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Background: The role of Eintraoperative joint organ removal or transit abdominal surgery recovery after surgery (ERAS) in reducing hospital stay time and perioperative hospitalization costs have been proven. However, most studies have been carried out in areas rich in medical resources. In this study, we evaluated the safety and efficacy of ERAS compared with traditional perioperative period care for laparoscopic cholecystectomy (LC) in areas poor in medical resources in China. Methods: A randomized controlled trial on laparoscopic cholecystectomy was conducted at The People's Hospital of Fengqing from July 2020 to March 2021. Patients were randomly divided into an ERAS group and a traditional care group. The main outcome was the length of hospital stay after surgery. The secondary outcomes included hospitalization costs and visual analogue scale (VAS) scores for postoperative pain, first exhaust time, and first semi-liquid diet time after surgery. The ERAS group was provided with perioperative education, nutritional support, preoperative 2 h oral carbohydrates, restricted rehydration, intraoperative insulation, no drainage tubes, wound hemp, early mobilization postoperative nausea and vomiting (PONV) prevention and multi-modal analgesia, early activity. Results: The study was conducted on a total of 140 patients with 70 patients each in the ERAS group and traditional care groups. In the ERAS group, The length of hospital stay after surgery was shorter (4.06 vs.4.61 days, P0.05) was observed between the two groups. Conclusion:Even in areas poor in medical resources in China, the use of the ERAS concept for LC surgery can reduce the length of hospital stay, cut down the cost of hospitalization, and lessen the pain of patients after surgery and accelerate postoperative recovery.

Through the forming of large and thick sheet metal cylindrical parts, it was found that symmetrical abnormal arching defects appeared at both ends of the first and tail ends in the length direction. In response to this phenomenon, the finite element simulation verification and comparison of the two processes of multi-point mold forming and integral mold forming are carried out. The analysis results show that this kind of end effect exists in both the multi-point mold forming and the overall mold forming process, and the overall mold forming effect is better. The multi-point mold has a small springback in the length direction, which is versatile and compatible.

In this paper, the cold extrusion process of aluminum alloy with multi-ribs was studied. The target part is formed by one-step closed cold extrusion. It has the advantages of simple process and high material utilization. The effects of extrusion speed and die corner on forming force and contact stress between billet and die were analyzed. According to the simulation results under different conditions, the reasonable process parameters are selected to obtain the products with full shape and without obvious defects. It can provide an effective reference for the parameter design in the cold extrusion process of this kind of multi-ribs parts.

Background: The role of Eintraoperative joint organ removal or transit abdominal surgery recovery after surgery (ERAS) in reducing hospital stay time and perioperative hospitalization costs have been proven. However, most studies have been carried out in areas rich in medical resources. In this study, we evaluated the safety and efficacy of ERAS compared with traditional perioperative period care for laparoscopic cholecystectomy (LC) in areas poor in medical resources in China.Methods: A randomized controlled trial on laparoscopic cholecystectomy was conducted at The People's Hospital of Fengqing from July 2020 to March 2021. Patients were randomly divided into an ERAS group and a traditional care group. The main outcome was the length of hospital stay after surgery. The secondary outcomes included hospitalization costs and visual analogue scale (VAS) scores for postoperative pain, first exhaust time, and first semi-liquid diet time after surgery. The ERAS group was provided with perioperative education, nutritional support, preoperative 2 h oral carbohydrates, restricted rehydration, intraoperative insulation, no drainage tubes, wound hemp, early mobilization postoperative nausea and vomiting (PONV) prevention and multi-modal analgesia, early activity.Results: The study was conducted on a total of 140 patients with 70 patients each in the ERAS group and traditional care groups. In the ERAS group, The length of hospital stay after surgery was shorter (4.06 vs.4.61 days, P0.05) was observed between the two groups.Conclusion: Even in areas poor in medical resources in China, the use of the ERAS concept for LC surgery can reduce the length of hospital stay, cut down the cost of hospitalization, and lessen the pain of patients after surgery and accelerate postoperative recovery.

