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Air-exposed silver surface is investigated in a multifunctional ultrahigh vacuum system to find out the quantitative relation between thermal treatment and the electron-induced secondary electron yield (SEY). Silver-coated samples are heated in the range of about 100–320 °C for up to 120 min, and thermal desorption is characterized. The SEY is then measured in situ as a function of primary electron energy. The maximum SEY is found to decrease almost linearly with the increase in the logarithmic thermal desorption amount determined by the heating time in a designed process. Reduction of SEY also shows a linear relationship with sample temperature in the observed range. Residual gas analysis demonstrates that the SEY reduction depends strongly on the rapid water desorption. In combination with the results of Ar-ion cleaning and Monte Carlo simulation, this work provides a new insight into the SEY variation due to surface desorption of different gases.

The novel ultralight material Mg-10.1Li-3.1Al-2.9Zn alloy (Mg-Li alloy) of which the density is about half that of pure magnesium has a wide application prospect in various industrial fields, while its weldability is rarely investigated. This study explored the fiber laser welding of 5 mm-thick Mg-Li alloy in butt-welding configuration through a L16 (43) orthogonal experiment design. The microstructures of the base metal and the joint obtained under the optimum condition were observed. The results showed that the strengthening precipitates in base metal were τ1 (Li8MgSi6), τ3 (Li2MgSi) and MgLiAl2 with a size in several microns and nano-sized AlLi, while that in fusion zone were nano-sized Li0~0.9Mg2Si and MgLiAl2. The tensile strength of the welded joint was equivalent to that of BM while the impact toughness and plasticity slightly reduced. It was found that the corrosion resistance of fusion zone with the single-phase matrix (β-Li) was about 3.2 times that of BM with the dual-phase matrix (α-Mg + β-Li). The results provided guiding significance for the popularization and application of the novel ultralight material Mg-Li alloy in industry.

With the improvement of the reliability of NC machine tools, it is becoming more and more difficult to obtain a large number of fault data. To deal with this problem, the improved Bootstrap sampling method is proposed. The failure data, which is gained by using seven a type of NC machine tools to monitor failure data for half year, is used respectively for the improved Bootstrap sampling method and the classic series research method. The results have been analyzed and calculated, and show that the Bootstrap sampling method’s relative error is obviously lower than the classic series research method’s. The improved Bootstrap sampling method is proved to be feasible in reliability modeling.

Background and Aim Ganglionated plexi (GP) ablation has been become an important strategy for treating atrial fibrillation (AF). We hypothesize that active GP is a predictor of AF recurrence after minimally invasive surgical AF ablation. Methods Eighty-nine patients with symptomatic lone AF undergoing minimally invasive surgical pulmonary vein isolation combined with GP testing and ablations were followed for a median of 50 months. Success was defined as freedom from any atrial tachyarrhythmia lasting >30 seconds duration. Results The single-procedure success rate is 56.3% for paroxysmal AF, 27.3% for persistent AF, and 25% for long-term persistent AF. A mean of 4.1 active GPs were identified in each patient. There were more active GP on the right side than on the left side (2.8 ± 2.2 vs. 1.4 ± 1.2, p 24 months, early recurrence of AF, and left atrial diameter also predicted long-term recurrences of AF. Conclusions The number of active GP is a predictor of AF recurrence after minimally invasive surgical AF ablation. Patients with more active GP were associated with markedly higher single-procedure success rates. doi: 10.1111/jocs.12299 (J Card Surg 2014;29:279–285)

The bioactive molecules of garlic are classified according to their enzymatic activities as either alliinase activators or alliinase inactivators. The alliinase activation reaction system is mainly composed of sulfur-containing compounds, whereas the alliinase inactivation system is mainly composed of amino acid-based materials. The purpose of this study was to develop an effective way to digitally express features of complex active compounds of garlic as a basis for quality control. HPLC was used to develop the fingerprints of plants from different Allium species and different geographical regions according to whether the compounds were sulfur containing or based on amino acids. Using the Shannon equation, I values of sulfur-containing compounds from garlic ranged from 3.55 to 3.94, whereas I values of sulfur-containing compounds from other Allium plants, onions, leek, and Welsh onion, ranged from 3.38 to 3.53. The I values of amino acid-based compounds from garlic ranged from 3.67 to 3.91, whereas I val...

