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Temperature variations in the machine tool structural components may lead to relative pose variations between the tool tip and the workpiece. Different thermal layouts may lead to various temperature distributions and generate various thermal deformations. Thermal symmetric design is often used to complete thermal balancing of machine tools. Studies on theoretical methods to guide the layout design of the heat sources (HS) and cooling sources (CS) in machine tools are insufficient. To address this problem, a novel analytical approach for characterising the equivalent cuboid thermal response of machine tool structural components is presented in this paper. The proposed analytical modelling method can realise analytical temperature field modelling with Green's function, calculating the equivalent thermal moment with Reissner's theory, and matching the thermal power-deformation mapping coefficient (TPDMC) using the finite element method (FEM). The explicit and correlative formulation between the thermal power of the HSs and CSs and the guideway thermal deviations is deduced. Furthermore, the layout principles of the CSs are presented according to the maximum efficiency of the thermal moment and the characterisation matching of the TPDMC curves. Afterwards, power matching of the CS is obtained with the aid of the minimum deformation principles of the key positions. Simulated and experimental results illustrated that the proposed method can be used to rapidly and accurately analyse the temperature and thermal deformation responses of the machine tool, as well as to provide a thermal balancing strategy according to specific thermal conditions. The analytical approach proposed in this paper is a general method suitable for the thermal balancing design of machine tools, and it is of great value for improving the thermally induced accuracy stability of machine tools.

CuMgFe layered double hydroxide (CuMgFe-LDH) was successfully synthesized and characterized as an efficient catalyst of persulfate (PS) for the degradation of ethylbenzene. Under the conditions of 0.2gL-1 CuMgFe-LDH and 4.0mmolL-1 persulfate at pH 7.6, the degradation efficiency of 0.08mmolL-1 ethylbenzene was 93.7% with TOC removal efficiency of 65.2% in 24h, and the concentration of Cu leached into the solution was as low as 0.095mgL-1 after the reaction. The reuse of CuMgFe-LDH showed that the catalyst was highly stable after 5 recycles. Electron Spin Resonance (ESR) test and free radical quenching experiment indicated that SO4- and OH radicals were the dominant species accounted for the degradation of ethylbenzene in the CuMgFe-LDH/persulfate system. Catalytic mechanism of the formation of a complex of Cu(II)O3SOOSO32- and the subsequent redox cycle of Cu(II)/Cu(III) accounted for the generation of radicals was proposed.

To overcome the imbalance between spindle heat generation and dissipation caused by existed spindle cooling strategies, this paper develops a power matching based cooling strategy for motorized spindle unit. Firstly, heat generation, conduction and dissipation are considered for the modeling of spindle structural heat exchange. This modeling methodology conveys that an operating motorized spindle unit will have satisfactory thermal behaviors only if the supply dissipation powers from recirculation coolants are dynamically and respectively equal to their corresponding heat generation powers (mainly from spindle bearings and motor). Based on this principle, the power matching between spindle heat generations and dissipations is realized by the real-time power estimations of spindle heat sources and the modified constant supply cooling powers strategy. It can be ultimately verified by experiments that the power matching based dissipation strategy is more advantageous than existed spindle cooling strategies in dissipation of spindle heat generations and decrease of thermal errors.

Objective: To study the clinical characteristics related to metabolic disorders and complications in type 2 diabetes mellitus patients hospitalized in the Qingdao Endocrine and Diabetes Hospital from 2006 to 2012 in Qingdao, China. Patient population and methods: Data from 14,289 (51% males) type 2 diabetes mellitus patients hospitalized between 2006 and 2012 were collected and analysed. Information on patients’ demographic, anthropometric, laboratory and disease histories were extracted from electronic medical records. Results: The mean age of the patients was 60.5 years, with median diabetes duration of 9.0 years. Mean haemoglobin A1c was 8.4%, where Conclusion: Inadequate control of hyperglycaemia, poor metabolic profiles and diabetic complications were common challenges for long-term diabetes management in Chinese patients with type 2 diabetes mellitus.

Nonalcoholic fatty liver disease (NAFLD) is independently associated with cardiovascular disease and chronic kidney disease. Among patients with type 2 diabetes (T2DM), the relationship between NAFLD and diabetic macrovascular and microvascular complications is unclear. The study population consisted of 2504 patients (M/F: 1520/984, mean age 60.8 ± 10.4 years) with T2DM who have been hospitalized between 2007 and 2011. All subjects had data on anthropometric parameters, total cholesterol (TC), low-density lipoprotein cholesterol, HbA1C, creatinine (Scr), tumor necrosis factor- α (TNF-α), and 24h urine albumin exerting rate (24hUAER). Doppler ultrasound examination was used to diagnose fatty liver and to measure carotid artery intima-media thickness (IMT). Carotid artery intimal thickening was diagnosed as IMT≧1mm. Diabetic nephropathy (DN) was diagnosed if 24hUAER≧30mg/24h. NAFLD accounted for 57.4% of all patients. After adjusting for age, gender, disease duration, systolic blood pressure (SBP), waist and other factors, patients with NAFLD had increased carotid artery IMT (1.11 ± 0.25 vs. 0.87 ±0.18 mm, P Disclosure L. Zhang: None. N. Wang: None. J. Wang: None. X. Yin: None. Y. Yang: None. W. Gao: None. Y. Dong: None.

