The long-term sustainability of modern agriculture is examined in an ecological context. As an aid to defining agriculture, animal agriculture, and sustainable agriculture, a broad overview of the structural and functional aspects of ecosystems is presented. The longterm sustainability of two corn production systems and four beef cattle production systems is then examined relative to energy out...

T article proposes a supporting framework for the implementation of the material control system POLCA (paired-cell overlapping loops of cards with authorization). The POLCA system is particularly appropriate for environments that involve highly variable demand and large product variety, which force small batch (or even one-of-a-kind) production. We propose a load-based version of the POLCA cont...

The Australian dollar is considered primarily a commodity-based currency. The high level of commodity-based exports in Australia’s trade balance is given as an explanation. Accordingly changes in world commodity prices should bring commensurate changes in the value of the Australian dollar, such that changes in world commodity prices are only partially transmitted to the Australian economy and ...

In this study, we investigate the strategy of increasing the production capacity temporarily by means of contingent contractual agreements. These agreements are viewed as capacity options. A continuous material flow production system that supplies materials to meet a random demand that switches randomly between a high level and a low level is considered. The production system does not have enou...