Objectives: Quantify the effects of cold water immersion of the ankle on fractioned response time of the dominant lower limb. Design and Setting: A 2x2x5x5 crossover design with repeated measures on time and treatment directed data collection. The independent variables were gender, treatment, time (pretreatment, and post 15 seconds, 3 minutes 6 minutes and 9 minutes) and trial (5 trials for each time group). Response time (Tresp), reaction time (Treac), trial and surface temperature were measurement variables. Subjects: Thirty-six subjects, 18 females and 18 males were recruited from a physically active volunteer college student population. Measurements: Fractioned response time was tested following a 20 minute treatment. Response time and Treac were recorded by the reaction timer, and Tmov was calculated by taking the difference between Tresp and Treac. For each time/subject the high and low Tresp were discarded and the middle three trials were averaged and used for statistical analysis. A 2x2x5 ANOVA was used to determine overall differences between gender, treatment and time followed by Newman-Keuls multiple comparison tests. Results: Males were faster than females for Tresp, Treac and Tmov. Movement time and Tresp were slower with cold water immersion, but Treac was unaffected. Movement time and Tresp were fastest pretreatment, and slowest during the post 15-second time group. Though both Tmov and Tresp progressively sped up from the post 15-second through the post 9-minute time group, they did not return to pretreatment values when data collection discontinued. Conclusions: Immersing the dominant ankle in cold water for 20 minutes increases Tmov of the dominant lower limb; thereby increasing fractioned response time (Tresp).

Master of Science / Department of Kinesiology / Thomas J. Barstow / Purpose: Oxygen uptake (VO2) has been shown to be controlled by a nonlinear system, yet the VO2 response to ramp style exercise appears linear. We tested the hypothesis that an integrative model incorporating nonlinear parameter values could accurately estimate actual VO2 responses to ramp style exercise. Methods: Six healthy, men completed three bouts of varying ramp rate exercise (slow ramp (SR): 15 W/min, regular ramp (RR) 30 W/min, fast ramp (FR) 60W/min) and four bouts of extended-step incremental exercise, where each step lasted 5-15 min or until volitional fatigue on a cycle ergometer on separate days. The step-responses were then fit with a simple monoexponential starting at time zero (MONO) or allowing a time delay and using only the first 5 min of data (5TD). The resulting VO2 parameters from the step protocol were incorporated into an integrative model for the estimation of the VO2 response to each of the rates of ramp incremental exercise. The parameters from the actual and model ramp protocols were compared with 2 way repeated-measures ANOVAs. Results: Both Gain (G) and Mean Response Time (MRT) (or time constant) values increased significantly across work rate transitions (mean±SD; Gain:10.0±0.9, 11.6±1.1, 13.1±1.3, 17.6±3.3 ml O2/min/W; MRT:39.4±7.7, 54.0±5.4, 79.6±15.0, 180.1±56.2 s). Up to maximalVO2 the models over-estimated the actual VO2 response for FR (Gain: ACT 8.7±1.0, MONO 9.9±0.4, 5TD 10.3±0.3 ml O2/min/W). Up to 80% maximal VO2 the models accurately predicted the actual VO2 response across all ramp rates (Gain: ACT 10.7±1.1, 10.2±0.5, 9.2±1.0; MONO 11.0±0.8, 10.3±0.6, 9.2±0.5; 5TD 10.4±0.4, 10.2±0.3, 9.8±0.2 ml O2/min/W, values are listed SR,RR,FR). Conclusions: When variable parameter values (G and either MRT or time constant and time delay) were utilized by an integrative model, accurate estimations of the VO2 response to ramp incremental exercise were possible regardless of ramp rate (up to 80% maximal VO2). The increases in both G and MRT (or time constant) appear to balance each other to produce the quasi-linear VO2 responses.