The current study aims to determine the secular trend of prevalence of type 2 diabetes and prediabetes and risk factors for diabetes from 2002 to 2009. We conducted 3 population-based surveys for diabetes in individuals aged 35-74 years in Qingdao in 2002, 2006 and 2009, respectively, with random-sampling approach. The sample size was 1792, 4549 and 4310 in 2002, 2006 and 2009, respectively. We performed a questionnaire-based survey to collect general information. All participants underwent standardized 2-h 75-g oral glucose tolerance tests (OGTTs). The 1999 WHO diagnostic criteria for diabetes and prediabetes was applied. Age-standardized prevalence of diabetes was calculated. Multiple non-conditional logistic regression were applied to analyze the risk factors for diabetes, taking diabetes as the dependent variable. In 2002, the age-standardized prevalence of diabetes was 12.32%, the corresponding prevalence was 16.57% and 18.01%, respectively, in 2006 and 2009. The prevalence of diabetes increased from 2002 to 2009 (p Disclosure L. Zhang: None. W. Gao: None. N. Wang: None. J. Wang: None. X. Yin: None. Y. Zhu: None. Y. Dong: None.

The study aimed to investigate the effect of 7-point or 5-point glucose monitoring on medical costs, glycemic control and the incidence of hypoglycemia in hospitalized patients with type 2 diabetes (T2DM). A total of 4002 patients with T2DM (1490 male and 2512 female cases) with complete medical records were included between 2012 and 2017. The average age was 61.5 years and the mean disease duration 8.68 years. According to the frequency of daily monitoring of blood glucose during hospitalization, patients were divided into 2 subgroups of 5-point group and 7-point group. Patients in 5-point group received fasting blood glucose (FBG), 2h blood glucose (2hBG) after breakfast, 2hBG after lunch, 2hBG after dinner and bedtime blood glucose tests. Patients in 7-point group received additional tests of pre-lunch glucose and pre-dinner blood glucose. Blood glucose monitoring was performed using Johnson & Johnson SureStep blood glucose meter. Comparison of two groups includes duration of in-hospital stay, medical costs, glycemic control and the incidence of hypoglycemia. Patients in 7-point glucose monitoring group had significantly shorter hospital stay (14.4 vs. 16.6 days, P0.05). At discharge, both fasting and 2-h glucose decreased significantly compared with baseline levels in either 5-point or 7-point group. In 7-point group, FPG decreased by 2.41mmol/L and 2hPG by 3.9mmol/L. In the 5-point group, the corresponding figures were 2.07mmol/L and 3.6mmol/L, respectively. The incidence of hypoglycemia were 24.2% in 7-point group and 33.1% in 5-point group (P Disclosure L. Zhang: None. Y. Gu: None. Y. Yang: None. N. Wang: None. W. Gao: None. J. Wang: None. X. Yin: None. Y. Dong: None.

Textual information embedded in the medical image contains rich structured information about the medical condition of a patient. This paper aims at extracting structured textual information from semi-structured medical images. Given the recognized text spans of an image preprocessed by optical character recognition (OCR), due to the spatial discontinuity of texts spans as well as potential errors brought by OCR, the structured information extraction becomes more challenging. In this paper, we propose a domain-specific language, called ODL, which allows users to describe the value and layout of text data contained in the images. Based on the value and spatial constraints described in ODL, the ODL parser associates values found in the image with the data structure in the ODL description, while conforming to the aforementioned constraints. We conduct experiments on a dataset consisting of real medical images, our ODL parser consistently outperforms existing approaches in terms of extraction accuracy, which shows the better tolerance of incorrectly recognized texts, and positional variances between images. This accuracy can be further improved by learning from a few manual corrections.

Geometric errors of machine tools are one of the main contributors for machining inaccuracies. A multi-step error measurement and compensation method is proposed in this paper to investigate the effects of different geometric errors on volumetric errors. The kinematic error chain is built using multi-body system theory (MBS) and homogenous transformation matrices first. Then, the original geometric errors without any compensations are measured and the deviations of tool tip caused by different geometric errors are calculated. Furthermore, various compensation strategies considering diverse geometric errors effects are carried out in the machine tool to validate the predicted volumetric errors. The multi axis calibrator, which can detect six errors of a translational axis in one measurement, is used to measure the variations of 18 errors of translational axes and volumetric diagonal errors of a three axes machine tool. Besides, the squareness errors were measured by a ball-bar. The pragmatic effects of positioning, straightness, angular and squareness errors on volumetric errors are derived from comparisons between various compensation results. Results reveal that linear errors effect the whole volumetric positioning errors while the angular errors mainly effect the volumetric positioning errors of the region far from reference coordinate point.

