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The purpose of this paper is to evaluate and compare the effectiveness and sensitivity of different cleanliness verification tests for post soldered printed circuit board assemblies (PCBAs) to provide an understanding of current industry practice for ionic contamination detection limits.

PCBAs were subjected to different flux residue cleaning dwell times and cleanliness levels were verified with resistivity of solvent extract, critical cleanliness control (C3) test, and ion chromatography analyses to provide results capable of differentiating different sensitivity levels for each test.

This study provides an understanding of current industry practice for ionic contamination detection using verification tests with different detection sensitivity levels. Some of the available cleanliness monitoring systems, particularly at critical areas of circuitry that are prone to product failure and residue entrapment, may have been overlooked.

Only Sn/Pb, clean type flux residue was evaluated. Thus, the current study was not an all encompassing project that is representative of other chemistry‐based flux residues.

The paper provides a reference that can be used to determine the most suitable and effective verification test for the detection of ionic contamination on PCBAs.

Flux residue‐related problems have long existed in the industry. The findings presented in this paper give a basic understanding to PCBA manufacturers when they are trying to choose the most suitable and effective verification test for the detection of ionic contamination on their products. Hence, the negative impact of flux residue on the respective product's long‐term reliability and performance can be minimized and monitored effectively.

The use of an electroless nickel/immersion gold (ENIG) surface finish comes with the inherent potential risk of Black Pad failures that can cause fracture embrittlement at the interface between the solder and the metal pad. As yet, there is no conclusive agreed solution to effectively eliminate Black Pad failures. The case studies presented are intended to add to the understanding of the Black Pad failure mechanism and to identify both the plating and the subsequent assembly processes and conditions that can help to prevent the likelihood of Black Pad occurring.

Scanning electron microscope (SEM) analysis of exposed pad surfaces on failed PCBs demonstrated a “mud‐crack” appearance, which is a characteristic of the Black Pad phenomenon. In addition, energy dispersive X‐ray (EDX) analysis was used to identify the elemental composition of the fractured layer between the Ni₃P and Ni₃Sn₄ inter‐metallic compound, confirming the presence of Black Pad.

Grain boundaries or “mud‐cracks” that can be clearly seen in a top view of the failed pad surface and corrosion spikes in the failed pad surface, as evident from the cross‐section sample, should be used as a guideline to confirm Black Pad failures. Maintaining an optimum and well‐controlled EN and immersion gold bath, in addition to good process control prior to nickel‐gold deposition is recommended as the best approach for minimizing the occurrence of Black Pad failures.

Only Sn/Pb soldering processes using ENIG PCBs or package substrates were evaluated and discussed. Thus, the current case studies do not encompass Black Pad failures with lead‐free soldering.

The work reported provides guidelines that can be used to identify Black Pad occurrence. It also proposes relevant approaches for minimizing the possible occurrence of Black Pad.

The findings of these studies provide a basic understanding of the Black Pad failure mechanism. Subsequently, both the plating and the ensuing assembly processes and conditions that can help to prevent the likelihood of Black Pad occurrence were identified.

Both Hong Kong and Singapore leverage teacher collaboration to improve student learning, but state reforms differ in how teacher collaborative capabilities are prioritized. This paper provides a nuanced comparison of Hong Kong and Singapore teachers' values (risk-taking, power distance and uncertainty avoidance) to develop insights into how different policy focuses cultivate teachers' capabilities to focus on improving student learning.

Employing Hargreaves and Fullan's (2012) concept of professional capital, statistical analyses determine teachers' values profiles of high, medium and low professional capital in the respective contexts. Leveraging related research on Singapore teachers (Lee and Lee, 2018), nuances in teachers' values in the Hong Kong results are identified via cluster analysis and explained via structural equation modelling.

Medium professional capital Hong Kong teachers' values matched Singapore's, but teachers in other clusters are nuanced. Compared to Singapore teachers with similar levels of professional capital, high professional capital Hong Kong teachers have higher uncertainty avoidance, while low professional capital teachers are the opposite. In Hong Kong, high uncertainty avoidance values positively influence teacher leadership and focus on student learning. Nevertheless, as with their Singapore counterparts, high professional capital Hong Kong teachers have low power distance and high risk-taking values.

This paper raises awareness regarding policy's influence in cultivating teachers' values and their transformational change capabilities. By comparing two hierarchical Chinese societies, the discussion questions whether Chinese and Western cultural influences are mutually exclusive, and whether transformational change in cultural values, if achievable, is necessary.

Behavioral intention models are assumed to be universally applicable; however, recent criticisms have questioned their application among non‐Western subjects. It is argued that models that posit constructs that represent and measure the cultural nature of evaluative and normative latent constructs will best model intention formation in a culture. Thus, emic measures of etic latent constructs are required. A review of culturally‐influenced differences in reasoning processes between Chinese and Americans provides a theoretical basis to explore these models with samples from two cultures. Models considered Western, Oriental, and universal were compared with Hong Kong and US subjects. As predicted, the most Western model fit the USA data best and the most Oriental model fit the Hong Kong data best. Also as predicted, the measures of evaluation most representative of emic thought processes were most related to intention formation. Results suggest that the BI framework is applicable across cultures, yet must be operationalized with the distinctive thought processes of each culture in mind.

This paper aims to explore one question: to what extent does urban rehabilitation impact the housing search cost of the low-income tenants.

This paper adopts the fixed effects time-on-market (TOM) model and pricing model to study the research question.

