First paragraph: Bumblebees belong to the genus Bombus, which comprises about 250 species, largely confined to the temperate Northern Hemisphere. They are wholly dependent on flowers for their energetic and developmental requirements. Most are social species, with nest sizes varying from 50 to 400 workers. As such, they have attracted considerable attention regarding their role as pollinators. There is a growing body of evidence that bumblebees have declined in Europe, North America and Asia in recent decades because of multiple causes probably including habitat loss, impacts of pesticides, competition from non- native species and the introduction of non-native diseases (Goulson, Lye & Darvill 2008a; Williams & Osborne 2009). Recent health problems affecting honeybees and a perception that other pollinators may be declining has led to serious concern that we might be facing a global ‘pollination crisis' affecting pollination of crops and wildflowers (e.g. Aizen & Harder 200

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Dynamic simulation and applications of a novel, continuous-fed, constant level modified sequencing batch reactor for biological nutrient removal are presented. The underlying mathematical model and practical applications of the simulation are discussed. Case studies are presented to illustrate the applications as well as the flexibility of the system in meeting different wastewater treatment requirements. Operation experience from full-scale wastewater treatment plant demonstrates the reliability, ease of operation and high efficiency of the system. Average BOD5, total nitrogen, total phosphorus and TSS removals of 97, 81, 88 and 94% are achieved respectively on an annual basis with little operator attention. Consistently high waste activated sludge concentrations are demonstrated, averaging approximately 20,000 mg/L.

Introduction Maintenance standardization and optimization are critical factors in the success of any pro-active maintenance organization. Continuing developments in maintenance practices have brought a growing awareness that the implementation of a well-planned Reliability Based Maintenance Strategy (RBMS) can result in reduced unplanned downtime for drilling rigs and equipment. Still, the most significant development for maintenance management in recent years has not been the wealth of new techniques and practices. Instead, it has been the gradual acceptance that maintenance need not be a necessary evil, but that a carefully planned, information-based maintenance strategy can be a fundamental factor in the success of the organization. Pro-active maintenance practitioners are familiar with the term "the right amount at the right time", but what is the right amount, and when is the right time? The real challenge to the empowered maintenance professional, is to convert textbook theory into workable practice, and to do that, he must have the right tools for the job. Reliability Based Maintenance can achieve its full potential only if the data that are used to provide the basis for critical planning decisions are accurate and consistent. The importance of good data cannot be overstated. Maintenance optimization is a painstaking, iterative process of equipment failure analysis, and re -alignment of schedules and practices in order to minimize those failures. Poor quality data will always result in an inefficient and ineffective strategy. Measurement of the effectiveness of the maintenance strategy is an essential component in this process of continuous improvement. Accurate and meaningful performance indicators must be established at an early stage and at all levels of the organization. Whether you measure the reliability of your equipment using Mean Time Between Failures or by Weibull distribution, there can be no better maintenance performance indicator for the drilling industry than rig downtime. The GlobalSantaFe RMS II system provides all the tools that are necessary to implement and monitor a Reliability Based Maintenance Strategy, and much of its functionality has been designed specifically for that purpose. The data for any one piece of equipment, when considered in isolation, will always be suspect. However, that same data, when combined and analyzed across the entire fleet, provide us with a much more powerful tool, and we can have a much greater degree of confidence in its accuracy. Maintenance Standardization The requirement to standardize maintenance planning across the fleet is essential if the reliability data is to be accurate. This is accomplished in RMS II by means of the Equipment Data Library, which is designed to hold the global maintenance plans, critical measurements, and specifications for all makes and models of equipment owned by the company. The information held in this library is control led from GlobalSantaFe's head office. When a new rig equipment database is set up, the relevant information from the data library is downloaded to that database.