Blog Archives

Microwave Ovens Are Tops in Efficiency

Posted by on 26/ 11/ 15

First introduced as a practical kitchen appliance in 1965, microwave ovens have revolutionized cooking and offer substantial energy savings over standard ovens (They are 5 times as energy efficient as a standard electric oven). They work by producing non-ionizing microwave radiation (a certain frequency of radio waves) with a magnetron and directing that radiation at the food. The microwave radiation is absorbed by water, fats, and sugars, producing heat. Because the microwaves penetrate the food, heating is more rapid and requires less energy than in a conventional oven. Microwave ovens are about

5 times as energy efficient as standard elec­tric ovens and more than 10 times as energy efficient as gas ovens.

Increasingly, manufacturers are combining cooking functions with microwave ovens ...

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Surface Seals

Posted by on 26/ 11/ 15

For pavement seals the following materials are used:

• asphalt layers;

• stress absorption membranes (“SAMIs”) (see Fig. 13.37); and

• junction sealing material.

SAMIs act over an old cracked pavement surface, sealing the cracks against wa­ter ingress. They often provide a small degree of differential horizontal movement between an old and a new pavement layer so that the relative movements of the parts of the old pavement either side of a crack do not cause a stress concentration in the new, overlying, pavement layer at the same point. Without this ability, a crack in the new layer can quickly form immediately above the old crack – a problem known as “reflection cracking”. Water can then, very quickly, re-enter the road and the overlay will not act as an effective seal (e. g...

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SEWAGE PUMPS

Posted by on 26/ 11/ 15

Подпись: ✓ fast code fact Exterior sewage pumps must be equipped with alarm systems. The alarms warn the property owner if the pump is not operating and the pump station is filling with sewage. Without the alarm, the sewage could build to a point where it would flow back into the building. Подпись: been there done that Some homeowners associate an overflowing toilet with a problem in their septic system. It is possible that the septic system is responsible for the toilet backing up, but this is not always the case. A stoppage either in the toilet trap or in the drainpipe can cause a backup. There are times when sewage pumps must be used to get sewage to a septic system. The pumps are normally installed in a buried box outside of the building being served. The box is often made of concrete. In these cases, the home’s sewer pipe goes to the pumping station. From the pumping station, a solid pipe transports the waste to the septic tank.

Подпись: FIGURE 14.10 ■ Example of a pump-station septic system.

sewage pumps have floats that are lifted as the level of contents in the pump station build. When the float is raised to a certain point, the pump cuts on, emptying the contents of the pump station. The dis­charge pipe from the pump must be equipped with a check valve. otherwise, gravity would force waste down the pipe, back into the pump station, when the pump cut off...

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Land development and management

Posted by on 26/ 11/ 15

The minor lay lords of the middle ages were all too often uninterested in the manage­ment of the land, or sometimes were simply incapable of applying techniques that went beyond their competence. So it was the monks, and in particular the Benedictines and Cistercians, who became the custodians of land development during the demographic expansion of the 12th and 13th centuries. We have already seen that these monks were quite competent in such matters.

The biggest hydraulic project for reclaiming land from the sea and swamps was in coastal Flanders. Actually there were several distinct operations, but all of them were rather similar and conducted until about the year 1300...

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Information Phase

Posted by on 26/ 11/ 15

Objectives. The first phase of the job plan has two basic objectives:

To obtain thorough understanding of the project, system, operation, or item under study by a rigorous review of all of the pertinent factual data

To define the value problem by means of functional description accompanied by an estimate of the cost and worth of accomplishing each basic function

Key questions. During this phase, the following key questions must be answered:

What is it?

What does it do?

What must it do?

What does it cost?

What is it worth? (What is the least the function could cost?)

Procedure

1. Use good human relations. The matter of human relations is of utmost impor­tance to the success of any VE study. “People” problems are sometimes more difficult to resolve than technical problems...

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Resistance to Fuel on Airfields

Posted by on 26/ 11/ 15

This requirement regarding resistance to fuel exclusively applies to SMA mixes for airfields. The method of testing this property of SMA is elaborated in the standard EN 12697-43. The categories of the requirements are good, moderate, poor, or NR (no requirement).

14.5.11 Resistance to Deicing Fluids for Application on Airfields

This requirement concerning resistance to deicing fluids applies to SMA mixes for airfields only. The method of testing this property of SMA is described in the stan­dard EN 12697-41. The test is conducted using the pull-off method on samples sub­jected to conditioning in a deicing fluid and on nonconditioned, comparable samples. The categories of requirements are marked with the indexed symbol в: P100, в 85, P70, P55, and PNR, where PNR means no requirement...

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Multiple-Framer Tasks

Posted by on 26/ 11/ 15

Some tasks require more than one framer, for example, lifting large walls. Any time framers have to be called from other tasks to perform a common task, care must be taken not to waste time. The cost per minute of a 5-framer task is 5 times that of a single framer task. The person organizing the task needs to take responsibility for making sure the task is ready for all framers. If it is lifting a wall, the organizing framer should make sure the wall is completely ready so framers don’t stand around while one person makes last-minute adjustments.

Learning Curve

Studies have been done that show that as output is doubled, the time required decreases according to a constant ratio. The common ratio is about 4 to 5, or 20%...

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Additional Conditions for Preparing Samples

Posted by on 26/ 11/ 15

The SMA wheel tracking test is carried out on samples (slabs) prepared in a labora­tory or cut out of a pavement. Additional requirements for samples may be deter­mined in the following two ways:

• Requiring a void content in the slab; in this case the requirement has a range of 3% (v/v), (e. g., 3-6% [v/v]).

• Requiring the compaction factor; in this instance a requirement with a range of 2% (e. g., 98-100%) should be imposed.

All the aforementioned requirements actually specify the quality of the prepared sample (slab) before testing.

14.5.10 Reaction to Fire

When an SMA mix has to meet requirements for resistance against fire specified in other regulations, this property should be tested and classified according to the method described in EN 13501-1.

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Radio Frequency Radiation

Posted by on 26/ 11/ 15

The higher the frequency of the electromagnetic

radiation, the more the electric and magneticfield components meld. The energy level of radio fre­quency (RF) radiation is billions of times stronger than the natural high-frequency energies from the cosmos that existed during our biological de­velopment. Research shows that cataracts, blood composition changes, hormone alterations, and chromosomal abnormalities are induced at high – frequency energies.0 Sources of high RF radiation located outside a home require changing the lo­cation of the bed or shielding with RF-reflective paint and/or material.

Internal RF sources, such as cellular phones, wireless communications, and cordless phones, should not be in or near the bedroom, or at least not while you sleep. Cordless phones based on 2...

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VALUE ENGINEERING JOB PLAN DETAIL

Posted by on 26/ 11/ 15

The VE job plan outlines those tasks or functions necessary to properly perform a VE study. Adherence to a definite plan is essential to achieving optimum results. Good results come from a good system, and a good system is one that covers all aspects of a problem or situation to the necessary degree. Use of the job plan provides

1. A vehicle to carry the study from inception to conclusion

2. A convenient way to maintain a written record of the effort as it progresses

3. Assurance that consideration has been given to facts that may have been neglected in the creation of the original design

4. A logical separation of the study into units that can be planned, scheduled, budgeted, and assessed

5...

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