Urban rehabilitation lifts the subdivided units (SDUs’) prices by around 7%. For the SDU located in old districts, urban rehabilitation gives rise to the rental price up by 11%–12%. The SDUs in the area without urban rehabilitation experience a short marketing period of 16%–17%. The SDU located in the old district that is without urban rehabilitation would have a short marketing time.

To the best of the authors’ knowledge, this is the pioneering research to investigate the relationship between rehabilitation and low-income rental housing from the improved search theory. The improved search theory posits that under the circumstance of urban rehabilitation, low-income tenants’ options are limited and the search behavior will be restricted in the affordable areas, and then TOM will be shortened. With the concentration of SDUs in Hong Kong, the test of the search theory is broken down into two hypotheses. (H1) Urban rehabilitation leads to low-income housing prices increase. (H2) Low-income housing located in areas without urban rehabilitation has a shorter TOM.

This study aims to investigate the cointegration and causality relationships between Hong Kong’s residential property price and stock price, using quarterly data, from the 1st quarter of 1980 to the 3rd quarter of 2015.

In contrast to other studies, the cointegration test used is the autoregressive distributed lag (ARDL) cointegration (bounds testing) approach of Pesaran et al. (2001) that based on the estimation of an unrestricted error correction model and the causality test is based on non-causality test of Granger et al. (2000). Moreover, this research employs recursive least square procedures and Chow (1960) breakpoint test to detect unknown structural break and variation of relationships between residential property and stock price over the whole sample period.

The results of ARDL cointegration tests running from stock to residential property markets provide strong evidence to support the hypothesis that the stock and residential properties are cointegrated. The results of Granger et al. (2000) non-causality test support the view of wealth effect that stock price has an important causal effect on residential property price in Hong Kong but not vice versa. In addition, the results of recursive ordinary least squares coefficients estimates and Chow (1960) test (breakpoint test) for structural instability confirm the variation of the relationships between stock and residential property markets over the sample period.

The empirical results from cointegration and causality tests suggest that the residential asset returns are better predicted by including the lagged difference values of stock price.

This is the pioneering study to examine the cointegration and causality study of stock and residential property price in Hong Kong by employing Pesaran ARDL cointegration approach and Granger non-causality approach. Investors are able to perform an effective evaluation to assist in allocating investment funds, and the government bodies can implement supplement housing policy in response to the public needs.

The purpose of this paper is to explore how principals’ leadership approaches to teacher professional development arise from school banding and may impact upon teacher professional capital and student achievement.

The case study is situated within the context of school-based management, comprising reflective accounts of nine school principals selected by stratified sampling from a sample of 56 Hong Kong schools to represent Bands One, Two, and Three schools. The reflective accounts were triangulated with observations of teachers and analysis of school websites.

First, under school-based management, principals remain obliged to recognize the power of state-defined examinations in determining the schools’ future priorities. Second, the exercise of school autonomy in response to this obligation varies, depending upon the competitive advantage schools have in the school banding system. Ideally, effective school-based management is dependent upon the principal’s capacity to facilitate good instructional practices. However, principals need to adjust their leadership practices to school contextual demands. Third, adaptations to contexts result in the varied developments of teacher capacities in schools, corresponding with the types of principal leadership adopted.

While statistical studies have identified attributes of exemplary principal leadership, few studies have examined the qualitative reasons for the exemplification of these attributes, and the influence of the school context in shaping these attributes. Departing from assumptions that leadership attributes are intrinsic to individuals, this paper considers how principals contextualize leadership in teacher professional development to the schools’ student academic achievement.

This paper aims to examine why retail firms seldom achieve full integration of online and offline channels as prescribed in omni-channel literature. It examines the intermediate process of channel integration from an internal, operational perspective.

This study is composed of two parts. In the first part, the authors interviewed informants from nine firms that were engaged in channel integration. In the second part, the authors conducted case studies with three firms from the cosmetics and skincare industry against the backdrop of the COVID-19 pandemic to find evidence to support or negate the propositions made in the first part.

The first part identified six operational challenges to channel integration. The authors categorized these challenges into two groups: inter-channel communication and inter-channel competition. Inter-channel competition carries more weight at the latter stage of integration. The authors also identified two antecedents that affect the seriousness of these challenges: heterogeneity among channels in business operation and external competitive pressure. In the second part, the authors found that both inter-channel communication and inter-channel competition were improved because of the external competitive pressure exerted by the COVID-19 pandemic. However, the heterogeneity of offline channels against online channels in business operation is a double-edged sword.

The study identifies the changing effects of the challenges of channel integration and their antecedents in the midst of integration. The positive influence of a specific dimension of channel heterogeneity against other channels increases and then decreases along channel integration. The identification of the changing effects lays the foundation for a finer stage model of channel integration.

The increasing consciousness of environmental protection has fostered the development of environmental management systems (EMS). ISO 14001 is an international standard that provides guidance for the establishment and monitoring of EMS implementation. Investigates the development of environmentally‐friendly construction operations based on a recent study in Hong Kong. Contributes to identifying the elements and processes of EMS implementation, and explaining the procedural guideline of a seven‐step EMS approach in managing construction practice. Incorporating the compliance requirements of ISO 14001, the approach addresses the policy, the implementation and monitoring, and continuous improvement of construction operations. The tangible and intangible benefits of the approach are also discussed with reference to the experiences of the Housing Department in Hong Kong. The approach may also be useful for construction practitioners to manage the EMS processes and assess their environmental performance towards continuous improvement.