Background Peripheral blood-based gene expression patterns have been investigated as biomarkers to monitor the immune system and rule out rejection after heart transplantation. Recent advances in the high-throughput deep sequencing (HTS) technologies provide new leads in transcriptome analysis. Methods By performing Solexa/Illumina's digital gene expression (DGE) profiling, we analyzed gene expression profiles of PBMCs from 6 quiescent (grade 0) and 6 rejection (grade 2R&3R) heart transplant recipients at more than 6months after transplantation. Subsequently, quantitative real-time polymerase chain reaction (qRT-PCR) was carried out in an independent validation cohort of 47 individuals from three rejection groups (ISHLT, grade 0,1R, 2R&3R). Results Through DGE sequencing and qPCR validation, 10 genes were identified as informative genes for detection of cardiac transplant rejection. A further clustering analysis showed that the 10 genes were not only effective for distinguishing patients with acute cardiac allograft rejection, but also informative for discriminating patients with renal allograft rejection based on both blood and biopsy samples. Moreover, PPI network analysis revealed that the 10 genes were connected to each other within a short interaction distance. Conclusions We proposed a 10-gene signature for heart transplant patients at high-risk of developing severe rejection, which was found to be effective as well in other organ transplant. Moreover, we supposed that these genes function systematically as biomarkers in long-time allograft rejection. Further validation in broad transplant population would be required before the non-invasive biomarkers can be generally utilized to predict the risk of transplant rejection.

This paper uses a mathematical model Virtual Identity Particles, developed by the author, to simulate conjugated motion of complex particles in a fluid. Assimilated the advantages of Eulerian and Lagrangian approaches, this model treats each particle as a variable source term to the fluid and is designed for simulating numerous particles in two-phase flows. The economic formulation in this model is the salient feature. Considering both precision and computational cost, this model maintains an excellent balance between accuracy and efficiency in modeling particulate flows with complex particles. Simulation results demonstrate that this model is viable for investigating complex particulate flows, especially at a moderately high particle number density.

Based on the disadvantages and problems of current detect ways, come up the testing system which using numerical controlled oscillator (NOC), Digital Radio Frequency Memory (DRFM) and digital down-covert to intermediate frequency (IF) processing, introduce the background information, main functions, total structure and design implementation.

Combined effects of sample parameters on polymer charging due to electron irradiation are explored by a novel approach of contour in parallel computing. Transient processes of negative charging of a Kapton film sample irradiated by 10 keV electrons are simulated with a simultaneous scattering-transport model and the existing experimental secondary electron current. As a function of sample thickness and electron mobility, the contour maps are then presented of the steady-state leakage current and surface potential and the total charge accumulated in a charging process. It is found that the leakage current and surface potential behave similarly in the contour form, and the total charge has the local maximum with respect to the sample thickness. Generally, the sample thickness affects the charging process more than the electron mobility, but both have less influence in very strong and weak charging states. Accompanied by discussion of charge dissipation effects, this study offers a comprehensive insight into complicated charging phenomena in electron-based surface microscopy, analysis and measurement.

To compare the safety and usefulness of deep hypothermic circulatory arrest (DHCA) and regional cerebral perfusion (RCP) during pediatric open heart surgery. Between January 1, 2004 and September 30, 2012, 1250 children with congenital cardiac defect underwent corrective operation with the DHCA or RCP technique in the Shanghai Children's Medical Center. Of them, 947 cases underwent the operation with the aid of DHCA (DHCA group), and 303 cases with RCP (RCP group). The mean DHCA time was 30.64±15.81 (7–63) minutes and mean RCP time was 36.18±12.86 (10–82) minutes. The mortality rate was 7.18% (68/947) and 6.60% (20/30) in two groups, respectively. The postoperative incidences of temporary and permanent neurological dysfunction were 6.23% (59/947) in the DHCA group and 2.64% (8/303) in the RCP group (p

Reverse modeling of vehicle suspension control arm is studied. Firstly, the data of vehicle suspension control arm is acquired. Secondly, the scanning point cloud data is processed. Then 3D model of vehicle suspension control arm is reconstructed. Finally, models deviation is analyzed to find out the deficiencies and to improve the accuracy of the model. Reverse modeling based on CATIA can make up the shortage of traditional modeling method and solve the problem of gaining the data of complex curved surface parts. It also can shorten the innovation and improvement cycle of the vehicle suspension control arm and reduce the production cost and enhance enterprise competitiveness.

To assess the activity and safety of postoperative adjuvant immunotherapy with transfusion of cytokine-induced killer (CIK) cells combined with chemotherapy in patients with colorectal cancer.We retrospectively studied 96 consecutive patients with colorectal cancer who were treated with resection between January 2010 and December 2012 as well as adjuvant chemotherapy. Twenty-one of these patients accepted at least 1 cycle of CIK cell transfusion for immunotherapy (CIK group). Disease free survival (DFS), immune cells and treatment related side effects were assessed. The patients were followed up until May 2013.By the end of follow-up, 10 patients (10.42 %) had died. Eighteen patients (18.75 %) had withdrawn. All the patients in the CIK group are still alive, and only 1 patient had withdrawn. Patients in the CIK group had significantly longer DFS than those in the control group [HR = 0.28, 95 % CI (0.09, 0.91), p = 0.034]. The 2-year DFS rates of patients in the CIK group and the control group were 59.65 ± 24.80 % and 29.35 ± 6.39 %, respectively. The CD4(+)/CD8(+) ratios were significantly lower during the period of chemotherapy than those before chemotherapy (p = 0.0038), while the ratios were significantly higher during the period of CIK cell transfusion than those before CIK therapy (p = 0.0484). There were no immediate adverse reactions to the CIK cell transfusions.Adjuvant transfusion of CIK cells prolongs DFS in patients with colorectal cancer.

