10,870 research outputs found
Cost-Sensitive Decision Trees with Completion Time Requirements
No full textIn many classification tasks, managing costs and completion times are the main concerns. In this paper, we assume that the completion time for classifying an instance is determined by its class label, and that a late penalty cost is incurred if the deadline is not met. This time requirement enriches the classification problem but posts a challenge to developing a solution algorithm. We propose an innovative approach for the decision tree induction, which produces multiple candidate trees by allowing more than one splitting attribute at each node. The user can specify the maximum number of candidate trees to control the computational efforts required to produce the final solution. In the tree-induction process, an allocation scheme is used to dynamically distribute the given number of candidate trees to splitting attributes according to their estimated contributions to cost reduction. The algorithm finds the final tree by backtracking. An extensive experiment shows that the algorithm outperforms the top-down heuristic and can effectively obtain the optimal or near-optimal decision trees without an excessive computation time.classification, decision tree, cost and time sensitive learning, late penalty
Two Joshua Trees, [s.d.]
No full textPhotograph of two Joshua trees, [s.d]. Two trees with thick bark and branches stand rooted in sandy dirt while small shrubs cover the ground. Spiky round balls of leaves are attached to the ends of the branches while all the branches seem to drupe downwards. More Joshua trees can be seen in the distance. Photoprint reads: "This is what our paper money is made from"
Palm trees in Eastlake Park (later Lincoln Park), [s.d.]
No full textPhotograph of palm trees in Eastlake Park (later Lincoln Park), [s.d.]. About four park benches are situated between two palms a few yards away. The benches, three of them facing one, are spaced out to allow a walkway between them. The ground appears to be dry and littered with a few scattered leaves. Patches of grass (or weed?) sparsely cover the ground. Other trees are visible in the background.; "Lincoln Park (formerly East Lake Park), which was a major tourist destination, boasts a nearby zoo and an alligator farm in addition to boating and lavish gardens in the early part of the century. Today, the park is best known as the location of Plaza de la Raza, established in 1970 in response to a city plan to demolish the historic boathouse, the organization has become the leading multidisciplinary cultural arts center for Latinos in Los Angeles." -- unknown author
What do they like about trees?: Adding local voices to urban forest design and planning
No full textLocal preferences and priorities for trees and greenspaces are important considerations when planning and designing a community's urban forest. Local residents can provide insight into place-specific contexts such as local aesthetic preferences, social systems, cultures, and attitudes to inform appropriate design responses. Residents also inform researchers of key local issues that may impact urban forest configurations, and may differ from expert opinions. This paper reports on a case study from a suburban community in Canada that used a combination of methods to reveal new, place-based information to inform more contextual design for a community's future urban forest. Results reveal that the current urban forest in the community does not reflect the participants’ preferences and differs from experts’ priorities. The findings suggest issues that should be considered in future urban forest design and planning processes
A Generic Translation from Case Trees to Eliminators
No full textDependently-typed languages allow one to guarantee correctness of a program by providing formal proofs. The type checkers of such languages elaborate the user-friendly high-level surface language to a small and fully explicit core language. A lot of trust is put into this elaboration process, even though it is rarely verified. One such elaboration is elaborating dependent pattern matching to the low-level construction of eliminators. This elaboration is done in two steps. First, the function defined by dependent pattern matching is translated into a case tree, which can then be further translated to eliminators. We present a generic, well-typed implementation of this second step in Agda, without the use of metaprogramming and unsafe transformations, by providing a type-safe, correct-by construction, generic definition of case trees and an evaluation function that, given an interpretation of such a case tree and an interpretation of the telescope of function arguments, evaluates the output term of the function using only eliminators. We only allow case splits on variables from a fixed universe of data type descriptions, for which we use techniques like basic analysis and specialization by unification.https://github.com/klieverse/case-trees-to-eliminators Formalization of this thesis in Agda.Computer Scienc
View of the flowers and palm trees in Eastlake Park (later known as Lincoln Park), [s.d.].
