Monday, August 31, 2009

INSPIRE Student Interns Learning Flight Test First-Hand

Student interns in NASA's INSPIRE program are learning first-hand about the start-to-finish lifecycle of flight testing experimental aircraft this summer by working in teams to build, flight test and analyze data from two small-scale remote-controlled airplanes at NASA's Dryden Flight Research Center.

As with all experimental flight research at NASA Dryden, the students proceeded through a series of technical reviews, safety analyses, development of mission rules and flight operations before conducting actual data-collection flights. After their arrival June 8, the students began 2 ½ weeks learning aerodynamics, systems engineering, safety, and Dryden's flight approval process. They also measured the geometry of the model aircraft selected for the project, and used their new knowledge to estimate its performance.

The students then took an additional 2 ½ weeks to make flight cards detailing each of the test points they wished to accomplish, perform static thrust testing and a combined systems test. In addition, they assessed programmatic and human risks and found mitigations as needed. They presented these results, along with plans for safely conducting flight operations, at a formal technical briefing, a requirement to receive approval for actual flight tests.

Two identical Electrostik RXR aircraft were chosen for the student project because they were large enough to hold the sensors and for their ease of assembly. The aircraft were then modified with a sensor suite from Eagle Tree Flight Systems that includes a pitot-static system, GPS, temperature probes, and accelerometers. The students installed all of the sensors and performed static thrust testing to pick the optimal propeller.

Once all the preparations and processes were completed, the student interns proceeded to conduct two rounds of actual flight tests. Thirteen flights were flown July 13 and 14 over a model aircraft flight operations area along the north edge of Rosamond Dry Lake on Edwards Air Force Base, about 10 miles from NASA Dryden. The short flights focused on aircraft performance issues, such as control-surface trim, air-data calibration, lift and drag, thrust required for level flight, turn performance and rate of climb.

As often occurs in flight testing, some technical glitches were encountered when the students were not able to get positive confirmation that the second aircraft's data collection system was working properly and had to use the other aircraft for most of the flight testing, explained NASA Dryden controls and dynamics engineer Brian Taylor, who is serving as a mentor to the students. After the students took a quick look at the data, however, they found that the second aircraft was recording flight data properly, and are now analyzing data from all of the flights to compare it with their earlier estimates. They will detail their results at a final briefing on July 30.

"The students are getting a small dose of the realities of flight research and test," commented Bradley C. Flick, Chief Engineer at NASA Dryden. "Dealing with system failures and uncertainties are commonplace and they're learning more about engineering than they would have if everything had been perfect from the start."

INSPIRE is an acronym for Interdisciplinary National Science Project Incorporating Research and Education Experience, a multi-tiered year round program designed for students in ninth-to-12th grades who are interested in science, technology, engineering, and mathematics education and careers. According to Kendra Titus, Student & Faculty Programs Coordinator at NASA Dryden's Office of Education, the INSPIRE summer internship program provides direct project experience for students who are interested in engineering careers and who will be entering their senior year in high school or their freshman year in college in the fall.

Friday, August 28, 2009

Ocean Bottom Pressure

This map shows changes in ocean bottom pressure measured by NASA's Gravity Recovery and Climate Experiment (Grace).

Red shows where pressure varies by large amounts, blue where it changes very little. Just as knowing atmospheric pressure allows meteorologists to predict winds and weather patterns, measurements of ocean bottom pressure provide oceanographers with fundamental information about currents and global circulation. They also hold clues to questions about sea level and climate.

The pressure at the bottom of the ocean is determined by the amount of mass above it.

Wednesday, August 26, 2009

aquarium fish: Guppy

The guppy prefers a hard water aquarium and can withstand levels of salinity up to 150% that of normal sea water, which has led to them being occasionally included in marine tropical community tanks, as well as in freshwater tropical tanks. Guppies are generally peaceful, though nipping behaviour is sometimes exhibited between male guppies or towards other top swimmers like platys and swordtails and occasionally other fish with prominent fins such as angelfish. Its most famous characteristic is its propensity for breeding, and it can breed in both fresh water and marine aquariums.

Guppy breeding by aquarists produces variations in appearance ranging from color consistency to fantails and "spike" swordtails. Selective breeding has created an avid "fancy guppy" collector group, while the "wild" guppy maintains its popularity as one of the hardiest aquarium fish.

Well fed adults often do not eat their own young, although sometimes safe zones are required for the fry. Specially designed livebearer birthing tanks, which can be suspended inside the aquarium, are available from aquatic retailers. These serve the dual purpose of shielding the pregnant female from further attention from the males, which is important because the males will sometimes attack the females while they are giving birth. It also provides a separate area for the newborn young as protection from being eaten by their mother. However, if a female is put in the breeder box too early it may cause her to have a miscarriage. Well planted tanks that offer a lot of barriers to adult guppies will shelter the young quite well. Java moss, Duckweed (Lemna Minor), and Water Wisteria are all excellent choices.

Thursday, August 20, 2009

Cash Machine Fraud Warning

Criminals have attached card reading devices to at least two cash point machines in the District. Essex Police and Epping Forest District Council’s Safer Communities Department has advised people to be more vigilant when obtaining cash from a cash machine and to ensure that you shield your pin number and make sure that nobody is looking over your shoulder.

