bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the Driver's Recognitive Characteristics to Crossing Pedestrians at Night for the Maximum Speed Limit and Lighting Index in China
Authors: Xu Liang , Cheng Guozhu , Guo Yufeng , Hu Liwei , Mo Xuanyan
Published: March 2015

Aiming to reduce the number of crashes caused by speeding at night on road section with a crosswalk, a study was conducted on the maximum speed limit and safe average luminance at night. In order to investigate the potential relationship between drivers’ recognitive characteristics and driving speed under different road lighting features, data of remaining driving time (period from the time that crossing pedestrian is recognized to the time that vehicle arrives at crosswalk with an uniform speed) were recorded. The results of the data analysis show that it is more difficult for divers to recognize crossing pedestrian at night when a single pedestrian is statistic and wears dark clothes. The remaining driving time decreases with the increase of driving speed and the decrease of road luminance. With the collected data, several multivariate nonlinear regression models were established to capture the relationship among the variables of remaining driving time at night, the driving speed, and the average luminance. Then the modeling results were used to develop the reasonable speed limit and safe average luminance by physical equations. The case studies are also introduced at the end of the paper.
Error Factor and Mathematical Model of Positioning with Odometer Wheel
Authors: Wang Zegen , Tan Jing , Sun Zhengchao
Published: March 2015

High positioning accuracy with odometer wheel is of great importance for internal pipeline defect detection. In current research, the qualitative analysis is focused on and the accumulation characteristics of positioning errors are not shown. Based on this, the models and the accumulation characteristics of positioning errors are investigated in this paper. The errors are classified into systematic errors and random errors. Systematic errors consist of difference between actual and nominal diameters, diameter difference among wheels, and terminal error. Random errors consist of initial point error, weld error, and oversized clearance. The mathematical models of the errors are obtained by the methods of quantitative analysis and contrastive analysis. Through calculation examples, the results show the relationship of the errors and the effect of each error on total error. Diameter calibration and detection in sections are proposed to improve the positioning accuracy.
Analytical Solutions for Functionally Graded Beams under Arbitrary Distributed Loads via the Symplectic Approach
Authors: Zhao Li , Gan Weizhong
Published: March 2015

A novel symplectic approach is employed in the analysis of homogenous and functionally graded beams subjected to arbitrary tractions on the lateral surfaces. Two models of functionally graded beams are heterogeneous in the sense that the material properties are exponential functions of the length and thickness, respectively. Within the symplectic framework, the method of separation of variables alone with the eigenfunction expansion technique is adopted to obtain the exact analysis of displacement and stress fields. The complete solutions include homogenous solutions with coefficients to be determined by two end boundary conditions and particular solutions satisfying the lateral boundary conditions. Two examples are presented for functionally graded beams to demonstrate the effects of material inhomogeneity. The efficiency and accuracy of the symplectic analysis are shown through numerical results.
Occlusion Processing and Tracking Technology of Multiple Targets in Traffic Video Detection
Authors: Zhao Yingying , Jiang Sheng , Qu Zhaowei , Tao Pengfei
Published: March 2015

This paper reports an algorithm of traffic multiple targets occlusion processing and tracking based on both the prediction of Kalman filtering operators and the processing of the PCA-SIFT (Principle Component Analysis Scale Invariant Feature Transform) feature with the active operators. The Kalman filtering operators are used for both the prediction of occlusion event and the fast location of occlusion area. The template for each target in the occlusion area is built and the PCA-SIFT feature with the active contour operators is used to estimate and trace the multiple targets separately in the area. Through updating, the occlusion processing and tracking of multiple targets continue until the occlusion ends. Obtained results have shown that the algorithm in the paper can solve multiple targets occlusion and tracking effectively and accurately, comparing with the real trajectories.
Feasibility Study on the Implementation of Cubic Motion Curve for Vehicle Trajectory Planning
Authors: Ghani M. F. Mat , Taib J. Mohd , Dzakaria A.
Published: March 2015

Cubic Motion curve has been introduced to integrate the information of path and motion. Since this is a new approach, a feasibility study has been carried out to analyse the practicality of Cubic Motion curves used as the input for the study of vehicle dynamic response. This study requires the development of three modules, namely, the Cubic Motion module, the vehicle dynamic model, the driver model (VDM-DM) module, and, lastly, the integrated module. The Cubic Motion module will generate Cubic Motion curve. The VDM-DM module applies the 2 DOF bicycle model and links it with Reński's driver model. Finally, an integrated module will merge both previous modules as a complete system for trajectory and vehicle response as the output. The double lane change and the Slalom test were the case studies used to develop an understanding of the applicability of the three types of Cubic Motion input, namely, natural, adjusted tangent, and additional vertex cubic motion. The finding of this study is that Cubic Motion is in fact a compact representation of curve with motion attributes and can be directly associated with a vehicle dynamic response study.
A Cooperative Control Method for Fully Mechanized Mining Machines Based on Fuzzy Logic Theory and Neural Networks
Authors: Tan Chao , Si Lei , Zhou Xin , Wang Zhongbin , Wang Kai
Published: March 2015

