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University of Illinois – Urbana-Champaign
1.
Baharian Khoshkhou, Golshid.
Stochastic sequential assignment problem.
Degree: PhD, 0127, 2014, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/50503
► The stochastic sequential assignment problem (SSAP) studies the allocation of available distinct workers with deterministic values to sequentially-arriving tasks with stochastic parameters so as to…
(more)
▼ The stochastic sequential assignment problem (SSAP) studies the allocation of available distinct workers with deterministic values to sequentially-arriving tasks with stochastic parameters so as to maximize the expected total reward obtained from the assignments. The difficulty and challenge in making the assignment decisions is that the assignments are performed in real-time; specifically, pairing a worker with a task is done without knowledge of future task values. This thesis focuses on studying practical variations and extensions of the SSAP, with the goal of eliminating restricting assumptions so that the problem setting converges to that of real-world problems.
The existing SSAP literature considers a risk-neutral objective function, seeking an assignment policy to maximize the expected total reward; however, a risk-neutral objective function is not always desirable for the decision-maker since the probability distribution function (pdf) of the total reward might carry a high probability of low values. To take this issue into account, the first part of this dissertation studies the SSAP under a risk-sensitive objective function. Specifically, the assignments are performed so as to minimize the
threshold probability, which is the probability of the total reward failing to achieve a specified target (
threshold). A target-dependent Markov decision process (MDP) is solved, and sufficient conditions for the existence of a deterministic Markov optimal policy are provided. An approximate algorithm is presented, and convergence of the approximate value function to the optimal value function is established under mild conditions.
The second part of this thesis analyzes the limiting behavior of the SSAP as the number of assignments approaches infinity. The optimal assignment policy for the basic SSAP has a
threshold structure and involves computing a new set of breakpoints upon the arrival of each task, which is cumbersome for large-scale problems. To address this issue, the second part of this dissertation focuses on obtaining stationary (time-independent) optimal assignment policies that maximize the long-run expected reward per task and are much easier to perform in real-world problems. An exponential convergence rate is established for the convergence of the expected total reward per task to the optimal value as the number of tasks approaches infinity. The limiting behavior of the SSAP is studied in two different settings. The first setting assumes an independent and identically distributed (IID) sequence of arriving tasks with observable distribution functions, while the second problem considers the case where task distributions are unobservable and belong to a pool of feasible distributions.
The next part of this dissertation basically brings the first two parts together, studying the limiting behavior of the target-dependent SSAP, where the goal is finding an assignment policy that minimizes the probability of the long-run reward per task failing to achieve a given target value. It is proven that the…
Advisors/Committee Members: Jacobson, Sheldon H. (advisor), Chen, Xin (Committee Chair), Jacobson, Sheldon H. (committee member), Kiyavash, Negar (committee member), Shanbhag, Vinayak V. (committee member).
Subjects/Keywords: sequential assignment; Markov decision process; stationary policy; hidden Markov model; threshold criteria; risk measure
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APA (6th Edition):
Baharian Khoshkhou, G. (2014). Stochastic sequential assignment problem. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/50503
Chicago Manual of Style (16th Edition):
Baharian Khoshkhou, Golshid. “Stochastic sequential assignment problem.” 2014. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed December 12, 2019.
http://hdl.handle.net/2142/50503.
MLA Handbook (7th Edition):
Baharian Khoshkhou, Golshid. “Stochastic sequential assignment problem.” 2014. Web. 12 Dec 2019.
Vancouver:
Baharian Khoshkhou G. Stochastic sequential assignment problem. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2014. [cited 2019 Dec 12].
Available from: http://hdl.handle.net/2142/50503.
Council of Science Editors:
Baharian Khoshkhou G. Stochastic sequential assignment problem. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/50503

University of Cincinnati
2.
Masterson, Elizabeth A.
Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria.
Degree: PhD, Medicine: Epidemiology (Environmental
Health), 2012, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1328890418
► Background: Twenty-two million workers are exposed to hazardous noise in the United States. Occupational hearing loss can occur when workers are exposed to loud…
(more)
▼ Background: Twenty-two million workers are
exposed to hazardous noise in the United States. Occupational
hearing loss can occur when workers are exposed to loud noise or
ototoxic chemicals. The purpose of this study was to estimate the
prevalence of workers with National Institute for Occupational
Safety and Health (NIOSH) significant
threshold shifts (NSTS),
Occupational Safety and Health Administration (OSHA) standard
threshold shifts (OSTS), and OSTS with age correction (OSTS-A)
among U.S. industries, and to compare the prevalence across
regulation
criteria. Methods: 2000-2008
audiograms for male and female workers ages 18-65, who had higher
occupational noise exposures than the general population, were
examined. Prevalence and adjusted prevalence ratios (PRs) for NSTS,
OSTS and OSTS-A were estimated and compared across industries.
