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In the first paper of this two-part series, the assembly variant design system architecture and complementary assembly methodology have been presented. The general complementary assembly models, hierarchical assembly model and relational assembly model, are established which were further specified as assembly variants model (AVM) and assembly mating graphs (AMG) respectively to cater for the needs for assembly variant design. This paper discusses the assembly variant design methodology which is based on these assembly models. The matching components are searched and retrieved from the AVM and then the constraint groups are identified by manipulating the AMGs. Then the assembly variant design process is formulated as a mixed integer (linear or nonlinear) programming problem which is solved using a standard solver or heuristic. This methodology provides a systematic approach to facilitate the variant design of complex assembly products in the agile manufacturing environment. Finally, a prototype system is developed and examples are presented.

In this contribution, a discrete-time single-server infinite-capacity queue with correlated arrivals and general service times is investigated. Arrivals of cells are modelled as an on/off source process with geometrically distributed on-periods and off-periods, which is called Bernoulli bursty source. Based on the probability generating function technique, closedform expression of some performance measures of system, such as average buffer content, unfinished work, cell delay and so on, are obtained. Finally, the effects of system parameters on performance measures are illustrated by some numerical examples.

We study the structural properties of Pakistan railway network (PRN), where railway stations are considered as nodes while edges are represented by trains directly linking two stations. The network displays small world properties and is assortative in nature. Based on betweenness and closeness centralities of the nodes, the most important cities are identified with respect to connectivity as this could help in identifying the potential congestion points in the network.

The structure and properties of public transportation networks have great implications in urban planning, public policies, and infectious disease control. This study contributes a weighted complex network analysis of travel routes on the national highway network of Pakistan. The network is responsible for handling 75 percent of the road traffic yet is largely inadequate, poor, and unreliable. The highway network displays small world properties and is assortative in nature. Based on the betweenness centrality of the nodes, the most important cities are identified as this could help in identifying the potential congestion points in the network. Keeping in view the strategic location of Pakistan, such a study is of practical importance and could provide opportunities for policy makers to improve the performance of the highway network.