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Product family (PF) is the most important part of product platform. A new method is proposed to mine PF based on multi-space product data in PLM database. Product structure tree (PST) and bill of material (BOM) are used as the data source. A PF can be obtained by mining physics space, logic space and attribute space of product data. In this work, firstly, a PLM database is described, consisting of data organization form, data structure, and data characteristics. Then the PF mining method introduces the sequence alignment techniques used in bio-informatics, which mainly includes data pre-processing, regularization, mining algorithm and cluster analysis. Finally, the feasibility and effectiveness of the proposed method are verified by a case study of high and middle pressure valve, demonstrating a feasible method to obtain PF from PLM database.

Product platform planning can greatly support product variant design, which is of great help to the implementation of mass customization (MC). In most of product platform planning methods, product modules and product families have been usually preplanned before products are designed, which would not make full use of the existing product resources. In this paper, we propose a method for product platform planning using the existing product data in product lifecycle management (PLM) database. The proposed method introduces two key technologies, i.e., pruning analysis and attribute matching. The pruning analysis is used to find out the sharing parts of different product families, which constitutes the basic framework of product platform; the attribute matching is used to classify product modules into different categories according to their sharing degrees, which reveals the relationships of different product modules and forms the association rules of product platform. The effectiveness of the proposed method is verified by the product data in the PLM database of a valve company. The proposed method greatly improves the reuse rate of existing product resources, providing an effective and fast way for enterprises to implement the MC strategy.

Cloud manufacturing (CMfg) has become a brand-new service-oriented networked manufacturing. The key technology that achieves this manufacture mode is to aggregate all kinds of potential CMfg services to create value-added composite CMfg services, so as to satisfy various manufacturing requirements. As massive CMfg services with the same manufacturing functionalities and different quality of service (QoS) are emerging on the Internet, CMfg services dynamic composition becomes more and more complex. One challenge of this technology is how to efficiently solve the problem of multipath CMfg services dynamic composition. Another challenge is how to conquer the overconstrained problem occurred in the process of CMfg services dynamic composition. To tackle these two issues, this paper proposes an approach for multipath CMfg services dynamic composition based on improved QoS constraint hierarchies (CHs) model. First, a QoS constraints description model with new evaluation function is propounded based on the CHs theory to conquer the overconstrained problem; second, improved max–min ant system (MMAS) is put forward by introducing improved transfer rule, new global pheromone updating rule and mutation mechanism into MMAS, and then an optimization algorithm named culture genetic MMAS is constructed for multipath CMfg services dynamic composition. Finally, experimental results and performance comparison prove that the proposed method is both effective and efficient.

Modular technology can effectively support the rapid design of products, and it is one of the key technologies to realize mass customization design. With the application of product lifecycle management (PLM) system in enterprises, the product lifecycle data have been effectively managed. However, these data have not been fully utilized in module division, especially for complex machinery products. To solve this problem, a product module mining method for the PLM database is proposed to improve the effect of module division. Firstly, product data are extracted from the PLM database by data extraction algorithm. Then, data normalization and structure logical inspection are used to preprocess the extracted defective data. The preprocessed product data are analyzed and expressed in a matrix for module mining. Finally, the fuzzy c-means clustering (FCM) algorithm is used to generate product modules, which are stored in product module library after module marking and post-processing. The feasibility and effectiveness of the proposed method are verified by a case study of high pressure valve.

The generalized module is one of the basic elements of parametric product platform, which can effectively support product variant design and mass customization design. A similarity analysis method for the non-isomorphism generalized module is proposed to support the precise configuration of product’s function, structure, and process. The structure, function, and process information of product modules are extracted from the product lifecycle management/product data management database and converted into eigenvector by range identification. Then, the parameters of different scales in non-isomorphism classes are normalized to eliminate the effect of different dimensions. The similarity measure of function and process information is completed by vector matching. The function equivalence classes and process equivalence classes are obtained using the proposed classification algorithms. The results of similarity analysis can increase the flexibility of product variant, meet the needs of customization, and thus directly support the precise configuration. Finally, the feasibility and effectiveness of the proposed method are verified by a case study of high and middle pressure valves.

