小波变换在调制度测量轮廓术中的应用

基于调制度分析的光学垂直测量技术利用投影和成像共轴,可以有效地解决复杂物体和台阶状物体测量时所存在的遮挡、阴影等问题.该方法不需要截断相位计算和相位展开过程,只需解算条纹的调制度分布就能得到被测物体的三维面形,已成为广泛应用的光学三维检测方法.针对基于傅里叶变换方法的垂直扫描测量技术存在的问题,利用小波变换的局部和多分辨率特性,将小波分析技术用于调制度测量轮廓术中,提高了每个扫描位置获取单帧条纹的调制度测量的精度.推导了调制度和小波系数之间的关系,计算机模拟和实验均验证了方法的有效性.

An Enhanced Hadoop Heartbeat Mechanism for MapReduce Task Scheduler Using Dynamic Calibration

MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a heartbeat mechanism for MapReduce Task Scheduler using Dynamic Calibration （HMTS- DC） is proposed to address the unbalanced node computation capacity problem in a het- erogeneous MapReduce environment. HMTS- DC uses two mechanisms to dynamically adapt and balance tasks assigned to each com- pute node： 1） using heartbeat to dynamically estimate the capacity of the compute nodes, and 2） using data locality of replicated data blocks to reduce data transfer between nodes. With the first mechanism, based on the heart- beats received during the early state of the job, the task scheduler can dynamically estimate the computational capacity of each node. Us- ing the second mechanism, unprocessed Tasks local to each compute node are reassigned and reserved to allow nodes with greater capacities to reserve more local tasks than their weaker counterparts. Experimental results show that HMTS-DC performs better than Hadoop and Dynamic Data Placement Strategy （DDP） in a dynamic environment. Furthermore, an en- hanced HMTS-DC （EHMTS-DC） is proposed bv incorporatin historical data. In contrastto the ＂slow start＂ property of HMTS-DC, EHMTS-DC relies on the historical computation capacity of the slave machines. The experimental results show that EHMTS-DC outperforms HMTS-DC in a dynamic environment.

The establishment of 3D visualization modeling for the jointed slope

The 3D visualization model of slop with structural plane can displayed the characters of structural plane in slop directly, and illustrated the spatial combination. It is a modem and critical question in the field of geotechnical engineering. Based on the peculiarity of the reconnaissance and the research of the visualization by formers, systemized the method fit for building 3D visualization model of slop with structural plane. Write the special program with Visual C^-＋ computer language and illustrated it by OpenGL, the program can displayed and captured the random section plane. The program has a satisfied result by proving with the real projects.

Scheduling of Household Power Consumption for Step and Time-of-Use Tariff System

This paper proposes a hybrid optimization to solve the scheduling of household power consumption for Step and Time-of-Use (TOU) tariff system. The target function is the cost of electricity, and the optimization object is total instantaneous power within a billing period. The control variables are starting moments of each household appliance. The optimization procedure is divided into two stages. Firstly, the prerequisite for minimal cost is calculated through mathematical analysis and generalized function theory. Secondly, the solution is obtained by using a heuristic algorithm in which the result of the first stage is considered to reduce the searching space. And an evaluation methodology is deduced to evaluate the optimization. The computer simulation demonstrates that the proposed approach can reduce the cost of electricity evidently in the sense of probability. The approach shows great value for embedded applications.

Bone marrow-sparing intensity-modulated radiotherapy for postoperative treatment of cervical cancer

