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Right whales fart

Posted date: 6:54 PM / comment : 0 , , ,

You'll probably hear the parrotfish before you see them. The animals chomp through solid rock and coral with fused beaks. When you're snorkeling on one of Hawaii's reefs, the noise is unmistakable. Crunch, crunch, crunch.
To watch the grazers at work, it would be easy to mistake parrotfish for the bad guys. Their chompers scar the reef with deep gouges and reduce what was once hard stone into nothing more than a cloud of sand, squirted unceremoniously out the fish's backsides.
Yes, that is what happens.

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There are seven quintillion, five hundred quadrillion grains of sand in the world, according to math geniuses at the University of Hawaii. That’s more sand granules in Earth’s seas, lakes, and deserts than we could ever imagine.
Where does it all come from? In Hawaii, where beaches are constantly ranked the best in the world, a significant portion of that pristine, white, beautiful sand is actually poop.
Yep, poop.
Parrotfishes, or uhu in Hawaiian, are key players in regulating algae and reef life. Their parrot-like beaks and fused-together teeth are used for scraping and biting dead coral, while additional teeth in their throats help to break it all down into sand. Snorkelers can actually hear them chomping or see the bite marks they leave on rocks.
Because parrotfishes don’t have stomachs, their meals pass straight through the long intestine, exploding in a cloud of sand out the backdoor. Larger parrotfish are like sand factories, producing as much as 700 pounds of sand per year. For Oahu’s snorkeling hot spot, Hanauma Bay (where a few hundred parrotfish graze), that means hundreds of tons of fish-made sand per year.
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Worms, sponges, and oysters also produce Pacific ocean sand, but no animal is as proficient as the parrotfish, a badge of honor it has held for centuries. According to the Maui Ocean Center, the native Hawaiian name for the female redlip parrotfish translates to “loose bowels.”
But according to Darla White, a marine scientist with Hawaii's Division of Aquatic Resources (DAR), parrotfish are actually integral to both the reefs' day-to-day health and long-term resiliency.
"It's all about real estate on the reef," says White. "Every living thing is just looking for space, and each bite the parrotfish takes opens up an opportunity for coral larvae to settle in."
Those bites are more valuable now than ever. Coral reefs thrive on clean, clear, low-nutrient water. But runoff from the islands contains fertilizers from farms and lawn care, and these excess nutrients cause both naturally occurring and invasive algae to go haywire. Before you know it, all the available real estate is shellacked with fast-growing algae, and the extremely slow-growing coral can't colonize these surfaces. Parrotfish keep these blooms in check by beak-biting straight down to the substrate.
(Jeffrey L. Rotman/Corbis)
Unfortunately for the reefs, parrotfish are freaking delicious. They are also beautiful. And that means the fish are a prized target of both subsistence-, sport-, and even some commercial-fisherman. Most herbivores don't take a hook, but spearfishing and nets work well enough. Add to this the unfortunate fact that many species of parrotfish are also really heavy sleepers, and you can see there's a problem. At night, they secrete a layer of mucous across their body that's thought to protect them from parasites and perhaps keep predators from sniffing them out. But it does nothing to prevent unscrupulous night divers from plucking the fishies from the reef like cooling pies off the proverbial windowsill.
To combat these pressures, White and her colleagues at the DAR designated part of the reef along West Maui's coast as the Kahekili Herbivore Fisheries Management Area in 2009. This made it illegal to kill or injure several species of herbivorous fish, including parrotfish, surgeonfish, and sea chubs, as well as sea urchins anywhere in the preserve. After several years of watching and waiting, they analyzed the results in 2012 and reported that parrotfish biomass had actually doubled. What's more, they found a strong positive relationship between total parrotfish biomass and the amount of coral growing on the reef.
Problem is, White says only 1 percent of Hawaii's coral reefs are under this kind of protection — which means most of the region's parrotfish are getting picked off before they can even reach full size. And this is a problem, because when it comes to parrotfish reproduction, size matters.
Hawaii's parrotfish live in harems — one guy to half a dozen or more gals — but every fish begins its life as a female. If the harem's male gets speared by a diver or otherwise decides to go out for a pack of smokes, the most dominant female can, over time, turn herself into a male.
You can tell when a female is going through this miraculous transformation because she will start to change from a dull gray to the more striking blues, greens, and purples of parrotfish males. And because the change doesn't just simply happen overnight, it's not uncommon to see a parrotfish swimming around that's half gray (female) and half green (male).
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Before the color change is complete, some species of parrotfish use their half-and-half status as camouflage, deftly sneaking into harems that still have a super-male and fertilizing the females' eggs before the alpha fish knows what's up. (Note: This is known as "streaking" (through the Quad), and it's a good way to get your ass beat. Parrotfish are highly territorial.)
It should come as no surprise then that the biggest, beefiest, most flamboyantly colored parrotfish — which you now know to be exclusively male — are at the highest risk of human predation. This makes repopulating the reefs with algae-eaters all the more difficult, since males aren't simply hatched — they're built, over time and circumstance.
"It's human nature to try to fix something once it's broken," says White, regarding the state of Hawaii's reefs. "But to try to fix an entire ecosystem, especially one that's in the water? It's not easy."
But that won't stop them from trying. The DAR has partnered up with organizations like the Coral Reef Alliance and local businesses like The Snorkel Store to educate policymakers and actually get them in the water to see what's at stake. They've worked with hotels and landscapers to raise awareness about runoff. And the Coral Reef Alliance established something called the Fish-Friendly Business Alliance, which promotes businesses that don't sell fish food — because if grazers are eating pellets out of the hands of tourists, they don't have to eat as much algae.
Whether it's reducing algae and pollution or giving parrotfish populations a chance to rebound, the goal is to return Hawaii's reefs back to some semblance of balance — or lokahi, as the locals might say. Here on the mainland, I think that translates to, "You break it, you bought it."

