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南海某油田防垢剂筛选与性能评价
The Selection and Performance Evaluation of the Scale Inhibitor for a Nanhai Oilfield
 [PDF]

张浩,
Hans Journal of Chemical Engineering and Technology (HJCET) , 2015, DOI: 10.12677/HJCET.2015.53008
Abstract:
针对南海某油田生产水回注存在的结垢问题,本文作者通过室内模拟水用沉淀重量法考察了几种防垢剂的防垢效果。在90℃作用24小时条件下,防垢剂HYFC-027、HYFC-074、YFFG-037具有较优的防垢效率,在加药浓度30 mg/L时,防垢率可以达到85%以上。通过自腐蚀实验和老化试验,三种防垢剂防垢效果稳定,尤其是对204不锈钢材质没有腐蚀现象。
Refer to the scaling issue that is caused by produced water reinjection in an oilfield in South China Sea, the effects of several scale inhibitors have been examined by the precipitation gravimetric method using indoor simulated water. Under the conditions of 90?C for 24 hours, scale inhibitor HYFC-027, HYFC-074, YFFG-037 have better scale efficiency. When the dosing concentration is 30 mg/L, the scale rate can reach 85%. By corrosion experiments and aging tests, all three scale in-hibitors are stable and have no corrosion phenomenon, especially for the 204 stainless steel.
一维双基线相位干涉测向公式的准确解
Accurate Solution of DF Formula for Phase Interference with One-Dimensional Double Baseline
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Journal of Antennas (JA) , 2012, DOI: 10.12677/ja.2012.11002
Abstract:

摘  要:在利用径向距离与相位之间的对应关系给出相差定位方程的基础上,应用余弦定理所给出的三角方程,且仅通过简单的数学变形处理即得到了求解目标位置的线性方程组,并由所解得的目标位置获得了一维双基线相位干涉阵列的测向公式准确解。整个分析过程借助于路程差与相位差测量项的等价性,在不涉及对整周数和鉴相电路相位差值计算的情况下,实现了对准确解的验证和测量误差的分析。本文的研究为校正现有按平行入射波假定所得到的近似解的测量精度提供了理论依据。





Abstract: On the basis of the phase-differential locating equation obtained by the correspondence relationship between radial distance and phase, applying the trigonometric equation obtained by cosine law, the set of linear equation solving the target position can be obtained only by simple mathematical manipulation. Now, the location parameter of target can be solved and the accurate DF formula can be derived for the phase interference array with double baseline in one-di- mensional space. The verification for accurate solution and analysis for measuring error can be worked out by using the equivalence between path length difference and phase difference. But also, the analysis process is not related to the integer of wavelength and phase-differential measurement of discriminator. The study in this paper provides a theoretical basis for the correction of the measurement accuracy to the existing approximate solution obtained by the assumption of parallel incident wave.

机载平台相对角速度的相移检测法
Detection Method of Relative Angular Velocity by Measuring Phase-Shift on Airborne Platform
 [PDF]


Journal of Antennas (JA) , 2012, DOI: 10.12677/JA.2012.12004
Abstract:

如对基本测向公式进行微分变形,则即可得到基于频差检测的角速度计算公式。进一步引用相差与频差之间的函数关系,即可将频差检测等效转化为相差检测。模拟计算验证了本文所导出的仅基于相差检测的角速度计算公式的正确性。误差分析则表明,在综合考虑了相差和速度的测量误差之后,具有实时测量性能的新方法可实现小于1 mrad/s的测量精度。

After making the differential transformation for direction finding based on phase interferometry, the formula of angular velocity can be obtained by measuring frequency difference. Further, the measurement for frequency differ- ence can be transformed into phase difference measurement as soon as the function relationship between frequency shift and phase shift is introduced. The analog calculation validates that derived formula only based on phase difference measurement is correctness. The error analysis shows that the new method which has the performance of real-time measurement can achieve the measurement accuracy less than 1 mrad/s after synchronously calculating the measurement error of phase difference and airborne platform flight speed.

 

弧焊机器人运动学分析及笛卡尔空间轨迹规划
Arc Welding Robot Kinematics Analysis and Trajectory Planning in Cartesian Space
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Artificial Intelligence and Robotics Research (AIRR) , 2013, DOI: 10.12677/AIRR.2013.21009
Abstract:
弧焊机器人作为一种典型的6自由度串联机器人,在汽车等行业中发挥着越来越重要的作用。本文以一款自主研发的弧焊机器人为实例,建立D-H坐标系,进行机器人的运动学分析,并在此基础上完成机器人笛卡尔空间的直线和圆弧轨迹规划。编写MFC应用程序,将生成的数据点在Matlab平台上进行绘图,验证理论计算的正确性。
Arc welding robots, as typical 6-DOF serial robots, are gradually playing an important role in the automotive and other industries. In this paper, taking an independently designed arc welding robot as an example, demonstrated the establishment of D-H coordinate system, the robot kinematic analysis, and run a robot Cartesian space of linear and circular trajectory planning based on previous work. Employing a MFC application program, the derivatively generated data points are plotted in the Matlab to verify the correctness of the theoretical calculations.
城乡一体化背景下职业教育存在问题及对策探析
On the Basis of Urban-Rural Integration and Research on Problems and Countermeasures of Vocational Education
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Vocational Education (VE) , 2012, DOI: 10.12677/ve.2012.11001
Abstract:

