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The effects of oxygen on solder surface tension, wetting time and surface damping are presented. Oxygen levels greater than 10 ppm lower surface tension, increase wetting time and increase surface damping. Decreased surface tension leads to higher misalignment defects in reflow soldering, but can lower the incidence of dewetting. Increased wetting times can increase non‐wetting defects in both wave and reflow soldering, especially when using no‐clean fluxes. Increased surface damping can lead to lower bridging rates in wave soldering, provided that the oxygen level and flux levels are properly balanced. Choosing the optimum oxygen level for production soldering is trade ‐ off between the stability and the versatility of the process. The most stable soldering processes will be those performed in an inert atmosphere with less than 10 ppm oxygen .These processes are insensitive to variations in soldering machine operating parameters (i,e. a larger process window).This is most desirable for manufacturers soldering large volumes of a given circuit board. The soldering process can be optimised by optimising the circuit board design. The most versatile soldering processes will be those performed in an inert atmosphere with controlled addition of oxygen in the range of 100 ppm to 10,000 ppm (1%). This will be most desirable to manufacturers soldering short runs of a large variety of circuit boards. The soldering process is best optimised by controlling the soldering machine operating parameters (oxygen, flux, preheat, conveyor speed, etc.).

Nowadays, textiles play a striking role in various medical applications. Compression bandages are the most essential medical fabrics that help treat venous flow and edema. This study aims to investigate the characteristics of different woven compressive bandage structures produced using compact cotton and cotton/lycra.

Four samples were weaved by matt-plain2/2, twill2/2, stripe-stain4 and mock-leno structures. Several properties were tested that related to structural performance. Tensile strength, elastic and sub-bandage pressure are considered the main functional properties. Three different analysis tools were performed: chart-diagram, one-factor ANOVA and radar chart area.

The woven structures critically affected the performance of woven compression bandage samples as well as their classifications.

The woven structures critically affected the performance of woven compression bandage samples as well as their classifications.

Drawing on theories of development economics and sustainable tourism, this research explores the differences between sovereign and nonsovereign small island tourism economies (SITEs) and identifies the antecedents and effects of overtourism in the Caribbean.

The research design is based on a comparative case study of selected Caribbean SITEs. Case study research involves a detailed empirical inquiry that investigates a contemporary phenomenon within its real-life context. The main purpose of a case study is to provide a contextual analysis of the conditions and processes involved in the phenomenon under study. A comparative case study is an appropriate research methodology to explore new multi-faceted concepts with limited empirical evidence.

The results confirm previous studies that nonsovereign SITEs have a distinctive overdrive toward tourism specialization. Moreover, the findings indicate that overtourism is driven by both global and domestic policy factors and generates significant economic volatility, social inequality and ecological stress. The paper discusses the tourism policy implications of the evolving economic disconnectedness, environmental decay and social tensions in SITEs in the Caribbean.

Policy recommendations are presented for transitioning toward a more inclusive development and strengthening the resilience of small island tourism development in the Caribbean.

FLIGHT experience during recent years with roller strip maps driven from Doppler groundspeed data in an ‘along’ and ‘across’ track mode has demonstrated many of the undoubted advantages of a pictorial display of ground position.

‘The enlarged Community cannot afford a gentle period of gradually growing together.’

This study aims to clarify the key factors among physical‐mechanical properties of fabrics in relation to the dynamic pressure performance of compression garment.

The physical‐mechanical properties of 16 different fabrics were measured using a KESF standard evaluation system and INSTRON tensile tester, and the garment pressure was measured by dynamic pressure measuring system. Grey correlation analysis is used to determine the correlation degree of fabric physical‐mechanical properties and dynamic pressure magnitude.

The mechanical behaviors (e.g. tensile, shearing, and bending) and physical characteristics are different in elastic fabrics with varied content of elastic fiber, kinds of yarn, et al. Grey correlation analysis is a valid method to analyze the indices of a system, quantize them and put them in order. All the degrees of Grey correlation are more than 0.6. The degree of grey correlation between tensile force (F), shearing rigidity (G) and bending rigidity (B) are higher than others, hence it is conducted that these would significantly effect on garment pressure. The quantitative regression equations between pressure magnitude at extension of 50 percent and the individual key parameters (mean values in wale and course directions) of tested samples are illustrated.

The other parameters (e.g. fabric structure, yarn fineness, and pre‐tension, et al.) should be taken into account. Further, an integrative mathematic model would be established, which could predict the garment pressure directly from the physical‐mechanical properties of fabric.

The present study indicates that pressure magnitude of elastic fabric is an integrative action performed by physical‐mechanical properties. The developed illustrative equations and method offer a rational and practical tool for assessing pressure functional performance of elastic fabric in the stages of design and product development.

The conception of a compression garment that applies a desired interface pressure level has been a great challenge for therapists and compression garment manufacturers even today. The purpose of this study is to develop a new method for designing a compression legging that exerts Class I interface pressure to the lower limb.

This research presents a new method for the design of Class I compression garment. It consists of theoretically calculating the circumferences of the Class I compression legging based on the reduction factors. To assess the effectiveness of the method, we used both objective and subjective evaluations. For the objective evaluation, we have developed a measuring device to measure Class I legging interface pressure in different measuring points using a force pressure sensor. Concerning the subjective evaluation, 10 healthy female subjects agreed to take part in this study in order to evaluate the ergonomic comfort when wearing the designed compression legging.

Participating subjects delivered their feeling about comfort and motion restriction during the use of the legging. Referring to the volunteers’ answers, the Class I compression legging can be described as comfortable and has a satisfactory fit during wear.

The important feature of this study was the effectiveness of the new designing method in producing a compression legging that delivers the desired amount of pressure and offers a comfort sensation during wear. The outcome of this research is a new method that could be used to create a variety of compression garments that can apply different pressure levels.

DESPITE the quite extensive literature on foam, the mechanism of its formation and decay does not appear to be widely appreciated. Most fundamental research has been orientated towards maximum foam in aqueous solutions, whereas the desire in aircraft engines is for minimum foam in oil ‘solutions’. Further, the numerical results obtained experimentally depend on the details of experimental procedure, which makes correlation of existing data very uncertain.

It was typical in nineteenth century economic thought to view the tensions between the interests of capital and labour as critical to industrial society. Yet later economic thought has generally reduced these tensions to those captured in contract theory. Explores how this narrowing of focus has cast an important source of contemporary social dynamics into the shadows. A broad survey is made of the various ways in which capital‐labour tensions are manifested in today′s advanced industrial economies, with special attention given to the case of the USA. Concludes with a discussion of how intensified international competitiveness, combined with our increasing distance from the threat of material privation, may force societies to restructure their economies so as to eliminate the source of capital‐labour tensions. The task facing liberal economic thought is to expand its scope to better provide guidance for meeting this challenge.