References:

Asus unveils 5-in-1 Android/Windows Transformer Book V tabfonetop

Posted date: 1:19 PM / comment : 1 , , ,

Asus Transformer Book V: A Windows, Android, laptop, tablet, and smartphone five-in-one!
If you thought that Microsoft’s tablet-that-turns-into-a-laptop was cool, the Asus Transformer Book V — unveiled at Computex 2014 in Taiwan — will blow your mind. Like previous 2-in-1 Transformer Books, there’s a Windows tablet that clicks into a laptop base — but now there’s also a slot on the back of the tablet for an Android smartphone! All told, this hideous three-in-one device has five modes of operation: a Windows laptop, a Windows tablet, an Android smartphone, an Android tablet, and an Android laptop. There’s no word on pricing or release date.
Okay, let’s break this beast down. First, the main brain of the operation is the tablet: a 12.5-inch device running Windows 8.1, with an Intel Core CPU under the hood, 4GB of RAM, a 28 watt-hour battery, and up to 128GB of flash storage. Reports seem to differ on the resolution of the screen (some say 1920×1080, some say 1366×768). In the laptop keyboard/base station, there’s a 1TB hard drive — and that’s about it (not quite as fancy as last year’s Transformer Book Trio, which had a full PC in the base). On the back of the tablet there’s a slot that will take a 5-inch, ZenFone-like smartphone. The smartphone will apparently be the first device in the world with Intel’s 64-bit Moorefield (Atom) SoC.
Asus Transformer Book V
Asus Transformer Book V. You can see the Android home screen running in a window in the background. [Image credit: Engadget]
The various parts of the Asus Transformer Book V (pronounced “five”) interact in the following ways. The tablet can be used as a Windows tablet, or as a Windows laptop. The smartphone can obviously be used as a normal Android smartphone. When you slot the smartphone into the tablet, you then gain the ability to run Android apps on your Windows desktop — or you can let Android take over the display entirely, turning the device into an Android tablet (or laptop, if you’re docked). The tablet gains LTE connectivity when the smartphone is plugged in. There will be some interchange of data between the two devices, but the exact implementation isn’t clear.
In terms of real-world usefulness, color us fairly skeptical. If the tablet part features an Intel Core processor, expect the entire Transformer Book V package to be very expensive — probably in the $1500 to $2000 range. While we don’t have the tablet’s exact weight, it will probably be in the region of 700-800 grams — which will be rather heavy, once you plug in the 140-gram smartphone. While there’s something to be said for a very cheap, “dumb” tablet that merely extends the size of your smartphone’s screen, I think putting a smartphone slot in the back of a full-featured 2-in-1 tablet/laptop is probably taking things a bit too far.
The various modes of the Asus Transformer Book V
The various modes of the Asus Transformer Book V
Having said that, if you’re in the market for a new smartphone, and potentially a new tablet as well, there’s no real reason why you shouldn’t at least try the Asus Transformer Book V. When you actually have all three parts laying around, and assuming the interchange of data between Android and Windows isn’t too clunky, some fairly useful scenarios might actually emerge.
I think the whole setup would be cheaper and more interesting if there was only one processor, though, in the smartphone. Then you could walk around with the smartphone, and turn it into a tablet or laptop if you want to consume some media or do something productive. That would be pretty close to my vision of the future, where the smartphone isthe PC of the future.