The Domain Name System (DNS) is an integral part of making the internet a more human-friendly place. However, it comes with the cost of an added abstraction layer that introduces extra latency in many aspects of the modern computing experience - a great selling point for many DNS services. In this thesis we look at the performance of DNS services and servers through the scope of 51 unique free, public and popular DNS servers. We use a specifically designed tool, DNSHoarder, to collect 714,000 datapoints of 250 different hostnames of varying popularity over seven days. From this data we find most DNS servers to exhibit a similar relative distribution of response times and performance differences between IPv4 and IPv6 to be minor or nonexistent. We also find network distance and quality to have a big effect on the performance of DNS as well as network latency to be a major limiting factor in further DNS performance improvements.

A sample of 61 subjects from an introductory psychology class was administered a battery of psychological tests, among them the Rorschach and the MMPI. The purpose was to determine the behavioral correlates, if any, of the two Rorschach variables, Mean Reaction Time, and Fluctuation in Time of First Response. This was accomplished by using multivariate statistical techniques, i.e. a factor analysis followed by a stepwise multiple regression. The results were ambiguous. While not statistically significant, they suggest that the MMPI variables of Social Introversion and Psychopathic Deviant are more closely related to the two dependent variables than previous literature would suggest. One variable, anxiety, which has been shown by previous research to be associated with Mean Reaction Time, was found to be not associated by the present investigation. Explanations and suggestions for further research were discussed.

Methods for performing response time analysis of real-timesystems are important, not only for their use in traditionalschedulability testing, but also for deriving bounds on outputtiming variations in control applications. Automatic controlsystems are inherently sensitive to variations in periodicityand end-to-end delays. Therefore, real-time performance needsto be considered during control design. For this purpose, anyreal-time analysis of a potential control implementation shouldproduce results that can easily be used to examine how theimplementation affects control performance. To find the maximumresponse time variation for a task, bounds on both minimum andmaximum response times are needed. A tight bound on thismaximum variation is useful in the analysis of controlperformance and can also be used to improve the results of someiterative response time analysis methods. In this thesis, threemethods for response time analysis are developed. While earlier research has focused on bounding maximumresponse times, one of the analysis methods in this thesisallows a computation of the minimum response times ofindependent fixed priority scheduled tasks. The analysis findsthe largest lower bound of response times for such tasks, whichleads to a tighter bound on the response time variations. Asecond analysis method allows exact computation of maximumresponse times for tasks whose arrival times are related byoffsets. The method is a complement to schedule simulationbased analysis, which it outperforms for systems with tasksthat may experience release jitter. A common design principle for distributed real-time systemsis to let the completion of one task trigger the start of oneor more successors. A third method supporting the analysis oftasks in such systems is described. The method extends andimproves earlier methods as it allows a generalized systemmodel and also results in tighter bounds than the originalmethods. This method has been implemented as part of a toolsetthat enables an integrated approach to the design and analysisof control systems and their implementation as distributedreal-time systems. As part of the thesis, models for describingdistributed control systems have been developed. The toolset,which is based on these models, uses the derived response timebounds in a control system performance analysis based onsimulation. The use of the toolset is exemplified in a smallcase study. <b>Keywords:</b>real-time systems, scheduling, response time,fixed priority, control, jitter, offset, schedulabilityanalysis

Ambulance response time is a key measure used to assess EMS system performance. However, the speed with which ambulances respond to emergencies can be highly variable. In some cases, this is due to geography. In dense urban areas for example, the distances traveled are short, but traffic and other hindrances such as traffic calming measures and high rise elevators cause delays, while rural areas involve greater distances and longer travel times. There are two major components of response time: first, pre-travel delay to prepare for ambulance dispatch, and second the actual travel time to the callers location. Response time standards are often established in order to provide fast and reliable service to the most severely ill patients. Standards typically specify the percentage of time an emergency response team can get to a call within a certain time threshold. This is referred to as “coverage”. This thesis deals with the development of a new response time model that predicts not only the mean response time, but estimates its variability. The models are developed based on historical data provided by the Region of Waterloo EMS and will permit the Region to predict EMS coverage. By analyzing the historical data, we found that response times from EMS stations to geographical locations within the Region of Waterloo are characterized by lognormal distributions. For a particular station – location pair we can thus use this information to predict coverage if we are able to specify the parameters of the distribution. We do this by characterizing the travel time and pre-travel delay times separately, and then adding the two to estimate coverage. We will use a previously proposed model that estimates the mean travel time from a station to a demand point as a function of road types traversed. We also compare the results of this model with another well known model and show that the first model is suitable to apply to the Region of Waterloo. In order to estimate the standard deviation of the response time, we propose a simple but effective model that estimates the standard deviation as a function of mean response time.

