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To fabricate submicrometer thin membrane of silicon nitride and silicon dioxide over an anisotropically etched cavity in (100) silicon.

PECVD of silicon dioxide and Silcion nitride layers of compatible thicknesses followed by thermal annealing in nitrogen ambients at 1,000°C for 30 min, leads to stable membrane formation. Anisotropic etching of (100) silicon below the membrane through channels on the sides has been used with controlled cavity dimensions.

Lateral front side etching through channels slows down etching rate drastically. The etching mechanism has been discussed with experimental details.

Vacuum sealed cavity membranes can be realised for micro sensor applications.

The process is new and feasible for micro sensor technologies.

The purpose of this paper is to describe the fabrication of a miniaturized membrane type double cavity vacuum‐sealed micro sensor for absolute pressure using front‐side lateral etching technology.

Potassium hydroxide‐based anisotropic etching of single crystal silicon is used to realize the cavities under the membrane type diaphragms through channels on the sides. The diaphragms consist of composite layers of plasma‐enhanced chemical vapour deposition (PECVD) of silicon nitride and silicon dioxide. PECVD of silicon dioxide is done for sealing the channels and the cavity in vacuum. Boron thermal diffusion in low‐pressure chemical vapour deposition of polysilicon layer over the membrane is done for realizing resistors. The fabricated device uses Wheatstone half bridge circuit to read the variation of resistance with respect to an applied pressure.

A double cavity vacuum‐sealed absolute pressure micro sensor has been fabricated successfully using front‐side lateral etching technology and has been measured for pressure range of 0‐0.45 MPa. The measured pressure sensitivity of two pressure sensors is 9.28 and 10.44 mV/MPa.

The paper shows that front‐side lateral etching technology is feasible in the fabrication of small vacuum‐sealed cavities and absolute pressure sensors.

The purpose of this paper is to use finite element method for optimizing the membrane type double cavity vacuum sealed structure for the best achievable sensitivity in a piezoresistive absolute pressure sensor and its validation using a standard complementary metal oxide semiconductor (CMOS) process.

A double cavity vacuum sealed piezoresistive absolute pressure sensor has been simulated and optimized for its performance and an analytical model describing the behaviour of the sensor has been described. The 1×1 mm sensor chip has two membrane type 100×30×1.7 μm diaphragms consisting of composite layers of plasma enhanced chemical vapour deposition (PECVD) of silicon nitride (Si₃N₄) and silicon dioxide (SiO₂) each hanging over 21 μm deep rectangular cavity. Potassium hydroxide (KOH) based anisotropic etching of single crystal silicon using front side lateral etching technology is used for the fabrication of the sensor. The electrical readout circuitry uses 318 Ω boron diffused low pressure vapour chemical vapour deposition (LPCVD) of polysilicon resistors arranged in the Wheatstone half bridge configuration. The sensing structure is simulated and optimized using COMSOL Multiphysics.

Front-side lateral etching technology has been successfully used for the fabrication of double cavity absolute pressure sensor. A good agreement with the fabricated device for the chosen location of the piezoresistors through simulation has been predicted. The measured pressure sensitivity of two tested pressure sensors is 12.63 and 12.46 mV/MPa, and simulated pressure sensitivity is found to be 12.9 mV/MPa for pressure range of 0 to 0.5 MPa. The location of the piezoresistor has also been optimized using the simulation tools for enhancing the sensor sensitivity to 62.14 mV/MPa. The pressure sensitivity is further enhanced to 92 mV/MPa by increasing the width of the diaphragm to 35 μm.

The simulated and measured pressure sensitivities of the double cavity pressure sensor are in close agreement. Sevenfold enhancement in the pressure sensitivity of the optimized sensing structure has been observed. The proposed front-side lateral etching technology can be adopted for making membrane type diaphragms hanging over vacuum sealed micro-cavities for high sensitivity pressure sensing applications.

