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The complexity of microelectronic circuits, their scale of integration and clock speed requirements have been increasing steadily. All these changes have the effect of increasing the power density of the microcircuits. ICs with a power of several watts and an area of over a square centimetre are quite common. Thus, there is more heat generated per device at die, component and substrate‐attach levels of electronic packaging. In order to maintain reliability of finished products, the junction temperature of the constituent devices must be kept low. It has been demonstrated that thermal management can be one key to lowering the cost and increasing the performance life of microelectronic products. The cost‐effectiveness of lowering device temperature has been demonstrated to be dramatic compared with the cost of thermal management materials. Proper thermal management of advanced microelectronic devices has to be addressed at all levels. One should address the problem from the basic level of die‐attach, through component‐attach, and eventually substrate‐attach to thermal drains. Thermal management is almost invariably coupled with a thermally induced stress problem. The increase in temperature at the device level also means a larger fluctuation of temperature from the ambient. Each cycle of on‐off for the device represents one thermal cycle. Stress‐induced failure due to coefficient of thermal expansion (CTE) mismatch is much more acute for higher power devices. In this paper, the authors address the issue of thermally induced stress on the microelectronic product at all levels of packaging, with major emphasis on component and substrate levels. Various ways and examples of reducing or eliminating this stress, which is a major cause of device failures, will be demonstrated. One of the proven methods is through the use of low Tg epoxies with high thermal stability.

Increasing power densities within electronic equipment have led to a rise in the number of heat related problems being experienced. This paper describes the use of computerised thermal analysis techniques to optimise the design of passive thermal management systems for electronic equipment.

Improper evaluation and information mismanagement concerning thermal comfort appears to negatively affect occupants' satisfaction and building energy consumption in precast concrete (PC) building contexts. Predictive models are particularly problematic in PC building construction projects where natural ventilation levels do not coincide with occupants' thermal comfort and thermal sensation specifications.

A systematic literature review is undertaken to explore the viability and benefits of a new ICT-based approach for meeting social and environmental objectives.

Sophisticated thermal comfort system solutions are essential for optimising thermal comfort and saving energy in PC building construction projects.

It is imperative that designers and manufacturers are kept up-to-date with the possibilities and potentials associated with new and nascent technologies so that building projects can meet key sustainability criteria.

Thermal management of high-power (HP) light-emitting diodes (LEDs) is an essential issue. Junction temperature (T_J) and thermal resistance (R_th) are critical parameters in evaluating LEDs thermal management and reliability. The purpose of this paper is to study thermal and optical characteristics of ThinGaN (UX:3) white LED mounted on SinkPAD by three types of solder paste (SP): No-Clean SAC305 (SP1), Water-Washable SAC305 (SP2) and No-Clean Sn42/Bi57.6/Ag0.4 (SP3).

Thermal transient tester (T3Ster) machine is used to determine T_J and total thermal resistance (R_th–JA). In addition, the LED’s optical properties are measured via thermal and radiometric characterization of power LEDs (TeraLED) system. The LED is mounted on SinkPAD using SP1, SP2 and SP3 by stencil printing to control a thickness of SP and reflow soldering oven to minimize the number of voids. The LED with SP1, SP2 and SP3 is tested at various input currents and ambient temperatures.

The results indicate that at high input current, which equals to 1,200 mA, R_th–JA and T_J, respectively, are reduced by 30 and 17 per cent between SP1 and SP2. At same current value, R_th–JA and T_J are minimized by 42 and 25 per cent between SP1 and SP3, respectively. In addition, at an ambient temperature of 85°C, R_th–JA and T_J are decreased by 34 and 7 per cent between SP1 and SP2, respectively. Similarly, the reduction in R_th–JA and T_J between SP1 and SP3 is 44 and 10 per cent, respectively. Luminous flux, luminous efficacy and color shift of the LED with the three types of SPs are compared and discussed. It is found that the SP1 improves the chromatic properties of the LED by increasing the overall light efficiency and decreasing the color shift.

