Context and question: Network effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to have any benefit, time consuming engine switches must occur to make such connections or expensive dual mode engines must be used. This is mostly an issue for long distance trips, but many lines come to be dominated by through traffic from long-haul freight trains (usually running coal, ore, or containers to or from ports). In theory, these trains could enjoy dramatic savings through electrification, but it can be too costly to extend electrification to isolated areas, and unless an entire network is electrified, companies often find that they need to continue use of diesel trains even if sections are electrified. The increasing demand for container traffic which is more efficient when utilizing the double-stack car also has network effect issues with existing electrifications due to insufficient clearance of overhead electrical lines for these trains, but electrification can be built or modified to have sufficient clearance, at additional cost.
What has been removed because of the through traffic to electrified lines?
Answer: unanswerable
Context and question: Material transport elevators generally consist of an inclined plane on which a conveyor belt runs. The conveyor often includes partitions to ensure that the material moves forward. These elevators are often used in industrial and agricultural applications. When such mechanisms (or spiral screws or pneumatic transport) are used to elevate grain for storage in large vertical silos, the entire structure is called a grain elevator. Belt elevators are often used in docks for loading loose materials such as coal, iron ore and grain into the holds of bulk carriers
What are spiral screws used for?
Answer: to elevate grain for storage in large vertical silos
Context and question: The foundation trust invests undistributed assets, with the exclusive goal of maximizing the return on investment. As a result, its investments include companies that have been criticized for worsening poverty in the same developing countries where the foundation is attempting to relieve poverty. These include companies that pollute heavily and pharmaceutical companies that do not sell into the developing world. In response to press criticism, the foundation announced in 2007 a review of its investments to assess social responsibility. It subsequently cancelled the review and stood by its policy of investing for maximum return, while using voting rights to influence company practices.
When did the company decide to review its lack of sales in the developing world?
Answer:
unanswerable