Food choices profoundly affect one's dietary, nutritional and health outcomes. Using alcoholic beverages as a case study, the authors assess the potential of genetic data in predicting consumers' food choices combined with conventional socio-demographic data.

A discrete choice experiment was conducted to elicit the underlying preferences of 484 participants from seven provinces in China. By linking three types of data (—data from the choice experiment, socio-demographic information and individual genotyping data) of the participants, the authors employed four machine learning-based classification (MLC) models to assess the performance of genetic information in predicting individuals' food choices.

The authors found that the XGBoost algorithm incorporating both genetic and socio-demographic data achieves the highest prediction accuracy (77.36%), significantly outperforming those using only socio-demographic data (permutation test p-value = 0.033). Polygenic scores of several behavioral traits (e.g. depression and height) and genetic variants associated with bitter taste perceptions (e.g. TAS2R5 rs2227264 and TAS2R38 rs713598) offer contributions comparable to that of standard socio-demographic factors (e.g. gender, age and income).

This study is among the first in the economic literature to empirically demonstrate genetic factors' important role in predicting consumer behavior. The findings contribute fresh insights to the realm of random utility theory and warrant further consumer behavior studies integrating genetic data to facilitate developments in precision nutrition and precision marketing.

The purpose of this study is to find a new design that can increase the sensitivity of the sensor without sacrificing the linearity. A novel and very efficient method for increasing the sensitivity of MEMS pressure sensor has been proposed for the first time. Rather than perforation, we propose patterned thinning of the diaphragm so that specific regions on it are thinner. This method allows the diaphragm to deflect more in response with regard to the pressure. The best excavation depth has been calculated and a pressure sensor with an optimal pattern for thinned regions has been designed. Compared to the perforated diaphragm with the same pattern, larger output voltage is achieved for the proposed sensor. Unlike the perforations that have to be near the edges of the diaphragm, it is possible for the thin regions to be placed around the center of the diaphragm. This significantly increases the sensitivity of the sensor. In our designation, we have reached a 60 per cent thinning (of the diaphragm area) while perforations larger than 40 per cent degrade the operation of the sensor. The proposed method is applicable to other MEMS sensors and actuators and improves their ultimate performance.

Instead of perforating the diaphragm, we propose a patterned thinning scheme which improves the sensor performance.

By using thinned regions on the diaphragm rather than perforations, the sensitivity of the sensor was improved. The simulation results show that the proposed design provides larger membrane deflections and higher output voltages compared to the pressure sensors with a normal or perforated diaphragm.

The proposed MEMS piezoelectric pressure sensor for the first time takes advantage of thinned diaphragm with optimum pattern of thinned regions, larger outputs and larger sensitivity compared with the simple or perforated diaphragm pressure sensors.

AN article on the production of an acro‐engine is far more difficult to write than one about an airframe, for the majority of the operations take place in the machine shop, leaving one with two alternatives—a brief, uninformative outline, or a laboriously detailed, dull account. The form of the present article is an attempt to give both an interesting and informative, although of necessity incomplete, account of the production of the Alvis Leonides. Since Alvis Ltd. are, comparatively speaking, newcomers to the aircraft industry, the extent and facilities of their works are not generally known, so these are dealt with at some length, while the actual machining operations are covered by a selection of photographs, accompanied by explanatory captions, of some of the most interesting parts and operations.

This study aims to investigate the impact of varying solid ratios in epoxy-based formulations on their corrosion resistance. The amounts of epoxy resin in the formulations were kept constant, and the behavior of paints with varying filler ratios was compared. It also examines the tensiometric and rheological properties of these formulations.

Three distinct epoxy-based formulations cured with amine compounds were prepared. The formulations underwent various testing protocols to evaluate their performance: coating tests: coated panels with cross lines were exposed to humidity and corrosive atmospheres. Tensiometric Measurements: Conducted using pendant and sessile drop methods. Rheological characterizations: ıncluded flow tests, oscillatory amplitude sweeps and three-interval thixotropy tests. Corrosion resistance assessment: after the panels were immersed in methanol for one week, measurements were taken using electrochemical impedance spectroscopy. Additional tests: neutral salt spray (NSS) and humidity testing.

