Do Blue Flag promotions influence tourists’ willingness to pay a price premium for coastal destinations?

The Blue Flag is a popular eco-label in tourism. This study aims at examining the effectiveness of Blue Flag promotion on tourists' willingness to pay a price premium to coastal destinations via two online experiments. Study 1 shows (n = 152) that the Blue Flag stimulates higher willingness to pay a price premium for coastal destinations directly as well as indirectly through self-congruity and destination brand identification. Study 2 (n = 160) used a new sample to enhance external validity and generalizability of the Study 1 findings. Study 2 shows that destination brand quality and destination brand identification serially mediate the effect of Blue Flag promotions on the tourist's willingness to pay a price premium. The findings suggest that destination managers should deploy the Blue Flag Logo in destination promotions to enhance self-congruence, destination brand identification, perceived destination quality, and the tourist's willingness to pay a price premium

Comment on "Evidence for Quantized Displacement in Macroscopic Nanomechanical Oscillators"

In a recent Letter, Gaidarzhy et al. [1] claim to have observed evidence for "quantized displacements" of a high-order mode of a nanomechanical oscillator. We contend that the methods employed by the authors are unsuitable in principle to observe such states for any harmonic mode

Aerial Close-Range Photogrammetry to Quantify Deformations of the Pile Retaining Walls

Today, as structures with life expectancy of more than 100 years are being constructed, it is vital to gain knowledge about the gradual decline in material properties. Accordingly, to ensure the longevity and safety of these structures, monitoring has been incorporated as a fundamental part of their service life. To monitor structural deformation, various methods have been developed, with the most common being the survey of certain points of a structure during and after construction using a total station. New techniques are now being developed, and one of the most promising ones is photogrammetry because it provides a simple method to monitor a structure using unmanned air vehicles (UAVs). This paper is aimed at sharing the strategic steps followed in monitoring the deflection of a simple secant pile retaining wall during excavation and construction of a basement. The monitoring is performed using a commercial UAV in combination with point cloud formation, georeferencing, and comparison software (cloud compare, I-Site Studio, 3D Reshaper, etc.). The monitoring results show very good agreement with the traditional inclinometer deflection measurements and numerical analysis, thereby demonstrating the feasibility of the proposed method. The authors believe that in the future, photogrammetry using UAVs can become the standard method for geotechnical monitoring because of its speed, lower cost and ease of use, when compared to conventional methods, a non-destructive method, and is easy to learn and use

Effect of cyclic shearing on contact surfaces of geo-materials under constant normal force

A large amount of research has been done on conforming surfaces in rock joints as well as on the contact between individual grains; however, not much exist in nonconforming contact surfaces subjected to friction, such as flat contacts between ballast particles, stone columns, or riprap; applications that involve the use of coarse gravel subjected to low vertical stresses. Therefore, this article aims to study changes in contact properties between nonconforming flat contacts between large geo-material particles that have been subjected to cyclic shearing under a constant low vertical force, using a direct shear apparatus. Two different silica carbide sandpapers that do not loose particles were used, to simulate different morphologies, a nominally fine and a coarse surface texture. The results show a passivation of the shear strength where a constant value of friction coefficient is reached after around 15 to 17 cycles for all tests, except the tests at the lowest vertical force. For the tests at the highest vertical force, similar friction coefficients were determined for the coarse and fine surfaces. The mass broken during the 10th and 20th cycles was collected at the end of the tests and seemed to show a linear relationship with the vertical force used in the test. Particle analysis, determined via microscopy, shows that the grading is dependent on the initial topography of the surfaces. Despite being subjected to 10 and 20 cycles of shearing, the broken particles look similar in shape with sharp, jagged edges and having different shapes and roundness values with a large variation, indicating that the breakage was not enough to fill in the space between the particles

Effect of sand paper grading on the shear behaviour of fine-grained sand

This paper presents the results of direct shear test on sand paper reinforced and un-reinforced poorly graded fine-grained sand obtained from natural costal sand deposits of western shore of Cyprus Island. Mining of sand from natural deposits, including beaches, yields an inexpensive source of sand for construction or industrial uses. Samples prepared in identical densities with and without addition of different grading of discrete sand papers have been tested in order to assess the effect of sand paper grading on the shear strength parameters of soil. Laboratory testing program consisting 41 specimens were performed in circular shear box with 63 mm in diameter which were prepared regarding BS 1377-7. Tests are conducted with four vertical confining pressures: 100, 200, 300 and 400 kPa. The test results reveal that the sand paper grading play important role in the shear strength parameters of the soil. It was observed that the choose of grading close to the major percentage of sand particle size results to achieve increase in shear strength at all confining pressures which also results in increase of cohesion and friction angle