In order to analyze the mechanism of backfill and surrounding rock of open stope during subsequent backfill mining, take M1 ore body mining in a mine as engineering background, and simulate the mechanism of surrounding rock and backfill by using FLAC3D numerical software. Results show that the backfill can effectively alleviate or transfer the stress concentration state of the room floor and pillar, apparently restrain the displacement of the cavity plate and pillar, and improve the plasticity distribution range in a limited degree.

With the development of automobile industry, more and more people need automotive information. Meanwhile, there’s a great deal of network information which makes people gather information hard. To make people acquire the automotive information more efficiently, an Automotive News Push System is desperately needed. A distributed focused crawler is proposed for the system to assure that the information is accurate and timely. In this paper, distributed system framework and webpage classification are analyzed. Experimental results show that the frameworkare effective, the accuracy and efficiency of crawling are both improved.

Since the features are not prominent and the algorithm is complex during whole reconstruction of section data, a step-by-step optimization reconstruction method is proposed. The order of reconstruction is optimized: line features are reconstructed firstly; Then arc features are reconstructed (constraints are satisfied between the arc and known lines); finally freeform features are reconstructed (constraints are satisfied between the B-spline and known lines/arcs). In this way, the reconstruction accuracy of the line/arc features is ensured in the first. Since freeform features have more freedom, it is convenient to be adjusted to meet the more constraints. Linear boundary constraints are constructed and the algorithm becomes optimization problem of the quadratic objective function under the linear constraints. The examples show that the reconstruction accuracy is improved greatly under satisfying constraints; the expected goal is achieved in real application.

Chronic inflammation plays an important role in nasopharyngeal carcinoma (NPC) development and progression. Aim of this study is to determine whether inflammation-related parameters predict distant metastasis in NPC patients.335 newly diagnosed non-metastatic NPC patients were recruited. The values of the C-reactive protein (CRP), lactate dehydrogenase, albumin, globulin, white blood cell and neutrophil at baseline were measured.Among the above six parameters, only CRP was independently associated with distant metastasis-free survival (DMFS). CRP concentration of advanced T-/TNM-classification patients was higher than those with early classification (P = 0.001). Higher-CRP (CRP ⩾ 2.46 mg/L) predicted shorter overall survival, disease-free survival and DMFS than lower-CRP (CRP2.46 mg/L). In a multivariable model, higher-CRP and advanced N-classification were independent predictors of distant metastasis. On the basis of these two parameters, a prognostic NC-model was developed as following: (1) low-risk (early N-classification and lower-CRP); (2) intermediate-risk (advanced N-classification or higher-CRP) and (3) the high-risk distant metastasis (advanced N-classification and higher-CRP). When compared with the low-risk group, the hazard ratios (HRs) for distant metastasis and death for the intermediate-/high-risk patients were 3.6/16.1 and 2.26/7.61, respectively (both P0.001).We developed a new prognostic model based on CRP and N-classification for predicting distant metastasis and death of NPC patients, which may facilitate patient counselling and individualised treatment.

To improve the surface properties of magnesium alloys, a study was conducted on Cu-Zr-Al composite coatings on AZ91HP magnesium alloy by laser cladding. The influence of laser scanning speed on the microstructures and properties of the coatings was discussed. The coatings consist of amorphous phase, Cu8Zr3, and Cu10Zr7. With the increase of laser scanning speed, the amorphous phase content of the coatings increases and reaches 60.56wt% with the laser scanning speed of 2.0 m/min. Because of the influence of laser scanning speed on the amorphous and crystal phases, the coatings show the maximum elastic modulus, hardness, and wear resistance at the laser scanning speed of 1.0 m/min. At the laser scanning speed of 2.0 m/min, the coatings have the best corrosion resistance.

The female sex is traditionally considered a favorable prognostic factor for nasopharyngeal carcinoma (NPC). However, no particular study has reported this phenomenon. To explore the prognostic impact of gender on patients with NPC after definitive radiotherapy, we reviewed the clinical data of 2063 consecutive patients treated between 1st January 2000 and 31st December 2003 in the Sun Yat-sen University Cancer Center. The median follow-up for the whole series was 81 months. The female and male patients with early stage disease comprised 49.4% and 28.1% of the patient population, respectively. Both the 5-year overall survival (OS) and disease-specific survival (DSS) rates of female patients were significantly higher than those of male patients (OS: 79% vs. 69%, P < 0.001; DSS: 81% vs. 70%, P < 0.001). For patients with locoregionally advanced NPC, the 5-year OS and DSS rates of female vs. male patients were 74% vs. 63% (P < 0.001) and 76% vs. 64%, respectively (P < 0.001). A multivariate analysis showed that gender, age, and TNM stage were independent prognostic factors for the 5-year OS and DSS of NPC patients. The favorable prognosis of female patients is not only attributed to the early diagnosis and treatment but might also be attributed to some intrinsic factors of female patients.

