...Light -Trees: 0pt ica I MuItica st ing for Improved Performance in Wavelength-Routed Networks Laxman H. Sahasrabuddhe and Biswanath Mukherjee University of California, Davis We introduce the concept o f a light-tree in a wavelength-routed optical network. A light-tree is a point-to-multipoint generalizat i o n o f a lightpath. A lightpath is a point-to-point all-optical wavelength channel connecti n g a t r a n s m i t t e r a t a s o u r c e n o d e t o a receiver a t a d e s t i n a t i o n n o d e . L i g h t p a t h communication can significantly reduce the number o f hops (or lightpaths) a packet has t o traverse; and this reduction can, in turn, significantly improve t h e network’s t h r o u g h p u t . We extend the lightpath concept by incorporating an optical multicasting capability at the r o u t i n g nodes i n order t o increase t h e logical connectivity o f t h e n e t w o r k a n d f u r t h e r decrease its hop distance. We refer t o such a point-to-multipoint extension as a light-tree. Light-trees can n o t only provide improved performance f o r unicast traffic, b u t they naturally can better support multicast traffic and broadcast traffic. In this study, w e shall concentrate o n the application and advantages o f light-trees t o unicast and broadcast traffic. We f o r m u l a t e t h e light-tree-based virtual t o p o l o g y design p r o b l e m as an o p t i m i z a t i o n problem w i t h one o f t w o possible objective functions: f o r a given traffic...
Words: 6430 - Pages: 26
...Arbol Grande, Guajiro Yo Oil on canvas 2001 180 x 200 cm/ 71 x 79 in Collection of the Artist The painting “Arbol Grande, Guajiro Yo” has a tree painted in the middle. The tree has many colorful leaves. There is a man sitting beneath the tree, who is smoking a cigar. Apparently, because of the smoking his doing, he is surrounded by a cloud of smoke. The man is wearing a hat and has a mustache on his face. Also, there are flowers on the bottom of the painting, this is the ground of the picture. The painting has many colors; for example, the leaves of the tree are green, yellow, orange, blue, and red, with an outline of black. The painting has a mixture of primary and secondary colors. The negative space of the painting has a lot of warm colors. The shapes in this painting is very organic. The whole scenery is very organic, because of the leave shapes and tree trunk shape. Also, the flowers at the bottom are organically shaped. The texture of the painting is an actual texture, very smooth as it looks. The tree trunk has gesture lines going down towards the end of the tree. There is a sense of repetition in the painting; the leaves on the tree are repeated in the same even way in each of the branches. The focal point of the painting is the tree. Last, The tree it is symmetrical, but the painting is really asymmetrical. I believe the artist is just trying to emphasize his love for the country side of Cuba...
Words: 959 - Pages: 4
...the clears out. The trees of Oirase stand like respected, insightful persons. Looking upward from the streambed where I stand, I see dark green leaves of August, loaded with life, stretching out from treetops and branches toward little fixes of blue sky. Nothing is more meriting commendation than a tree that has persevered. Excellence drawing closer godlikeness. Not a thing is absent. Flawlessness. Its trunk, gigantic. Its bark, thick. In Japanese it is called mizunara- - water oak. Its name gets from the expansive measure of water it stores. These trees develop to 100 feet in tallness; I am informed that their normal age is around 300 years. As I look upward, the consistent mumble of the mountain stream purifies my ears, punctuated every now and then with the peeping of fowls. Could there be a winged animal that does not sing? Could there be a tree that does not reach toward the sky? The tree stakes its exceptionally presence on only one thing. It needs just to completely show the force it has covered up inside. "I will carry on with my life! I will completely develop and idealize my life!" Without perplexity or faltering, glad, superb, the tree lives as it may be, consistent with itself. What's more, in the place where there is Oirase, such respectable trees line the streambeds in "green forests." And the name Aomori, the prefecture in which Oirase is found, signifies "green forests." It was my first visit to Aomori in 15 years. Summer,...