A high catalytic system using Cu layered double hydrotalcite (Cu(II)-Mg(II)-Fe(III)LDHs) and hydrogen peroxide (H2O2) was developed for the degradation of ethylbenzene. It was identified that the degradation efficiency of ethylbenzene (0.08 mmol L−1) and TOC removal were 96.1% and 39.7% respectively in the presence of 0.1 g L−1 Cu(II)-Mg(II)-Fe(III)LDHs with (Cu2+ + Mg2+)/Fe3+ molar ratio of 5.0 and 0.16 mmol L−1 H2O2 in 6.0 h. Based on ESR and XPS data, hydroxyl radicals (•OH) were the predominant free radical specials generated from the catalytic decomposition of H2O2 for the degradation of ethylbenzene. The redox of Cu(II)/Cu(III) on the layered Cu(II)-Mg(II)-Fe(III)LDHs surface active sites accounted for the formation of •OH radicals and the cycle of Cu(II) in the Cu(II)-Mg(II)-Fe(III)LDHs/H2O2 system were proposed.

Motorized spindle unit is the core component of a precision CNC machine tool. Its thermal errors perform generally serious disturbance onto the accuracy and accuracy stability of precision machining. Traditionally, the effectiveness of the compensation method for spindle thermal errors is restricted by machine freedom degrees. For this problem, this paper presents an active, differentiated, and intelligent control method onto spindle thermal behaviors, to realize comprehensive and accurate suppressions onto spindle thermal errors. Firstly, the mechanism of spindle heat generation/dissipation-structural temperature-thermal deformation error is analyzed. This modeling conveys that the constantly least spindle thermal errors can be realized by differentiated and active controls onto its structural thermal behaviors. Based on this principle, besides, the active control method is developed by a combination of extreme learning machine (ELM) and genetic algorithm (GA). The aim is to realize the general applicability of this active and intelligent control algorithm, for the spindle time-varying thermal behaviors. Consequently, the contrasting experiments clarify that the proposed active and intelligent control method can suppress accurately and synchronously all kinds of spindle thermal errors. It is significantly beneficial for the improvements of the accuracy and accuracy stability of motorized spindle units.

Volumetric accuracy is susceptible to thermal gradient caused by internal heat source (IHS) and external heat source (EHS). A temperature-structure multi-step calculation method is presented to investigate the influences of EHSs on volumetric thermal errors of precision machine tools. The temperature and structure of the machine tool are simulated first, and then, the volumetric thermal errors are calculated using multi-body theory method. Simulations are completed to study the effects of different EHSs on a machine tool, and series of validating experiments are carried out to verify the modeling method. The test results in specific position and working condition revealed that EHSs contribute 53, 21, and 68% of thermal deviations in X, Y, and Z directions individually. It is illustrated that the EHS is an important factor affecting the volumetric accuracy of precision machine tools. The methods provided in this paper are valuable for machine tool designers to evaluate the EHS effects on volumetric thermal errors during designing process; furthermore, some insulating measures are suggested to improve the accuracy and accuracy stability of precision machine tools by reducing the EHS influences.

The incidence of all cancers in China is generally higher in urban areas; however, the mortality risk for affected patients is considerably higher in rural areas. We present a subanalysis investigating the differences in patient and disease characteristics, treatment patterns, and outcomes between rural and urban patients who were diagnosed with breast cancer at West China Hospital between 2005-2009. Baseline patient and disease characteristics were recorded, and patients were followed up for a minimum of 3 years, or until death. For this subanalysis, patients were stratified by their residential status (rural or urban). Of the 2252 patients in the cohort, 76.3% were from urban areas and 22.1% were from rural areas. Significant differences were observed in the prevalence of luminal A and human epidermal growth factor receptor 2-positive breast cancers among rural and urban patients. Estrogen receptor (ER)-positive patients were less likely to receive anti-ER therapy if they were from rural areas compared with urban areas; the use of aromatase inhibitors was also significantly lower for rural patients than urban patients. Univariate, multivariate, and Kaplan-Meier analyses all demonstrated that overall survival and progression-free survival were significantly lower for rural patients than urban patients.

A reduced graphene oxide (rGO) supported magnetite nanoparticle (nFe 3 O 4 ) composite (nFe 3 O 4 /rGO) was synthesized and shown for the first time to be an efficient persulfate activator to generate SO 4 − for trichloroethylene (TCE) degradation. The degradation efficiency of TCE (0.15 mmol L −1 ) was 98.6% within 5 min in the presence of 6.94 g L −1 nFe 3 O 4 /rGO with an optimum mass ratio of 1:4 and persulfate concentration of 3.0 mmol L −1 . By dispersing nFe 3 O 4 on the rGO surface, nanoparticle agglomeration was prevented and the aggregation of the rGO sheets was disrupted. Both the redox effect coupled in nFe 3 O 4 and the electron transfer by functional groups containing oxygen on the surface of rGO enhanced the SO 4 − generation. Given the identified free radical species and the characterization of the nFe 3 O 4 /rGO, a persulfate activation mechanism by nFe 3 O 4 /rGO for the degradation of TCE was interpreted.

This paper presents an efficient algorithmic implementation of the iterative minimization formulation (IMF) for fast local search of transition state on potential energy surface. The IMF is a second order iterative scheme providing a general and rigorous description for the eigenvector-following (min-mode following) methodology. We offer a unified interpretation in numerics via the IMF for existing eigenvector-following methods, such as the gentlest ascent dynamics, the dimer method and many other variants. We then propose our new algorithm based on the IMF. The main feature of our algorithm is that the translation step is replaced by solving an optimization subproblem associated with an auxiliary objective function which is constructed from the min-mode information. We show that using an efficient scheme for the inexact solver and enforcing an adaptive stopping criterion for this subproblem, the overall computational cost will be effectively reduced and a super-linear rate between the accuracy and the computational cost can be achieved. A series of numerical tests demonstrate the significant improvement in the computational efficiency for the new algorithm.

