Judul: Pengetahuan Sikap dan Tindakan Petani dalam Pengelolaan OPT Jagung di Kecamatan Metro Selatan
Abstrak: Jagung merupakan komoditas penting sebagai bahan pangan pokok penghasil karbohidrat. Keberadaan organisme penganggu tanaman menjadi salah satu kendala dan faktor pembatas dalam budidaya jagung. Organisme yang dapat mengganggu tanaman mencakup hama, penyakit, dan gulma yang mampu menurunkan hasil produksi jagung. Penelitian bertujuan memperoleh informasi serta menganalisis karakterisitik, pengetahuan, sikap, dan tindakan petani dalam mengelola OPT jagung di Kecamatan Metro Selatan. Penelitian dilakukan pada bulan Oktober hingga Desember 2020. Lokasi pengamatan tersebar pada empat desa dengan setiap desa terdapat 50 tanaman contoh dan 15 petani responden. Pengumpulan data melalui metode wawancara menggunakan kuesioner terstuktur dengan jumlah responden sebanyak 60 petani dan pengamatan lapang menggunakan metode systematic random sampling. Data hasil penelitian diharapkan dapat memberikan informasi mengenai pengetahuan, sikap, dan tindakan petani dalam mengelola OPT jagung di Kecamatan Metro Selatan sehingga dapat menjadi bahan pertimbangan untuk rekomendasi penerapan PHT. Kata kunci: jagung, OPT, pengetahuan, sikap, tindakan, Corn is an important commodity as a staple food for producing carbohydrates. The existence of plant pests is one of the constraints and limiting factors in maize cultivation. Organisms that can disrupt crops include pests, diseases and weeds that can reduce corn production. The research aimed to obtain information and analyzed about the characteristics, knowledge, attitudes, and actions of farmers in managing maize plant pests in Metro Selatan District. The study was conducted from October to December 2020. The observation locations were spread across four villages with 50 sample plants in each village and 15 respondent farmers. The data was collected through interviews using a structured questionnaire with a total of 60 farmers as respondents and field observations using systematic random sampling method. The data from the assessment results are expected to provide information about the knowledge, attitudes and practice of farmers in managing maize plant pests in Metro Selatan District so that it can be considered as a recommendation for the application of IPM. Key words: attitude, corn, knowledge, plant pests, practice
Keyword: jagung, OPT, pengetahuan, sikap, tindakan

Judul: Knowledge, Attitudes, and Practices of Corn Farmers in the Management of Plant Pest Organism in Pesisir selatan District, West Sumatra
Abstrak: Serangan hama dan penyakit pada tanaman jagung mengakibatkan menurunnya produksi jagung bahkan dapat menyebabkan gagal panen. Penelitian ini bertujuan mengetahui pengetahuan, sikap, dan tindakan petani dalam budi daya jagung di Kabupaten Pesisir Selatan dan upaya menanggulangi OPT yang berkaitan dengan karakter petani dalam mengelola hama dan penyakit pada tanaman jagung. Penentuan responden dilakukan secara terpilih (purposive sampling) berdasarkan populasi penduduk yang bekerja sebagai petani jagung di kecamatan tersebut. Jumlah responden sebanyak 60 petani jagung dari tiga kecamatan yaitu Kecamatan Ranah Pesisir, Linggo Sari Baganti, dan Lengayang. Jenis dan sumber data yang digunakan dalam penelitian ini adalah data primer dan data sekunder. Data primer diperoleh melalui wawancara secara langsung dengan petani responden menggunakan panduan kuesioner terstruktur, sedangkan data sekunder diperoleh dari Badan Penyuluh Pertanian Kabupaten Pesisir Selatan. Hasil penelitian menunjukkan bahwa kurangnya pengetahuan petani terhadap PHT dan petani di Kabupaten Pesisir Selatan sangat bergantung pada penggunaan pestisida sintetik dalam mengelola OPT. Tindakan petani dalam mengelola hama dan penyakit juga dipengaruhi oleh faktor kebiasaan cara bertani secara turun temurun dan pengaruh dari petani lain. Perlu dilakukan kegiatan penyuluhan kepada petani mengenai cara pengelolaan OPT pada petani di Kabupaten Pesisir Selatan., Pests and diseases that attack corn crops resulted in a decrease in corn production and caused crop failure. This study aimed to determine the knowledge, attitudes, and Practices of corn farmers in Pesisir Selatan Regency related to Integrated Pest Management (IPM) on corn plants. Respondents were selected by purposive sampling based on the population as corn farmers in the sub-district. The respondents were 60 corn farmers from three sub-districts, namely Ranah Pesisir, Linggo Sari Baganti, and Lengayang sub-districts. The types and sources of data used in this study were primary and secondary data. Primary data were obtained through direct interviews with respondents using a structured questionnaire guidance, while secondary data were obtained from the Agricultural Extension Agency in Pesisir Selatan Regency. The research showed that there is a lack of knowledge of farmers on IPM, and the farmers in Pesisir Selatan Regency are very dependent on the use of synthetic pesticides in managing plant pests and deseases. Farmers' practices in managing pests and diseases were influenced by farming habits from generation to generation as well as other farmers. It is necessary to carry out outreach activities to farmers on how to manage pests for farmers in Pesisir Selatan Regency.
Keyword: corn pests and deseases, interview, IPM, survey

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: