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The purpose of this study is to measure the mass diffusion coefficient of nitrogen in jet fuel using digital holography interferometry for cost-effective designing and modeling of the aircraft tank inerting system.

The mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels were measured by digital holography interferometry at temperatures ranging from 278.15 to 343.15 K. The Arrhenius equation is used to adequately describe the relationship between mass diffusion coefficients and temperature. The viscosities of RP-3 and RP-5 jet fuels were also measured to examine the accuracy of the Stokes–Einstein model in calculating mass diffusion coefficients.

As temperature increases from 278.15 to 343.15 K, the mass diffusion coefficients increase 4.23-fold for N₂ in RP-3 jet fuel and 5.13-fold for N₂ in RP-5 jet fuel. The value of Dµ/T is not constant as the Stokes–Einstein equation expressed, but is a weak linear function of temperature.

A more accurate diffusion model is proposed by fitting the measured Dµ/T with the temperature and calculating the mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels within 10 per cent relative deviation.

A measurement system for mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels was constructed based on the digital holography interferometry. The mass diffusion coefficient can be expressed by a uniform polynomial function of temperature and viscosity.

The purpose of this paper is to review the application of digital holography in studies of the corrosion of metallic materials.

Digital holography is used for in situ observation of the dynamic processes at the electrode | electrolyte interface and on the electrode surface during the corrosion dissolution of metallic materials.

Digital holography is an effect method to in situ observe the corrosion processes, and it can provide a direct experimental foundation for studying the corrosion mechanism.

Even though there are several challenges, digital holography will play a significant role in studying corrosion processes.

The purpose of this paper is to provide a comprehensive review of a non-contact full-field optical measurement technique known as digital image correlation (DIC).

The approach of this review paper is to introduce the research pertaining to DIC. It comprehensively covers crucial facets including its principles, historical development, core challenges, current research status and practical applications. Additionally, it delves into unresolved issues and outlines future research objectives.

The findings of this review encompass essential aspects of DIC, including core issues like the subpixel registration algorithm, camera calibration, measurement of surface deformation in 3D complex structures and applications in ultra-high-temperature settings. Additionally, the review presents the prevailing strategies for addressing these challenges, the most recent advancements in DIC applications across quasi-static, dynamic, ultra-high-temperature, large-scale and micro-scale engineering domains, along with key directions for future research endeavors.

This review holds a substantial value as it furnishes a comprehensive and in-depth introduction to DIC, while also spotlighting its prospective applications.

The failure of copper‐plated holes in dielectric laminates during thermal cycling is a serious problem for the electronics industry. The large difference in out‐of‐plane thermal expansion between the dielectric laminate and the copper plating can cause the copper plating to deform and fail as the board is thermally cycled. The purpose of this study was to demonstrate the feasibility of using electro‐optic holographic interferometry (EOHI) to measure deformation around plated holes and to evaluate methods for estimating the stress in the barrel plating. It was demonstrated that EOHI was more than adequate to resolve the out‐of‐plane thermally induced displacement field around an array of plated‐through holes. The displacement sensitivity was better than ±10 nm with high spatial resolution (92 ?m horizontally and 75 ?m vertically).The expansion was reasonably linear from 30°C to 120°C. The deformation around the individual holes was not axisymmetric. It is suggested that the method for estimating barrel stresses may be too sensitive to thickness and architecture variations in the pad for reliable stress estimates. An alternative scheme for estimation of barrel stresses based on thermal strain energy evaluation is described.

The purpose of this paper is to provide a review of three‐dimensional (3D) measurement technologies and their applications.

This paper first describes 3D measuring techniques and then considers a selection of key applications, citing a number of specific examples. Reference is also made to certain new developments and research activities.

It is shown that both active and passive techniques are used to conduct 3D measurements. The former includes various forms of laser scanning such as time of flight, triangulation and phase measurements and photogrammetry is the main passive method. Laser‐based Doppler shift techniques are used to monitor dynamic phenomena, notably vibration, in three dimensions. These methods are used across a diversity of industries and disciplines in a wide and varied range of applications.

The paper provides a technical review of the leading 3D measurement technologies and their uses.

Looks at complex applications for lasers, optics and electro‐optics, including use in areas such as inspection and measurement. Features ESPI (electronic speckle pattern interferometry) systems and their use in the automotive industry and presents a case study involving specialist systems used in areas such as measuring print rollers and inspecting engine cylinder walls. Touches on other new techniques in the field such as chemical imaging and the recent use of Doppler vibrometry to quantify pure bending vibrations in rotating components.

A major demonstration of industrial research and development capability was mounted at the Hanover Fair this year by the Measurement Technology section of Volkswagen Research. It included a variety of laser interferometry applications, acoustic mapping with the help of an industrial robot, and a new high‐speed camera.

The subject of this paper is the application of holograms in cultural institutions. The purpose of this paper is to define the potential areas of hologram use in libraries, particularly in education and promotion, and also in services.

The method of analysis and criticism of literature was used. Based on a search conducted through Google Scholar for the 2006-2016 period, the current state of research on the use of holograms in cultural institutions was established. Subsequently, in order to find examples of hologram use in libraries, museums, galleries, and social organizations, an established set of queries was used to systematically search network resources using global search engines and metasearch engines. The initial list of results was narrowed down to the most relevant. On the basis of the above fact, the main areas of hologram use in cultural institutions were defined and examples of best practices were selected according to chosen criteria. The comparative method then was used to determine potential areas of application of holographic techniques in libraries. Finally, SWOT analysis – the situational analysis method known to management sciences – was used to determine opportunities and threats related to the use of holograms in cultural institutions.

Holograms have broad potential use in libraries that is even broader than initially assumed because they are not limited to education, promotion and services, and can also be used in documentation, research and exhibitions. The use of holograms can bring many benefits, but it is also associated with certain risks that need to be considered.

The results can be widely used in practice as a framework for the implementation of holographic techniques in libraries.

The paper can help initiate debate on the opportunities and risks of using holograms in cultural institutions.

The issue of the use of holograms has not yet been widely discussed in library and information science scientific journals.

Determining the variation law of the oxygen concentration in the ullage space of the fuel tank is the key to the design of the inert system. Among various factors affecting the oxygen concentration in the ullage space of the fuel tank, the temperature difference between day and night shows particular importance while relevant analysis and calculation are scarce.

This study establishes a theoretical simulation model of the central wing fuel tank of an aircraft according to the relevant provisions of day-night temperature variation in FAR25 airworthiness regulations, verifies the model with the existing experimental data and discusses the corresponding relationship between the oxygen concentration in the ullage space of the fuel tank and the day-night temperature difference. The influence of day and night temperature difference, fuel type, fuel load rate, initial oxygen concentration, dissolved oxygen evolution and other factors on the oxygen concentration in the ullage space of the fuel tank were analyzed, and the limit of initial oxygen concentration of the fuel tank before the shutdown at night meeting the requirements of the airworthiness provisions was proposed.

The results show that the temperature difference between day and night, fuel load rate, initial oxygen concentration and other factors have different effects on the oxygen concentration in the ullage space of fuel tank. The initial oxygen concentration limit before shutdown shall be 2% below the 12% oxygen concentration stipulated by FAA.

The research results in this paper will be of good reference value to the design of the inert system and the calculation of the flammability exposure evaluation time. This paper aims to be good reference of the design of the inert system and the calculation of the flammability exposure evaluation time.

The research results of this paper can provide practical guidance for the current civil airworthiness certification work.