CT MAX 640应急维修一例

故障现象:按下SCAN SET键,显示错码:ER123XG FAIL 0001 00010000;同时XG PWR CONT板状态灯ABORT,CONT,ROTOR点亮,继电器SAFETY CONTACT吸合,扫描中止。 故障分析与维修:错码表明球管ROTOR在10秒中内未准备好,相应XG上状态灯亮,说明相应信号流程错误,故可追寻其流程而寻找故障所在。(原理图见CT MAX640 SCHEMATICS

Seismic noise attenuation using nonstationary polynomial fitting

We propose a novel method for seismic noise attenuation by applying nonstationary polynomial fitting （NPF）, which can estimate coherent components with amplitude variation along the event. The NPF with time-varying coefficients can adaptively estimate the coherent components. The smoothness of the polynomial coefficients is controlled by shaping regularization. The signal is coherent along the offset axis in a common midpoint （CMP） gather after normal moveout （NMO）. We use NPF to estimate the effective signal and thereby to attenuate the random noise. For radial events-like noise such as ground roll, we first employ a radial trace （RT） transform to transform the data to the time-velocity domain. Then the NPF is used to estimate coherent noise in the RT domain. Finally, the coherent noise is adaptively subtracted from the noisy dataset. The proposed method can effectively estimate coherent noise with amplitude variations along the event and there is no need to propose that noise amplitude is constant. Results of synthetic and field data examples show that, compared with conventional methods such as stationary polynomial fitting and low cut filters, the proposed method can effectively suppress seismic noise and preserve the signals.

Effects of acute aerobic exercise on motor response inhibition:An ERP study using the stop-signal task

Purpose： The purpose of this study was to determine the effects of acute exercise on motor response inhibition using both behavioral and electrophysiological approaches. Methods： The P3 and N1 event-related potential （ERP） components were recorded while performing a stop-signal task in 21 college students following a moderately intense acute exercise bout for 30 min and a sedentary control session that involved reading. Results： Acute exercise induced a shorter stop signal response time （SSRT） as compared to control; however, the go response time （Go RT） remained unchanged. In examining the ERP data, acute exercise increased both P3 amplitude and latency but did not affect the N1 component. Conclusion： Acute exercise has a selective and beneficial effect on cognitive function, specifically affecting the motor response inhibition aspect of executive function. Furthermore, acute exercise predominately impacts later stages of information processing during motor response inhibition, which may lead to an increase in attentional resource allocation and confer the ability to successfully withhold a response to achieve motor response inhibition.

Electromagnetic Torque Estimation of a Three-Phase Induction Motor for Setting the Feedrate of a Milling Machine

In this paper, it presents a project of a fuzzy controller and a neural estimator to control a coordinate table powered by three-phase induction motor, aiming to implement an intelligent milling system. The position/speed control is performed using vector techniques of three-phase induction machines. The estimation of the motor electromagnetic torque is used for setting the feedrate of the table. The speed control is developed using TS （Takagi-Sugeno） fuzzy logic model and electromagnetic torque estimation using neural network type LMS （least mean square） algorithm. The induction motor is powered by a frequency inverter driven by a DSP （digital signal processor）. Control strategies are implemented in DSP. Simulation results are presented for evaluating the performance of the system.

Cellular Response to Irradiation

To explore the nonlinear activities of the cellular signaling system composed of one transcriptional arm and one protein-interaction arm, we use an irradiation-response module to study the dynamics of stochastic interactions. It is shown that the oscillatory behavior could be described in a unified way when the radiation-derived signal and noise are incorporated.

Toll-like receptors,a double-edged sword in immunity to malaria

Toll-like receptors(TLRs) are a central component of innate immune system and play a major role as the initiator of the innate immune responses to defend against bacteria,viruses,parasite and other pathogens.During malaria infection,TLRs signaling pathways are initialed with the recognition of Plasmodium glycosylphosphatidylinositols(GPI) and hemozoin as pathogen-associated molecular patterns(PAMPs).And then,activation of TLRs signaling induces specific biological responses against malaria parasites invasion.However,TLRs are also involved in malaria pathogenesis and enhancement of immune tolerance and evasion for malaria infection.Moreover,malaria parasites regulate selectively TLRs expression on immune cells.Thus,these evidences indicated that TLRs have contrary roles on malaria infection.Understanding the complicated roles of TLRs on malaria infection will contribute us to design more effective anti-malaria drugs or vaccines.

Two-direction nonlocal model for image interpolation

How to sufficiently exploit the self-similarity of natural images for image restoration has attracted extensive interest in the field of image processing in recent years.In fact,the self-similarity implies two-direction similarity structures inherent in images,when a group of similar patches are rearranged to form a matrix,there exists similarity between both columns and rows of this matrix.In this paper,we propose a two-direction nonlocal model (TDNL) to symmetrically exploit the two-direction similarity structures in images,the model directly takes the similar patches as local adaptive dictionary to represent each patch in the image and constrain the representation coefficients by Tikhonov regularization.TDNL can achieve the best results so far and obtain significant gains over the existing methods,in terms of both peak signal to noise ratio (PSNR) measure and the visual quality when it is applied to the problem of image interpolation.