In a fully mechanized mining face, the coordinated control of coal mining machines has a significant promoting effect to perfect the mining environment and improve the efficiency of coal production and has become a research focus all over the world. In this paper, a cooperative control method based on the integration of fuzzy logic theory and neural networks was proposed. The improved Elman neural network (ENN) through a threshold strategy was presented to predict the running parameters of coal mining machines. On the basis of coupling analysis of coal mining machines, the expert knowledge base of scraper conveyor was established based on fuzzy logic theory. Furthermore, the probabilistic neural network (PNN) was applied to evaluate the running status of scraper conveyor, and the cooperative control flow was designed and analyzed. Finally, a simulation example was provided and the comparison results illustrated that the proposed method was feasible and superior to the manual control.
The Bus Station Spacing Optimization Based on Game Theory
Authors: Zheng Changjiang , Zheng Shukang , Ma Genghua
Published: March 2015

With the development of city, the problem of traffic is becoming more and more serious. Developing public transportation has become the key to solving this problem in all countries. Based on the existing public transit network, how to improve the bus operation efficiency, and reduce the residents transit trip cost has become a simple and effective way to develop the public transportation. Bus stop spacing is an important factor affecting passengers’ travel time. How to set up bus stop spacing has become the key to reducing passengers’ travel time. According to comprehensive traffic survey, theoretical analysis, and summary of urban public transport characteristics, this paper analyzes the impact of bus stop spacing on passenger in-bus time cost and out-bus time cost and establishes in-bus time and out-bus time model. Finally, the paper gets the balance best station spacing by introducing the game theory.
Connection Facility Layout Model of Subway Stations
Authors: Yao Liya , Sun Lishan , Wang Wuhong , Xia Xinfeng
Published: March 2015

As the key node of public transportation system, subway station has many functions such as attracting and distributing passengers and guiding the transfer from various traffic modes to subway. However, the poor facility scale and layout around subway stations in practice usually cause the inconvenience of transfer and low transfer efficiency, which causes the declination of travel efficiency and even loose of subway passengers. Taking subway stations as the study objects, this paper has emphasis on the connection characters between various traffic modes and subway stations. Considering the attraction region, the total transfer time, transfer distance, and connection cost were selected to form the efficiency index of connection layout of subway stations. Data envelopment analysis (DEA) model is applied in the quantization of traffic resource consumption and output. At last, connection facility layout model of subway stations was established with the aim of improving the transfer efficiency. Meaningful results were obtained from the connection layout model of subway stations, which guide the planning and designing of the transfer facilities around subway stations.
Application of Computational-Experimental Methods for Designing Optimized Semitrailer Axle Supports
Authors: Valladares David , Carrera Marco , Castejon Luis , Martin Carlos
Published: March 2015

Computational and experimental methods were applied to the design and optimization of a semitrailer axle support subjected to fatigue loads. Numerical results based on the finite element method (FEM) were correlated with extensometric tests to assess the accuracy of the computational method. This paper is focused on the “minimum radius manoeuvre.” This situation represents the highly critical load case occurring in a semitrailer operation where the tractor vehicle pulls the semitrailer's kingpin at approximately 90° with respect to its longitudinal axis, and high stress and strain phenomena take place in the axle supports’ structure. Loads and boundary conditions that correspond to this load case were first adjusted by means of experimental tests and could be later applied to each semitrailer axle support in the numerical model. In this analysis, the stress-strain elastic-plastic curves of the base material, the welding, and the HAZ have been incorporated to the numerical models. Fatigue S- N curves combined with the maximum Von Mises equivalent stresses obtained in the computational analysis provided a maximum number of cycles that the semitrailer axle support could reach in case of the minimum radius manoeuvre being applied to the vehicle in a repeated manner. The initial design could then be optimized to improve its fatigue life.
Multiobjective Optimization Design of Double-Row Blades Hydraulic Retarder with Surrogate Model
Authors: Chunbao Liu , Linshan Ge , Wenxing Ma , Xuesong Li
Published: March 2015

For the design of double-row blades hydraulic retarder involves too many parameters, the solution process of the optimal parameter combination is characterized by the large calculation load, the long calculation time, and the high cost. In this paper, we proposed a multiobjective optimization method to obtain the optimal balanced solution between the braking torque and volume of double-row blades hydraulic retarder. Moreover, we established the surrogate model for objective function with radial basis function (RBF), thus avoiding the time-consuming three-dimensional modeling and fluid simulation. Then, nondominated sorting genetic algorithm-II (NSGA-II) was adopted to obtain the optimal combination solution of design variables. Moreover, the comparison results of computational fluid dynamics (CFD) values of the optimal combination parameters and original design parameters indicated that the multiobjective optimization method based on surrogate model was applicable for the design of double-row blades hydraulic retarder.
Effect of Nominal Chip Thickness on Stability of Interrupted Turning
Authors: Chen Lihai , Zhang Lianhong , Man Jia
Published: March 2015