Words: 781 - Pages: 4
...accident. The image by Image Zoo also shows four different pathways leading into the one tree with branches that lead up into the sky. This picture shows the tree of life and how people can take different paths to experiences. I Measure Every Greif I Meet is a poem by Emily Dickinson that shows the strength a person needs to overcome grief in their lives. The strength comes within the individual and their surroundings. All three of these texts show that moving into the world involves different pathways to new experiences shown through different circumstances, problems and views. The image by Image Zoo reflects the idea that moving into the world involves different pathways. This image uses the rule of thirds and symbolism to bring attention to the four different pathways to the centre tree trunk. The rule of thirds draws central focus to the light coming from the tree. This light symbolises the light that is present through different pathways and journeys. Light symbolises the hope, possibilities that come with moving into the world. Even though each pathway comes to the same centre of light, it branches upwards into different pathways shown at the top of the tree trunk. The tree symbolises the “Tree of life” as the tree that brings possibility to the world, it gives life and experiences to everyone. This brings to the main point that moving into the world, shown metaphorically as the tree through the four different pathways to new experiences. Furthermore the position of characters...
Words: 2332 - Pages: 10
...THE TABLET With two hands grasping a thin stone tablet, Priam struggled to leap into the tree in complete silence. The branch swayed under his weight and rustled its leaves. Priam froze. Too much noise! Too much! He drew himself rigid. He refused to breathe. His heart hammered within his chest. He was close now, the tall gray mass peeking from the breaks in the leaves. His senses heightened as if he were hunting, but his knees trembled, his breaths shortened and grew louder against his will, and his instincts told him to flee. But Priam battled his instinct and sprang into the final tree. Priam perched upon a branch near the edge of the forest, eyes wide. Priam would not release his tablet, he never wished to abandon it from his strong grip, so he lowered himself onto the branch with one foot and swung the other over the branch until he sat with his legs dangling below him. The wall had not fled. And he could watch it. It was an enormous gray mass, climbing high into the sky so Priam could only see it through the canopy if he ventured to the thinnest edge of the forest. The wall never darted into its land of the Others, those that had driven his people into the forest long ago. Yet it threatened Priam, to flee, to disappear, to leave him alone. So Priam skulked toward it every time as not to awake it from its slumber. He had been successful today, and he could breathe again. As he stared at the wall, he lifted the tablet before him, his tongue wagging from the side of his mouth...
Words: 4027 - Pages: 17
...In botany, a tree is a perennial plant with an elongated stem, or trunk, supporting branches and leaves in most species. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In looser senses, the taller palms, the tree ferns, bananas and bamboos are also trees. Trees tend to be long-lived, some reaching several thousand years old. The tallest known tree, a coast redwood named Hyperion, stands 115.6 m (379 ft) high. Trees have been in existence on the Earth for 370 million years. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a woody trunk and branches as a way to tower above other plants to compete for sunlight. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typically contains woody tissue for strength, and vascular tissue to carry materials from one part of the tree to another. For most trees it is surrounded by a layer of bark which serves as a protective barrier. Below the ground, the roots branch and spread out widely; they serve to anchor the tree and extract moisture and nutrients from the soil. Above ground, the branches divide into smaller branches and shoots. The shoots typically bear leaves, which capture light energy and convert it into sugars by photosynthesis, providing the food for the tree's growth and development. Flowers and fruit...
Words: 402 - Pages: 2
...Fall - A Time Transition The fall season has many meanings for me. It is a time of transition that takes us from warm balmy days to the more harsh weather of winter. It's a time that takes us from the spectacle of nature in full bloom, to nature in hibernation. The signs of this transition are everywhere. The vivid colors of summer fade away, the color of the sky changes from deep blue to gray. The green fades from the grass and plants lose their blossoms. The leaves on the trees turn color, and lose their grip. Insects disappear. It's the tune of year that signifies the end of summer and vacations. No more picnics, swimming, baseball, tennis, and a myriad of other activities that most of us enjoy in the outdoors. It signals that during the next few months we will have to endure weather conditions that are not conducive to spending quality time outdoors enjoying nature. The knowledge of this seasonal period of transition awakens, in me, a more keen awareness of my surroundings than at any other time of year. The deeper appreciation comes from knowing that the good weather days are coming to an end. The fall season conjures up all sorts of analogies in my mind. For example, football and basketball games are divided into four quarters, a dollar is divided by four quarters, the calendar year is divided into four quarters, and the human life span might also be divided into four 20 year parts, assuming that we live an average of 80 years. In all these examples, the third period precedes...
