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Les codes identifiants ont été introduits en 1998 par Karpovsky, Chakrabarty et Levitin. Un code identifiant est un sous-graphe tel que chaque sommet est identifié de manière unique par les sommets du code qui l'entourent. Il existe plusieurs variantes de ces codes, dont notamment une version colorée dans laquelle les sommets sont identifiés par les couleurs dans leur voisinage. Dans cette thèse, nous cherchons en particulier à construire un cycle le plus grand possible qui admette une coloration identifiante, étant donné un nombre de couleurs fixé. Nous avons aussi étudié le problème des codes identifiants sur une classe particulière de graphes orientés : les tournois. Dans une seconde partie, nous avons aussi étudié deux jeux particuliers. Le premier est une généralisation des jeux octaux - qui se jouent normalement sur un tas - aux graphes. Plus précisemment, le jeu 0.33 ; chaque joueur peut retirer un ou deux sommets voisins d'un graphe, sans déconnecter ce dernier. Le premier qui ne peut plus jouer perd. Nous avons été capable de caractériser les issues de ce jeu dans des classes de graphes particulières, les étoiles subdivisées et les bi-étoiles subdivisées. Le second jeu est appelé le jeu du Pompier (Firefighter). Il consiste à arrêter un feu qui se propage dans un graphe en protégeant des sommets à chaque tour. Nous avons résolu une conjecture sur ce jeu, et introduit la version online, pour laquelle nous avons pu donner des résultats d'approximation. / Identifying codes were introduced in 1998 by Karpovsky, Chakrabarty and Levitin. An identifying code is a subgraph such that each vertex is uniquely identified by the vertices in its neighborhood. There are several variants of these codes, including a colored version where the vertices are identified by the colors in their neighborhood. In this phd, we want to build an identifying coloring of a large cycle, given a fixed number of colors. We also studied identified codes in a certain class of oriented graphs: tournaments. We have also studied some topics in the game theory. The first one is a generalization of octal games, where we play on a graph instead of a heap. More precisely, the 0.33 game; each player can remove one or two vertices in a graph, with no disconnection allowed. The first player who cannot play loses. We studied this game in some graph classes: subdivided stars and subdivided bistars. The other game is called the Firefighter game. It's a one player game, where this one wants to contain a spreading fire in a graph. We solved a conjecture about this game, and introduced the online version of the game, for which we found some approximation results.

An oft overlooked population in research, firefighters of volunteer and paid-on-call fire departments respond to nighttime calls as a supplement to their normal working hours, making the duties taxing on the autonomic system leading to cardiovascular and endocrine disruptions. These duties also come with a tax burden on the volume and distribution of sleep. The current study was executed in order to gain valuable insight into the impact of nighttime call response in this population and the magnitude and duration of any perturbations. Eight firefighters from Greater Victoria Volunteer and Paid-on-call departments were recruited to wear Equivital EQ02 heart monitors and FitBit Charge 2 devices to record autonomic cardiovascular responses and track sleep between 1900 and 0700. HR MAX was found to significantly increase with a large effect size (p<0.0005) from 97 +/- 20 to 157 +/- 18 beats per minute in the 15 minutes preceding versus following a call within the time period. LF/HF ratios increased during the first 15-minutes following a call to 4.055 +/- 1.316 from 1.911 +/- 0.599 pre-call. HF power, RMSSD, and pNN50 all decreased significantly compared to pre-call values (796.176 +/- 414.296 ms2 vs 244.119 +/- 153.880 ms2, 51.940 +/- 7.119 ms vs 35.072 +/- 2.624 ms, 25.017 +/- 7.034% vs 7.403 +/- 2.411%). Further, all HRV measures with the exception of normalized LF and HF were found to be significantly different when waking for and attending a call versus waking on a normal day despite there being no significant differences among any variables when going to bed on nights with and without a call. Total and REM sleep were the most significantly impacted measurables of sleep. Total sleep fell to 261.11 +/- 61.11 minutes from 417.13 +/- 52.04 minutes while REM absolute and percentage of total sleep dropped from 109.88 +/- 28.47 minutes to 51.44 +/- 17.92 minutes, and 22.25 +/- 3.73% to 16.33 +/- 3.17% respectively. In response to a call, mean salivary cortisol levels increased from pre-call values by 0.426 +/- 0.202 ug/dL (p<.001). Salivary c-reactive protein levels also showed significant increases with a small effect size, though due to secretion kinetics, call response is not the likely cause. The results of this study demonstrate the presence of a significant shift in autonomic control from parasympathetic (PSNS) dominance to sympathetic control and PSNS withdrawal which evokes a cortisol-mediated stress response of comparable magnitude to literature standards for normal waking fluxes. Sleep volume, and arguably the most critical stage of sleep, rapid eye movement, are significantly impacted and the links between cognitive performance and both total and overall REM sleep indicate that call response does not just impact the cardiovascular system but may in fact be reducing mental acuity of firefighters. This is important as it has the potential to impact both self and team health and safety, not only during night time call response, but at the firefighters’ day jobs which they regularly proceed to the very same morning following a call, evidently with significant deprivation in sleep. / Graduate

This project developed, analyzed, and quantified the thermal environment for four fire scenarios created in a modified standard room. Eight propane burners were placed in four different configurations while temperature and flux measurements were collected. Fire environments were intended to simulate flashover, indirect flame exposure, and wildland fires. The results will be used for the selection of a fire environment for a full-scale garment flammability test for the Navy Clothing and Textile Research Facility.

