20,877 research outputs found
A Mixed-Method Approach for Quantifying Illegal Fishing and Its Impact on an Endangered Fish Species
No full textIllegal harvest is recognized as a widespread problem in natural resource management. The use of multiple methods for quantifying illegal harvest has been widely recommended yet infrequently applied. We used a mixed-method approach to evaluate the extent, charac- ter, and motivations of illegal gillnet fishing in Lake Hovsgol National Park, Mongolia and its impact on the lake’s fish populations, especially that of the endangered endemic Hovsgol grayling (Thymallus nigrescens). Surveys for derelict fishing gear indicate that gillnet fishing is widespread and increasing and that fishers generally use 3–4 cm mesh gillnet. Interviews with resident herders and park rangers suggest that many residents fish for subsistence during the spring grayling spawning migration and that some residents fish commercially year-round. Interviewed herders and rangers generally agree that fish population sizes are decreasing but are divided on the causes and solutions. Biological monitoring indicates that the gillnet mesh sizes used by fishers efficiently target Hovsgol grayling. Of the five species sampled in the monitoring program, only burbot (Lota lota) showed a significant decrease in population abundance from 2009–2013. However, grayling, burbot, and roach (Rutilus ruti- lus) all showed significant declines in average body size, suggesting a negative fishing impact. Data-poor stock assessment methods suggest that the fishing effort equivalent to each resident family fishing 50-m of gillnet 11–15 nights per year would be sufficient to over- exploit the grayling population. Results from the derelict fishing gear survey and interviews suggest that this level of effort is not implausible. Overall, we demonstrate the ability for a mixed-method approach to effectively describe an illegal fishery and suggest that these methods be used to assess illegal fishing and its impacts in other protected areas.Peer reviewe
Implicit Learning of Recursive Context-Free Grammars
No full textContext-free grammars are fundamental for the description of linguistic syntax. However, most artificial grammar learning experiments have explored learning of simpler finite-state grammars, while studies exploring context-free grammars have not assessed awareness and implicitness. This paper explores the implicit learning of context-free grammars employing features of hierarchical organization, recursive embedding and long-distance dependencies. The grammars also featured the distinction between left-and right-branching structures, as well as between centre-and tail-embedding, both distinctions found in natural languages. People acquired unconscious knowledge of relations between grammatical classes even for dependencies over long distances, in ways that went beyond learning simpler relations (e.g. n-grams) between individual words. The structural distinctions drawn from linguistics also proved important as performance was greater for tail-embedding than centre-embedding structures. The results suggest the plausibility of implicit learning of complex context-free structures, which model some features of natural languages. They support the relevance of artificial grammar learning for probing mechanisms of language learning and challenge existing theories and computational models of implicit learning
Development of a reconfigurable assembly system with an integrated information management system
No full textThesis (M. Tech. (Engineering Electrical)) -- Central University of Technology, Free State, [2014]This dissertation evaluates the software and hardware components used to develop a
Reconfigurable Assembly System with an Integrated Information Management System. The assembly system consists of a modular Cartesian robot and vision system. The research focuses on the reconfigurability, modularity, scalability and flexibility that can be achieved in terms of the software and hardware components used within the system.
The assembly system can be divided into high-level control and low-level control
components. All information related to the product, Cartesian positioning and processes to
follow resides in the Information Management System. The Information Management
System is the high-level component and consists of a database, web services and low-levelcontrol drivers. The high-level system responds to the data received from the low-level systems and determines the next process to take place. The low-level systems consist of the PLC (Programmable Logic Controller) and the vision system. The PLC controls the Cartesian robot’s motor controllers and handles all events raised by field devices (e g. sensors or push buttons). The vision system contains a number of pre-loaded inspections used to identify barcodes and parts, obtain positioning data and verify the products’ build quality. The Cartesian robot’s positioning data and the vision system’s inspections are controlled by the Information Management System. The results showed that the high-level control software components are able to add more modularity and reconfigurability to the system, as it can easily adapt to changes in the product. The high-level control components also have the ability to be reconfigured while the assembly system is online without affecting the assembly system. The low-level control system is better suited to handling the control of motor controllers, field devices and vision inspections over an industrial network
Spontaneous music : the first generation British free improvisers
No full textThe British free improvisation scene originated in London and Sheffield during the
mid 1960s. In groups such as AMM, the Spontaneous Music Ensemble and Joseph
Holbrooke, a distinctive and ambitious musicality developed that still occupies most
of its protagonists forty years later.
Marked stylistic contrasts developed within the genre, notably the `atomistic' and
`laminar' methods of interaction. Nonetheless, a consistency of principle and practice
was also apparent that defined British free improvisation as unique. In some respects
the genre resembled its German, Dutch and American counterparts, and also the jazz
and classical avant-gardes that had inspired them. Both conceptually and practically,
however, clear differences remained.
The British free improvisers refined a method and an aesthetic of musical creativity,
which suggested an intimate perspective and a detailed analysis of that which we
accept as `music'. Its techniques and results were unconventional, but remained
consistent with music's defining concepts and experiences. As such, British free
improvisation suggested a more inclusive model of musicality than is common, and
implied a broad critique of the cultural values that define `music' at all. Though the
free improvisers themselves did not explicitly state the connection, their work may be
viewed in the context of Deconstruction: the post-structuralist analytical strategy
associated with philosopher Jacques Derrida.
British free improvisation culminated from innovations within the twentieth century
avant-garde. Referencing styles such as atonality and free jazz, it challenged the
aesthetic, technical and hierarchical standards of Western tradition in a form that was
striking and extreme, but also of logical development and focus. Free improvisation
owed explicit debt to a variety of other musics; its most singular achievement
however, was the redefinition of `rhythm' by which it disguised this fact.