Regenerating plastic grows back after damage

Posted date: 9:47 PM / comment : 0 ,

Regenerating plastic grows back after damage

Regenerating plastic grows back after damage
(Photo : Ryan Gergely) Illinois researchers have developed materials that not only heal, but regenerate. The restorative material is delivered through two, isolated fluid streams (dyed red and blue). The liquid immediately gels and later hardens, resulting in recovery of the entire damaged region. This image is halfway through the restoration process.
Looking at a smooth sheet of plastic in one University of Illinois laboratory, no one would guess that an impact had recently blasted a hole through it.
Illinois researchers have developed materials that not only heal, but regenerate. Until now, self-repairing materials could only bond tiny microscopic cracks. The new regenerating materials fill in large cracks and holes by regrowing material.Led by professor Scott White, the research team comprises professors Jeffry S. Moore and Nancy Sottos and graduate students Brett Krull, Windy Santa Cruz and Ryan Gergely. They report their work in the May 9 issue of the journal Science.

"We have demonstrated repair of a nonliving, synthetic materials system in a way that is reminiscent of repair-by-regrowth as seen in some living systems," said Moore, a professor of chemistry.

Such self-repair capabilities would be a boon not only for commercial
goods - imagine a mangled car bumper that repairs itself within minutes of an accident - but also for parts and products that are difficult to replace or repair, such as those used in aerospace applications.

The regenerating capabilities build on the team's previous work in developing vascular materials. Using specially formulated fibers that disintegrate, the researchers can create materials with networks of capillaries inspired by biological circulatory systems.

"Vascular delivery lets us deliver a large volume of healing agents - which, in turn, enables restoration of large damage zones," said Sottos, a professor of materials science and engineering. "The vascular approach also enables multiple restorations if the material is damaged more than once."

For regenerating materials, two adjoining, parallel capillaries are filled with regenerative chemicals that flow out when damage occurs. The two liquids mix to form a gel, which spans the gap caused by damage, filling in cracks and holes. Then the gel hardens into a strong polymer, restoring the plastic's mechanical strength.

"We have to battle a lot of extrinsic factors for regeneration, including gravity," said study leader White, a professor of aerospace engineering. "The reactive liquids we use form a gel fairly quickly, so that as it's released it starts to harden immediately. If it didn't, the liquids would just pour out of the damaged area and you'd essentially bleed out. Because it forms a gel, it supports and retains the fluids. Since it's not a structural material yet, we can continue the regrowth process by pumping more fluid into the hole."

