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The African rubber boom, which lasted from 1890 to 1913, had a significant economic and political impact on many parts of Africa. While the broad outlines of the boom were determined by the world market, the numerous local and regional variations were influenced more by the depletion of the rubber supplies. The factors that influenced the depletion varied according to whether the region in question was a free trade area or a concession area.The end of the notorious concession companies in the Congo Independent State has generally been attributed to the efforts of English and Belgian reformers. Recent research on Abir, a major Congo concession company, has revealed that attempts at reform were ineffective, and that exhaustion of the of the rubber supplies had caused the rubber system in the Abir concession to break down by 1906, when serious debate on the Congo question was just beginning in Europe.The article shows how the Abir system, which was designed to constantly increase production, led to depletion of the rubber resources. When the depleted areas merged, the territory passed into a period of crisis during which Abir lost control and production plummeted. Production figures for other Congo concession companies suggest that events in their territories followed a similar pattern.

Disassembly plays a key role in a life-cycle-based economy since it enables the recovery of resources in product and material cycles. In order to set up future disassembly plants, various problems have to be solved in advance. This includes varying quantities as well as a wide range of product types and states. A partly automated disassembly system could adapt to a large variety of products and different degrees of devaluation. Differences between a given disassembly plan and the actual situation at the shop floor require a highly flexible control system. High flexibility can be achieved by rapid rearrangement of transport processes and disassembly operations based on the actual system conditions in relation to requested disassembly tasks. This requires an adaptive control based on modules. Additionally, the ability to exchange control modules, variables, and parameters online will be required. Consequently, at the device level, robots have to be adaptive to new requirements in cooperation with the cell controller. Modularized program blocks and online exchanges are also required for the robot controller.Note to Practitioners-In this paper, a concept for the generation of flexible control sequences for a partly automated disassembly system has been presented, which can cope with the disassembly object variety, different product conditions, as well as product amounts. Washing machines were chosen as an example for the product group domestic appliances. The approach is directed at the planning level and cell-control level. The concept for the generation of disassembly control sequences consists of a function unit for the disassembly control system. The procedure, which will be implemented in the module, considers the availability of disassembly tools and the technological feasibility of disassembly processes and tools. A modular control sequence will be generated by the programmed function unit. The developed control concept can also be applied for very small lot-sized manufacturing and assembly tasks.

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