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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Predictive policing in an endangered species context : combating rhino poaching in the Kruger National Park

Koen, Hildegarde Suzanne January 2017 (has links)
Approximately three rhinos are poached daily in South Africa. Rhino poaching is a serious problem that a ects not only the rhino population of South Africa, but also the rhino population of the world. South Africa has the largest rhino population and of those rhinos the largest number can be found in the Kruger National Park (KNP). The KNP has been hit the hardest by the poaching epidemic, losing 1,175 rhinos in 2015 alone. Two big challenges are the size of the park and the unknown locations of both the poachers and new poaching events. The KNP is the size of a small country and there are simply not enough rangers to patrol this area e ectively. A costly solution would be to employ more rangers, but a proposed alternative is to reduce the search space and thus ensure that the rangers are allocated to the high risk areas first. A mathematical model was developed in the form of a Bayesian network (BN) to infer the most important factors contributing to poaching events and to model the rhino poaching problem. This model can be used to predict the area in which a future poaching attack could take place and thereby reduce the search area of rangers. The model also serves as a vehicle to enhance the understanding of the problem and encourage reasoning and discussion amongst decision makers. The map of the KNP is divided into cells and each cell is given a poaching probability, based on the outcome of the BN. This probability map forms a heat map that can be shown to the control centre and rangers can then be sent to the respective hotspots on the map. This is a proactive approach, which is in stark contrast to the numerous reactive approaches attempted thus far. This is the first BN modelling approach to the rhino poaching problem, and it is also the first BN application to wildlife crime. Previous applications of BN have only gone so far as environmental modelling, but not wildlife crimes. In this study the rhino poaching problem was shifted from a complex, ill-structured space to a position where researchers can begin to address the underlying problems by using a causal model as the vehicle for understanding the complex interplay between the factors a ecting poaching events. / Ongeveer drie renosters word daagliks in Suid-Afrika gestroop. Renosterstroping is 'n ernstige probleem wat nie net die renosterbevolking van Suid-Afrika raak nie, maar ook die res van die wêreld. Suid-Afrika het die grootste renoster bevolking in die wêreld, en die grootste getal van dié renosters word in die Kruger Nasionale Park (KNP) aangetref. Die KNP word die ergste geraak deur die stropings epidemie en 1,175 renosters is in 2015 gestroop. Twee groot uitdagings is die grootte van die park, asook die onbekende posisies van beide die stropers en die nuwe stropingsaanvalle. Die KNP is die grootte van 'n klein land en daar is eenvoudig nie genoeg veldwagters om hierdie area e ektief te patrolleer nie. 'n Duur oplossing sou wees om meer veldwagters aan te stel, maar 'n alternatief is om die soekarea van die veldwagters te verklein en sodoende te verseker dat die veldwagters die hoë-risiko areas eerste, en meer gereeld, patrolleer. 'n Wiskundige model in die vorm van 'n Bayesiese netwerk (BN) is ontwikkel om die belangrikste faktore te bepaal wat bydra tot stropingsaanvalle en uiteindelik die probleem te modelleer. Hierdie model kan gebruik word om die area te voorspel waar 'n stropingsaanval moontlik kan plaasvind en die soekarea van die veldwagters te verminder. Dit dien ook as 'n kanaal om die begrip van die probleem te verbeter en redenasie en bespreking onder besluitnemers aan te moedig. Die kaart van die KNP word in selle verdeel en aan elke sel word 'n stropingswaarskynlikheid toegeken gebaseer op die uitkoms van die BN. Hierdie waarskynlikheidskaart vorm 'n "hittekaart" wat aan die kontrolesentrum gewys kan word, en veldwagters kan dan na die onderskeie responskolle op die kaart gestuur word. Hierdie pro-aktiewe benadering is in teenstelling met huidige reaktiewe benaderings. Hierdie is die eerste BN modellering benadering tot die renosterstropingsprobleem, en dit is ook die eerste BN toepassing tot natuurlewe-misdaad. Vorige toepassings van BNs het omgewingsmodellering aangespreek, maar nie natuurlewe-misdade nie. In hierdie studie word aangetoon hoe die renosterstropings probleem geskuif is vanaf 'n komplekse, swak gestruktureerde probleemruimte na 'n omgewing waar navorsers kan begin om die onderliggende probleme aan te spreek deur gebruik te maak van 'n kausale model as die voertuig van begrip om die komplekse wisselwerking tussen faktore wat 'n stropingsaanval beïnvloed, te verstaan. / Thesis (PhD)--University of Pretoria, 2017. / Electrical, Electronic and Computer Engineering / PhD / Unrestricted
2

Modeling population dynamics of rhino-poacher interaction across South Africa and the Kruger National Park using ordinary differential equations

