bluuebunny/crossref_metadata_2025 huggingface dataset:
Sustaining Healthcare Through Waste Elimination
Authors: Falan Sharie L. , Han Bernard , Zoeller Linda H. , Tarn J. Michael , Roach Donna M.
Published: November 2011

The growth in U.S. national health expenditures (NHE) has continuously outpaced its Gross Domestic Products (GDP) growth since 1997 and this trend will continue with a 2.1% annual gap for the next decade (RAND, 2010). This nonstop healthcare cost increase make healthcare one of the most urgent issues in USA. Concurred by this study, the key factor that drives up the healthcare costs is waste. In this paper, a taxonomy on the root causes of healthcare waste is developed with a corroboration on why healthcare waste could be eliminated through effective use of health information technology (HIT). Furthermore, real world cases are used to highlight the research findings that waste can be avoided by: (a) recognizing the precursor of each potential waste, (b) examining business processes using defined detection criteria, and (c) implementing HIT systems that support efficient information sharing among all healthcare stakeholders. Finally, recommendations for implementing IT enabled healthcare management systems are presented.
A Heuristic Method for Learning Path Sequencing for Intelligent Tutoring System (ITS) in E-learning
Authors: Al-Radaei Sami A. M. , Mishra R. B.
Published: November 2011

Course sequencing is one of the vital aspects in an Intelligent Tutoring System (ITS) for e-learning to generate the dynamic and individual learning path for each learner. Many researchers used different methods like Genetic Algorithm, Artificial Neural Network, and TF-IDF (Term Frequency- Inverse Document Frequency) in E-leaning systems to find the adaptive course sequencing by obtaining the relation between the courseware. In this paper, heuristic semantic values are assigned to the keywords in the courseware based on the importance of the keyword. These values are used to find the relationship between courseware based on the different semantic values in them. The dynamic learning path sequencing is then generated. A comparison is made in two other important methods of course sequencing using TF-IDF and Vector Space Model (VSM) respectively, the method produces more or less same sequencing path in comparison to the two other methods. This method has been implemented using Eclipse IDE for java programming, MySQL as database, and Tomcat as web server.
Simulation on Knowledge Transfer Processes from the Perspectives of Individual’s Mentality and Behavior
Authors: Wu Jiangning , Liu Na , Xuan Zhaoguo
Published: November 2011

Knowledge transferring between people within an organization leads to varied results due to individuals’ distinctive mentality and behavior. In this study, mental and behavioral factors, such as the prestige and reputation of individual and the movement for people within the organization, are introduced to examine their impact on knowledge transferring between individuals. A conceptual model is proposed which involves two actors in the process of knowledge transfer, knowledge sender and knowledge recipient, their corresponding disseminative capacity and absorptive capacity, as well as mental and behavioral factors. Accordingly, a network model is constructed in which nodes act as the knowledge senders or recipients. The process of knowledge transfer on the network is inspected from two mental aspects—the prestige and reputation of individuals. The degree of impact of the factors on knowledge disseminative will or knowledge absorptive will of actors is measured. A personnel movement mechanism is also introduced to simulate the dynamic processes of knowledge transfer within the organization. The simulation results show that the positive mental factors for individuals can promote the disseminative capacity of knowledge senders, accelerate the processes of knowledge transfer, and improve the knowledge stock of the organization.
Optimal Thresholds of an Infinite Buffer Discrete-Time Two-Server System with Triadic Policy
Authors: Goswami Veena , Mund G. B.
Published: November 2011

This paper analyzes a discrete-time infinite-buffer Geo/Geo/2 queue, in which the number of servers can be adjusted depending on the number of customers in the system one at a time at arrival or at service completion epoch. Analytical closed-form solutions of the infinite-buffer Geo/Geo/2 queueing system operating under the triadic (0, Q N, M) policy are derived. The total expected cost function is developed to obtain the optimal operating (0, Q N, M) policy and the optimal service rate at minimum cost using direct search method. Some performance measures and sensitivity analysis have been presented.
Security Evaluation of Service-Oriented Systems Using the SiSOA Method
Authors: Jung Christian , Rudolph Manuel , Schwarz Reinhard
Published: November 2011

The Service-Oriented Architecture paradigm (SOA) is commonly applied for the implementation of complex, distributed business processes. The service-oriented approach promises higher flexibility, interoperability and reusability of the IT infrastructure. However, evaluating the quality attribute security of such complex SOA configurations is not sufficiently mastered yet. To tackle this complex problem, the authors developed a method for evaluating the security of existing service-oriented systems on the architectural level. The method is based on recovering security-relevant facts about the system by using reverse engineering techniques and subsequently providing automated support for further interactive security analysis at the structural level. By using generic, system-independent indicators and a knowledge base, the method is not limited to a specific programming language or technology. Therefore, the method can be applied to various systems and adapt it to specific evaluation needs. The paper describes the general structure of the method, the knowledge base, and presents an instantiation aligned to the Service Component Architecture (SCA) specification.
Peer-to-Peer Service Quality in Virtual Communities
Authors: Valtakoski Aku , Peltonen Juhana , Laine Mikko O. J.
Published: November 2011

Virtual communities are an increasingly popular way to conduct business over the Internet. However, from the service provider’s point of view they pose special challenges. In particular, unless the provider itself engages in content or service provision, the service relies entirely on its members for provision of services. The members should thus be seen as resources for service provision. This type of networked service production system implies challenges in terms of service quality management and, subsequently, value creation for community members. This paper explores these issues by revisiting service marketing and service operations literature on service quality. Analysis of the literature indicates that firms facilitating virtual communities need to ensure the quality of their service by not only ensuring technical quality but also by nurturing the social aspects of the community that have an impact on the willingness of community members to provide service to each other.
Optimization of Xylanase Production by Trichoderma reesei JL-1 Using Response Surface Methodology and the Enzymatic Properties
Authors: Liu Ming Qi , Dai Xian Jun , Liu Guang Fu , Guan Rong Fa
Published: November 2011

The production of xylanase (TrxA) byTrichoderma reeseiJL-1 in solid-state fermentation (SSF) was optimized by response surface methodology (RSM). Results revealed that factors of concentration of added ammonium sulfate, and moisture content had significant effect on the TrxA production (P<0.05). The maximum xylanase activity (485.0 U/g U/g dry fermentation product) was obtained at 2.9% the ammonium sulfate by employing wheat bran as the solid substrate, 61.6% moisture content and 59.5-h fermentation, which was close to the predicted one, and was 1.8 times as high as that of the basic medium. The optimum temperature and pH for TrXA activity were 45°C and pH 5.0, respectively. Over 90% of xylanase activity was retained after treatment of the enzyme by preincubation over a pH range of 3.0-5.0 for 1 h at 25°C. TrxA exhibitedKmandVmaxvalues of 1.458mg/mL and 25.316 μmol/min/ml, respectively. In the presences of metal ions such as Mn2+the activity of the enzyme increased. Whereas strong inhibition of the enzyme activity was observed in the presences of Fe3+and Ca2+.
P2P Incentive Mechanism Based on Static Game of Incomplete Information
Authors: Liu Xi , Liu Jun , Zhu Chun Yan
Published: November 2011

P2P network is autonomous of sharing file quickly and easily. In recent years, a large number of free-riding nodes and malicious nodes emerge in P2P network, which can’t provide services and have malicious damage to the network system, the result is significant declines of system performance and user satisfaction. In order to solve the problems, a P2P incentive mechanism based on static game of incomplete information is proposed in this paper. The new proposed mechanism has been analyzed and simulated with a series of tests. Experimental results show that the proposed P2P incentive mechanism can solve problem simply and effectively.
Energy-Based Inverted Equilibrium of the Axially Symmetric 3D Pendulum
Authors: Lv Wen Jun , Ge Xin Sheng
Published: November 2011

In this paper, we study the attitude control problems based on model of the 3D axially symmetric rigid pendulum. Three degrees of freedom pendulum (3D pendulum) is a rigid body supported by a frictionless pivot. According to relative position of the center of mass and the fixed pivot without friction, the 3D rigid pendulum can be divided into two balanced attitudes, Hanging equilibrium and inverted equilibrium. When the 3D rigid pendulum in axis symmetric case, the axis of symmetry is equivalent to axis of inertia of rigid body, and angular velocity around the axis of symmetry is constant that not equal to zero, as a result, the 3D rigid pendulum equal to the axisymmetric rigid pendulum. According to the motion attitude of the axially symmetric 3D pendulum, this article proposes a control method based on passivity, By analyzing the dynamic characteristics, and demonstrate the dynamic characteristics to meet the passive condition. Firstly, we use the passivity theory, from total energy of the system, to research the equilibrium stability of the axially symmetric 3D pendulum in the inverted position. Secondly, to utilize the passivity theory and the Lyapunov function that we proposed to deduce the control law based on the energy method, so that the axially symmetric 3D pendulum to reach asymptotically stable in equilibrium position, and the simulation results verify the availability of the method.
Analysis of Dynamic Load Level of High-Speed Heavy Vehicle Imposed on Uneven Pavement
Authors: Guo Guo He , Bai Yu Feng , Wang Tao
Published: November 2011

Based on the significant destructive effect of heavy vehicle on uneven roads, two simplified models of pavement unevenness and vehicle dynamic load were established in accordance with D'A lembert principle, and Matlab software was used to analyze the changing law of dynamic load under the conditions of different road unevenness, vehicle speed and load. The results show that vehicles running on uneven road may produce more cumulative damages than static load, and DLC (dynamic load coefficient) changes in wide range, maximum up to 2.0 or more; the effect of speed and load on dynamic load is complex, and due to multi-factor interaction, DLC doesn’t consistently increase or decrease with speed and load increasing. Although the dynamic load level caused by high-speed heavy vehicle is not necessarily too high, its impact on the road can not be ignored.
Folding Umbrella Framework Destruction Force Analysis Based on Virtual Prototype
Authors: Song Qiu Hong , Ma Yong Mei , Xu Zhe , Jia Nan , Zheng Yan Ping , Yuan Jun Ting
Published: November 2011