Pipe route design plays a prominent role in ship design. Due to the complex configuration in layout space with numerous pipelines, diverse design constraints, and obstacles, it is a complicated and time-consuming process to obtain the optimal route of ship pipes. In this article, an optimized design method for branch pipe routing is proposed to improve design efficiency and to reduce human errors. By simplifying equipment and ship hull models and dividing workspace into three-dimensional grid cells, the mathematic model of layout space is constructed. Based on the proposed concept of pipe grading method, the optimization model of pipe routing is established. Then an optimization procedure is presented to deal with pipe route planning problem by combining maze algorithm (MA), nondominated sorting genetic algorithm II (NSGA-II), and cooperative coevolutionary nondominated sorting genetic algorithm II (CCNSGA-II). To improve the performance in genetic algorithm procedure, a fixed-length encoding method is presented based on improved maze algorithm and adaptive region strategy. Fuzzy set theory is employed to extract the best compromise pipeline from Pareto optimal solutions. Simulation test of branch pipe and design optimization of a fuel piping system were carried out to illustrate the design optimization procedure in detail and to verify the feasibility and effectiveness of the proposed methodology.

We introduce efficient approaches to construct high order finite difference discretizations for solving partial differential equations, based on a composite grid hierarchy. We introduce a modification of the traditional point clustering algorithm, obtained by adding restrictive parameters that control the minimal patch length and the size of the buffer zone. As a result, a reduction in the number of interfacial cells is observed. Based on a reasonable geometric grid setting, we discuss a general approach for the construction of stencils in a composite grid environment. The straightforward approach leads to an ill-posed problem. In our approach we regularize this problem, and transform it into solving a symmetric system of linear of equations. Finally, a stencil repository has been designed to further reduce computational overhead. The effectiveness of the discretizations is illustrated by numerical experiments on second order elliptic differential equations.

To develop a visual and reliable weld quality assessment method for resistant spot welding, the electrode displacement signal was measured and analyzed. Some statistical features closely related to the weld quality were extracted. The multi-dimensional extracted features from the signal were sketched as Chernoff face which characterizes the welding quality through the different facial expressions. The weld quality was summarized as four levels, namely poor, good, excellent and expulsion, and each level corresponded to one kind of facial expression. By visual judgment, good or bad welds were identified accurately and rapidly even though the weld was made under abnormal welding conditions. In particular, the visual characteristic makes the diagnostic procedure for welding quality easily understood and interpreted.

We discuss the inexact two-grid methods for solving eigenvalue problems, including both partial differential and integral equations. Instead of solving the linear system exactly in both traditional two-grid and accelerated two-grid method, we point out that it is enough to apply an inexact solver to the fine grid problems, which will cut down the computational cost. Different stopping criteria for both methods are developed for keeping the optimality of the resulting solution. Numerical examples are provided to verify our theoretical analyses.

The motion track of belt spindle is important for the radial error of belt spindle. An analytical modeling method for the motion track of belt spindle under the combined effects of bending moment-torque-thermal deformation is proposed in this paper. Three running phases of belt spindle have been analyzed and modeled: the start-up phase with leaping change due to the change in force and bending moment, the accelerating phase with axis deflection, and the constant speed phase with axis regression because of the combined effects of bending moment-torque-thermal deformation. The simulation and test were completed on the belt spindle of SKVM850 machine tool, which illustrates the variation law of the radial error of belt spindle during the whole running phases.

Inverse design is a promising approach in the realm of material science for finding structures with desired property. We developed a new package with novel algorithm for inverse design named as IM2ODE (inverse design of Materials by Multi-Objective Differential Evolution). The target properties of concern include the optical and electronic-structure properties of semiconductors, hardness of crystals, etc. IM2ODE can easily predict the atomic configurations with desired properties for three dimensional structure, interface and cluster, even complex defect in solid. Tests have been run on multiple systems and it has been proved that IM2ODE is highly efficient and reliable, which can be applied widely.

Traditional bath recirculation cooler for precision machine tools always has the uniform and open-loop cooling strategy onto different heat generating parts. This causes redundant generated heat being transferred into the machine structure, and results in unsatisfactory thermal errors of precision machine tools. For the solution of this problem, this paper presents the differentiated multi-loops bath recirculation system. The developed system can accomplish differentiated and close-loop cooling strategies onto machine heat generating parts during its operation. Specially, in order to illustrate the advantages of this system, constant supply cooling powers strategy is presented with its applications onto a certain type of built-in motorized spindle. Consequently, advantages of the proposed strategy based on the differentiated multi-loops bath recirculation system are verified experimentally in the environment within consistent temperature (TR = 20 ± 0.3°C). Compared with room temperature tracing strategy based on the traditional bath recirculation cooler, the constant supply cooling powers strategy is verified to be advantageous in spindle temperature stabilization and thermal errors decrease.\ud

This paper proposes and analyzes an iterative minimization formulation for searching index-1 saddle points of an energy function. We give a general and rigorous description of eigenvector-following...