Thermal and optical performance of ThinGaN LEDs mounted on SinkPAD via three types of SPs is compared. This investigation can assist the research on thermal management of HP ThinGaN-based LEDs.

The essential properties of active sports fabrics are moisture management, quick-drying, body heat management and thermal regulations. Fibre type, blending nature, yarn and fabric structure and the finishing treatment are the key parameters that influenced the performance of the clothing meant for sportswear. This study aims to investigate the effect of fibre blending and structural tightness factors on bi-layer sport fabric's dimensional, moisture management and thermal properties.

In this study, 12 different bi-layer inter-lock fabrics were produced. Polyester filament (120 Denier) yarn was fed to form the backside of the fabric, and the face side was varied with cotton, modal, wool and soya spun yarns of 30sNe. Three different types of structural tightness factors were considered, such as low, medium and high were taken for sample development. The assessment towards dimensional, moisture management and thermal properties was carried out on all the samples.

The polyester-modal blend with a high tightness factor has shown maximum overall moisture management capability (OMMC) values of 0.73 and air permeability of 205.3 cm³/cm²/s. The same sample has shown comparatively higher thermal conductivity of 61.72 × 10^–3 W m^-1 °C^-1(Under compression state) and 58.45 × 10^–3 W m^-1 °C^-1 (under recovery state). In the case of surface roughness is concerned, polyester-modal blends have shown the lowest surface roughness, surface roughness amplitude and surface friction co-efficient. Among the selected fibre combinations, the overall comfort level of polyester-modal bi-layer knitted structure with a higher tightness factor is appreciable. Polyester-modal is more suitable for active sportswear among the four fiber blend combinations.

The outcome of this study will help to gain a better understanding of fibre blends, structural tightness factor and other process specifications for the development of bi-layer fabric for active sportswear applications. The dynamic functional testing methods (Moisture management and Thermal properties) were carried out to simulate the actual wearing environment of the sports clothing. This study will create a new scope of research opportunities in the field of bi-layer sports textiles.

This study was conducted to explore the influence of fibre blend and structural tightness factor on the comfort level of sportswear and to find the suitable fibre blend for active sportswear clothing.

The purpose of this paper is to investigate thermal comfort performances of socks produced from cotton and regenerated cellulosic fiber yarns by thermal resistance (by a newly designed foot thermal manikin), moisture management tester (MMT) parameters and permeability (air and water vapor) tests.

Single jersey fabrics and socks were knitted from 30 Ne yarns produced from cotton, different regenerated cellulosic fibers (viscose, modal, bamboo, micromodal, Tencel®, Tencel LF®) and their blends. Thermal resistances of the socks were compared by a newly developed thermal foot manikin in a more realistic way than measurements in fabric form. Besides air and water vapor permeability, moisture management parameters of the fabrics were tested to differentiate performances of cellulosic fibers.

Results show that air permeability, liquid absorption and transfer parameters measured by MMT are generally identical and better for regenerated cellulosic fabrics than cotton. Micromodal and Tencel® have better performances for liquid transfer and overall moisture management capacities are superior for bamboo and Tencel LF®. Thermal resistances of the socks are minimum for Tencel LF® having a cross-linked structure and maximum for viscose socks.

It is thought that thermal resistance measured in socks form is more realistic than fabric measurements and results of this study that can be valid for all knitted garments. Moreover, comprehensive material plan of the study is valuable for getting reliable results for regenerated cellulosic fibers that have small differences in cases of thermal resistance and liquid transfer.

The purpose of this paper is to analyze the performance of a data center and thermal management by using phase change material (PCM). Numerical studies were conducted for two dimensional model of data center and installation of PCM at different locations.

Finite volume method was used for the unsteady problem, while impacts of air velocity and PCM location on the flow field, thermal pattern variations and phase change dynamics were evaluated. Three different locations of the PCM were considered while air velocity was also varied during the simulation. Thermal field variations and cooling performance of the system for different PCM location scenarios were compared.