Failure analysis is important for the safety design of the folding umbrella. The failure point is found on certain location after large amount of samples statistics. In order to verify this problem, apply SolidWorks to finish the umbrella framework model, import the model into ADAMS. Then the experiment is conducted, the push force on the umbrella piston which adds to the mechanical model is measured through Gravity Sensor. The dynamic simulation of umbrella framework is discussed by using ADAMS. The simulation result shows the failure point we found is accurate. Since the destructive force on umbrella is diversity and uncertainty, further studies are necessary for this subject.
Methods Determining the Weights of Characteristics in Mechanical Products Design on Case-Base Reasoning
Authors: Ji Ai Min , Zhu Kun , Huang Quan Sheng
Published: November 2011

In Case-Based Reasoning (CBR), the determination of the weights of case characteristics is the base of the accurate case match, even influences the CBR execution. The current methods of determining the weights of case characteristics include subjective and objective weighting method but, some defects exist in them. In order to decrease subjectivity and increase objectivity of weight determining, the paper presented a new kind of combination weighting method that is the combination of the Analytic Hierarchy Process (AHP) with roughness set theory. The weighting process about AHP, roughness set theory, and combination method was described in detail respectively. An example was given to verify the effectiveness and accuracy of the combination weighting method.
Modeling and Analysis of the Supporting Force of Water Strider’s Legs
Authors: Wang Qing Cheng , Yang Xiao Dong , Shang Guang Rui , Yang Zhuo Juan , Cao Guo Hua , Xu Hong Ji
Published: November 2011

In this paper, the microstructure of the water strider’s legs was observed, the lengths, diameters of the water strider’s legs were measured by the instruments such as scanning electron microscope . The supporting force model of water strider’s legs was established, the factors associated with the supporting force were analyzed. The critical conditions in which water strider’s legs do not pierce the water surface were discussed. the maximum supporting force of water strider’s single hind leg was calculated according to the supporting force model of water strider’s legs, the calculated value is 3399.13×10-6N, which is about 17 times of its body weight.
The Solution of the Structural Reliability Index Based on SAPSO
Authors: Liu Ke Tong , Tang Ai Ping
Published: November 2011

In view of the shortcoming of the existing structural reliability calculation method, this paper establishes optimization model of the structural reliability index from the geometric meaning of the structural reliability index. Then, the authors propose a method based on improved particle swarm optimization algorithm for solving the reliability method. Particle swarm algorithm is easy to fall into local optimum. So, the authors construct simulated annealing particle swarm algorithm which has the strong local search ability .simulated annealing particle swarm algorithm is a global optimization algorithm. Using it to solve the reliability index can avoid doing partial derivatives to the structural performance function and the deficiency of traditional method is effectively overcomed which is easily being trapped in local optima. Therefore, it is a very effective method to solving the structural reliability index of the complex structure. In the end, some examples demonstrate the validity of this method.
Numerical Simulation and Analysis of Motion Process of Incompact Soil along Slope
Authors: Ji Xian Jun , Ou Guo Qiang
Published: November 2011

Simulating motion process of incompact soil. Monitoring evolution process of average contact force and unbalance force between particles during moving; Recording microscopic parameters and its changing processes, incliding spatial locations, translational rate and rotation rate of specific particle during the moving. Simulation results properly reproduced the whole process of it along slope, which include the starting, moving, piling up. Simulation results indicate that: Process of its motion manifest the macro space position changes, as well as, are the change process about contact stress, unbalance force within the inter particle and single particle movement mechanics etc. Size of average contact force reflects close degree between particles, fluctuation extent of microscopic parameter and levels of interaction between particles. Microscopic parameters of movement process can be used in the theoretic modeling analysis of complex movement of the incompact soil.
Model Test Investigation on a J-Lay System Designed for Deepwater Pipeline Installation in South China Sea
Authors: Li Ming Jie , Duan Meng Lan , Yu Fang Fang , Zhang Hong Huan , Ren Xiao Yao , Li Cai Xia
Published: November 2011

A J-lay crane barge named Double-8000, the two cranes of which have the lifting capacity of up to 8000t, is about to be constructed by Offshore Oil Engineering Co., Ltd. (COOEC) in order to meet the requirements of oil and gas development in South China Sea. This paper presents the overall structure design of the J-lay system and corresponding method for strength calculation. The hardware and software for the J-lay control system are also developed. The model test on such a designed J-lay system along with its control system is investigated by applying the similarity theory and the hybrid model test method. A specially designed platform simulating the motion of the crane barge in 6 degree-of-freedom (6-DOF) in different sea conditions is used for the model testing in order to get the results of the influence of the crane motion on the performance of the J-lay system. The model tests verify the functionality and safety performance of the system. The results show that the test data are in good agreement with the numerical simulation. It can be seen that the J-lay system can meet the challenging requirements of Double-8000 for pipeline laying in waters deep to 3000m in South China Sea.
Algorithm Establishment with Model Experiment for Continuous-Wave Functional Near-Infrared Spectroscopy
Authors: Li Ting , Zhang Zhi Li , Zheng Yi
Published: November 2011

