Fundamental Principles of Engineering Mechanics

Principle of Transmissibility: A force acting on a rigid body can be moved to any other point along its line of action without changing its external effect on the body. The magnitude and direction of the force remain the same during this shift. This principle is applicable only to rigid bodies and not when internal stresses or deformations are considered.

Varignon’s Theorem: The moment of a force about any point is equal to the sum of the moments of its components about the same point. In other words, if a force is resolved into components, the algebraic sum of the moments of these components about a point is equal to the moment of the original force about that point.

Parallelogram Law of Forces:

Git Commands and Concepts

Git key commands and concepts:

• add (stage changes)
• commit (with a message)
• head (most recent commit)
• branch (alternative history)
• checkout (enter/exit branch)
• merge (combine into master)
• stash (save without commit, -u for untracked files; latest stashes (0) at the top)
• pop (retrieve a stash)
• fork (copy code from the source into a repository)
• pull (pull remote changes and merge into master)
• revert (undo commits and create a new commit)
• log (history with most recent commits first, -p for patch details)
• rm (--cached to remove from staging)
• fetch (get changes from a remote repository to a local repository without merging them; useful for reviewing changes)
• pull (fetch + merge)
• rebase (create a clean/linear commit history by moving commits

Configuring Source Routing and Initializing Routes

To begin, we set the routing type to source routing and clear any existing routes from the design. We then calculate the shortest path for each demand based on the number of traversed links.

/* Set the routing type to source routing */
netPlan.setRoutingType(RoutingType.SOURCE_ROUTING);

/* Remove all the routes in the input design */
netPlan.removeAllRoutes();

/* Create one route for each demand, with the shortest path in number of traversed links */
for (Demand d : netPlan.getDemands()) {
    List<Link> shortestPath = GraphUtils.getShortestPath(netPlan.getNodes(), netPlan.getLinks(), d.getIngressNode(), d.getEgressNode(), null);
    if (shortestPath.isEmpty()) {
        throw new Net2PlanException(

Binding

Lifecycle Hooks

Pipes

Fixed-function Circuits

Fixed-function circuits. They are manufactured to implement a specified logic function that cannot be altered.

Programmable Logic

Programmable logic uses devices which are manufactured to be programmed and implement different logic functions (they are alterable).

SPLD, CPLD, FPGA

SPLD — Simple Programmable Logic Device. CPLD — Complex Programmable Logic Device. FPGA — Field Programmable Gate Array.

Common Programmable Array Combinations

• PROM / RAM (Programmable Read Only Memory / Random Access Memory) — also known as a LUT (look-up table).
• Fixed AND array and programmable OR array — FPLA / PLA (Fully Programmable Logic Array / Programmable Logic Array). Both arrays, AND and OR, are programmable.

Programming Links and

Structural Stability

Stability depends on the capacity of the support. Ensure that the system is a structure, not a mechanism. Structures become unstable due to inadequate external support or loading.

Determining Stability

To determine stability, imagine a rigid body in a 2D coordinate system where each point is able to translate and rotate. We calculate the degree of freedom (DOF) using the following formula:

DOF = 3Rb - R - 2H

Conditions for Structural Instability

• Parallel reactions
• Concurrent forces

Influence Lines (IL)

An Influence Line (IL) is a graphic representation of the relationship between a component force, restraint reaction, or displacement value and the position of a unit force. There are two primary methods for development: the equilibrium... Continue reading "Structural Stability and Influence Lines Analysis" »

Binding Constraint: LHS equals to RHS at optimal ;  Non-binding constraint: LHS is not equal to RHS at optimal

Shadow Price: Amount by which OFV changes if RHS is increased by one unit

Basic Variable: A decision variable which has non-zero value at optimal ;  Non-basic Value: A decision variable which has a value of zero at optimal

Reduced cost: Amount by which the objective function coefficient needs to be decreased before the variable becomes basic

• Basic var: "Final Value" >0 and "Reduced cost"=0; With allow inc/dec, optimal solution (Final Value) doesn't change, OFV change by (change)*(Final Value); Beyond allow inc/dec, optimal solution and OFV changes by RESOLVE.
• Non basic var:  "Final Value"=0 and "Reduced cost"≠0; In a MIN,"Reduced

Digital Registers

As a flip-flop (FF) can store only one bit of data (a 0 or a 1), it is referred to as a single-bit register. A register is a set of FFs used to store binary data. The storage capacity of a register is the number of bits (1s and 0s) of digital data it can retain.

Loading a Register

Loading a register means setting or resetting the individual FFs—inputting data into the register so that their states correspond to the bits of data to be stored. Loading may be serial or parallel:

• Serial loading: Data is transferred into the register in serial form, i.e., one bit at a time.
• Parallel loading: Data is transferred into the register in parallel form, meaning all the FFs are triggered into their new states at the same time.

Types of Registers

1. Buffer

Port Sizing: Key Factors

Physical Factors

1. Oceanographic and Meteorological Conditions

These conditions define navigational restrictions. Wind conditions are classified as:

• Soft: Up to 36 kph
• Moderate: 36 - 63 kph
• Severe: 63 - 108 kph

2. Vessel Dimensions

Design vessel dimensions (LOA, breadth, freeboard, draft) are crucial for port design.

3. Vessel Maneuverability

• High: Light war vessels, cruises, bulk carriers, Ro-Ro vessels, first-generation containerships
• Medium: Modern war vessels, oil carriers (T-2), bulk carriers, second-generation containerships
• Low: Aircraft carriers, VLCC tankers, third and fourth-generation containerships, older or damaged vessels

4. Vessel Squat

Two main effects:

• Vertical movement (sinking)
• Longitudinal rotation

5. Vessel Movements

Tide... Continue reading "Port Sizing and Operations: Key Factors and Considerations" »