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- All Subjects: Performance
- Creators: College of Health Solutions
- Creators: Srinivasan, Devarajan
Characterization and analysis of long term field aged photovoltaic modules and encapsulant materials
This study is attempting to compare four different silver leaching test methods, to study the silver leaching potential of the silver impregnated membranes, conducting the advantages and disadvantages of the leaching methods. An In-situ reduction Ag loaded RO membrane was examined in this study. A custom waterjet test was established to create a high-velocity water flow to test the silver leaching from the nanocomposite membrane in a relative extreme environment. The batch leaching test was examined as the most common leaching test method for the silver composite membrane. The cross-flow filtration and dead-end test were also examined to compare the silver leaching amounts.
The silver coated membrane used in this experiment has an initial silver loading of 2.0± 0.51 ug/cm2. The mass balance was conducted for all of the leaching tests. For the batch test, water jet test, and dead-end filtration, the mass balances are all within 100±25%, which is acceptable in this experiment because of the variance of the initial silver loading on the membranes. A bad silver mass balance was observed at cross-flow filtration. Both of AgNP and Ag ions leached in the solution was examined in this experiment. The concentration of total silver leaching into solutions from the four leaching tests are all below the Secondary Drinking Water Standard for silver which is 100 ppb. The cross-flow test is the most aggressive leaching method, which has more than 80% of silver leached from the membrane after 50 hours of the test. The water jet (54 ± 6.9% of silver remaining) can cause higher silver leaching than batch test (85 ± 1.2% of silver remaining) in one-hour, and it can also cause both AgNP and Ag ions leaching from the membrane, which is closer to the leaching condition in the cross-flow test.
Part 1 characterizes soiling losses using various techniques to understand the effect of soiling on photovoltaic modules. The higher the angle of incidence (AOI), the lower will be the photovoltaic (PV) module performance. Our research group has already reported the AOI investigation for cleaned modules of five different technologies with air/glass interface. However, the modules that are installed in the field would invariably develop a soil layer with varying thickness depending on the site condition, rainfall and tilt angle. The soiled module will have the air/soil/glass interface rather than air/glass interface. This study investigates the AOI variations on soiled modules of five different PV technologies. It is demonstrated that AOI effect is inversely proportional to the soil density. In other words, the power or current loss between clean and soiled modules would be much higher at a higher AOI than at a lower AOI leading to excessive energy production loss of soiled modules on cloudy days, early morning hours and late afternoon hours. Similarly, the spectral influence of soil on the performance of the module was investigated through reflectance and transmittance measurements. It was observed that the reflectance and transmittances losses vary linearly with soil density variation and the 600-700 nm band was identified as an ideal band for soil density measurements.
Part 2 of this thesis performs statistical risk analysis for a power plant through FMECA (Failure Mode, Effect, and Criticality Analysis) based on non-destructive field techniques and count data of the failure modes. Risk Priority Number is used for the grading guideline for criticality analysis. The analysis was done on a 19-year-old power plant in cold-dry climate to identify the most dominant failure and degradation modes. In addition, a comparison study was done on the current power plant (framed) along with another 18-year-old (frameless) from the same climate zone to understand the failure modes for cold-dry climatic condition.
Recovery from exercise has become an evolving aspect of all sports performance. Increased research has led numerous individuals to understand and utilize the modalities that have become available. Methods such as Cold Water Immersion (CWI), Contrast Water Therapy (CWT), and Hot Water Immersion (HWI) are some of the modalities growing in popularity as well as utilization by athletes across all sports. This paper aims to examine and analyze evidence across several research journals that evaluate the effectiveness and also application of these recovery methods. Cold and heat exposures on the body can have a drastic positive impact on athletic performance. However, without the correct knowledge and guidance, these methods can augment, mitigate, and even diminish the effects of adaptation and exercise. This thesis aims to examine research journals and extract specific practices based on empirical evidence. This is to form proper deliverables and protocols for athletes to use for ideal adaptations and recovery for performance.
This thesis reviewed variables of baseball mechanics and performance as discussed in current literature. This included investigating factors of biomechanics, the health of players, and comparisons across demographics. At the biomechanical level, components of the kinetic chain were observed as the energy transferred from the lower body to the upper body. Additionally, the upper body appeared to compensate for deficits in the rotation of the trunk. Injuries to the abdominal and low back were correlated with trunk rotation, while arm injuries were traced back to overuse and fatigue. When considering experience level, variation tended to decrease. Youth players demonstrated different patterns of fatigue and different injury correlates compared to adults. At a geographic level, American pitchers may be associated with an increased risk of elbow injuries, with Japanese and Korean pitchers to shoulder injuries; these differences are thought to be due to differences in instruction. Applying this research and findings to current baseball players may help guide training and performance or continue research.