Judul: Studi on Cleaner Production Oppurtunities in the Coconut Palm Sugar Processing (Case Study at Koperasi Wanita Srikandi, Purworejo)
Abstrak: Penelitian ini bertujuan untuk mengkaji penerapan produksi bersih pada industri gula semut kelapa. Tahapan penelitian meliputi identifikasi limbah, identifikasi alternatif produksi bersih, analisis kelayakan (teknis, finansial, dan lingkungan) pada penerapan produksi bersih, dan penentuan prioritas penerapan produksi bersih dengan metode MPE. Rantai proses produksi gula semut terdiri dari : (1) petani membuat gula semut dan gula cetak dari nira kelapa; (2) pengepul menerima gula semut dari petani dan membuat gula semut dari gula cetak; (3) pabrik pusat mengolah lebih lanjut gula semut dari pengepul. Hasil identifikasi limbah berupa kotoran dalam nira, abu sisa pembakaran, terbentuknya inti kristal, loss energy, kadar air gula semut tinggi, ampas parutan kelapa, dan ceceran gula. Alternatif produksi bersih yang direkomendasikan adalah pemanfaatan abu menjadi pupuk (PBP 0.0102 tahun dan B/C 98.11), mengganti bahan tungku (PBP 0.042 tahun dan B/C 240), modifikasi peralatan pengeringan (PBP 0.32 tahun dan B/C 21.73), mengganti bahan proses di petani gula cetak (PBP 0.026 tahun dan B/C 38.48), menyediakan mesin penepung gula semut (PBP 0.094 tahun dan B/C 36), dan perbaikan/modifikasi peralatan pengayakan, pengeringan, dan pengemasan (PBP 0.072 tahun dan B/C 66.4). Prioritas penerapan produksi bersih adalah perbaikan dan modifikasi peralatan pengayakan, pengeringan, dan pengemasan., This study aims to observe the application of cleaner production in coconut palm sugar industry. Stages of the research include waste identification, cleaner production alternative identification, feasibility analysis (technical, financial, and environmental) toward the application of cleaner production, and priority of cleaner production determined by Exponential Comparison Method (ECM). The cycles of coconut palm sugar production process are including: (1) farmers make coconut palm sugar and coconut sugar of nira water; (2) collector received coconut palm sugar from farmers and make it of coconut sugar; (3) main factory further process it from collector. Results of waste identification show debris in the sap, ash from combustion residue, formation of crystal core, loss energy, high coconut palm sugar water content, grated coconut pulp, and scattered sugar. The suggested alternatives are ash utilization into fertilizer (PBP 0.0102 years and B/C 98.11), replacing furnace materials (PBP 0.042 years and B/C 240), drying equipment modification (PBP 0.32 years and B/C 21.73), replacing materials in coconut sugar process (PBP 0.026 years and B/C 38.48), providing a pulverization machine (PBP 0.094 years and B/C 36), and repair/modification of filtering, drying, and packaging equipment (PBP 0.072 years and B/C 66.4). The priorities of cleaner production application are improvement and modification of filtering, drying, and packaging equipment.
Keyword: coconut palm sugar, cleaner production, ECM, financial feasibility, quick scan

Judul: Kajian Penerapan Produksi Bersih pada Agroindustri Minyak Goreng Kelapa (Studi Kasus di Koperasi Wanita Srikandi)
Abstrak: Penerapan produksi bersih pada agroindustri minyak goreng kelapa dilakukan untuk meminimalkan limbah dan mencegah kehilangan sumber daya. Penelitian ini bertujuan mengkaji peluang produksi bersih pada proses produksi minyak goreng kelapa. Tahapan penelitian mencakup analisis quick scan, identifikasi aliran material, energi dan limbah, penentuan alternatif produksi bersih, analisis kelayakan teknis, lingkungan dan finansial berupa benefit cost ratio (B/C ratio) serta payback period (PP), penentuan prioritas penerapan produksi bersih dengan metode perbandingan eksponensial. Rantai proses terdiri dari pembuatan minyak klentik di tingkat pemasok, kemudian dilanjutkan menjadi minyak goreng kelapa di tingkat pabrik. Alternatif produksi bersih pada tingkat pemasok adalah: (1) pengolahan nata de coco (B/C ratio 1,17 dan PP 0,74 tahun), (2) pengolahan pupuk kompos (B/C ratio 1,26 dan PP 0,29 tahun), serta (3) pembuatan maggot (B/C ratio 1,75 dan PP 0,45 tahun). Alternatif produksi bersih pada tingkat pabrik adalah: (1) penjadwalan produksi (B/C ratio 170 dan PP 0,05 bulan), (2) perbaikan SOP penuangan minyak (B/C ratio 4,55 dan PP 0,01 tahun), (3) water recycle (B/C ratio 2,99 dan PP 4,23 tahun), dan (4) penggantian instalasi pipa (B/C ratio 3,95 dan PP 0,05 tahun). Prioritas alternatif yang direkomendasikan pertama pengolahan pupuk kompos untuk tingkat pemasok dan penjadwalan produksi untuk tingkat pabrik., The application of cleaner production in the coconut cooking oil agroindustry carried out to minimize waste and prevent resources lost. This study aims to examine the opportunities for cleaner production in the process of coconut cooking oil. Research stages included quick scan analysis, identification of material flow, energy and waste, determination of cleaner production alternatives, technical, environmental and financial feasibility analysis as benefit cost ratio (B/C ratio) and payback period (PP), and determining priorities for the application of cleaner production with the exponential comparison method. The process chain consists of the crude coconut oil production at supplier level, then continuing into the coconut cooking oil at factory level. Alternative cleaner production at the suppliers level is (1) nata de coco processing (B/C ratio 1.17 and PP 0.74 years), (2) composting (B/C ratio 1.26 and PP 0.29 years), and (3) maggot production (B/C ratio 1.75 and PP 0.45 years). Alternative cleaner production at the factory level is (1) production scheduling (B/C ratio 170 and PP 0.05 months), (2) improvement in oil pouring techniques (B/C ratio 4.55 and PP 0.01 years), (3) water recycle (B/C ratio 2.99 and PP 4.23 years), and (4) pipe installation replacement (B/C ratio 3.95 and PP 0.05 years). The first recommended alternative priority was compost processing for supplier level and production scheduling for factory level.
Keyword: Cleaner production, coconut cooking oil, crude coconut oil

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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