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The pattern of provincial economic integration in a country can be well measured by the error-components model, which enables us to attribute the variation of real output growth to factors that are industry specific and those that are province specific. Usually, the error-components model equation is solved by the dummy variable regression method. This paper presents an alternative approach, that is, the least square method, which can solve the error components model equation effectively. The presented approach is validated by its application to study the pattern of provincial economic integration in China for the period 1996-2004.

The goal of this study is to improve the accuracy of mobile node localization and to avoid the influence of moving direction-offsets introduced by the positioning system’s accuracy control. The proposed localization algorithm, which is based on an overlap self-adjustment method, and an anchor node selection mechanism which uses the Gaussian elimination method, is based on the error probability. The proposed algorithm has the advantages of requiring little prior information, and it reduces the power consumption. The simulation results show that the proposed algorithm is better than the self-adjustment localization (SAL) algorithm in terms of its localization accuracy.

This paper presents a low-order and accurate method for the design of FIR fractional delay (FD) filters with complex coefficients. This method employs least square technique in Hilbert space to approximate the ideal FD transfer function with a FIR filter and to calculate its coefficients. The main advantages of the resulting filter are: very good response at all frequencies compared to other FD filter design methods and a good method to create very small delay. Design examples are presented to illustrate the effectiveness of this new design approach.

We will develop an efficient method for estimating a smooth nonnegative forward rate sequence using the market price of riskless bonds. This method is an improvement of the classical Carleton–Cooper's method based on standard least square method, which often generates a non-smooth forward rate sequence and hence is not used in practice. The method to be proposed in this paper is intended to resolve this difficulty. We will impose a smoothness condition while maintaining the fitting error within an acceptable level. The resulting optimization problem is shown to be convex in the region of interest. Therefore, we can calculate a globally optimal solution very fast by standard nonlinear programming algorithms. We will demonstrate that this method generates a smooth forward rate sequence at the expense of a very small increase of fitting error.

In this work, we aim to solve the multi-warping document image problems. We can overcome the limitations of the previous dewarping algorithms to recover the shape of the document. The proposed method is based on a well-defined pattern to simulate the distorted and undistorted connected component of document images. Some pairs of control points are selected for each connected component and its ground truth pattern to define the mapping function between them. The dewarping process transforms the warping connected component according to the geometric transformation defined by the calculated mapping function. Results on document dewarping dataset CBDAR demonstrate the effectiveness of our method. OCR error metrics are also used to evaluate the performance of the proposed approach.

In this paper, Golden Ratio Simulated Annealing (GRSA) for Protein Folding Problem (PFP) is presented. GRSA is similar to Multiquenching Annealing (MQA) and Threshold Temperature Simulated Annealing (TTSA) algorithms. In contrast to MQA and TTSA, GRSA uses several strategies in order to reduce the execution time for finding the best solution of PFP. Firstly, temperature parameters are tuned with an analytical-experimental approach; secondly, a heuristic technique for dividing the search space is implemented. GRSA has a special phase which detects the thermal equilibrium by a least squares method. In addition, a reheat strategy to escape from local optima is applied.

Based on the crash test of new energy vehicles, the mechanical response data of power batteries during the collision process were collected, and the average impact strength curve of power batteries of typical new energy vehicles in China was obtained. The average impact strength curve was mathematically processed to obtain the impact strength characteristic value and tolerance by using the equivalent trapezoidal wave and the least square method, thereby determining the test conditions of the dynamic strength of the domestic new energy vehicle power battery. The differences are analyzed by comparing with ISO 12405-3 test conditions, which provides an important reference for the revision of power battery test standards in the future.

For a growing range of optical measurement task, like gap measurement in automotive industry, traditional triangulation sensors have several disadvantages due to the fact that the measurement result is dependent on the orientation of the sensor because of the non-rotational symmetry of the optics. Consequently a design method was proposed recently for a new class of rotationally symmetric triangulation sensors. Such designs can be realized with aspheric reflection optics and area detectors, such as CCD or CMOS. The optics of the sensor can be extended by an imaging optics which allows at the same time image capturing and distance measurement. In this paper we show the first prototype. This system is based on an optical system of one part manufactured by commercially available diamond turning. The layout of the optical system for distance measurement consists of two reflecting aspheric surfaces.