According to the profile processing, two forming processes are proposed, i.e., multi-point stamping forming and multi-point stretch forming. Through the finite element simulation, two forming processes are simulated and compared. The analysis results show that the longitudinal springback and transverse forming error of parts by multi-point stretch forming are smaller than those by multi-point stamping forming, so the multi-point stretch forming process is suitable for processing this kind of aluminum alloy profile.

Cerebral small vessel disease (CSVD) is a clinically commonly-seen slow-progressing cerebral vascular disease. As a classic Chinese formula for the treatment of stroke, Daqinjiao Decoction (DQJD) is now used to treat CSVD with desirable effect. Since the mechanism of action is still unclear, this article will explore the therapeutic effect and mechanism of action of the formula using network pharmacology technology.The major chemical components and potential target genes of DQJD were screened by bioinformatics. The key targets in CSVD were identified based on network modules. Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed. Pharmacodynamics of the decoction was evaluated by establishing a rat model with bilateral common carotid artery occlusion in the brain. Molecular docking, Western blot analysis and quantitative real-time polymerase chain reaction (QRT-PCR) were performed to confirm the effectiveness of targets in related pathways.Network pharmacology showed that 16 targets and 30 pathways were involved in the DQJD-targeted pathway network. Results revealed that DQJD might play a role by targeting the key targets including Caspse3 and P53 and regulating the P53 signaling pathway. Cognitive function and neuronal cell changes of rats were evaluated using Morris water maze, open field test and HE staining. It was indicated that DQJD could keep the nerve cells intact and neatly arranged. The decoction could improve the memory and learning ability of rats compared with the model group. It decreased the protein and mRNA expression levels of Caspse3 and P53 significantly (p0.01).The study shows that baicalein, quercetin and wogonin, the effective components of DQJD, may regulate multiple signaling pathways by targeting the targets like Caspse3 and P53 and treat CSVD by reducing the damage to brain nerve cells.

In this work, the high-strength Mg–5Zn–2Al–2Sn (ZAT522, in wt%) Mg alloys was obtained at 220 °C and 130 °C by a two-step equal channel angular pressing (ECAP). For each stage, two passes were used. The results showed a remarkable grain refinement after the first stage of ECAP (A2 samples), leading to a fine-grained structure with average size of 1.40 μm. The additional stage (A4 samples) caused further grain refinement to 1.18 μm, and an ultra-fine grain structure (700 nm) appeared in the precipitate-rich region. The grain refinement mechanism for both samples was discussed in detail. To this end, the original extrusion fiber texture evolved into a new strong texture characterized by the base planes tilted toward the ECAP shear plane, with a higher Schmid factor value of 0.34. Compared with the as-extruded alloy, the yield strength of the A2 samples increased from 180 to 245 MPa, which was mainly attributed to the combined effects of grain boundary strengthening and precipitation strengthening. In the case of A4 samples, the dislocation strengthening resulted in a net increase in yield strength to 335 MPa, while the ductility was significantly reduced.

Bacterial infections have become major threats to public health all over the world. With the emergence of antibiotic resistance, it is urgent to develop novel antimicrobial materials to efficiently overcome drug resistance with high bactericidal activity. In this work, UiO-66-NH-CO-MoS

The advantages of multi-point warm press forming Corian sheet are fewly studied. In this study, the principle of multi-point warm press forming process and the geometrical relationship between multi-point punch elements and objective surface were firstly illustrated. The multi-point CAD/CAM software was used for punch height calculation and punch location adjustment. The effects of elastic cushion, forming temperature and forming force on the forming accuracy, were studied through multi-point warm press forming experiments. Then, the Corian sheets for spherical and saddle-shaped parts based on suitable forming parameters were formed through multi-point warm press forming process, and the shape errors between experimental parts and objective ones were compared. The high surface quality and shape accuracy of both spherical and saddle-shaped parts were obtained at 165 °C with the forming force of 100 kN. It confirms that the multi-point warm press forming process is feasible for manufacturing Corian sheets.

