The south end of Vashon Island is quieter than the business district, making it a lovely place to take a calming walk with your family. Burton Acres park offers a short but fulfilling hike. The 64-acre park features more than 1.2 miles of trails to explore on a loop route. Continue reading
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We analyzed all algorithms but show results only for RankEdge in the main text because Weighted rarely converged onto a single path, and thus did not satisfy our second performance metric. It also did not maintain trails in the absence of a break. These results are described in detail below. Also, see Table 2 and Supplement for analysis of the additional non-linear algorithms.
To demonstrate the utility of this algorithm in a real-world scenario, we applied the RankEdge algorithm to repair networks in a human-designed transport network (Fig. 5). We downloaded the network depicting the major roads (edges) connecting intersections (nodes) in the international E-Road in Europe63 (Methods). We removed an edge from an existing path between two nodes and ran the RankEdge algorithm to repair the simulated closure. The RankEdge algorithm achieved a success rate of 70%, indicating that the turtle ant algorithm can also repair breaks in real-world topologies. This shows how distributed solutions may be useful for new application domains, such as for swarm robotics or molecular robots64,65,66,67 in remote environments, when centralized or global positioning systems may not be as effective.
Here we consider whether the same algorithm used to repair a path can also keep a path intact when it is not broken. This is important because if different algorithms were used to maintain trails versus repair trails, then the turtle ants would need some signal to toggle between different methods for choosing among candidate edges, depending on the context. We found that a single algorithm, RankEdge, is capable of maintaining trails and responding to breaks.
The RankEdge algorithm is parsimonious, capable of both maintaining trails and repairing breaks to trails using the same underlying logic. Observed ants encounter diverse situations analogous to breaks in the ongoing maintenance of trails. We find that a single algorithm can solve two diverse problems without requiring the additional complexity of a signal that distinguishes such situations from a rupture in the trail. How each path is established originally is an interesting yet distinct question. Paths are not always the shortest globally, and the physical structure of edges in the canopy appears to affect how these paths are selected.
Views of the creek are frequent along the trails, and much of the creek bank is sandy like a beach. Waterfowl like ducks, geese and Great Blue Herons can be seen swimming or fishing in the creek, and other water-loving animals like frogs, deer, otters, fox and muskrat are spied mostly in the morning or at dusk. The fur-pup's ears and nose will be twitching with excitement at the wildlife smorgasbord!
All trailheads for currently existing trails lie at Lindbergh Drive where it passes under Highway 85. Street parking is available near the access points. While the total trail miles today are only about 6, the Conservancy's plans to extend the routes to Buckhead and Emory, along with forging connector paths, will amass enough additional miles to meet or exceed 31 miles, connecting many more green areas and communities.
The pupular North and South Confluence Trails are about 1.5 miles in length, with an ascent of about 115 feet. This gentle incline allows hikers and their pups to comfortably view the creek from bridges arching above it, or view the planned evolution from a tangled view of vines, hedges, weeds and underbrush to native shrubs, hardwoods and pines. Butterflies and bees flit here and there in the spring and summer, along with many songbirds above. Occasionally glimpses of the Atlanta skyline come into view as well.
Along with 4 other, shorter trails, the South Fork Conservancy has taken what was once an unusable part of the city and made it accessible and enjoyable for all humans and their fur-babies. Bring anything you may need for a pawrific afternoon stroll, including water and clean up bags.
When the family attended a Cross Country Ski Areas Association conference in California, they discovered the magic of groomed trails. John knew a perfect set of rolling knolls, with a couple of ancient logging roads winding through them, on Bobcat Pass, outside of Red River. They opened Enchanted Forest Cross Country Ski Area there in 1985.
At Enchanted Forest, some sections of trail were relatively clear, and work moved quickly. The trails were too narrow for a bulldozer, so every tree had to be sawed into three-foot chunks and tossed out of the way by hand. They recruited volunteers every weekend, sending out up to 12 at a time.
, cannot be trapped in its own web. While rare, a careless spider can be caught in the net it constructed to capture prey. The fact it happens so seldom is a mystery that scientists have yet to solve. One theory suggests that the nimble creatures avoid becoming tangled in their webs by dancing lightly across the sticky strands with only the hairs on the tips of their legs making contact with their clever traps.
The trail begins along the berm beside Mud Lake. After a rather uninspiring 3 km (you can mountain bike this part) the trail narrows and enters trees where tangled roots twist across the path and you breathe in the smells of damp earth and moss.
Outside, shabby frame houses ran down hill to the angry green riverwhere drifting ice-floes shocked. Dark woods rolled up the other bankand trails of mist crawled among the pines. Patches of snow checkeredthe rocks above; in the distance a white range glimmered against leadencloud. The settlement looked strangely desolate in the driving rain,but the small ugly houses were the last Jim's party would see for long.The wagon road ended there and a very rough pack trail led into thewilds. There was another hotel, to which the men Jim had engaged hadgone.
In order to banish his drowsiness, Jim gave himself up to wanderingmemories. He knew the North, where he had risked and endured much. Hehad seen the tangled pines snap under their load of snow and go down inrows before the Arctic gales; he had watched the ice break up and theliberated floods hurl the floes into the forest. He had crossed thebarren tundra where only moss can live and the shallow bog that steamsin summer rests on frozen soil.
They ate quickly and when the meal was over Jim and Carrie set offwhile Jake went to work. It was not easy to push through the tangledbush, and now and then Jim was forced to clear a path with his ax.After a time he stopped behind a trunk and touched Carrie, who saw ananimal leap out from the gloom. It cleared a big fallen branch with aflying bound, vanished almost silently in a brake of tall fern, andshooting out with forelegs bent sprang across a thicket. Carriethought it hardly touched the ground. It was wonderfully swift andgraceful, and although the forest was choked with undergrowth androtting logs all was very quiet when the animal vanished.
The spur commanded the valley and the fire that had run through thewoods below. In the foreground a wall of tossing flame threw outclouds of sparks, and leaping up here and there, ran in yellow trailsto the top of the tall firs. It advanced slowly, with an angry roar,licking up the dry brush and branches before the big trunks caught. Infront they were hung with streamers of flame, farther off they glowedred, and in the distance smoldering rampikes towered above a wide beltof ash. Now and then one leaned and fell, and showers of sparks shotup as if the log had exploded.
The tangled brush had vanished and wet ashes covered the ground.Half-burned logs lay about, and here and there small trees, leaning atsharp angles with blackened branches locked, held each other up. Inplaces, big charred rampikes stood in rows like colonnades. The nearerrows looked black; farther off they shone in the rain with a curioussilver gleam. The fire had helped to clear the ground, but wet menwere at work with axes and saws.
She studied him and Jake while she talked to Mrs. Winter. Jim seldomwore conventional evening clothes, but he had put on an Americandinner-jacket. He and his comrade were strangely agile; theirmovements were quick, their step was light, like a cat's, and she notedhow they lifted their feet. She did not know the prospector gets thehabit by walking through tangled bush and across rough stones. Theyhad a suppleness that came from using the long ax, and toil in thewilds had given them a fine-drawn look. In some ways both were modern,but in some they belonged to the past, when the fortress peels werebuilt and the marsh-men fought the Scots. 2ff7e9595c
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