Mowing lawns

The lawn-mowing analogy is also interesting in that up to a certain point there will be a linear speedup as mowers are added. This speedup occurs because the mowers do not interfere with each other s work and have efficient mechanisms for coordinating their efforts. The lawn-mowing problem exhibits very good data paraHeHsm. 

Adult moles are about 6 in (15 cm) long, with dense, dark brown fur. Females raise a litter of four or so per year. They do not eat plants, but can undermine them, disrupting growth, and their mounds make lawn-mowing difficult. 

In the United States, most cases have occurred in the summer, related to insect bites, and in the winter, related to hunters exposure to infected rabbit carcasses (40). Between 1990 and 2000, the CDC received an average of 124 case reports each year. Naturally occurring outbreaks have resulted from exposure to muskrat handling, tick bites, deerfly bites and lawn mowing or cutting brush (40). Exposures to contaminated drinking water and laboratory procedures have resulted in sporadic cases. 

The reactor consists simply of a horizontal tube, usually heated externally by means of a suitable furnace. Inside the tube is a screw agitator and conveyor, which is rotated slowly. A typical example is shown in Fig. 5.2. The agitator conveyor can take several forms the one illustrated consists of four long flights twisted with an even pitch about the shaft in a similar manner to the rotor of a lawn mowing machine. In other models two flights have been used instead of four. The flights are attached firmly to the shaft by means of struts, or studs in the case of a small model, in a direction such that the flat sides follow the contour of the cylinder in which they rotate. 

Karl,T., Fall, R., Jordan, A., Lindinger, W. (2001) On-line analysis of reactive VOCs from urban lawn mowing. Environmental Science Technology, 35, 2926-2931. 

Juana s lawn is 30 yards by 27 yards. Yesterday, Juana mowed 3 of the lawn. How many square yards are left to be mowed today ... 

Bart and Sam mow lawns at the same rate. If it takes Bart and Sam about 0.67 hours to mow... 

Kathy charges 7.50 per hour to mow a lawn. Sharon charges 1.5 times as much to do the same job. How much does Sharon charge to mow a lawn ... 

Patients with seasonal allergic rhinitis should keep windows closed and minimize time spent outdoors during pollen seasons. Filter masks can be worn while gardening or mowing the lawn. 

Barring these, lawn people have a number of specific obligations that allow them surprisingly little discretion. Mowing, watering, fertilizing, and applying... 

Mowing the lawn is fine, but all the other stuff I could do without. . . We certainly like the way it looks, but we wish it took a little bit less time... 

I think we d get a lot of complaints [if I didn t do yardwork]. Maybe you might not hear it, but everyone here keeps their lawn looking nice. If you were the only person who didn t mow. . . ... 

Collectively, this arrangement of lawn care begins to assemble itself into a kind of community pattern, or an ordered neighborhood rhythm. In a prominent example, the decision to mow on a particular day emerges as a collective group nondecision. Suzanne explained ... 

Several lawn managers spoke about the imperative to mow in time for the recent high school prom. Limousines came to the cul-de-sac to pick up several high school students, pictures were taken on front lawns, and everyone wanted their yards to look perfect. Frank described the scene ... 

My neighbor here [Frank] was having some problems with his job, so my son and I mowed his lawn for him. We didn t ask, we just mowed it. 

Whereas the above described behaviors are concerned with planting and mowing, chemical treatments are also greatly influenced by the neighbors. When we asked Suzanne why she continued her lawn chemical treatments even though her dog s paws were bleeding, she replied ... 

Countersuits sometimes occur, as where a Florida couple sued their home-owners association for harassment over deed restriction violations including spotty grass. The householders sodded their yard at the association s urging, nonetheless, prior to settlement of the suit. Courts too, have vindicated home-owners occasionally, as where a Massachusetts man who had not mowed his lawn in fourteen years, when faced with state sanitary code violations, was found not... 

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