Although functional near-infrared spectroscopy (fNIRS) has been developing as a useful tool for monitoring functional brain activity since the early 1990s, the quantification of hemoglobin concentration changes is still controversial and there are few detailed reports especially for continuous-wave (CW) instruments. By means of a two-layer model experiment mimicking hemodynamic changes in brain and mathematical analysis based on the modified Beer-Lambert law, we established an algorithm for a CW functional near-infrared spectroscopy (CW-fNIRS). The accuracy of this algorithm was validated both in comparison with direct measurements on brain tissue model and in vivo measurement upon human valsalva maneuver. This described method can also be utilized for other CW-fNIRS instruments to establish measuring algorithm.
Experimental Study on Vibration Absorption Characteristic of Non-Obstructive Particle Damping Beam
Authors: Wang Wei , Li Yu Yan
Published: November 2011

Non-obstructive particle damping (NOPD) is developing in combination with particle damping technique, impact damping technique and material science. NOPD technology has good damping characteristic and nicer effect on vibration absorption. In the paper experiments of vibration absorption characteristic for beam applying NOPD are done and some conclusions are obtained, which affords important reference for engineering application of NOPD technique.
The Design of the Multi Fitness Function Office Chair
Authors: Ren Jian Ping , Ye Yu Gang
Published: November 2011

This paper proposed a design of the office chair with multi fitness function (multi-functional office chair for short) which can mainly achieved comfortably office; adjust the reline angle, doing fitness activities, such as stretched movement, kicking motion, sit-ups and so on. It not only satisfies the needs of people's daily work, rest and fitness exercise, but also meets the design requirements of ergonomics.
Residual Stress Effects on Crack Growth in Nugget of Al-Li Alloy 2195-T8 Friction Stir Welded Joints
Authors: Ma Yu E , Wang Li Ning , Liu Bao Qi
Published: November 2011

In this work, Compact-Tension (C(T)) specimens with transverse welds in the sample centre were designed. The residual stress distributions were measured parallel and perpendicular to the weld nugget. Fatigue crack growth (FCG) rates were measured in the lab air. It is shown that compressive residual stresses around notch have significant effect on FCG rates and the effect deceases with crack growing. FCG rate is lower in the nugget than in parent material. Effects of residual stress were studied with crack growing. The lower crack growth rate in nugget is believed to be linked in part to compressive residual stress, but also in part to a microstructure effect present when crack grows in the recrystallized nugget.
A Study on the Aerodynamic Safety of Skirt Board Structure on Maglev Train
Authors: Liu Zhi Qiang , Ma Wei Hua , Luo Shi Hui
Published: November 2011

Utilizing CFD, the influences of skirt board structure on high speed maglev train's aerodynamic resistance and the stability under crosswind are studied. Studies have been conducted on the aerodynamic of skirt boards which located on different positions. Simulation analyses are finished with maglev train running at speed of 350km/h for both with and without crosswind. Study results show that, some skirt boards are likely to be pulled apart, further, lower the safety limit speed.
The Analysis of Matching Detection Based on Dielectrophoresis Effects
Authors: Han Lei , Yang Guo Qiang
Published: November 2011

When the effects of dielectrophoresis (DEP) is applied in the detector design, it can be used to detect and locate multi targets.In this paper, the DEP force of neutral objects in the non-uniform electric field is firstly derived.According to analyze the force of insulators in the non-uniform electric field,we can conclude that the mechanical expression of matching detection is DEP force.Then the parameters of DEP force are analyzed and simulated, and it is of great significance to design detector and choose parameters for detector.Finally, through the analysis of the principle of matching detection, the article gives the technology implementation approach of this principle.The results show that this detection method can be used to detect the targets which has the same dielectric material with the detected objects, and it has a strong anti-interference ability.
Preparation and Characterization of Mno.5Zno.5Fe2O4 @Au Composite Nanoparticles and its Anti-Tumor Effect on Glioma Cells
Authors: Li Yun Tao , Liu Jing , Wang Li , Zhang Jia , Wang Zi Yu , Zhong Yue Jiao , Zhang Dong Sheng , Gao Zhi Qiang
Published: November 2011

