At the outset of a project, the estimate cannot be expected to carry a high degree of accuracy, because little information is known. As the design progresses, more information is known, and accuracy should improve. Estimating at any stage of the project cycle involves considerable effort to gather information. The estimator must collect and review all of the detailed plans, specifications, available site data, available resource data (labor, materials, and equipment), contract documents, resource cost information, pertinent government regulations, and applicable owner requirements. Information gathering is a continual process by estimators due to the uniqueness of each project and constant changes in the industry environment. Unlike the production from a manufacturing facility, each product of a construction firm represents a prototype. Considerable effort in planning is required before a cost estimate can be established. Most of the effort in establishing the estimate revolves around determining the approximation of the cost to produce the one-time product. The estimator must systematically convert information into a forecast of the component and collective costs that will be incurred in delivering the project or facility. This synthesis of information is accomplished by mentally building the project from the ground up. Each step of the building process should be accounted for along with the necessary support activities and embedded temporary work items required for completion.

The estimator must have some form of systematic approach to ensure that all cost items have been incorporated and that none have been duplicated. Later in this chapter is a discussion of alternate systematic approaches that are used.

The quality of an estimate depends on the qualifications and abilities of the estimator. In general, an estimator must demonstrate the following capabilities and qualifications:

• Extensive knowledge of construction
• Knowledge of construction materials and methods
• Knowledge of construction practices and contracts
• Ability to read and write construction documents
• Ability to sketch construction details
• Ability to communicate graphically and verbally
• Strong background in business and economics
• Ability to visualize work items
• Broad background in design and code requirements
• Broad background in design and code requirements

Obviously, from the qualifications cited, estimators are not born but are developed through years of
formal or informal education and experience in the industry. The breadth and depth of the requirements
for an estimator lend testimony to the importance and value of the individual in the firm.

Construction is the realization phase of the civil engineering process, following conception and design. It is the role of the constructor to turn the ideas of the planner and the detailed plans of the designer into physical reality. The owner is the ultimate consumer of the product and is often the general public for civil engineering projects. Not only does the constructor have an obligation to the contractual owner, or client, but also an ethical obligation to the general public to perform the work so that the final product will serve its function economically and safely.

The construction industry is typically divided into specialty areas, with each area requiring different skills, resources, and knowledge to participate effectively in it. The area classifications typically used are residential (single- and multifamily housing), building (all buildings other than housing), heavy/highway (dams, bridges, ports, sewage-treatment plants, highways), utility (sanitary and storm drainage, water lines, electrical and telephone lines, pumping stations), and industrial (refineries, mills, power plants, chemical plants, heavy manufacturing facilities). Civil engineers can be heavily involved in all of these areas of construction, although fewer are involved in residential. Due to the differences in each of these market areas, most engineers specialize in only one or two of the areas during their careers. Construction projects are complex and time-consuming undertakings that require the interaction and cooperation of many different persons to accomplish. All projects must be completed in accordance with specific project plans and specifications, along with other contract restrictions that may be imposed on the production operations. Essentially, all civil engineering construction projects are unique. Regardless of the similarity to other projects, there are always distinguishing elements of each project that make it unique, such as the type of soil, the exposure to weather, the human resources assigned to the project, the social and political climate, and so on. In manufacturing, raw resources are brought to a factory with a fairly controlled environment; in construction, the “factory” is set up on site, and production is accomplished in an uncertain environment. It is this diversity among projects that makes the preparation for a civil engineering project interesting and challenging. Although it is often difficult to control the environment of the project, it is the duty of the contractor to predict the possible situations that may be encountered and to develop contingency strategies accordingly. The dilemma of this situation is that the contractor who allows for contingencies in project cost estimates will have a difficult time competing against other less competent or less cautious contractors. The failure rate in the construction industry is the highest in the U.S.; one of the leading causes for failure is the inability to manage in such a highly competitive market and to realize a fair return on investment.

Continuous-time signals:

This is the type of signal produced when we talk or sing, or by a musical instrument. It is ‘continuous’ in that it is present at all times during the talking or the singing. For example, if a note is played near a microphone then the output voltage from the microphone might vary as shown in Fig. 2.1. Clearly, continuous does not mean that it goes on for ever! Other examples would be the output from a signal generator when used to produce sine, square, triangular waves etc. They are strictly called continuous-time, analogue signals.