Springback is an inevitable phenomenon in multi-point forming, it affects the forming accuracy seriously. The precision of formed parts can be improved by modifying the die profile. The method of springback compensation for multi-point dies which formed cylindrical parts was studied utilizing theoretical analysis, numerical simulations and experiments. In order to accurately form cylindrical parts with specified parameters, the springback compensation formula of multi-point dies was studied. The upper and lower dies were adjusted according to the formula. Comparing the formed parts obtained from numerical simulation and experiment with the target part, the results show that this method can control the forming error within 1 mm guiding the forming process of cylindrical parts in practice, the problem of shape error caused by springback was solved effectively.

Flexible-bending is an advanced bending method, especially suitable for small batch production of tubes. The shape of forming parts is mainly related to the offset of the bend die instead of the geometry of it. Based on flexible-bending technology, 3D bending of tubes was carried out by finite element method and the effects of primary parameters on the bending results were studied. The analysis results showed that3D continuous bending of tubes can be obtained by flexible-bending process; die offset, offset speed and feeding speed of tube have a great influence on the bending effect. Bending experiments of 3D tube were carried out by flexible-bending equipment and bending radii of the forming part were measured, the results were very close to that of simulations which proved the effectiveness of simulation.

Bacterial infections have become major threats to public health all over the world. With the emergence of antibiotic resistance, it is urgent to develop novel antimicrobial materials to efficiently overcome drug resistance with high bactericidal activity. In this work, UiO-66-NH-CO-MoS2 nanocomposites (UNMS NCs) are constructed through the amidation reaction. The UNMS NCs are positively charged which is beneficial for capturing and restricting bacteria. Significantly, UNMS NCs possess a synergistic bactericidal efficiency based on near-infrared irradiation (808 nm) regulated combination of photothermal, photodynamic, and peroxidase-like enzymatic activities. Both the photodynamic property and nanozymatic activity of UNMS NCs can lead to the generation of reactive oxygen species. The UNMS NCs show high catalytic activity in a wide pH range and exhibit excellent antibacterial ability against ampicillin-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus with negligible cytotoxicity. Interestingly, due to the 808 nm irradiation-induced hyperthermia in the presence of UNMS NCs, the glutathione oxidation process can be accelerated, resulting in bacterial death more easily. Mice wound models are established to further manifest that UNMS NCs can promote wound healing with good biosafety in living systems.

Unlike multi-point die forming (MPDF), multi-point press forming (MPPF) takes full advantage of the flexibility of multi-point forming (MPF). In the process of MPPF, the punch elements always keep in contact with the sheet metal, developing instantaneous forming surfaces, which clamp and deform the plates. In this study, based on the spherical surfaces, the formability of both MPPF and MPDF were simulated through finite element software. The effects of the two methods on dimple, wrinkle and springback defect were comparatively analyzed. Also the shape error of MPPF was studied. We find MPPF can significantly inhibit dimple and wrinkle, thus obviously reducing the maximum strain and homogenizing the distributions of stress and strain of the parts. The largest vertical springback value decreases from 0.514mm to 0.257mm and the stress is released more completely after unloading. The edge effect reduces the curvature in the area far away from the center, greatly magnifying the shape error. The increase in the numbers of punch elements and in the dimensions of elastic cushions can significantly weaken the edge effect and improve the forming precision. These analyses show MPPF has better formability for metal sheets than MPDF.

The design and experiment test on the strain clamp and the splicing sleeve of the 1520 mm2 large section conductor have been carried out in this paper. It is calculated that grip force is in accordance with 95% and 90.25% of conductor rated tensile force through grip force experiment analysis. Critical values of the effective compression length of the strain clamp and the splicing sleeve of the 1520 mm2 large section conductors are obtained through several tests and optimization. The effective compression length is recommended to take 6D; the inner diameter of the aluminum tube is applied to take 3D. For the aluminum alloy core profile aluminum conductor, the compression material of the aluminum alloy core selects the 3A21 aluminum alloy tube, tensile strength of the 3A21 aluminum alloy is 135MP and the elongation rate is 20%.

