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The civil aircraft’s manufacturing process is complicated because of its complex structure and various parts in need. The stability and high efficiency of the based supply network decides the coordination ability among departments and the development cycle completion date. Now it’s very urgent to study the robustness of the collaborative supply network. This paper optimized and designed the robustness of the civil aircraft supply network, first with the project evaluation and review technique (PERT) we set a supply network model; then optimized the critical path to make the system functions remain constant, and the civil aircraft supply network robustness got optimized

Civil aircraft is a complex product to manufacture, and the collaborative supply network consist of grades suppliers plays an important part in the progress of development. Due to the interferences from every kind of uncertainties to the network, it’s necessary to find out the critical supply path which decides the completion date for the network going well. This paper first sets the supply network model based on the hierarchical structure of civil aircraft, and then uses Dijkstra and ant colony optimization (ACO) searching for the critical path respectively, in the last the two methods are compared in order to prove performance and superiority.

the paper analyzes reason for the higher uncertainty in the planeness measurement of wood-working machine tools by leveling ruler with adjustable gauge block; proposes a new design idea of new adjustable gauge block and its measuring performance and calibration requirements; and analyzes its uncertainty of measurement.

Through woodworking four-side planer vibration test, this article studiesits dynamic characteristics and dynamic response to identify the vibration magnitudes law of each feed roll shafts of the four-side feed beam; then finds the natural frequency and damping ratio of the feed beam and lathe bed; obtains the mathematical model of feed roll shaft vibration magnitude changing with the feed rate U under different process thicknesses. The analysis of feeding quantity and the rationality of lathe bed from the perspective of vibration design supplies the designs and operation staff with reference data.

With the rapid development of Internet, Internet addiction has become a social issue of common concern. The different kinds of software have emerged to prevent Internet addiction. This paper analyzes and compares those software. A good prevention software should be good information filtering, to identify different kinds of content, web site, can be used to monitor and control the computer, not conflict with the anti-virus software or firewall, and not introduce other new vulnerabilities, not accounting for more memory and more network resources.

To assess the effects of propofol treatments at different time points on acute lung injury and on the expression of transforming growth factor (TGF)-beta1 and the downstream target of TGF-beta1, Smad 2, in the lung tissues in the endotoxic rats.Seventy-six Wistar rats were randomly assigned to five groups: control group (saline only), endotoxemic group [lipopolysaccharide (LPS) 8 mg kg(-1), i.v.], and three propofol-treated groups. For the propofol-treated groups, propofol (5 mg kg(-1), i.v. bolus) was administered either 1 h before LPS, simultaneously with LPS, and 1 h after LPS, and all were followed by infusion of 10 mg kg(-1) h(-1) of propofol for 5 h after LPS. Lung tissues were sampled to measure myeloperoxidase activity and expression of TGF-beta1 and Smad2 and to assess pulmonary microvascular permeability and histopathological changes.The hemodynamics, arterial blood gases, 5 h survival rate, pulmonary microvascular permeability, and acute lung injury scores were significantly better, and expression of TGF-beta1 and Smad2 and myeloperoxidase activity in lung tissues was significantly lower in the pretreatment and simultaneous treatment groups compared to the endotoxemic group. However, there were no significant differences in all observed variables between the endotoxemic and postreatment groups. Except for TGF-beta1 expression in lung tissues, the other observed variables were also not significantly different between the pretreatment and simultaneous treatment groups.In the endotoxic rat model, pretreatment and simultaneous treatment with propofol provided protection against acute lung injury by inhibiting the TGF-beta1-Smad2 dependent pathway.

PNAS-4, a novel pro-apoptotic gene activated during the early response to DNA damage, can inhibit proliferation via apoptosis when overexpressed in some tumor cells. The objectives of this study were to determine whether PNAS-4 could enhance apoptosis induced by cisplatin besides its induction of apoptosis, and to evaluate the usefulness of combined treatment with mouse PNAS-4 (mPNAS-4) gene therapy and low-dose cisplatin chemotherapy in the inhibition of tumor growth in colon carcinoma (CT26) and Lewis lung carcinoma (LL/2) murine models.In this study, the in vitro growth-inhibitory and pro-apoptotic effects of PNAS-4 and/or cisplatin on CT26, LL/2, and SKOV3 cancer cells were assessed by MTT assay, flow cytometric analysis, DNA fragmentation, and morphological analysis, respectively. The in vivo antitumor activity of combined treatment with mPNAS-4 gene therapy and low-dose cisplatin were evaluated in the inhibition of tumor growth in colon carcinoma (CT26) and Lewis lung carcinoma (LL/2) murine models. Tumor volume and survival time were observed. Induction of apoptosis was also assessed in tumor tissues.In vitro, PNAS-4 inhibited proliferation of colon carcinoma (CT26), Lewis lung carcinoma (LL/2) and human ovarian cancer (SKOV3) cell lines via apoptosis, and significantly enhanced the apoptosis of CT26, LL/2, and SKOV3 cells induced by cisplatin. In vivo systemic administration of expression plasmid encoding mPNAS-4 (pcDNA3.1-mPS) and cisplatin, significantly decreased tumor growth through increased tumor cell apoptosis compared to treatment with mPNAS-4 or cisplatin alone.Our data suggests that the combined treatment with mPNAS-4 plus cisplatin may augment the induction of apoptosis in tumor cells in vitro and in vivo, and that the augmented antitumor activity in vivo may result from the increased induction of apoptosis. The present study may provide a novel way to augment the antitumor efficacy of cytotoxic chemotherapy.

