“缺火”故障诊断

所有的OBD(车载电脑诊断)系统都可以识别发动机的缺火故障,但各个汽车生产厂家提供的技术方式有所不同,因此,如何作出正确诊断就成了维修技术人员感到棘手的问题。本文给出了一些提示与步骤,可以帮助你更快更准确地对缺火故障进行诊断分析。

Defect image segmentation using multilevel thresholding based on firefly algorithm with opposition-learning

To segment defects from the quad flat non-lead QFN package surface a multilevel Otsu thresholding method based on the firefly algorithm with opposition-learning is proposed. First the Otsu thresholding algorithm is expanded to a multilevel Otsu thresholding algorithm. Secondly a firefly algorithm with opposition-learning OFA is proposed.In the OFA opposite fireflies are generated to increase the diversity of the fireflies and improve the global search ability. Thirdly the OFA is applied to searching multilevel thresholds for image segmentation. Finally the proposed method is implemented to segment the QFN images with defects and the results are compared with three methods i.e. the exhaustive search method the multilevel Otsu thresholding method based on particle swarm optimization and the multilevel Otsu thresholding method based on the firefly algorithm. Experimental results show that the proposed method can segment QFN surface defects images more efficiently and at a greater speed than that of the other three methods.

Gauge dependence of chiral condensate and fermion mass by an unquenched model

Based on three-dimensional quantum electrodynamics theory,a set of truncated Dyson-Schwinger（D-S） equations are solved to study photon and fermion propagators with the effect of vacuum polarization.Numerical studies show that condensation and the value of fermion mass depends heavily on how the D-S equations are truncated.By solving a set of coupled D-S equations,it is also found that the fermion propagator shows a clear dependence on the order parameter.The truncated D-S equations under unquenched approximation are used to study the mass-function and chiral condensation of the fermions.The results under the unquenched approximation are clearly different from the ones under quenched approximation.With the increase in the order parameter,the fermion condensation in the unquenched approximation decreases when 0≤ξ5,while it increases when ξ5.However,nothing like this is observed in the quenched approximation,which indicates that there may be flaws in the quenched approximations.

Magnet Design and Engineering Technique Study on a 100MeV Compact H-Cyclotron

A 100MeV compact high intensity H-cyclotron is under design and construction at CIAE which will provide a 75MeV—100MeV,200μA proton beam.The main magnet of this cyclotron adopts an integrally compact structure with a fixed field and four sectors,while the hill gap is constantly changeable.This paper reviews the design features of the magnet,numerical simulation results,the inner defects of the magnet including the carbon content segregation and shrinkage porosity,factors related to mechanical design including the tolerance and deformation.The latest progress will also be reported in this paper.

Photoluminescence and defect evolution of nano-ZnO thin films at low temperature annealing

Nano-ZnO thin films composed of nanoparticles with sizes of 10-16 nm on silicon substrates at low temperature were prepared by sol-gel method.By placing the nano-ZnO thin films at room temperature or annealing at 100°C in air for 10 h intermittently,within a total 70 h annealing time,the evolution of PL spectra of the nano-ZnO thin films were studied in detail.As the annealing time increases,the PL peaks shift from violet to blue and green bands.The PL peaks at violet and blue bands decrease with the annealing time,but the PL peaks at green band are opposite.The PL spectra are related to the defects in the nano-ZnO thin films.The PL peaks positioned at 430 nm are mainly related to defects of zinc interstatials(Zni),oxygen vacancies and(Vo);the ones at 420 nm to oxygen interstitials(Oi),Zinc vacancies(Vzn),Zni ;and the ones at 468 nm to Vzn,Zni,and charged oxygen interstatials(Vo+).The green luminescence is related to Oi,Vo and Zni.The evolutions of PL spectra and the defects are also related to the concentrations of Zn in the thin films,the thicknesses of the films and the annealing time.For the films with 0.5 M and 1.0 M Zn concentrations,after 20 h and 30 h annealing in air at 100°C,respectively,either placing them in air at room temperature or continuing anneal in air at 100°C,the PL spectra are stable.Under the low temperature annealing,Zni decreases with the annealing time,and Oi increases.Sufficient Oi favors to keep the nano-ZnO thin films stable.This result is important to nano-ZnO thin films as electron transport layers in inverted or tandem organic solar cells.