目前,在我国城乡一体化建设过程中,专业技能型人才需求有很大的缺口,在一定程度上制约了城乡一体化建设的开展,而职业教育是培养技能人才的重要途径,正确指导职业教育的发展对促进我国城乡一体化建设具有非常重大意义。对此,本文探析了城乡一体化建设对职业教育发展的要求以及职业教育存在的问题,并根据城乡一体建设的发展要求提出了职业教育发展的对策,以期职业教育在促进我国城乡一体化建设中发挥更大的作用。
At present, in the process of urban and rural integration, a wide gap of professional skilled per- sonnel, restricting the carrying out of the urban-rural integration, and vocational education is an important way to cultivate skilled personnel, the correct guide on the development of vocational education in promoting the integration of urban and rural areas have very great significance. In this regard, this paper explores the requirements for the development of vocational education and vocational education in urban and rural inte- gration problems, based on the development of integrated urban and rural construction requirements of the proposed countermeasures of the development of vocational education, vocational education in order to promote the integration of urban and rural play a greater role.

虚拟基线的相位跳变及校正
Phase Jump of Virtual Baseline as Well as Correction
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Journal of Antennas (JA) , 2013, DOI: 10.12677/JA.2013.21002
Abstract:

分析发现,在对相邻两基线采用异侧比值相减方式构造虚拟短基线时,在部分的到达角方向上,波长整周数的差值将不为零,而是存有跳变。并且,在利用虚拟短基线的无模糊测向结果求解长基线的相位模糊值的过程中同样存有相位跳变问题。本文的分析表明,通过对到达角的正弦值进行判别即可实现校正,且修正因子即为两基线差值的比例因子。最后通过应用精确测向公式从理论上说明,若不考虑相差测量误差,则通过校正之后,采用一维双基线阵列即能获得较高的测向准确性。

While the virtual short baseline is constructed by using the ratio subtraction in contrary terminal for adjacent two baselines, the differential of wavelength integer is not to zero in some arrival angle direction and but there is a jump. At the same time, there is also jump problem while using the DF result of virtual short baseline without phase ambiguity solves the phase ambiguity valuation of long baseline. The analysis in this paper shows that the emendation can be realized by distinguishing for the sinusoidal valuation of arrival angle. Also, the modifying factor is namely the proportional factor of differential between two baselines. Finally, applying the accurate DF formula explains in theory that higher accuracy of DF can be obtained by using two baselines arrays after revising without considering the phase error.

 



基于精确相差测向的机载多普勒频移计算
Calculating of Airborne Doppler Shift Based on Accurate Phase Difference DF
 [PDF]


Open Journal of Circuits and Systems (OJCS) , 2014, DOI: 10.12677/OJCS.2014.32005
Abstract:

首先描述了利用一维双基阵所导出的精确测向式,然后基于多普勒频移方程,通过简单的角度置换即获得了基于相差测量的频移计算式。和基于相差近似测向式所给出的频移计算式的比较表明,基于精确相差测向式所导出的频移计算式是更为准确的。误差分析表明,当基线长度为几十个波长时,在目标到达角小于40度的范围内,多普勒频移的测量误差可小于5赫兹。
Firstly, the derivation process of an accurate DF formula based on one-dimensional linear array with two baselines is described. Then, the Doppler shift formula based on phase difference measuring is obtained by simple substitution for angle according to Doppler shift equation. As compared with the Doppler shift formula derived from approximative DF formula based on phase difference measuring, the one derived from accurate DF formula is more veracious. Error analysis shows that the measurement error of Doppler shift is less than 5 Hz within arrival angle range  when baseline is about dozens of wavelengths.

机载平台相差变化率的多通道相移检测
Method Obtaining Phase-Difference Rate by Multichannel Phase Difference Detection on Airborne Platform
 [PDF]