Intrinsic dissipation in high-frequency micromechanical resonators

We report measurements of intrinsic dissipation in micron-sized suspended resonators machined from single crystals of galium arsenide and silicon. In these experiments on high-frequency micromechanical resonators, designed to understand intrinsic mechanisms of dissipation, we explore dependence of dissipation on temperature, magnetic field, frequency, and size. In contrast to most of the previous measurements of acoustic attenuation in crystalline and amorphous structures in this frequency range, ours is a resonant measurement; dissipation is measured at the natural frequencies of structural resonance, or modes of the structure associated with flexural and torsional motion. In all our samples we find a weakly temperature dependent dissipation at low temperatures. We compare and contrast our data to various probable mechanisms, including thermoelasticity, clamping, anharmonic mode-coupling, surface anisotropy and defect motion, both in bulk and on surface. The observed parametric dependencies indicate that the internal defect motion is the dominant mechanism of intrinsic dissipation in our samples

The mechanical behaviour of compacted Lambeth-group clays with and without fibre reinforcement

This study investigated the effect of fibre reinforcement on the large strain behaviour of compacted clay samples tested using large triaxial test equipment. A novel specimen preparation method was proposed where peds of clay are compacted to closely simulate the in-situ compaction. A large number of 100 × 200 mm triaxial tests and one-dimensional compression tests were performed using reinforced and unreinforced samples. The behaviour of unreinforced samples was observed to be similar to highly fissured clays; ped compaction generated a random fissure pattern due to the contact between peds. The addition of fibres to the compacted samples created fissures with higher mobility at lower friction than those in the unreinforced samples; hence, the state boundary surface of reinforced clay was below that of the unreinforced clay. With the addition of fibres, the failure mechanism changed from the formation of a shear plane to barrelling, demonstrating that the fibres transferred stresses further away from the shear plane, producing a more homogeneous stress distribution. The preparation method proposed here produced a fissure pattern in the clay that introduced transitional behaviour, which was drastically reduced with addition of the fibres, allowing better normalisation and the definition of a unique boundary surface

The mechanical properties of compacted clay from the Lambeth Group using fibre reinforcement

Slope failures related to pore-water dissipation, stress relaxation and desiccation cracks are major problems occurring in the UK ageing road network. The remediation works are known to cause congestion and delays that, in turn, cause financial loss and discomfort to users. Our industry partner, Mouchel, believe that it is possible to reduce the number of slope failures, maintenance costs and bring large social benefits by using soil reinforcement to reinstate failed slopes. The use of fibre reinforced soils has been a topic of research for many years, however not many applications have been seen so far. Fibres have the potential to reduce environmental impact by improving soil properties and allowing the use of local available soils. In order to increase its use, it is important to understand how the inclusion of fibres can improve soil properties, particularly in heavily overconsolidated soils, where the compacted composite has “peds” carrying properties of the intact soil. To study the soil improvement, a new compaction methodology was developed, mimicking the behaviour of the site compacted composite. Series of drained and undrained triaxial tests were performed in reinforced and unreinforced laboratory compacted samples, as well site compacted samples. In order to better understand the effect of structure, reconstituted samples were also tested. The results show that the reinforced samples, tested below a critical confining pressure, have higher strength than the unreinforced samples, whilst above this pressure the strength reduces. The data revealed that the reinforced samples appear to have a unique critical state line, whilst the unreinforced soil seems to have a transitional behaviour with a set of parallel critical state lines. The normalisation, by the intrinsic normal compression line, shows that it is possible to identify part of the state boundary surface of the compacted samples and these plot above the intrinsic state boundary surface

Monocrystalline silicon carbide nanoelectromechanical systems

SiC is an extremely promising material for nanoelectromechanical systems given its large Young's modulus and robust surface properties. We have patterned nanometer scale electromechanical resonators from single-crystal 3C-SiC layers grown epitaxially upon Si substrates. A surface nanomachining process is described that involves electron beam lithography followed by dry anisotropic and selective electron cyclotron resonance plasma etching steps. Measurements on a representative family of the resulting devices demonstrate that, for a given geometry, nanometer-scale SiC resonators are capable of yielding substantially higher frequencies than GaAs and Si resonators