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The purpose of this paper is to solve the problem of weak low-frequency vibration measurement capability of FBG accelerometer, and propose a FBG accelerometer based on cross reed.

This study proposed a new type FBG acceleration sensor based on cross reeds. When the sensor vibrates, the mass block in the new structure rotates around the center of the cross reeds, which could eliminate the impact of friction, reduce the natural frequency of the sensor and improve its sensitivity. This study theoretically analyzed the impact of several structural parameters on the sensitivity and natural frequency of the proposed sensor and used COMSOL to perform static stress analysis and modal simulation; in this study, a test system was built to test the performance of the proposed sensor.

The test results revealed that the proposed sensor had a natural frequency of 94 Hz; within a low-frequency range of 1–65 Hz, its sensitivity response was flat, the dynamic range was 81.89 dB, the sensitivity was 243.59 pm/g and the linearity was 99.97%. The cross reeds effectively strengthened the structural stability, the relative standard deviation of the repeatability of the sensor was 0.89% and the transverse crosstalk in the working frequency band was −26.97 dB.

This study innovatively proposes the structure of the two symmetrical cross reeds, which can improve sensitivity by eliminating the influence of friction, and the structure of cross reeds can effectively suppress the influence of lateral crosstalk. The proposed sensor can realize real-time accurate measurement of low-frequency weak vibration signals.

The purpose of this paper is to develop a high-performance composite emulsion cement waterproof coating. The coating has excellent durability and is effective in protecting cement mortar substrates from harmful ions.

The polymer cement waterproof coatings with different emulsion compounding ratios were tested for mechanical properties and water resistance after alkali immersion, water immersion, thermal aging and UV aging, and the coatings were analyzed by infrared spectroscopy after aging to evaluate its durability. Meanwhile, the coating that presents favorable durability was applied to cement mortar test blocks. The protective effect of the coating on the test blocks was tested by immersion method, and X-ray diffraction analysis was performed on the eroded test blocks.

The coating with neoprene latex/acrylate latex weight ratio of 90/10 presents favorable durability and has superior overall performance. Besides, when it is applied to cement mortar blocks, the coatings effectively reduced the erosive effect of harmful ions on cement mortar blocks, resulting in much lower mass change ratios and less internal structural damage of the blocks significantly.

The obtained coating will be of great application potential for use in building waterproofing construction. Moreover, the coating can practically prevent chloride ions and sulfate ions from penetrating cement-based materials.

This study aims to solve the problem of temperature cross sensitivity of fiber Bragg grating in structural health monitoring, proposing a novel acceleration sensor based on strain chirp effect which is insensitive to temperature.

A kind of M-shaped double cantilever beam structure is developed. The fiber grating is pasted in the gradient strain region of the beam, and the chirp effect is produced under the action of non-uniform stress, and then the change of acceleration is converted into the change of reflection bandwidth to demodulate and eliminate the temperature interference. Through theoretical analysis, simulation and experimental verification with rectangular beam sensor.

The results show that the sinusoidal curvature beam sensor is insensitive to the change of temperature and is more likely to produce chirp effect. The sensitivity is about 317 pm/g, and the natural frequency is 56 Hz.

This paper fulfils an insensitive to temperature changes sensor which has effectively solved the temperature cross-sensitivity problem in building structure health monitoring.

The area of communication with its multistrand, interdisciplinary webbing presents a challenge to the bibliographer seeking to develop a collection. Describes a project at the University of Alabama in which a subject‐special policy was written to address the complex issues involved in collection, the format selected for use and the collegial working relationship between representatives from the College of Communication and the university subject bibliographer. Details the outcome of this investigation along with a description of the policy which outlines parameters for six fields of study — advertising, public relations, telecommunication, film, speech communication, and journalism.

The research intends to investigate the different typological and morphological characteristics of the neighbourhood spaces produced by different urban dynamics since the late nineteenth century in Turkey.

The main problem that drives the research is that a significant increase in the construction of gated communities has started to be seen in the last five years as a solution to safety issues in Turkey. However, these gated communities as safe-spaces have resulted in the danger of destroying neighbourhood life's physical and social dynamics by changing their spatial configuration. The study offers an analytical framework structured from defensible space theory and other safe-space theories in the literature. It has analysed the effect of physical characteristics of urban fabric on the production of safe-space in neighbourhoods through mappings and site observations. The case studies are conducted in three different morphological periods in Turkey, which are the Seyrancik neighbourhood in Bolu (the Ottoman Period), the Subayevleri neighbourhood in Ankara (the Republican Period) and the Karaman neighbourhood in Sakarya (the Liberalisation Period).

The analysis concludes that any type does not come to the fore in the production of defensible space in terms of its spatial features, but each has various strengths and weaknesses. As a result, this study emphasises the role of design in providing defensible neighbourhoods in the case of Turkey's cities and reveals the aspects that will guide the design of an urban and housing form in terms of the safety–environment relationship in Turkey.

The significance of the study is the comparative analytical approach to studying the housing development and demonstrates a method for analysing safety issues in the transformation process of neighbourhood structures in Turkey.

The purpose of this paper is to propose a pressure-, temperature- and acceleration-sensitive structure-integrated inductor-capacitor (LC) resonant ceramic sensor to fulfill the measurement of multi-parameters, such as the measurement of pressure, temperature and acceleration, simultaneously in automotive, aerospace and aeronautics industries.