Discrete-time signals:

These, on the other hand, are defined at particular or discrete instants only- they are usually sampled signals. Some simple examples would be the distance travelled
by a car, atmospheric pressure, the temperature of a process, audio signals, but all recorded at certain times. The signal is often defined at regular time intervals.
For example, atmospheric pressure might be sampled at the same time each day (Fig. 2.2), whereas an audio signal would obviously have to be sampled much

more frequently, perhaps every 10/Is, in order to produce a reasonable representation of the signal. (The audio signal could contain frequency components of up to
20 kHz and so, to prevent aliasing, it must be sampled at a minimum of 40 kHz, i.e. at least every 25/~s.)

Digital signals

This term is used to describe a discrete-time signal where the sampled, analogue values have been converted to their equivalent digital values. For example, if the
pressure values of Fig. 2.2 are to be automatically processed by a computer then, clearly, they will first need to be changed to equivalent voltage values by means
of a suitable transducer. An ADC is then needed to convert the resulting voltages to a series of digital values. It is this series of numbers that constitutes the digital
signal.

The mechanics of what happens is surprisingly simple. First, a number of the previous input and/or output values are stored in special data storage registers, the number stored depending on the nature of the signal processing to be done. Weighted versions of these stored values are then added to (or subtracted from) the current input sample to generate the corresponding output value – the actual algorithm obviously depending on the type of signal processing required. It is this processing algorithm which is at the heart of the whole system – arriving at this can be a very complicated business! This is something we will examine in detail in later chapters. Here we will look at some fairly simple examples of processing, just to get a feel for what is involved.

Civil engineering professionals design, construct and maintain society’s infrastructure—buildings, bridges, roads, airports, dams, water supplies and environmental systems. With the intricacy involved in creating and updating infrastructure designs and projects, civil engineers must take into account not only construction costs but project completion time, government regulations and potential environmental hazards, such as earthquakes and hurricanes.

One of the oldest engineering disciplines, civil engineering plays a central role in communicating infrastructure ideas and solutions to local, state and federal government. And they make a strong effort to inform the public as well. The American Society of Civil Engineers (ASCE) publishes booklets and other resources to educate communities and clarify issues surrounding the latest infrastructure topics

What You’ll Do in a Computer Software Engineering Career

Computer science and software engineering professionals design and develop software applications, from video games to business applications to operating systems. Starting with a study of user needs, software engineers apply the principles of computer science, engineering and mathematical analysis to create, test and evaluate software applications and systems.

In general, software engineers fall into one of two categories:

• Applications engineers who use different programming languages, including C, C++ and Java, to develop and maintain software applications based on their own designs or designs created through a coordinated effort with business analysts or other customer experts.
• Systems engineers who focus on an organization’s internal computer systems. Their duties typically include researching, recommending and coordinating department- or company-wide computer needs, such as data assurance, system security and intranets.

Computer Software Engineering Job Opportunities

What You’ll Do in a Telecommunications Engineering Career

Good:

• Everybody comes to you when they need to know something (good job security).
•  You will always be able to find work (if not in engineering, then as a teacher; engineers make VERY GOOD teachers).
•  You start out making between 40k-60k a year straight out of school. And it can go up fast when you switch jobs and have good experience.
•  Everybody thinks you’re really smart.
• You never have to make minimum wage again.

Bad:

• 1) Everybody blames the engineer first. Well, everybody, except the engineer, but they think it. lol.
• 2) Horrible male to female ratio.
• 3) You have to work hard to get what and where you want.

The BLS reports that aerospace engineers earn a median annual salary of $92,520, the fourth highest median salary for all engineering specialties. Overall, annual salaries for aerospace engineers range from $58,130 to $134,570. And the top-paying states for aerospace engineers include: Maryland, California, the District of Columbia, New Mexico and Massachusetts.

Agricultural Engineer Salary

The BLS reports that agricultural engineers earn a median annual salary of $68,730. Overall, agricultural engineering annual salaries range from $43,150 to $108,470. Agricultural engineers who aim their careers toward the management, scientific and technical consulting services industry can anticipate the higher end of the salary range. Top-paying states for agricultural engineering? Maryland, Colorado, North Carolina, Arizona and Kentucky.

Biomedical Engineer Salary

What is an engineer?