Judul: Perancangan Sewage Treatment Plant (STP) sebagai  Implementasi Aspek Green Building pada Apartemen Samasta  Mahata Margonda Depok
Abstrak: Peningkatan pertumbuhan penduduk menyebabkan naiknya jumlah limbah cair domestik yang berasal dari kegiatan rumah tangga dan perkantoran. Konsep green building harus diterapkan terutama aspek konservasi air agar penggunaan air dapat berjalan dengan optimal. Salah satu upaya untuk mengolah air limbah domestik di Apartemen Samasta Mahata Margonda adalah penggunaan Sewage Treatment Plant (STP). Penelitian ini bertujuan merencanakan STP, melakukan identifikasi potensi penggunaan kembali air hasil pengolahan, serta melakukan penilaian green building kategori konservasi air. Konsentrasi akhir dari parameter air limbah BOD, COD, TSS, dan ammonia setelah melewati unit pengolahan sebesar 0,54 mg/L, 2,52 mg/L, 10,72 mg/L, dan 4,79 mg/L sehingga sudah memenuhi baku mutu standar aliran kelas 2 untuk penggunaan kembali air daur ulang. Penghematan air yang dapat dicapai untuk siram tanaman dan siram toilet adalah 56% atau 156,5 m3/hari dari total kebutuhan air bersih 276 m3/hari., Population growth due to urbanization has resulted in an increase in the amount of domestic liquid waste originating from household and office activities. The concept of green building must be applied, especially aspects of water conservation so that water utilization can run optimally. One of the efforts to treat domestic wastewater at the Samasta Mahata Margonda Apartment is to use a Sewage Treatment Plant (STP). This study aims to plan a STP, to identify the potential for reuse of treated water, and to conduct a green building assessment in the category of water conservation. The final concentrations of wastewater parameters BOD, COD, TSS, and Ammonia after passing through the treatment unit were 0,54 mg/L, 2,52 mg/L, 10,72 mg/L, and 4,79 mg/L so that they still meet the requirements quality standard for class 2 stream for reuse of recycled water. Water savings that can be achieved for watering plants and flushing toilets are 56% or 156,5 m3/day of the total clean water requirement of 276 m3/day.
Keyword: Greenship, konservasi air, limbah cair domestik, sewage treatment plant

Judul: The Design of Simple Water Reclaim System for Domestic Wastewater (Greywater)
Abstrak: Pertumbuhan populasi, perkembangan industri dan agrikultur, urbanisasi serta faktor kontaminasi dan kekeringan sumber, menjadi tantangan dalam pemenuhan kebutuhan air. Indonesia adalah negara kaya akan sumber air namun seiring dengan perkembangan pembangunan dan perubahan iklim, beberapa kota besar dilaporkan sedang mengalami krisis air dan penurunan kualitas air tanah. Cara kontruktif yang dapat dilakukan masyarakat dalam mendukung perbaikan kualitas sumber air salah satunya adalah usaha mengurangi dan mendaur ulang air limbah. Laporan statistik lingkungan hidup Indonesia tahun 2020 menyatakan lebih dari separuh limbah rumah tangga yang berasal dari mandi, mencuci, kegiatan dapur dialirkan ke selokan atau sungai. Perancangan sistem daur ulang air limbah rumah tangga (greywater) untuk penggunaan kembali dalam ruang lingkup pencucian kendaraan menggunakan tiga tahap secara berurutan yaitu koagulasi menggunakan koagulan alum, filtrasi dengan menggunakan metode multi media filter, dan disinfeksi menggunakan lampu ultraviolet. Pengujian paramer pH, oksigen terlarut, padatan terlarut, padatan tersuspensi dan kadar surfaktan akan dilakukan untuk menentukan kualitas air dengan standar baku yang sesuai dengan tujuan aplikasi air daur ulang. Kata kunci: air, daur ulang air, air limbah, greywater, filtrasi, koagulasi, disinfeksi, ultraviolet., Population growth, industrial and agricultural development, urbanization, and factors of contamination and sources' dryness are challenges in meeting water needs. Indonesia is a country with a lot of water resources. However, in population growth and climate change, several big cities are reportedly experiencing a water crisis and decreasing groundwater quality. One of the constructive ways that the community can support improving the quality of water sources is to reduce and recycle wastewater. The 2020 Indonesian Environmental Statistics report that more than half of household waste from bathing, washing, and kitchen activities goes into sewers, ditches, or rivers. The design of a household wastewater (greywater) reclaim system for application in the scope of vehicle washing uses three sequential stages: coagulation using alum coagulant, filtration using the multi-media filter method, and disinfection using an ultraviolet lamp. Tests for parameters of pH, dissolved oxygen, dissolved solids, suspended solids, and surfactant levels will be carried out to determine the quality of water with standards that are suitable for reclaimed water applications. Keywords: water, water reclaim, wastewater, greywater, filtration, coagulation, disinfection, ultraviolet.
Keyword: water, water reclaim, wastewater, greywater, filtration, coagulation, disinfection, ultraviolet

Judul: The Exploration of Discrete Logarithm over Finite Field GF(3m)
Abstrak: The security of many public~key algorithms is based on the problem of finding discrete logarithms. The generalized discrete logarithm problem is the following: given a finite cyclic group G of order n, a generator a of G, and an element fl E G, find the integer x, 0 ~ x ~ n - 1, such that 0: = fl. Algorithm for discrete logarithm problem focused on Menezes et al. (1997) that consist of exhaustive search algorithm, the baby-step giant-step algorithm, Pollard's rho algorithm, Pohlig-Hellman algorithm, and index-calculus algorithm. These algorithms are explorated to be used in discrete logarithm problem over finite field GF(3m ). The exploration also produces some algorithms, i.e. naif negative algorithm, baby-step mother-step algorithm, baby-step mother free-step algorithm, and baby-step free-step algorithm. All algorithms implemented using Maple 11. The Pohlig-Hellman and baby-step giant-step algorithms are efficient enough to be used in discrete logarithm problem over finite field GF(3m ) for m < 20.
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