Judul: Effect of Organic Fertilizer on Evapotranspiration, Water Use Efficiency, Growth and Yield of Red Spinach (Amaranthus tricolor) and Water Spinach (Ipomoea reptans)
Abstrak: Pemenuhan permintaan tanaman hortikultura dapat dilakukan melalui peningkatan produksi dengan mengetahui faktor iklim khususnya curah hujan, evapotranspirasi, serta kadar air tanah. Peningkatan produktivitas juga dapat dilakukan dengan pemberian pupuk organik pada tanaman. Penelitian bertujuan mengetahui pengaruh pupuk organik terhadap evapotranspirasi, efisiensi pemakaian air, pertumbuhan, dan hasil bayam merah (Amaranthus tricolor) dan kangkung (Ipomoea reptans). Percobaan dilakukan pada tanaman bayam merah dan tanaman kangkung secara terpisah. Kedua percobaan disusun dengan Rancangan Acak Kelompok (RAK) yang terdiri dari 3 perlakuan, yaitu tanpa pupuk: 0 ton ha-1 (P1), pupuk kandang: 10 ton ha-1 (P2) dan pupuk kompos organik: 10 ton ha-1 (P3) dengan 3 ulangan. Hasil penelitian menunjukkan bahwa pemberian perlakuan pupuk pada bayam merah memberikan pengaruh terhadap tinggi tanaman, jumlah daun, panjang akar, panjang daun, koefisien evapotranspirasi, kebutuhan air tanaman, serta efisiensi pemakaian air. Bobot segar tanaman bayam tertinggi yaitu 1866,7 g/3m2 dengan perlakuan pemberian pupuk kandang. Perlakuan pupuk pada kangkung berpengaruh pada tinggi tanaman, bobot segar sampel, bobot kering sampel, efisiensi pemakaian air, kadar air tanah. Pemberian pupuk organik juga memberikan pengaruh pada berat basah dan berat kering, khususnya pemberian pupuk kandang yang memiliki bobot segar paling tinggi yaitu 2166,7 g/3m2., Fulfilling the demand for horticultural crops can be done through increasing production by knowing climatic factors, especially rainfall, evapotranspiration, and soil water content. Increased productivity can also be done by applying organic fertilizer to plants. Research aims determine the effect of organic fertilizer on evapotranspiration, water use efficiency, growth, and yield of red spinach (Amaranthus tricolor) and water spinach (Ipomoea reptans). The experiment was carried out on red spinach and water spinach separately. Both experiments were arranged in a Randomized Block Design (RBD) consisting of 3 treatments, namely without fertilizer:0 ton ha-1 (P1), manure: 10 ton ha-1 (P2), and organic compost: 10 ton ha-1 (P3) with 3 replicates. The results showed thatfertilizer treatment on red spinach has an effect on plant height, number of leaves, root length, leaf length, evapotranspiration coefficient, plant water requirements, and water use efficiency. The highest fresh weight of spinach plants was 1866.7 g/3m2 with the treatment of manure. Fertilizer treatment on water spinach affects plant height, sample fresh weight, sample dry weight, water use efficiency, soil moisture content. The application of organic fertilizer also has an effect on the wet weight and dry weight, especially the application of manure which has the highest fresh weight of 2166.7 g/3m2.
