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Look, I should be clear—I didn’t want anything to do with “the dread lord,” or whoever Januk was talking about. I was just trying to sell this stupid little vial to the guy who asked me to get it for him. Should have been easy.
But when you’re me, nothing goes your way for long.
My way. Whatever.
Januk was a red-bearded Freljordian transplant, with deep pockets and big appetites. Unknown to his employers, his private residence was filled with relics and artwork, half of it raided illegally from tombs or other museums, and he loved to dine amidst his collection. As some of the pieces would attest, we’d worked together several times in the past, and he only betrayed me twice. Well, two and a half times, if I’m counting when he blew my cover after we had already salvaged the wreck of the Echelon Dawn…
To Januk’s credit, payment was never a problem, which vastly diminishes my ability to hold a grudge.
“Ezreal,” he said, pushing his plate aside. There were flecks of lamb in his teeth. “Did you find it?”
The it he was referring to was to the Elixir of Uloa. And yes, I had indeed liberated it from a trap-strewn hovel in the jungle near Paretha. I pulled the bone and crystal vial from my satchel. It was cool in the palm of my hand.
“Got what you’re looking for right here,” I said, holding up the vial. “Interesting container. My best guess would be pre-classical Shuriman.”
The spoonful of viscous liquid inside it shimmered in the moonlight. Januk’s eyes widened.
I decided to ramp up the drama. “I tell you what, though—this here isn’t just any ordinary ancient serum. It’s a load bearing ancient serum. The whole place crumbled around me. I barely escaped with my life.”
“The Elixir…” Januk’s voice took on a reverence I had never heard before. “A single drop can quench the soul for a thousand years… Give a man skin as tough as petricite…”
He went to grab it with his greedy hands. I pulled it out of reach.
“Not so fast, Januk.”
“Right, right, right,” he muttered, fumbling for his desk drawer key. “Payment. We agreed sixty thousand.”
“And full accreditation in the Guild, remember?”
I’d been denied entry to plenty of things, in my time. Bars, schools, even a Sona recital… but the Piltover Explorers Guild was the one that stung the most, considering the number of times I’ve risked my neck in the field. Ingrates.
Januk was scowling. “The Guild aren’t particularly fond of you, Ezreal. Can’t say I blame them, having worked with you in the past.” He poured himself some amberwine from a decanter and took a swig. “You left me to rot in that Noxian prison camp…”
“That was payback. For the Echelon Dawn.”
“Which was payback for the map.”
“Which was payback for… something else you did.” I gritted my teeth. “Probably.”
I was getting antsy. I readied myself to make a quick exit.
“Come on, accreditation was half the deal,” I reminded him. “If you don’t want to honor it, I can always find another buyer.”
His boisterous laugh broke the tension. “Why do you think I continue to do business with you? It’s because I like you. We have history, and history is always good for business.” He finished his drink. “Let me fetch the letter from my study. One moment, please.”
Buyers keeping payment in their studies? Oldest trick in the book. He’d probably return aiming a flintlock at my pretty face.
To kill time, I perused his collection of artifacts. There were some I had procured on his behalf. Then my eyes fell on something I had not seen before. Something new—a stone bell, roughly the size of a housecat. Its base was adorned with strange writing. I stepped closer to inspect it.
“It’s Ochnun,” Januk called out. “The language of the dead, composed beyond the mortal veil, and spoken only by those in the afterworld.”
I was getting some serious backstabby vibes, so I spun around.
Januk didn’t have a flintlock. He had two flintlocks.
“I am sorry to inform you, Ezreal, that the Guild has once again denied your application.” He stepped closer, into the light. “The dread lord will rise again. And the Elixir will make it happen.”
A dread lord? Great. I was so close this time…
My gauntlet’s charge rose. Anger is a wonderful arcane motivator. Use it or lose it, I always say.
I raised my arm. Januk fired his pistols. It was magic versus lead shot.
Surprise! Magic won. Magic always wins.