The high precision algorithm for ring location was needed because the performance of the sensor is based on the detection of ring, especially the radius of the ring. In this paper, we try to give the different evaluation function for high precision location of ring. Then we used various methods to solve it and got optimized result. The comparison of algorithms for simulation was listed in the paper. And the measurement result for the real image got by the prototype was also presented. It seems the algorithm meets the precision demand of the sensor.

In intelligent vehicle system, it is significant to detect and identify road markings for vehicles to follow traffic regulation. This paper proposes a method to recognize direction markings on road surface, which is on the basis of detected lanes and uses Hu moments. First of all, the detection of lanes is based on horizontal luminance difference, which converts the RGB color image to the luminance image, calculates the horizontal luminance difference, obtains the candidate points of lanes' edge and uses least square method to fit the lanes. Secondly, with the detected lines as guide for the search of candidate marking, the paper extracts Hu moments of candidate marking, calculates its Mahalanobis distance to every marking type and classifies it to the type which has the minimal distance with the candidate marking. From the simulation results, the method to detect lanes is more effective and time-efficient than canny or sobel edge detection methods; the method to recognize direction marking is effective and has a high accuracy.

At the time of re-entry modules entering into the atmosphere from space, a small perturbation introduces dynamic oscillations on the vehicle because of their extreme traveling speed. The dynamic stability characteristics of re-entry modules at hypersonic Mach numbers is of considerable relevance to their initial design. In the present paper, the dynamic stability of blunt cone model about $10^{\circ }$ is examined with wide range of design parameters such as nose bluntness, semi-vertex angle and center of rotation through theoretical and experimental methods. Theoretical approximations are made over a model based on the standard Newtonian theory. Experiments are conducted at $0.25\mathrm{\text{m}}$ hypersonic wind tunnel at $M=8.3$ and the following trends are observed from the experimental analysis. Interestingly, the incremental higher nose bluntness, semi-vertex angle and center of rotation reduce the dynamic stability. At higher hypersonic Mach numbers $(M>10)$, dynamic stability characteristics of the re-entry module are insensitive to the free stream Mach number. However, it is observed that the dynamic stability is increased in proportion to the vibration amplitude at hypersonic speeds.

According to the feature of Buddha’s head light and backlight area is circle in Thangka image, so a method is proposed for detection of circle head light and backlight. Firstly, a method of morphology in edge extraction to get image edge is used, and by removing the edge connection point to get edge segment image. Secondly, through least square circle detection and verification condition of target circle to get the precise position of circle head light and backlight in Thangka image. The experimental results show that the method is with high accuracy and accurate positioning features in the detection of Buddha’s circle head light and backlight in Thangka Image.

In order overcome the defect of passive control of oleo-pneumatic shock absorbers, a new structure of magnetorheological shock absorber is proposed. Its damper characteristics are test by vibration test bench, and its damper model is built by the method nonlinear hysteretic biviscous damper model. The parameters of damper model are identified by least square method. The damper model can effectively characterize the intrinsic nonlinear behavior of shock absorber. Compared with the results of experiment, the maximum of relative error of damper is less than 13%.

Aiming at the requirement of low-power dissipation, fast-response and high precision temperature measurement for Hydrogeology And Environmental Geology Survey, the High Precision Thermistor Temperature Measurement is developed based on the MSP430F5438 used as the main control chip. The thermistor is driven by the Voltage-controlled constant current source, and the output signal is collected by the 12 high resolution ADC module on the MSP430F5438 processor. Meanwhile, the least square method is used to deal with the thermistor nolinear, so that the temperature is measured accurately. It is indicated that high accuracy of ±0.02℃ in the range of -10~50℃ can be achieved and the measurement system has board prospects in application with the advantage of low-power dissipation, simple structure and high reliability.