- Civil engineering is the grandparent of all engineering
- Engineering suceeds and fails because of the black box - it conceptually contains the knowledge and processes of an engineering specialty
- You are a vector - a force is expressed graphically by a vector. Any single vector can be replaced by more than one component vectors, and vice versa, as long as they yield an equivalent net result
- When overwhlemed by a complex problem, identify those aspects of it that can be grasped with familiar principles and tools
- An object receives a force, experiences a stress (force / area), and exhibits strain (measurable deformation)
- 4 material characteristics - stiffness/elasticity (resistance to change in length/ability to return to original size and shape), strength (ability to accept a load), ductility/brittleness (extent a material deforms or elongates before fracturing), toughness (overall measure of ability to absorb energy before fracture)
- A battery works because of corrosion - electrons moving to the cathode from the anode
- Soldiers shouldn't march across a bridge - when a force acts repeatedly on a structural member, and at a rate that matches its natural frequency, the member's response is enhanced with every cycle
- Roundabouts are teh safest, most efficient intersection
- Maximum friction is found right at the start of motion and declines immediately when motion starts
- Accuracy is the absence of error, precision is the level of detail - effective problem solving requires always being accurate, but being only as precise as is helpful at a given stage of problem solving. Early in the problem solving process, accurate but imprecise methods, rather than very exact methods, will facilitate design explorations while minimizing the tracking of needlessly detailed data
- Good design is not maximization of every response, or even compromise among them; it's optimization among alternatives
- Quantification is exact not unto reality, but unto itself, it is approximation of reality
- You don't fully understand something until you quantify it. But you understand nothing at all if all you do is quantify
- Safety margins are constantly used by engineers, overestimating loads, rounding calculations, selecting for structures larger or thicker than calculations call for
- The complexity of a truss is a product of simplicity - allowing long distance bridges to be built using a fraction of the material used by an ordinary beam
- Structures are built from the bottom up, but designed from the top down
- Earthquake design: let it move a lot or not at all
- Figuring out how to make a system work is as important as figuring out how to make it not work in undesirable ways
- A masonry arch (keystone) gets stronger as it does more work
- Early decisions have the greatest impact on design, feasibility, and cost
- Perfect reliability isn't always desirable - some aircraft parts are meant to be replaced frequently in order to save time, weight,
- Few customers will pay for a perfectly engineered part - trade off between cost and value
- Design a part to fail - electrical systems are protected by fuses or circuit breakers that trip before a power surge can ruin expensive components or damage ahrd to access wires
- Turbulent flow is when particle paths are irregular and laminar flow occurs when particles move in straight lines (low flow velocities and small pathways)
- Think systematically - apply your thinking consistently and thoroughly to all other aspects of the problem at all possible scales, from concept to detail and back again
- Think systemically - thinking about systems and connections - the web of relationships within a system, the relationship of the system to other systems, and the larger system that contains all the systems
- A successful system won't necessarily work at a different scale
- See JBS Haldane On Being the Right Size
- Seek negative feedback - a system responds in the opposite direction of the stimulus, bringing overall stability or equilibrium (positive feedback decreases equilibrium further and further)
- Center of gravity - the center of gravity of an object is the average position of the particles that comprise it - the point on which it will balance
- Articulate the why, not just the what - by articulating your intent, you help others understand and preserve the most critical goals while giving them room to investigate possibilities that did not occur to you
- All engineers calculate. Good engineers communicate
- There are 3 kinds of people - language people, people people, object people
- When struggling to analyze a complex problem, shift your point of view from that of outside observer to that of the thing you are analyzing. If you were that thing, what forces would you feel? What internal stresses would you experience? How would you have to react to remain stable and not twist, turn, deform, be pushed over, or be caused to accelerate?
- Satisfaction = reward / input. When people feel fairly rewarded - when their ratio is at least as high as a peer's ratio - they are more likely to be motivated, under-rewarded leads to feeligns of distinterest and resentment, and over-rewarded may lead to feelings of guilt
- There's design behind the design - a well-designed product isn't well-designed if the process needed to manufacture it is unrealistic or uneconomical
- Engineering solutions must demonstrate objectively measurable improvement against a benchmark - bias is the difference between a predicted and actual value, variance the average distance between a set of data points and their mean value
- The most important thing is to keep the most important thing the most important thing - Donald Coduto. You must solve what you set out to do but don't become so focused on that one thing that you don't do as much as you can
- Sometimes the fix for an apparent engineering problem might not be an engineering fix - i.e., 66% of airplane accidents is caused by flight crew errors
- Engineering usually isn't inventing the wheel; it's improving the wheel
- The great continuum - engineering is undertaken within a continuum that connects profound human questions to ordinary activities. Engineers who work without awareness of the continuum will be inclined toward performing rote procedures. Those working in awareness of it will be better positioned to adapt to changing times, unexpected challenges, and unfamiliar circumstances. Those working across the continuum may be most apt to contribute something new.
What I got out of it
- Even if you're not an engineer, or should I say, especially if you're not an engineer, these principles and ways to think will be valuable to understand and apply. They hold true in business and in relationships