Branch pipe routing problem can be formulated as finding the Rectilinear Steiner Minimal Trees with Obstacles (RSMTO) (Liu & Wang 2012). For the RSMTO problem, one of the important tasks is to construct a reasonable layout space model.

Fruit, vegetable, seafood, and dairy intake may reduce the risk of type 2 diabetes, but this relationship is unclear. We aimed to examine the associations between fruit, vegetable, seafood, and dairy intake and type 2 diabetes prevalence in a Chinese population.A total of 4,343 individuals aged 35-74 years participated in a population-based cross-sectional study in Qingdao, China. The frequency and quantity of fruit, vegetable, seafood, and dairy intake were determined using a standard food frequency questionnaire. Diabetes was classified according to the WHO/IDF 2006 criteria. Logistic regression analysis was employed to estimate odds ratio (OR) for type 2 diabetes in relation to fruit, vegetable, seafood, and dairy intake in a multivariable model.The multivariate-adjusted ORs (95% confidence interval) for the presence of type 2 diabetes were 0.68 (0.46-0.98), 0.50 (0.37-0.68), and 0.91 (0.66-1.25), respectively, for the highest versus the lowest groups regarding total fruit and vegetable, fruit or vegetable intake in women. The ORs for type 2 diabetes prevalence regarding the quantity of fruit and vegetable, fruit, and yogurt intake were 0.88 (0.78-0.99), 0.71 (0.61-0.82), and 0.56 (0.32-0.98) in women, but not in men. Seafood consumption was inversely associated with diabetes risk in men, but not in women; the corresponding figures were 0.58 (0.35-0.96) and 0.92 (0.63-1.36), respectively.Fruit, vegetable, and yogurt intake in women and seafood intake in men were inversely associated with type 2 diabetes prevalence in this Chinese population. These findings require confirmation in a prospective study.

Composite of nanoscale Zero Valent Iron (nZVI) loaded on Biochar (BC) was prepared and characterized as hydrogen peroxide (H2O2) activator for the degradation of trichloroethylene (TCE). nZVI is homogeneously loaded on lamellarly structured BC surfaces to form nZVI/BC with specific surface area (SBET) of 184.91 m2 g−1, which can efficiently activate H2O2 to achieve TCE degradation efficiency of 98.9% with TOC removal of 78.2% within 30 min under the conditions of 0.10 mmol L−1 TCE, 1.13 g L−1 nZVI/BC and 1.50 mmol L−1 H2O2. Test results from the Electron Spin Resonance (ESR) measurement and coumarin based fluorescent probe technology indicated that ∙OH radicals were the dominant species responsible for the degradation of TCE within the nZVI/BC-H2O2 system. Activation mechanism of the redox action of Fe2+/Fe3+ generated under both aerobic and anaerobic conditions from nZVI and single electron transfer process from BC surface bound C–OH to H2O2 promoted decomposition of H2O2 into ∙OH radicals was proposed.

Aims To estimate the long-term cost-effectiveness of exenatide twice daily vs insulin glargine once daily as add-on therapy to oral antidiabetic agents (OADs) for Chinese patients with type 2 diabetes (T2DM). Methods The Cardiff Diabetes Model was used to simulate disease progression and estimate the long-term effects of exenatide twice daily vs insulin glargine once daily. Patient profiles and treatment effects required for the model were obtained from literature reviews (English and Chinese databases) and from a meta-analysis of 8 randomized controlled trials comparing exenatide twice daily with insulin glargine once daily add-on to OADs for T2DM in China. Medical expenditure data were collected from 639 patients with T2DM (aged ≥18 years) with and without complications incurred between January 1, 2014 and December 31, 2015 from claims databases in Shandong, China. Costs (2014 Chinese Yuan [¥]) and benefits were estimated, from the payers’ perspective, over 40 years at a discount rate of 3%. A series of sensitivity analyses were performed. Results Patients on exenatide twice daily + OAD had a lower predicted incidence of most cardiovascular and hypoglycaemic events and lower total costs compared with those on insulin glargine once daily + OAD. A greater number of quality-adjusted life years (QALYs; 1.94) at a cost saving of ¥117 706 gained was associated with exenatide twice daily vs insulin glargine once daily. (i.e. cost saving of ¥60 764/QALY) per patient. Conclusions In Chinese patients with T2DM inadequately controlled by OADs, exenatide twice daily is a cost-effective add-on therapy alternative to insulin glargine once daily, and may address the problem of an excess of medical needs resulting from weight gain and hypoglycaemia in T2DM treatment.

Dynamic stiffness and damping of the headstock, which is a critical component of precision horizontal machining center, are two main factors that influence machining accuracy and surface finish quality. Constrained Layer Damping (CLD) structure is proved to be effective in raising damping capacity for the thin plate and shell structures. In this paper, one kind of high damping material is utilized on the headstock to improve damping capacity. The dynamic characteristic of the hybrid headstock is investigated analytically and experimentally. The results demonstrate that the resonant response amplitudes of the headstock with damping material can decrease significantly compared to original cast structure. To obtain the optimal configuration of damping material, a topology optimization method based on the Evolutionary Structural Optimization (ESO) is implemented. Modal Strain Energy (MSE) method is employed to analyze the damping and to derive the sensitivity of the modal loss factor. The optimization results indicate that the added weight of damping material decreases by 50%; meanwhile the first two orders of modal loss factor decrease by less than 23.5% compared to the original structure.