Aiming at the PLM component library system, this paper studied the characteristic and requirement of the development of the PLM component. The main goal of this research include: deploying PLM component library using open source project OpenStack and KVM; studying the component communication method under heterogeneous environments on the basis of distributing framework model Remote Method Invocation (RMI); designing PLM soft component’s facet and interface; putting forward the steps of developing the distributed PLM component based on EJB technology (include Session Bean, Entity Bean, Message Bean); issuing distributed PLM component that is packed into Web service in order to achieve the mapping between PLM soft component and Web service by using J2EE Web service component; developing a PLM component library management system based on SOA framework.

To solve the problem of massive PLM product data analysis, a PLM product data analysis system based on OpenStack cloud platform was proposed.It includes a data analysis method of structured products based on data warehouse and a data analysis method of non-structured products based on Hadoop. By means of the former method, firstly product data was filtered, tranformed and loaded into the warehouse, then the required data cube was extracted, lastly the structured product data was analyzed with the analysis tools of data warehouse. By means of the latter method, the product data firstly was loaded into the distributed file system,and the non-structured massive PLM product data was analyzed by the data mining algorithm,which was programmed by JAVA language based on MapReduce. By applying the methods mentioned above to massive PLM product data analysis, it shows that these methods hava a higher efficiency.

The joint of 2219-T6 aluminum alloy plate was obtained by friction stir welding, and the microstructures and mechanical properties of the joint were investigated. The causes of the weakened joint strength in friction stir welding were analyzed and summarized correspondingly. The tensile properties show that the transverse tensile strength of the joint can reach about 70% of the base metal. Through the heat treatment of recrystallization with high temperature and at short time, the joint can restore the ductility and eliminate the softening, which will improve the performance in mechanical intensity of the joint.

The joint of 2219-T6 aluminum alloy plate was obtained by friction stir welding, and the microstructures and mechanical properties of the joint were investigated. The causes of the weakened joint strength in friction stir welding were analyzed and summarized correspondingly. The tensile properties show that the transverse tensile strength of the joint can reach about 70% of the base metal and the elongation can reach about 7%. The main reason of the weakened strength is due to the plastic damage of metal, followed by the defects generated in the nugget zone and the growth of θ phase in the heat affected zone.

According to lower efficiency, non-uniform distribution and metering difficulty in grouting, this paper describes the development of monitor system for automatic grouting of metamorphic concrete. Based on PLC and HMI, it uses the knowledge of signal acquisition and hydraulic control technology. This system calculates the rotation division angle to measure the amount of grouting through the hall-switch installed on the rotor of slurry pump. The PLC will realize signal acquisition, slurry metering, and effectively control of the slurry pump by solenoid valves and hydraulic motor. In addition, the HMI provides the functions such as parameters setting, operation controlling and data displaying.

In order to improve the automation level of the metamorphic concrete grouting machine, an automatic positioning control system was developed based on the knowledge of signal acquisition and hydraulic control technology with PLC and HMI. Angle sensors installed on the arms of the grouting machine and the grouting working device were used in this system. Firstly, users determine the reference position according to practical needs, and use the PLC to complete information collection and respective reference positions recording. Then, before the grouting starts, PLC makes a real-time detection and compares the positions of the excavator boom, arm and the grouting working device, and controls the hydraulic cylinders of the excavator sequentially to adjust the positions through electro-hydraulic proportional velocity regulating valve and solenoid control valves. This control system can realize automatic positioning.

The gate-type steel-shuttering jumbo is key construction equipment for tunnel lining, which is usually designed for customization according to the shape and size of the tunnel. Aiming at the insufficiency of existing methods in the jumbo design, the CAD/CAE technology is introduced into the domains of the jumbo design. In this paper, the gate-type steel-shuttering jumbo for spillway lining in Xiluodu hydropower station is designed, and virtual assembly is established based on three-dimensional digital model using Pro/E software. The stress and strain of the jumbo under different working conditions are analyzed by ANSYS. The result of finite element analysis can be regarded as the basis of structure design and optimization of the jumbo, and can be used to verify the design feasibility at the same time.