A new dynamic cutting force model with nominal chip thickness is presented for predicting the stability of interrupted turning, in where the dynamical cutting force is defined by a function of nominal chip thickness and dynamical chip thickness. The stability lobes of interrupted turning are obtained based on full-discretization method and Floquet theory. Both numerical and experimental tests demonstrate that there is a strong correlation between the nominal chip thickness and the interrupted turning stability, and the proposed model is proved effective for the interrupted turning process.
Application of Taguchi Method to the Optimization of a-C:H Coatings Deposited Using Ion Beam Assisted Physical Vapor Deposition
Authors: Kao W. H. , Su Y. L. , Horng J. H. , Yao S. H. , Huang H. C.
Published: March 2015

The Taguchi design method is used to optimize the adhesion, hardness, and wear resistance properties of a-C:H coatings deposited on AISI M2 steel substrates using the ion beam assisted physical vapor deposition method. The adhesion strength of the coatings is evaluated by means of scratch tests, while the hardness is measured using a nanoindentation tester. Finally, the wear resistance is evaluated by performing cyclic ball-on-disc wear tests. The Taguchi experimental results show that the optimal deposition parameters are as follows: a substrate bias voltage of 90 V, an ion beam voltage of 1 kV, an acetylene flow rate of 21 sccm, and a working distance of 7 cm. Given these optimal processing conditions, the a-C:H coating has a critical load of 99.8 N, a hardness of 25.5 GPa, and a wear rate of 0.4 × 10−6 mm3/Nm.
Structure Optimization of Force Feedback Device in Virtual Cardiovascular Surgery
Authors: Hu Zhi , Cai Ping
Published: March 2015

In virtual cardiovascular surgery, the force feedback is transmitted via the flexible guide wire. In the force transmission, disturbance always occurs due to flexible deformation, and this would make it hard to ensure immersion by rendering the force feedback in actuator. As the effect of flexible deformation is related to the length of guide wire, experiment is designed to assess the force transmission of guide wire when the length between the actuator and operating point changes. In this paper, three indexes are proposed to search for the length between the actuator and the device entrance. And the optimal scope length of guide wire is found out to ensure the guide wire has the best performance for the force transmission.
Numerical Investigation on Dynamic Crushing Behavior of Auxetic Honeycombs with Various Cell-Wall Angles
Authors: Zhang Xin-chun , Ding Hai-min , An Li-qiang , Wang Xiao-lei
Published: March 2015

Auxetic honeycombs have proven to be an attractive advantage in actual engineering applications owing to their unique mechanical characteristic and better energy absorption ability. The in-plane dynamic crushing behaviors of the honeycombs with various cell-wall angles are studied by means of explicit dynamic finite element simulation. The influences of the cell-wall angle, the impact velocity, and the edge thickness on the macro/microdeformation behaviors, the plateau stresses, and the specific energy absorption of auxetic honeycombs are discussed in detail. Numerical results show, that except for the impact velocity and the edge thickness, the in-plane dynamic performances of auxetic honeycombs also rely on the cell-wall angle. The “> <”-mode local deformation bands form under low- or moderate-velocity impacting, which results in lateral compression shrinkage and shows negative Poisson's ratio during the crushing. For the given impact velocity, the plateau stress at the proximal end and the energy-absorbed ability can be improved by increasing the negative cell angle, the relative density, the impact velocity, and the matrix material strength. When the microcell parameters are the constant, the plateau stresses are proportional to the square of impact velocity.
Distribution Manner of Compaction Circular Cylinders in Through-Active-Mask Electrochemical Machining
Authors: Li Hansong , Wang Guoqian , Zheng Xin , Zeng Yongbin
Published: March 2015

Electrochemical machining is widely used in the processing of difficult-to-machine metal materials. And through-mask electrochemical machining is a very important technology in the processing array structure of difficult-to-cut metal materials. Traditional through-mask electrochemical machining always uses a photoresist as the mask. The production process of a mask is complicated, and the mask cannot be reused. In this paper, through-active-mask electrochemical machining to process array structure in difficult-to-machine metal materials was investigated. Compared with traditional electrochemical machining masks, a copper-clad laminate is used to make the mask by mechanical machining in through-active-mask electrochemical machining. Also, the mask does not stick together with the workpiece but covers the workpiece by mechanical compaction, so the mask can be reused. In order to ensure the mask is in close contact with the workpiece, we need to arrange many compaction circular cylinders within the flow channel. The influences on electrolyte flow of compaction circular cylinders were investigated. The distribution of the compaction circular cylinders affects the electrolyte flow state, thereby affecting the processing. By analyzing the electrolyte flow state for the different distributions of compaction circular cylinders, one can find the best distribution of compaction circular cylinders for the required processing.
Driver Eye State Classification Based on Cooccurrence Matrix of Oriented Gradients
Authors: Zhang Bo , Wang Wenjun , Cheng Bo
Published: March 2015