This paper presents a general and systematic approach for geometric error modeling of machine tools due to the geometric errors arising from manufacturing and assembly. The approach can be implemented in three steps: (1) development of a linear map between the pose error twist and source errors within machine tool kinematic chains using homogeneous transformation matrix method; (2) formulation of a linear map between the pose error twist and the error intensities of a machine tool; (3) combination of these two models for error separation. The merit of this approach lies in that it enables the source errors affecting the compensatable and uncompensatable pose accuracy of the machine tool to be explicitly separated, thereby providing designers and/or field engineers with an informative guideline for the accuracy improvement by suitable measures, i.e. component tolerancing in design, manufacturing and assembly processes, and error compensation. Two typical multi-axis machine tools are taken as examples to illustrate the generality and effectiveness of this approach.

To examine and compare health-related quality of life (HRQoL) in people with previously known diabetes, new screen-detected asymptomatic diabetes and people without diabetes. HRQoL of 4,613 individuals who participated in a population-based cross-sectional diabetes survey in Qingdao, China, in 2009, was assessed using the 15D instrument. A Tobit regression model to estimate the effects of diabetes on HRQoL separate from effects of other health determinants was constructed. Among the surveyed population, 220 (4.8 %) individuals had previously known diabetes and 531 (11.5 %) individuals had new screen-detected diabetes, defined by fasting plasma glucose ≥7.0 mmol/l and/or 2-h plasma glucose ≥11.1 mmol/l. The age-, gender-, and BMI-adjusted mean 15D score of people without diabetes, with new screen-detected diabetes, and previously known diabetes was 0.975, 0.975, and 0.964, respectively, for urban and 0.971, 0.972, and 0.960, respectively, for rural participants. HRQoL overall and on all the dimensions (p

To improve the efficiency of acquiring monitored features and present a reliable quality assessment method for resistance spot welding, a novel method for converting the electrode displacement signal into binary image is proposed. The probabilistic neural network is adopted to provide a probabilistic viewpoint and a deterministic classification result of weld quality when the image characteristic of displacement signal is selected as monitored features. Test results of the classifier demonstrate that it is feasible and reliable to utilise binary image of the displacement signal to evaluate weld quality. The method reserves weld quality information as much as possible and it avoids complex algorithm for extracting and selecting monitored features. At the same time, when there are small samples, the classifier can identify good or bad weld rapidly and accurately even though the weld is from abnormal welding process, such as expulsion, current shunting and small edge distance condition.

Geometric error modeling and its sensitivity analysis are carried out in this paper, which is helpful for precision design of machine tools. Screw theory and rigid body kinematics are used to establish the error model of an RRTTT-type five-axis machine tool, which enables the source errors affecting the compensable and uncompensable pose accuracy of the machine tool to be explicitly separated, thereby providing designers and/or field engineers with an informative guideline for the accuracy improvement by suitable measures, that is, component tolerancing in design, manufacturing, and assembly processes, and error compensation. The sensitivity analysis method is proposed, and the sensitivities of compensable and uncompensable pose accuracies are analyzed. The analysis results will be used for the precision design of the machine tool.

The free transverse vibration characteristics of cantilevered boron nitride nanocones (BNNCs) have been systematically investigated by utilising classic molecular dynamics simulations. The natural frequencies of the transverse vibrations of cantilevered BNNCs with different apex angles, cone heights and top radii are achieved by using fast Fourier transformation. The influences of the geometric parameters of the BNNCs on the natural frequencies are extensively investigated based on the established methodology.

Plane wave pseudopotential (PWP) density functional theory (DFT) calculation is the most widely used method for material simulations, but its absolute speed stagnated due to the inability to use large scale CPU based computers. By a drastic redesign of the algorithm, and moving all the major computation parts into GPU, we have reached a speed of 12s per molecular dynamics (MD) step for a 512 atom system using 256GPU cards. This is about 20 times faster than the CPU version of the code regardless of the number of CPU cores used. Our tests and analysis on different GPU platforms and configurations shed lights on the optimal GPU deployments for PWP-DFT calculations. An 1800 step MD simulation is used to study the liquid phase properties of GaInP.

To study joint effect of family history of diabetes (FHD) with obesity on prevalence of type 2 diabetes mellitus in the Chinese and in the Finns.A total of 1091 Chinese men and 1706 women, 1472 Finnish men and 1694 women, 45-74 years of age were studied. The probability and odds ratio (OR) of having diabetes were estimated using logistic regression analysis. The synergy index (SI) and relative excess risk due to interaction (RERI) of FHD with body mass index (BMI) or waist circumference (WC) was calculated.Age-standardized prevalence of diabetes was higher in individuals with FHD than in those without in both the Chinese and Finns. Compared with individuals without FHD and with BMI30 kg/m(2), ORs (95% confidence intervals [CI]) for diabetes were 2.7 (1.8, 4.0), 2.8 (1.9, 4.0), 9.1 (5.9, 13.9), respectively, in Finnish men with BMI ≥30 kg/m(2) alone, with FHD alone and with both (SI [95% CI] = 2.4 [1.4, 3.9], RERI = 4.6 [1.3, 8.0]); the corresponding figures were 1.7 (1.0, 2.9), 2.7 (1.8, 4.2) and 4.4 (1.9, 10.4) in Chinese men (SI = 1.4 [0.4, 4.9] RERI = 1.0 [-2.9, 5.0]). They were 3.5 (2.1, 5.8), 2.1 (1.3, 3.4) and 6.8 (4.1, 11.2) in Finnish women (SI = 1.6 [0.9, 2.8], RERI = 2.2 [-0.4, 4.9]), and 1.6 (1.1, 2.2), 2.1 (1.5, 3.0), 3.5 (1.9, 6.4) in Chinese women (SI = 1.5 [0.6, 3.8], RERI = 0.8 [-1.4, 3.0]). The pattern of synergistic effect of FHD with WC on diabetes was similar to that seen with BMI in the Finns but no effect was seen in the Chinese.Both obesity and FHD are independent risk factors for diabetes, but their joint effect is significant only in Finnish men.