Firefighting is a strenuous occupation that requires high-intensity work, resulting in prolonged periods of stress and physical exertion. The physical demand of performing firefighting tasks is augmented by the weight of personal protective equipment (PPE) worn (i.e., load carriage: LC) and the use of a self-contained breathing apparatus (SCBA). These factors have been shown to increase metabolic demand at submaximal workloads and decrease maximal aerobic capacity in laboratory settings. However, there is limited research evaluating the effects of these factors on occupational performance. Therefore, the primary purpose of this study was to quantify the detrimental effect of LC only and LC+SCBA on firefighter occupational performance. In addition, it is important to identify fitness characteristics and physiological outcomes that are correlated to the decrement in performance produced by the PPE. This information will guide practitioners in selecting appropriate training strategies to effectively prepare firefighters to perform occupational tasks in gear. Thus, a secondary aim was to evaluate the relationships between fitness and pulmonary outcomes versus the decrement in occupational performance produced by the PPE. Twenty-one male firefighter recruits (Age: 28.6 ± 4.3 yr; Height: 178.6 ± 7.2 cm; Mass: 94.1 ± 15.4; Body Fat: 17.8 ± 8.4%) participated in this study. Occupational physical ability was assessed by time to complete a simulated fire ground test (SFGT). The SFGT was composed of the following tasks: stair climb, charged hose drag, equipment carry, ladder raise, forcible entry, search, and victim rescue. The recruits participated in six testing sessions. First, two SFGT familiarization trials were performed on separate days. During the next three testing sessions, the firefighter recruits performed the following SFGT conditions in a randomized order: control condition (PT clothes), LC only condition, and PPE+SCBA (SCBA) condition. Baseline and post-SFGT pulmonary and physiological data were collected. To describe within group differences between SFGT conditions, relative difference scores were calculated as follows: % difference = (([experimental trial outcome – PT trial outcome] / PT trial outcome) x 100). Statistical differences between the SFGT conditions were assessed with repeated measures ANOVA. To evaluate the relationship between fitness outcomes versus the decrement in SFGT performance, fitness testing data were obtained from the recruit academy and included: 1.5 mile run time, maximal push-ups, maximal sit-ups, maximal pull-ups, and prone plank time. In addition, the recruits completed a battery of fitness tests in their sixth testing session. The absolute difference in time to complete the SFGT between conditions was calculated as: experimental SFGT time - PT time. Bivariate correlations were used to assess the relationship between the absolute difference in SFGT time versus fitness outcomes. The LC+SCBA trial took 44.5 ± 15.5% longer (345.9 ± 43.7 s; p < .001) and the LC only trial took 38.3 ± 12.6% longer (331.2 ± 39.3 s; p < .001) to complete the SFGT than the PT trial (241.0 ± 33.3 s). The LC+SCBA trial took longer to complete the SFGT than the LC only trial (p = .046). Post-SFGT RPE was higher in the LC+SCBA trial (6.7 ± 1.7) and LC only trial (6.3 ± 1.5) compared to the PT trial (4.6 ± 1.8; p < .001). Absolute aerobic capacity, lower body power, anaerobic power and capacity, abdominal muscular endurance, and upper body strength were significantly correlated to the decrement in SFGT performance on some tasks caused by the PPE. In summary, PPE increases the intensity of performing fire ground tasks. To enhance occupational performance, it is imperative that firefighters optimize specific physical fitness attributes to reduce the relative stress produced by the PPE.

Sudden cardiac arrest continues to be a major cause of firefighter deaths during training due to a lack of individual firefighter adherence to National Fire Protection Association (NFPA) standards. These standards identify requirements for fire departments to create and maintain fitness programs. Existing research has not identified any relationships between training fatalities and individual firefighter adherence to NFPA 1583, Standard on Health-Related Fitness Programs for Fire Department Members. Using self-determination theory as the foundation, the purpose of this cross-sectional correlation study was to investigate whether individual firefighter adherence to NFPA 1583 has a measurable effect on training fatalities. Survey data were collected from 441 paid firefighters from 7 fire departments located in a rural county in a southern U.S. state. Data were analyzed using multiple linear regression. Results indicated that adherence to NFPA 1583 has a statistically significant relationship with reduced firefighter training fatalities (p = .000). Recommendations include examining adherence policies to all elements of the NFPA 1583 standard, not just chapters 5 through 8 in the publication. These include chapter 1 administration, chapter 2 referenced publications, chapter 3 definitions, and chapter 4 program organization specifications. The study results may be used by fire department training divisions to improve the health and safety of firefighters.