Accurate detection of driver's eye state by computer vision is critical to driver drowsiness monitoring. The histogram of oriented gradients (HOG) is commonly used as descriptive feature of eye image for state classification. However, HOG often suffers from the limit of local gradient information. This paper proposes a new HOG-like feature of eye image, called cooccurrence matrix of oriented gradients (CMOG), for the purpose of more effectively classifying the eye state. By introducing the cooccurrence matrix, the CMOG enhances the ability of describing global gradient information of eye images. The ZJU eye blink database is used as the baseline images for performance comparison. The classification results show that the accuracy of CMOG reaches up to 95.9% in comparison with 91.9% by HOG under this database.
Numerical Analysis of Thermal Mixing in a Swirler-Embedded Line-Heater for Flow Assurance in Subsea Pipelines
Authors: Park Jang Min , Oh Dong-Wook , Lee Jungho
Published: March 2015

Flow assurance issue in subsea pipelines arises mainly due to hydrate plugs. We present a new line-heater for prevention of hydrate plug formation in subsea pipelines. The line heater has modular compact design where an electrical heater and a swirl generator are embedded inside the housing pipe so that the stream can be heated efficiently and homogeneously. In this paper, flow and heat transfer characteristics of the line heater are investigated numerically, with a particular emphasis on the mixing effect due to the swirl generator.
Identification of Clearance and Contact Stiffness in a Simplified Barrel-Cradle Structure of Artillery System
Authors: Li Bing , Quan Shuanglu , Jin Wei , Han Luofeng , Liu Jie , He Anqi
Published: March 2015

In gun barrel-cradle structure, the presence of clearance usually changes the dynamic response of muzzle and results in shooting dispersion (under continuous firing condition). The parameter estimation of such clearance nonlinear system is the prerequisite for establishing quantitative relation between the clearance and muzzle disturbance. In this paper, the restoring force surface (RFS) method and the nonlinear identification through feedback of outputs (NIFO) method are first combined for parameter identification in a simplified barrel-cradle structure. With the RFS method, clearance value can be obtained by analyzing the restoring force plot. Then the contact stiffness can be identified by using NIFO method. This identification process is verified in a single-degree-of-freedom (SDOF) system with clearance. To adapt to the rigid-flexible coupled beam system with clearances which is simplified from the barrel-cradle structure, a modification for the combined method mentioned above is proposed. The core idea of the modification is reducing the continuous system to multiple-degree-of-freedom (MDOF) system to reserve the nonlinear characteristics through modal transformation matrix. The advantage of this transformation is that the linear parts of the MDOF systems are decoupled, which greatly reduces the difficulty of identification. The simulation results have shown the effectiveness of current method.
Driver's Behavior and Decision-Making Optimization Model in Mixed Traffic Environment
Authors: Wang Xiaoyuan , Wang Jianqiang , Zhang Jinglei , Ban Xuegang (Jeff)
Published: March 2015

Driving process is an information treating procedure going on unceasingly. It is very important for the research of traffic flow theory, to study on drivers' information processing pattern in mixed traffic environment. In this paper, bicycle is regarded as a kind of information source to vehicle drivers; the “conflict point method” is brought forward to analyze the influence of bicycles on driving behavior. The “conflict” is studied to be translated into a special kind of car-following or lane-changing process. Furthermore, the computer clocked scan step length is dropped to 0.1 s, in order to scan and analyze the dynamic (static) information which influences driving behavior in a more exact way. The driver's decision-making process is described through information fusion based on duality contrast and fuzzy optimization theory. The model test and verification show that the simulation results with the “conflict point method” and the field data are consistent basically. It is feasible to imitate driving behavior and the driver information fusion process with the proposed methods. Decision-making optimized process can be described more accurately through computer precision clocked scan strategy. The study in this paper can provide the foundation for further research of multiresource information fusion process of driving behavior.
Dynamic Self-Adaptive Reliability Control for Electric-Hydraulic Systems
Authors: Wan Yi , Huang Hailong , Tian Jing
Published: March 2015

The high-speed electric-hydraulic proportional control is a new development of the hydraulic control technique with high reliability, low cost, efficient energy, and easy maintenance; it is widely used in industrial manufacturing and production. However, there are still some unresolved challenges, the most notable being the requirements of high stability and real-time by the classical control algorithm due to its high nonlinear characteristics. We propose a dynamic self-adaptive mixed control method based on the least squares support vector machine (LSSVM) and the genetic algorithm for high-speed electric-hydraulic proportional control systems in this paper; LSSVM is used to identify and adjust online a nonlinear electric-hydraulic proportional system, and the genetic algorithm is used to optimize the control law of the controlled system and dynamic self-adaptive internal model control and predictive control are implemented by using the mixed intelligent method. The internal model and the inverse control model are online adjusted together. At the same time, a time-dependent Hankel matrix is constructed based on sample data; thus finite dimensional solution can be optimized on finite dimensional space. The results of simulation experiments show that the dynamic characteristics are greatly improved by the mixed intelligent control strategy, and good tracking and high stability are met in condition of high frequency response.
Motion Structural Optimization Strategy for Rhombic Element Based Foldable Structure
Authors: Jeong Seung Hyun , Heo Jae Chung , Yoon Gil Ho
Published: March 2015

