Judul: Pengembangan Inventory Management System Produk Pertanian Koperasi Pesantren Al-Ittifaq
Abstrak: Koperasi Pesantren Al-Ittifaq merupakan koperasi yang terletak di Kecamatan Rancabali, Kabupaten Bandung, Provinsi Jawa Barat. Koperasi ini memiliki bisnis pertanian yang sudah berhasil memasok produk sayur-sayuran dan buah-buahan ke supermarket, rumah makan dan pasar tradisional. Walaupun bisnis yang berlangsung sudah cukup besar, proses transaksi masih dilakukan secara manual menggunakan spreadsheet dengan cara menginput satu per satu data pesanan pembeli. Oleh karena itu, diperlukan sebuah sistem yang mampu membantu koperasi memproses transaksi sehingga dapat menghemat waktu dan mengurangi resiko human error. Pengembangan sistem dilakukan menggunakan metode prototyping sebanyak dua iterasi. Sistem dibuat menggunakan MongoDB, ExpressJS, ReactJS dan NodeJS. Hasilnya, di iterasi pertama terdapat tujuh use case, salah satunya menginput data pesanan melalui file XML. Di iterasi kedua terdapat tambahan satu use case untuk merekap pesanan berdasarkan pembeli dan waktu. Untuk pengembangan lanjutan di masa depan, pihak Al-Ittifaq mengharapkan adanya fitur mendata pengeluaran koperasi.
Keyword: inventory management system, pertanian, koperasi, aplikasi web

Judul: User Interface Design for Horticultural Inventory Management Application at Al-Ittifaq Islamic Boarding School Cooperative Bandung
Abstrak: Pesantren Al-Ittifaq Bandung merupakan salah satu pesantren yang telah mewujudkan kemandiriannya dengan mengembangkan sektor perekonomian, agribisnis, dan teknologi. Hal ini dibuktikan dari perkembangan pesat Koperasi Pondok Pesantren Al-Ittifaq saat ini. Akan tetapi, sistem manajemen inventori alur masuk dan keluar barang di Koperasi Pondok Pesantren Al-Ittifaq masih dikelola secara manual menggunakan Excel dan Google Sheet. Oleh karena itu, dilakukan penelitian untuk perancangan user interface aplikasi inventory management hortikultura hingga tahap high-fidelity prototype dengan memperhatikan usability bagi penggunanya. Metode yang digunakan pada penelitian ini yaitu metode User Centered Design dengan framework RABBIT process sebanyak satu kali iterasi. Pengujian dilakukan kepada tiga pengguna yaitu sekretaris, bendahara, dan manager purchasing Koperasi Pondok Pesantren Al-Ittifaq. Hasil pengujian menghasilkan rata-rata skor System Usability Scale sebesar 71.67 dengan kategori acceptable berdasarkan acceptability ranges. Berdasarkan hasil pengujian tersebut, maka dapat disimpulkan bahwa user interface yang dikembangkan telah memenuhi usability bagi penggunanya., Al-Ittifaq Bandung Islamic Boarding School is one of the Islamic boarding schools that realizes its independence by developing the economic, agribusiness, and technology sectors. The rapid development of the Al-Ittifaq Islamic Boarding School cooperative proves this. However, the inventory management system for goods entering and exiting the cooperative is still managed manually using Excel and Google Sheets. Therefore, research was carried out to design the user interface of an application for horticultural inventory management up to the high-fidelity prototype stage by paying attention to usability for its users. The method used in this research is the User Centered Design method with the RABBIT process framework in one iteration. Testing is carried out on three users, namely the secretary, treasurer, and purchasing manager of the Al-Ittifaq Islamic Boarding School cooperative. The test results produced an average System Usability Scale score of 71.67 with an acceptable category based on the acceptability range. Based on the test results, it can concluded that the user interface developed has fulfilled its usefulness for its users.
Keyword: inventory management, user-centered design, user interface

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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