Acute sympathetic stress causes excessive secretion of catecholamines and induces cardiac injuries, which are mainly mediated by β-adrenergic receptors (β-ARs). However, α1-adrenergic receptors (α1-ARs) are also expressed in the heart and are activated upon acute sympathetic stress. In the present study, we investigated whether α1-AR activation induced cardiac inflammation and the underlying mechanisms. Male C57BL/6 mice were injected with a single dose of α1-AR agonist phenylephrine (PE, 5 or 10 mg/kg, s.c.) with or without pretreatment with α-AR antagonist prazosin (5 mg/kg, s.c.). PE injection caused cardiac dysfunction and cardiac inflammation, evidenced by the increased expression of inflammatory cytokine IL-6 and chemokines MCP-1 and MCP-5, as well as macrophage infiltration in myocardium. These effects were blocked by prazosin pretreatment. Furthermore, PE injection significantly increased the expression of NOD-like receptor protein 3 (NLRP3) and the cleavage of caspase-1 (p20) and interleukin-18 in the heart; similar results were observed in both Langendorff-perfused hearts and cultured cardiomyocytes following the treatment with PE (10 μM). Moreover, PE-induced NLRP3 inflammasome activation and cardiac inflammation was blocked in Nlrp3-/- mice compared with wild-type mice. In conclusion, α1-AR overactivation induces cardiac inflammation by activating NLRP3 inflammasomes.

Word sense disambiguation (WSD) is an important and hot research topic in machine translation and information retrieval. A new WSD method is proposed in this paper. Chinese sentence containing ambiguous word is segmented into words. Its left and right words’ semantic categories are used as disambiguation features after Tongyici Cilin is consulted. Based on discriminative features, bayesian model is applied to select correct semantic categories for ambiguous words. Training data set is used to optimize bayesian model and test data set is utilized to test the performance of WSD classifier. Experiments show that accuracy of WSD classifier is improved.

Flexible rolling is suitable to manufacture small batch of 3D curvature parts with various shapes. In this paper, the influence of end effect on saddle curved part was studied firstly. The finite element model was designed based on the flexible rolling forming apparatus. The areas characteristics of forming saddle curved part were analysed, and the influence of end effect on the saddle curved part with different forming size was studied. The results demonstrate that: the forming saddle curved part consists of three forming areas by characteristics, and the forming mechanism of each forming area is analyzed deeply; under the end effect action, with the sheet length increases, the plastic strain and minimum forming thickness of forming curved part are stable; when the sheet length is 200mm, 300mm, 400mm and 500mm, the percent of the stable forming area of forming curved part is 52%, 72%, 79% and 83% respectively, and the percent of stable forming area increases by 20%, 27%, 31% respectively, therefore the utilization rate is obviously improved. With the increasing sheet width, the plastic strain is increasing and the minimum forming thickness is decreased; when the sheet width is 85mm, 90mm, 95mm and 100mm, the percent of stable forming area of forming curved part is 67%, 61%, 59%, 58% respectively, and the percent of stable forming area decreases by 6%, 8%, 9% respectively, therefore the utilization rate is decreasing.

Periodontal ligament stem cells (PDLSCs) are tissue-specific mesenchymal stem cells (MSCs), having an important role in regenerative therapy for teeth loss. Interleukin-7 (IL-7) is a key cytokine produced by stromal cells including MSCs, and exhibits specific roles for B and T cell development and osteoblasts differentiation of multiple myeloma. However, the effect of IL-7 on osteogenic differentiation of PDLSCs remains unclear. Therefore, in the present study we determined whether IL-7 affects the proliferation and osteogenic differentiation of PDLSCs in vitro and explored the associated signaling pathways for IL-7-mediated cell differentiation. The results demonstrated that the isolated human PDLSCs possessed MSCs features, highly expressing CD90, CD44, CD105, CD29 and CD73, and almost did not expressed CD34, CD45, CD11b, CD14 and CD117. IL-7 could not significantly affect the proliferation of PDLSCs, but it decreased their osteogenic differentiation and inhibited alkaline phosphatase (ALP) activity. The results of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting exhibited that the expression levels of Runx-2, SP7 and osteocalcin (OCN) were significantly reduced by IL-7. Further studies indicated that IL-7 did not significantly change JNK, ERK1/2 and p38 protein production, but markedly suppressed their phosphorylation levels. These data suggest that IL-7 inhibits the osteogenic differentiation of PDLSCs probably via inactivation of mitogen-activated protein kinase (MAPK) signaling pathway.