This research presents a new systematical design approach of foldable structure composed of several rhombic elements by applying genetic algorithm. As structural shapes represented by a foldable structure can be easily and dramatically morphed by manipulating rotational directions and angle of joints, the foldable structure has been used for various elementary structural members and engineering mechanisms. However a systematic design approach determining detail rotational angle and directions of unit cells for arbitrary shaped target areas has not been proposed yet. This research contributes to it by developing a new structural optimization method determining optimal angle and rotation directions to cover arbitrary shaped target areas of interest with aggregated rhombic elements. To achieve this purpose, we present an optimization formulation minimizing the sum of distances between each reference joint of an arbitrary shaped target area and its closest outer joints of foldable structure. To find out the outer joint set of a given foldable structure, an efficient geometric analysis method based on Delaunay triangulation is also developed and implemented. To show the validity and limitations of the present approach, several foldable structure design problems for two-dimensional arbitrary shaped target areas are solved with the present optimization procedure.
Simulation of Sedimentation of a Sphere in a Viscous Fluid Using the Lattice Boltzmann Method Combined with the Smoothed Profile Method
Authors: Alapati Suresh , Che Woo Seong , Suh Yong Kweon
Published: March 2015

We conducted a numerical study on the motion of a solid sphere settling under gravity in a viscous fluid using the lattice Boltzmann method combined with the smoothed profile method (SPM). The coupling of lattice Boltzmann fluid and a spherical particle is treated by introducing a body force term to the Boltzmann kinetic equation. For verification, we applied our numerical code to the simulation of flow over a static sphere and compared the results with previously published data. Later, we simulated the sedimentation process of a sphere inside a closed container. Our simulation results of the sphere's settling velocity and fluid velocity contours at various Reynolds numbers are in good agreement with the corresponding experimental results. Finally, we analyzed the accuracy of the present SPM for different forms for the smoothed profile function at various interface thicknesses and grid sizes.
Environmentally Conscious Polishing System Based on Robotics and Artificial Vision
Authors: Dieste J. A. , Fernández A. , Javierre C. , Santolaria J.
Published: March 2015

Polishing process is one of the manufacturing issues that are essential in the production flow, but it generates the major amount of defects on parts. Finishing tasks in which polishing is included are performed in the final steps of the manufacturing sequence. Any defect in these steps impliesrejection of the part, generating a big amount of scrap and generating a huge amount of energy consumption, emission, and time to manufacture and replace the rejected part. Traditionally polishing process has not evolved during the last 30 years, while other manufacturing processes have been automated and technologically improved. Finishing processes (grinding and polishing), are still manually performed, especially in freeform surface parts, but to be sustainable some development and automation have to be introduced. This research proposes a novel polishing system based on robotics and artificial vision. The application of this novel system has allowed reducing the failed parts due to finishing process down to zero percent from 28% of rejected parts with manual polishing process. The reduction in process time consumption, and amount of scrapped parts, has reduced the energy consumption up to 30% in finishing process and 20% in whole manufacturing process for an injection moulded aluminium part for automotive industry with high production volumes.
Application of Modal Parameter Estimation Methods for Continuous Wavelet Transform-Based Damage Detection for Beam-Like Structures
Authors: Qiu Zhi , Lee C.-M. , Xu Z. H.
Published: March 2015

This paper presents a hybrid damage detection method based on continuous wavelet transform (CWT) and modal parameter identification techniques for beam-like structures. First, two kinds of mode shape estimation methods, herein referred to as the quadrature peaks picking (QPP) and rational fraction polynomial (RFP) methods, are used to identify the first four mode shapes of an intact beam-like structure based on the hammer/accelerometer modal experiment. The results are compared and validated using a numerical simulation with ABAQUS software. In order to determine the damage detection effectiveness between the QPP-based method and the RFP-based method when applying the CWT technique, the first two mode shapes calculated by the QPP and RFP methods are analyzed using CWT. The experiment, performed on different damage scenarios involving beam-like structures, shows that, due to the outstanding advantage of the denoising characteristic of the RFP-based (RFP-CWT) technique, the RFP-CWT method gives a clearer indication of the damage location than the conventionally used QPP-based (QPP-CWT) method. Finally, an overall evaluation of the damage detection is outlined, as the identification results suggest that the newly proposed RFP-CWT method is accurate and reliable in terms of detection of damage locations on beam-like structures.
Driving Simulator Study of Effect of Inside Shoulder on Vehicle Operation
Authors: Ding Han , Zhao Xiaohua , Rong Jian , Zhong Liande
Published: March 2015