Journal of Aerospace Science and Technology (JAST) , 2013, DOI: 10.12677/JAST.2013.11001
Abstract:
基于相移与频移间的函数关系,提出了一种通过多通道相移测量获得机载平台相差变化率的新方法。首先,利用在由相位干涉测向所给出的到达角与在多普勒频移方程中所包含的前置角之间的互余关系,描述了频移的相差检测方法。然后进一步通过对距离相差方程的微分导出了相差变化率的多通道相差检测方法,并同时亦从理论上证明了相位变化率是可通过测频而获得。在此基础上,由相差变化率测距的方法间接验证了基于多通道相差测量的相差变化率的计算公式的正确性。尽管误差分析表明基于多通道相差测量所获得的相差变化率的测量精度还较差,但与通过双通道鉴相测频获取相位差变化率的测量方法相比,多通道相差检测可避免因被测量的频差间隔值太小,等效测量时间很短,使测量误差变得很大的问题。同时,多通道相差检测的优点还在于一次测量即可实时获得相差变化率,因无需通过延长观察时间来积累足够的相位差序列的长度,故无需限定载机的运动速度。
Based on the function relationship between phase shift and Doppler shift, this paper presents a new method obtained the phase-difference rate on airborne platform by measuring the phase shift in multichannel way. Firstly, the method that detects Doppler shift by measuring phase difference is described by making use of the mutually complementary relationship between the arrival angles obtained by direction finding based on phase interferometer and advance angle contained in Doppler shift equation. Further, the method detecting phase difference rate based on phase difference measurement is derived by differential for distance-phase difference equation. Meanwhile, it also proves theoretically that the phase difference rate can be obtained by frequency measurement. On this basis, according to the ranging method based on phase difference rate, this paper indirectly verified the correctness of the phase difference rate formula obtained based on the multi-channel phase difference measurement. Although the error analysis shows that the measurement accuracy obtained based on the multi-channel phase difference measurement is poor, multichannel phase detection can avoid the problem making measurement error worse since the space value of measured frequency difference is little and equivalent measuring time is shorter as compared with the measurement method of phase difference rate obtained by the frequency measurement based on two-channel phase demodulation. At the same time, because the phase difference rate can be obtained by single measurement in real time and the system dispenses with accumulating the adequate length of phase difference sequence by prolonging viewing time, there is no need to restrict the aircraft moving speed.
运动平台上时差变化率的相差检测
Detection for Time Difference Rate by Measuring Phase Difference on Motion Platform
 [PDF]


Journal of Antennas (JA) , 2013, DOI: 10.12677/JA.2013.22003
Abstract:

提出了一种利用机载短基线阵列,以及通过多通道相移测量获得时差变化率的新方法。由相差与时差定位方程即可解出基于相差检测的时差表示式,通过微分,并利用相移与频移间的函数关系即可得到仅基于相差检测的时差变化率。另一方面,如对测向公式进行微分运算,则又可得到仅基于频差检测的时差变化率。模拟计算验证了所导出的时差变化率测算公式都是正确性的。初步的误差分析说明,由于分母上具有量级很大的光速,故基于相差或频差的时差变化率的检测应具有较高的测量精度。新方法将能用于解决在机载平台上时差变化率难以实时检测的问题。 

A new method for detection of time difference rate using short baseline array on airborne platform is presented by measuring the phase shift in multichannel way. The time difference expression based on phase difference measurement can be solved according to phase difference and time difference location equation. Further, the time difference rate based on phase difference measurement can be derived by differential and making use of the functional relationship between phase shift and Doppler shift. On the other hand, the time difference rate based on frequency difference measurement can be obtained if we do the differential analyzer for direction finding formula. The analog calculation validates that derived formula of time difference rate are all correct. The elementary error analysis shows that the measurement accuracy of time difference rate based on phase difference or frequency difference is higher for having the light velocity whose order of magnitude is enormous in denominator of formula. The major contribution in this paper is that the time difference rate on airborne platform can be in real time detected by phase interferometry with short-baseline array.

一种基于相频函数关系的双基时差定位方法
A Double Station Time Difference Location Method Based on Function Relationship between Phase Shift and Doppler Shift
 [PDF]


Journal of Aerospace Science and Technology (JAST) , 2013, DOI: 10.12677/JAST.2013.13003
Abstract:
基于相、频、时三者之间的函数关系,提出了一种有助于改善现有多站时差无源定位性能的定位算法。相对于现有的平面三站时差定位方法,这种先通过频移到相差的函数变换,再利用相差和时差间的关系,将原先仅能用于机载的测距公式转化为与探测平台运动状态无关的双基时差定位方法具有更高的测量精度,避免了对高重频信号测量的定位解模糊,同时相距较远的两主基站间的时间基准可以要求不同步,这无疑有利于站址的选择。仿真结果验证了该算法的有效性。
This paper presents a location algorithm which can help to improve existing performance of multistation time difference location based on the function relationship among phase shift, Doppler shift and time difference. New method uses the relationship between phase difference and time difference based on the function transforms from Doppler shift into phase shift. Finally, the ranging formula that only can apply to airborne platform can be translated into the double station time difference location method which is not associated with the motion state of detection platform. As compared to existing three stations time difference location method in two-dimension plane, the double station time difference location method can heighten measurement accuracy and avoid the time difference ambiguity introduced by high PRF signal. At the same time, it also has the characteristics that the time reference between two major base stations can be deranged, and that looking for the building position of base station is more convenient. Simulation result proves the availability of the algorithm.
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