The dull metal slugs burned white-hot in the face of my blast, and winked into silvery vapor on the other side. But with double-crossers, one must be doubly careful, so I quickly charged my gauntlet again. There was a slight fizzle, then a pop, and then I was standing right behind Januk. Teleporting short distances doesn’t really take a lot out of me, so I put my gauntleted hand to the back of his big, stupid head before he could turn around.
“Drop the guns, Januk.”
“Already one step ahead of you.”
Oh, I did not like the sound of that. I glanced down. Sure enough, the pistols were at his feet.
Did I mention Januk was strong? Because he is super strong. He grabbed my gauntlet in one hand, yanked me over his shoulder with the other, and slammed me bodily through his work desk. The damn stone bell jabbed into my spine. I saw white, and splinters. Lots of little splinters.
Januk kicked me in the ribs for good measure. He twisted the Elixir of Uloa out of my shaky grip, pulled the stopper, and drank deep.
“Your pathetic gauntlet will do nothing to an immortal! The Elixir is—”
“Fake,” I croaked. “Almost the right hues, though.” I held up another, far less remarkable looking vial. “This is the real Elixir. You just drank sand wasp venom, out of a cheap souvenir trinket vessel.”
Januk peered into the empty vial, his face scrunched up like he’d tasted sour milk. In fairness, sour milk would have been a lot better for his digestive system.
I winced as pulled myself back to my feet. He had kicked me unnecessarily hard, but at least he spared my face.
“If I were you, I wouldn’t stray too far from a lavatory for the next few days,’ I added.
He threw the fancy casing to the ground, doubled over, and groaned. Sand wasp venom hits hard and fast. “You… petulant little… I’ll get you… for this…”
I shrugged, then raised my gauntlet and fired another blast of magical energy at the wall. The masonry cracked, melted and exploded outwards. Papers flew everywhere. I picked up the bell, and crouched by Januk’s new window.
“Always a pleasure, ” I said. “I won’t charge you for the, uhh… remodeling.”
I hopped out through the hole, scampered down the masonry and leapt across to a nearby rooftop. I wanted to be far away from Januk as quickly as possible, for lots of reasons. Admittedly, the sand wasp venom was the main one—it was not going to be pretty in that place by morning.
As I ran, I took a closer look at my latest acquisition. Whatever else it was, the Ochnun bell was definitely touched by some darker energy. Once the Explorers Guild got a load of this piece, I’d be a shoo-in for accreditation. With a party in my honor, perhaps? After all, I had just single-handedly kept some dread lord from rising.
And in the end, that’s usually all that matters.
------- EPA REVIEW NOTICE This report has been reviewed by the U.S. Environmental Protection Agency, and approved for publication. Approval does not signify thai the contents necessarily reflect the views and policy of the Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This document is available to the public through the National Technical Informa- tion Service, Springfield, Virginia 22161.
------- EXECUTIVE SUMMARY The RAETRAD (RAdon Emanation and TRAnsport into Dwellings) model has been developed to provide a simple, inexpensive means of estimating the rates of radon gas entry into dwellings from underlying soils. It can represent slab-on-grade houses of different sizes and shapes on soils with any distribution of radon source strengths, physical properties, water contents, and gas transport properties. It was developed in part under the Florida Radon Research Program (FRRP), which has been co-sponsored by the Florida Department of Community Affairs (DCA) and the U.S. Environmental Protection Agency (EPA). It has been used in the FRRP to characterize the effects of foundation soil and fill properties on indoor radon entry, to characterize the modes of radon entry, to characterize soil radon potentials for mapping of their geographic distributions, to develop simplified lumped-parameter models, and to support development of radon-protective building construction standards. RAETRAD computes radon production from radium decay, radon interactions in the solid, liquid, and gas phases of soils and concretes, and radon gas transport and indoor entry by both diffusion (concentration-driven) and advection (with pressure-driven air flow). It solves LaPlace's equation in steady state to define air pressure distributions under and near the house and to obtain air flow velocities that are used in the radon calculations. The radon differential equation also is solved in steady state, and incorporates the air velocity