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Ridge Coarsening in Evaporatively Driven Climbing FilmsLamb, Peter 01 May 2003 (has links)
In thin-film mixtures of alcohol and water, differences in evaporation rates and surface tensions between the two liquids can cause what is known as Marangoni convection within the fluid. This can lead to the formation of interesting instabilities on the surface of the film, such as the commonly observed “wine tears” phenomenon. Similar instabilities are observed when an inclined plate is immersed in a water alcohol reservoir. In addition to the tears, small ridges can be observed where the thin-film along the side of the plate rejoins the larger reservoir. These ridges slowly drift to the side and merge with other ridges, coarsening into larger ones. Using lubrication theory, Hosoi and Bush developed a one-dimensional model of the ridge instability which takes into account gravity, capillarity and Marangoni stresses at the surface of the film and results in a fourth-order non-linear partial differential equation describing the height of the ridges as a function of time and position along the plate. Two different but complementary numerical models were implemented to solve their equation. Both models are able to show development of ridges from random initial conditions as well as lateral ridge movement and coarsening. In addition to the numerical approaches some analysis was done on the equation to gain further insight into the nature of the ridge coarsening.
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Rock climbing sub-worlds: a segmentation studyRapelje, Brandon Wayne 15 November 2004 (has links)
Rock climbing participation is growing throughout the United States. Information on the participation patterns and preferences of groups of climbers can be used to help mangers make better informed decisions, allowing them to cater to the specific interests of climbing participants, ensure participant satisfaction and encourage continued patronage. This study explores variation in participant characteristics across segments of the climbing population. Because an individual's level of specialization will align him with other like-minded participants, an understanding of a participant's stages of involvement and level of specialization assists in understanding the social world's views and behaviors toward the resource and toward other participants. Information on participants' level of experience, level of commitment, and demographic dimensions can be used to better understand and manage climbers. This study aimed to identify differences among groups of climbers. The study measured across 484 participants. The participants were described by various dependent variables, which included demographic factors, level of specialization, motivations for climbing, types of conflicts and constraints experiences, and setting preferences. Measuring the climbers' participation patterns identified participant sub-world groups. The four groups of climbing participants, as identified by this study, were: infrequent climbers, frequent outdoor climbers, frequent indoor climbers, and avid climbers. While demographics are not significantly descriptive of climbing sub-world affiliations, this study found that there were differences among sub-world affiliates in terms of specialization level, motives, conflicts, constraints, and setting preferences.
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Rock climbing sub-worlds: a segmentation studyRapelje, Brandon Wayne 15 November 2004 (has links)
Rock climbing participation is growing throughout the United States. Information on the participation patterns and preferences of groups of climbers can be used to help mangers make better informed decisions, allowing them to cater to the specific interests of climbing participants, ensure participant satisfaction and encourage continued patronage. This study explores variation in participant characteristics across segments of the climbing population. Because an individual's level of specialization will align him with other like-minded participants, an understanding of a participant's stages of involvement and level of specialization assists in understanding the social world's views and behaviors toward the resource and toward other participants. Information on participants' level of experience, level of commitment, and demographic dimensions can be used to better understand and manage climbers. This study aimed to identify differences among groups of climbers. The study measured across 484 participants. The participants were described by various dependent variables, which included demographic factors, level of specialization, motivations for climbing, types of conflicts and constraints experiences, and setting preferences. Measuring the climbers' participation patterns identified participant sub-world groups. The four groups of climbing participants, as identified by this study, were: infrequent climbers, frequent outdoor climbers, frequent indoor climbers, and avid climbers. While demographics are not significantly descriptive of climbing sub-world affiliations, this study found that there were differences among sub-world affiliates in terms of specialization level, motives, conflicts, constraints, and setting preferences.
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An Ascent of PopocatepetlDouglass, A.E. 09 June 1897 (has links)
A description of a mountain climbing expedition. Manuscript states it was read June 9, 1897.