a b s t r a c t Plane wave pseudopotential (PWP) density functional theory (DFT) calculation is the most widely used material science simulation, and the PWP DFT codes are arguably the most important material science codes. We have implemented a PWP DFT code PEtot on a multi-node GPU machine. Starting from a previous work, we have further improved the speed of the code, and achieved x13-x22 speedups over the CPU calculations for a typical 512 atom system. Such speedups are much higher than other similar works for this important class of material simulation codes on GPU clusters. The current achievement is obtained by (1) moving the calculation fully into the GPU; (2) adopting a new algorithm to reduce the data amount for MPI communication; and (3) using new GPU and CPU numerical libraries. We have also provided a detail quantitative analysis of the computational times for different physical systems and number of GPU units, which helps one to understand the challenges and bottlenecks of the PWP DFT simulations on GPU machines. Based on the analysis, we listed the machine and library requirements in order to further improve the performances of the PWP DFT calculations.

Aims To evaluate costs and effectiveness of implementing a diabetes self-risk assessment (Diabetes Risk Score) questionnaire coupled with a multimedia health promotion campaign on changes in diabetes awareness in a large diabetes prevention programme. Methods Between 2007 and 2010, a multimedia health promotion campaign was conducted targeting the 1.94 million population of Qingdao, China, using newspapers, radio programmes, distribution of free booklets and Diabetes Risk Score flyers. Diabetes awareness questionnaires filled out by people first interviewed in 2006 (survey A), before the initiation of the campaign, were compared with those first interviewed between 2007 and 2010 during the campaign period (survey B). The rates of diabetes awareness in both surveys were studied amongst adults aged 35–74 years without a prior history of diabetes, but with a Diabetes Risk Score of ≥ 14. Results In survey B, 85, 82 and 76% of the urban participants correctly recognized obesity, family history of diabetes and physical inactivity, respectively, as important risk factors for diabetes; while the awareness rates were 43, 46 and 25%, respectively, in survey A (P

The milling stability of thin-walled component is an important problem in the aviation manufacturing industry. The milling stability is influenced by both deflection characteristic and dynamic characteristic of workpiece. Moreover, in the material removal, the deflection and dynamic characteristics of workpiece are time-variant on the change of machining positions. Thus, the milling stability is also time-variant. In order to investigate the time variation of deflection and dynamic characteristics of workpiece, a new computational model was established in this paper. Based on the influences of the deflection and the dynamic characteristics of workpiece, a new stability lobes diagram which can show different stability domains and chatter domains in different process positions was obtained. Experimental testing has been conducted to validate the established new model.

Complicated skin and soft tissue infections (cSSTI) are some of the most commonly treated infections in hospitals, and place heavy economic burdens on patients and society. Here we report the findings from an analysis of cSSTI based on a retrospective study which was conducted within the Chinese inpatient population. We focused our research on the analysis of the patient population, antibiotic treatment, clinical outcome and economic burden. The study population comprised 527 selected patients hospitalized between 2008 and 2013. Among the hospitalizations with microbiological diagnoses, 61.41% (n = 113) were diagnosed as infected with Gram-positive bacteria, while 46.20% (n = 85) were infected with Gram-negative bacteria. The most commonly found Gram-positive bacteria was Staphylococcus aureus (40.76%, n = 75), and the most common Gram-negative bacteria was Escherichia coli (14.13%, n = 26). About 20% of the Staphylococcus aureus were methicillin-resistant. The resistance rate of isolated Staphylococcus aureus or Escherichia coli to penicillin was around 90%; in contrast, the resistance rate to vancomycin, linezolid or imipenem was low (

Updating parameters according to the driving rate of input, the rate-dependent Prandtl-Ishlinskii (PI) model is widely used in hysteresis modeling and compensation. In order to improve the modeling accuracy, two PI models identified at low and high driving rates separately are incorporated through a combination law. For the piezo-driven flexure-based mechanism, the very low damping ratio makes it easy to excite the structural vibration. As a result, the measured hysteresis loop is greatly distorted and the modeling accuracy of the identified PI model is significantly affected. In this paper, a novel time-efficient parameter identification method which utilizes the superimposed sinusoidal signals as the control input is proposed. This method effectively avoids the excitation of the structural vibration. In addition, as the driving rate of the superimposed sinusoidal signals covers a wide range, all the coefficients required for modeling the rate-dependence can be identified through only one set of experimental data. Hysteresis modeling and trajectory tracking experiments were performed on a 2-DOF piezo-driven flexure-based mechanism. The experimental results show that the combined hysteresis model maintains the modeling accuracy over the entire working range of the flexure-based mechanism. The mechanism’s hysteresis is significantly suppressed by the use of the inverse PI model as the feedforward controller; and better result is achieved when a feedback loop is also incorporated. The tracking performance of the flexure-based mechanism is greatly improved.

