A NOVEL TIE POINT BASED STRATEGY FOR POINT CLOUD AND IMAGERY DATA FINE REGISTRATION

Laser scanner generated point cloud and photogrammetric imagery are complimentary data for many applications and services. Misalignment between imagery and point cloud data is a common problem, which causes to inaccurate products and procedures. In this paper, a novel strategy is proposed for coarse to fine registration between close-range imagery and terrestrial laser scanner point cloud data. In such a case, tie points are extracted and matched from photogrammetric imagery and preprocessing is applied on generated tie points to eliminate non-robust ones. At that time, for every tie point, two neighbor pixels are selected and matched in all overlapped images. After that, coarse interior orientation parameters (IOPs) and exterior orientation parameters (EOPs) of the images are employed to reconstruct object space points of the tie point and its two neighbor pixels. Then, corresponding nearest points to the object space photogrammetric points are estimated in the point cloud data. Estimated three point cloud points are used to calculate a plane and its normal vector. Theoretically, every object space tie point should be located on the aforementioned plane, which is used as conditional equation alongside the collinearity equation to fine register the photogrammetric imagery network. Attained root mean square error (RMSE) results on check points, have been shown less than 2.3 pixels, which shows the accuracy, completeness and robustness of the proposed method.

The Bayesian Forecasting of the Bridge Deflection Based on Constant Mean Discount Model

Subject to various factors under loading, bridges appear to be discrete. Thus, it is unavoidable to take the practical bridge into consideration with regard to the bridge deflection forecasting. Given this, the Bayesian dynamic forecasting theory is introduced to forecast the bridge deflection. Since the bridge deflection can stay stable in a long term, create constant mean discount Bayesian conditional equation and observational equation and deduce the Bayesian posterior probability of the bridge deflection conditional parameters on the basis of the prior information of the parameters. With recursive deduction, the conditional parameters keep updating as observational data are imported. The results of Bayesian forecasting comprise values and confidence interval, which makes it more instructive. Finally, practical examples are adopted to examine the superior performance of Bayesian dynamic forecasting theory.

Program Design of Leveling-Network Conditional Adjustment Based on Transferring Matrix

In a complicated leveling-network, it was often simple to write manually the equations to express all the condition that must be met for a conditional adjustment. Therefore conditional adjustment which was straightforward and regularity in its development and solution.was early becoming very popular . But with the advent of the computer technology, it was gradually reducing its effects which was not well suited to computers for its equations not unique and shapes diversity. Based on this, an available leveling-network conditional adjustment program was developed to solve the problem of conditional diversity. By aid of transferring matrix, the program design scheme of the conditional adjustment was proposed by means of visual basic language platform. The coefficient matrix of the conditional equations was written out based on transferring vectors and arithmetic rules. The normal equations were solved by method from Guassian main column eliminated. The Residuals and the measuring precision was achieved by the results from the normal equation back substituted to conditional equation. The application shows that conditional adjustment by transmitting matrix can simplify procedure of writing the conditional equations, and easily program for conditional adjustment.

Moving Performance of Crawler Driven ROV on the Inclined Sea Bottom

The crawler driven ROV is considered as one of the probable systems for seafloor exploration or seabed resources development [1][2][3][4]. However the movability of crawler driven ROV on the sea bottom is not explained clearly compared with the ones on the land [5][6][7][8][9]. The experimental investigation on the crawler based ROV’s movability suggests that light weight ROV are easy to run in bow up condition and sometimes are possible to turn over. Therefore it is important to make it clear what kind of condition is to be satisfied for the normal run when the ROV moves on the sea bottom with crawlers. In this study, a simple dynamic model for the ROV which runs steadily on the inclined smooth sea bottom has been developed and the condition which should be satisfied for normal running has been derived. We consider that the forces acting on ROV are gravity, buoyancy, reaction from sea bottom, thrust and hydrodynamic resistance and treat them as concentrated loads. From the balance condition of forces for longitudinal and vertical direction and pitching moment, three kinds of relation are obtained. We consider that force reaction point from sea bottom should be inside between the fore and rear wheels for the normal operation. With this condition, the relation to be satisfied between the location of gravity center and center of buoyancy is obtained. To validate this conditional equation, the model experiments are carried out. The ROV model contains several weights and floating materials so that the longitudinal center of gravity and buoyancy can be changed by moving the weights and floats. Changing the longitudinal location of buoyancy center of the model from backward to forward, the limiting normal running condition for each longitudinal location of gravity center are measured. The obtained experimental results agree well with the theoretical ones. The presented conditional equation to be satisfied for normal running is considered to support the basic planning of a crawler driven ROV.