The study observed that the coated panels, after exposure to NSS and humidity testing, demonstrated corrosion resistance within acceptable limits as defined by the ISO 12944-6 standard. Results indicate that the epoxy-based formulations show potential for improvements in paints and coatings, suggesting promising advancements in their anticorrosion performance.

This research provides insights into how the solid ratios in epoxy-based formulations influence their performance, particularly in terms of corrosion resistance, tensiometric and rheological properties. The findings contribute to the development of more effective epoxy resin-based coatings for industrial applications.

EACH September the eyes of the aeronautical World turn towards the S.B.A.C. Air Display and Exhibition with interest unequalled by any other event. It is fitting that the Display is now held each year at the airfield of the Royal Aircraft Establishment, one of the world's most prominent aeronautical research centres. This interest becomes increasingly keen too, as the preview day comes closer, because new prototypes of unorthodox designs often appear a short time before the Show to illustrate the results of years of careful planning, development and research of the particular company. These designs often mould the path of progress for smaller countries without the economic resources to forge the way ahead alone. Most British citizens are very proud of their country's place in aviation today, both in the military and civil fields. This is understood by most foreigners because it is clear that Britain has won a place in aeronautical development second to none.

This paper examines social impact investing (SII), a growing source of investment from the Global North to the Global South celebrated as a new way of doing good in low-income countries, but bearing elements of neoliberalism that can reify post-colonial contexts.

A microfoundational, autoethnographic approach is used based on the author’s experiences and emotional epiphanies while engaged in an activist entrepreneurial enterprise. The author’s goal was to effect positive social change with Indigenous Mexican producers of mezcal liquor.

Despite the best of intentions and following best practices for SII, the expected altruistic outcomes were eclipsed by inadvertent post-colonial behaviours. Neoliberal foundations of financialization gave primacy to the perspectives and egos of the investors rather than meaningful impact for the Indigenous beneficiaries.

Based on the findings, three areas are presented for further research. First, how Global North social impact investors balance the ego of their motivations with the altruism of intended outcomes for beneficiaries. Second, what ownership structures of Global North investments allow for social benefits to flow through to intended beneficiaries. Third, how post-colonial power imbalances can be redressed to give an equal position to Global South beneficiaries as people, rather than financial metrics indicating only that they have become less poor.

By using autoethnographic methods that expose the vulnerability of the researcher, unique insights are generated on what happens when good intentions meet with a post-colonial context. The neoliberal underbelly of SII is revealed, and ways to make improvements are considered.

This paper examines the internationalization response of entrepreneurs in Hong Kong to the institutional upheaval of the Umbrella Revolution (UR), analyzed through the lens of post-colonial theory.

Inductive methods are applied to interview data on dimensions of ethnic background (local Chinese, regional Chinese and British expatriates) and geographical scope of business (Hong Kong only or global). The analysis consists of first-order concepts, second-order themes and aggregate dimensions which link the results to post-colonial theory and international entrepreneurial orientation (IEO).

Amongst informants with a high international entrepreneurial orientation (IEO), strategy response to upheaval is highly influenced by ethnic background and geographical flexibility in a post-colonial context. Applying Bhabhaian post-colonial theory, the Hong Kong UR is found to be a liminal space, where internationalization strategy in response to upheaval belies subconscious, ethics-laden constructions of post-colonial identity, manifesting in counterintuitive ways.

This paper addresses the paucity of studies on liminality and entrepreneurship and on how IEO responds to acute uncertainty in the business environment. Further, IEO is found to be an individual rather than a firm-level construct. Finally, a post-colonial theory is considered in a larger context of liminality and how the transitional self of entrepreneurs comes to terms with institutional upheaval.