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A low cost multichip module employing solder bumped flip chips mounted on an organic substrate was demonstrated. This functional prototype was used to help assess the preliminary feasibility of low temperature solder bumped flip chip applications, from wafer design, sourcing and bumping, substrate design and fabrication, to MCM‐L assembly.

A no‐clean mass reflow process for 396‐pin, 324‐pin and 225‐pin over moulded plastic pad array carriers (OMPACs) or plastic ball grid array (BGA) is presented. Emphasis is placed on the OMPAC assembly parameters such as the design, material and process of the packages and printed circuit board (PCB), solder paste, stencil design, printing technology, pick and place, mass re‐flow and inspection. Furthermore, cross‐sections and the ‘popcorn’ effect of the OMPAC assembly are provided and discussed.

The mechanical and vibration responses of 225‐pin, 324‐pin and 396‐pin PBGA (plastic ball grid array) solder joints have been determined in this study. The effects of overload environmental stress factors on the mechanical responses of the solder joints have been determined by bending and twisting experiments. The effects of shipping and functional environmental stress factors on the vibration responses of the solder joints have been determined by out‐of‐plane vibration experiments and a mathematical analysis.

A two‐dimensional numerical computer simulation based on the analysis of the first three moments of the Boltzmann equation, known as the energy‐transport model, has been used to study various two‐dimensional effects on the performance of AlGaAs/GaAs heterostructure field‐effect transistor. The results are presented for half‐micron gate length. The calculation reveals significant electron current contribution coming from the AlGaAs region between the source and gate, contributing to the reduction of access resistance. As the electrons acquire large energies near the drain side edge of the gate, real‐space transfer to the AlGaAs region from the “two‐dimensional” electron gas channel occurs. However, at the drain end, the electron current is confined at the GaAs side of the heterointerface. The result shows insignificant current contribution from regions of depth greater than 0.048 µm into the undoped GaAs bulk. At room temperature, the results indicate transconductance, current gain cutoff frequency and power density about twice that which are calculated for “equivalent” GaAs MESFET, of identical structure and doping level as the heavily‐doped AlGaAs region. These results suggest that HEMT devices have the potential for providing significant sources of power at millimeter‐wave frequencies.

Geotechnical fills are used for building roadway embankments, filling in behind retaining walls, and as backfill above buried pipelines. Lightweight fill reduces the load so structures can be built more economically. A new lightweight geo‐material made from recycled plastic bottles glued together in their original post‐consumer form was developed. The purpose of this work is to explore the use of this new material as a lightweight geotechnical fill.

Through a preliminary laboratory and field study, aspects of the physical and mechanical characteristics of the recycled plastic bottle blocks were investigated. This new material is currently undergoing field trials behind a retaining wall on a bicycle path.

It was found that the average density of this new material is very low, at 32.63 kg/m³ (2.04 lb/ft³), with 59.5 percent of a block made up of recycled plastic bottles. The plastic bottle waste stream obtained from a recycling plant is gap‐graded having approximately 25 percent of the bottle volume at the 2 l bottle size with the remaining 75 percent at the 500 ml bottle size. Unconfined compression tests on small ten‐bottle samples produced strengths of 60 kN/m² (1,250 lb/ft²).

Testing indicates that this material may be useful as a lightweight geotechnical fill over soft soils or behind retaining walls; as an energy‐absorbing crash barrier for highway, race track, or airport safety; as ground and building insulation for Arctic construction; as floating barriers or platforms for offshore work; or for acoustic or vibration dampening for manufacturing processes.

This work explores the use of large volumes of recycled plastic bottles as an environmentally friendly geotechnical engineering material. Engineering parameters for this new material are presented as well as a discussion of an ongoing field study. The information presented here is the first step in understanding this new material with respect to civil engineering applications.

The purpose of this study is to present a highly stretchable and flexible strain sensor with simple and low cost of fabrication process and excellent dynamic characteristics, which make it suitable for human motion monitoring under large strain and high frequency.

The strain sensor was fabricated using the rubber/latex polymer as elastic carrier and single-walled carbon nanotubes (SWCNTs)/carbon black (CB) as a synergistic conductive network. The rubber/latex polymer was pre-treated in naphtha and then soaked in SWCNTs/CB/silicon rubber composite solution. The strain sensing and other performance of the sensor were measured and human motion tracking applications were tried.

These strain sensors based on aforementioned materials display high stretchability (500 per cent), excellent flexibility, fast response (approximately 45 ms), low creep (3.1 per cent at 100 per cent strain), temperature and humidity independence, superior stability and reproducibility during approximately 5,000 stretch/release cycles. Furthermore, the authors used these composites as human motion sensors, effectively monitoring joint motion, indicating that the stretchable strain sensor based on the rubber/latex polymer and the synergetic effects of mixed SWCNTs and CB could have promising applications in flexible and wearable devices for human motion tracking.

This paper presents a low-cost and a new type of strain sensor with excellent performance that can open up new fields of applications in flexible, stretchable and wearable electronics, especially in human motion tracking applications where very large strain should be accommodated by the strain sensor.