Words: 1346 - Pages: 6
...I chose the Forest stream art piece for my paper. It is done by Harriet Dyer Adams in 1910. It is an oil on an 11x14 canvas. The contour of the lines in this painting really make it an exceptional piece to admire. The tree trunk and branches would be similar to any other tree had the artist not used great detail in her lines. The stream is flowing full in the beginning of the piece but as it goes in the distance it gets narrow. The artist also used great linear perspective with the way the trees are lined. They aren’t in a symmetrical line but staggered to give the realism of a real forest. The color used really depicts a full lush forest at its greenest. The light however seems that maybe the sun has sat or that the trees are so thick that little light shows through. Personally to me this is a personal place that the artist visited often and felt inspired enough to share it with everyone. To use the colors that she did seems to me that maybe she preferred it at a certain time of day. The green in the trees also says that she preferred this to the color of the fall leaves. The color of the stream was one of the concepts that pulled me in with this painting. The texture of the oil on the canvas also is a big part of this painting as it gives it almost a realistic feel that makes you want to touch it to see if it is real. The only thing that I could think about this painting that could potentially make it better for me is if it was on a bigger canvas. I absolutely adore this...
Words: 382 - Pages: 2
...Tree Common ash (Fraxinus excelsior), a broad-leaved tree European larch (Larix decidua), a coniferous tree Lepidodendron, an extinct lycophyte tree In botany, a tree is a plant with an elongated stem, or trunk, supporting leaves or branches. In some usages, the definition of a tree may be narrower, including only woody plants, only plants that are usable as lumber, only plants above a specified height or only perennial species. At its broadest, trees include the taller palms, the tree ferns, bananas and bamboo. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typically contains woody tissue for strength, and vascular tissue to carry materials from one part of the tree to another. For most trees it is surrounded by a layer of bark which serves as a protective barrier. Below the ground, the roots branch and spread out widely; they serve to anchor the tree and extract moisture and nutrients from the soil. Above ground, the branches divide into smaller branches and shoots. The shoots typically bear leaves, which capture light energy and convert it into chemical energy by photosynthesis, providing the food needed by the tree for its growth and development. Flowers and fruit may also be present, but some trees such as conifers instead have pollen cones and seed cones, and others such as tree ferns produce spores instead. Trees tend to be long-lived,[1] some reaching several thousand years old. The tallest known specimen on Earth...
Words: 7782 - Pages: 32
...Lemurs in Madagascar Melissa Cotham SCI/275 September 8, 2013 Stacey Laub Lemurs in Madagascar 1. What are Madagascar’s biomes? Discuss the major features of at least one of these biomes. Use the textbook for biome examples. Madagascar’s biggest biome is a tropical rainforest. A tropical rainforest biome primarily consists of warm weather, wet plants, and fungi ridden soils. There are three important layers of a tropical rainforest. The emergent layer, 50 m up; where vegetation grows in full sunlight. The canopy (middle) layer, 3-40 m up; provides protection of too harsh of sun to low light plants below. Finally the understory (ground level) where plants and animals only receive 2-3 percent of light from above. 2. What changes happening in Madagascar are posing challenges for lemurs? Give details about the sources, time scale, and types of change. Changes happening in Madagascar that are posing threats are the rapid environmental changes caused by humans. The changes that which humans are making are for the ‘sake-of-human-kind’. Although these changes may benefit humans, we are depleting the resources of the lemurs. For example the bamboo lemur (that eats only bamboo); will no longer be in existence, once all of the bamboo tress has been destroyed. 3. Which types of lemurs are adapting to the changes? Which types of lemurs are not adapting well? Why? The lemurs that are adapting well are the lemurs with the ability to thrive in secondary habitats...
Words: 550 - Pages: 3
...The Swan The Swan is about two boys named Ernie and Raymond who like to bully a boy named Peter Watson. They give Peter a hard time and put him through many dangerous ordeals. Characters There are three main characters in The Swan: Ernie, Raymond, and Peter. Ernie is portrayed as an evil and cruel boy who treats everyone badly and as an extremely violent person. Raymond is portrayed as cruel, like Ernie. Peter is portrayed as a boy who does well in school, and enjoys nature. Peter is also quiet and polite, loves music, and plays the piano well. He is also brave. Plot The Swan is a short story about Ernie and his friend Raymond who like to bully Peter Watson. Ernie gethis fifteenth birthday. His dad tells him to go kill some rabbits for supper. Ernie agrees, goes outside, and whistles for his friend Raymond to come outside. Raymond comes and they both shoot birds while heading to the rabbit field. When they get to the railway line they see Peter Watson, a boy whom they often bully. As a joke, Ernie and Raymond go over to Peter and point the gun at him and say, “Hands up!” Then, Raymond decides to tie Peter up on the railway tracks. Miraculously, Peter survives when the train comes over him by sinking into the ballast just barely enough so the train won’t hit him. Next, the two boys decide to throw Peter in the lake with his hands still tied. When they get to the lake, Ernie spots a duck on the lake and decides to shoot it instead. After he kills it, he orders...
