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In this paper the use of classical strain measures in analysis of trusses at finite deformations will be discussed. The results will be compared to the ones acquired using a novel strain measure based on the Hyperbolic Sine function. Through the evaluation of results, algebraic development and graph analysis, the properties of the Hyperbolic Sine strain measure will be examined.

Through graph plotting, comparisons between the novel strain measure and the classic ones will be made. The formulae for the implementation of the Hyperbolic Sine strain measure into a positional finite element method are developed. Four engineering applications are presented and comparisons between results obtained using all strain measures studied are made.

The proposed strain measure, Hyperbolic Sine, has objectivity and symmetry. The linear constitutive model formed by the Hyperbolic Sine strain and its conjugated stress presents an increasing stiffness, both in compression and tension, a behavior that can be useful in the modeling of several materials.

The structural analysis performed on the four examples of trusses in this article did not consider the variation of the cross-sectional area of the elements or the buckling phenomenon, moreover, only elastic behavior is considered.

The present article proposes the use of a novel strain measure family, based on the Hyperbolic Sine function and suitable for structural applications. Mathematical expressions for the use of the Hyperbolic Sine strain measure are established following the energetic concepts of the positional formulation of the finite element method.

The purpose of this paper is to describe a wireless strain sensor system which will allow easier collection of accurate strain signals in civil engineering structures. The sensor system is developed by integrating with resistance strain gauge, and the data fusion method is proposed based on batch estimation theory.

The principle of resistance strain gauge is discussed and the project of wireless acquisition system of strain signal is given. Wireless strain sensor is integrated with modularization method. Based on batch estimation theory, the data fusion method of strain signal is described. The experiment of wireless strain sensor system is finished on a typical concrete beam structure, the measure data processed by using the data fusion method and the arithmetic average value method is compared and analyzed.

The research result shows that the wireless strain sensor can be installed easily and thus is applied compatibly to local monitoring in civil engineering. The strain signal processed by the data fusion method is more accurate than the one processed by the arithmetic average value method, and thus the proposed data fusion method is fit for processing such slowly‐changing signals as strain.

In this paper, the innovation is shown from two views: one is applying wireless technique to collect strain signals; another is that data fusion with wide application can make measurements more precise and reliable by eliminating uncertain value than using the arithmetic average value method. In general, the developed wireless sensor system and the proposed data fusion method are fit for local monitoring.

A two‐spar cantilever box beam with forty‐five degrees sweep and oblique ribs placed parallel to the root clamping section was the subject of a series of static tests. Stress and strain distributions were determined, primarily in a region distant from the root and tip disturbances, to permit a stringent comparison with three well‐known swept wing theories and the simple theory of bending. Torsional and flexural stiffnesses were also measured and compared with these theories. The sequence of calculation for each method is presented and it is found that two of the theories provide accurate predictions of the stresses, strains and stiffnesses. The influence of rivet slip and rivet flexibility on the stiffnesses of the box is mentioned. As a secondary aim of the investigation, the distribution of normal and shear strain has been measured in the cover skin and spar webs at the root connexion. The design of swept box examined has been the subject of research in a number of establishments and a review of this other work is included.

DURING recent years strain gauges have been used more and more in the aircraft industry as a means of assessing the loads in aircraft structures, both in structural testing laboratories and in flight. This increased use can be mainly attributed to the satisfactory development of successful electrical strain gauges of the resistance type and to the demand by engineers for a more complete knowledge of the load distribution in modern aircraft structures. Electrical strain gauges, although requiring accurate apparatus and a large amount of electrical wiring in addition, are much more easily attached to the structure than mechanical gauges and have the great advantage that they can be mounted in positions inaccessible to most mechanical gauges. This increased use of such gauges has been applied to the determination of the loads in tubes under combined bending and direct loading and to obtaining the direct and shear stresses in sheets and panels. The results of all this has been that more engineers have had reason to use the basic formulae for determining these quantities from the measured strains on three or more gauge lines.

The paper reports experiments carried out on beams in pure bending. The material used was a cast magnesium alloy AZ855. The beam sections were rectangular, circular, I‐section, T‐scction and diamond. One series of tests was carried out up to 1 per cent fibre strain. A second series of tests was carried out up to fracture. Tension and compression tests were also made on the material. The experimental results show conclusively that the usual theory of plastic bending is correct and that the tension‐compression stress‐strain curve of the material may be used to determine the bending moment‐curvature relationships, etc., for a beam. Measurements of neutral axis shift also confirm the predictions of plastic bending theory.

Safety analysis has been done for thermal non-homogeneous thick-walled circular cylinder under internal and external pressure. The paper aims to discuss these issues.