According to the Chinese Design Specification for Highway Alignment (JTG D20-2006), eight-lane expressways should be paved with an inside shoulder of 2.5 m; however, this regulation is rarely obeyed in engineering practice. On the basis of driving simulator experiment, this research examined the impacts of inside shoulder on vehicle operation with and without the speed limitation. A virtual scenario, consisting of five expressways with different inside shoulder widths, was created and displayed in driving simulator, and vehicle operational data—speed and lane position—were recorded. Authors used analysis of variance (ANOVA) and contrast analysis to examine whether inside shoulder width had statistically significant effects on travel speed and lane position. Analytical results indicated that there is a kind of quadratic relationship between inside shoulder width and driver's speed choice, while driver's speed choice is not significantly affected by inside shoulder width. What is more, inside shoulder width has statistically significant effects on vehicle's lane positions, and vehicle's lane position is negatively correlated to inside shoulder width. Specifically, the vehicle can be maintained at the center of lane when the inside shoulder width is 2.5 m.
Investigation on Vibration Characteristics in a Centrifugal Pump with Special Slope Volute
Authors: Zhang Ning , Yang MinGuan , Gao Bo , Li Zhong
Published: March 2015

Vibration is one of the main problems which should be considered seriously in designing and operating a centrifugal pump. In this paper, a special slope volute was proposed to reduce vibration level of centrifugal pump. The goal of this paper was to analyze vibration characteristics of slope volute pump and provide a new method to reduce vibration energy in centrifugal pump. Experiments were carried out to obtain vibration signals at different flow rates of slope volute pump, which were compared with conventional spiral volute pump. Results show that vibration level is closely related to flow structure interior pump. At low flow rates, especially, vibration energy increases rapidly with the onset of rotating stall. Rotor-stator interaction mechanism changes when adopting slope volute. In slope volute pump, the peaks in power spectra correspond to different harmonics of fBPF at three measuring directions; however, in spiral volute pump, the predominant components always correspond to 2 fBPF. From comparison of vibration level in different frequency bands, it is found that vibration level of slope volute pump is smaller than conventional spiral volute pump. So vibration energy of centrifugal pump can be reduced effectively using slope volute.
Hierarchical Control Strategy for Active Hydropneumatic Suspension Vehicles Based on Genetic Algorithms
Authors: Feng Jinzhi , Matthews Christian , Zheng Songlin , Yu Fan , Gao Dawei
Published: March 2015

A new hierarchical control strategy for active hydropneumatic suspension systems is proposed. This strategy considers the dynamic characteristics of the actuator. The top hierarchy controller uses a combined control scheme: a genetic algorithm- (GA-) based self-tuning proportional-integral-derivative controller and a fuzzy logic controller. For practical implementations of the proposed control scheme, a GA-based self-learning process is initiated only when the defined performance index of vehicle dynamics exceeds a certain debounce time threshold. The designed control algorithm is implemented on a virtual prototype and cosimulations are performed with different road disturbance inputs. Cosimulation results show that the active hydropneumatic suspension system designed in this study significantly improves riding comfort characteristics of vehicles. The robustness and adaptability of the proposed controller are also examined when the control system is subjected to extremely rough road conditions.
Adaptive RBF Neural Vibration Control of Flexible Structure
Authors: Hu Tongyue , Fei Juntao
Published: March 2015

An adaptive sliding mode controller using radial basis function (RBF) network is proposed to approximate the unknown system dynamics for cantilever beam. Neural network controller is designed to approximate the unknown system model. In the presence of unknown model uncertainties and external disturbances, sliding mode controller is employed to compensate for such system nonlinearities and improve the tracking performance. Online neural network (NN) weight tuning algorithms are designed based on Lyapunov stability theory, which can guarantee bounded tracking errors as well as bounded NN weights. Numerical simulation for cantilever beam is investigated to verify the effectiveness of the proposed adaptive neural control scheme and demonstrate the satisfactory vibration suppression performance.
Evaluation of Effects of Warning Sign Position on Driving Behavior in Horizontal Sharp Curves
Authors: Zhao Xiao-hua , Huang Li-hua , Guan Wei , Rong Jian
Published: March 2015

In present time, the guidelines on warning sign position in the China National Standard lack detailed and standard regulations of placing warning signs on sharp curves, which may cause road safety problems. Therefore, this paper briefly discussed how to optimize the position of a warning sign on a sharp curve through a driving simulator experiment. This study concluded that a warning sign placed at different positions prior to a sharp curve will have different influence ranges for drivers approaching and negotiating the curve. Meanwhile, different positions of a warning sign imposed different effect obviously on the adjustment of vehicle's lane position on sharp curves with the same radius, especially at the midpoint of a sharp curve. The evaluation results of five positions (0 m, 50 m, 100 m, 200 m, and 400 m in advance) showed that only when the warning signs were placed 100 m or 200 m prior to sharp curves, can they achieve positive influence on driving behavior. On this basis, the authors look forward to providing rationalization proposals in selecting the best position of a warning sign on a sharp curve for the engineering implementation and national standard.
Thyroid Hormone and P-Glycoprotein in Tumor Cells
Authors: Davis Paul J. , Incerpi Sandra , Lin Hung-Yun , Tang Heng-Yuan , Sudha Thangirala , Mousa Shaker A.
Published: March 2015