field in computing simultaneous diffusive and advective radon transport. The equations are solved numerically in elliptical-cylindrical geometry to represent houses of different sizes and with varying rectangular aspect (length/width) ratios. Radon entry rates into a house are computed by integrating the total radon transport across the floor surface area. Indoor radon concentrations also are estimated from the computed entry rates by dividing by the house volume and its air ventilation rate. Several analytical functions are used in RAETRAD to enhance its computational efficiency and to simplify its user interface. The numerical calculations of air flow and radon transport through floor cracks are accelerated by use of analytical functions to estimate the mesh-equivalent permeabilities and radon diffusion coefficients for the specified cracks rather than using finely-graded numerical meshes to represent them. Analytical functions also are used to define soil radon diffusion coefficients and air permeabilities for cases in which measured values are unavailable. These use soil porosities, water contents, and textures to define the radon transport properties from empirical correlations with measured data. In addition to modeling symmetric cracks in the floor slab, RAETRAD also accommodates asymmetric openings such as utility penetrations that do not match the elliptical symmetry computed for the equivalent rectangular house shape. These are represented by multiple numerical calculations that determine transverse leakage terms for the discrete-point floor openings. The numerical-analytical calculations are performed by computing all finite-difference coefficients for each model mesh unit and solving the equations simultaneously by a non-iterative matrix inversion technique. The resulting computer code is relatively small and efficient, and operates on an IBM"- compatible personal computer. Typical execution times are on the order of 1-2 minutes or longer, depending on the complexity of the problem being solved and the speed of the computer. A user interface provides queries for definition of an input file and selection of appropriate input parameters. i i i
------- The RAETRAD code was validated and benchmarked by several comparisons with analytical calculations and with empirical radon data. The analytical validations included comparison with a 2-dimensionaJ air pressure field calculated for a simple uniform 15 ft. x 31 ft. soil space with two different pressures applied at its top surface. Relative standard deviations of less than 1 % were obtained between the RAETRAD calculations and the analytical pressure field at the 1-, 2-, 4-, 8-, and 15-ft. depths below the pressure boundary. Analytical validations with 1-dimensional radon generation and diffusion from an open soil and a concrete-covered soil suggested the utility of defining a small (0.1-ft) mesh unit at the top of the soil profile to minimize the effects of mesh spacing. In these comparisons, both soil radon profiles and surface radon fluxes agreed consistently within less than 1%. Additional 1-dimensional validations included a uniform soil with radon generation, diffusion, and advective transport. In this case, the air flow velocities were forced by an external definition of a uniform pressure gradient, since RAETRAD is designed to compute only realistic, 2-dimensional pressure profiles. Again, agreement was within less than 1 % for all cases of air flowing into the soil profile. When air was drawn from the profile, a depletion of the profile was observed that caused a maximum error of 4% for the case that was analyzed. This error was reduced by considering a thicker soil profile, and was exaggerated if a thin soil layer was considered. Comparisons of RAETRAD calculations with empirical radon measurements utilized two test-cell structures (6 m x 6 m) constructed in South-Central Florida and monitored primarily by Southern Research Institute (SRI). One of these structures (test cell 1) utilized floating-slab floor construction with concrete-block stem walls over a concrete footing. The other structure had similar footings and stem walls, but its floor slab was poured to extend into a course of chair blocks at the top of the stem wall. Both cells had identical wood-frame superstructures, without windows, that were sealed with 2-3 cm of polyurethane foam to minimize air infiltration. Soil densities, radium concentrations, radon emanation coefficients, and moistures were measured in this project from numerous cores collected around and under the test cells. SRI provided measured soil radon and air permeabilities, and indoor pressures, air"ventilation, and radon concentrations. Field