Safer Communities Manager, Caroline Wiggins said: "Please be very careful before withdrawing money from cash machines in the District and check to ensure that the machine has not been tampered with."

Criminals can obtain cards and pin numbers by using a flat card reading device placed directly over the machine slot. A very small pin-head camera is sometimes also placed to read your pin number. If you notice anything unusual about a cash machine, please report it to staff from where you are obtaining money from immediately.

Monday, August 17, 2009

Global fisheries show potential for comeback

Five out of 10 global ecosystems once threatened by overfishing are on the mend, according to a new study. A collaboration of scientists from seven countries analyzed fish populations around the world and found that the mass of fish removed from the ocean every year has decreased in some fisheries.

“This improvement might well be a reflection of the call to arms that has gone out over the last five to 10 years about the state of the ocean and its needs,” said Stephen Palumbi, professor of biology, director of Stanford’s Hopkins Marine Station, and one of the 21 collaborating scientists. “It shows that fishery restrictions can actually pay off and things can get better.”

Fishing rates have dropped to at least a healthy level called maximum sustainable yield, which is the greatest amount of fish that can be harvested without depleting the population in the long term. The five ecosystems include oceans surrounding New Zealand; northwestern Australia; Iceland; the California current system stretching from Baja California to Canada; and western Canada and Alaska, up to the Bering Strait.

Well-documented decline

Scientists have presented numerous reports over the years cataloging the decline of marine ecosystems and the ominous collapse of global fisheries. A species collapse means the total mass of fish has fallen below 10 percent of original levels.

The new study, published in the July 31 edition of Science, was initiated by a disagreement between two groups of scientists. University of Washington fisheries scientist Ray Hilborn questioned methods used by a different group led by Boris Worm of Dalhousie University in Canada, which predicted in 2006 that most harvested fish species would collapse by 2048. Because the debate opened areas of common ground, the two began meeting to discuss their findings and eventually launch the new study.

The group used ecosystem models to analyze records of global catches, small-scale fishery data, trawl surveys and stock assessments, which show the status of exploited fish populations. Not all of their findings were good news; out of 166 fish stocks, 63 percent had collapsed, a figure similar to the one in the 2006 paper, Palumbi said. Five of 10 well-managed ecosystems are still in decline, including oceans surrounding southeastern Australia, the Gulf of Thailand, northern Europe, northeastern United States and eastern Canada.

Hopeful for recovery

The scientists still seem hopeful for the ecosystems’ recovery if a lower rate of harvesting is enforced. They suggest catch restrictions, closing areas, and implementing economic incentives such as sustainable fishery certification.

The authors of the paper point to a successful case in Kenya where fish populations living in coral reefs recovered after local communities closed areas and restricted fishing gear such as beach seines, which catch unwanted marine animals along with the target fish. Fish size and weight improved, leading to steep increases in fishers’ incomes.

Unfortunately, a promising global average based on the 10 studied ecosystems may hide regional variation. “These 10 ecosystems really are the elite fisheries of the world – the ones with the most funding, the most research, and the most enforcement,” Palumbi said. Recovery of fish stocks in a developing country, on the other hand, is challenging when locals lack alternative sources of food, income and employment.

The scientists also suggest joining forces of fishery management and conservation through marine protection acts. “The two together – well managed fisheries and marine protected areas – are likely to be great partners in rebuilding marine ecosystems. They’re different strategies but they’re quite complementary,” Palumbi said.

Thursday, August 13, 2009

Computer Animation of Mitosis

This invention is a computer animation model depicting the process of cell reproduction, better known as mitosis. This invention aims to make the process of learning about mitosis and its phases more memorable and retainable for students. Learning from a textbook is often a tedious task, and I hope to improve learning motivation. The invention is an animation without voice over components. This animation is run at a standard of 12 frames per second (fps). This standard is used commonly when media is to be posted to the Internet, although other fps rates are used. For example, most animated feature films run at 24 fps, allowing the film and animation to run smoothly and be choppy. 12 fps can a be just as smooth as 24 fps, but the difference is that the 12 fps will run twice as fast as 24 fps. To create the animation I used the programs Paint Shop Pro v6.02 and Animation Shop 2 to create the drawing and into compile them to a working and full running animation.

Friday, August 07, 2009

Cash Conversion

This article describes how cash in the MARS’ Federal Fund will be converted to eMARS. It will describe some of the things that may go wrong with this conversion if grant accountants are not diligent about maintaining the crosswalk in the MPS database until they are asked to submit it on June 30.

Every dollar of cash residing in the Federal Fund when financial activity in MARS ceases during the weekend of July 8 and 9 will be converted to eMARS. Ideally, every dollar that is converted to eMARS will be associated with an eMARS program structure in the MPS database.

Since late November 2005 agency grant accountants have been encouraged to appropriately deal with residual cash balances identified with closed/inactive grants that will not convert to eMARS. This activity may have involved any or all of the following:

  • Transferring cash from a state fund to cover residual cash deficits;

  • Transferring positive residual cash balances to a state fund; or

  • Consolidating positive residual cash balances in a pseudo-grant to mitigate the Federal Fund cash deficit that would result from transferring it to a state fund prior to the implementation of eMARS.

Grant accountants’ diligence to this effort will be measurable by the proportion of Federal Fund cash that is identified with eMARS’ program structures (i.e., grants or pseudo-grants).