Abstract The Andean bear (Tremarctos ornatus) population density and relative abundance within the Chingaza Massif were assessed between September 2015 and May 2016. One hundred seventeen (117) camera traps were installed at 9 grids: 13 cameras per grid, each camera separated 750 m from the other; the sampling effort was 17,057 days-trap. Two thousand seven hundred eighty-four (2,784) native fauna records were obtained, 1,456 corresponding to mammals, 183 records for Andean bear specimens, 158 of them independent bear records (at least one hour between records), and 106 effective-independent bear records (also permitting individual recognition). Fifty-seven (57) Andean bear individuals were identified according to key external morphological features. Sixteen (16) adults were recaptured (12 males and 4 females), with a maximum mean distance of 27.22 km. Bears population density was 2.9 bears per 100 km². Based on this density and the buffer area of the sampling grids, we estimated an overall number of 122 bears in 4,215.15 km². The estimated density is the first for the species in Colombia and the lowest regarding previous reports from other countries. Thus, it is necessary to better understand how integral habitat quality and the anthropic impacts on habitat quality, availability, and connectivity may affect the Andean bear population densities in Colombia, as a useful tool for assessing populations` state and focus future conservation actions.

Resumen El concreto u hormigón es uno de los materiales más versátiles usados en la construcción. En la actualidad, se usa extensivamente en la industria, ya que puede ser moldeado de formas casi arbitrarias a través de moldes rígidos denominados encofrados. La manera en que se disponen los distintos elementos para formar el encofrado y las restricciones asociadas, genera retos computacionales interesantes que impactan directamente la industria de la construcción. En este artículo se propone la implementación de un modelo de restricciones que genera encofrados para muros rectilíneos usando formaletas modulares. Este enfoque se basa en la descomposición de muros y su representación en instancias del problema de cambio de monedas. Para este propósito, se utiliza el concepto de descomposición rectangular orientada para simplificar la entrada del problema y abordar la solución como un problema de optimización por restricciones (COP). Los experimentos con entradas de prueba ofrecen soluciones en tiempos inferiores a 200 segundos, cuyo resultado es un enfoque práctico y eficiente para la compleja tarea del diseño de encofrados.

Abstract Concrete is one of the most versatile materials used in construction. At present, it is extensively employed in the industry as it can be molded in almost any shape through rigid molds called formwork. The arrangement of the different elements that compose the formwork and its associated restrictions pose interesting computational challenges that directly impact the construction industry. In this article, we propose the implementation of a model with constraints that generates a formwork layout for rectilinear walls using modular forms. This approach is based on the decomposition of walls and their representation as instances of the change-making problem. For that purpose, we used the concept of oriented rectangular decomposition to simplify the problem input and address the solution as a Constraint Optimization Problem (COP). The experiments with test inputs provided solutions in less than 200 seconds, thus offering a practical and efficient approach to the complex task of formwork design.