Words: 587 - Pages: 3
...large forest full of plants. Lining the bark of numerous trees was moss as soft as feathers, and weeds springing out from cracks in the ground. Behind the cluster of bushes, which looked like they haven't been trimmed in years, there was an oak tree. Towering over anyone passing, the tree seemed as if it were thousands of feet tall. Its roots dug deep into the soil, reaching for every last drop of water. No one knew what magic lived inside this tree. And no one ever found out. Pilanu, the former goddess of Nature always enjoyed that story from the very moment her grandmother told her. She visioned it in her mind, and how she would use her goddess capabilities...
Words: 1810 - Pages: 8
...air we breathe every day. Trees are the one thing that help us survive and people view them as trivial objects more and more each day, underestimating the fact that our destruction of them could lead to a destruction of us. The leaves of trees can come in all different shapes and sizes. They form in bunches and give a sense of hair to the tree, adding a way to differentiate one tree from another. With the leaves, trees give us beauty. There’s not a prettier sight than mid-October, when all the tree’s leaves have changed colors and everywhere you turn there are different types of reds, oranges, yellows and more. The foliage is just one of the many reasons why trees are important, they give us natural beauty. They could be described as a painting in nature just without using brushes, paint or canvases. Tree’s trunks come in all different sizes, some thicker than others, giving protection in a way, to us humans and to animals. Since most trunks are big, hunters usually hide in between them when they’re looking for potential game. They wear camouflage to blend in with the trees, usually in patterns of different types of greens, browns and light mustard yellows. Speaking of game, trees also are the home to different kinds of wildlife, such as birds, squirrels, chipmunks, and more. Even insects use trees, such as honeybees, grubs, and ants. You can see the remnants of these animals in the trees bark, like holes from woodpeckers that were searching for its next...
Words: 980 - Pages: 4
...Although winter doesn't officially start for a while yet, it won't be too long before the ground freezes. By this time, your trees should be prepped for the winter. Although it's clear how winter can harm animal life, it's less clear to many people whether winter can harm trees. However, even without the destructive effects of ice storms, winter can harm trees in a number of ways. These tips will prevent this: Apply a Mulch Layer Freezing water expands. This property of water can damage tree roots when the temperature undergoes multiple freezing and thawing cycles. A layer of mulch acts as insulation that stabilizes the temperature of the roots and prevents freeze/thaw damage. It also retains moisture in the ground near the tree. You can...
Words: 343 - Pages: 2
...would always find myself behind the old oak tree in our back yard. This was my favorite spot. The thick trunk, like a bodyguard, protected me from the imaginary bullets that flew towards my body. I would lean against the hard bark and for some reason it was comforting to have something sturdy to lean on. It was dark brown, and every now and then a spider would nestle between the pieces of bark. Sometimes I would touch the tree to peek around the corner and my fingers would be sticky. I could never quite figure out why that was, but, nevertheless, I had the hardest time getting it off, a constant reminder of my tree. When my little brother, miguel and I weren't at "battle," I would lay beneath my oak tree and daydream. As I looked up I could see millions of branches protecting me from everything above. At the end of each branch were hundreds of more leaves that would gently catch the morning dew, and carefully allowed it to make its way to the grass. It was like thousands of stars in the sky as the sun caught the drops and allowed them to sparkle so brightly. This was my heaven, and as I lay there, I could feel the plush grass, like a snuggly old blanket, holding my body gently against the ground. Sometimes the grasshoppers would appear from around a blade of grass as if they were asking for approval to jump on my blanket. Every so often a leaf would jump off its branch to greet me as I sat. It would float through the air as light as feather and land softly on the grass. As...
Words: 385 - Pages: 2