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GEOSPATIAL APPROACH TO PREDICTING CLIMBER IMPACTS AS A FUNCTION OF CLIMB CHARACTERISTICS (CHANGING USE, SITE CHARACTERISTICS, AND USER CHARACTERISTICS).Lane, Ely Thomas 01 August 2016 (has links)
Rock climbing is undergoing unexpectedly rapid growth across the United States and around the world. Industry estimations in the late 1990’s put the number of recreational rock climbers in the United States in the 400,000 range. In 2013, estimates placed the rock climbing population as larger than eleven million active climbers, an apparent expansion of two orders of magnitude in about twenty years. As the number of rock climbers utilizing protected areas to further their recreation goals increases, so goes the associated impacts those recreationists can have on the resources. From what is known about recreation impacts to soil and vegetative cover, these impacts grow non-linearly with the amount of use, but asymptotically compared to the number of users. In an era of difficult resource management budgeting and staffing, this use-impact dynamic can grow unchecked. Therefore, this thesis seeks to map existing climbs in a developed climbing area and combine those spatial data with user attribute data towards generating a predictive suitability map for climbs. As climbing grows in popularity, land managers and climbing advocacy organizations both stand to benefit from clearer understanding of the processes driving climb site location selection and ultimately the characteristics observed about the climbing routes created. Resource management is comparatively slow and hemmed in by regulation and planning requirements. What makes a particular area suitable for rock climbing route development is the end result of an extended career as a technical rock climber. A skilled rock climber would be able to explain why a particular site might be better or less suited for climbing development. However most land managers are not experienced rock climbers, requiring the investigation for indicators that would be discernable by a novice. Therefore, the need to link managers and activity participants is great, considering this knowledge gap we ask the question: “To what extent can onsite and user-defined climb characteristics be used to model location and extent of climbing routes’ development by climbers?” Distances (2-dimensional centroid-to-centroid) between climb sites’ areas of impact, associated approach trail, and ingress/egress points of the canyon area were computed to subsequently determine correlative relationships between number of bolts, as well as horizontal 2-dimensional linear distance between adjacent climbs. Non-spatial attributes of each climb were also assessed for correlations with the above spatial characteristics of each climb. There were statistical correlations found between the difference in climb quality ratings and the distance to nearest climbs as well as correlations between clustering of climbs and their quality rating. This combined with a willingness to travel the farthest distance possible in the area to reach high quality climbs has many resource management implications both for land managers and users.
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Regeneration ecology of the bamboo climber Flagellaria guineensis in the Transkei Coastal Forests, Eastern Cape, South AfricaTshaduli, Ndivhuwo January 2017 (has links)
Economic benefits obtained from Flagellaria guineensis, a climbing bamboo, by local people
received attention in previous studies but little is known about its regeneration ecology in three
different forest stand conditions, i.e. forest edges, forest gaps and mature closed-canopy stands.
In the Eastern Cape of South Africa the species grows in the Transkei Coastal Forests. The main
aim of this study was to assess the regeneration ecology of F. guineensis in those forests. The
specific objectives were to describe the phenological state that would influence the flowering,
fruiting and growth of the species, and to compare the culm (stem) development from the
rhizome between the different forest stand conditions. Phenological comparison was done in
forest edge and forest interior conditions two forests. Rating scales were applied to determine the
phenological states of the presence and amount of flower buds, open flowers, fruits, shoots and
seedlings. Development of F. guineensis was assessed by sampling clusters in the three different
forest stand conditions in three forests.
The observation made in two Transkei Coastal Forests indicate that F. guineensis regenerates by
producing seed, new vegetative shoots from rootstocks and also shoots at the growing tips. The
flowering and fruiting period occurred only in the rainy season in Mtambalala forest but both
rainy and dry seasons in Bulolo forest. More flowers and fruits of F. guineensis were found in
Bulolo forest and in the forest edge (where F. guineensis is able to form tangles on the canopy of
its host tree) respectively. This climbing bamboo clings on any plant around it for support and
forms tangles on the canopy of its host in forest edges with no direct damage caused to host
trees. The production of seedlings, shoots from the rhizome and shoots at the growing tips was constant during the study period in both study sites. The growth pattern of F. guineensis was
different when comparing the three Transkei Coastal Forests studied. Manubi forest was found to
have clusters and culms with the highest diameters and length compared to Mtambalala and
Mnenga forests. There was a significant difference in culm diameter and length of F. guineensis
between all three forests, whereas cluster diameter and number of culms per cluster were not
influenced by forest stand conditions. F. guineensis clusters were common in the forest edges or
gaps, and formed tangles in the canopy of their host trees. The described pattern of growth of F.
