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In recent years, cost overrun becomes a common problem in steel building construction projects. The average percentage can vary widely depending on the project type, size, complexity and location. The steel structure change ratio in Taiwan is from 1 to 18% in statistics. The contractors always put every possible effort into preventing or mitigating project cost overruns, and one of the approaches is an accurate cost overrun risk estimate. Traditional project cost overrun risk assessment models mainly focus on macro-level evaluation and may not function well for the project-specific level (micro-level). This study creates a network-like connection model between the outcome (i.e. cost overrun risk) and the associated root causes in which the project status evaluation checklists of design, manufacturing, construction and interfaces are used to evaluate the checklists' influences through the Bayesian network (BN) composed by intermediate causes.

Due to the constraint of data availability, BN nodes, relationships and conditional probabilities are defined to establish a BN-based steel building project cost overrun assessment model following the knowledge of experts. Because of the complexity of the BN, the construction of the BN structure is first to build BN's fault tree (FT) hierarchy. And then, basic BN framework is constructed by the transformation of the FT hierarchy. Furthermore, some worthwhile additional arcs among BN nodes are inserted if necessary. Furthermore, conditional probability tables (CPTs) among BN nodes are explored by experts following the concept of the ranked node. Finally, the BN-based model was validated against the final cost analysis reports of 15 steel building projects done in Taiwan and both were highly consistent. The overall BN-based model construction process consists of three steps: (1) FT construction and BN framework transformation, (2) CPT computation and (3) model validation.

This study established a network-like bridge model between the outcome (i.e. cost overrun risk) and the root causes in a network of which cost influences are evaluated through the project-specific status evaluation checklists of design, manufacturing, construction and interfaces. This study overcame several limitations of the previous cost overrun risk assessment models: (1) few past research support assessment of cost overrun based on real-time project-owned data and (2) the traditional causal models inadequately depict interdependencies among influence factors of cost overrun at the network. The main influence factors of the cost overrun risk at the steel building projects in Taiwan were also examined using sensitivity analysis. The main root causes of cost overrun in steel building projects are design management and interface integration.

The proposed model belongs to the project-specific causal assessment model using real-time project-owned status checklist data as input. Such a model was seldom surveyed in the past due to the complicated interdependence among causes in the network. For practical use, a convenient and simple regression equation was also developed to forecast the cost overrun risk of the steel building project based on the root causes as input. Based on the analysis of cost overrun risk and significant influence factors, proper tailor-made preventive strategies are established to reduce the occurrence of cost overrun at the project.

This paper aims to develop a dynamic civil facility degradation prediction model to forecast the reliability performance tendency and remaining useful life under imperfect maintenance based on the inspection records and the maintenance actions.

A real-time hidden Markov chain (HMM) model is proposed in this paper to predict the reliability performance tendency and remaining useful life under imperfect maintenance based on rare failure events. The model assumes a Poisson arrival pattern for facility failure events occurrence. HMM is further adopted to establish the transmission probabilities among stages. Finally, the simulation inference is conducted using Particle filter (PF) to estimate the most probable model parameters. Water seals at the spillway hydraulic gate in a Taiwan's reservoir are used to examine the appropriateness of the approach.

The results of defect probabilities tendency from the real-time HMM model are highly consistent with the real defect trend pattern of civil facilities. The proposed facility degradation prediction model can provide the maintenance division with early warning of potential failure to establish a proper proactive maintenance plan, even under the condition of rare defects.

This model is a new method of civil facility degradation prediction under imperfect maintenance, even with rare failure events. It overcomes several limitations of classical failure pattern prediction approaches and can reliably simulate the occurrence of rare defects under imperfect maintenance and the effect of inspection reliability caused by human error. Based on the degradation trend pattern prediction, effective maintenance management plans can be practically implemented to minimize the frequency of the occurrence and the consequence of civil facility failures.

The effects of thermal fatigue and printed circuit board (PCB) surface finish on the pull strength, failure modes and reliability of chip scale package (CSP) solder joints were investigated.

Mechanical pull test, metallographic examination and electrical measurement were used. Tin lead (Sn‐Pb) and lead free (Sn‐Ag‐Cu) alloys were used with Au/Ni and organic solderability preservative (OSP) surface finishes.

The experimental results showed that the pull strength of the Sn‐Ag‐Cu/(Au/Ni) solder joint did not change noticeably with an increasing number of thermal cycles. However, the pull strength of the Sn‐Pb/(Au/Ni) solder joints drastically degraded and that of the Sn‐Ag‐Cu/OSP and Sn‐Pb/OSP solder joints slightly decreased during thermal cycling. For both Sn‐Ag‐Cu and Sn‐Pb alloys, the solder joint fracture of as‐soldered samples was the main failure mode when an Au/Ni surface finish was used. For the Sn‐Ag‐Cu/(Au/Ni) and Sn‐Ag‐Cu/OSP solder joints, the proportion of component trace tearing considerably decreased, whereas that of PCB trace tearing considerably increased, during thermal cycling. The Weibull lifetimes of the solder joints were increasingly longer in the order of Sn‐Pb/(Au/Ni), Sn‐Pb/OSP, Sn‐Ag‐Cu/OSP, and Sn‐Ag‐Cu/(Au/Ni).

This was not an exhaustive study and all of the findings are for lead free and tin lead CSP solder joints, which perhaps limits the usefulness of the results elsewhere.

A very useful source of information and impartial advice for engineers planning to conduct a switch from tin lead to lead free technology in their production lines.

This paper fulfils an identified information/resources need and offers practical help to an engineer starting out on an engineering development.

Given the intense competition in the hotel industry, this study investigates the effect of overwork (OW) and overtime (OT) on turnover intention (TI) as well as the moderating effect of incentives in the context of non-luxury hotels in an emerging market.

Using a purposive sampling technique, a total of 271 front-line employees who are currently working in non-luxury hotels in Sarawak responded to the study. Partial least squares structural equation modeling (PLS-SEM) was used to perform latent variable and moderation analyses.

The findings show that both OW and OT have a direct impact on TI. Contrary to the past studies, incentives do not exert any moderating effect on the relationship between OW, OT and TI among the employees working at non-luxury hotels.

This is one of the first studies to explore the effect of incentives between OW and working OT on TI in the context of the non-luxury hotels in an emerging market and show why incentives might not work. It further advances the understanding of the JD-R theory, demonstrating the necessity for organizations to provide matching resources to address job strains.