This study aims to evaluate and summarize the effectiveness of cognitive behavioral therapy (CBT) and internet-based CBT (ICBT) interventions on relapse prevention and severity of symptoms among individuals with major depressive disorder (MDD). CBT is one of the most used and suggested interventions to manage MDD, whereas ICBT is a novel effective proposed approach.

The review was conducted following the preferred reporting items for systematic review and meta-analysis protocol. A comprehensive and extensive search was performed to identify and evaluate the relevant studies about the effectiveness of CBT and ICBT on relapse prevention and severity of symptoms among patients with MDD.

A total of eight research studies met the inclusion criteria and were included in this systematic review. RCT studies were conducted to assess and evaluate the effectiveness of CBT and ICBT on relapse prevention and severity of symptoms among patients with MDD. It has been found that CBT is a well-supported and evidently based effective psychotherapy for managing depressive symptoms and reducing the relapse and readmission rate among patients diagnosed with MDD. The ICBT demonstrated greater improvements in depressive symptoms during major depressive episodes among patients with MDDS. The ICBT program had good acceptability and satisfaction among participants in different countries.

Despite the significant findings from this systematic review, certain limitations should be acknowledged. First, it is important to note that all the studies included in this review were exclusively conducted in the English language, potentially limiting the generalizability of the findings to non-English speaking populations. Second, the number of research studies incorporated in this systematic review was relatively limited, which may have resulted in a narrower scope of analysis. Finally, a few studies within the selected research had small sample sizes, which could potentially impact the precision and reliability of the overall conclusions drawn from this review. The authors recommend that nurses working in psychiatric units should use CBT interventions with patients with MDD.

This paper, a review of the literature gives an overview of CBT and ICBT interventions to reduce the severity of depressive symptoms and prevent patients’ relapse and rehospitalization and shows that CBT interventions are effective on relapse prevention among patients with MDD. In addition, there is still no standardized protocol to apply the CBT intervention in the scope of reducing the severity of depressive symptoms and preventing depression relapse among patients with major depressive disorder. Further research is needed to confirm the findings of this review. Future research is also needed to find out the most effective form and contents of CBT and ICBT interventions for MDD.

CBT is a psychological intervention that has been recommended by the literature for the treatment of major depressive disorder (MDD). It is a widely recognized and accepted approach that combines cognitive and behavioral techniques to assist individuals overcome their depressive symptoms and improve their overall mental well-being. This would speculate that effectiveness associated with several aspects and combinations of different approaches in CBT interventions and the impact of different delivery models are essential for clinical practice and appropriate selection of the interventional combinations.

This systematic review focuses on the various studies that explore the effectiveness of face-to-face CBT and ICBT in reducing depressive symptoms among patients with major depressive disorder. These studies were conducted in different countries such as Iran, Australia, Pennsylvania and the USA.

The purpose of this article is to attempt to highlight various approaches for enhancing the viability of probiotics, with special emphasis on micro‐encapsulation.

Various techniques, such as selection of acid and bile resistant strains, use of oxygen impermeable packaging materials, two‐step fermentation, stress adaptation, inclusion of micro‐nutrient, sonication of bacteria and micro‐encapsulation, which could be employed for maintaining or enhancing probiotic viability are discussed, with special emphasis on micro‐encapsulation.

Probiotics lose their viability during gastro‐intestinal transit due to unfavorable intestinal environment. Amongst diverse techniques micro‐encapsulation could confer protection to the probiotics both in the product as well as in the gastro‐intestinal environment.

The paper shows that micro‐encapsulation of probiotics renders them stable both in the product as well as in the intestinal environment and application of encapsulated probiotics would result in a product with greater prophylactic activities.

This paper aims to illustrate the importance of the quality of Online Learning Physical Environment (OLPE) and Online Learning Self-efficacy (OLSE) in predicting academic performance in online learning, which was the primary mode of teaching during the outbreak of COVID-19 in Hong Kong. Policy recommendations were made based on the findings from a psychological perspective.

Responses from 104 Hong Kong undergraduate students were collected through a questionnaire survey. Data were analysed using multiple linear regression, simple linear regression, and Pearson correlation.

Despite the fact that OLSE showed no significant direct effect on academic performance in online learning, OLSE was positively correlated with and predictive of OLPE, while OLPE was positively correlated with and predictive of online learning performance. The findings indicated that undergraduate students from low-income families tended to have less superior academic performance, which was associated with poorer OLPE and OLSE.

The findings suggested that in order to alleviate learning inequality in online learning, policy makers may allocate funding to enhance OLPE and OLSE of undergraduate students from low-income families.

The purpose of this paper is to describe how librarians used elements of market research, advertising and media literacy in a personal finance class.

Librarians each semester guest lecture one session in a personal finance class “Foundations of Money Education.” Through this class, librarians present engaging material about market research and advertising in an effort to encourage students to think about how these external forces influence their spending behavior.

Students appreciate learning about advertising through the engaging use of commercials. While responses were mixed as to the applicability of the topic, the majority of students agreed that the topic was a worthwhile addition to the personal finance curriculum.

Topics such as budgets, savings, and mortgages are typically taught in personal finance classes. Teaching information about market research and advertising is a topic that is usually not covered in a personal finance class.