Based on cylindrical diffusion theory and characteristics of enriched vibrated Roller Compacted Concrete (RCC), a model of grout permeation was established. According to this model and generalized Darcy’s law, a formula was deduced, which shows the relationship among diffusion radius of grout, grouting pressure, radius of grouting pipe, construction time, viscosity of grout, permeability coefficient of RCC, porosity of RCC and rheological index of grout, computing steps by this formula were presented, and results of computing grout diffusion radius for an equipment of grouting in Roller Compacted Concrete was given, which was developed for construction of RCC dam at Tingzikou hydraulic power station.

As the key components of large-scale hydraulic radial gate, hinge system play an important role in supporting the gate and sustaining loads. They must satisfy the requirements of intensity, rigidity and supporting stability. Due to the complicated working conditions of the gate, it is difficult to calculate stress and strain of the hinge system based on traditional design method. In this paper, taking the radial gate in Silin hydropower station as an example, finite element technology is introduced into the analysis of the hinge system. The approach of this work includes steps of (1) obtaining the maximum load of the hinge system by analyzing and comparing different working conditions of the gate, (2) modeling the hinge system by meshing, loading and boundary constraints, and (3) computing stress and strain of its major components under the most dangerous condition. The results verify design feasibility and structural reliability of the hinge system.

Universal-rod steel-shuttering jumbo (URSSJ), as a key construction equipment for tailrace tunnel lining of underground plant in Pubugou hydropower station, has a good reusability in structure but must satisfy the requirements of intensity, rigidity and supporting stability. Due to complicated working conditions of the URSSJ, it is difficult to calculate stress and strain of the URSSJ based on traditional design method. In this paper, finite element technology is introduced into the analysis of the URSSJ. The approach of this work includes steps of (1) analyzing the structure, working conditions and load characteristics of the URSSJ, (2) modeling the hinge system by meshing, loading and boundary constraints, and (3) computing stress and strain of its major components under the most dangerous condition. The results verify design feasibility and structural reliability of the URSSJ.

Based on AMESim，a method of dynamic characteristics analysis and optimization for hydraulic system of a self-propelled steel bridge (SPSB) is presented. The approach of this work includes steps of (1) modeling the hydraulic system by defining components and their parameters according to working conditions; (2) evaluating control modes of the system, testing performance of components and analyzing main factors causing load-impacted and movement-unsynchronized of cylinders in the system by repeated changing and running of the model; and (3) improving the system. The results of this research show that sudden change of piston-rod movement and fluid pressure in hydraulic cylinders could lead to larger load-impacted of the system, and fluid pressure loss and load change of hydraulic cylinders would greatly effect on stability and synchronization of the system; but accumulators installed in the circuits can effectively decrease load impact and enhance movement steady of cylinders, and proportional valves used to control the circuits can obviously improve synchronization performance of cylinders.

Secure boot is one important way to ensure the security of system for the terminal computing platform. The existing solutions for platform secure boot are based on verification by matching the reference measurements with the runtime measurements. These solutions are complex and inefficient. Based on the existing secure boot scheme, a secure boot model based on trusted personal computer (PC) is designed. Through the use of the existing trusted computing technology, a seal-based secure boot scheme for trusted computing platform is proposed in this paper. In this scheme, it is not necessary to generate the certificates on components of the reference measurements; it is also not necessary for verification proxy to verify the integrity of the runtime measurements. At the same time, the security of platform system is effectively guaranteed during booting.

Structure design of a product under complex loads not only must meet the conditions of its strength and stiffness, but also must consider the requirements of its fatigue life. Due to the lack of historical data of actual loads and stress, it is usually difficult to predict the fatigue life of product structure in life-customized design. Taking self-propelled steel bridge as an example, which is used for spoil transportation of tunnel construction in the Beijing-Shanghai high-speed railway projects, this paper presents a method of fatigue analysis for product structure for life-customized design. The approach of this work includes steps of (1) simulating actual work and load conditions of the bridge based on finite-element (FE) method, and determining risk components of the bridge, (2) analyzing the stress time history of dangerous components of the bridge, and drawing out the stress spectrum to solve the bottleneck problem of fatigue life calculation in the bridge design, (3) correcting the material S-N curves and predicting the fatigue life of the bridge based on Miner linear cumulative damage theory. The results of this research will facilitate implementation of life-customized design, thus meet the requirements of expected life of the bridge, and also improve the reliability and security of the bridge in engineering application.