Ambulance response time is a key measure used to assess EMS system performance. However, the speed with which ambulances respond to emergencies can be highly variable. In some cases, this is due to geography. In dense urban areas for example, the distances traveled are short, but traffic and other hindrances such as traffic calming measures and high rise elevators cause delays, while rural areas involve greater distances and longer travel times. There are two major components of response time: first, pre-travel delay to prepare for ambulance dispatch, and second the actual travel time to the callers location. Response time standards are often established in order to provide fast and reliable service to the most severely ill patients. Standards typically specify the percentage of time an emergency response team can get to a call within a certain time threshold. This is referred to as “coverage”. This thesis deals with the development of a new response time model that predicts not only the mean response time, but estimates its variability. The models are developed based on historical data provided by the Region of Waterloo EMS and will permit the Region to predict EMS coverage. By analyzing the historical data, we found that response times from EMS stations to geographical locations within the Region of Waterloo are characterized by lognormal distributions. For a particular station – location pair we can thus use this information to predict coverage if we are able to specify the parameters of the distribution. We do this by characterizing the travel time and pre-travel delay times separately, and then adding the two to estimate coverage. We will use a previously proposed model that estimates the mean travel time from a station to a demand point as a function of road types traversed. We also compare the results of this model with another well known model and show that the first model is suitable to apply to the Region of Waterloo. In order to estimate the standard deviation of the response time, we propose a simple but effective model that estimates the standard deviation as a function of mean response time.

This paper study the influence of surface properties of encapsulated CLC on response time and reflectance via polymerization induced phase separation. The cured polymer layer, which is composed of the mixture of EMA and TRI, adhere to the inside of the non-treated glass substrate and change the surface properties to vertical alignments. Different boundary conditions caused by various UV curing intensity and cell gap lead to different electro-optical properties for CLC display. With a proper boundary structure, the transition time from homeotropic to planar of CLC can be reduced obviously with slightly reduced reflectance.

In this study we have successfully developed the techniques of time-resolved electro-luminescence (EL) and optical beam induced current (OBIC) microscopy for the mapping of photonic devices. We have applied the techniques to examine various photonic devices, including light emitting diodes (LED), organic light emitting diode (OLED), and coplanar waveguide (CPW) devices. The key development in time-resolved microscopy is the technique of modulation. By measuring the phase delay between the modulation source and the output signal, the response time of the observed devices can be extracted. In electro-luminescence mapping, the phase delay is measured between the applied sinusoidal voltage and the emitted EL, while in OBIC mapping the phase delay is measured between the modulated laser beam and the resulting photocurrent. The phase delay measurements are performed with a lock-in amplifier. In this way, large enhancement in signal-to-noise ratio can also be obtained. Additionally, the technique of varying scanning rate is also developed to synchronize the data acquisition between the LSM and the lock-in amplifier, a key enabling advancement in this thesis study.

The major purpose of LED is the electroluminescence. We use the time-resolved electroluminescence (TR-EL) method to measure the response time of LED in our experiments. In addition, typical diode has optical beam induced current (OBIC) characteristic in its depletion region. Combining upon physical reaction we can compare TR-EL and OBIC in the same LED. We are using the high frequency function generator, pulsed laser with high repetition rate, laser scanning confocal microscopy and a high frequency phase sensitive lock-in loop to achieve temporal resolution. The response time of LED can be measured in two different physical characteristic.