Makic, Vladimir 04 February 2021 (has links)
In this thesis, a system of ordinary differential equations (ODES) is presented to model the population dynamics between poachers and rhino as a predator-prey system in both South Africa (SA) and the Kruger National Park (KNP). The data used in this thesis consists mainly of government and police reports, as well publications from several NGOs and the limitations caused by this lack of applicable data are explored. The system dynamics are based on Lotka-Volterra differential equations, which are extended to include both a carrying capacity and the Allee effect. This thesis parameterises a model of the dynamics of the interaction between rhino and poachers for some time t and makes predictions based on the interpolation of the available data. The unknown rates and parameters relating to the behaviour of populations R and P are optimised by initially using a combination of educated guesses made from the available data or trial and error until set values are obtained. The remaining unknowns are numerically optimised based on the fixed value parameters. This is considered a constrained system, and the results obtained can only be viewed as constrained predictions based on parameter values obtained by a combination of trial and error and numerical optimisation; namely root mean square (RMS) error considering the available data and model solution at time t. Those parameter values obtained through RMS are regarded as error-minimising parameters within the scope of this research, and make up the final models which are referred to as the models which have been fitted to data. This thesis is an introductory, exploratory work into future attempts at modeling population dynamics with very little or no available data. The models are solved for in a constrained system, limiting the resulting predictions to constrained estimates based on the assigned values to unknown parameters. These solutions predict rhino stabilisation for both models, with active poachers dying out in the KNP but general co-existence observed across SA, within the constrained system.
3

An analysis of enforcement of laws on rhino poaching in South Africa

Mogoshi, Malesela Samuel January 2016 (has links)
Thesis (LLM.) -- University of Limpopo, 2016 / Rhinoceros (Rhinos) are poached at an alarming high rate in South Africa. The 1973 Convention on International Trade in Endangered Species of wild Fauna and Flora (CITES), prohibited the trade of rhino horns amongst its member states. Even though there are existing pieces of legislation in South Africa to curb the killing and illegal trade of rhino horns, compliance authorities rarely impose stringent sentences on culprits caught poaching rhinos. There should be stringent enforcement of laws on poachers and if caught, perpetrators should be brought to justice in order to deter aspiring or ambitious would-be perpetrators. Amendment of legislation currently used in South Africa on rhino poaching cases, if applied vigorously, would be more developmental in curbing the scourge. The syndicate are highly skilled and well equipped for the execution of illicit poaching. It is in few instances that perpetrators are arrested and prosecuted. Even if arrested and prosecuted, lenient sentences are imposed upon conviction. The most noticeable lacuna in South African Criminal Justice System, is the lack of capacity and skills in investigations and successful prosecutions of rhino poachers. Worst still, despite frequent media reports on the alarming rate of rhino poaching cases, few arrests and convictions are reported. This mini dissertation looks at rhino poaching as an organised crime, and focuses on literature review, legal framework and regulations, as well as comparative study on legislation which can be used to prosecute the perpetrators of this organised crime. The discourse recommends amendment of legislation presently used to prosecute rhino poaching offenders, and advocates that they should be stringently applied in order to curb the scourge.
4

The illegal trade in endangered animals in KwaZulu-Natal, with an emphasis on rhino poaching

Griffiths, Megan Laura 02 1900 (has links)
The illegal trade in endangered animals in KwaZulu-Natal, with an emphasis on rhino poaching, is tactically addressed in this dissertation. The aim is to expose the nature and extent of these crimes; the victims, offenders and modus operandi involved; the adjudication of wildlife offences; the causes and consequences concerned; the relevant criminological theories to explain these crimes; and recommendations for prevention. This research intends to examine the contemporary pandemic of rhino poaching in KwaZulu-Natal, South Africa, and offer potential techniques for intervention. Furthermore, one of the main goals of the study is to reveal and enhance the extremely neglected field of conservation criminology. A general disregard by society for the environment, as well as the overall ineffectiveness and corruption of criminal justice and conservation authorities, comes to the fore. The purpose of the research is therefore to suggest possible prevention strategies in order to protect the rights of endangered species. / Criminology and Security Science / M.A. (Criminology)
5

The illegal trade in endangered animals in KwaZulu-Natal, with an emphasis on rhino poaching

Griffiths, Megan Laura 02 1900 (has links)
The illegal trade in endangered animals in KwaZulu-Natal, with an emphasis on rhino poaching, is tactically addressed in this dissertation. The aim is to expose the nature and extent of these crimes; the victims, offenders and modus operandi involved; the adjudication of wildlife offences; the causes and consequences concerned; the relevant criminological theories to explain these crimes; and recommendations for prevention. This research intends to examine the contemporary pandemic of rhino poaching in KwaZulu-Natal, South Africa, and offer potential techniques for intervention. Furthermore, one of the main goals of the study is to reveal and enhance the extremely neglected field of conservation criminology. A general disregard by society for the environment, as well as the overall ineffectiveness and corruption of criminal justice and conservation authorities, comes to the fore. The purpose of the research is therefore to suggest possible prevention strategies in order to protect the rights of endangered species. / Criminology and Security Science / M.A. (Criminology)

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