The team demonstrated their regenerating system on the two biggest classes of commercial plastics: thermoplastics and thermosets. The researchers can tune the chemical reactions to control the speed of the gel formation or the speed of the hardening, depending on the kind of damage. For example, a bullet impact might cause a radiating series of cracks as well as a central hole, so the gel reaction could be slowed to allow the chemicals to seep into the cracks before hardening.

The researchers envision commercial plastics and polymers with vascular networks filled with regenerative agents ready to be deployed whenever damage occurs, much like biological healing. Their previous work established ease of manufacturing, so now they are working to optimize the regenerative chemical systems for different types of materials.

"For the first time, we've shown that you can regenerate lost material in a structural polymer. That's the kicker here," White said, "Prior to this work, if you cut off a piece of material, it's gone. Now we've shown that the material can actually regrow."

10 GIFs Of Deep-Sea Creatures Encountering A Sub

Posted date: 7:06 PM / comment : 0

10 GIFs Of Deep-Sea Creatures Encountering A Sub

Never-before-seen images from a recent expedition to the ocean floor

For the past three weeks, we've been following an incredible livestream of the bottom of the Gulf of Mexico, filmed from a submersible operated by researchers aboard the Okeanos Explorer. The expedition, led by the National Oceanic and Atmospheric Administration, ended this week. Using the sub's high-def camera, the scientists captured footage of parts of the ocean floor never before seen by humans, including ancient shipwrecks, unidentified species, and rare geology.
We'll have much more coverage of this expedition next week, so stay tuned. But in the meantime, enjoy these animated GIFs of deep-ocean creatures that wound up in the sub's LED beams—many of them likely experiencing bright light for the first time.
Note: To avoid crashing anyone's browser (or our servers) we've split these 10 GIFs over four pages. Choose single-page view at your own risk.
This is a dumbo octopus using its ear-like fins to swim. According to NOAA, this coiled-tentacle posture has never before been witnessed in this species.

Here's another view of the same dumbo octopus.

This was an exciting moment. A bright red creature—a Humboldt squid?—swam right past the sub's cameras before disappearing into the darkness.

Here's a gorgeous sea cucumber.

A rat tail fish suddenly realizes it has an audience.

A jellyfish swims in a current.

Hello, fish. Behold human technology.

A little red shrimp swims away from the sub.

At first, the researchers couldn't tell what this creature was, only that it was rapidly fleeing the ROV. Turns out to have been some kind of ray or skate.

Here, oil naturally bubbles up from the ocean floor amid sea urchins and mussels.

The Average Women Faces In Different Countries

Posted date: 10:47 PM / comment : 0

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International Team Develops Real-time Structural Sensors

Posted date: 9:29 PM / comment : 0 ,

International Team Develops Real-time Structural Sensors
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Cracks in critical steel and concrete structural members
Cracks in critical steel and concrete structural members could be detected far earlier using nanotechnology-based, real-time sensors that are being developed and tested in Iowa and Italy. Wikimedia Commons/Achim Hering
Teams in Iowa and Italy collaborate to develop two different sensor technologies that will enable real time monitoring of large, complex structures.

April 1, 2014—Researchers in Ames, Iowa, and Perugia, Italy, are working collaboratively on separate nanocomposite materials technologies to measure the performance of large structures in real time and alert authorities to changes brought on by strain. The technology has the potential to provide alerts about such critical structural changes as cracks months or even years before they might have been discovered by visual inspections.

At Iowa State University, a team led by Simon Laflamme, Ph.D., A.M.ASCE, an assistant professor of civil, construction, and environmental engineering, is developing a soft elastomeric capacitor (SEC) system—a surface covering that mimics human skin’s sensing capability.

At the University of Perugia, a team led by assistant professor Filippo Ubertini, Ph.D., is developing a carbon nanotube, cement-based sensor (CNTCS). The carbon nanotubes are embedded in cement paste, either during casting or later by mortar application. Ubertini is currently focused on adding nanotubes to historical structures to monitor any changes following such extreme events as earthquakes.