The ceramic-based multi-parameter sensor was composed of three LC tanks, which have their resonant frequencies sensitive to pressure, temperature and acceleration separately. Two aspects from the specific sensitive structure design to the multiple signals reading technology are considered in designing the multi-parameter ceramic sensor. Theoretical analysis and ANSYS simulation are used in designing the sensitive structure, and MATLAB simulation and experiment are conducted to verify the feasibility of non-coverage of multi-readout signals.

It is found that if the parameters of sensitive structure and layout of the LC tanks integrated into the sensor are proper, the implementation of a multi-parameter sensor could be feasible.

The ceramic sensor proposed in the paper can measure pressure, temperature and acceleration simultaneously in harsh environments.

The paper creatively proposes a pressure-, temperature- and acceleration-sensitive structure-integrated LC resonant ceramic sensor for harsh environments and verifies the feasibility of the sensor from sensitive structure design to multiple-signal reading.

The objective of this paper is to measure the differences in heat transfer properties of refined hydrocarbon distillate fractions that are commonly used as base oils in aluminium sheet cold rolling applications and assess if the heat transfer coefficient (HTC) values for these oils can be predicted from their compositions. The composition and physical properties of these fluids affect their tribological behaviour by influencing hydrodynamic lubrication, wear debris removal and cooling.

A purpose-built test rig was used to measure HTCs for a wide range of hydrocarbon solvents used as aluminium cold rolling oils. The results are expressed in the form of the HTCs relative to those of 14- to 16-carbon-chain-length normal paraffins. Measured HTC values were compared to values calculated from oil compositions and from the thermal conductivities of compounds representing different classes of typical oil components.

There were significant differences between the heat transfer properties of various hydrocarbon solvents, and these differences could be estimated from their content of normal and simple iso-paraffins and heavily branched and cyclic hydrocarbons. The HTC of hydrocarbon mixtures increases with the increasing content of n-paraffinic compounds.

This paper shows how one can estimate the relative HTCs of oils of known compositions, based on the relative thermal conductivities of model compounds. This is relevant to prediction of cooling properties of aluminium cold rolling base oils.

The structure‐borne sound generated by power equipment can be isolated effectively through vibration absorber under hull base structures. The practical vibration isolation performance is limited due to the weight, size and cost. The dramatic attenuating wave propagation characteristic of hull base without adding weight is essential to the vessel acoustic stealth.

The characteristics of vibration wave propagated from typical shape base link structures have been investigated according to impedance mismatch and wave conversion in non‐homogeneous structure. The hull base is simplified to three degrees of freedom damped system through the mechanical impedance method. The influence of blocking mass weight, as well as location properties to the base vibration isolation performance have been discussed. Furthermore, the structure‐borne sound design of a typical hull base is carried out.

The impedance mismatch of the hull base is further increased by the comprehensive use of high transmission loss base link structures, blocking mass as well as damping layer. The effectiveness of structure‐borne sound design is verified through numerical calculation together with underwater model test. The test data show that the noise has been reduced larger than 3 dB.

The paper describes what is believed to be the first application of the high transmission loss base in hull structures based on the literature survey. The method of structure‐borne sound design of a typical hull base can be applied in different types of vessels.

When dwellings fail to respond to residents’ needs, housing will suffer from segregation and buildings will possibly be demolished ahead of their time. This paper focuses on the lack of variation in the sizes of dwellings as a factor in residential segregation. It examines this issue in the context of Finnish mass housing built in the 1960s and 1970s. The purpose of the paper is to review how mass housing layouts can be adapted to produce the currently absent flat sizes.

The paper operates at the intersection of human geography, building stock research and adaptability research. First, statistical data are utilized to investigate how dwellings and households of different sizes are distributed over the Finnish housing stock. Second, the building layouts of mass housing are examined in detail. Third, the potential that flats in mass housing have for size modification is reviewed.

There is a disparity of available dwelling sizes between different housing types, and statistics show that the proportion of large households has decreased significantly in blocks of flats over the last decades. The lack of large dwellings in mass housing may contribute as one factor to the segregation of the neighborhoods built in the 1960s and 1970s. The findings show how the variation of apartment sizes can be increased in mass housing.

The housing stock is rarely examined in detail in segregation research, even though it is a major determinant for a city’s social structure. This paper argues that to address segregation sustainably, it is necessary to understand the housing stock better and to view it as an adaptable asset.

A domain‐adaptive technique which maps the unknown, time‐dependent, curvilinear geometry of annular liquid jets into a unit square is used to determine the steady state mass absorption rate and the collapse of annular liquid jets as functions of the Froude, Peclet and Weber numbers, nozzle exit angle, initial pressure and temperature of the gas enclosed by the liquid, gas concentration at the nozzle exit, ratio of solubilities at the inner and outer interfaces of the annular jet, pressure of the gas surrounding the liquid, and annular jet's thickness‐to‐radius ratio at the nozzle exit. The domain‐adaptive technique yields a system of non‐linearly coupled integrodifferential equations for the fluid dynamics of and the gas concentration in the annular jet, and an ordinary differential equation for the time‐dependent convergence length. An iterative, block‐bidiagonal technique is used to solve the fluid dynamics equations, while the gas concentration equation is solved by means of a line Gauss‐Seidel method. It is shown that the jet's collapse rate increases as the Weber number, nozzle exit angle, temperature of the gas enclosed by the annular jet, and pressure of the gas surrounding the jet are increased, but decreases as the Froude and Peclet numbers and annular jet's thickness‐to‐radius ratio at the nozzle exit are increased. It is also shown that, if the product of the inner‐to‐outer surface solubility ratio and the initial pressure ratio is smaller than one, mass is absorbed at the outer surface of the annular jet, and the mass and volume of the gas enclosed by the jet increase with time.