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The purpose of this paper is to discuss the possibility of using soldering process for the bonding of chip-on-flexible (COF) light-emitting diode (LED) packages to heat sinks. The common bonding materials are thermal conductive adhesives. For thermal performance and reliability concerns, Tin-Bismuth (SnBi) lead-free solder paste was used for the connection of the COF packages and the Cu heat sinks by a soldering process in this study. Meanwhile, the geometrical effect of the SnBi solder layer on the thermal performance was also investigated.

The effects of the bonding materials and the area of the solder layers on the thermal performance of the LED modules were investigated by finite element simulation and experimental tests.

The SnBi soldered modules show much lower thermal resistance at the bonding layers than the adhesive-bonded LED module. Vertical heat transfer from the LED chips to the heat sinks is the primary heat dissipation mode for the SnBi soldered modules. Thus, the LED module with local solder layer shows similar LED thermal performance with the full-area soldered module. Meanwhile, the local soldering process decreases the possibility to form randomly distributed defects such as the large area voids and residue flux in the solder layers.

The research is still in progress. Further studies mainly focus on the reliability of the samples with different bonding materials.

COF package is a new structure for LED packages. This study provides a comparison between SnBi solder and adhesive material on the thermal performance of the LED. Meanwhile, the authors optimized the geometrical design for the solder layer. The study provides a feasible bonding process for COF packages onto heat sinks.

This study provides a soldering process for the COF LED packages. The thermal performance of the LED light source was improved significantly by the new process.

This study aims to provide a flexible and cost-effective solution of 3D heterogeneous integration for applications such as micro-electro-mechanical system (MEMS) applications and smart sensor systems.

A novel 3D system-in-package (SiP) based on stacked silicon submount technology was successfully developed and well-demonstrated by the fabrication and assembly process of a selected smart lighting module.

The stacked module consists of multiple layers of silicon submounts which can be designed and fabricated in parallel. The bonding and interconnecting process is quite simple and does not require complicated equipment. The 3D stacking design offers higher silicon efficiency and miniaturized package form factor. The submount wafer can be assembled and tested at the wafer level, thus reducing the cost and improving the yield.

The embedding design presented in this paper is applicable for modules with limited number of passives. When it comes to cases with more passive devices, new process needs to be developed to achieve fast, inexpensive and reliable assembly.

The presented 3D SiP design is novel for applications such as smart lighting, Internet of Things, MEMS systems, etc.

At present the energy generation and distribution landscape is changing rapidly. The energy grid is becoming increasingly smart, relying on an information network for the purposes of monitoring and optimization. However, because of the particularly stringent regulatory and technical constraints posed by smart grids, it is not possible to use ordinary communication protocols. The purpose of this paper is to revisit such constraints, reviewing the various options available today to realize smart‐metering networks.

After describing the regulatory, technological and stakeholders' constraints, the authors provide a taxonomy of network technologies, discussing their suitability and weaknesses in the context of smart‐metering systems. The authors also give a snapshot of the current standardization panorama, identifying key differences among various geographical regions.

It is found that the field of smart‐metering networks still consists of a fragmented set of standards and solutions, leaving open a number of issues relating to the design and deployment of suitable systems.

This paper addresses the need to better understand state‐of‐the‐art and open issues in the fast‐evolving area of smart energy grids, with particular attention to the challenges faced by communication engineers.

Although the use of online technology has generated excitement over its potential to increase access to education, most existing research has focused on comparing online and in-person student performance. This study provides empirical evidence that semiprivate space at the family level affects students' access to online education.

Students from 1,565 low-income households in China were surveyed, and a multivariate logistic regression analysis was conducted on the hypothesized factors that affect access to online education at home.

The results show that the absence of computers, smartphones and broadband networks at home severely hinders children's access to online education, and even leads to their exclusion from it. Children with their fathers or paternal grandfathers as guardians have a lower probability of receiving online education at home. It was also found that the higher the education level of the head of the household, the more likely it is that children will receive online education at home.

This study is one of the first to examine online accessibility at the family level. It also demonstrates that the semiprivate space at the family level may limit opportunities for students who would otherwise pursue online education at home.

This article addresses Taiwanese public opinion on same-sex marriage, connecting it to the 2020 general election.

Original survey data are combined with analysis of the existing literature and 2020 election results.

Original survey data find that nearly one in five respondents have changed their views on same-sex marriage since its legalization, with most of those who have changed their views more opposed to legalization than before. However, this shift and its related support for the Kuomintang (KMT) do not appear to have influenced election results.

The results suggest that positions on same-sex marriage remain somewhat in flux, while the success of the pro-legalization Democratic Progressive Party (DPP) may lead to additional LGBT rights.

This combines original survey data with election results to analyze the effects of same-sex marriage legalization on the election outcome.

The purpose of this paper is to examine the relationship between financial literacy and entrepreneurial activities, and the moderating effects of industrial regulation in the relationship between financial literacy and entrepreneurship.

In this study, the role of financial literacy on entrepreneurial participation and performance is investigated through multi-sourced data from the Chinese Family Panel Studies with manually merged provincial and industrial data from 2014. Four hypotheses are tested based on Probit and Tobit models. Moreover, instrumental variable method and principal component analysis are applied to provide robustness checks.

The empirical results demonstrate that financial literacy has significantly positive effects on entrepreneurial participation, as well as on entrepreneurial performance. In addition, industrial regulation positively moderates the effects of financial literacy on entrepreneurial participation and performance, which indicates that financial literacy plays a more important role in promoting entrepreneurship in tightly regulated industries.

This study proposes and tests the effects of financial literacy on entrepreneurial activities, which fills an important gap in the literature. The results in this paper provide evidence that financial literacy has positive impacts in both the entry and operation stages of entrepreneurship. This evidence provides theoretical foundations for policy making in popularizing financial knowledge and supporting entrepreneurial activities. Moreover, this research further reveals the effects of industrial regulation in the context of China, suggesting that the government should be more effective in promoting administrative decentralization and reducing unnecessary interventions.

Anecdotal accounts of suicide among temporary low-wage migrant workers in the UAE are numerous, but unofficial and qualitative accounts remain unexplored. This study aims to examine how the socio-environmental context can lead some low-wage migrants, irrespective of their nationality or culture, to contemplate suicide for the first time after arriving in the host country.

The findings draw from ten months of qualitative fieldwork (2015–2016) and in-depth interviews conducted with 44 temporary migrant workers from sub-Saharan Africa and South Asia, earning in the lowest wage bracket in Dubai. The study used a non-probabilistic, purposive sampling approach to select participants. Three criteria drove eligibility: participants had to reside in the UAE, be non-national and earn Dh1500 (US$408) or less a month. Otherwise, diversity was sought in regard to nationality, occupation and employer.

Eight (18%) of the 44 study participants interviewed admitted to engaging in suicidal thoughts for the first time after arriving in the UAE. The findings suggest that for low-wage migrants working in certain socio-environmental contexts, the religious, gendered or other cultural or group characteristics or patterns that may be predictors of suicide in migrants’ country of origin may become secondary or possibly even irrelevant when one is forced to survive under conditions that by most objective standards would be deemed not only oppressive but extremely exploitative and abusive.

This study contributes to understandings of how the emotional and psychological well-being of temporary foreign low-wage migrant workers can be impacted by the socio-environmental context of the host country. It is a first step in understanding the intimate thoughts of low-wage migrant workers on the topic of suicidality, furthering our understanding of suicidal ideation and the factors that can contribute to it.