To investigate the protective effect of hypothermia (HT) on brain injury in moderate traumatic brain injury (TBI) rat models and the potential mechanisms, especially the involvement of RIPK1 in apoptosis and necroptosis.Adult Sprague-Dawley rats were randomized to four groups: sham+normothermia (sham+NT), sham+hypothermia (sham+HT), moderate TBI+normothermia (TBI+NT) and moderate TBI+hypothermia (TBI+HT). The sham+HT and TBI+HT groups were submitted to 32°C for 6 hours. The regional cerebral blood flow (rCBF) was assessed 24 hours after TBI; 24 and 48 hours after TBI, the modified neurological severity score (mNSS) was assessed. Immediately after behavioural tests, rats were sacrificed to harvest the brain tissues.mNSS scores were lower in the TBI+HT group compared with the TBI+NT group (p0.01) and cerebral blood flow was better (p0.01). HE staining of the cortex and ipsilateral hippocampus showed pyknotic and irregularly shaped neurons in TBI+NT rats, which were less frequent in TBI+HT rats. The TBI+NT and TBI+HT groups showed higher TNF-α, TRAIL, FasL, FADD, caspase-3, caspase-8, PARP-1, RIPK-1 and RIPK-3 levels than the sham+NT group (all p0.05), but the levels of these proteins were all lower in the TBI+HT group compared with the TBI+NT group (all p0.01).HT treatment significantly reduced RIPK-1 upregulation, which may inhibit necroptosis and apoptosis pathways after moderate TBI.

Bile duct hamartoma (BDH) is a rare liver disease with a rising incidence in recent years. A retrospective study on BDH patients between June 2007 and December 2015 was conducted. All the medical records, including clinical, imaging and pathological characteristics, were retrieved. Follow-up data were obtained by telephone communication. The majority of the patients had no symptoms and the laboratory tests were normal. The appearance on ultrasound examination was variable. The lesion exhibited low density on plain computed tomography and no enhancement in 4 cases, and inhomogeneous enhancement in 1 case. Magnetic resonance imaging examination revealed hypointensity on T1-weighted imaging (WI), hyperintensity on T2WI, no enhancement in 1 case, and enhancement in 4 cases. Two patients underwent magnetic resonance cholangiopancreatography due to jaundice and intrahepatic bile duct dilation. The preoperative diagnosis was liver cancer in 4 cases, hepatic hilar biliary obstruction in 1, chronic calculous cholecystitis in 1, suspected hepatic abscess in 1, and benign liver tumor in 2 cases. All the patients underwent surgery. Nest-like cell arrangements were observed in 2 patients, and in 1 patient the lesion transformed to intrahepatic cholangiocarcinoma, resulting in the patient's death 25 months after surgery. Thus, BDH may transform into a life-threatening cholangiocarcinoma and it should be surgically removed. Furthermore, the mechanism underlying carcinogenesis in BDH requires further investigation.

BackgroundThis study assessed the role of surgical ablation for atrial fibrillation (AF) in decreasing tricuspid regurgitation (TR) and right‐sided heart remodeling in patients after mitral valve procedure.Methods and ResultsBetween 1994 and 2014, 1568 consecutive patients withAFundergoing mitral valve procedure were identified. In 26.0% (n=408), surgical ablation ofAFwas used. Propensity‐score matching (PSM) was performed on the basis of 41 known perioperative risk variables. Survival, reoperation, stroke, and moderate‐to‐severeTR, as well as echocardiography indices in long‐term follow‐up, were compared in 406 matched patient pairs (ablated and nonablated groups). The nonablated group showed significantly higher risks of death (hazard ratio [HR], 1.644; 95%CI, 1.081–2.501;P=0.020), reoperation (HR, 2.644; 95%CI, 1.299–5.466;P=0.008), and moderate‐to‐severeTR(HR, 1.436; 95%CI, 1.059–1.948;P=0.020), associated with a significantly deteriorated cardiac function, progression ofTR, and right‐sided heart remodeling after 5‐year follow‐up. In a subgroup comparison of ablated patients with sinus rhythm versusAFrecurrence, aPSManalysis was performed at the 5‐year follow‐up. The recurrent group showed significantly higher risks of moderate‐to‐severeTR(HR, 2.427; 95%CI, 1.261–4.671;P=0.008).AFrecurrence was associated with progressiveTRand significant deterioration in right‐sided heart remodeling.ConclusionsIn a retrospectivePSManalysis, mitral valve disease withAFwas associated withTRprogression as well as right‐sided heart remodeling, which are alleviated by surgical ablation.