Determination of inspection schedules of equipment by variational method

Maintained equipment can be subject to random failures. If failures are evident, they can be detected immediately when they occur. On the other hand, hidden failures that are not revealed during the performance of regular duties may be detected by inspection process. If concerned equipment has hidden failures, loss is assumed to incur from the moment its failure until the time when it is detected. Optimal inspection schedule should be considered when inspection is costly. In this study, optimal inspection schedules for equipment are derived by the variational method employing the inspection density function. For the case in which the time-to-failure distribution of equipment is given, a conditional equation that optimal inspection schedules should satisfy is derived. Furthermore, when the time-to-failure distribution is unknown, an ordinary differential equation that optimal inspection schedules should satisfy is obtained. Optimal inspection schedules in a closed form and numerical examples are shown for some potential loss rate functions.

Unemployment and Profitability in Spain

This paper explores empirically the relationship between the high and persistent unemployment in Spain and the profitability on invested capital. It is shown that there exists a negative long-run relationship between the two variables, an unemployment-profit rate trade-off (UPRT). A conditional equation with constant parameters relating the unemployment rate to the profit and capacity utilization rates is derived. Exogeneity tests indicate that profit rate and capacity of utilization are weak, strong, and super exogenous for the parameters of the unemployment equation.

A new isothermal theory for Stirling machine analysis and a volume optimization using the concept of ‘ancillary’ and ‘tidal’ domains

Theoretical studies of Stirling cycle machines have always utilized a topological system view that goes back to Schmidt's isothermal analysis, where the process is analysed by reference to the expansion space volume variations. Due to this idiosyncrasy in the formulation, it has been difficult to deduce meaningful design criteria from the results. In this paper an alternative visualization is presented, using the newly introduced concepts of a ‘tidal phase angle’ and overlapping ‘tidal’ and ‘ancillary’ domains. With vectorial parameters and a centralized reference basis, a non-dimensional parameter Rcaronfr;tcr, the ‘tidal compression ratio’, equal to the ratio of the average masses in the tidal and ancillary domains, is derived. This number uniquely characterizes the operation of equivalent machines and is therefore akin to the compression ratio in internal combustion engines. On the basis of this, a second new parametric grouping emerged to enhance the usefulness of the resultant integrated equations for use with dimensional analysis. It was defined as the ‘specific performance’ Rcaronfr;sp and is proportional to the output per unit mass, the gas constant and the operating temperature range. It is applicable to engines, heat pumps and refrigerators. Prior attempts at optimizing the proportions of a Stirling engine have not yielded usable results and consequently nearly all Stirling cycle machines built up to the present time have expansion and compression spaces of equal size. The new analysis shows that this is not the most appropriate configuration and it readily yields an optimization of the component volumes. One single analytical conditional equation for the optimum relative sizes of the constituent spaces was obtained from the new formulation for performance that quantifies the condition for an optimized proportioning of any Stirling cycle machine. It has three distinct usable solutions, one of which is an analytical confirmation of a postulate that has previously been published by the author without proof, equating VE/ VC and also Vh/ Vk to the temperature ratio TE/ TC. A numerical verification of this rule based on the proportions of the United Stirling V-160 engine compares it with 12 equivalent re-proportioned derivative engines, all with equal charge masses and operating at precisely the same conditions. This shows a substantial increase in the ideal performance through the use of the derived criteria. The main conclusion is that this theory may lead to a re-examination of the overall layout of Stirling cycle machines and the emergence of a new class of machines with superior performance.

A new method of analysis and reduction of VLBI observations

In this paper we develope an inertia! system of coordinates introducing a new observable: the arc between a pair of radio sources. We shall discuss how the conditional equation involving all the parameters is written in diferent systems when the observations are performed with a two and a three-element interferometers.