The aim of this study was to investigate the effect of dietary supplementation of nanosize zinc on zinc digestibility, growth performances, immune response and serum parameters of weanling piglets. Ninety-six LYD weanling piglets were assigned to control, zinc oxide (ZnO), organic-Zn (Zn-methionine) and nanosize ZnO (nano-Zn) groups with four replicates. The zinc was at the 120 mg/kg level in the treatment group's diet, while the control group's was 80 mg/kg Zn. The experiment results indicated that the nano-Zn and organic-Zn groups had significantly higher Zn digestibility compared to the ZnO and control groups. For the immune response traits, the IgG level and goat red blood cells (GRBC) antibody titer were nano-Zn and organic-Zn>ZnO>control; in the phytohemagglutinin (PHA) challenge test result, nano-Zn>organic-Zn>ZnO>control; in regard to the γ-globulin level, nano-Zn and organic-Zn>ZnO and control, with significant difference between groups. In the serum parameters aspect, serum Zn concentration in nano-Zn and organic-Zn groups were higher than in the ZnO and control groups, serum growth hormone concentration was increased in the nano-Zn group than in the other groups. In conclusion, nanosize zinc oxide for dietary supplementation can increase zinc digestibility, serum growth hormone levels and carbonic anhydrase activity and enhance the immune response of weanling piglets.

3D rolling is a novel technology for three-dimensional surface parts. In this process, by controlling the gap between the upper and lower forming rolls, the sheet metal is non-uniformly thinned in thickness direction, and the longitudinal elongation of the sheet metal is different along the transverse direction, which makes the sheet metal generate three-dimensional deformation. In this paper, the transition zones of spherical surface parts in 3D rolling process are investigated. Spherical surface parts with the same widths but different lengths are simulated in condition of the same roll gap, and their experimental results are presented. The forming precision of forming parts and the causes of transition zones in the head and tail regions are analyzed through simulated results. The simulated and experimental results show that the lengths of transition zones of spherical surfaces in the head and tail regions are fixed values in condition of the same sheet width and roll gap.

The present study aims to investigate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on the osteogenesis of periodontal ligament (PDL) cells. The expression vector of rhBMP-2 (pcDNA3.1-rhBMP-2) was established. PDL cells were obtained through the enzymatic digestion and tissue explant methods and verified by immunohistochemistry. Cells were classified into experimental (cells transfected with pcDNA3.1/rhBMP-2-EGFP), blank (cells with no transfection) and control group (cells transfected with empty plasmid). rhBMP-2 expression was assessed via Western blotting analysis. The mineralization ability, alkaline phosphatase (ALP) activity and level of related osteogenic biomarkers were detected to evaluate the osteogenic characteristics of PDL cells. The rhBMP-2 expression vector (pcDNA3.1-rhBMP-2) was successfully established. Primary PDL cells displayed a star or long, spindle shape. The cultured cells were long, spindle-shaped, had a plump cell body and homogeneous cytoplasm and the ellipse nucleus contained two or three nucleoli. Cells displayed a radial, sheaf-like or eddy-like arrangement after adherence growth. Immunohistochemical staining confirmed that cells originated from mesenchymal opposed to epithelium. The experimental group exhibited an enhanced mineralization ability, higher ALP activity and increased expression of rhBMP-2 and osteogenic biomarkers (Runx2, collagen type I and osteocalcin) than the blank and control group. The present study demonstrated that rhBMP-2 transfection enhances the osteogenesis of PDL cells and provides a possibility for the application of rhBMP-2 expression products in dental disease treatment.