The environmental magnetism method has been widely applied to identify soil heavy metal pollution, which is characterized by simplicity, efficiency, non-destructivity and sensitivity. The present study used magnetic susceptibility to assess the accumulation of heavy metals in soils of the Caofeidian industrial zone which is a typical reclamation area in northern China. The study area was divided into three sub-zones based on the function, including industrial zone, living zone, natural tidal flat and wetland. A total of 35 topsoil samples (0-10 cm) and 3 soil profiles were collected from the three sub-zones. Magnetic susceptibility (X(lf)), iron oxide (Fe2O3) contents and heavy metals contents (Cr, Ni, Cu, Zn, As, Pb, Mn and V) of the samples were analyzed. The results showed that X(lf) values and heavy metals contents exhibited higher spatial variability in the top soil of the industrial zone, indicating the severe impacts of industrial activities. In the soil profiles of the industrial and living zones, all heavy metals were enriched to different degrees in the upper layer (0-20 cm). However, there was no significant change of heavy metal contents in the soil profiles of tidal flat which was far from the industrial area. The X(lf) value was significantly (P0.01) positively correlated with the contents of Fe2O3, Ni, Cu, As and V in the industrial top soil. This indicated that X(lf) could be used as an indicator for heavy metal accumulation in the industrial zone. However, the X(lf) value was not suitable to be an indicator to show the heavy metal accumulation in the soils of living zone and natural tidal flat. This might be associated with the different sources of magnetic materials among the different sub-zones and the special characteristics of the soils in the tidal flat and wetland.

The style of clothing is complex and changeable, there are many kinds of clothing styles, different styles have different emotional expression, but the current description of clothing emotions is mostly qualitative characterization, and the words to express which have no systemic analysis until now. To establish the clothing semantic emotions space is the important prerequisite for computer recognition of clothing images from emotion made and quantitative evaluation. In the study, the clothing emotions of men's T-shirt are investigated from the choice of description words, voting on the web, initially selection, correlation analysis, and factor analysis, etc. A 3-D space is got for the emotional factors finally, so each image will possess a corresponded 3-D coordinates in the space, which can make it possible to define emotion similarity between images in the factor space, as well as to evaluate and index images of men's T-shirt from the point of clothing emotion in the future. It is the basis to achieve machine evaluation, semantic identification and retrieval of image emotion for men's T-shirt in the next work. The method can also be extended to other type of clothing.

To investigate the effects of β-carboxyethyl germanium sequioxide (Ge-132) and germanium dioxide (GeO

To investigate whether phenotypic modulation of bladder smooth muscle occurs in diabetic rats.Thirty-two male SD rats were randomly assigned into diabetic group and control group. Diabetic rat models were established by a single intraperitoneal injection of streptozotocin (60 mg/kg). Nine weeks later, the bladder tissues of the rats were examined for structural changes using HE and Masson's trichrome staining , and the expressions of myocardin, α-SMA, and SMMHC in bladder smooth muscles were detected with RT-PCR and Western blotting.Compared with the control group, the diabetic rats showed obvious polydipsia and polyuria with significantly increased collagenous fibers and lowered expressions of myocardin, α-SMA, and SMMHC in the bladder tissue (P0.05).s In rats at 9 weeks after diabetic model establishment, phenotypic transition of the bladder smooth muscles occurs to cause bladder contractile dysfunction, which may play an important role in the pathology of diabetic bladder dysfunction.

The resonance Raman spectroscopy in conjunction with the density functional theory calculations were used to study the excited state structural dynamics of 2-mercapto-1-methylimidazole (MMI). The experimental UV absorption bands were assigned according to the time-dependent density functional calculations. The vibrational assignments were done for the A-band resonance Raman spectra of MMI in water and acetonitrile on the basis of the Fourier transform infrared (FT-IR) and FT-Raman measurements in solid, in water and in acetonitrile and the corresponding B3LYP/6-311+G(d, p) computations. The dynamic structures of MMI were obtained by analysis of the resonance Raman intensity pattern and normal mode analysis. The differences in the dynamic structures of MMI and thiourea were revealed and explained. The structural dynamic of MMI was found to be similar to that of 2-thiopyrimidone in terms of major reaction coordinates and thus favored the intra-molecular proton transfer reaction. Copyright © 2012 John Wiley & Sons, Ltd.

This paper examined the mechanical property of rubber mortars with different amount of rubber granules addition and the influence of fly ash, slag and silica fume. The increase of rubber granules results in the decrease in compressive and flexural strength of rubber mortar, but increases the ratio of flexural to compressive strength. The fly ash, slag and silica fume are useful for improving the mechanical property of mortar. The examined contact angle of water against rubber is 99.5°, which suggests the rubber surface is hydrophobic, and the hydrophobic surface interprets the weak interface between rubber and cement matrix.