McNemar’s Test comparisons were also performed to compare the
estimated prevalence of NSTS to OSTS and NSTS to OSTS-A, for each
demographic and industry. P-values were generated for each
comparison. Results: 20% of workers had NSTS, 14%
had OSTS and 7% had OSTS-A. Industries with the highest prevalence
for NSTS, OSTS, and OSTS-A were Healthcare and Social Assistance
(26%, 17% and 8%), Primary Metal Manufacturing (25%, 16% and 8%),
Miscellaneous Manufacturing (25%, 18% and 9%), and Real Estate and
Rental and Leasing (24%, 18% and 10%).The prevalences of workers
with OSTS and OSTS-A were about 66-70% and 30-33% of the prevalence
of workers with NSTS, respectively. Conclusions:
After 40 years of progress in hearing conservation research and
technology, current regulations should be updated. OSTS likely
fails to identify a third of the workers who need intervention and
OSTS-A does not identify 65-75%. Workers in the industries
identified above need better engineering controls for noise and
stronger hearing conservation strategies. More research is needed
within "low-risk" industries to identify exposed workers and the
mechanisms involved, and more effective worker training practices
need to be developed.
Advisors/Committee Members: Rao, Marepalli (Committee Chair).
Subjects/Keywords: Occupational Safety; occupational hearing loss; occupational noise exposure regulation; hazardous noise; noise-induced hearing loss; standard threshold shift; hearing shift criteria
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Masterson, E. A. (2012). Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1328890418
Chicago Manual of Style (16th Edition):
Masterson, Elizabeth A. “Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria.” 2012. Doctoral Dissertation, University of Cincinnati. Accessed December 12, 2019.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1328890418.
MLA Handbook (7th Edition):
Masterson, Elizabeth A. “Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria.” 2012. Web. 12 Dec 2019.
Vancouver:
Masterson EA. Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria. [Internet] [Doctoral dissertation]. University of Cincinnati; 2012. [cited 2019 Dec 12].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1328890418.
Council of Science Editors:
Masterson EA. Prevalence of Workers with Shifts in Hearing by Industry: A
Comparison of Occupational Noise Exposure Regulation
Criteria. [Doctoral Dissertation]. University of Cincinnati; 2012. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1328890418

University of Washington
3.
Kennedy, Alec Ito.
Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education.
Degree: PhD, 2019, University of Washington
URL: http://hdl.handle.net/1773/44672
► In education, students are often assigned to specialized programs or receive targeted interventions based on some standards and requirements. The criteria used to select the…
(more)
▼ In education, students are often assigned to specialized programs or receive targeted interventions based on some standards and requirements. The
criteria used to select the students for such targeted policies must weigh the trade-off between serving too many students and not serving enough. Under such selection
criteria, I identify students who are selected into a treatment category that does not maximize their benefits as consequences of misassignment to treatment. As targeted policy interventions are aimed at providing supports for students with specific needs, it is important that we establish a firm understanding and provide guidance on how selection
criteria should be designed and used to assure that all students are appropriately served. This dissertation explores several aspects of such selection
criteria through the examination of three policies in education that seek to select students (or school districts) for targeted interventions and supports. The exploration provides learning and recommendations on how federal, state, and local governments can leverage data and analysis to limit the consequences of misassignment to treatment. The first chapter of this dissertation introduces a framework to facilitate in the understanding of the consequences to misassignment to treatment. The framework establishes a way of understanding how selection
criteria for targeted policy interventions can fail and lead to losses of benefits for both targeted and non-targeted groups. The second chapter, Are We Correctly Measuring the Disproportionality of Minority Students in Special Education?, asks whether the current methods for measuring disproportionality in special education are accurately identifying school districts in need of a change of referral practices. Currently, the U.S. Department of Education's Office of Civil Rights (OCR) monitors whether school districts disproportionately refer minority students into special education services in an effort to prevent overreferral. However, these monitoring methods do not account for student-level factors (notably, socioeconomic status) which have been theorized to be positively associated with the presence of a learning disability. If minority students are more likely to experience low socioeconomic status than their White peers, then there may be good reason for minority students to be overrepresented in special education (i.e., the current measures of disproportionality could be susceptible to bias). In this chapter, I introduce an alternative measure for tracking disproportionality that removes this threat of bias. I then compare the performance of this alternative measure of disproportionality with the one currently in use and find that the currently used measure tends to overstate disproportionality. This finding suggests that current measures used by states to monitor disproportionality may incorrectly label some school districts as having an overrepresentation problem when, in fact, they do not. The third chapter, Successfully Transitioning English Language Learners…
Advisors/Committee Members: Long, Mark C. (advisor).