“In both cases, they are similar in a sense that strain would provoke a change in geometry in the material,” Laflamme explains. “For the CNTCS, it’s a strain in the cement paste itself. Strain provokes a change in geometry, and a change in geometry provokes a change in [the] conductivity of the material.” The system can be likened to a resistor; the electrical resistance of the cement paste changes based on the geometry of the strain.

“The SEC is similar, except a change in geometry on the skin will provoke a change in the capacitance,” Laflamme says. “We have two different pieces of electronics here. One is a resistor, the other is a capacitor.”

Both research teams are focusing on deploying their technology on a large scale. Laflamme notes that currently available technologies are either not economically feasible for large-scale applications or provide a data stream that is too complex to quickly analyze and distill into actionable information.

“We want to be able to deploy our technology on very large surfaces. Think of any civil infrastructure, or even mechanical systems,” says Laflamme, who is currently working with both the wind turbine industry and the Iowa Department of Transportation (DOT) to develop specific applications of his SEC.

“With our technology, we are trying to develop sensing solutions around an application,” Laflamme says. “An example of that is the project we have funded by the Iowa DOT. They would like to deploy the skin on key areas of a steel bridge. A skin would be able to detect and localize fatigue cracks. Fatigue cracks are very important to any DOT.” The SEC would also be able to provide the location and size of any cracks detected.

“It really beats visual inspections,” Laflamme notes, because visual inspections are conducted only a specific schedule, and fatigue cracks can appear any time—even soon after an inspection—and grow worse over time.

In the summer of 2013, researchers from the two schools met in Italy for a test of the two technologies utilizing a concrete beam. The tests revealed that both technological approaches work well in what Laflamme terms a basic test. Perhaps more importantly, the collaboration allowed each team to combine their strengths in different areas to advance the work of both.

“Our experience was quite complementary,” Laflamme says. “We were both able to advance our solutions to the next level by discussing and giving feedback on what is happening with each other’s technologies. It was phenomenal. When you do these exchanges, you have the opportunity to really focus for the time you are there. We were there for a full week of brainstorming, discussions, tests, and data analysis.”

The team recently published the paper “Novel Nanocomposite Technologies for Dynamic Monitoring of Structures: a Comparison between Cement-Based Embeddable and Soft Elastomeric Surface Sensors” in the journal Smart Materials and Structures. Other papers are being developed, and the two teams plan to continue their collaboration. The next steps in the development of the technologies are to test for the ability to localize damages, develop a large-scale test project, and formulate a method to quantify the cost savings that the technology might offer to infrastructure stakeholders.

“How do your prove that a sensing technology will make you save money by increasing the lifecycle of the structure? To me it’s intuitive. [But] if someone asks for data, we don’t have much,” Laflamme says. “So there is some work to be done in demonstrating that there is an important rate of return on investment for sensing solutions.”

The Rise and Demise of Egypt’s Largest Pyramids

Posted date: 9:28 PM / comment : 0 ,

My love of Egypt and my first contact with Egyptian construction started in 1994 when I was asked to provide a scheme to strengthen parts of historic Cairo after the devastating earthquake in 1992. This initial contract was to work with the state-owned Arab Contractors to strengthen the Al Ghory Mosque, which had been extensively damaged. It was at that time that I was able to visit the Giza Plateau to see the pyramids.

My first view of the Great Pyramid was in the early evening when I got out of my vehicle at a local hotel. I was expecting to see a pyramid, but I was not prepared for the scale and size of the monument that was in deep shadow at that time of the day, almost obliterating half the sky. Like many other visitors, the first question that inevitably came to my mind was: ‘How could people with primitive tools build these fantastic monuments in such a short time?’ At that time, I did not take any professional interest in the construction of the pyramids, but I did feel a great deal of respect for the constructors.

Although we have been fascinated with how the ancient Egyptians built these incredible monuments, there is still a lot of discussion and mystery surrounding the actual method. The Step Pyramid of Djoser, which is 62 meters (203 feet) high, was the first high-rise structure that the ancient Egyptians built; previously, their structures were no more than 10 meters (33 feet) tall. How did the ancient Egyptians manage to construct the Step Pyramid, having never before erected a structure anywhere near that size?