Slicing of silicon, quartz crystal and other hard brittle materials mainly use dissociated abrasive multi-wire saw slicing technology, which exists some shortcomings, such as severe environmental pollution, lower cutting efficiency, etc. So it is bound to be replaced by fixed abrasive diamond wire saw in the future. At present, generally, the manufacturing technology of fixed diamond wire saw includes electroplating method and resin bonded method. Compared with electroplating diamond wire saw, the resin bonded diamond wire saw has obvious advantages, such as simpler production technique, lower cost, higher cutting efficiency, less environmental pollution, etc. In this paper, the polyurethane was chosen as matrix resin of resin bonded, and phenolic resin was chosen as curing agent, the preparation technology of thermosetting resin bonded diamond wire saw, is researched in this paper. Firstly, the effects of various compositions on resin bonded, are researched, then the optimal fomula and the manufacturing technology are determined

In this paper, firstly we utilize the elastic model, which provides the simplest representation of material behavior in civil engineering. This model is valid for homogeneous, isotropic, continuous materials that exhibit linear stress-strain behavior with no hysteresis on unloading. The elastic models include both isotropic and anisotropic elastic models. Then the Mohr-Coulomb model is used which can represent shear failure in soils and rocks in civil engineering and geotechnical engineering. After that, the strain- softening model is founded, which allows representation of nonlinear material softening and hardening behavior based on prescribed variations of the Mohr-Coulomb model properties (cohesion, friction, dilation, tensile strength) as functions of the deviatoric plastic strain. Finally, a case study is done for the stratified rock mass, the elastic modulus of the rock sample for different surrounding compressive are obtained, to exhibit the anisotropy characteristic of this type of rock material

Slope stability analysis is an important content in geotechnical engineering designing. And the safety factor is still the main index to evaluate the safety status of the whole slope, but the stability of each element of rock mass can not be reflected by the whole safety factor. Some scholars introduce the concept of point safety factor (PSF) to evaluate the stability of each element in rock-soil mass. However, the present work about PSF is remaining in the field of linear model, instead of nonlinear model. But in real situation, the nonlinear failure criterions are more adaptable used to describe the characteristic of rock mass, such as nonlinear failure characteristic of rock strength, structural characteristic and the effect of the stress to the strength of rock mass. So in this paper, the PSF based on the Hoek-Brown nonlinear mechanics model is founded, followed by calculation PSF for one rock mass element stability.

Recently, an algorithm, namely recursive reduced least squares support vector regression (RR-LSSVR), was proposed to reduce the number of support vectors, which demonstrates better sparseness compared with other algorithms. However, it does not consider the effects between the previously selected support vectors and the will-selected ones during the selection process. Actually, they are not independent. Hence, in this paper, an improved scheme, named as IRR-LSSVR, is proposed to update the support weights immediately when a new sample is selected as support vector. As a result, the training sample leading to the largest reduction in the target function is chosen to construct the approximation subset. To show the efficacy and feasibility of our proposed IRR-LSSVR, a lot of experiments are done, which are all favorable for our viewpoints. That is, the IRR-LSSVR needs less number of support vectors to reach the almost same generalization performance as RR-LSSVR, which is beneficial to reducing the testing time and favorable for the realtime.

A new research method that can estimate the demand of EV in China on the basis of vehicular emission inventory and carbon reduction restriction is put forward. By using MOBILE model and software, China vehicular emissions inventory is created. Then, the demand bill of EV is worked out, and replacement scale and proportion of EV are calculated too. In the conclusion part, quantitative data is given, offering theoretical support for the governments’ strategic policy-making in developing EV.

The A-band resonance Raman spectra of thiourea were obtained in water and acetonitrile solution. B3LYP/6-311++G(3df,3pd) and RCIS/6-311++G(3df,3pd) calculations were done to elucidate the ultraviolet electronic transitions, the distorted geometry structure and the saddle point of thiourea in 21A excited state, respectively. The resonance Raman spectra were assigned. The absorption spectrum and resonance Raman intensities were modeled using Heller's time-dependent wavepacket approach to resonance Raman scattering. The results indicate that largest change in the displacement takes place with the C=S stretch mode ν6 (|Δ|=0.95) and noticeable changes appear in the H5N3H6+H8N4H7 wag ν5 (|Δ|=0.19), NCN symmetric stretch+C=S stretch+N3H6+H8N4 wag ν4 (|Δ|=0.18), while the moderate intensities of 2ν15 and 4ν15 are mostly due to the large excited state frequency changes of ν15, but not due to its significant change in the normal mode displacement. The mechanism of the appearance of even overtones of the S=CN2 out of plane deformation is explored. The results indicate that a Franck-Condon region saddle point is the driving force for the quadric phonon mechanism within the standard A-term of resonance Raman scattering, which leads to the pyramidalization of the carbon center and the geometry distortion of thiourea molecule in 21A excited state.

In this study, based on a comprehensive numerical simulation of self-consistent charging, we investigate the formation, evolution and influencing factors of space charge distributions for a grounded insulating thin film of SiO(2) negatively charged by a keV non-penetrating focused electron beam. The simulated space charge presents first positive distributions and then negative ones along both the radial and depth directions because of the difference between electron and hole transports. The variations in distribution occur within a range of the minimum potential acting as a potential barrier for carrier transport. The negative space charge is distributed more widely and deeply, though its peak value in density is usually lower than that of the positive one. Electrons trapped outside the minimum potential range dominate the strength of negative charging. With the increase in potential barrier and the occurrence of leakage current, the space charge eventually reaches equilibrium and exhibits an approximately one-dimensional axial distribution outside the minimum potential range. Distribution features of the space charge density in the equilibrium state correlate with the film and beam parameters via transients of the leakage current. These results and analyses provide new insights into the negative charging effects involved in various electron-beam-based surface microscopic methods, analyses and fabrication techniques.

