A Really Cool Blog

… about science & space, people & politics, various musings & other cool things too.

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The Evolving Global S&E “Landscape”

The global science and engineering (S&E) “landscape” has experienced major shifts and evolution over time; the effect of different growth rates in S&E investment and different areas of S&E concentration across the globe has led to: the “catching up” in particular indicators of S&E activity in parts of the developing world, and S&E specialization in developed nations. As a result, a “multipolar world” for S&E has emerged after decades of preeminence by the developed world. S&E capabilities, until recently located mainly in the United States, Western Europe, and Japan, have spread to the developing world, notably to China and other Asian economies that are heavily investing to build their science and technology capabilities.

Multiple models and theories exist for this evolution, constituting the “convergence hypothesis.” Some countries appear to be converging with the leading economies, while others appear to be diverging with them. So long as trailing economies have much to learn from a leading economy’s performance, they will continue to catch up and approach the leader’s performance. However, as the distance between these economies narrows, the amount of unabsorbed knowledge and new technique to be applied begins to diminish, or even exhaust. The catch-up process begins to weaken or terminates unless some unrelated influence comes into play.

However, there are countries that are so far behind the leading economy that it is impractical to profit substantially from emulating the leading economy’s factors of productivity or absorbing their technology. They therefore fall behind, widening the gap between their economic performance even further. Some argue that a country’s ability to converge is a function of capital accumulation, technological innovation, and entrepreneurship which borrows ideas from abroad and adapts them to local circumstances. Others, however, highlight the important role of effective institutions, including incentives and markets, in determining which countries can economically and technologically converge with more advanced economies.

Looking at resources such as the OECD Science, Technology, and Industry Scoreboard; the UNCTAD World Investment Report; and the National Science Board’s Science and Engineering Indicators; the convergence and divergence of the global S&E landscape can be seen in R&D investment, research output, and global investment across sectors.

All three conclude that developing countries, particularly China, are experiencing robust growth trends compared to the United States and the rest of the developed economies of the world.

Over the last decade, almost all OECD countries saw increases in R&D investment and expenditure. There is also substantial heterogeneity in the share of “research” compared to “experimental development.” However, global R&D performance continues to remain concentrated in three geographic regions: North America, Europe, and the regions of East/Southeast and South Asia. North America accounted for 28% of worldwide R&D performance in 2015; Europe, including the European Union (EU) accounted for 22%; the combination of the regions of East/Southeast and South Asia (including China, Japan, South Korea, India, and Taiwan) accounted for 40%. The remaining 10% of global R&D comes from the regions of the Middle East, South America, Central Asia, Australia and Oceania, Africa, and Central America and the Caribbean.

In terms of research output, the United States, the EU, and the developed world produce the majority of refereed S&E publications. However, similar to the trends for R&D spending, S&E research output in recent years has grown more rapidly in China and other developing countries when compared with the output of the United States and other developed countries. China’s S&E publication output rose nearly fivefold since 2003. As such, China’s output, in terms of absolute quantity, is now comparable to that of the United States. Research output has also grown rapidly in other developing countries—particularly, Brazil and India.

Finally, looking at global investment, developing economies as a group are expected to gain about 10% of global foreign investment. This includes a sizeable increase in developing Asia, where an improved outlook in major economies is likely to boost investor confidence. Foreign investment into Africa is also expected to increase, with a modest projected rise in oil prices and advances in regional integration. Flows to transition economies are likely to recover further after their economies bottomed out in 2016. Flows to developed economies are expected to hold steady in 2017. In the last year, flows to transition economies almost doubled, to $68 billion, following two years of steep decline – reflecting large privatization deals and increased investment in mining exploration activities.

As can be seen by the statistics and metrics above, the developing world is largely converging with developed economies, and certain developing countries are rapidly increasing their research investments and research output. However, certain regions of the world, particularly those characterized by strong developed economies, continue to lead in research and development. Nonetheless, the rise of developing and transitioning economies in the ranks of research investment, research output, and as locations of investment indicates that the world is becoming “multipolar” for S&E as opposed to as it was traditionally, where a small subset of countries by far dominated the global science and engineering landscape.

Painting: Winter Mountains

“Winter Mountains

A Guide to Space Shuttles: How They’re Made and What Keeps Them Safe in Space

Article kindly provided by Casey Heigl (casey@heigltech.com).


Introduction


Since 1981, the space shuttle has hauled more cargo, carried more passengers, and traveled practically as many miles as all other U.S. manned spacecraft’s combined. Astoundingly, it’s now been almost 50 years since President Nixon signed off on the development of the space shuttle. Since that time, the shuttle has offered the most ambitious method of transporting humans into space in over five thousand years of effort.

Although most of us are familiar with the spectacle of manned space flight, those who are younger among us may not be. At the moment of liftoff, the shuttle both created and harnessed about 6.5 million pounds of raw thrust. Its three main engines, tiny in comparison to the unleashed power of twin solid-rocket boosters, generated the equivalent output of the Hoover Dam 23 times over.