soil sampling at the test cell site extended only to 4-7 ft. depths for most cores; hence deeper soil regions were extrapolated from existing moisture and radium data. Calculated radon concentration profiles were within 4.4% of the means of measured values under test cell 1, compared to a 34% root-mean-square uncertainty among the measured values. Calculated radon profiles were within 18% of the means of measured values under test cell 2, compared to a 42% root-mean-square uncertainty among the measured values. Measured soil air permeabilities differed from values calculated from soil density, moisture and texture by 42%sbased on composite averages at four different depths. Excluding a heterogeneous, low-permeability layer under part of the site, the agreement was improved to 24% relative standard deviation. Indoor radon in the test cells was analyzed by RAETRAD to compare with measurements before and after drilling a center hole in each of their slabs. For the initial slab conditions, RAETRAD computed 97 pCi L"1 in test cell 1, only 2% above the mean of the measured values, 95 ± 44 pCi L'1. The radon computed by RAETRAD for test cell 2 was 20 pCi L"1, which was 10% below the mean of the measured values, 22 + 7 pCi L"\ With a 10-cm center hole in each slab, test cell 1 was computed to have an indoor radon concentration of 212 pCi L"1, which was 17% below the mean of the measured values, 255 ± 78 pCi L1. Test cell 2 with a center hole had a computed radon concentration of 87 pCi L'\ which was 18% above the mean of the measured values, 74 + 33 pCi i v
------- LComputed air pressure and radon concentration profiles under test cell 1 had relative standard deviations from measured values of 11 % and 12% respectively, which were smaller than the standard deviations among the replicate measurements. Computed air pressure and radon concentration profiles under test cell 2 had relative standard deviations from measured values of 25% and 20% respectively, which also were smaller than the standard deviations among the replicate measurements. Additional comparisons of RAETRAD calculations with radon measurements in the test cells were performed with test cell 2 at indoor pressures of -10 Pa and -20 Pa instead of its passive-condition pressure of -0.6 Pa. For the -10 Pa condition, test cell 2 was computed to have an indoor radon concentration of 51.5 pCi L', which was 3% higher than the measured 50 pCi L'1 value. For the - 20 Pa condition, an indoor radon concentration of 42.9 pCi L1 was computed by RAETRAD, 14% lower than the measured value of 50 pCi L"1. Collectively, the six model comparisons with indoor radon measurements in the test cells had an average difference of 11 %, with an average bias of -3%. Comparisons of RAETRAD calculations with indoor radon measurements in 50 FRRP demonstration houses exhibited much larger variations (geometric standard deviations of 2.8), and a bias of a factor of 0.56 below the measured values. This was attributed to the much less detailed characterization of the houses, primarily with respect to the concrete slab integrity and diffusivity. Significant unobserved holes or cracks (>50 cm2) near utility penetrations or by walls, bathtubs, or other features could cause this much bias, as could a 3-fold higher radon diffusion coefficient than was used for the floor (0.001 cm2 s'1)- Observations and measurements support either of these possibilities. ABSTRACT The report describes the theoretical basis, implementation, and validation of the RAdon Emanation and TRAnsport into Dwellings (RAETRAD) model, a conceptual and mathematical approach for simulating radon (222Rn) gas generation and transport from soils and building foundations to the indoor environment. It has been implemented in a computer code of the same name to provide a relatively simple, inexpensive means of estimating indoor radon entry rates and concentrations. RAETRAD uses the complete, multi-phase differential equations to calculate radon generation, decay, and transport by both diffusion and advection (with pressure-driven air flow). The equations are implemented in a steady-state, 2-dimensional finite-difference mode with elliptical-cylindrical geometry for maximum efficiency and modeling detail. For validation, the air flow part of RAETRAD was compared with a 2-dimensional analytical calculation of air flow through a uniform field. Variations of
Look, I should be clear—I didn’t want anything to do with “the dread lord,” or whoever Januk was talking about. I was just trying to sell this stupid little vial to the guy who asked me to get it for him. Should have been easy.
But when you’re me, nothing goes your way for long.
My way. Whatever.
