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The purpose of this paper is to solve the problem that the relationship between loading forces, which were applied at different positions on a plane, and output values of load-sharing dynamometer is non-linear.

First, the analytical model of ISPM (isodynamic surface proportional mapping method) method, which is used to calibrate dynamometer, was established. Then, a series of axial force calibration tests were performed on a load-sharing dynamometer at different loading positions. Finally, according to output values, calibration forces at different loading positions were calculated by ISPM method, and corresponding distribution histogram of calibration force error was generated.

The largest error between calculated force and standard force is 2.92 per cent, and the probability of calculated force error within 1 per cent is 91.03 per cent, which verify that the ISPM method is reliable for non-linear calibration of dynamometers.

The proposed ISPM method can achieve non-linear calibration between measured force and output signal of load-sharing dynamometer at different positions. In addition, ISPM method can also solve some complex non-linear problems, such as prediction of plane cutting force under the influence of multiple parameters, the force measurement of multi-degree-of-freedom platform and so on.

Disputes are now considered endemic in the construction industry. They often arise from the poor resolution of claims in the course of construction projects. Efforts have been geared towards reducing the incidence of claims. These efforts are of two kinds: those that seek answers from basic principles and legal issues at the pre‐construction phase and those that attempt to solve the problems through claims management procedures at the construction phase. This paper reviews the developments in claims management and highlights the deficiencies in current claims management approaches. It focuses on the need for improvement of the efficiency of claims negotiation and suggests the use of multiagent systems as an approach to achieve it. The potential benefits of the suggested approach are discussed in the concluding section of the paper.

This paper presents a model for the simulation of dynamic behaviours of a coupled magneto‐mechanical system. The magnetic equation is solved with the help of the finite element method. The local magnetic material saturation is considered. The moving band technique is used for accounting the movement. The magnetic torque of permanent magnet synchronous machine is calculated from the field solution according to virtual work principle and then introduced in the mechanical motion equation to calculate the shaft position. The complete differential equation system is solved with an iterative procedure.

In the applications of FEM. a compromise between the accuracy and the computation cost is often required, especially when 3D cases are concerned Adaptive mesh refinement is a good answer to this demand.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

Several second order edge elements have been applied to solving magnetostatic problems. The performances of these elements are compared through an example of magnetic circuit. In order to ensure the compatibility of the system equations and hence the convergence, the current density is represented by the curl of a source field. This avoids an explicit gauge condition which is cumbersome in the case of high order elements.

The purpose of this paper is to solve the problem that the analytic solution model of spatial three-dimensional coordinate measuring system based on dual-position sensitive detector (PSD) is complex and its precision is not high.

A new three-dimensional coordinate measurement algorithm by optimizing back propagation (BP) neural network based on genetic algorithm (GA) is proposed. The mapping relation between three-dimensional coordinates of space points in the world coordinate system and light spot coordinates formed on dual-PSD has been built and applied to the prediction of three-dimensional coordinates of space points.

The average measurement error of three-dimensional coordinates of space points at three-dimensional coordinate measuring system based on dual-PSD based on GA-BP neural network is relatively small. This method does not require considering the lens distortion and the non-linearity of PSD. It has simple structure and high precision and is suitable for three-dimensional coordinate measurement of space points.

A new three-dimensional coordinate measurement algorithm by optimizing BP neural network based on GA is proposed to predict three-dimensional coordinates of space points formed on three-dimensional coordinate measuring system based on dual-PSD.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

This chapter estimates how minimum parking requirements increase the cost of constructing housing, office buildings, and shopping centers. It also explains proposed legislation to limit how much parking cities can require in transit-rich districts.

I assembled data on the cost of constructing office buildings, shopping centers, and parking spaces in eight American cities, and data on the minimum parking requirements in these cities. I then combined the parking construction costs with the number of required parking spaces for each land use to estimate how the minimum parking requirements increase development costs for office buildings and shopping centers.

Minimum parking requirements increase the cost of constructing a shopping center by up to 67 percent if the parking is in an aboveground structure and by up to 93 percent if the parking is underground.

In suburban Seattle, parking requirements force developers to spend between $10,000 and $14,000 per dwelling to provide unused parking spaces.

On a typical construction site in Los Angeles, parking requirements reduce the number of units in an apartment building by 13 percent.

To mitigate the high costs imposed by minimum parking requirements, California is considering legislation to set an upper limit on how much parking cities can require in transit-rich districts: no more than one space per dwelling unit or two spaces per 1,000 square feet (93 square meters) of commercial space. This legislation would limit parking requirements, but it would not limit the parking supply because developers can always provide more than the required number of spaces if they think demand justifies the added cost.

This chapter measures how minimum parking requirements increase the cost of housing, office buildings, and shopping centers in order to subsidize parking. Urban historians often say that cars have changed the city, but urban planning has also changed the city to favor cars.