Keyword: Compost, Evapotranspiration, Growth, Manure, Productivity

Judul: Growth, Yield and Efficiency of Water Use on Water Spinach and Red Amarath on Various Components of Planting Media in Pots
Abstrak: Kangkung dan bayam merah merupakan komoditas sayuran yang memiliki nilai komersial tinggi dan digemari masyarakat Indonesia, sehingga menyebabkan permintaan kedua komoditas tersebut meningkat. Perlu dilakukan usaha peningkatan produksi untuk jangka panjang. Salah satu upaya untuk meningkatkan produksi kangkung dan bayam merah melalui pengaturan media tanam dalam pot. Pengaturan media tumbuh tanaman dapat membuat pertumbuhan tanaman menjadi lebih baik dan mengefisiensikan pemakaian air. Sistem pengaturan media tanam yang ingin dikembangkan pada penelitian ini yaitu menggunakan media tanam tanah dan pupuk kandang dengan volume yang berbeda yaitu tanah (kontrol), 1:1, 1:2 dan 1:3 (tanah:pupuk kandang). Penelitian ini bertujuan untuk mengetahui pengaruh berbagai komponen media tanam terhadap pertumbuhan, produksi dan efisiensi pemakaian air dari penanaman kangkung dan bayam merah dalam pot. Penelitian dilaksanakan di Kelurahan Sukahati, Kecamatan Cibinong Bogor yang dimulai pada Februari hingga Maret 2022. Penelitian dilakukan berdasarkan rancangan acak kelompok lengkap (RAKL) dengan 3 ulangan dan 4 taraf perlakuan komponen media tanam pada masingmasing percobaan kangkung dan bayam merah. Hasil penelitian menunjukkan bahwa perlakuan media tanam dapat meningkatkan tinggi tanaman, jumlah daun, bobot segar dan bobot kering tanaman. Perlakuan tanah:pupuk kandang 1:3 menghasilkan tinggi tanaman, jumlah daun, bobot segar dan bobot kering tanaman lebih tinggi dibandingkan perlakuan lainnya. Perlakuan media tanam berpengaruh nyata terhadap evapotranspirasi total dan koefisien evapotranspirasi kangkung dan bayam merah yang ditunjukkan dengan perlakuan tanah:pupuk kandang 1:3 menghasilkan evapotranspirasi total dan koefisien evapotranspirasi lebih tinggi dan berpengaruh nyata terhadap efisiensi pemakaian air., Water spinach and red amaranth are vegetable commodities that have high commercial value and are favored by the people of Indonesia, causing the demand for these two commodities to increase. One of the efforts to increase water spinach and red amaranth production are by adjusting the planting media in the pots. By adjusting plant growth media, it can make plant growth better and make water use more efficient. The system for adjusting the planting media to be developed in this study is using soil and manure planting media with different components, namely soil (control), 1:1, 1:2 and 1:3 (soil: manure). This study aims to determine the effect of the composition of the growing media on the growth, production and efficiency of water use from planting water spinach and red amaranth in pots. This study aims to determine the effect of growing media componentson the growth, production and efficiency of water use from planting water spinach and red amaranth in pots. The research was carried out at Sukahati Urban Village, Cibinong Sub-Distric, Bogor District, starting from February to March 2022. This study was conducted based on a Completely Randomized Bock Design which consisted of 4 levels of treatment for the composition of the planting media for each experiment of water spinach and red amaranth. The results showed that the planting media treatment could increase plant height, number of leaves, wet weight and dry weight of the plant. The soil: manure 1:3 treatment resulted in higher plant height, number of leaves, wet weight and dry weight of plants compared to other treatments. Planting media treatment had a significant effect on total evapotranspiration and evapotranspiration coefficient of water spinach and red
Keyword: efficiency of water use, plant water requirements, planting media, manure

Judul: Analisis dan Implementasi Certificate Authorities (CA) pada Public Switched Telephone Network (PSTN)
Abstrak: Secure Telephone Protocol has ability to authenticate involved party and keep the secrecy of the message sent over the protocol. The secrecy of the message archieved by using symmetric key cryptographic scheme, and authentication archieved using public key cryptographic scheme. One of several party involved in the protocol and hold an important function called Certificate Authorities or CA. CA responsible for generating public key pair for other party involved in the protocol. When CA generates public key pair, several primitive cryptographic scheme used for guarantee the security of the key. Two of them are hash function SHA-1 and El-Gamal public key scheme embedded in Digital Signature Algorithm scheme. The prototype implementing the scheme above developed using Java programming language with JCE addition from Bauncy Castle. The analysis towards implemented prototype indicates that the prototype still has some flaws to be implemented in real world.
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