guineensis contributes to recovery of the forest edges or gaps by restricting easy movement in
and out of the forests. Several recommendations were made for harvesting of culms for basketmaking,
such as: it should be done with care to reduce tangles in the forest and tree canopies; it
must take place during the dry season, when the culms in a cluster are not flowering or fruiting;
and studies are needed on the growth rate of seedlings and their growth into the forest canopy
and how the bamboo can be cultivated outside the forest for better production of culms. / Dissertation (MSc)--University of Pretoria, 2017. / SAFCOL / Microbiology and Plant Pathology / MSc / Unrestricted
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Utilizing Acceptance and Commitment Therapy to Improve Rock Climbing Performance with Recreational ClimbersWesselhoff, Alexa 01 May 2020 (has links)
Rock climbing has been growing increasingly popular in the United States and around the world. Rock climbers frequently climb in the presence of fear and anxiety. Often climbers make mistakes while climbing that increase the potential for accidents and injuries. One area in which behavioral interventions have targeted sports performance is through the use of acceptance and commit training methods. Research has suggested that components of ACT may improve athletic performance such as present moment awareness, values clarification, and acceptance of challenging thoughts while performing. Studies have looked at the effects of training athletes within various sports such as basketball, powerlifting, swimming and golfing. Common skills that have been targeted include flow, attention to task, and goals/values identification. At this time, there has not been any research examining the impact of ACT on rock climbing performance. The current study examined the effects of ACT on rock climbing performance in two participants who frequently engaged in recreational rock climbing in a multiple baseline design across participants. Participants received ACT lessons prior to climbing and were assessed on falls and errors, speed, and heart rate. Results for both participants demonstrated improvements in decreasing falls and errors and increasing speed. There was no effect seen on heart rate. A second component of feedback on errors was added for participant one to further reduce errors.
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Design of a Biologically-Inspired Climbing Hexapod Robot for Complex ManeuversDiller, Eric David 09 January 2010 (has links)
No description available.
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Design Space and Motion Development for a Pole Climbing Serpentine Robot Featuring Actuated Universal JointsGoldman, Gabriel Jacob 09 September 2009 (has links)
Each year, falls from elevated structures, like scaffolding, kill or seriously injure over a thousand construction workers (Bureau of Labor Statistics, 2007). To prevent such falls, the development of a robotic system is proposed that can climb and navigate on the complex structures, performing hazardous inspection and maintenance in place of humans. In this work, a serpentine robotic system is developed that will be able to climb pole-like structures, such as scaffolding and trusses, commonly found on work sites. Serpentine robots have been proven to be effective at traversing unstructured terrains and manipulating complex objects. The work presented in this thesis adds a new method of mobility for serpentine robots, specifically those with actuated universal joint structures. Movement is produced by inducing a wobbling motion between adjacent modules through oscillatory motions in the actuated axis of the universal joint. Through the frictional interactions between the modules of the serpentine and the surface of the pole, the wobbling motion lets the serpentine effectively roll up the pole's surface.
This work investigates theoretical and experimental results for a serpentine robot climbing a pole structure. It discusses the structure and design parameters of the robot and develops relationships between them. These geometric and performance-based relationships are then used to create a design space that provides a guide for choosing a combination of module dimensions for a desired set of performance parameters. From this, case studies are shown which give examples of how the design space can be used for several different applications.
Based on the design space procedure, a serpentine robot, HyDRAS (Hyper-Redundant Discrete Robotic Articulated Serpentine) was designed and built. The robot was used to prove the validity of the design space procedure and to validate the climbing motion algorithms. Several tests were performed with HyDRAS that showed the practicality of the helical rolling motion, as well as the feasibility of serpentine pole climbing. Observations and discussion based on the experiments are given, along with the plans for future work involving pole-climbing serpentine robots. / Master of Science
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Rozdíly ve výživě české reprezentace ve sportovním lezení a výkonnostních lezců / Differences in nutrition of Czech national team in sport climbing and competitive climbersKuncířová, Veronika January 2019 (has links)
This master thesis evaluates the nutrition of Czech representation in sport climbing. The main goal is the monitoring of quantitative and qualitative composition of the Czech national team in sport climbing and comparing the results with the average group of climbers. The thesis is divided into two parts. The theoretical part deals with the morphological and functional characteristics of a sports climber. It also discusses the specific nutritional requirements related to this sport. The practical part consists of evaluation of the data, which were obtained on the basis of anthropometric measurement, short questionnaire, and five-day dietary record. Anthropometric measurements compare the body compositions of respondents. The aim of questionnaires is to evaluate the interest of individuals in nutrition and type of climbing training. Dietary records monitor the energy balance and the nutritional composition of the food. Eating records were evaluated in Nutri Pro Expert software. Results from both groups were compared with each other and also with the recommendations for the population. The purpose was to find out whether the nutrition recommendations of the Czech representation were fulfilled and also to describe the main differences in diet between top athletes and the average climbing group. The...
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