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Fundamental Rules of Probability Computations

Posted by on 11/ 11/ 15

2.1.1 Basic axioms of probability

The three basic axioms of probability computation are (1) nonnegativity: P (A) > 0, (2) totality: P (S) = 1, with S being the sample space, and (3) additivity: For two mutually exclusive events A and B, P(A U B) = P(A) + P(B).

As indicated from axioms (1) and (2), the value of probability of an event occurring must lie between 0 and 1. Axiom (3) can be generalized to consider K mutually exclusive events as

P (A1 U A2 U-.-U Ak ) = p( U aA =£) P (Ak) (2.2)

‘vk=1 ‘ k=1

An impossible event is an empty set, and the corresponding probability is zero, that is, P(0) = 0. Therefore, two mutually exclusive events A and B have zero probability of joint occurrence, that is, P (A, B) = P (0) = 0...

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Removal Methods and Containment

Posted by on 11/ 11/ 15

K. A. Trimbler has described and compared methods of lead paint removal. His findings are summarized in Table 1.15 and described below. (K. A. Trimbler, Industrial Lead Paint Removal Handbook, 2d ed., Steel Structures Painting Council/KTA-Tator, Inc., Pittsburgh, 1993, and personal communication, August 2002.)

Quality of preparation Debris created

Rust/mill

Equipment

investment"

Paint removal^

scale removal^

Quality for painting"

Dust

Method and name

Flat

Irregular

Flat

Irregular

generation^

of debris^

required^

rate"

Method 1. Open abrasive blast cleaning with expendable abrasives

2-4 f

5

5

5

5

5

і

і

1-2

5

Method 2. Open abrasive blast cleaning with recyclable abrasives

1

5

5

5

5

5

3

4

1

5

Method ...

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Design Constraints

Posted by on 11/ 11/ 15

Information you’ve gathered thus far will be use­ful whether you’re hiring a general contractor and an architect or trying to tackle various parts of the job yourself. But before you begin explor­ing design solutions, consider realities that will have an impact on your plans.

BUDGET CONSTRAINTS

Consult a licensed general contractor (GC) about construction costs, especially before asking an architect to generate a lot of design options, called schematic drawings. An experienced con­tractor can cite construction costs per square foot in your region but may be reluctant to do so without qualifying those estimates. Such quali­fiers will be well founded because every renova­tion is different, and there’s no way of knowing what surprises a job holds till you open up walls and floors...

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Review of Materials Applied as Fillers

Posted by on 11/ 11/ 15

3.2.4.1 Commercially Produced Fillers (Added Fillers)

According to European terminology,! added fillers are made by crushing stone to produce fillers aimed at use in highway engineering. For a long time, the most popu­lar of these has been, and is likely to remain, limestone filler. Limestone filler is distinguished by its affinity with binder, which is one of its strong points. Therefore in Europe limestone filler is most often used for SMA.

The other important feature of industrially manufactured fillers is their repeat­ability and uniformity of parameters. Finally it is worth observing their constant and repeatable mineralogical composition.

3.2.4.2 Fly ashes

The use of fly ashes as fillers for SMA is uncommon...

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Mortar—F:B Index

Posted by on 11/ 11/ 15

One popular approach used during design practice in many countries is to indicate the recommended range of the filler-bitumen ratio (or F:B index) by weight or vol­ume. Researchers in the United States have said that this factor better describes the maximum content of filler in the mix than does setting specific limits on the filler content. It is also worth adding that those studies have defined the maximum F:B index for asphalt concrete at the level of 1.2-1.5 (by weight) (Anderson, 1987). The F:B index was later altered to 0.6-1.6 in the Superpave method (Superpave Mixture Design Guide. WesTrack Forensic Team Consensus Report, 2001). Finally the sug­gested F:B ratio for SMA mixes is at 1...

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USING DRILLS

Posted by on 11/ 11/ 15

Old drills were made with enclosed trigger guards like those on firearms. Carpenters had their trigger fingers caught and broken from time to time, such as when a drill bit got hung up on a knot in a board and spun suddenly. For safety reasons, workers often used a hacksaw to cut out the trigger guards. These days, manufac­turers have eliminated trigger guards, but that doesn’t mean drills can’t do you harm. To use a drill safely, follow these guidelines:

■ Use clean, sharp bits.

■ Don’t force the drill; let it cut at its own pace.

■ Use a slower speed when drilling harder materials, and coat the bit with wax or silicone to reduce resistance.

■ When drilling thick material, hold the drill with both hands, and use the side handle if the drill comes with one.

■ If you’re drilling a deep hol...

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Idea of Voids in Dry-Compacted Filler

Posted by on 11/ 11/ 15

Let us imagine a set of grains that are going to be dry-compacted by tamping.[13] The result will be a mixture with its volume consisting of grains and some free spaces among them. In a regular binder mortar (blend of filler and binder), these free spaces in a compacted filler would be occupied by binder. The rest of binder would remain as excess filler. Thus binder contained in a mortar can be divided into the following two types (Figure 3.2):

Подпись: Volume of binderПодпись:Подпись:Подпись:Подпись:image22"

Idea of Voids in Dry-Compacted Filler

Bulk volume of compacted mineral filler

FIGURE 3.2 Free and fixed binder concept. (From Harris, B. M. and Stuart, K. D., Journal of the Association of Asphalt Paving Technologists, 64, 54-95, 1995; Kandhal, P. S., Journal of the Association of Asphalt Paving Technologists, 50, 150-210, 1981. With permission.)

• Fixed binder—binder inside th...

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MAPPING STRUCTURE AND UTILITIES

Posted by on 11/ 11/ 15

Renovations beyond cosmetic changes will prob­ably require some alteration of the structure as well as of plumbing, electrical, and heating/ cooling systems. As with many other aspects of renovation, it’s usually best to disturb as little as possible. Until you demolish walls you won’t know the exact location of every last pipe and wire, but by mapping what you can see, you’ll get a sense of where larger, more problematic ducts and pipes are, and thus save time and money by not proceeding with an obviously impractical design.

Now, using the floor plans you drew earlier as templates, create a map for each house system. For each system, use a tracing-paper overlay or mark up a photocopy of the basic floor plan, whichever is more convenient...

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Introduction

Posted by on 11/ 11/ 15

L

ight wood-frame construction originated in this country over 150 years ago and quickly evolved into the predominant construction system for houses and other small-scale buildings. Today, over 90% of all new buildings in North America are made using some version of this method. Remodeling projects follow the same track.

There are many reasons why this system has been the choice of professional and amateur builders alike over the years. A principal reason is its flexibility. Because the modules are small, virtually any shape or style of building can be built easily with the studs, joists, and rafters that are the primary components of wood-frame construction...

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Costs and Reports Vary

Posted by on 11/ 11/ 15

Whether a basic inspection or an in-depth scientific test, an auditor’s findings will likely be output from software that not only takes into account the physical data about the structure but also data about utility bills, the local climate, and, possibly, comparative information from other houses.

A CMC-trained auditor will generate a report about the existing house’s needed im­provements, including a cost-benefit analy­sis and payback time in years. CMC doesn’t control what its inspectors charge, but Luxton says audits cost from $200 to $400, depending on the size of the house.

RESNET auditors are licensed to use com­pany software that produces a HERS-index report. An audit with a HERS report (report fees can run around $150) costs from $1,000 to $1,500...

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