Januk was a red-bearded Freljordian transplant, with deep pockets and big appetites. Unknown to his employers, his private residence was filled with relics and artwork, half of it raided illegally from tombs or other museums, and he loved to dine amidst his collection. As some of the pieces would attest, we’d worked together several times in the past, and he only betrayed me twice. Well, two eset smart security premium license key a half times, if I’m counting when he blew my cover after we had already salvaged the wreck of the Echelon Dawn…
To Januk’s credit, payment was never a problem, which vastly diminishes my ability to hold a grudge.
“Ezreal,” he said, pushing his plate aside. There were flecks of lamb in his teeth. “Did you find it?”
The it he was referring to was to the Elixir of Uloa. And yes, I had indeed liberated it from a trap-strewn hovel in the jungle near Paretha. I pulled the bone and crystal vial from my satchel. It was cool in the palm of my hand.
“Got what you’re looking for right here,” I said, holding up the vial. “Interesting container. My best guess would be pre-classical Shuriman.”
The spoonful of viscous liquid inside it shimmered in the moonlight. Januk’s eyes widened.
I decided to ramp up the drama. “I tell you what, though—this here isn’t just any ordinary ancient serum. It’s a load bearing ancient serum. The whole place crumbled around me. I barely escaped with my life.”
“The Elixir…” Januk’s voice took on a reverence I had never heard before. “A single drop can quench the soul for a thousand years… Give a man skin as tough as petricite…”
He went to grab it with his greedy hands. I pulled it out of reach.
“Not so fast, Januk.”
“Right, right, right,” he muttered, fumbling for his desk drawer key. “Payment. We agreed sixty thousand.”
“And full accreditation in the Guild, remember?”
I’d been f.lux 4.75 Latest Version Crack Key For U entry to plenty of things, in my time. Drive snapshot raid Free Activators, schools, even a Sona recital… but the Piltover Explorers Guild was the one that stung the most, considering the number of times I’ve risked my neck in the field. Ingrates.
Januk was scowling. “The Guild aren’t particularly fond of you, Ezreal. Can’t say I blame them, having worked with you in the past.” He poured himself some amberwine from a decanter and took f.lux 4.75 Latest Version Crack Key For U swig. “You left me to rot in that Noxian prison camp…”
“That was payback. For the Echelon Dawn.”
“Which was payback for the map.”
“Which was payback for… something else you did.” I gritted my teeth. “Probably.”
I was getting antsy. I readied myself to make a quick exit.
“Come on, accreditation was half the deal,” I reminded him. “If you don’t want to honor it, I can always find another buyer.”
His boisterous laugh broke the tension. “Why do you think I continue to do business with you? It’s because I like you. We have history, and history is always good for business.” He finished his drink. “Let me fetch the letter from my study. One moment, please.”
Buyers keeping payment in their studies? Oldest trick in the book. He’d probably return aiming a flintlock at my pretty face.
To kill time, I perused his collection of artifacts. There were some I had procured on his behalf. Then my eyes fell on something I had not seen before. Something new—a stone bell, roughly the size of a housecat. Its base was adorned with strange writing. I stepped closer to inspect it.
“It’s Ochnun,” Januk called out. “The language of the dead, composed beyond the mortal veil, and spoken only by those in the afterworld.”
I was getting some serious backstabby vibes, so I spun around.
Januk didn’t have a flintlock. He had two flintlocks.
“I am sorry to inform you, Ezreal, that the Guild has once again denied your application.” He stepped closer, into the light. “The dread lord will rise again. And the Elixir will make it happen.”
A dread lord? Great. I was so close this time…
My gauntlet’s charge rose. Anger is a keyshot 5 license file free download arcane motivator. Use it or lose it, I always say, f.lux 4.75 Latest Version Crack Key For U.
I raised my arm. Januk fired his pistols. It was magic versus lead shot.
Surprise! Magic won. Magic always wins.
The dull metal slugs burned white-hot in the face of my blast, and winked into silvery vapor on the other side. But with double-crossers, one must be doubly careful, so I quickly charged my gauntlet again. There was a slight fizzle, then a pop, and then I was standing right behind Januk, f.lux 4.75 Latest Version Crack Key For U. Teleporting short distances doesn’t really take a lot out of me, f.lux 4.75 Latest Version Crack Key For U I put my gauntleted hand to the back of his big, stupid head before he could turn around.