Subjects/Keywords: English Learner reclassification; Selection criteria; Special Education disproportionality; Targeted policy interventions; Threshold setting in education; Education policy; Public policy; Public affairs
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kennedy, A. I. (2019). Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/44672
Chicago Manual of Style (16th Edition):
Kennedy, Alec Ito. “Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education.” 2019. Doctoral Dissertation, University of Washington. Accessed December 12, 2019.
http://hdl.handle.net/1773/44672.
MLA Handbook (7th Edition):
Kennedy, Alec Ito. “Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education.” 2019. Web. 12 Dec 2019.
Vancouver:
Kennedy AI. Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education. [Internet] [Doctoral dissertation]. University of Washington; 2019. [cited 2019 Dec 12].
Available from: http://hdl.handle.net/1773/44672.
Council of Science Editors:
Kennedy AI. Consequences of Misassignment to Treatment: Examining Targeted Policy Interventions in Education. [Doctoral Dissertation]. University of Washington; 2019. Available from: http://hdl.handle.net/1773/44672

University of Manitoba
4.
Tahir, Bushra.
From doctrine to practice: responsibility to protect and military intervention in Libya 2011.
Degree: Political Studies, 2016, University of Manitoba
URL: http://hdl.handle.net/1993/31161
► The intervention in Libya is the best example to date to judge the implementation of the Responsibility to Protect. In 2011, public demonstrations started in…
(more)
▼ The intervention in Libya is the best example to date to judge the implementation of the Responsibility to Protect. In 2011, public demonstrations started in Libya seeking political and economic reforms in the country. In return, the Libyan President Maummar Al-Qaddafi threatened mass atrocities in Libya. This allowed the UNSC to sanction the use of force against Qaddafi’s regime in order to protect civilians. First, under resolution 1970 (2011), the UNSC referred the case to the International Criminal Court and applied sanctions. Second, via resolution 1973 (2011), the application of force was approved for the express purpose of “protecting civilians.” This thesis assess whether the military intervention in Libya in 2011 was R2P case. This question is answered by an analysis based upon the UNSC’s Resolutions, Council’s proceedings, and other official documents.
Advisors/Committee Members: Fergusson, James (Political Studies) (supervisor), Charron, Andrea (Political Studies).
Subjects/Keywords: Responsibility to Protect; Libya; Maummar Al Qaddafi; UNSC Resolution 1970; UNSC Resolution 1973; NATO; Just Cause; Right Intention; Last Resort; Proportional Means; Threshold Criterion; Precautionary Criteria
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tahir, B. (2016). From doctrine to practice: responsibility to protect and military intervention in Libya 2011. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/31161
Chicago Manual of Style (16th Edition):
Tahir, Bushra. “From doctrine to practice: responsibility to protect and military intervention in Libya 2011.” 2016. Masters Thesis, University of Manitoba. Accessed December 12, 2019.
http://hdl.handle.net/1993/31161.
MLA Handbook (7th Edition):
Tahir, Bushra. “From doctrine to practice: responsibility to protect and military intervention in Libya 2011.” 2016. Web. 12 Dec 2019.
Vancouver:
Tahir B. From doctrine to practice: responsibility to protect and military intervention in Libya 2011. [Internet] [Masters thesis]. University of Manitoba; 2016. [cited 2019 Dec 12].
Available from: http://hdl.handle.net/1993/31161.
Council of Science Editors:
Tahir B. From doctrine to practice: responsibility to protect and military intervention in Libya 2011. [Masters Thesis]. University of Manitoba; 2016. Available from: http://hdl.handle.net/1993/31161

University of South Florida
5.
McCluskey, James.
Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans.