To explore the preparation method and characters of a new gold nanoshells on maganese-zinc ferrite (Mno.5Zno.5Fe2O4@Au) composite nanoparticles. Mno.5Zno.5Fe2O4@Au nanoparticles with core/shell structure were synthesized by reduction of Au3+ with trisodium citrate in the presence of Mno.5Zno.5Fe2O4 magnetic nanoparticles (MZF-NPs) prepared by improved co-preciption with the character of superparamagnetism and detected by transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), energy dispersive spectrometry (EDS) and Marven laser particle size analyzer.Thermodynamic test was used to observe temperature change of various doses of Mno.5Zno.5Fe2O4@Au nanoparticles. The cytotoxicity of the Mno.5Zno.5Fe2O4@Au composite nanoparticles in vitro was tested by the MTT assay. The therapeutic effect of Mno.5Zno.5Fe2O4@Au composite nanoparticles combined with magnetic fluid hyperthermia (MFH) on human glioma cells were evaluated in vitro by an MTT assay.The results indicated that the Mno.5Zno.5Fe2O4@Au composite nanoparticles were prepared successfully. The core/shell particles were spherical with exact average diameter of them was 66.9nm.EDS showed each Mno.5Zno.5Fe2O4@Au nanoparticle contained Mn, Zn, Fe, O and Au elements, and this proved Au had successfully attached to Mn0.5Zn0.5Fe2O4.The result of thermodynamic test showed that Mno.5Zno.5Fe2O4@Au composite nanoparticles could serve as a heating source under alternating magnetic field (AMF) exposure leading to reach their steady temperature (40-45°C). Moreover, Mno.5Zno.5Fe2O4@Au composite nanoparticles didn’t show cytotoxicity in vitro. The therapeutic result reveals that Mno.5Zno.5Fe2O4@Au composite nanoparticles can significantly inhibit the growth of glioma cells.The conclusion was that the self-prepared Mno.5Zno.5Fe2O4@Au composite nanoparticles had strong magnetic responsiveness and good power absorption capabilities in the high frequency AMF,then they could suggested to be useful for glioma hyperthemia. Mno.5Zno.5Fe2O4 @Au composite nanoparticles can not only be directed to tumor region in a given magnetic field more exactly but also produce marked thermotherapy.
Studies on Optimum Conditions of Synthesizing Theaflavins by Using Bio-Enzyme Method
Authors: Fang Wan Ping , Wang Li Pu , Yu Jun , Yue Peng Xiang , Jiang Xin , Feng Wei Ying , Chenzhou Yi Qi , Li Xing Hui
Published: November 2011

Green tea powder and polyphenol oxidase extracted from eggplant has been used to explore the optimum condition for theaflavins synthesis under single factor and orthogonal experimental design. The results showed that pH value had significant effect on theaflavins synthesis. The optimum reaction condition was, under the temperature of 25°C, the system pH value 4.5, substrates concentration 2.5 g/L, and 35 mL crude enzyme with 196 U, reaction time 40 min, then the total content of theaflavins reached to 7.45 mg.
Microinjection Molding of Polymer Micromixers for Biomedical Application
Authors: Yang Can , Yin Xiao Hong , Li Lei , Castro Jose M. , Yi Allen Y.
Published: November 2011

In recent years, microinjection molding has been widely used for fabricating polymer components due to its cost effectiveness and mass-production capability. In this work, the fabrication process of a polymer micromixer was presented. The micromixer was designed in such a way that the fabrication process could benefit from the process capabilities of ultraprecision micromachining and microinjection molding. An amorphous polymer material polymethylmethacrylate was used to make the micromixers. Moreover, in order to investigate the effects of processing parameters on replication quality of the micromixer, four important factors in microinjection molding, namely the melt temperature, injection velocity, packing pressure and packing time were selected as variables. The experimental results showed that the melt temperature was the most important factor influencing the replication, followed by the injection velocity. However, the packing pressure and packing time had no obvious influence on the replication of the micromixer.
Clinical Results of Retaining Denatured Dermis with Autograft Skin
Authors: Zhao Yao Hua , Yang Hui Guang , Deng Hai Tao , Xu Li Hong , Zou Da Zhong , Shen Yao Ming , Huang Wei Qi , Yuan Dong Liang
Published: November 2011

Objective: To explore the feasibility and clinical value to keep the denatured dermis in the deep II degree burns. Methods: With the consent of the 41 patients, their burn wounds were divided into two groups, one group is called the observation group, and the other is called the control group. Comparison was made in the same body. Apply retaining denatured dermis plus autograft skin in the observation group and scab removing plus autograft skin in the control group, individually. Then compare the following factors of the two groups: blood loss amount, 14th day wound healing rate, and the color B-measurement of the thickness from the skin surface to fascia thickness. Results: The blood loss was 10.2 ± 2.3 ml in the observation group, 39.2 ± 6.1 ml in the control group. t = - 22.3, P = 0.000; 14d wound healing rate was 75.6% (31/41) in the observation group, and 87.8% (36/41) in the control group. 2= 0.581; P > 0.05. The thickness of skin and subcutaneous tissue was measured to be 1.2 ± 0.5cm in the observation group, and 0.8 ± 0.3cm in the control group, t = 19.4, P = 0.000. Conclusions Retain denatured dermis and implant autograft skin surgery can reduce the intensity of operation, it can also benefit the skin and soft tissue reconstruction. Thus, it is one of the most effective surgical methods in the treatment of deep II degree burns.
MRI and MRA Diagnosis of Intracranial Aneurysms
Authors: Ji Guang Qian , Wei Jun , Tian Yu
Published: November 2011

With the development of modern medical imaging technology, computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), digital subtraction angiography (DSA) and other ways widely used, more and more intracranial aneurysms were diagnosed. In the imaging methods described above, MRI is a non-invasive diagnostic method for intracranial aneurysm which shows in detail the aneurysm and its relationship to the brain, and it has become first-line imaging techniques in assessment of the patient with suspected intracranial aneurysm. MRA can show the arteries and veins of the brain as well as the aneurysm. Nowadays, MRI and MRA are extensively used in the diagnosis of intracranial aneurysms, intracranial aneurysms after treatment and intracranial aneurysms inflammation. This review describes the advantages of MRI and MRA for diagnosis and describes diagnostic pitfalls.
Numerical Simulations of the Non-Newtonian Blood Blow in Human Abdominal Artery Based on Reverse Engineering
Authors: YANG Jin You , Hong Yang
Published: November 2011