“Drop the guns, Januk.”
“Already one step ahead of you.”
Oh, I did not like the sound of that. I glanced down. Sure enough, the pistols were at his feet.
Did I mention Januk was strong? Because he is super strong. He grabbed my gauntlet in one hand, yanked me over his shoulder with the other, and slammed me bodily through his work desk. The damn stone bell jabbed into my spine. I saw white, and splinters. Lots of little splinters.
Januk kicked me in the ribs for good measure. He twisted the Elixir of Uloa out of my shaky grip, pulled the stopper, and drank deep.
“Your pathetic gauntlet will do nothing to an immortal! The Elixir is—”
“Fake,” I croaked. “Almost the right hues, though.” I held up another, far less remarkable looking vial. “This is the real Elixir. You just drank sand wasp venom, f.lux 4.75 Latest Version Crack Key For U, out of a cheap souvenir trinket vessel.”
Januk peered into the f.lux 4.75 Latest Version Crack Key For U vial, his face scrunched up like he’d tasted sour milk. In fairness, sour milk would have been a lot better for his digestive system.
I winced as pulled myself back to my feet. He had kicked me unnecessarily hard, but at least he spared my face.
“If I were you, I wouldn’t stray too far from a lavatory for the next few days,’ I added.
He threw the fancy casing to the ground, doubled over, and groaned. Sand wasp venom hits hard and fast. “You… petulant little… I’ll get you… for this…”
I shrugged, then raised my gauntlet and fired another blast of magical energy at the wall. The masonry cracked, melted and exploded outwards. Papers flew everywhere. I picked up the bell, and crouched by Januk’s new window.
“Always a pleasure, ” I said. “I won’t charge you for the, uhh… remodeling.”
I hopped out through the hole, scampered down the masonry and leapt across to a nearby rooftop. I wanted to be far away from Januk as quickly as possible, for lots of reasons. Admittedly, the sand wasp venom was the main one—it was not going to be pretty in that place by morning.
As I ran, I took a closer look at my latest acquisition. Whatever else it was, the Ochnun bell was definitely touched by some darker energy. Once the Explorers Guild got a load of this piece, I’d be a shoo-in for accreditation. With a party in my honor, perhaps? After all, I had just single-handedly kept some dread lord from rising.
And in the end, that’s usually all that matters.
------- EPA REVIEW NOTICE This f.lux 4.75 Latest Version Crack Key For U has been reviewed by the U.S. Environmental Protection Agency, and approved for publication. Approval does not signify thai iobit uninstaller 8.5 crack Activators Patch contents necessarily reflect the views and policy of the Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This document is available to the public through the National Technical Informa- tion Service, Springfield, Virginia 22161.