Figure 1. The burial chamber of the Step Pyramid.
My professional interest in the construction of the pyramids was initially sparked by observations that I made during Cintec’s work restoring the ceiling of the burial chamber of the Step Pyramid. We were called in to restore the ceiling, which was collapsing due to the failure of the timber beam that the ancient Egyptians had used to hold the ceiling stones in place (Figure 1). Our unique Waterwall airbags supported the dangerous hanging stones temporarily, and our patented anchors permanently secured them (Figure 2).

Figure 2. Cintec Waterwall airbags supporting ceiling of Step Pyramid.
While in the burial chamber, I noticed that although we were drilling holes that were 4 meters (13 feet) in length, we never actually drilled through stones that were more than 40 centimeters (16 inches) wide. This appeared to be a direct contradiction of the common belief that the enormous stones on the outside were the same all the way through the pyramid. In some cases, the fill was a great deal smaller. It was this observation that prompted me to question the accepted theories that attempt to explain how the pyramids were built. Having worked in the construction industry for 54 years, I began to analyze these theories from a practical builder’s perspective.

I put myself in the mind of an ancient Egyptian builder faced with limited tools and little experience of large-scale construction. The main problem that I found with the existing theories was that, from a builder’s perspective, they made the process more difficult than it needed to be. Why would the Egyptians haul huge stones from a long distance away unless it was absolutely necessary? The internal core and filling would never be seen, so why fill it with quarried blocks that took time and presumably money to extract and transport to the site? The logistical problems were already enormous -- coordinating all the elements from quarrying, transport, scaffolding, design, setting out and manpower requirements.


A Progression of Knowledge


Cintec has undertaken restoration work in both the Red and Step Pyramids in Egypt, and during this work I have observed the progression of the ancient Egyptians’ knowledge of construction techniques. With every pyramid they built, they became more skilled and corrected previous design defects. One such example is their use of corbelling to create openings in the pyramid for the burial chamber.

At the Step Pyramid, the builders attempted to create an opening for the chamber by using large timber beams. However, the timber buckled and failed, causing stones to fall. It was this failure that Cintec was brought in to correct. When the ancient Egyptians moved on to create the burial chamber ceiling in the next two pyramids, the Meidum and Bent Pyramids, they attempted to use a corbelling technique to overcome the failure of the timber beams. Both of these pyramids have unusual shapes; the Bent Pyramid’s top section sits at a slightly different angle to the main body, giving the structure its ‘bent’ appearance, while the Meidum Pyramid has the appearance of a truncated box sticking out of the ground, rather than the even slopes of the later pyramids.

Corbelling stone and masonry is now a well-known technique in construction. However, the ancient Egyptians were newly using it when building the pyramids. Therefore in both the Meidum and Bent Pyramids, the builders exceeded the overhang needed for the corbel arch to support the weight. This resulted in the burial chamber being squeezed together, and it is this mistake which I believe is the cause of both pyramids’ unusual shapes. The builders rectified it in the construction of the next pyramid, the Red (or North) Pyramid, which is a perfect example of the correct use of corbelling and has a true pyramid shape.


How Were the Pyramids Actually Built?


This progression of knowledge shows that the ancient Egyptian builders were pragmatists, and as such would have always built in the simplest and most efficient way they knew how. As stated earlier, I have found many of the existing theories on how the pyramids were built to be overly complicated and sometimes entirely impractical. I believe that they instead employed much simpler and therefore more viable methods than many current theories propose. It is my opinion that the pyramids were constructed using internal ramps, combined with some additional scaffolding, and not with enormous external ramps, a theory currently favored by many archaeologists.

I believe that the pyramids consist of three different layers (Figure 3). First is the middle core that is visible on every pyramid after the Bent Pyramid. I predict that this layer is only three blocks wide, with the blocks diminishing in size as they near the apex. This layer was used by the Egyptian builders to retain the core filling and would have been a key to connect the outer cladding. The step design of the pyramid meant that the builders were able to connect the cladding to the pyramid while still supporting the weight of the cladding blocks.