The method that combined the reverse engineering based on CT medical images and computational fluid dynamics (CFD) was used to perform simulation the Non-Newtonian blood fluid flow in human abdominal artery, then analyzed the hemodynamic condition about the bifurcation of human abdominal artery. A Non-Newtonian blood model (the Generalised Power Law) was used to study the hemodynamic parameters during entire cardiac cycle. Calculated results for the Non-Newtonian blood flow show us the methods performed in this study is suitable for numerical simulating the blood flow in human artery and investigating the relation between hemodynamic factors and vascular disease.
Application of Gray-Scale Texture Feature in the Diagnosis of Pulmonary Nodules
Authors: Shi Chang Zheng , Zhao Qian , Luo Liang Ping
Published: November 2011

In this paper, we have proposed a new way to detect lung nodules with image texture features. 104 cases of lung nodules, including 31 benign cases and 73 malignant cases, are collected, and the gray-scale correlation and texture heterogeneity are computed through CT imagings for all patients. We find that the gray correlation parameters are different between benign and malignant nodules. The heterogeneity parameters in malignant nodules are higher than that in benign noduals. The gray-scale texture correlation and heterogeneity parameters have diagnostic value in differentiating benign and malignant lung nodules. This study is an exploring study, which still needs further research.
Bio-Inspired Fabrication of Polymer Composite Scaffolds with Chitosan Network inside the Pore Channels
Authors: Li Bo , Li Li Hua , Zhou Chang Ren
Published: November 2011

Solid freeform fabrication, known as rapid prototyping (RP) technology allows in designing the scaffold with pre-defined and controlled external and internal architecture.In this study we produce scaffolds with network of chitosan fibrils that mimic the extracellular matrix produced by the cells. These network scaffolds also consisting of nanoparticles of hydroxyapatite (HA) for stabilisation of scaffolds are characterised by environmental scanning electron microscopy and mechanical properties. ESEM showed that the scaffolds possess macropore (300µm), micropore and fibre network structure. The compressive strength and elastic modulus (E) for the scaffolds are 0.54± 0.02 MPa and 6.13± 0.60 MPa, respectively, which are increasing obviously. The biocompatibility of the woodpile-network scaffolds was investigated with osteoblastic cells. The result showed the distribution and proliferation of osteoblast orients along the chtosan fibre network, preferentially. After 4 weeks of culture, macropore channels are covered by cells in large part,while the areas without chitosan fibre network are covered rarely. The properties of these scaffolds indicate that they can be used for bone tissue engineering applications.
Surface Modified Polylactic Acid Microspheres Reinforced Calcium Alginate Hydrogels
Authors: Li Lei , Lu Lu , Zhou Chang Ren , Xu Zuo Cong
Published: November 2011

Calcium alginate hydrogels, offering cells with three dimensional growing environments similar to that experienced in vivo, is an appealing materials utilized as scaffolds in tissue engineering. However, how to improve its mechanical property and expand its use is becoming an urgent topic that draws great attention. In this paper, we introduced polylactic acid (PLLA) microspheres, treated by surface aminolysis, into calcium alginate hydrogels that was fabricated by the methodology of in-situ release and transformation. The surface aminolysis modification improved the hydrophilicity of PLLA microspheres, which increased the integration between PLLA microspheres and calcium alginate hydrogels. Within the composite hydrogels, PLLA microspheres can play the role of hindrance for the extension of cracks and improve its mechanical strength. Meanwhile, PLLA microspheres can also be used as hydrophobic drugs delivery vehicles to transport gene, protein, peptide and the like. In this way, with the enhancement of mechanical strength and newly given functions, the fields in which the composite hydrogels can be applied can be broadened significantly.
A Nonlinear PID Controller for Electro-Hydraulic Servo System Based on PSO Algorithm
Authors: Chen Ji Peng , Lu Bao Chun , Fan Fan , Zhu Shi Chun , Wu Jian Xin
Published: November 2011

Linear PID controller is adopted by electro-hydraulic servo system widely. The proportional, integral and derivative coefficients of a linear controller are fixed which brings the contradiction in speediness and overshoot. This paper designs a series of nonlinear functions which are used for nonlinear PID control for electro-hydraulic servo system. The proportional, integral and derivative parts of this nonlinear PID controller adjust themselves according to the error. In order to determine parameters of the nonlinear functions, PSO Algorithm and ITAE guideline are applied in the paper. Results of simulation indicate that the nonlinear PSO-PID controller using the functions proposed in this paper presents a better dynamic response than the linear PID controller.
Bearing Elevation Monitoring Instrument and its Application on Multi-Support Turbo-Generator Unit
Authors: Guo Yu Jie , Tian Yong Wei , Liu Jing Yu , Bai Yan Wu , Zhang Wen Tao
Published: November 2011