Complicated intra-abdominal infection (cIAIs) are a common and important cause of morbidity worldwide. In this study, the clinical features, microbiological profiles, antimicrobial patterns and treatments of 3233 cIAI patients (mean age, 47.6 years; 54.7% male) with 3531 hospitalisations from 2008–2013 were retrospectively investigated. The most commonly isolated bacteria were Escherichia coli (47.6%), Klebsiella pneumoniae (16.9%), Enterococcus faecalis (10.4%) and Pseudomonas aeruginosa (8.8%). Ciprofloxacin, aminoglycoside (gentamicin), piperacillin/tazobactam and carbapenems exhibited activity against 53%, 76%, 88% and 100% of extended-spectrum β-lactamase (ESBL)-positive Enterobacteriaceae isolates, respectively. Pseudomonas aeruginosa isolates exhibited 100%, 95%, 88%, 71% and 76% susceptibility to aminoglycoside (gentamicin), ciprofloxacin, meropenem, imipenem and ceftazidime, respectively, and Enterococcus remained 100% susceptible to vancomycin and linezolid. β-Lactam antibacterials other than penicillin (specifically third-generation cephalosporins) and imidazole derivatives (ornidazole and metronidazole) were the most common first-line treatments. Patients subjected to regimen change after initial antibiotic treatment had predisposing conditions (e.g. older age, more severe co-morbidities) and a higher incidence of P. aeruginosa infection; in addition, these patients encountered a higher average cost of care and worse clinical outcomes compared with those without medication modification. Taken together, these findings indicate the importance of appropriate initial empirical therapy and suggest the use of combination therapy comprising cephalosporins and metronidazole.

In this paper, eddy current sensors and thermocouple sensors were employed to measure the thermal field and thermal deformation of a spindle of a telescopic CNC boring-milling machine tool, respectively. A linear regression method was proposed to establish the thermal error model. Furthermore, two compensation methods were implemented based on the SIEMENS 840D system by using the feed shaft of z direction and telescopic spindle respectively. Experimental results showed that the thermal error could be reduced by 73.79% when using the second compensation method, and the thermal error could be eliminated by using the two compensation methods effectively.

The projection method based on the Schauder basis expansion for solving the Fredholm integral equation of the second kind is investigated. (1) It is shown that any given finite linearly independent function set in Lp[0, 1] can be extended as a Schauder basis. The truncation of the dual Schauder bases is then used to form the projection in approximating the kernel. (2) With the finite rank approximation, the use of the Sherman-Morrison-Woodbury formula achieves efficient implementation. The computation is successive when dimension of projection space increases. Numerical experiments demonstrate the robustness of the Schauder basis expansion.

Due to its high overpotential and low efficiency, the conversion of water to O(2) using solar energy remains a bottleneck for photocatalytic water splitting. Here the microscopic mechanisms of the oxygen evolution reaction (OER) on differently structured anatase surfaces in aqueous surroundings, namely, (101), (001), and (102), are determined and compared systematically by combining first-principles density functional theory calculations and a parallel periodic continuum solvation model. We show that OER involves the sequential removal of protons from surface oxidative species, forming surface peroxo and superoxo intermediates. The initiating step, the first proton removal, dictates the high overpotential. Only at an overpotential of 0.7 V (1.93 V vs SHE) does this rate-controlling step become surmountable at room temperature: the free energy change of the step is 0.69, 0.63, and 0.61 eV for (101), (102), and (001) surfaces, respectively. We therefore conclude that (i) OER is not sensitive to the local surface structure of anatase and (ii) visible light (∼590 nm) is, in principle, capable of driving the photocatatlytic OER on anatase kinetically. By co-doping high-valent elements into the anatase subsurface, we demonstrate that the high overpotential of the OER can be significantly reduced, with extra occupied levels above the valence band.

The rotational performance of the spindle-bearing system has critical influence upon the geometric shape and surface roughness of the machined parts. The effects of preload and preload method on the rotational performance of the spindle-bearing system is explored experimentally to reveal the role of preload and preload method in spindle rotational performances under different speeds. A test rig on which both the rigid preload and elastic preload can be realized, equipped with variable preload spindle-bearing system, is developed. Based on the mechanical model, the relationship of the axial preload and negative axial clearance of the spindle-bearing system is provided. Rotating sensitive radial error motion tests are conducted for evaluating synchronous and asynchronous radial errors of the variable preload spindle-bearing system under different rotating speeds and preload methods. The change regularity of synchronous and asynchronous radial errors with preloads under different rotating speeds are given. The results show that the preload plays an important role on the rotational performance of spindle-bearing system. The rigid preload is more efficient in achieving better rotational performance than elastic preload under the same rotating speed. Furthermore, this article significantly guides the preload designing and assembling of the new spindle-bearing system.