Degree: 2008, University of South Florida
URL: https://scholarcommons.usf.edu/etd/390
► Significant benzene exposure has historically been associated with the development of a host of hematological disorders in humans and animals. In particular, benzene is known…
(more)
▼ Significant benzene exposure has historically been associated with the development of a host of hematological disorders in humans and animals. In particular, benzene is known to cause disturbances of the peripheral blood, aplastic anemia and cancer of the lymphohematopoietic system. In 1928, the first modern report of an association between cancer and benzene exposure was published. This case report was followed by additional reports from around the world. In most instances, ailments resulted from long term, high level exposure to benzene found in glues, and through accidental industrial spills. Throughout the 1960's and 1970's, case reports accumulated linking benzene exposure to hematological cancers, particularly among leather workers in Turkey and Italy. At the time, only qualitative measures of benzene exposure were often available and most exposure information was based upon short term grab samples and subjective symptoms. However, this situation changed drastically in the mid-1970s, when the first report was published on a little known industry that manufactured rubber hydrochloride, also known as Pliofilm. This clear film product was made from natural rubber latex and processing utilized benzene in multiple stages. It appeared from the outset that there were an unusually large number of acute leukemia cases in this cohort of workers. Since that time, multiple follow-up evaluations of the same cohort have attempted to refine the benzene exposure of these workers. Benzene has subsequently been classified as a human carcinogen by several regulatory bodies and the allowable 8 hour time-weighted average has been lowered to 1 ppm. In pursuing the goal of protecting workers, regulatory bodies utilize a linear extrapolation, or no threshold dose, approach to cancer causation. This methodology assumes that every exposure brings an incremental rise in risk. In this work, the linear extrapolation methodology is tested utilizing the criteria proposed by Sir Bradford Hill. The Hill Criteria are used to critically evaluate the weight of evidence for a threshold dose that can cause hematological cancer in humans following benzene exposure. This evaluation revealed that there is sufficient evidence for a threshold dose and that linear extrapolation is designed to protect, not predict disease.
Subjects/Keywords: Threshold; Causation; Hill Criteria; Cancer; Lymphoproliferative; Leukemia; American Studies; Arts and Humanities
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McCluskey, J. (2008). Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/390
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
McCluskey, James. “Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans.” 2008. Thesis, University of South Florida. Accessed December 12, 2019.
https://scholarcommons.usf.edu/etd/390.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
McCluskey, James. “Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans.” 2008. Web. 12 Dec 2019.
Vancouver:
McCluskey J. Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans. [Internet] [Thesis]. University of South Florida; 2008. [cited 2019 Dec 12].
Available from: https://scholarcommons.usf.edu/etd/390.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
McCluskey J. Benzene Related Hematological Disorders: Evidence for a Threshold in Animals and Humans. [Thesis]. University of South Florida; 2008. Available from: https://scholarcommons.usf.edu/etd/390
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
6.
Wang, Yiyuan.
Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control.
Degree: PhD, Mathematics & Statistics, 2019, York University
URL: http://hdl.handle.net/10315/35921
► Mosquito-borne diseases (MBD), such as West Nile virus (WNV), dengue, and Zika virus, have become a significant global health burden for human society. Complex factors,…
(more)
▼ Mosquito-borne diseases (MBD), such as West Nile virus (WNV), dengue, and Zika virus, have become a significant global health burden for human society. Complex factors, including weather conditions, anthropogenic land use and vector-virus-host interactions, greatly affect the mosquito abundance and distribution, and the disease transmission process. In this dissertation, I will investigate the mosquito population dynamics and transmission dynamics of MBDs, and explore how these factors play roles in the MBDs. Particularly, we use WNV and Culex mosquitoes (WNV vectors) in the Region of Peel, Ontario, Canada, as an example for this study.
We first study single species population models for the mosquito and the bird respectively. For mosquitoes, we take into account the contribution of the mosquito feeding preference to the oviposition and the intraspecific competition among preadult mosquitoes. For birds, we summarize the impacts of bird species, migration and age states on the transmission of WNV and explore the influence of WNV on bird populations.
Then we establish a model to track the number of mosquitoes collected in a trap, predict mosquito trap counts and real adult mosquito population in an effective trapping zone. We consider the trapping mechanism of a CDC light trap and collecting procedure, and show how weather, mosquito and host selecting behaviors affect the trap counts.
To explore the transmission dynamics of WNV, we develop a single-season mosquito-bird model considering stormwater management ponds, temperature and precipitation. We reveal that moderate temperature and precipitation, weaker intraspecific competition will increase the mosquito population and consequently the potential for an outbreak. This work can be used to guide WNV programs in local health units where monitoring standing water and larviciding is often used to control mosquito populations and the spread of WNV.
