Judul: Green Productivity as an Approach to Address the Environmental Problem of Leather Tanning SMEs in Yogyakarta, Indonesia
Abstrak: The leather tanning industry is a most promising industry in Yogyakarta. However, the industry faces environmental problems due to poor environmental management practices. This study develops strategies to address the environmental issues of the impact of leather tanning SMEs in Yogyakarta. It identifies opportunities for improvement based on Green Productivity (GP) approach, and obstacles to formulating strategies for enhancing environmental performance. This study uses a Case Study approach using field observations and interviews with a number of leather tanning SMEs and industry experts. The results show that the SMEs in this sector adopt only a limited level of environmental practices. A set of GP options is proposed based on the observational evidence and expert judgements. Using an Analytic Hierarchy Process (AHP), a priority selected is to optimize the production processes of leather tanning SMEs. This study found that internal obstacles to green adoption included insufficient resources and infrastructure, low-skilled human resources, poor financial capability, lack of awareness, and poor organizational strategies. The external obstacles are significant and include inadequate law enforcement and government support, a small and limited market segment, and the lack of available green chemicals. These contribute toward poor environmental practices. To deal with these problems, this research proposes eight strategies for tackling the obstacles that prevent the implementation of leather tanning green practices. The strategies are divided into internal and collaborative. The internal strategies include encouraging enhanced product development processes and promote proactive and innovative strategies. Regarding their limitations, SMEs need stakeholder assistance to help solve their issues. A collaborative approach is crucial. Developing low-cost green technologies through R&D activities, developing best practice guidance and promoting its implementation, providing adequate facilities and machinery, identifying suitable suppliers to supply green chemicals, intensifying knowledge transfer of good environmental management, and establish a punishment and reward system are proposed for addressing the issues.
Keyword: green productivity, leather SMEs, AHP, SWOT

Judul: Kajian Implementasi Produksi Bersih di Industri Penyamakan Kulit (Kasus Desa Cibuluh, Kecamatan Bogor Utara)
Abstrak: Leather tanning industries are industries that process animal skin to produce finish leather product by using many stages of process. Every stage of the process will generate a large amount of wastes, either liquid or solid wastes. If the waste is not treated properly, it will cause environmental pollution. Implementation of cleaner production strategy can be used to solve this problem. This research studies the potentials of cleaner production application and alternative of cleaner production strategy in order to develop environmental friendly tanning industry in Cibuluh. The method used was process identification, waste sourch identification, and cleaner production analysis strategy. The cleaner production alternatives which are potential to be applied are design of installation wastewater to IPAL with pipe from molen machine, reuse wastewater from pre soaking process for the next batch, separation wastewater from hair and flesh, processing of fleshing waste for fat, and recycle chromium from tanning wastewater. Based on the priority alternative, three options were selected, namely recycle chromium from tanning wastewater, separation wastewater from hair and flesh, and reuse wastewater from pre soaking process for the next batch. The total investment of these option is Rp 2,059,500,- with pay back period (PBP) of 0.17 month. The Analitycal Hierarchy Process (AHP) analysis result shows that industrial policy is the most important factor to minimize waste product of tanning industry. The priority of cleaner production program from AHP analysis is recycle chromium from tanning wastewater which is consistent to that resulted from field study.
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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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