Based on the communicating vessel principle, we present a new instrument for the measurement of bearing elevation change. A number of cups are attached to the bearings. They are linked with pipes and joints together to constitute a measurement network. Special features of the instrument to make the measurement easily and reliable, such as cup design, are presented. The instrument is used to monitor and analyze the elevation change of a 1000MW turbo-generator during the vacuum setup process. We find that the influence of vacuum on the elevation of bearing located on the exhaust cylinder is large. The maximum value is 1.8mm when vacuum changes from 0KPa to 90KPa. It causes unload of bearing #5~#8 and overload of bearing #2~#4. Adjustment project is given in the last of the paper to solve rub and pad fragment fault occurred in the unit. It is verified that the elevation adjustment for such kind of fault is valuable.
Design of Automatic Assembly System of Saw Chain
Authors: Ding Ze Xin , Yuan Feng , Zhu Jun
Published: November 2011

The automatic assembly system of saw chain is designed to solve the low efficiency and poor quality of its assembly process according to the actual requirements of production. Firstly, the structure of saw chain and its automatic assembly requirements are analysed. Secondly, the different design plans on assembly process and assembly method are proposed and compared. Finally, the automatic assembly system of saw chain is designed, which is composed of feeding device and clamp positioning system. This system can not only realize the automatic assembly of saw chain, but also improve the assembly quality and prolong the using life of saw chain.
Failure Mode, Effect and Criticality Analysis of CNC Grinder
Authors: Wang Hong Jun , Sun Lei , Shi Lei
Published: November 2011

CNC grinder is considered as the key equipment of camshaft production line. Its reliability directly influences the quality of the products. This article takes an analysis of fault record of 15 sets of CNC grinders of production line, gets failure positions analysis, and then reaches data of failure modes, fault reason of CNC grinder. Comprehensive analyses of criticality for the machine are done through establishing models. Therefore, this analysis provides technical basis for repair, maintenance and update of CNC grinder of camshaft production line.
Influence of Crank Radius on the Curve Shapes for a Multi-Link High-Speed Precision Press
Authors: Lu Xin Jian , Zhu Si Hong , Ke Zun Mang , Qin Jian , Wei Shao
Published: November 2011

The parameterized dynamic simulation model for a multi-link high precision press has been established in the ADAMS software environment based on the displacement equations. The press being developed is taken as an example to study the slider’s displacement curves, velocity curves and acceleration curves under different crank radius in practice as well as the working angle curves and torque curves. With the crank radius increasing, the started punching angle comes early and the slider’s velocity and acceleration at bottom dead center (B.D.C) decreases significantly which help to improve the accuracy of B.D.C and to lower the torque consumption during stamping. Meanwhile, the increasing of working angle helps to reduce the lateral force acting on the slider, such as the torque required to overcome the inertial forces increases rapidly, the torque needed to overcome the nominal force decreases and the peak of nominal force shifts to the lower left gradually. Results of the research mentioned above are helpful to develop the multi-link high-speed press.
Investigation of Laser Parameters Influence of Direct-Part Marking Data Matrix Symbols on Aluminum Alloy
Authors: Qiu Hua Dong , Bao Wen Shuang , Lu Chang Hou
Published: November 2011

This paper studies of laser parameters for direct-part marking Data Matrix symbols on aluminum alloy by using Nd:YAG laser. Different laser parameters and the resultant can affect the barcode grade profoundly. The experiment focuses on all interval values of the vector step, inter-step time, laser Q frequency and laser Q release time. From the experiment results, the relationship between laser parameters and barcodes grade was found, and thus determined the optimal laser parameters. By analyzing the higher and the lower power density processing module SEM images and EDS data, it was found that the microstructure and micro-components of formations that created by the interaction between the laser and the aluminum alloy can affect the barcodes grade level significantly. We also found that the interaction between the laser and the aluminum alloy can be divided into four stages.
Measurement and Analysis of Cutting Force and Optimization of Cutting Parameters by High Speed Milling
Authors: Li Hu Zeng , Wang Yi , Zhu Nai Xiong , Hu Rao Bo , Zhang Chong , Wang Fang Bao
Published: November 2011

The measurement method and apparatus of cutting force by high speed milling is introduced. The high speed milling force of wrought aluminum alloy is measured and analyzed through separately examining the influences of various factors, such as cutting speed, cutting depth, milling width, feed per cutting tooth, down or up milling, cooling and lubricating. The results match with outcomes from other’s tests and the theory of metal cutting, and are close to the calculated force values, so that the test can be regarded as positive. It is pointed out that high cutting speed, little cutting depth, properly great working engagement and feed per tooth, high feed rate, down milling and efficient cooling and lubricating should be used to reduce cutting force and deformation, to improve milling accuracy and efficiency, which can be helpful to the spread applications of High Speed Machining.
Research on the Remote Monitoring and Fault Diagnosis of CNC System Based on Network
Authors: Lin Jin Zhou , Jiang Da Yong , Geng Bo , Zhang Zhong Hai
Published: November 2011