P-glycoprotein (P-gp; multidrug resistance pump 1, MDR1; ABCB1) is a plasma membrane efflux pump that when activated in cancer cells exports chemotherapeutic agents. Transcription of the P-gp gene (MDR1) and activity of the P-gp protein are known to be affected by thyroid hormone. A cell surface receptor for thyroid hormone on integrinαvβ3 also binds tetraiodothyroacetic acid (tetrac), a derivative of L-thyroxine (T4) that blocks nongenomic actions of T4and of 3,5,3′-triiodo-L-thyronine (T3) atαvβ3. Covalently bound to a nanoparticle, tetrac as nanotetrac acts at the integrin to increase intracellular residence time of chemotherapeutic agents such as doxorubicin and etoposide that are substrates of P-gp. This action chemosensitizes cancer cells. In this review, we examine possible molecular mechanisms for the inhibitory effect of nanotetrac on P-gp activity. Mechanisms for consideration include cancer cell acidification via action of tetrac/nanotetrac on the Na+/H+exchanger (NHE1) and hormone analogue effects on calmodulin-dependent processes and on interactions of P-gp with epidermal growth factor (EGF) and osteopontin (OPN), apparently viaαvβ3. Intracellular acidification and decreased H+efflux induced by tetrac/nanotetrac via NHE1 is the most attractive explanation for the actions on P-gp and consequent increase in cancer cell retention of chemotherapeutic agent-ligands of MDR1 protein.
The Automatic Drilling System of 6R-2P Mining Drill Jumbos
Authors: Wang Yujun , Fang Can , Jiang Qimi , Ahmed Syed Naeem
Published: March 2015

In order to improve the efficiency of underground mining and tunneling operations and to realize automatic drilling, it is necessary to develop the automation system for large drill jumbos. This work focuses on one such mining drill jumbo which is actually a redundant robotic manipulator with eight degrees of freedom, because it has six revolute joints and two prismatic joints. To realize the autonomous drilling operation, algorithms are proposed to calculate the desired pose of the end-effector and to solve the inverse kinematics of the drill jumbo, which is one of the key issues for developing the automation system. After that, a control strategy is proposed to independently control the eight joint variables using PID feedback control approaches. The simulation model is developed in Simulink. As the closed-loop controllers corresponding to all joints are local and independent of each other, the whole system is not a closed-loop feedback control. In order to estimate the possible maximal pose error, the analysis of the pose error caused by the errors of the joint variables is conducted. The results are satisfactory for mining applications and the developed automation system is being applied in the drill jumbos built by Mining Technologies International Inc.
Circulating Soluble Neuropilin-1 in Patients with Early Cervical Cancer and Cervical Intraepithelial Neoplasia Can Be Used as a Valuable Diagnostic Biomarker
Authors: Yang Shouhua , Cheng Henghui , Huang Zaiju , Wang Xiaoling , Wan Yinglu , Cai Jing , Wang Zehua
Published: March 2015

Objective. To investigate soluble neuropilin-1 (sNRP-1) in circulating and NRP-1 protein in cervical tissues from patients with cervical cancer or cervical intraepithelial neoplasia (CIN).Methods. sNRP-1 was measured in 64 preoperative patients and 20 controls. NRP-1 protein in cervical tissue was detected in 56 patients and 20 controls.Results. Both sNRP-1 and NRP-1 proteins were correlated with stage. sNRP-1 presented a high diagnostic ability of cervical cancer and CIN, with a sensitivity of 70.97% and a specificity of 73.68%.Conclusions. sNRP-1 in circulating can serve as a possible valuable diagnostic biomarker for cervical cancer and CIN.
Early Life Cognitive Abilities and Body Weight: Cross-Sectional Study of the Association of Inhibitory Control, Cognitive Flexibility, and Sustained Attention with BMI Percentiles in Primary School Children
Authors: Wirt Tamara , Schreiber Anja , Kesztyüs Dorothea , Steinacker Jürgen M.
Published: March 2015

The objective of this study was to investigate the association of different cognitive abilities with children’s body weight adjusted for further weight influencing sociodemographic, family, and lifestyle factors. Cross-sectional data of 498 primary school children (7.0 ± 0.6 years; 49.8% boys) participating in a health promotion programme in southwest Germany were used. Children performed a computer-based test battery (KiTAP) including an inhibitory control task (Go-Nogo paradigm), a cognitive flexibility task, and a sustained attention task. Height and weight were measured in a standardized manner and converted to BMI percentiles based on national standards. Sociodemographic features (migration background and parental education), family characteristics (parental body weight), and children’s lifestyle (TV consumption, physical activity, consumption of sugar-sweetened beverages and breakfast habits) were assessed via parental questionnaire. A hierarchical regression analysis revealed inhibitory control and cognitive flexibility to be significant cognitive predictors for children’s body weight. There was no association concerning sustained attention. The findings suggest that especially cognitive abilities known as executive functions (inhibitory control and cognitive flexibility) are associated with children’s body weight. Future longitudinal and intervention studies are necessary to investigate the directionality of the association and the potential of integrating cognitive training in obesity prevention strategies. This trial is registered with ClinicalTrials.govDRKS00000494.
Associations of Parental Influences with Physical Activity and Screen Time among Young Children: A Systematic Review
Authors: Xu Huilan , Wen Li Ming , Rissel Chris
Published: March 2015

