Material and Design Considerations for a Portable Ultra-Violet (UV) Light Emitting Diode (LED) Water Purification Device

Department of Defense personnel often deploy to austere environments where clean water is not readily available. Ultraviolet (UV) radiation through the use of light emitting diodes (LEDs) in a portable device offers a potential method for expedient water treatment. This research studied the application of one diode, low power, UV LEDs and nine diode, high power, UV LEDs within a portable steel reactor and Teflon reactors of three different wall thicknesses. Reactor efficiency was determined through measuring and comparing the rate constants for Advanced Oxidation of hydrogen peroxide with yellow tartrazine as a witness dye. Experiments conducted with low power UV LEDs indicate that the medium thickness reactor has a statistically significant higher rate constant than the steel and thin cylinder reactors. All high power UV LED tests had rate constants ten times higher than the low UV LEDs, but exhibited no significant difference between materials or thicknesses. Additionally, this research examined the microorganism inactivation in the optimum reactor by exposing E. coli to UV radiation. The experiments demonstrated complete reduction of E. coli at a flow rate up to 15 mL/min, and a 2-Log reduction at 20 mL/min, thus demonstrating proof of concept for future portable UV LED disinfection units

Thermoelectric Power Generation for Heat Recovery in Automotive Industries

Researches on integrating thermoelectric power generator into various vehicle platform have witness a surge in solid demand of improving thermal efficiency and CO2 emission reduction from automotive industries. Many prototypes were built and tested in different segments of the car. Position at exhaust gas recirculation valve and downstream of catalyst are preferred by car manufacturers as easiness of installation. Up to 4% improvement of fuel economy has been claimed under an ideal road driving cycle. Much focuses on the lightweighting of the thermoelectric power generator whilst producing stable electric power output under an intermittent working load. However, major barriers to real application still exist due to low conversion efficiency of thermoelectric material and poor heat exchanger system design. Although heat source can be high up to 800 K, actual temperature at thermoelectric legs are much less than that. Thermal losses are inevitable through the heat exchanger route and effectiveness of heat transfer become the key to system development in future. Thermoelectric material working in higher temperature could be a breakthrough and game changer for waste heat recovery in automotive industries

PENGARUH TEOLOGI EKARISTI IGNATIUS ANTIOKHIA TERHADAP ENSIKLIK ECCLESIA DE EUCHARISTIA

In the Encyclical of Ecclesia de Eucharistia, John Paul II states that Eucharist unites Church with God. In Eucharist, the presence of Christ is real. As a consequence, understanding Eucharist as merely series of rubrics is a form of reduction of the Eucharist. In the Encyclical, the Pope recalled the thought of Ignatius of Antioch on the Eucharist. Both John Paul II and Ignatius stated that Eucharist is a thanksgiving on the salvation of God. Eucharist is an invitation of God for the Church to live in the presence of God. The living experience of loving God supports the Church in transforming the world. The Church receives the power of Loving God in the Eucharist that strengthens each witness to live an exemplary Christian life here and now

Correlated noise in networks of gravitational-wave detectors: subtraction and mitigation

One of the key science goals of advanced gravitational-wave detectors is to observe a stochastic gravitational-wave background. However, recent work demonstrates that correlated magnetic fields from Schumann resonances can produce correlated strain noise over global distances, potentially limiting the sensitivity of stochastic background searches with advanced detectors. In this paper, we estimate the correlated noise budget for the worldwide Advanced LIGO network and conclude that correlated noise may affect upcoming measurements. We investigate the possibility of a Wiener filtering scheme to subtract correlated noise from Advanced LIGO searches, and estimate the required specifications. We also consider the possibility that residual correlated noise remains following subtraction, and we devise an optimal strategy for measuring astronomical parameters in the presence of correlated noise. Using this new formalism, we estimate the loss of sensitivity for a broadband, isotropic stochastic background search using 1 yr of LIGO data at design sensitivity. Given our current noise budget, the uncertainty with which LIGO can estimate energy density will likely increase by a factor of ~4--if it is impossible to achieve significant subtraction. Additionally, narrowband cross-correlation searches may be severely affected at low frequencies f < 45 Hz without effective subtraction.Comment: 16 pages, 8 figure

Who witnesses The Witness? Finding witnesses in The Witness is hard and sometimes impossible

We analyze the computational complexity of the many types of pencil-and-paper-style puzzles featured in the 2016 puzzle video game The Witness. In all puzzles, the goal is to draw a simple path in a rectangular grid graph from a start vertex to a destination vertex. The different puzzle types place different constraints on the path: preventing some edges from being visited (broken edges); forcing some edges or vertices to be visited (hexagons); forcing some cells to have certain numbers of incident path edges (triangles); or forcing the regions formed by the path to be partially monochromatic (squares), have exactly two special cells (stars), or be singly covered by given shapes (polyominoes) and/or negatively counting shapes (antipolyominoes). We show that any one of these clue types (except the first) is enough to make path finding NP-complete ("witnesses exist but are hard to find"), even for rectangular boards. Furthermore, we show that a final clue type (antibody), which necessarily "cancels" the effect of another clue in the same region, makes path finding $\Sigma_2$-complete ("witnesses do not exist"), even with a single antibody (combined with many anti/polyominoes), and the problem gets no harder with many antibodies. On the positive side, we give a polynomial-time algorithm for monomino clues, by reducing to hexagon clues on the boundary of the puzzle, even in the presence of broken edges, and solving "subset Hamiltonian path" for terminals on the boundary of an embedded planar graph in polynomial time.Comment: 72 pages, 59 figures. Revised proof of Lemma 3.5. A short version of this paper appeared at the 9th International Conference on Fun with Algorithms (FUN 2018