Judul: Green Supply Chain Management in Indonesian Crumb Rubber Factories: Designing Strategies towards Implementation.
Abstrak: Green supply chain management (GSCM) is a new technical innovation that has been touted to improve supply chain performance as well as minimize the environmental impacts. Unfortunately, this concept has not been entirely implemented in Indonesian rubber industries. The primary objective of this research were identify current green practices, to explore influencing factors and formulate green approach as well as select strategies to accelerate GSCM implementation in Indonesia’s crumb rubber factories (CRFs). The case studies were conducted in two private CRFs. The data were collected through semi-structure interviews with stakeholders, field observation, and examination of QMS documents. The GSCM model for CRFs was constructed, and the influencing factors were analyzed through thematic analysis through the lens of innovation diffusion theory. The Analytical Hierarchy Process was employed to prioritize the strategies. The findings suggest CRFs have not committed themselves to integrating the environmental management intentionally into the current production system; their motive of green efforts may be more to maximize efficiency and reduce the cost production rather than to be more environmental friendly. The results reveal that technological, organizational and environmental factors may influence the decision on GSCM adoption. In addition, green procurement which emphasizes increasing the quality of raw material from the rubber block supplier and educate farmers or supplier are the prioritized green approach to accelerate GSCM implementation. The practical results of this research provide valuable insights and guidelines for CRFs to integrate the green concepts into operational business strategy.
Keyword: Green Supply Chain Management, Innovation Adoption, Influencing factor, Crumb Rubber Factories

Judul: Designing an Implementation of Environmental Innovation Strategy towards Proactive Environmental Management: A Case Study in a Ribbed Smoked Sheet Rubber Factory in Central Java Province, Indonesia
Abstrak: Ribbed smoked sheet (RSS) is the second largest natural rubber product in Indonesia after crumb rubber. One of the problems associated with natural rubber processing is the environmental problems created by the use of large amounts of water, together with energy and chemicals that pollute the environment. An environmental innovation is considered as a strategy to address the environmental impacts better than the current end-of-pipe treatment by shifting it into more proactive environmental management. This research aims to explore solutions that are more environmentally friendly for the rubber industry. This study uses a qualitative Case Study approach on a small and exploratory scale, with data collected from interviews and observations. The results show that the environmental issues that are related to the factory’s daily operation are: water usage, accumulation of unprocessed material, the use of ammonia and the use of inorganic fertilizers. The obstacles in the way of environmental management are: financial issue, human resources, communities’ pressure, technological change and communication with environmental experts. Some proactive strategies to overcome these environmental issues are suggested namely: reuse of the wastewater and pollution prevention at sources. The results of this study also suggest conducting cooperation with research institutions or environmental experts especially for skills that cannot be controlled by the manager or employees in the company.
Keyword: Ribbed smoked sheet (RSS) rubber, proactive environmental strategies, environmental innovation

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.
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