JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. This content downloaded from 130.130.37.84 on FriThis paper describes an investigation into the delays experienced by ships waiting to pass through the Suez Canal. The main objective of the Suez Canal Authority (SCA) is to provide an attractive service to ship-operators, and in doing so to maximize the income received from canal tolls. Thus, SCA wishes to maximize the throughput of vessels, but also requires queueing delays to be held at an acceptable level. This paper quantifies both measures (throughput and delays), and illustrates how they are in conflict to some extent. The study is somewhat unusual in that it affords the opportunity to employ more than one OR technique (linear programming and queueing theory/simulation) in the quantification process. Some of the work reported was undertaken in a consultative capacity, and the remainder as part of an ongoing research programme.

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This chapter uses theBlack Hole as a metaphor for depression based on personal experience with the disease. Like a Black Hole, depression consumes and contorts time. Depression sucks an entire human life into itself, the chapter states. Nothing can withstand its relentless tug into sheer black nothingness; it is a force field of pure negativity, a Black Hole. Depression slows one’s sense of time as—in what is called ‘gravitational time dilation’—an object falling into a Black Hole appears to slow down as it approaches the event horizon, taking an infinite time to reach it. The chapter describes the condition when in a depressed state and says depression is an illness which seems to punish the sufferer with isolation, noting that isolation is different from loneliness and solitude. The chapter also suggests that animals are like the opposite of a Black Hole; for example, cats can be extremely important to someone who is depressed.