No full textPhotograph of a view of the flowers and palm trees in Eastlake Park (later known as Lincoln Park), [s.d.]. In the foreground is a beautiful garden of flowers surrounded by a short wire-mesh fence. A footpath circles around this garden and branches off into a straight path that leads to a bench in the distance. Nearby on the footpath are two benches facing each other. On the grass behind the benches and all the way down to the bench at the end of the footpath is a column of palm trees (one on each side of the footpath). Other trees are visible behind the column of palm trees as well as in the distance.; "Lincoln Park (formerly East Lake Park), which was a major tourist destination, boasts a nearby zoo and an alligator farm in addition to boating and lavish gardens in the early part of the century. Today, the park is best known as the location of Plaza de la Raza, established in 1970 in response to a city plan to demolish the historic boathouse, the organization has become the leading multidisciplinary cultural arts center for Latinos in Los Angeles." -- unknown author
Tall redwood trees (Sempervirous), Santa Cruz, ca.1900
No full textPhotograph of tall redwood trees (Sempervirous), Santa Cruz, ca.1900. A mat(?) is lied between two of the trees. A sign is posted on one of the trees (at left)
California club, showing person and trees near base of building, [s.d.]
No full textPhotograph of California club, showing person and trees near base of building, [s.d.]. In the extreme foreground at right, a utility pole and wires can be seen. In the background to the left, a group of trees can be seen near lampposts. Walking along a road near the trees, a person can be seen. Behind the trees at center, a large building can be seen. The base of the building is wide and rectangular. Two smaller rectangular sections can be seen placed upon the base. At the top of the building, four chimney stacks can be seen. Along the side of the building, numerous windows and small palm trees in vases are visible above the base. In the extreme background, more buildings can be seen. To the far right, a sign reads: "Consumers Credit Co. Auto Loans"
Line of palm trees in South Park, [s.d.]
No full textPhotograph of a line of palm trees in South Park, [s.d.]. A wall of large palm trees extends into the background from the right, cutting across a well-mown swath of grass. A small stretch of paved walkway is visible in the extreme foreground, surrounding a flower bed to the left. More trees are visible in the distance at center
Surface phytoplankton pigment distributions in the Atlantic Ocean: an assessment of basin scale variability between 50N and 50S
No full textWe present an overview of the spatial distributions of phytoplankton pigments along transects between the UK and the Falkland Islands. These studies, undertaken as a component of the UK Atlantic Meridional Transect (AMT) programme, provided the first post-launch validation data for the NASA SeaWiFS satellite. Pigment data are used to characterise basin-scale variations in phytoplankton biomass and community composition over 100° of latitude, and to compliment the definition of hydrographic oceanic provinces. A summary of the key pigment characteristics of each province is presented.Concentrations of total chlorophyll a (totCHLa = chlorophyll a, CHLa + divinyl CHLa, dvCHLa) were greatest in high latitude temperate waters (>37°N and >35°S), and in the Canary Current Upwelling system. In these regions, the total carotenoid (totCAR) budget was dominated by photosynthetic carotenoids (PSCs). High accessory pigment diversity was observed of which fucoxanthin (FUC), 19'–hexanoyloxyfucoxanthin (HEX), and diadinoxanthin (DIAD) were most abundant, indicating proliferation of large eukaryotes and nanoflagellates. In contrast, tropical and sub-tropical waters exhibited concentrations of totCHLa below 500 ng l?1, with the North Atlantic Sub-tropical East gyre (NASE, 26.7–35°N), South Equatorial Current (SeqC, 7–14.6°S) and South Atlantic tropical Gyre (SATG, 14.6–26°S) characterised by totCHLa of <100 ng?1. These waters exhibited relatively limited pigment diversity, and the totCAR budget was dominated by photoprotecting pigments (PPCs) of which zeaxanthin (ZEA), a marker of prokaryotes (cyanobacteria and prochlorophytes), was most abundant. DvCHLa, a marker of prochlorophytes was detected in waters at temperatures >15°C, and between the extremes of 48°N and 42°S. DvCHLa accounted for up to two-thirds of totCHLa in oligotrophic provinces demonstrating the importance of prochlorophytes to oceanic biomass.Overall, HEX was the dominant PSC, contributing up to 75% of totCAR. HEX always represented >2% of totCAR and was the only truly ubiquitous carotenoid. Since HEX is a chemotaxonomic marker of prymnesiophytes, this observation reflects the truly cosmopolitan distribution of this algal class. ZEA was found to be the most abundant PPC contributing more than one third of the total carotenoid budget in each transect.Greatest seasonality was observed in highly productive waters at high latitudes and in shallow continental shelf waters and attributed to proliferation of large eukaryotes during spring. Concentrations of the prokaryote pigments (ZEA + dvCHLa) also exhibited some seasonality, with elevated concentrations throughout most of the transect during Northern Hemisphere spring
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