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This paper aims to investigate the equivalent relationship between accelerated corrosion tests and real environmental spectrum of suspenders in long-span suspension bridge considering multiple factors action.

Based on Faraday's law, corrosion current was used as a measure of metal corrosion, and the equivalent conversion relationship between laboratory environment and real service environment was established. The equivalent conversion method for bridge structural steel had been determined under different temperature, humidity, pH value and NaCl concentration conditions. The compilation of environmental spectra for large span bridges considering multiple factors and the principle of equivalent conversion have been proposed.

Environmental factors, including temperature, humidity, pH value and NaCl concentration, have significant impact on the corrosion degree of suspension steel wires, and only considering these two factors for equivalent conversion cannot accurately reflect the true service environment of the bridge. The 33.8-h salt spray accelerated corrosion test using the standard conditions can be equivalent to one year of suspenders corrosion in a real service environment.

The equivalent accelerated corrosion method for steel wires proposed in this study can effectively predict the corrosion degree of the suspenders, which has been verified to be correct and can provide theoretical guidance for the development of corrosion test plans for steel wires and engineering technical basis for anti-corrosion control and calendar life research of suspension bridge suspenders.

This paper aims to research steel wire corrosion pitting distribution characteristics and evolution, the shape, number and size of corrosion pits from one tied arch bridge were tested, analyzed and researched.

The probability distribution model of corrosion pits of different shapes was established, and the law of corrosion pit growth and evolution was researched. The relationship between the steel wire local corrosion parameters and the average degree of corrosion was explored.

The results revealed that the pits of steel wires can be divided into four categories of shapes: a deep ellipsoidal shape, a shallow ellipsoidal shape, a groove shape and a saddle shape. When developing to a certain degree, the small dark narrow type corrosion pit will turn into a large open pit of either a shallow ellipsoidal shape, a groove shape or a saddle shape.

The maximum depth of the corrosion pits was close to the Weibull distribution, and the maximum width and length of the wire corrosion pits were close to the logarithmic normal distribution, causing a large error when using a uniform corrosion model of steel wire mechanics.

A pooled income fund (PIF) is one of the methods created under the 1969 Tax Reform Act whereby a taxpayer may make a tax‐deductible remainder gift to a charitable organization. The fund, established by a charitable organization to receive irrevocable gifts from at least two donors, pays current income to the individual beneficiaries for life, but at the termination of each income interest, the allocable principal must revert permanently to the charitable organization. In recent years, a number of PIFs have been offered to the public by charitable organizations through broker‐dealers or related entities. There are numerous securities‐law issues implicated by the sales of these PIFs, including: (i) whether broker‐dealers may solicit donations to such funds and receive compensation for their solicitations; (ii) the effect of the broker‐dealers’ solicitation and receipt of compensation have on securities registration for the PIF or units offered therein under the Securities Act of 1933, the Securities Exchange Act of 1934, or the Investment Company Act of 1940; (iii) whether staff and persons affiliated with the sponsoring charity, including parties assisting them in the marketing of such pooled income funds, also should be permitted to solicit donations; (iv) whether such charities or persons, or parties assisting them in the marketing of such pooled income funds, then should be required to register as broker‐dealers; (v) what securities licenses may be required of the aforementioned parties; and (vi) whether there are ways to design the manner in which third parties other than broker dealers are compensated to resolve any potential issues arising from answers to the previous questions. This article first sets forth the applicable law involved in the analysis and then attempts to answer each of the issues presented above.

The purpose of this paper is to analyze the cable-supported bridges more efficiently by building the finite element model with the spatial combined cable element.

The spatial combined cable element with rigid arms and elastic segments was derived. By using the analytical solution of the elastic catenary to establish the flexibility matrix at the end of the cable segment and adding it to the flexibility matrix at the ends of the two elastic segments, the flexibility matrix at the end of the cable body is obtained. Then the stiffness matrix of the cable body is established and the end force vector of cable body is given. Using the displacement transformation relationship between the two ends of the rigid arm, the stiffness matrix of the combined cable element is derived. By assigning zero to the length of the elastic segment(s) or/and the rigid arm(s), many subdivisions of the combined cable element can be obtained, even the elastic catenary element.

The examples in this field and specially designed examples proved the correctness of the proposed spatial combined cable element.

The combined cable element proposed in this study can be used for the design and analysis of cable-stayed bridges. Case studies show that it is able to simulate cable accurately and could also be used to simulate the suspenders in arch bridges as well in suspension bridges.

The constant battle to resist the corrosion of the structural steelwork of a bridge commences even before its erection, and must continue relentlessly throughout the life of the structure. This has been the case with the San Francisco‐Oakland Bay Bridge where the painted surface area of 370 acres extends from a height of 6 ft. above high water to 530 ft. above the water at the top of aircraft warning beacons on the suspension bridge towers.