In this paper, two kinds of rubber surface modifying methods were studied. One was bis[3-(triethoxysilyl) propyl] tetrasulfide (Si-69) silicon alkane coupling agent and the other was crylic acid coupling agent. The mechanical properties of cement concrete with modified rubber crumb and with non-modified rubber crumb were tested respectively. The results show that as the rubber crumb addition rises, the toughness of concrete with non-modified rubber crumb increases while the compressive strength decreases, and both thoughness and compressive strength of cement concrete with modified rubber crumb increase. The chloride impermeability of the rubber concrete are much better than that of the Portland cement concrete. After surface modification the chloride impermeability can be improved more. The thermoanalysis proves that the surface of modified rubber crumb is grafted by polar function groups, so the surface changes from hydrophobic to hydrophilic. The scanning electron microscopy (SEM) analysis confirms that the interface between rubber crumb and cement matrix is improved.

Based on the technology characteristics of CNC system software, the corresponding assurance measures are set for the reliability in design stage, program implementation stage and software testing stage respectively. CNC system software reliability is improved by modularizing program design and structure program design, code review and program readability, using different reliability testing methods. Finally the purpose is accomplished that the whole reliability of CNC system software is improved.

A class of multi-variable decoupling control algorithm for aero-engines is mainly studied In this paper. Firstly, the mechanism of ADRC decoupling control algorithm is elaborated and discussed in detail. Secondly, an ADRC controller for some turbofan engine's nonlinear component-level model is designed to solve two-loop control problem according to the basic principle of ADRC. Compared with ALQR (Augmented Linear Quadratic Regulator) controller in full flight envelope, enough numerical verification tests about ADRC controller have carried out. Finally, simulation results show that the closed-loop system based on the ADRC decoupling controller has better disturbance rejection capability than the ones based on ALQR controller.

Although kernel minimum squared error (KMSE) is computationally simple, i.e., it only needs solving a linear equation set, it suffers from the drawback that in the testing phase the computational efficiency decreases seriously as the training samples increase. The underlying reason is that the solution of Naive KMSE is represented by all the training samples in the feature space. Hence, in this paper, a method of selecting significant nodes for KMSE is proposed. During each calculation round, the presented algorithm prunes the training sample making least contribution to the objective function, hence called as PLOC-KMSE. To accelerate the training procedure, a batch of so-called nonsignificant nodes is pruned instead of one by one in PLOC-KMSE, and this speedup algorithm is named MPLOC-KMSE for short. To show the efficacy and feasibility of the proposed PLOC-KMSE and MPLOC-KMSE, the experiments on benchmark data sets and real-world instances are reported. The experimental results demonstrate that PLOC-KMSE and MPLOC-KMSE require the fewest significant nodes compared with other algorithms. That is to say, their computational efficiency in the testing phase is best, thus suitable for environments having a strict demand of computational efficiency. In addition, from the performed experiments, it is easily known that the proposed MPLOC-KMSE accelerates the training procedure without sacrificing the computational efficiency of testing phase to reach the almost same generalization performance. Finally, although PLOC and MPLOC are proposed in regression domain, they can be easily extended to classification problem and other algorithms such as kernel ridge regression.

This paper proposed a novel mechanism for an unmanned electric vehicle with four-wheel independent driving (4WID), independent steering (4WIS), independent suspending and independent braking. This unmanned electric vehicle adopted the technologies of driving by wire, steering by wire and braking by wire. Which improved the maneuverability of the vehicle greatly and made it achieving straight, oblique, lateral movement, zero radius turning and other movement patterns. Detailed implementation mechanism and virtual prototype of the vehicle were given in this paper. The hydraulic circuit schematic diagram and control method of the braking system were given also.

According to the failure of wind turbines in operation, the failure cause and phenomenon of wind turbines is analyzed, combined with the reliability of wind turbine subsystems, measures aiming at cooperation parts and purchased parts are proposed, the reliability of the whole wind turbines is improved in a certain extent. At the same time, condition monitoring system can carry through the early detecting and diagnosing to potential component failure maintain. Besides, automatic lubrication system can realize accurate and timeliness lubrication, also can reduce maintenance workload, preserve correct lubrication and smooth running of all parts.

In this paper, a fast method of selecting features for kernel minimum squared error (KMSE) is proposed to mitigate the computational burden in the case where the size of the training patterns is large. Compared with other existent algorithms of selecting features for KMSE, this iterative KMSE, viz. IKMSE, shows better property of enhancing the computational efficiency without sacrificing the generalization performance. Experimental reports on the benchmark data sets, nonlinear autoregressive model and real problem address the efficacy and feasibility of the proposed IKMSE. In addition, IKMSE can be easily extended to classification fields.