------- EXECUTIVE SUMMARY The RAETRAD (RAdon Emanation and TRAnsport into Dwellings) model has been developed to provide a simple, inexpensive means of estimating the rates of radon gas entry into dwellings from underlying soils. It can represent slab-on-grade houses of different sizes and shapes on soils with any distribution of radon source strengths, physical properties, water contents, f.lux 4.75 Latest Version Crack Key For U, and gas transport properties. It was developed in part under the Florida Radon Research Program (FRRP), which has been co-sponsored by the Florida Department of Community Affairs (DCA) and the U.S. Environmental Protection Agency (EPA). It has been used in the FRRP to characterize the effects of foundation soil and fill properties on indoor radon entry, to characterize the modes of radon entry, to characterize soil radon potentials for mapping of their geographic distributions, to develop simplified lumped-parameter models, and to support development of radon-protective building construction standards. RAETRAD computes radon production from radium decay, radon interactions in the solid, liquid, and gas phases of soils and concretes, and radon gas transport and indoor entry by both diffusion (concentration-driven) and advection (with pressure-driven air flow). It solves LaPlace's equation in steady state to define air pressure distributions under and near the house and to obtain air f.lux 4.75 Latest Version Crack Key For U velocities that are used in the radon calculations. The IsoBuster Pro License key differential equation also is solved in steady state, and incorporates the air velocity field in computing simultaneous diffusive and advective radon transport. The equations are solved numerically in elliptical-cylindrical geometry to represent houses of different sizes and with varying rectangular aspect (length/width) ratios. Radon entry rates into a house are computed by integrating the total radon transport across the floor surface area. Indoor radon concentrations also are estimated from the computed entry rates by dividing by the house volume and its air ventilation rate, f.lux 4.75 Latest Version Crack Key For U. Several analytical functions are used in RAETRAD to enhance its computational efficiency and to simplify its user interface. The numerical calculations of air flow and radon transport through floor cracks are accelerated by use of analytical functions to estimate the mesh-equivalent permeabilities and radon diffusion coefficients for the specified cracks rather than using finely-graded numerical meshes to represent them. Analytical functions also are used to define soil radon diffusion coefficients and air permeabilities for cases in which measured values are unavailable. These use soil porosities, water contents, and textures to define the radon transport properties from empirical correlations with measured data. In addition to modeling symmetric cracks in the floor slab, RAETRAD also accommodates asymmetric openings such as utility penetrations that do not match the elliptical symmetry computed for the equivalent rectangular house shape. These are represented by multiple numerical calculations that determine transverse leakage terms for the discrete-point floor openings. The numerical-analytical calculations are performed by computing all finite-difference coefficients for each model mesh unit and solving the equations simultaneously by a non-iterative matrix inversion technique. The resulting computer code is relatively small and efficient, and operates on an IBM"- compatible personal computer. Typical execution times are on the order of 1-2 minutes or f.lux License Key Crack Key For U, depending on the complexity of the problem being solved and the speed of the computer. A user interface provides queries for definition of an input file and selection of appropriate input parameters. i i i
------- The RAETRAD code was validated and benchmarked by several comparisons with analytical calculations and with empirical radon data. The analytical validations included comparison with a 2-dimensionaJ air pressure field calculated for a simple uniform 15 ft. x 31 ft. soil space with two different pressures applied at its top surface, f.lux 4.75 Latest Version Crack Key For U. Relative standard deviations of less than 1 % were obtained between the RAETRAD calculations and the analytical pressure field at the 1- 2- 4- 8- and 15-ft. depths below the pressure boundary. Analytical validations with 1-dimensional radon generation and diffusion from an open soil and a concrete-covered soil suggested the utility of defining a small (0.1-ft) mesh unit at the top of the soil profile to minimize the effects of mesh spacing. In these comparisons, both soil radon profiles and surface radon fluxes agreed consistently within less than 1%. Additional 1-dimensional validations included a uniform soil with radon generation, diffusion, and advective transport. In this case, the air flow velocities were forced by an external definition of a uniform pressure gradient, since RAETRAD is designed to compute only realistic, 2-dimensional pressure profiles. Again, agreement was within less than 1 % for all cases of air flowing into the soil profile. When air was drawn from the profile, a depletion of the profile was observed that caused a maximum error of 4% for the case that was analyzed. This error was reduced by considering a thicker soil profile, and was exaggerated if a thin soil layer was considered. Comparisons