P-selectin in platelets and endothelial cells mediates adhesive interactions between platelet, leukocyte and endothelium to form thrombi. The purpose of the present study was to investigate the plasma level of soluble P-selectin (sP-selectin) in patients with coronary heart disease and the relationship between sP-selectin and plasma concentration of lipoprotein(a) [Lp(a)]. Levels of sP-selectin and Lp(a) were determined by enzyme-linked immunoabsorbent assay on plasma taken from patients with acute myocardial infarction (AMI), old myocardial infarction (OMI), unstable angina (UA), stable angina (SA) and the controls. In patients with AMI and UA, sP-selectin levels (79.62±3.82 ng/ml, 43.75±2.97 ng/ml, respectively) were significantly higher ( P r =−0.315 P

Neomycin resistance gene (neo(R)) flanked by 5' and 3' regions of fibroin H-chain gene of silkworm (Bombyx mori.L.) was transferred into eggs of silkworm by gene gun in the early period of fertilization. The larvae were fed with an artificial diet containing neomycin in early 24 hours post transfettion, and some of them survived. The neo(R) encoding sequence in G(2) generation derived from the survivals was detected by Southern blotting. The results indicated that neo(R) could be used as a selective marker for studies on transgenic silkworm.

A gene unit, which encoded fibroin-like peptide, was synthesized and constructed. The unit was multimerized to about 2 400 bp using BamHI and BglII at each end of the unit, then was fused with gfp reporter gene. The fusion gene, flanked by the 5'and 3'sequence of the fibroin heavy chain gene of silkworm Bombyx mori, was transferred into the eggs of silkworm by electroporation. After the silkworms developed and spinned silk, 73 out of about 5 400 cocoons were brighter than normal ones under UV light. The protein extracted from the brighter cocoon could react with the GFP polyclonal antibodies. Genomic DNA from these silkworms and their progenies were analyzed. The integration of gfp gene into genomic DNA of silkworm and the occurrence of expected homologous recombination event had been proved by Southern hybridization. It was shown that gfp-fibroin like fusion gene had integrated into the genomic DNA of silkworm by homologous recombination and the phenotype of "brighter cocoon" could be used to select transgenic silkworms.

Background Visceral leishmaniasis (VL) is endemic in western China, and becoming an important public health concern. Infected dogs are the main reservoir for Leishmania infantum, and a potential sentinel for human VL in endemic areas. In the present study we investigated the prevalence of Leishmania DNA in dogs from Wenchuan, Heishui and Jiuzhaigou County in Sichuan Province, southwestern China, which are important endemic areas of zoonotic VL, detected by real time PCR. The results will help to design control strategies against visceral leishmaniasis in dogs and humans. Results The overall prevalence of Leishmania DNA in dogs was 24.8% (78/314) in Sichuan Province, with the positive rate of 23.5% (23/98) in Wenchuan County, 28.2% (20/71) in Heishui County, and 24.1% (35/145) in Jiuzhaigou County, and no significant difference was observed among the three counties (P > 0.05). The dogs were further allocated to different groups based on sexes, ages and external clinical symptoms. The logistic regression analysis revealed that a higher prevalence was found in older and external symptomatic dogs, compared to that of younger and asymptomatic dogs (P < 0.05). Conclusions The results revealed that L. infantum infection in dogs is widespread in Sichuan Province, southwestern China, which has a public health significance, due to its contribution to the transmission of the infection to humans by sandflies. It is necessary to take measures, including treatment or eradication of infected dogs, to control canine leishmaniasis, which could be helpful to reduce human VL in this area.