2,397 research outputs found
Collapse of large vapor bubbles
The refilling of propellant tanks while in a low-gravity environment requires that entrapped vapor bubbles be collapsed by increasing the system pressure. Tests were performed to verify the mechanism of collapse for these large vapor bubbles with the thermodynamic conditions, geometry, and boundary conditions being those applicable to propellant storage systems. For these conditions it was found that conduction heat transfer determined the collapse rate, with the specific bubble geometry having a significant influence
Detections and Constraints on White Dwarf Variability from Time-Series GALEX Observations
We search for photometric variability in more than 23,000 known and candidate
white dwarfs, the largest ultraviolet survey compiled for a single study of
white dwarfs. We use gPhoton, a publicly available calibration/reduction
pipeline, to generate time-series photometry of white dwarfs observed by GALEX.
By implementing a system of weighted metrics, we select sources with
variability due to pulsations and eclipses. Although GALEX observations have
short baselines (< 30 min), we identify intrinsic variability in sources as
faint as Gaia G = 20 mag. With our ranking algorithm, we identify 49 new
variable white dwarfs (WDs) in archival GALEX observations. We detect 41 new
pulsators: 37 have hydrogen-dominated atmospheres (DAVs), including one
possible massive DAV, and four are helium-dominated pulsators (DBVs). We also
detect eight new eclipsing systems; five are new discoveries, and three were
previously known spectroscopic binaries. We perform synthetic injections of the
light curve of WD 1145+017, a system with known transiting debris, to test our
ability to recover similar systems. We find that the 3{\sigma} maximum
occurrence rate of WD 1145+017-like transiting objects is < 0.5%.Comment: 17 pages, 13 figure
NASA systems autonomy demonstration project: Advanced automation demonstration of Space Station Freedom thermal control system
The NASA Systems Autonomy Demonstration Project (SADP) was initiated in response to Congressional interest in Space station automation technology demonstration. The SADP is a joint cooperative effort between Ames Research Center (ARC) and Johnson Space Center (JSC) to demonstrate advanced automation technology feasibility using the Space Station Freedom Thermal Control System (TCS) test bed. A model-based expert system and its operator interface were developed by knowledge engineers, AI researchers, and human factors researchers at ARC working with the domain experts and system integration engineers at JSC. Its target application is a prototype heat acquisition and transport subsystem of a space station TCS. The demonstration is scheduled to be conducted at JSC in August, 1989. The demonstration will consist of a detailed test of the ability of the Thermal Expert System to conduct real time normal operations (start-up, set point changes, shut-down) and to conduct fault detection, isolation, and recovery (FDIR) on the test article. The FDIR will be conducted by injecting ten component level failures that will manifest themselves as seven different system level faults. Here, the SADP goals, are described as well as the Thermal Control Expert System that has been developed for demonstration
A Redemption of Meaning in Three Novels by Italo Calvino
In this thesis I present three readings of Italo Calvino’s later novels: Invisible Cities (1972), If on a winter’s night a traveler (1979), and Mr. Palomar (1983). My primary aim is to defend Calvino against dominant scholarly interpretations that position him as a Postmodern nihilist, a literary trickster interested solely in toying with the mechanics of language. My analysis of Calvino’s work re-envisions him as a special breed of Postmodernist concerned with humanity’s ability to create spaces for meaning in spite of an indifferent cosmos. Drawing from psychoanalytic theory, cognitive science, analytic philosophy, and phenomenology, I synthesize my own critical lens to demonstrate Calvino’s ecstatic faith in human creativity. I claim that Calvino’s later novels contain a fundamentally ethical message: they call on us to live our lives with the intensity and vigilance of the artist, to see the world as a landscape for the collective life of our minds, to endure “the inferno of the living” through acts of creation
Using Blockchain Technology to Facilitate Anti-Money Laundering Efforts
Money laundering can be defined as any act or attempted act to conceal or disguise the identity of illegally obtained proceeds so that they appear to have originated from legitimate sources (Money Laundering, 2016). It is difficult to determine the magnitude of money laundering because these illicit financial flows remain hidden (Schott, 2006). A report issued by the United Nations Office on Drugs and Crime (UNODC) quoted that the total of all criminal proceeds amounted to $2.1 trillion in 2009. The study also shows that “Less than 1 percent of global illicit financial flows are currently seized and frozen” (Pietschmann & Walker, 2012). This is concerning because money laundering not only enables the operation of criminal organizations such as drug and human traffickers but can also significantly distort the economies in which they enter.
The Financial Action Task Force (FATF) is an inter-governmental policy-making body that has helped to promote anti-money laundering efforts since its formation in 1989. It has issued 40 recommendations to fight money laundering and nine special recommendations to combat terrorist financing which have been adopted by 32 countries (About - Financial Action Task Force, 2016). Unfortunately, implementing these strategies has proved to be difficult for both developed and lesser developed countries. According to a study conducted by PricewaterhouseCoopers in 2016, “over the last few years, in the U.S. alone, nearly a dozen global financial institutions have been assessed fines in the hundreds of millions to billions of dollars for money laundering and/or sanctions violations (PricewaterhouseCoopers, 2016). It stands to say that if financial institutions are having difficulties implementing frameworks to prevent and detect money laundering, then our enforcement agencies are unable to adequately address the issue as well.