The music of the first generation British free improvisers is reliant upon precise
conceptual and practical execution. But though this has enabled the genre to be
musically innovative, in the long term it has also become a logical problem. With
British free improvisation as its subject, the scrutiny of Deconstruction reveals
significant discrepancies between what `free improvisation' implies and what it
actually represents
Reynolds number effect on 3D turbulent offset jet reattaching to a free surface
No full textExperimental study was carried out to investigate the effect of Reynolds number on 3D offset jet reattaching to above free surface. Sharp edged square nozzle was used to produce the jets, and the measurements were performed at the following six different Reynolds numbers: 2300, 3700, 5100, 7900, 10300 and 11900. Detailed velocity measurements were made in the symmetry plane. From the PIV data, the mean velocity and turbulence statistics were obtained to study the effects of Reynolds number on the salient features of the jet flow. Preliminary results on streamwise mean velocity decay along the nozzle centerline, contours of streamwise mean velocity and Reynolds shear stress are presented herein
Travel photography
No full textThesiswithout Travel Photography it would be impossible to have an
idea of how our ancestors lived, worked and what exotic places
they visited. Travel photography can therefore indirectly
keep us in touch with our past.
In modern society, travel photography is becoming much more
popular because many photographers, amateur or professional
take images of places that are visited.
This dissertation will cover many aspects of travel
photography, discussing some of the earlier photographers, as
well as technical and praotioal aspects.
with travel photography, high ideals can be set. This is the
reason why the author has ohosen this topio to discuss. A
travel photographer must produoe images that would encourage
the viewers to visit these destinations
Open access self-archiving: An author study
No full textThis, our second author international, cross-disciplinary study on open access had 1296 respondents. Its focus was on self-archiving. Almost half (49%) of the respondent population have self-archived at least one article during the last three years. Use of institutional repositories for this purpose has doubled and usage has increased by almost 60% for subject-based repositories. Self-archiving activity is greatest amongst those who publish the largest number of papers. There is still a substantial proportion of authors unaware of the possibility of providing open access to their work by self-archiving. Of the authors who have not yet self-archived any articles, 71% remain unaware of the option. With 49% of the author population having self-archived in some way, this means that 36% of the total author population (71% of the remaining 51%), has not yet been appraised of this way of providing open access. Authors have frequently expressed reluctance to self-archive because of the perceived time required and possible technical difficulties in carrying out this activity, yet findings here show that only 20% of authors found some degree of difficulty with the first act of depositing an article in a repository, and that this dropped to 9% for subsequent deposits. Another author worry is about infringing agreed copyright agreements with publishers, yet only 10% of authors currently know of the SHERPA/RoMEO list of publisher permissions policies with respect to self-archiving, where clear guidance as to what a publisher permits is provided. Where it is not known if permission is required, however, authors are not seeking it and are self-archiving without it. Communicating their results to peers remains the primary reason for scholars publishing their work; in other words,
researchers publish to have an impact on their field. The vast majority of authors (81%) would willingly comply with a mandate from their employer or research funder to deposit copies of their articles in an institutional or subject-based repository. A further 13% would comply reluctantly; 5% would not comply with such a mandate
Obstacles on the path: An exposition of the experience of car-free living
No full textThe contemporary focus by local and central government on the promotion of sustainable transport options has highlighted the need for commuting to move away from the current dependence on private cars to more public and active (walking and cycling) modes of transport. Given the prominence of the motor car in personal transport options however, choosing to live car-free in this car dependent culture appears at first glance to be an irrational choice. This research explores the lived experiences of a group of Hamilton residents who have made such a choice. Using a grounded theory approach, the thesis presents the results of interviews with nine car-free Hamilton residents who shared their personal transport stories, which include their childhood experiences, but focus on their current everyday practices and experiences. Through semi-structured interviews, the costs and benefits of a car-free lifestyle are articulated and analysed. Their motivations for choosing to forgo cars and their solutions for overcoming potential barriers to car-free living are also reported and explored. The collected data generated a range of themes which are presented in three chapters, each covering a specific aspect of the participants’ stories. The first group of themes relate to the public sphere, the second to the private realm and the final group emanates from specific elements of car-free living that the thesis sought to clarify through the participants’ stories. The key finding is that living car-free within Hamilton City is viewed by the participants as a well reasoned and eminently sensible choice, which produces multiple benefits. In addition to their reduced environmental footprints, the participants value the social interaction associated with active and public transport. Their consensus is that they are healthier, wealthier and more involved members of the community. The most problematic areas of living without a car were associated with recreational and social activities, which often do not coincide with public transport schedules or involve distances too great for active transport. The benefits far outweigh any disadvantages however, and ultimately, this thesis concludes that a motor car is not necessary for the everyday activities of urban living in Hamilton and any associated inconveniences are not as insurmountable as generally imagined
The giant sucking sound: did NAFTA devour the Mexican peso?
No full textFive years of economic reforms had made Mexico a model for other developing nations by the end of 1993, when Mexico was preparing to enter into the North American Free Trade Agreement (NAFTA) with Canada and the United States. But less than a year later, in December 1994, Mexico experienced a severe financial crisis, forcing it to borrow from the IMF and the United States. Some commentators blamed the enactment of NAFTA for the devaluation of the peso and the ensuing economic turmoil in Mexico, with some calling for renegotiation or even repeal of the agreement. Author Christopher J. Neely examines the relationship between NAFTA and the 1994 peso crisis and raises some provocative questions: did NAFTA cause or exacerbate the devaluation of the peso? or did NAFTA help alleviate some of the consequences of the crisis?North American Free Trade Agreement ; Mexico ; Capital movements ; Devaluation of currency ; Peso, Mexican
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