Container Terminal Operations and Logistics

Comprehensive practice flashcards covering container terminal logistics, quay and yard crane scheduling, transporter systems (AGV/ALV), and operational optimization models based on lecture transcripts.

According to Container Terminal Foresight 2020, what was the estimated world container throughput in 2020 compared to 1996?

The estimated throughput was $985\,million$ TEU in 2020 compared to $117\,million$ TEU in 1996.

What are the two types of block layouts in a container terminal as described in the lecture?

Container terminal blocks are laid out either parallel or perpendicular to the quay.

In an indirect transfer system, what is the sequence of container movement from a ship to storage?

The sequence is: SHIP $\rightarrow$ QUAY CRANE (QC) $\rightarrow$ YARD CRANE (YC) $\rightarrow$ GROUND $\rightarrow$ YARD CRANE $\rightarrow$ TRUCK STORAGE.

What is the specific feature of an On-chassis System (Direct transfer system) as seen in the Auckland port in California?

The container moves directly from the SHIP to the QC, then onto a Chassis and Tractor, and finally to storage.

What are the three levels of multi-lifting mentioned for Quay Cranes?

Single lifting, Tandem lifting, and Triple lifting.

What is the functional difference between an Automated Guided Vehicle (AGV) and an Automated Lifting Vehicle (ALV) in terms of handover?

The AGV requires synchronized handover (waiting for the crane), while the ALV allows non-synchronized handover, resulting in lower time loss.

Which yard crane type provides the highest storage capacity ($TEU/ha$) according to PEMA, and what is its value?

The end-loaded Automated Stacking Crane (ASC) (1 over 5) with a Shuttle carrier transporter, providing $1400\,TEU/ha$.

What is the formula for the number of gate lanes required, and how is it rounded?

$\text{No. of gate lanes} = \text{ROUNDUP}[\frac{\text{Total dispatch time}}{3600}]$.

What does the probability density function (PDF) $f(z)$ for the travel distance $Z$ represent in the context of gantry travel when $Z = |X_1 - X_2|$?

$f(z) = \frac{2(q-z)}{q^2}$ where $q$ is the shape factor.

How is the expected number of handlings ($hc(t)$) to retrieve a container on the $t^{th}$ tier calculated using a gantry crane?

$hc(t) = T - t + 1$, where $T$ is the maximum number of tiers.

In flexible retrieval of a single container, what is the formula for the probability $P(t)$ that a container in the requested group is on the $t^{th}$ tier?

$P(t) = \frac{(1-p)^{S(T-t)} (1 - (1-p)^{S})}{1 - (1-p)^{ST}}$, where $p$ is the proportion of the requested group and $S$ is the number of stacks.

What are the primary objectives of the Berth Planning Problem?

(1) Minimize total weighted tardiness of vessels, (2) Minimize total flow time, and (3) Minimize delivery distance between berthing position and storage positions.

Define the LPT (Longest Processing Time) and SPT (Shortest Processing Time) rules as they apply to Berth Allocation.

The LPT rule is a heuristic used for minimizing make-span, while the SPT rule provides the optimal solution for minimizing total flow time.

In the mathematical model for continuous berth scheduling, what do the decision variables $x_i$ and $y_i$ represent?

$x_i$ represents the berthing position of vessel $i$, and $y_i$ represents the berthing time of vessel $i$.

What is the precedence constraint in QC work scheduling regarding deck and hold operations during discharging?

Tasks on the deck must be performed before tasks in the hold of the same ship-bay are performed.

What are the five main yard management principles for storing containers?

(1) Nearest Location Principle, (2) Least Congestion Principle, (3) Categorization Principle, (4) Minimum Relocation Principle, and (5) Minimum Broken-spaces Principle.

In the simulation study of yard storage rules, what does 'RSBLOCK' stand for?

Role Separation of Block.

Describe the difference between Container Relocation Problem (CRP) and Container Reshuffling Problem (CPMP).

CRP determines the next container to retrieve and where to put relocated ones to satisfy retrieval, while CPMP (pre-marshaling) attempts to relocate containers before trucks arrive so no rehandling occurs during retrieval.

What is the 'Deadlock-free reservation scheduling algorithm' used for in AGV routing?

It uses a 'grid priority table' ($+1$ or $-1$) to ensure that new reservation schedules are consistent with previous ones to prevent circular wait/deadlocks.

According to the yard crane scheduling rules, what is the 'UT' rule?

Uni-directional Travel: A yard crane travels in one direction serving all trucks until no more remain in that direction, then reverses.

In Reinforcement Learning for yard scheduling, how is the Q-function update rule represented?

$\hat{Q}(s,a) \leftarrow f + \gamma \min_{a'} \hat{Q}(s', a')$ where $f$ is the immediate penalty and $\gamma$ is the discounting factor.

What are the three types of remarshaling based on spatial range?

Intra-bay remarshaling, intra-block remarshaling, and inter-block remarshaling.

In storage space usage planning, what is the objective of the tactical decision-making problem?

To minimize the total transportation, storage, and handling costs of containers across multiple yards.