Transition theory based on the concept of generalized principal Lebesgue strain measure has been used which simplifies the constitutive equations by prescribing a priory the order of the measure of deformation and helps to achieve better agreement between the theoretical and experimental results.

From the analysis, the paper can conclude that by introducing a suitably chosen temperature gradient, non-homogeneous compressible circular cylinder with internal and external pressure for non-linear measure is on the safer side of the design as compared to the cylinder without temperature because circumferential stresses are less for cylinder with temperature as compared to cylinder without temperature.

Introduction of temperature gradient leads to the idea of “Stress Saving” and minimizing the possibility of fracture of cylinder.

The paper shows that circumferential stresses are less for cylinder with temperature gradient as compared to cylinder at constant temperature, which leads to the idea of “Stress Saving” and minimizing the possibility of fracture of cylinder.

The London Interbank Offered Rate (LIBOR) is considered to be the most important interest rate in finance upon which trillions in financial contracts are decided. In 2008, it was revealed that the LIBOR traders were rigging the interest rates. Yet, there is an unresolved question that regulators and banking officials did not address in their quest to seek answers to the fraud: Were the banks under financial strain when they underreported their LIBOR rates? To answer this question, the article posits that the pressure to meet market expectations led the banks to experience financial strain. Data were gathered from 2004 to 2008 on the banks that were involved in the fraud (fraud banks) and matched with a control group of non-fraud banks. The results from a logistic regression model found sufficient statistical evidence to support the claim that fraud will be greater in banks characterized by a higher level of organizational complexity. Variables such as percent of outside directors, board members on the audit committee, and number of employees were all found to be statistically significant. These variables may offer key insights into detecting and preventing frauds in banks.

The preponderance of studies that rely on self-report for both independent (e.g. stressors) and dependent (e.g. well-being) variables is often deplored, as it creates problems of common method variance, which may lead to inflated, or even spurious, correlations and predictions. It is sometimes suggested that alternative measures should yield more “objective” information on the phenomena under investigation. We discuss this issue with regard to: (a) observational measures of working conditions; (b) physiological measures of strain; and (c) event-based “self-observation” on a micro-level. We argue that these methods are not necessarily “objective.” Like self-report, they are influenced by a plethora of factors; and measurement artifacts can easily be produced. All this can make their interpretation quite difficult, and the conclusion that lack of convergence with self-report automatically invalidates self-report is not necessarily warranted. Especially with regard to physiological measures, one has to keep in mind that they refer to a different response level that follows its own laws and is only loosely coupled with psychological responses. Therefore, replacement is not a promising way to get more reliable estimates of stressor-strain relationships. We argue instead that each method contains both substantive and error variance, and that a combination of various methods seems more auspicious. After discussing advantages and pitfalls of observational, physiological, and self-observational measures, respectively, we report empirical examples from our own research on each of these methods, which are meant to illustrate both the advantages and the problems associated with them. They strengthen the overall conclusion that there is no “substitute” for self-report (which often is necessary to be able to interpret data from other methods, most notably physiological ones). They also illustrate that collecting such data is quite cumbersome, and that a number of conditions have to be carefully considered before using them, and we report some problems we encountered in this research. Altogether, we conclude that self-report measures, if carefully constructed, are better than their reputation, but that the optimal way is to complement them with other measures.

The purpose of this paper is to develop a wireless strain sensor for measuring large strains. The sensor is based on passive ultra high‐frequency radio frequency identification (RFID) technology and it can be embedded into a variety of structures.

Silver ink conductors and RFID tags were printed by the screen printing method on stretchable polyvinyl chloride and fabric substrates. The development of the strain‐sensitive RFID tag was based on the behavior of the selected antenna and substrate materials. Performance of the tags and the effect of mechanical strain on tag functioning were examined.

The results showed that large displacements can be successfully measured wirelessly using a stretchable RFID tag as a strain‐sensitive structure. The behavior of the tag can be modified by selection of the material.

New tag designs, which are more sensitive to small levels of strain and which have a linear response will be the subject for future work. Tag performance under cyclic loading and in a real environment will also be investigated. Future work relating the investigation of practical applications and the system designing for the strain sensor will also be required.

Printing is fast and simple manufacturing process which does not produce much waste or material loss. The sensor is a new application of printed electronics. It also provides new opportunities for system designers.

The paper provides a new kind of wireless strain sensor which can be integrated into many structures (i.e. clothes). The sensor is a new application of printed electronics and it is made from novel materials.

There is a large literature devoted to the stresses and strains of work and work‐related activities. This research effort shows no sign of abating. The aim of this paper is to highlight and discuss several centrally important questions and assumptions in the nature of this research which, in our view, require more careful consideration in future work.