It was observed that the installation of the PCM has significant impacts on the vortex formation, thermal field variation within the system and its performance. The left, right and top wall installation of the PCM changed the thermal patterns near the heat cell of the data centre. The phase change process is fast for the upper wall installation of the PCM, while the discrepancy of the melt fraction dynamics between different air flow at this position is minimum. The case where PCM placed in the upper wall at the highest air velocity is the best configuration in terms of heat storage. The utilization of PCM and changing its locations provide an excellent tool for thermal management and cooling performance of data centre.

Results of this study can be used for initial design and optimization of cooling systems for thermal management of data centers while the importance of the high-performance computing becomes very crucial for the advanced simulations in different technological applications.

Proper thermal management is a key to improve the efficiency and reliability of light-emitting diodes (LEDs). This paper aims to report the influence of applying thermally conductive materials on thermal performance of indium gallium aluminum phosphide (InGaAlP)-based thin-film surface-mounted device (SMD) LED.

The LED thermal and optical parameters were determined using the combination of thermal transient tester (T3Ster) and thermal and radiometric characterization of power LEDs (TeraLED) instruments. The LED was mounted on FR4, 2W and 5W aluminum (Al) package substrates. Measurements were carried out by setting different boundary conditions: air between LED package and substrate and using thermally conductive epoxy (TIM A) and adhesive (TIM B) of thermal conductivity 1.67 and 1.78 W/mK, respectively.

For LED mounted on FR4 package, the total real thermal resistance is improved because of TIM B by 6 and 9 per cent at 50 and 100 mA, respectively. Likewise, the relative decrease in total thermal resistance of LED on 2W Al package is about 9 and 11 per cent. As well, for LED mounted on 5W Al package, the total real thermal resistance is reduced by 2 and 4 per cent.

No much work can be found in the literature on thermal interface material effects on thermal performance of low-power SMD LED. This work can assist in thermal management of low-power LEDs.

The purpose of this work is to investigate the effect of filament composition with different specifications on the thermal comfort properties of bi-layer knitted fabrics.

In this paper eight bi-layer knitted fabrics with the same knitting structure but different filament compositions were prepared, and the thermal-wet comfort properties of these fabrics were examined. According to experimental data, the effect of filament composition on the thermal comfort properties of fabric was analyzed.

The increasing difference of hydrophilicity between inner and outer layers resulted in the enhancement of moisture management properties. Better thermal-physiology performance was exhibited by fabrics made up of finer and circular section fibers. Excellent thermal transfer, drying performance and one-way water transport capacity benefited the improvement of dynamic cooling effect of fabrics.

This work provides a useful and effective method for the development of bi-layer knitted fabric applied for sports and summer clothing.

The purpose of this paper is to present a novel nanostructured polymer‐metal composite film providing continuous all‐metal thermally conductive pathways, intended to meet future performance requirements on thermal interface materials (TIMs) in microelectronics packaging applications.

Porous polymer structures with a thickness of approximately 100 μm were manufactured using electrospinning technology. Pressure‐assisted infiltration of low‐melting temperature alloy into the porous polymeric carrier resulted in the final composite film. Thermal performance was evaluated using an accurate and improved implementation of the ASTM D5470 standard in combination with an Instron 5548 MicroTester. Finally, a brief comparative study using three current state‐of‐the‐art commercial TIMs were carried out for reference purposes.

Composite films with continuous all‐metal thermally conductive pathways from surface to surface were successfully fabricated. Thermal resistances down to 8.5 K mm² W⁻¹ at 70 μm bond‐line thickness were observed, corresponding to an effective thermal conductivity of 8 W m⁻¹ K⁻¹, at moderate assembly pressures (200‐800 kPa), more than twice the effective thermal conductivity of the commercial reference materials evaluated.

A unique high‐performance nanostructured polymer‐metal composite film for TIM applications with the potential to meet the microelectronics industry's future demands on thermal performance and cost efficiency is presented.