In the research of Delay Tolerant Network (DTN), DTN routing algorithm is a key research issue. The performance of a non-flooding routing algorithm is verified in our paper. The verified algorithm is an Adaptive Priority Routing Algorithm (APRA) which is based on fuzzy strategies. Firstly, we introduce the principle of APRA, then using Opportunistic Network Environment (ONE) -simulation software to compare the performance of Epidemic algorithm, Spray and Wait algorithm, PRoPHET algorithm and APRA. By comparing overhead of netword, rate of messages delivered and average dealy, it finds that the APRA performs better. At last, the weaknesses of this paper and further improvement are also discussed.

The finite element model of flexible clamp multi-point stretch forming (FCMPSF) was set up, and extensive contradistinctive analysis of forming limit and forming accuracy between FCMPSF and RCMPSF were done. The results show that under the same forming conditions, spherical part formed by FCMPSF is not easy to fracturing, dimpling and springback, and is easy to fit the die. The reason for this was analysed. The non-fracturing limited graph, the non-dimpling limited diagram and the average springback value of spherical parts formed by FCMPSF and RCMPSF were obtained. Finally, the forming experiment and error analysis of spherical part formed by FCMPSF were done, the results indicate that 3D parts with large transversal curvature can be shaped by FCMPSF and the forming quality was guaranteed.

Since spectral curves were obtained by experiment, on the basis of the fully use of the waveform characters, a new method for spectral matching pretreatment has been proposed in this paper. Corresponding to the spectral curve, we can accurately get the spectral absorption curve of the number of bands, it can effectively suppress the effects of the noise according to the times of fitting the points. Besides, it can also prominent the peak point of the material. This method can have an effective influence on the initial period of spectral match and detailed resolution; some numerical simulations have been made to test the validity and capability of the proposed method.

To solve the problem of low material utilization in traditional stretch forming process, a flexible stretch forming method was proposed, which can be realized by interaction of the multi-point stretch forming die with discrete-gripper stretch forming machine. The principle and characteristics of sheet metal flexible stretch forming technology was introduced, structural composition and working principle of the multi-point stretch forming die and discrete-gripper stretch forming machine were expounded, and the technology experiments was carried out with a self-designed flexible stretch forming technology equipment for sheet metal. The experimental results indicate that structure of multi-point stretch forming die and discrete-gripper stretch forming machine are reasonable, and flexible stretch forming technology can be realized by above-mentioned die and machine, stretch forming parts has a good quality and its shape error can satisfy requirements of production.

A visible difference exists between the measured Bidirectional Reflectance Distribution Function (BRDF) and the modeled BRDF. The Cook-Torrance model is chosen to simulate the BRDF for its popularity and flexibility. Taking aluminum for example, this paper analyzes the difference between the experiment data and the simulation data. There is a great and remarkable difference in the situation of specular reflection by comparison in this paper. Consequently, trigonometric factor, numerator and denominator addition factors and scaling factor are brought in the Cook-Torrance model. Finally, a modified Cook-Torrance model is presented. The simulation data of the modified Cook-Torrance model show that it’s more suitable for the analysis of the aluminum BRDF than the classic Cook-Torrance model.

Multi-gripper flexible stretch forming (MGFSF) is a recent technological innovation of sheet metal flexible forming process. Straight jaws in traditional stretch forming machine are replaced by a pair of opposed clamping mechanisms which can move relative to each other. Taking the case of forming a sheet metal into spherical surface by stretching the sheet in two opposite directions, the finite element models of MGFSF under various loading paths were established and the effects on stretch amount, strain and thickness of the simulated parts were analyzed comparatively. It is founded that compared to the horizontal-tilting (HT) and horizontal-vertical (HV) loading paths, the horizontal-tilting-vertical (HTV) loading path would result in more uniform stretch amount, strain and thickness distributions also with lower strain and thickness reduction, which improves the forming quality significantly. Finite element simulations also revealed that the material flow state in the transition zone can be improved effectively and the local strain concentration can be greatly suppressed with reasonable loading path, which would decrease the possibility of material failure.