The charging characteristics and microscopic mechanism of space electrons irradiated polymers are the basis for the study and protection of spacecraft polymer charging and discharging characteristics. Monte Carlo method is used to simulate the scattering process of space electrons, and the fast secondary electron model simulates the generation of secondary electrons. The finite difference method is used to solve the charge transport process of charge continuity equation, current density equation and Poisson equation. The capture process realizes the transmission process of space electrons through the equation based on the Poole-French effect. Based on the electronic scattering/transport synchronization model and combined with the geostationary earth orbit electronic spectrum distribution theoretical formula of the French National Aeronautics and Space Research Agency (ONERA) and the ground experimental method of the agency (SIRNE), a scattering model based on the electron spectrum distribution in geosynchronous orbit is established. The numerical simulation of the charging process of space electrons irradiated polymers is carried out. The space charge density, space potential, electric field distribution and the space potential of polymer sample under the irradiation of single- and multi-energy electrons in space environment are obtained. The relationship among charging characteristics, microscopic parameters and surface potential of the sample is clarified. The surface potential characteristics of space electrons irradiated polymer are consistent with the experimental results. The single energy charge potential and strength are higher than those of multi-energy electrons. When the charging reaches a steady state, the electron mobility is smaller (less than 10–11 cm2·V–1·s–1), and the absolute value of the space potential is significantly enhanced with the decrease of the electron mobility. When the composite rate is large (greater than 10–14 cm3·s–1), the absolute value of the spatial potential increases with recombination rate increasing. The study of the charging characteristics of space electrons is not comprehensive because only the mode of single-energy electron irradiation is taken into consideration. The research results are of great scientific significance and practical value for revealing the charging characteristics and microscopic mechanism of space electrons irradiated polymer and improving the research level of spacecraft charge and discharge fault mechanism.

Papillary meningioma is an uncommon meningioma subtype of World Health Organization grade III. It could show some radiologic profiles pointing to malignant behavior, such as a cystic change, a heterogeneous enhancement, and an ill- defined border. However, to date, the radiologic profile described in this article has not been reported in previous literatures, and it is just the characteristic being considered as the major cause for patients’ death. A 16-year-old adolescent boy with a 6-month history of headache was admitted to our department on June 28, 2012. Magnetic resonance imaging showed a giant well-defined mass in the left temporal region, with a severe flow void on T2-weighted image and an abundant stripelike enhancement on T1-weighted contrast-enhanced scan. In view of its middle cranial fossa location (one predilection site for meningioma), meningioma was suspected preoperatively. A regular left frontotemporal craniotomy was performed. Unexpectedly, extreme hemorrhage happened intraoperatively, and it was difficult to stop the bleeding. After identification of no hemorrhage in the operative cavity through intraoperative magnetic resonance imaging, the operation was finished, with an overall blood loss of 15,000 mL. The patient died of brain stem dysfunction the second day after the operation.

The objective of this study was to evaluate the effect of pulsatile flow on cerebral blood flow (CBF) in infants with the use of a mild hypothermic cardiopulmonary bypass (CPB). Thirty infants scheduled for open heart surgery were randomized to the pulsatile group (Group P, n = 15) and nonpulsatile group (Group NP, n = 15). In Group P, pulsatile perfusion was applied during the aortic cross-clamping period, whereas nonpulsatile perfusion was used in Group NP. The systolic peak velocity (Vs), the end of diastolic velocity (Vd), the mean velocity (Vm), and the pulsatility index (PI) and the resistance index (RI) of the middle cerebral artery were measured by a transcranial Doppler (TCD) ultrasound after anesthesia (T1; baseline), at the beginning of CPB (T2), 10 min after aortic cross-clamping (T3), 3 min after declamping (T4), at the cessation of CPB (T5), and at the end of the operation (T6). During T3 and T4, the Vs in Group P was significantly higher than in Group NP. However, there were no statistically significant differences between Vd and Vm. The PI and RI in Group P were also higher than those in Group NP (both P < 0.05). During T5, Vd and Vm were higher in Group P (P < 0.05), whereas there was no difference in Vs. Additionally, PI and RI in Group P were significantly lower than those in Group NP (P < 0.05). However, there was no difference during T6. Pulsatile perfusion may increase CBF and decrease cerebral vascular resistance in the early period after mild hypothermic CPB.

The method of state space model fitting is carried out by using the linear relation of the variable of the differential equations and separating the steady process and instant process to eliminate the steady errors course by instant errors. The improved fitting method is without solving the linear differential equations or using any iterative methods. The coefficient of the state space model can be solve simply using matrix operation under the premise of high accuracy, so it has a higher computational efficiency than former least square method. And this method can also be used with other fitting method. Finally, to illustrate the validity and accuracy of the improved method, a small perturbation state space model of a certain turboshaft engine model has been established by this method, and the simulation result between state space model and nonlinear model was also compared. Also, the state space model could be applied to fault diagnosis and control system design for aeroengines.