Based on the time series of GPS station coordinate in the intemational Earth reference frame (ITRF), we evaluate annual micro-behavior of strain field in Chinese mainland with the triangle method. The results show that the annual micro-behavior of strain field is divided into two parts by the north-south earthquake belt in the research region. The prevailing direction of compressive principal strain field is nearly consistent in the western region. From west to east, the direction varies from NS to NE. It is in accordance with the direction of the modern compressive principal strain field. This suggests that geologic deformation in western region was mainly caused by that India tectonic plate pushes the research region northward and the Siberia plate pushes it southward relatively. It is an inheritance of new tectonic motion. The prevailing direction of the compressive principal strain field does not exist in the eastern region. The annual biggest shear strain is different greatly in every grid-cell. The values varies from 4.13×10−8 to 7.0×10−10. By and large the annual biggest shear strain in the western region is bigger than that in the eastern region. And so is the variation between any two consecutive biggest annual shear strains in the same grid-cell. The annual surface dilatation show that in most grid-cells of the research region the surface dilatation is in compressibility, and the variation between any two consecutive annual surface dilatation in the same grid-cell is small.

In this paper, observation data in 25 GPS reference stations of China have been analyzed by calculating GPS position coordinate time-series with GIPSY. Result shows there is an obvious trend variation in such time-series. The trend variations of time series along the longitude and latitude coordinate reflect the motion of each position in the global-plate, in which the trend variation in the vertical direction reveals some large-scale construction information or reflects the local movement around the positions. The analysis also shows that such time-series have a variation cycle of nearly 1.02 a, but the reason still remains to be further studied. At the end of this paper, response of the time-series of M S=8.1 Kunlunshan earthquake was analyzed, and the seismogenic process of M S=8.1 Kunlunshan earthquake, according to the time proceeding and the feature of anomaly, was divided into 3 phases—changes in blocks with forces, strain accumulation, quick accumulation and slow release of energy. At the initial stage of seismogenic process of M S=8.1 earthquake and at the imminent earthquake, coseismic process as well as during the post earthquake recovery, anomaly in vertical direction is always in a majority. The anomalous movement in vertical direction at the initial stage resulted in a blocking between faults, while at the middle stage of seismogenic process, the differential movement between blocks are in a majority, which is the major reason causing energy accumulating at the blocking stage of faults.

A least square fitting algorithm for alignment of multi-open-curved segments and point pairs of anatomical features obtained from both portal images and simulation radiographs has been developed for patient position verification in radiation therapy. A coordinate system associated with each curved segment pair is constructed so that the discrepancies of each segment pair can be obtained easily. The algorithm allows users to select not only multiple curve pairs but also individual point pairs on the important anatomic landmarks. The misregistration is measured by the sum of the position deviation of individual point pairs and ordinate discrepancies of all segment pairs from their corresponding coordinate systems. A mathematical minimization method is applied to seek an optimal transformation for matching of all segment and/or point pairs involved. The reliability of the algorithm has been tested with both phantom and clinical images. The test results indicate that the typical errors are less than 1 mm and 1 degrees in translation and rotation, respectively.

The temporal dispersion effect and compensation approach of femtosecond laser scanning by an acousto-optical deflector (AOD) was studied. The group delay dispersion (GDD) of a single AOD at 800nm wavelength is about 9300fs2. Based on the principle of angular dispersion of AOD and the prism, an approach that uses single prism pre-compensating an AOD for the temporal dispersion was designed and demonstrated by experiments. At center frequency (70MHz) of the AOD, a 398fs pulse is compressed to 122fs, the range of pulse width on the entire bandwidth (50MHz—90MHz) is 120fs—180fs. This approach is demonstrated to be effective on compensation of temporal dispersion for AOD scanning femtosecond laser.

With the consideratioin of both defocused and abaxial cases,the analytical expressions for the 3D transfer function of optical low coherence tomography are derived in this paper.The theoretical stud-ies are concerned with the resolution-related factors,which furnish evidences for the designation and optimization of the systems.According to our study,the axis resolution would increase linearly with the spectral bandwidth,while the signal level would decrease linearly.In the case of defocused scan-ning,although longer focus length and narrower beam aperture could result in an absolute decrement of the resolution,they give an even better defocused imaging property in the whole scanning region.The detected waveform and the actual image of the optical coherence tomography are also given.

In the approximation of pertubation,the thermal wave imaging was proved to be linear shift invariant under some conditions.Based on this fact ,the signal formation mechanism of such a system was interpreted when used in nondestructive evaluation of opaque materials.