Objective： The aim of this study was to compare bone marrow-sparing intensity-modulated radiotherapy （IMRT） with IMRT without entering pelvic bone marrow as a planning constraint in the treatment of cervical cancer after hysterectomy. Methods： For a cohort of 10 patients, bone marrow-sparing IMRT and routine IMRT planning were designed. The prescribed dose was 45 Gy/1.8 Gy/25f, 95% of the planning target volume received this dose. Doses were computed with a commercially available treatment planning system （TPS） using convolution/superimposition （CS） algorithm. Plans were compared according to dose-volume histogram （DVH） analysis in terms of planning target volume （PTV） homogeneity and conformity indices （HI and CI） as well as organs at risk （OARs） dose and volume parameters. Results： Bone marrow-sparing IMRT had an vantages over routine IMRT in terms of CI, but inferior to the latter for HI. Compared with routine IMRT, V5, Vl0, V20, V30, V40 of pelvic bone marrow of bone marrow-sparing IMRT reduced by 1.81%, 8.61%, 31.81%, 29.50%, 28.29%, respectively. No statistically significant differences were observed between bone marrow-sparing IMRT and routine IMRT in terms of small bowel, bladder and rectum. Conclusion： For patients with cervical cancer after hysterectomy, bone marrowsparing IMRT reduced the pelvic bone marrow volume irradiated at all dose levels and might be conducive to preventing the occurrence of acute bone marrow toxicity.

THE DEVELOPMENT AND EXPERIMENT OF A COMPUTER-CONTROLLED TRUCK DISPATCHING SYSTEM IN SURFACE MINE

The development and experiment of a computer-controlled truck dispatching system in Surface mine is presented in this paper.It includes the system overall design, the system working mode design, the selection of the best truck travel path, the development of truck fleet programming, the development of database management system, and the development of truck real time dispatching, etc. The successful experiment is carried out in Huolinhe surface mine, and the satisfied results are obtained. Application of this system can improve the system production and the mine management. This system is the first one in our country at present.

Spectral Calculation of the Output Voltage of an Inverter with Bipolar Pulse Width Modulation

Converters with pulse width modulation are used for connections between the direct current （DC） and alternating current （AC） networks, e.g., in uninterrupted power supply systems, AC electromotor drives, for powering induction furnaces, in audio technique. Spectrum of signals sampled by pulse amplitude modulation and output voltage spectrum of the converter with pulse width modulation have similar properties. Spectrum of signals sampled by pulse amplitude modulation contains a harmonic of frequency equal to the frequency of the modulating signal and the harmonics of frequencies equal to the sum of frequency of the modulating signal and multiples of the sampling frequency. The output voltage spectrum of the converter with bipolar pulse width modulation contains harmonic of frequency equal to the frequency of the modulating signal and harmonics of frequencies equal to sum of the frequency of the modulating signal and multiples of the frequency of the carrier signal. It also contains harmonics of frequencies equal to the sum of the multiples of the frequency of the modulating signal and the multiples of the carrier signal. The comparison analysis was carried out for the harmonics of the output voltage of the converter with bipolar pulse width modulation in time domain. The dependency of the amplitudes and frequency spectrum on the wave forms of the carrier signal and modulating signal was shown. Similarity of the output voltage spectrum of the converter and signal spectrum sampled by the pulse width modulation was also shown. Key words： Output voltage converter with bipolar pulse width modulation, spectral analysis, Fourier series, carrier signal, reference signal.

Influence of Adjusting Control Accuracy on Pressure Probe Measurements in Turbo Machines

This paper presents a new design of a probe adjusting device intended to position pressure and temperature probes in a flow field. 5-hole, 3-hole and temperature probes can be moved in radial direction and freely rotated about their axis. The high actuation accuracy of 3.9 ktm in radial direction and 0.09~ in angular position is validated in a 2-stage-turbine test rig which is installed at the Institute of Power Plant Technology, Steam and Gas Turbines, RWTH Aachen University. To meet the challenge to calculate the efficiency of a turbo machine which is mainly influenced by the temperature, all probe adjusting devices are positioned simultaneously and controlled by the MAS （measuring acquisition system） so that the same radial position in each stage is measured at the same time. For this purpose a new program has been developed to synchronize actuation and measurement. The slim design of 60 mm width allows measurement between the stages of turbo machines with small axial distances between vane and blade. In addition a CFD/FEA shows how the design and combination of materials compensate the thermal expansion of the engine during operation. This allows a minimal safety distance of 0.2 mm between rotor and probe to enable measurement as close to the physical boundary as possible. The actuation accuracy is demonstrated with pressure, temperature and angle distribution plots. It is also shown that the resolution of the measuring points, and therefore the actuation distances, has a large impact on the flow field analysis and should be set as high as possible. However the measuring time has to be taken into account.