Figure 3. Diagram demonstrating the three layers of the pyramid.
From my observations of the burial chamber of the Step Pyramid, I believe that the infill and central core of the pyramid primarily consist of much smaller stones, and any other larger blocks that the builders wanted to conceal. The inner core was used to create internal ramps, which enabled the Egyptians to build the pyramid from the inside out (Figures 4 and 5). The ramps were started at the mid-point of the pyramid and would zigzag across its full internal width, matching the height of the middle-core stones as the pyramid was built. The small number of heavy middle core blocks could have been raised on these internal ramps and positioned at the perimeter of the pyramid. As most of the inner fill stones were much smaller, they could have been easily handled by men and animals.

Figure 4. Stylized diagram of the first stage of construction.
Figure 5. Stylized diagram of the second stage of construction.
The ramps would get steeper as the pyramid grew in height, but they would not exceed the normal angle used to calculate the external ramp gradient. The ramps could have had small palm tree trunks partly embedded into them as a mechanism to slide the heavier core blocks on wooden sledges. As the pyramid reached the apex, more reliance on scaffolding would have been necessary to top out the structure.

The final layer is the outer cladding, which would have been added last and used by the ancient Egyptians to smooth the outer appearance of the pyramid and ensure its ‘true’ pyramid shape using additional stones or tufla grout, like the final icing on a cake.

Some people have been skeptical of any theory involving the use of scaffolding, as they argue that the ancient Egyptians would not have had access to enough timber. My method requires only a small amount of scaffolding in order to attach the outer cladding, and the same scaffolding could have been moved around the pyramid as they worked. In recent restoration work on the pyramids, traditional timber lashed together has been used as scaffolding (Figure 6), which demonstrates that it clearly would have been possible to use scaffolding to construct them in the first place.

Figure 6. Scaffolding in use on the Step Pyramid.

Conclusions


I acknowledge that these are only my theories and not facts. However, there is a way to prove my theory of the layers of the pyramid, and I volunteer to carry out this work at no charge to the Egyptian Antiquities. We could diamond drill 100-millimeter (4-inch) core holes into the pyramid at varying heights to a depth of 30 meters (100 feet) and provide a drilling log of all the contents of the bored hole to establish the true nature of the fill. The drilling would be done with the latest dry drilling techniques to prevent damage to the pyramid, and the core would be plugged and filled to match the external appearance.

The short period of intensive construction by an ancient civilization who managed to build these wonderful monuments was remarkable. One can only admire the great ingenuity and effort that was required by a team of specialist builders, who from the very start showed great ingenuity and the ability to adapt, overcome problems, and learn from their mistakes.▪

Peter James (peterjames@cintec.co.uk), is the Managing Director of Cintec International in Newport, South Wales, United Kingdom. He has worked on projects across the globe, strengthening and restoring historically significant structures from Windsor Castle to the parliament buildings in Canada.
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Why Are Roofing Materials Corrugated or Ribbed?

Posted date: 11:37 PM / comment : 2 , ,

Strength

  • The corrugations in roofing materials are created by a process known as roll-forming, which creates a material that is stronger and more rigid than a flat sheet of the same thickness. Corrugated metal roofing, in particular, has a high strength of material to weight ratio.

Protection

  • Provided the pitch, or slope, of a corrugated roof is sufficient, the corrugations provide more effective channeling for the runoff of rainwater than a plain roof. There is a minimum pitch for corrugated sheeting, often around 5 degrees, but this is much lower than the requirement for other roofing materials, such as tiles.

Weight

  • Corrugated roofing materials are relatively lightweight and easy to handle when compared with other roofing materials. This means that they provide a cheaper, more convenient method of roofing and reduce the weight of material above your head; this can be a consideration if you live in an area prone to earth tremors.
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