To investigate backward bifurcation,
threshold dynamics and outbreak recurrence mechanisms, we propose improved mosquito-bird compartment models. We define a new risk index to characterize the potential risk of WNV infections. We also develop the risk assessment
criteria, which can be helpful to determine the risk level if there is an outbreak. Our evaluation results are generally consistent with results based on the minimum infection rate.
Advisors/Committee Members: Zhu, Huaiping (advisor).
Subjects/Keywords: Public health; Mosquito-borne diseases; West Nile virus; Transmission dynamic models; Single species population models; Temperature; Precipitation; CDC light traps; Feeding preferences; Backward bifurcation; Threshold dynamics; Stormwater management ponds; Risk assessment criteria; Vector abundance; Culex mosquito; Effective trapping zone; Trap counts; Intraspecific competition; Risk assessment
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, Y. (2019). Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control. (Doctoral Dissertation). York University. Retrieved from http://hdl.handle.net/10315/35921
Chicago Manual of Style (16th Edition):
Wang, Yiyuan. “Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control.” 2019. Doctoral Dissertation, York University. Accessed December 12, 2019.
http://hdl.handle.net/10315/35921.
MLA Handbook (7th Edition):
Wang, Yiyuan. “Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control.” 2019. Web. 12 Dec 2019.
Vancouver:
Wang Y. Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control. [Internet] [Doctoral dissertation]. York University; 2019. [cited 2019 Dec 12].
Available from: http://hdl.handle.net/10315/35921.
Council of Science Editors:
Wang Y. Transmission Dynamics of Mosquito-Borne Diseases: Modeling, Analysis, Prediction and Control. [Doctoral Dissertation]. York University; 2019. Available from: http://hdl.handle.net/10315/35921
7.
Sauvaget, Baptiste.
Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation.
Degree: Docteur es, Géosciences et géoingénierie, 2019, Paris Sciences et Lettres
URL: http://www.theses.fr/2019PSLEM014
► Les grands réaménagements urbains génèrent d’importants volumes de terres excavées, dont la valorisation est désormais possible si elles sont compatibles avec le fond pédo-géochimique du…
(more)
▼ Les grands réaménagements urbains génèrent d’importants volumes de terres excavées, dont la valorisation est désormais possible si elles sont compatibles avec le fond pédo-géochimique du site receveur. Afin de faciliter cette valorisation, cette thèse s’intéresse à des méthodologies de traitement de données acquises à d'autres fins que la détermination du fond pédo-géochimique, afin de fournir un référentiel de qualité géochimique des sols urbains à l'échelle d'un quartier ou d'une ville. Les premiers tests montrent les limites des calculs statistiques, usuellement utilisés avec des données dédiées au fond pédo-géochimique du fait de leur sensibilité à la limite de quantification, à la loi de distribution ou encore au pourcentage d'anomalie. Le découpage du territoire en entités géographiques cohérentes à partir de la nature des sols et sous-sols et des pressions anthropiques (actuelles ou passées) permet la constitution de différents niveaux de fond suivant la qualité géochimique des sols, mais une des difficultés concerne le renseignement de l'ensemble des entités. La classification statistique des échantillons, même spatialisée, n'apporte, actuellement pas de résultats exploitables pour la gestion des terres excavées. Enfin, le filtrage géostatistique via un modèle linéaire de corégionalisation présente une alternative solide pour le filtrage des anomalies et l'estimation du fond à l'échelle d'un quartier.
Large urban redevelopments generate large volumes of excavated soils whose reusability is now possible if they are compatible with the pedo-geochemical background of the receiving site. In order to facilitate this valorization, this thesis focuses on processing methodologies on data acquired for other purposes than the determination of the pedo-geochemical background, in order to provide a geochemical quality reference system for urban soils at the scale of one neighborhood or city. The first tests show the limits of the statistical stresholds, usually used with data dedicated to the pedo-geochemical background because of their sensitivity to the limit of quantification, to the distribution law or to the percentage of anomaly. The segmentation of the territory into coherent geographical entities based on the nature of the soil and subsoil and the anthropogenic pressures (current or past) allows the constitution of different geochemical background levels according to the geochemical quality of the soils, but one of the difficulties concerns the information of all entities. The statistical classification of the samples, even if spatialized, does not currently provide usable results for the management of the excavated earth. Lastly, geostatistical filtering via a linear model of coregionalisation provides a solid alternative for anomaly filtering and background estimation at a neighborhood scale.
