Judul: Perencanaan Penggunaan Lahan Berkelanjutan untuk Tanaman Bawang Putih (Allium sativum L) di Kabupaten Tegal Provinsi Jawa Tengah
Abstrak: Garlic is one of the most popular agricultural commodities by the community in daily life. The benefits of garlic other than as the main seasoning in food can also be used as raw materials for herbal medicines. The average consumption of Garlic per capita from 2013 to 2017 is 0.231 ounces, 0.300 ounces, 0.355 ounces and 0.359 ounces, and 0.313 ounces. The national garlic development program by the Ministry of Agriculture in 2017 is conducting an acceleration program for self-sufficiency in garlic with the goal of fulfilling consumption needs, reducing imports, and self-sufficiency independently. Tegal Regency is one of the regions in Indonesia that has the potential to develop Garlic. This research has the aim of planning sustainable land use for garlic plants. To achieve the main objectives, objectives such as (1) delineating land use/cover in Tegal Regency, (2) analyzing the potential of land for garlic, (3) analyzing the sustainability of garlic farming, (4) formulating strategies to increase garlic production. Delineation of land cover/land use using SPOT 6 image interpretation in 2018. Analysis of land availability is carried out using forest area status maps, land cover/land use maps, and spatial plan maps that are overlaid to obtain land information available. Land suitability evaluation is done by matching the plant growth requirements with the characteristics and quality of garlic plant land. Sustainability analysis is carried out using Multidimensional Scaling (MDS) through the MDS questionnaire, and analysis of production improvement strategies using AHP-SWOT with Expert choice. The results of satellite imagery interpretation show that the largest area of land cover is in a paddy field and built-up land with an area of 54 143 hectares and 14 533 hectares, respectively. The actual land suitability analysis shows that the land in Tegal Regency is in the appropriate marginal class (S3) covering an area of 65 103 hectares, and not suitable (N) covering an area of 29 914 hectares. After an effort was made to improve the limiting factor in each land suitability into potential land suitability, the land suitability class increased to S2 and S3. The potential land area in class S2 is 69 329 hectares and the land area in class S3 is 24 414 hectares. Availability of land for the development of garlic covering an area of 3 419 hectares. The available land area suitable for garlic development is on an area of 3 419 hectares, with a fairly suitable land suitability class (S2) and according to marginal (S3). The most extensive land for S2 class is in Bojong District with an area of 744.9 hectares and the largest land for class S3 is in Kedungbanteng District with an area of 512.5 hectares. The results of the multidimensional analysis of the sustainability of garlic farming in Tegal district show that its sustainability status is in the fairly sustainable category with an index of 62.66. The sensitive attributes obtained from the sustainability analysis are the use of waste, use of pesticides, agricultural extension, land management, productivity, marketing reach. Product storage technology, technology suitability and assistance, marketing agencies, import policies. The intervention was carried out
Keyword: Analitical hierarchy process, kesesuaian lahan, Multidimentional scalling

Judul: Development of Backend Module on Garlic Land Suitability Spatial Decision Support System
Abstrak: Bawang putih merupakan salah satu komoditas hortikultura yang memiliki beragam manfaat dan banyak dikonsumsi. Permasalahan dalam meningkatkan produksi bawang putih bermutu adalah sulitnya menentukan lahan yang sesuai, karena bawang putih tidak dapat tumbuh di sembarang tempat. Lahan yang tidak sesuai mengakibatkan pertumbuhan tanaman bawang putih tidak optimal sehingga menurunkan angka produktivitas bawang putih. Penelitian ini bertujuan untuk pengembangan modul backend dari sistem pendukung keputusan spasial sebagai inovasi teknologi untuk mengevaluasi kesesuaian lahan serta menampilkan visualisasi data hasil evaluasi dalam bentuk gambar atau peta. Sistem dikembangkan dengan menggunakan framework Express.js dan basis data PostgreSQL dalam pembuatan REST API, serta metode Prototyping sebagai metode pengembangannya. Penelitian ini mengembangkan module backend untuk penentuan penanaman lahan bawang putih yang telah menghasilkan 12 URI API dan 1 scheduler yang telah berhasil diuji dengan menggunakan metode blackbox testing, Garlic is one of the horticultural commodities that has various benefits and widely consumed. The problem faced when you want to increase the production of qualified garlic is the difficulty of determining the appropriate land, because garlic cannot just grow anywhere. The inappropriateness of the land used will result in the suboptimal growth of garlic plants and reducing the productivity. This study focuses on the development of the backend module of a spatial decision support system as a technological innovation to evaluate the suitability of garlic land and display the visualization of the evaluation data in images or maps. The system is developed using the Express.js framework and PostgreSQL database in making the REST API, and also the Prototyping method as the development method. This study develops a backend module for determining garlic plantations which has produced 12 API URIs and 1 scheduler that has been successfully tested using the blackbox testing method
Keyword: backend, garlic, land suitability evaluation, REST API, spatial decision support system

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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