Treatment of 30 Cases of Vertigo due to Qi-blood Deficiency by Pricking Jingbailao (EX-HN 15) with Fire Needle Therapy

Objective: To observe the clinical effect of fire needle therapy on vertigo due to qi-blood deficiency by pricking Jingbailao (EX-HN 15). Methods: Thirty cases with vertigo due to qi-blood deficiency in conformity with the inclusion criteria were treated with fire needle therapy by pricking Jingbailao (EX-HN15), once every day, seven sessions as one course. The clinical effects were assessed after one course of treatment. Results: After one-course treatment, the results showed cure in 3 cases, remarkable effect in 14 cases, effect in 11 cases and failure in 2 cases out of 30 cases. Conclusion: Fire needle therapy by pricking Jingbailao (EX-HN15) can obviously relieve the clinical symptoms in patients with vertigo due to qi-blood deficiency.

Microsurgical repair at early stage for soft tissue defect of limbs wounded by modern firearm

Objective: To explore an early stage repair method for soft tissue defect of limbs of modern firearm wound, and to improve treating result. Methods: Defects of the hind limbs of dogs were repaired with skin, muscle and myocutaneous flaps. Results: Wounds healed within 2 weeks in the experimental group except one that healed in 3 weeks because of infection. Limb function was close to normal. The treatment result was better in the experimental group than the control. Conclusions: Skin, muscle and myocutaneous flaps can cover soft tissue defect at an early stage, prevent and reduce infection, promote the healing and recovery of combined injury, reduce the time of treatment and disability rate.

Effect of complex reinforcing-reducing manipulation on lower limb motion and balance disorder in patients with subacute combined degeneration of the spinal cord

Objective：To observe the effect of complex reinforcing [Shao Shan Huo （Mountain-burning Fire）] and reducing [Tou Tian Liang （Heaven-penetrating Cooling）] manipulations on motion and balance of the lower limbs in patients with subacute combined degeneration of the spinal cord （SCD）. Methods：A total of 100 SCD cases were randomly allocated into an observation group and a control group by their visit sequence, 50 cases in each group. On the basis of Western medical treatment, cases in the observation group were also treated with acupuncture therapy plus complex reinforcing-reducing manipulation; whereas cases in the control group were only treated with the same Western medical treatment as those in the observation group. Before and 2 months after treatment, kinematic parameters including muscle force, muscle tone and range of motion of the hip and knee joints were measured. In addition, balancing parameters including the path length of center of pressure （COP）, peripheral area, COP path length per unit area and rectangular area were also measured before and after treatment. Results：After treatment, there were statistical intra-group differences in COP path length, peripheral area, COP path length per unit area, left-right offset, rectangular area, coefficient of stability and coefficient of weight distribution （P〈0.01）. There were statistical inter-group differences in muscle force, muscle tone and range of motion of hip and knee joints （P〈0.01）. The total effective rate was 83.3% in the observation group, versus 60.0% in the control group, showing a statistical difference （P〈0.05）. Conclusion：Complex reinforcing-reducing manipulations can improve the lower limb motion and balance in SCD patients.

Magnetic Flux Leakage Signal Inversion of Corrosive Flaws Based on Modified Genetic Local Search Algorithm

In this paper,a modified genetic local search algorithm(MGLSA) is proposed.The proposed algorithm is resulted from employing the simulated annealing technique to regulate the variance of the Gaussian mutation of the genetic local search algorithm(GLSA).Then,an MGLSA-based inverse algorithm is proposed for magnetic flux leakage(MFL) signal inversion of corrosive flaws,in which the MGLSA is used to solve the optimization problem in the MFL inverse problem.Experimental results demonstrate that the MGLSA-based inverse algorithm is more robust than GLSA-based inverse algorithm in the presence of noise in the measured MFL signals.