This paper aimed at NC system’s high-speed, high-accuracy, high reliability requirements. The condition monitoring, faint information extraction and fault diagnosis technology are researched of complex CNC system. Elaborated to develop a common interface and achieved the seamless interaction of CNC system and reconfigurable embedded monitoring unit basis. A machine tool monitoring diagnostic verification platform with on-machine monitoring and intelligent maintenance features of CNC system is constructed based on the internet. Integration achieved the CNC machine tools’ status remote monitoring and fault diagnosis, and detailed analysis of the key technologies for the components of the system. Through effectively integration of the computer technology, weak signal extraction technology, fault diagnosis or other technologies to enhance the automation, networking and intelligent level of the complex CNC system.
The Effect of the Restrictor Structural Parameters on the Static Properties of the Aerostatic Guide Way by Finite Element Analysis
Authors: Li Hai Peng , Ma Ping , Zhou Biao
Published: November 2011

The aerostatic guide way is one the structure of the air thrust bearings, the carrying capacity and stiffness are important static properties of aerostatic guide way. The restrictor, as the key part of the aerostatic guide way, directly affected the static characteristics. A parametric finite element model of gas film was established with APDL language based on ANSYS in this paper. Then analyzed the restrictor structural effect on the static properties of the aerostatic guide way. It found that orifice diameter and gas chamber diameter have important effect on the static properties of the aerostatic guide way.
The Online Monitoring of Surface Quality Based on Time-Frequency Spectrum Analysis of Acoustic Emission
Authors: Liu Chang , Wang Guo Feng , Qin Xu Da , Zhang Lu
Published: November 2011

There is a high requirement on the surface quality of work-pieces made of Ni-based super-alloys due to the important application in aviation and aerospace fields, so it is particularly important to implement the on-line monitoring to the surface quality of work-piece in the machining process. The acoustic emission (AE) signal has the relatively superior signal/noise ratio and sensitivity during the process of nickel alloy. Through the analysis of AE signal’s characteristic which comes from the different condition of tool wear, it is an effective mean to evaluate the tool wear condition and monitor the surface quality of work-piece due to the usage of AE during the machining process. This paper indicate that it is simple and intuitive to achieve the on-line monitoring of surface quality which based on spectrum analysis of AE signal and proposed the method of on-line monitoring of the nickel alloy surface quality under different condition of tool wear based on AE time-frequency spectrum.
Tool Wear Monitoring in Milling Processes Based on Time-Frequency Analysis of Acoustic Emission
Authors: Zhang Lu , Wang Guo Feng , Qin Xu Da , Feng Xiao Liang
Published: November 2011

Tool wear monitoring plays an important role in the automatic machining processes. Therefore, it is necessary to establish a reliable method to predict tool wear status. In this paper, features of acoustic emission (AE) extracted from time-frequency domain are integrated with force features to indicate the status of tool wear. Meanwhile, a support vector machine (SVM) model is employed to distinguish the tool wear status. The result of the classification of different tool wear status proved that features extracted from time-frequency domain can be the recognize-features of high recognition precision.
Reliability Analysis Based on Efficient Simulation
Authors: Gong Xian Sheng , Zhang Gan Qing
Published: November 2011

In the practical engineering, to solve the small failure probabilities with correlated high-dimensional variables, the subset simulation (SS) is combined together with the Monte Carlo and importance sampling (IS) method. The samples from the probability density functions (PDF) of the importance sampling are used to construct the intermediate failure events, by which the small failure probabilities are turned into a Markov chain (MC), which is a continuous product made of a series large failure probability or conditional failure probability (CFP) which is easily answered, on which the structural reliability can be efficiently simulated by directly obtaining the samples with correlated ones. Finally, the 3 planet carriers of 3 grade planetary reducers in shield tunneling machine(STM) are as examples to check the algorithm above, the results show that the SS of the IS with correlated variables can highly simulate failure probability.
Effect of Calcium Nutrient on Calcium Distribution and Ultrastructure of Cell and Chloroplast in Bunching Onion Leaf
Authors: Liu Hou Cheng , Liu Wen Peng , Song Shi Wei , Sun Guang Wen , Chen Ri Yuan
Published: November 2011

Effect of calcium nutrient on calcium distribution and ultrastructure of cell and chloroplast in Bunching Onion (Allium fistulosum L. var. caespitosum Makino) leaf was studied in sands with 4 Ca2+ treatments (0, 40, 80 and 160 mg/L ), in which the solution was Hoagland's. Localization and distribution of calcSuperscript textium and the influence of calcium nutrition on cell ultrastructure were observed by transmission electron microscopy combined with in situ precipitation of calcium with potassium pyroantimonate technique. The results showed that Ca2+ were mainly located in cell membrane, vacuoles, envelope of chloroplast and intercellular space in normal cells of bunching onion, however, Ca2+ was found to compartment in cytosol in large quantity, and the release of membrane-associated Ca2+ to cytosol and wall-associated Ca2+ to the intercellular spaces was observed in Ca-deficient leaves. In serious Ca-deficient leaves, Ca2+ quantities in cell decreased. Under Ca-deficiency, chloroplast membranes, plasma membranes and nuclear membranes were damaged, and cell walls disassociated, an enlarged space could be found between cells. In serious Ca-deficient leaves, cell compartmentation was destroyed, chloroplast deformed, plasma separated from cell wall, then whole cell constricted.