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The purpose of this study is to deploy and expand the theory of planned behaviour (TPB) model with application to renewable energy investment by incorporating the component of tax incentives (TIN). This will serve as an additional measure in understanding the conventional energy stakeholders’ investment intention into renewable energy in Nigeria.

Data was collected from 357 individual key conventional energy stakeholders in Nigeria using survey questionnaires. The research model was tested using structural equation modelling.

The results from the study revealed the applicability of the TPB in predicting the conventional energy stakeholders’ investment intention into renewable energy. The result indicates that attitude and subjective norm are significantly associated with investment intentions.

The outcome implies that the integration of tax incentives can improve the predictive power of the model as the introduced variable demonstrates a significant impact on the conventional energy stakeholders’ investment intention into renewable energy.

This study extends on the well-established TPB model by integrating tax incentives in understanding investment intentions and the outcome implies a significant association of tax incentives with investment intention and moderated the influence of attitude and subjective norm over the conventional energy stakeholders’ investment intention.

TPB has been widely deployed and even extended to predict intention in numerous fields of study. Available literature presents the lack of such empirical research that focuses on investment in Nigeria and specifically regarding energy investment. The outcome highlighted the significant influence of tax incentives, thus the need for policymakers to suggest and implement various tax incentives to attract private investment into renewable energy for electricity generation that will consequently assist in achieving SDG-7 and mitigate climate change.

The purpose of this paper is to present the results from work on a project aimed at evaluating six different copper alloy substrates coated with pure tin for tin whisker growth. The influence of intermetallic growth between the copper alloy substrate and the tin‐plating on the growth of tin whiskers has been investigated.

The experiment consisted of six substrates of different alloys of copper, plated with bright tin including copper beryllium, cartridge brass, phosphor bronze, Cu‐Ni‐Si “7025” and Cu‐Ni‐Sn “spinodal”. The samples were mechanically stressed and then subjected to temperature humidity storage conditions for 1,000 h. These samples were then evaluated for tin whisker growth and intermetallic layer thickness.

Of the six samples five showed tin whisker growth. For these samples the intermetallic layer thickness has little effect on tin whisker growth. Sample with Cu‐Ni‐Sn “spinodal” alloy substrate showed very low whisker density and comparatively lower maximum whisker length than the other tested substrate material.

More samples per condition should be evaluated to bolster the conclusions. For the sample without tin whisker growth, holes on the surface of the plating were observed. The holes in the plating provide an opportunity for stress relaxation after the plating process. Since stress in the plating layer is low, tin whiskers are not formed on the sample surface.

The paper details the tin whisker growth on six tin plated copper substrate samples. The intermetallic layer thickness for each copper alloy substrate is calculated. The relationship between the intermetallic layer thickness and tin whisker growth for the six substrates are discussed.

Total quality management (TQM) has been a popular managerial topic since the 1980s. However, not too many organizations have successfully implemented it. This paper studies a successful TQM project implemented in a manufacturing company in the People's Republic of China. It reports the TQM implementation process, the benefits generated from the TQM project, the problems that arose from the adoption of TQM for the company, and the main factors for the eventual success of the project. This case study is a reference for managers and researchers who are interested in TQM or interested in the Chinese managerial environment in general.

To review the literatures, and to consider the latest results regarding the formation of tin pest in lead‐free solders and interconnections.

Previous work, over almost a century, on tin pest formation in tin and its alloy has been critically analysed. Samples of the new generation of lead‐free solders, which have experienced long term storage at −18 and −40°C, have been examined.

Tin pest has been observed in bulk samples of tin −0.5 (wt%) copper solder after exposure at −18°C although not at −40°C. Other lead‐free alloys (Sn‐3.5Ag, Sn‐3.8Cu‐0.7Cu and Sn‐Zn‐Bi) have been immune to date. Large‐scale model joints exhibit tin pest but actual joints may be resistant due to the limited free solder surface available and the constraint of intermetallic compounds and components.

The possibility of tin pest formation in joints remains. It seems that impurities are essential protection against it, but for long term applications there is no certainty that tin pest and joint deterioration will never occur.

The paper considers the various factors that may affect tin pest formation and demonstrates its existence in one of the more popular new lead‐free alloys.

The aim is to present temperature fatigue model constants for lead‐free tin‐silver‐copper solder derived from test data and demonstrate the validity of the model using published experimental results.

Temperature cycle fatigue life data were collected from a controlled set of tests using ceramic leadless chip carriers. Using a regression algorithm, temperature cycle fatigue model constants were derived from fatigue life data. The model was then applied to a variety of package formats including ball grid arrays, quad flatpack and thin small outline packages to determine the validity of the model and constants.

The temperature cycle fatigue life experimental data were found to be in good agreement with the model with the derived model constants for various package types. Using this model, engineers can determine acceleration factors between test and field temperature cycle conditions.

