia merupakan peternakan rakyat. Pola pemeliharaannya masih tradisional, serta kepemilikan jumlah ternak yang terbilang masih sedikit antara 2-3 ekor/peternak. Karena kurangnya pengawasan dan kontrol terhadap ternak, standar mutu hasil ternak menjadi salah satu permasalahan yang mempersempit lingkup pasar dari usaha ternak sapi potong rakyat. Penelitian ini bertujuan untuk merancang dan membangun aplikasi berbasis Android yang dapat dipergunakan untuk membantu para peternak tradisional untuk mencatat dan mengakses data ternak sapi potong. Pendekatan dalam tahap perancangan aplikasi menggunakan metode pengembangan System Development Life Cycle (SDLC) yang terdiri dari investigasi sistem, analisis sistem, desain sistem aplikasi, implementasi sistem aplikasi, dan pemeliharaan sistem aplikasi. Hasil dari penelitian ini adalah aplikasi yang dapat mencatat dan menyajikan data ternak sapi potong sesuai dengan EPC pada label RFID yang dimiliki., The beef cattle farming business is divided into two sectors, namely the small-scale farmers and companies. The majority of beef cattle farming in Indonesia is carried out by small-scale farmers, with traditional breeding methods and a small number of cattle per farmer, usually between 2-3 heads of cattle. Due to the lack of supervision and control over the cattle, the quality standards of the cattle become one of the problems that narrow the market scope of small-scale beef cattle farming. This research aims to design and build an Android-based application that can be used to help traditional farmers record and access data on beef cattle. The approach in the application design phase uses the System Development Life Cycle (SDLC) method, which consists of system investigation, system analysis, application system design, implementation of the application system, and maintenance of the application system. The result of this research is an application that can record and present data on beef cattle according to the Electronic Product Code (EPC) on the RFID tag that the cattle have.
Keyword: Android, EPC, RFID, Sapi Potong

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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