A new hurdle that enforcement agencies have had to face is the emergence of Bitcoin, as well as other cryptocurrencies, that can be described as “a digital currency and online payment system in which encryption techniques are used to regulate the generation of units of currency and verify the transfer of funds, operating independently of a central bank” (Swan, 2015). Being an often unrecognized currency, many banks and financial institutions have not had to worry about modifying their compliance programs. The biggest benefit of cryptocurrencies to money launderers is its decentralized nature. There is no governing authority, as members of the network handle issuances and payments. Once a disruptive technology, Bitcoin is beginning to lose momentum for a number of reasons and some its strongest proponents are now referring to it as nothing more than an experiment. The purpose of this paper is not to examine Bitcoin, but rather its underlying technology that has been found to be the actual value: blockchain. After providing a brief overview of the technology and the hurdles that financial institutions face when implementing anti-money laundering compliance programs, the possible ways in which blockchain can help alleviate these difficulties will be examined
The Health Care Gap in Rural Malaysia
Malaysia has made significant progress over the past several decades in improving health care services. However, providing rural populations with quality and accessible health care remains a challenge, leaving Malaysia to investigate new solutions in health care delivery to rural populations. This article examines the current state of rural health care in Malaysia and suggests possible solutions to bridge the health disparities between urban and rural populations
The recoverability of fingerprints on paper exposed to elevated temperatures - Part 1: comparison of enhancement techniques
This research investigates the recoverability of fingerprints which have been exposed to elevated temperatures in order to mimic the environment a piece of paper may be exposed to within an arson scene. Arson is an expensive crime, costing the UK economy, on average, ÂŁ53.8 million each week [1]. Anything which may give rise to the identity of the fire setter should be analysed and as such, unburnt paper may be a potential source of fingerprints. While it is true that even a moderate fire will obscure and render partially useless some types of evidence, many items, including fingerprints, may still survive [2-4]. This research has shown that fingerprints are still retrievable from paper which has been subjected to the maximum testing conditions of 200ËšC for 320min. In fact, some fingerprints naturally enhance themselves by the heating process. This investigation has also shown that the most effective enhancement technique was found to be 1,8-diazafluoren-9-one (DFO) for exposure temperatures upto 100ËšC. Physical developer (PD) is the most effective enhancement technique for exposure temperatures from 100ËšC to 200ËšC. For porous surfaces, there are fingerprint development techniques which are effective at enhancing fingerprints exposed upto a temperature of 200ËšC, irrespective of the firefighting extinguishing technique, as PD, in addition to developing fingerprints exposed to high temperatures, is one of the few processes which will enhance fingermarks on wetted surfaces
A comparison of six fingerprint enhancement techniques for the recovery of latent fingerprints from unfired cartridge cases
This work compared the effectiveness of six different enhancement methods on six different sizes of brass cartridges. One sebaceous fingerprint was deposited onto twenty-five of each size of cartridge to enable a statistical evaluation of the enhancement methods for each cartridge size to be undertaken. The enhancement methods compared were superglue followed by BY40, superglue followed by gun blue followed by BY40, gun blue only, superglue followed by palladium deposition, palladium deposition only, and powder suspension. The six different cartridges used in this study were .22s, .32s, 9mm, .38s, ribbed shotgun, and smooth shotgun. The study found that more potentially identifiable fingerprints were enhanced on the larger cartridge cases. This was due to the surface area on the smaller cartridges, and in particular the .22s provided little ridge detail. Two techniques provided the best results - superglue followed by gun blue followed by BY40, and superglue followed by palladium deposition. This showed that the combination of the cyanoacrylate fuming and the metal oxidation reactions is increasing the yield of potentially identifiable fingerprints compared with the use of the techniques separately. Both techniques were also found to give reproducible results. These two enhancement techniques were also compared statistically and no statistical difference in their effectiveness was found suggesting both techniques are equally as effective at enhancing fingerprints on brass cartridge cases
Impact of Spray Coating on the Performance of Hydrophobic Membranes
Membrane distillation (MD) is a rapidly emerging water treatment technology used to combat the global water crisis. Membrane pore wetting is a primary barrier to widespread industrial use of MD. The primary causes of membrane wetting are membrane fouling and an exceedance of liquid entry pressure. The development of different types of polymer membranes and the use of pretreatment have led to significant movement towards the prevention of wetting in MD. We sought to take a new approach to combat membrane wetting that involves coating these membranes with hydrophilic chemical compounds, which consequently would decrease their air permeability. Pulling data from our HVAC group’s latest papers, we used two different compounds for our coats: Graphene Oxide (GO) and Pebax 1657. After heating and mixing, these compounds were spray coated onto polypropylene membranes at 10 mL, 20mL, and 30 mL worth of solution. 7 membranes with area 38mm x 44 mm were created, including one uncoated for control, and placed into a porometer to measure the gas permeability. We discovered that 30 mL of Pebax and GO made an equal, strong difference in combating wettability. In the future, these membranes can be used in membrane distillation to measure the performance of their coats’ ability to combat wetting. These experiments serve as a big step in the move toward the industrialization of membrane distillation with the goal of overcoming the freshwater shortages of the world
Application of Problem Based Learning and Mastery Learning to Multimedia Education
The current state of education and the workforce demands a special kind of learner capable of creativity, communicating effectively, analytical skill application, critical thinking, and problem solving. Whereas these skills are important, it is also a necessity for learners to be masters of the knowledge and skills that they have acquired. Traditional educational methods have proven to be somewhat ineffective in producing these results. Problem based learning has proven worthy in handling some of the load, however, mastery learning has been abandoned long ago for reasons in spite of its effectiveness. Through given examples and careful design, the educator will witness practical application of these models in tandem to create efficient, effective, and appealing instruction that suits the needs of education and the modern workforce
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