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The ancestral principles of use of the Nile

An irrigation technique that is natural for the regimes of the Nile develops in the

IIIrd millennium BC. The flood regime of the Nile is quite regular in time, from June to October, but is obviously of quite irregular magnitude. The earliest agriculture consist­ed quite simply in planting seeds in the moist soil fertilized by silty flood deposits. But a flood of small magnitude inevitably precedes a year of famine:

“I was in mourning on my throne, Those of the palace were in grief… .because Hapy had failed to come in time. In a period of seven years, Grain was scant, Kernels were dried up…Every man robbed his twin…Children cried…The hearts of the old were needy…Temples were shut, Shrines covered with dust, Everyone was in distress..”

“My heart was greatly troubled for the Nile did not...

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THE COST OF CONGESTION

Congestion, when applied to traffic, refers to that condition which occurs when drivers experience a noticeable delay in completing a trip because of inability to maneuver through the traffic stream. This condition is characterized by slow travel speeds, increased travel times, increased accident frequencies, erratic stop-and-go driving, increased vehicle operating costs, and other undesirable circumstances leading to driver dissatisfaction (Ref. 4).

Congestion on urban freeways is of two types—recurring and nonrecurring. Congestion that occurs regularly at particular locations during certain time periods is said to be recurring...

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Permeability Testing

The permeability of soils is a material parameter that relates the rate of water flow to the hydraulic gradient in the soil and, therefore, determines the material’s suitabil­ity for drainage layers. An embankment usually consists of compacted materials. The compaction often results in anisotropy such that the vertical and the horizontal permeability properties are not equal. For road construction layers, water move­ments below the ground water table are almost entirely horizontal and thus it is the horizontal permeability that should be measured. Above the groundwater table in the unsaturated zone the movement of water is much more complex, involving vertical as well as horizontal components depending on material parameters such as temperature, water content and matric suction.

Some t...

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Part i: Coarse Aggregate Content

Designing the coarse aggregate part of an SMA mix differs widely from designing an asphalt concrete (AC) mix. The unexpected difference lies in the various results of similar actions. Let us consider the example of SMA gradation curves.

It should be kept in mind that SMA has a strong aggregate skeleton with little to none of the medium aggregate fraction. Different distributions of sizes within the coarse aggregate fraction can lead to greater or smaller discontinuities in the overall gradation in a course, which can lead to some pretty interesting consequences for the mixture.

Example i

MIXTURE S

Thus let us take the gradation limits of SMA 0/12.8 mm and insert a gradation curve between them, marking that design as S (Figure 6.2). Grading parameters of the mixture S are shown in Table 6...

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Other Methods

A number of other methods exist for estimating soil water content such as nuclear magnetic resonance (NMR), which can detect nuclear species that have a magnetic moment or spin. As hydrogen has a nuclear spin of 1/2 the NMR technique can be used to estimate water content in soils. This is a fast and non-destructive method with high accuracy in uniform samples. However the method is costly, not suitable for field use and highly dependent upon sample calibration and is therefore not used in soil studies or in applications related to roads (Veenstra et al., 2005).

Near infrared reflectance spectroscopy (NIRS), seismic methods and thermal properties are all methods that can be used for estimation of soil water content...

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Historical Points of Reference

The earliest Egyptian cultures evolve essentially in parallel with those of Mesopotamia, lagging only slightly. However in contrast to the agitated history of the Syro – Mesopotamian universe, the historical evolution in Egypt is relatively linear. The polit­ical unification of the twin lands (upper Egypt and the delta) occurs about 3100 BC, and clearly is the logical outcome of a common culture. This cultural and political union of the south and the north is a cherished aspiration of the Egyptians, and persists across the centuries despite several troubled periods. One of these periods is the separation of the ancient and middle Empires from 2180 to 2040 BC, and another is from 1730 to 1560 BC, a prelude to the establishment of the new Empire.

The middle and new Empires were marked by a ...

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INSTALLING SHINGLES

After attaching drip-edge flashing to the eaves and rolling out underlayment over the drip-edge, install the starter course along the eaves. You’ll cover the starter course with the first course of shingles. Running starter courses along the rakes isn’t imperative, but it’s smart because starters stiffen the overhanging shingle edges and create a cleaner line.

The starter course. First determine how much the starter course will overhang the drip-edge:

I in. to Va in. overhang is typical, but some roofers allow as much as 1 in. if eaves or rake boards are badly bowed. The starter course will be 7 in. high. Extend your tape measure past the drip – edge the amount of the overhang, and make crayon marks on the underlayment at 7 in. and at 12 in...

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Earth Energies: Choosing the Right Site

Choosing a site that avoids hazardous pollutants and then building with healthy materials are vital for creating a healthy home. The naturally occur­ring Earth energies, known as geopathic stress, are another important factor to consider. These ener­gies result from polar magnetism, underground domes, veinsand streams of water, radon gasemis – sions, electromagnetic waves, and seismic activity. Their effects can be seen in rockfaufts, fissures and geological stresses, power spots, vortices, mineral and ore deposits, and underground caves.

Their health effects can range from subtle to severe, with some being well accepted and oth­ers less recognized and sometimes controversial...

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Step 9-Subfloor Sheathing

Подпись:Подпись:7. Start second row with half sheet so ends will be staggered.

1. Chalk a line at
4′-%" on joists.

 

!/б" gap – larger if moist application (check with instructions on sheathing)

 

4. Pull layout on
sheathing.

 

3. Center sheathing to last joists and on chalk line, then nail,

 

6. Nail remaining joists, setting them to layout marks.

 

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Step 9-Subfloor Sheathing

Step 9-Subfloor Sheathing

Подпись: a

ЖЙЇЇЇЗйг

Six Steps for Setting First Sheet of Sheathing

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MAKING A BLOCK-CUTTING TOOL

Many carpenters cut blocks with a chopsaw, which is fine if you have one. But there is another easy way to cut blocks. Try making a simple block-cutting tool to use with a circular saw. Once you have the guide, simply hook it on a 2x and make the cut along the edge.

Подпись: That empty feeling. When installing sheathing, you can feel when a nail doesn't hit a joist—it goes in too easily. Driving a fresh nail to the left or right of the dud usually results in solid contact.

joists, bridging is often visible between the rim joists and the interior girders or crib walls in the basement or crawl space of an old house. Stress tests have long shown that bridging provides little extra stability to a floor sheathed with plywood or OSB. My experience is that most midspan bridging does little except increase floor squeaks.

Blocking between joists, on the other hand, helps stabilize a building and keeps the joists from falling like dominoes under severe lateral stress, such as that generated by an earthqua...

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