Anti‐corrosive primer. One of the new Five Star Range of resin based products announced by the Boston Chemicals Ltd, Wetherby, West Yorks LS23 7BZ, is an anti‐corrosive primer. This is a water thinnable acrylic, anti‐corrosive primer containing a zinc phosphate. It does not contain any toxic pigments.

Multisited ethnography has primarily been portrayed as a challenge for the following field-worker, with the researcher taking the central role and neglecting research participants also experiencing a multisited nature of their work. The authors argue that literature on multisited ethnography merely discusses multisitedness as a methodological theme. In correspondence, the authors propose to think of multisitedness not just as a methodological theme but also as an empirical theme.

The authors contend etic and emic perspectives to address multisitedness empirically, which enables researchers to compare and contrast the multisited topic of inquiry in academic “outsider” terms with the etic analysis and considering the perspective of the research participants' multisited experiences using the emic perspective. To show the fruitfulness of discussing multisitedness using the complementary etic and emic analysis, the authors present the example of Mennonite entrepreneurial activities in Belize, a heterogeneous group of migrants that established themselves as successful traders and entrepreneurs.

Through an etic multisited ethnographic perspective, the authors compare and contrast four communities of Mennonites in terms of their entrepreneurial activities, technology and energy use. Through an emic perspective, the authors demonstrate how Mennonites, while preferring an in-group focus, navigate their multisited entrepreneurial activities, which require interaction with the outside world.

The authors highlight the value of combining etic–emic reflections to acknowledge and include the multisited nature of many social phenomena as experienced by the research participants.

Several studies have aimed to develop robotic systems which move in transmission lines. Until this moment, all of them have a high weight and cost associated with the equipment and reduced battery autonomy time. In this context, this paper aims to propose the POLIBOT (POwer Lines Inspection roBOT) with low cost and weight, enabling the movement over the lines and an easier installation and remove.

The designed robot uses the Profiles Manufacturing Methodology (PMM). The construction of the robot mechanical structure uses modularized aluminum parts built through square profiles. Thus, it’s possible a drastic reduction in production time as well as cost reduction and weight when comparing this method with other manufacturing processes like foundry, for example. For hardware and software systems, the use of free and open source software causes a significant reduction in cost and project execution time. The benefits of using open source systems are immeasurable, both from academic and industrial applications.

The POLIBOT platform is one solution to the problem of inspection in power lines. With this robot, more lines are maintained with lower time. In its constructive aspect, the robotic mechanism is designed using principles of bioengineering. The use of this principle was successful, considering that obstacle transposition is performed with stability and low energy consumption.

The suggestion for future researches is to replace the battery for solar energy and construction in polymeric material to avoid high magnetic fields.

The commercial application is evident because manual inspections are inefficient, very expensive and dangerous. Thus, it is growing the number of researches that develop mechatronics systems for this kind of inspection.

The impact is the reduction of accidents because the present procedure requires precision of movements, where the pilot and electrical technician are close to high electrical and magnetic fields. In addition, for some tasks, the worker has to walk on the line to reach some important points. Thus, those tasks involve high risk of death.

The PMM methodology represents an innovation to the state of the art because others robotic mechanisms proposed for inspection tasks present total structure mass between 50 and 100 kg and POLIBOT has only 9 kg. Other fact is its price for implementation as this robot used the robot operating system (ROS) framework, what dispense the use of licenses. Other important features are that the robot performs the tasks autonomously, which reduces errors introduced by the operator and its low manufacturing cost as compared with other projects.

The purpose of this paper is to identify the challenging barriers faced by female firefighters, which limit workplace entrance and performance.

Occupational barriers from both psychological and physiological viewpoints were explored based on previous literature and the reported experiences of female firefighters.

A comprehensive review of literature synthesizes previous studies pertaining to gender anthropometric differences, female firefighters’ experiences in the work environment and protective clothing issues. The physical capabilities of men and women in specific relation to performing firefighting activities are also examined. Issues of greatest concern are identified for personal protective clothing (PPC) and equipment, which have traditionally been designed for the male human form. This leads to a lack of protection, an increased risk of onsite injury, reduction in mobility and poorer comfort for female firefighters.

This review provides an original overview of the critical workplace challenges faced by female firefighters. The need for female-specific PPC and equipment is specifically addressed to retain the growing number of women entering the male-dominated firefighting profession.

In an aircraft having adjustable pitch propellers with pitch control shafts projecting therefrom, means for simultaneously rotating said shafts either similarly or oppositely as desired comprising : a wheel carried by each of said shafts ; a tiltable pulley head ; a pair of end pulleys at each extremity of said head ; a pair of middle pulleys at the axis of said head ; an endless flexible medium trained about said wheels and about all of said pulleys so that when said head is tilted in one direction, it will rotate said control shafts oppositely, and when said middle pulleys alone arc rotated they will rotate said control shafts similarly ; and means for rotating said middle pulleys.