of RAETRAD calculations with empirical radon measurements utilized two test-cell structures (6 m x 6 m) constructed in South-Central Florida and monitored primarily by Southern Research Institute (SRI). One of these structures (test cell Freemake Video Converter 4.1.10.354 Crack key!! utilized floating-slab floor construction with concrete-block stem walls over a concrete footing. The other structure had similar footings and stem walls, but its floor slab was poured to extend into a course of chair blocks at the top of the stem wall. Both cells had identical wood-frame superstructures, without windows, that were sealed with 2-3 cm of polyurethane foam to minimize air infiltration. Soil densities, radium concentrations, radon emanation coefficients, and moistures were measured in this project from numerous cores collected around and under the test cells. SRI provided measured soil radon and air permeabilities, and indoor pressures, air"ventilation, and radon concentrations. Field soil sampling at the test cell site extended only to 4-7 ft. depths for most cores; hence deeper soil regions were extrapolated from existing moisture and radium data. Calculated radon concentration profiles were within 4.4% of the means of measured values under test cell 1, compared to a 34% root-mean-square uncertainty among the measured values. Calculated radon profiles were within 18% of the means of measured values under test cell 2, compared to a 42% root-mean-square uncertainty among the measured values. Measured soil air permeabilities differed from values calculated from soil density, moisture and texture by 42%sbased on composite averages at four different depths. Excluding a heterogeneous, low-permeability layer under part of the site, the agreement was improved to 24% relative standard deviation. Indoor radon in the test cells was analyzed by RAETRAD to compare with measurements before and after drilling a center hole in each of their slabs. For the initial slab conditions, RAETRAD computed 97 pCi L"1 in test cell 1, only 2% above the mean of the measured values, 95 ± 44 pCi L'1. The radon computed by RAETRAD for test cell 2 was 20 pCi L"1, which was 10% below the mean of the measured values, 22 + 7 pCi L"\ With a 10-cm center hole in each slab, test cell 1 was computed to have an indoor radon concentration of 212 pCi L"1, which was 17% below the mean of the measured values, 255 ± 78 pCi L1. Test cell 2 with a center hole had a computed radon concentration of 87 pCi L'\ which was 18% above the mean of the measured values, 74 + 33 pCi i v
------- LComputed air pressure and radon concentration profiles under test cell 1 had relative standard deviations from measured values of 11 % and 12% respectively, which were smaller than the standard deviations among the replicate measurements. Computed air pressure and radon concentration profiles under test cell 2 had relative standard deviations from measured values of 25% and 20% respectively, which also were smaller than the standard deviations among the replicate measurements. Additional comparisons of RAETRAD calculations with radon measurements in the test cells were performed with test cell 2 at indoor pressures of -10 Pa and -20 Pa instead of its passive-condition pressure of -0.6 Pa. For the -10 Pa condition, test cell 2 was computed to have an indoor radon concentration of 51.5 pCi Letasoft Sound Booster 1.11.0.514 Crack + Product Key With Full Keygen 2021, which was 3% higher than the measured 50 pCi L'1 value. For the - 20 Pa condition, an indoor radon concentration of 42.9 pCi L1 was computed by RAETRAD, 14% lower than the measured value of 50 pCi L"1. Collectively, the six model comparisons with indoor radon measurements in the test cells had an average difference of 11 %, with an average bias of -3%. Comparisons of RAETRAD calculations with indoor radon measurements in 50 FRRP demonstration houses exhibited much larger variations (geometric standard deviations of 2.8), and a bias of a factor of 0.56 below the measured values. This was attributed to the much less detailed characterization of the houses, primarily with respect to the concrete slab integrity and diffusivity. Significant unobserved holes or cracks (>50 cm2) near utility penetrations or by walls, bathtubs, or other features could cause this much bias, as could a 3-fold higher radon diffusion coefficient than was used for the floor (0.001 cm2 s'1)- Observations and measurements support either of these possibilities. ABSTRACT The report describes the theoretical basis, implementation, and validation of the RAdon Emanation and TRAnsport into Dwellings (RAETRAD) model, a conceptual and mathematical approach for simulating radon (222Rn) gas generation and transport from soils and building foundations to the indoor environment. It has been implemented in a computer code of the same name to provide a relatively simple, inexpensive means of estimating indoor radon entry rates and concentrations. RAETRAD uses the complete, multi-phase differential equations to calculate radon generation, decay, and transport by both diffusion and advection (with pressure-driven air flow). The equations are implemented in a steady-state, 2-dimensional finite-difference mode with elliptical-cylindrical geometry for maximum efficiency and modeling detail. For validation, the air flow part of RAETRAD was compared with a 2-dimensional analytical calculation of air flow through a uniform field. Variations of
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