The technology has been used to ensure inner layer designs with nominal dimensions after the lamination stage. Further, development work should be undertaken to collate measured data from other parts of the PCB manufacturing process and model the material movement around all registration critical processes.

The paper details a temperature cycle fatigue life model and constants that allow engineers to predict field life expectancy and determine the acceleration factor between temperature cycle testing and field use conditions.

To evaluate the oxide formation characteristics of tin (Sn) as a function of conditioning treatment and define a conditioning methodology that rapidly produces a tin oxide thickness and oxide species morphology similar to those formed in ambient oxidation.

Electrochemical reduction analysis and scanning electron microscopy techniques were utilized to identify tin oxide species and oxide quantities on tin samples which were subjected to a variety of conditioning methodologies.

Tin oxide species were identified and oxide quantities measured. Comparisons of tin oxide species/quantities were completed for the different conditioning methodologies used and for other industry oxide investigations. The following conclusions were reached: all conditioning methodologies produced both SnO and SnO₂ tin oxide species; steam conditioning produced the thickest oxides; the conditioning methodologies investigated were found to produce oxide thicknesses similar to those formed under ambient conditions.

Further investigation would be beneficial using this study as a foundation. Additional conditioning methodologies and a larger selection of various tin surfaces would provide a future understanding of the impact of oxide species and thickness on solderability.

The electronics industry has attempted to “predict” a surface's susceptibility to oxidation by using accelerated conditioning techniques. An understanding of the formation of tin oxidation products created by accelerated conditioning techniques could be highly beneficial to the electronics industry. The standardization and use of a realistic accelerated conditioning technique would reduce testing cycle time, increase the predictability and consistency of test results, and lower testing costs.

This paper was incorporated into an original electronics manufacturer's solderability testing/analysis procedures, and the results are being utilized by the electronics industry solderability specification task groups/committees.

This paper describes work which has been conducted to estimate the magnitudes of thermal stresses developed in the solder joints of electronic components during service. Finite Element Analysis (FEA) has been employed to predict the level of stress and strain in computer simulations of joints and these predictions have been validated by experimental thermal cycling tests. Future work is outlined including the incorporation of microstructural features into the FEA models. The overall goal of this research is to predict the service lives of electronic components under various operating conditions, thus facilitating the introduction of novel components and materials.

Light Detection and Ranging (LiDAR) offers a fast and effective way to acquire DSM and extract ground objects such as building, trees and so on. However, it is difficult to extract sharp and precise building boundary from LiDAR data, because its ground sample distance (GSD) is often worse than that of high resolution image. Recently, fusion of LiDAR and high resolution image becomes a promising approach to extract precise boundary. To find the correct and precise boundary, the aim of this paper is to present a series of novel algorithms to improve the quality.

To find the correct and precise boundary, this paper presents a series of novel algorithms to improve the quality. At first, a progressive algorithm is presented to register LiDAR data and images; second, a modified adaptive TIN algorithm is presented to filter ground point, where a region growth method is applied in the adaptive TIN algorithm; third, a novel criterion based on the density, connectivity and distribution of point cluster is developed to distinguish trees point; fourth, a novel method based on the height difference between neighbor points is employed to extract coarse boundaries; at last, a knowledge based rule is put forward to identify correct building boundary from parallel edges.

Thorough experiments, it is conducted that: the registration results are accurate and reliable; filtered ground points has good quality, without missing or redundancy; all tree clusters bigger than one grid are detected, and points of walls and edges are eliminated with the new criterion; detected edges exactly locate at real building boundaries, and statistics show the detection correctness is 98 percent, and the detection completeness is 95 percent.

All results prove that precise boundary can be extracted with fusion of LiDAR and high resolution image.

This paper aims to present two Anand’s model parameter sets for the multilayer silver–tin (AgSn) transient liquid phase (TLP) foils.

The AgSn TLP test samples are manufactured using pre-defined optimized TLP bonding process parameters. Consequently, tensile and creep tests are conducted at various loading temperatures to generate stress–strain and creep data to accurately determine the elastic properties and two sets of Anand model creep coefficients. The resultant tensile- and creep-based constitutive models are subsequently used in extensive finite element simulations to precisely survey the mechanical response of the AgSn TLP bonds in power electronics due to different thermal loads.

The response of both models is thoroughly addressed in terms of stress–strain relationships, inelastic strain energy densities and equivalent plastic strains. The simulation results revealed that the testing conditions and parameters can significantly influence the values of the fitted Anand coefficients and consequently affect the resultant FEA-computed mechanical response of the TLP bonds. Therefore, this paper suggests that extreme care has to be taken when planning experiments for the estimation of creep parameters of the AgSn TLP joints.

In literature, there is no constitutive modeling data on the AgSn TLP bonds.