Based on the multi-roller-pressing flexible stretch forming (MRPFSF) process, force loading and displacement loading were researched. The process of spherical parts of 08AL sheet material were simulated by means of an explicit finite element method. The variations of the forming force in stretch-forming process and the distribution of stress after springback were analyzed comparatively for both loading methods. The results show that the change of the forming force in the force loading method has fluctuation. With the depressing of rollers, the vibration amplitude is smaller. At the end of forming, the forming forces of both loading methods are gradually consistent. The stress distribution of spherical parts formed by the two loading method is accordant.

In this paper, we have discussed the principle of the flexible blank holder forming ( FBHF) technology, and established the finite element model of medal deep drawing process based on FBHF. Then we have discussed the FBHF technology by analyzing the system of finite element model. By simulating the forming of rectangular box, we can conclude that FBHF technology will have a greater advantage when the depth of stamping forming is much deeper. We have also compared the thickness distribution parameters, wrinkling parameters, and spring back parameters of rigid blank holder forming parts with FBHF parts. The result shows that the forming parts of FBHF technology has uniform stress and strain distribution, small spring back, the quality of inhibiting wrinkling, crack and other defects.

in this paper, we mainly introduce the principle of the flexible blank drawer forming (FBDF), and establish the limited element model of the FBDF process. Then we make a numerical analysis on the hemispherical parts, and study the effect made on the result of shaping by damping force, friction coefficient as well as material parameter in per unit area. Through the analysis of the numerical simulation result, we can conclude that the greater the yield limit and elasticity modulus, the larger blank drawer force is required to form the shape; the more smooth the material surface, the less resistance to deformation will have. All this contributes to good quality of forming parts.

The security of embedded systems has attracted much attention as they are being used in more and more fields in people’s life. Traditional technologies to protect the normal program execution are often software-based and they mainly focus on the protection of application code. In this paper, a hardware assisted framework is proposed to protect the program data validation at run-time. It divides the data into static data and dynamic data according to whether its values and spaces are constant or not. We extract the static data previously and get its validation information before the program runs. Since the information of static data stay constant during the execution, any deviation from it in the real-time data validation can be detected dynamically. Attacks to the integrity of dynamic data are defended by checking the data validation according to the store and load instructions at run-time. CRC algorithm is used in this proposal to compromise the security checking and resource consumption. The experimental result shows our proposed technique can protect program data validation with an acceptable resource overhead.

The content of characteristic pollutants including methyl tert-butyl ether (MTBE) and benzene, toluene, ethyl benzene, p-xylene, m-xylene and o-xylene (BTEX) were determined by head-space-GC. A HP-FFAP capillary column was used in this method. In the mass concentration range of 14.8μg·L-1~1760μg·L-1, there were good linearity relationships between the GC peak areas and the mass concentrations of components with correlation coefficient above 0.999.The detection limits were in the rage of 2.0μg·L-1~2.3μg·L-1. Tests for recoveries and precision were made by standard addition method, values of recoveries and RSDs (n=6) found were in the range of 95%~105% and 0.8%~5.5%.

Continuous roll forming is a new technology for manufacturing three-dimensional surface parts. Extensive numerical simulations of continuous roll forming process were carried out. The influence of the middle curve and the magnitude of the roll gap on the longitudinal curvature of formed parts is investigated. Wrinkling is one of the most important defects for the formed parts in continuous roll forming process. A simplified model was established for analyzing the wrinkling of saddle-shaped part and torus-shaped part. The simulated results show that the wrinkling of saddle-shaped part is located at the edges, and the wrinkling of torus-shaped part emerges in the vicinity of middle region.