Advisors/Committee Members: De fouquet, Chantal (thesis director), Le Guern, Cécile (thesis director).
Subjects/Keywords: Fond pédo-Géochimique; Sols urbains; Filtrage géostatistique; Découpage du territoire; Analyse multi-Critères; Classification; Seuil; Statistique; Pedo-Geochemical background; Urban soils; Geostatistical filtering; Territorial segmentation; Multi-Criteria analysis; Classification; Threshold; Statistics; 551.9
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sauvaget, B. (2019). Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation. (Doctoral Dissertation). Paris Sciences et Lettres. Retrieved from http://www.theses.fr/2019PSLEM014
Chicago Manual of Style (16th Edition):
Sauvaget, Baptiste. “Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation.” 2019. Doctoral Dissertation, Paris Sciences et Lettres. Accessed December 12, 2019.
http://www.theses.fr/2019PSLEM014.
MLA Handbook (7th Edition):
Sauvaget, Baptiste. “Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation.” 2019. Web. 12 Dec 2019.
Vancouver:
Sauvaget B. Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation. [Internet] [Doctoral dissertation]. Paris Sciences et Lettres; 2019. [cited 2019 Dec 12].
Available from: http://www.theses.fr/2019PSLEM014.
Council of Science Editors:
Sauvaget B. Constitution de référentiels géochimiques locaux pour les sols et proches sous-sols urbains : de la base de données à l'interprétation géostatistique : Constitution of local geochemical references for urban soils and subsoils : from database to geostatistical interpretation. [Doctoral Dissertation]. Paris Sciences et Lettres; 2019. Available from: http://www.theses.fr/2019PSLEM014

University of Waterloo
8.
Stechlinski, Peter.
A Study of Infectious Disease Models with Switching.
Degree: 2009, University of Waterloo
URL: http://hdl.handle.net/10012/4424
► Infectious disease models with switching are constructed and investigated in detail. Modelling infectious diseases as switched systems, which are systems that combine continuous dynamics with…
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▼ Infectious disease models with switching are constructed and investigated in detail. Modelling infectious diseases as switched systems, which are systems that combine continuous dynamics with discrete logic, allows for the use of methods from switched systems theory. These methods are used to analyze the stability and long-term behaviour of the proposed switched epidemiological models. Switching is first incorporated into epidemiological models by assuming the contact rate to be time-dependent and better approximated by a piecewise constant. Epidemiological models with switched incidence rates are also investigated. Threshold criteria are established that are sufficient for the eradication of the disease, and, hence, the stability of the disease-free solution. In the case of an endemic disease, some criteria are developed that establish the persistence of the disease. Lyapunov function techniques, as well as techniques for stability of impulsive or non-impulsive switched systems with both stable and unstable modes are used. These methods are first applied to switched epidemiological models which are intrinsically one-dimensional. Multi-dimensional disease models with switching are then investigated in detail. An important part of studying epidemiology is to construct control strategies in order to eradicate a disease, which would otherwise be persistent. Hence, the application of controls schemes to switched epidemiological models are investigated. Finally, epidemiological models with switched general nonlinear incidence rates are considered. Simulations are given throughout to illustrate our results, as well as to make some conjectures. Some conclusions are made and future directions are given.
Subjects/Keywords: epidemiology; infectious diseases; basic reproduction number; threshold criteria; time-dependent contact rate; incidence rate; disease-free solution; persistence; switched systems; hybrid systems
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APA (6th Edition):
Stechlinski, P. (2009). A Study of Infectious Disease Models with Switching. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/4424
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Stechlinski, Peter. “A Study of Infectious Disease Models with Switching.” 2009. Thesis, University of Waterloo. Accessed December 12, 2019.
http://hdl.handle.net/10012/4424.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Stechlinski, Peter. “A Study of Infectious Disease Models with Switching.” 2009. Web. 12 Dec 2019.
Vancouver:
Stechlinski P. A Study of Infectious Disease Models with Switching. [Internet] [Thesis]. University of Waterloo; 2009. [cited 2019 Dec 12].
Available from: http://hdl.handle.net/10012/4424.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Stechlinski P. A Study of Infectious Disease Models with Switching. [Thesis]. University of Waterloo; 2009. Available from: http://hdl.handle.net/10012/4424
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
.