Parents play a critical role in developing and shaping their children’s physical activity (PA) and sedentary behaviours, particularly in the early years of life. The aim of this systematic review is to identify current literature investigating associations of parental influences with both PA and screen time in young children. This systematic review was conducted in November 2013 using 6 electronic databases covering research literature from January 1998 to November 2013. Thirty articles that met inclusion criteria were identified. These studies covered five important aspects of parenting: (1) parenting practices; (2) parents’ role modelling; (3) parental perceptions of children’s PA and screen viewing behaviours; (4) parental self-efficacy; and (5) general parenting style. Findings suggest that parents’ encouragement and support can increase children’s PA, and reducing parents’ own screen time can lead to decreased child screen time. Improving parenting practices, parental self-efficacy or changing parenting style may also be promising approaches to increasing PA time and decreasing screen time of young children.
Comprehensive Review on Betulin as a Potent Anticancer Agent
Authors: Król Sylwia Katarzyna , Kiełbus Michał , Rivero-Müller Adolfo , Stepulak Andrzej
Published: March 2015

Numerous plant-derived substances, and their derivatives, are effective antitumour and chemopreventive agents. Yet, there are also a plethora of tumour types that do not respond, or become resistant, to these natural substances. This requires the discovery of new active compounds. Betulin (BE) is a pentacyclic triterpene and secondary metabolite of plants abundantly found in the outer bark of the birch treeBetulaceaesp. BE displays a broad spectrum of biological and pharmacological properties, among which the anticancer and chemopreventive activity attract most of the attention. In this vein, BE and its natural and synthetic derivatives act specifically on cancer cells with low cytotoxicity towards normal cells. Although the antineoplastic mechanism of action of BE is not well understood yet, several interesting aspects of BE’s interactions are coming to light. This review will summarize the anticancer and chemopreventive potential of BEin vitroandin vivoby carefully dissecting and comparing the doses and tumour lines used in previous studies, as well as focusing on mechanisms underlying its activity at cellular and molecular level, and discuss future prospects.
Genetic Algorithm and Its Performance Analysis for Scheduling a Single Crane
Authors: Xie Xie , Zheng Yongyue , Li Yanping
Published: March 2015

This paper studies a single crane scheduling problem arising in the cold-rolling material warehouse in an iron and steel enterprise. A set of coils stored in two levels are needed to be picked up and transported to designated positions. If a required coil is at the upper level, it can be picked up right away and transported to its designated position (transportation operation). A required coil at the lower level cannot be picked up until all its blocking coils at the upper level are moved to other positions (shuffling operation). One overhead crane is used to perform all the transportation and shuffling operations. Our problem is to schedule the crane operations so as to all required coils retrieve to their designated positions in the shortest possible time (makespan). Since the problem is shown to be NP-hard, a genetic algorithm (GA) is proposed. We identify some analytical properties which enable us to develop an effective heuristic algorithm as initial solutions of the GA. We further analyze its performance from the worst-case point of view. To evaluate the average performances, a numerical test compared with some existing methods is carried out and its results show the good quality of the proposed algorithm.
Computational Selection of RNA Aptamer against Angiopoietin-2 and Experimental Evaluation
Authors: Hu Wen-Pin , Kumar Jangam Vikram , Huang Chun-Jen , Chen Wen-Yih
Published: March 2015

Angiogenesis plays a decisive role in the growth and spread of cancer and angiopoietin-2 (Ang2) is in the spotlight of studies for its unique role in modulating angiogenesis. The aim of this study was to introduce a computational simulation approach to screen aptamers with high binding ability for Ang2. We carried out computational simulations of aptamer-protein interactions by using ZDOCK and ZRANK functions in Discovery Studio 3.5 starting from the available information of aptamers generated through the systematic evolution of ligands by exponential enrichment (SELEX) in the literature. From the best of three aptamers on the basis of ZRANK scores, 189 sequences with two-point mutations were created and simulated with Ang2. Then, we used a surface plasmon resonance (SPR) biosensor to test 3 mutant sequences of high ZRANK scores along with a high and a low affinity binding sequence as reported in the literature. We found a selected RNA aptamer has a higher binding affinity and SPR response than a reported sequence with the highest affinity. This is the first study ofin silicoselection of aptamers against Ang2 by using the ZRANK scoring function, which should help to increase the efficiency of selecting aptamers with high target-binding ability.