Departing the launch pad, the space shuttle was all rocket. When it cleared the tower at a relatively slow 100 miles per hour, the shuttle was a study in thunderous vibration that grew in intensity over the initial few minutes of flight until the tail-off and drop of the solid rocket boosters.


Shuttle Safety in Space


 

Those who designed the shuttle envisioned a rough and tumble four-wheel-drive type of spacecraft that can handle the rugged back roads of space. It would come equipped with a standard array of overtly redundant systems—as many as four deep, in some cases—to heartily defend against any possible hardware or software problems. The systems onboard were meant to be nimble enough to return the crew home safely even if up to three levels failed.

The space shuttle’s thermal protection system or TPS was comprised of thousands of thermal tiles that served as a barrier to protect the vehicle during the scalding 3,000-degree heat of reentry into the Earth’s atmosphere. The TPS also protected the vehicle from the extreme cold and heat of outer space while in orbit.

The shuttle, in contrast with other vehicles, such as the Apollo, was designed to stay perfectly balanced on its own wings for the duration of the long, steep return to Earth. This balance was achieved through pure force. Scientists knew there were no aerodynamic forces on the shuttle above Mach 10. However, the real problem existed between Machs 8 and 1.

Scientists even broke down the Mach numbers into tenths, throwing all of the possible parameters back into a hopper, running and rerunning scenarios over and over until they could run a thousand times or more without a problem. If there was a single failure, they went back and made corrections to the system until 1,000 runs without failure were achieved for every possible Mach number.

Engineers used 50 or more wind tunnels of various speeds to shape and hone the vehicle since theory alone could not possibly account for every complexity of a typical shuttle flight.

Over time, the design of the shuttle accumulated over 100,000 hours of time in wind tunnels, which amounted to four times the testing of both the Boeing 757 and Boeing 767 developmental programs.


Tiles


The Challenger disaster came about in part due to a weakness in the tiles used to guard against the extreme heat of reentry. Later space shuttles used tiles made of ceramic fibers and a special silicone glue that bonded the tiles directly to the aluminum frame of the shuttle.


Plans Versus Budget Cuts


What the creators failed to realize, however, was that politics affects technology, which affects budgets. In practical terms, it meant there was a spending cap, and, to stay under that cap, compromises in the shuttle’s performance had to be made. Over the subsequent ten years, those budget cuts resulted in a painful hit to the program. Although painful, the compromises seemed somewhat reasonable at the time.

Although it might seem unheard of today, it’s interesting to consider even some of the elements that were included on the list of items NASA planned to include with their proposed 60 shuttle flights per year. The list included seven shuttles, three dedicated launch pads, a space station, and a fleet of “space tugboats” to pluck and place satellites in and out of Earth orbit. For some reason, not one of those “wish list” items was totally fulfilled, yet there was no change in the performance expectations of the shuttle program.


It’s a Go for Launch


In spite of all they had to go through, work on the space shuttle program continued and, eventually, the fleet began flying. Other than a couple of catastrophic events, the shuttle went on to become one of NASA’s most reliable vehicles for space launch and exploration. Indeed, its success-to-failure ratio indicated a much higher reliability than any other launch vehicle in the United States among space launch vehicles that have been in operation for more than 30 years. In comparison, Europe’s Ariane booster rocket had five failures within its initial 40 flights.

In its first ten years of operation, the space shuttle flew every week, yet it managed to launch nearly half of the entire mass of everything the United States has ever deployed into space.


The Space Shuttle Legacy


There are still other ways in which the space shuttle has stood the test of time. Its seemingly retro 1970s design template is still standard and state-of-the-art in many areas, including airframe design, automated flight control, thermal protection systems, electrical power systems, and the main propulsion system. The space shuttle’s main engines proved to be the world’s best chemical rockets, and they remain the only ones to date that can actually be throttled.

The space shuttle’s flight software is among the most advanced aerospace code on Earth, even years after the shuttle’s been retired. The space shuttle was also the only space vehicle that offered any kind of practical capability to return space cargo back to Earth. Additionally, it remains the only human-carrying vehicle type to be emulated by all other major space-faring nations.


The Future of NASA Space Travel


Who knows how history will ultimately judge the space shuttle? When the speed of sound was first broken, it was done with a research airplane. After flying a dozen times, the plane was discarded, donated to a museum, and work was initiated to create the next model with intelligence gained from that experience. The space shuttle did a tremendous job of serving both as a launch vehicle and a spacecraft which was capable of remaining in space for days or even weeks at a time. Perhaps the next generation of manned space vehicles will improve upon some of the space shuttle’s shortcomings. We are all still learning.

For the early American astronauts who pioneered high-speed flight, who worked on missions like the Apollo, and who helped turn that experience into the space shuttle, this was their goal all along.

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