bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanofiller Reinforced Polyolefin Elastomer: Effect on Morphology and Mechanical Properties of Composites
Authors: Pradhan Sharmila , Lach Ralf , Grellmann Wolfgang , Adhikari Rameshwar
Published: March 2013

The effect of different types of fillers on morphology and mechanical properties of polymer nanocomposites has been investigated using ethylene-1–octene copolymer (EOC), a polyolefin based elastomer, as matrix and various nanofillers {such as multi-walled carbon nanotubes (MWCNT), layered silicate (LS) and boehmite (OS2)}. The morphological structures were studied by scanning electron microscopy (SEM) while the mechanical properties were characterized by tensile testing and microindentation hardness measurements. It has been shown that the nature of the nanofiller may have significant influence on the mechanical properties of the samples. Among the nanocomposites studied so far, the MWCNT filled samples showed the highest reinforcing effect followed by layered silicate. The least reinforcing effect was obtained for the samples filled with boehmite nanoparticles. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 103-108 DOI: http://dx.doi.org/10.3126/njst.v13i2.7721
Adsorptive Removal of Toxic Metal from Aqueous Solution by Using a Biowaste -Used Tea Leaves
Authors: Shrestha Bindra , Homagai PL , Pokhrel Mr , Ghimire KN
Published: March 2013

In the present work an efficient and cost-effective biosorbent was prepared by chemical modification of tealeaves. Amine-functional group was introduced on the surface of adsorbent using dimethylamine. The adsorbent was characterized by SEM, FTIR and elemental analysis. The adsorption capacity of the adsorbent for Cd (II) was determined as the function of pH of the solution, concentration of metal ions and contact time. The maximum adsorption was found to be 77 mg/g at pH 6. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 109-114 DOI: http://dx.doi.org/10.3126/njst.v13i2.7722
Indentation Methods for Characterising the Mechanical and Fracture Behaviour of Polymer Nanocomposites
Authors: Lach Ralf , Kim Gyeong-Man , Adhikari Rameshwar , Michler Goerg H , Grellmann Wolfgang
Published: March 2013

Morphological analysis of nanocomposites of polyethylene glycol (PEG) based polyurethanes (TPU) and polyhedral oligomeric silsesquioxanes (POSS) were performed using different techniques (transmission electron microscopy, small and wide X-ray scattering, differential scanning calorimetry) as a function of molecular weight of PEG and the PEG/POSS mole ratio. A strong interdependence in crystallisation behaviour between the two crystals species, i.e. the POSS nanocrystals about 5 nm in size and the crystals in the semicrystalline soft phase of TPU, were found. The mechanical properties (Vickers hardness under load and elastic modulus) determined using recording microindentation techniques at room temperature were significantly improved by POSS for two material formulations. Based on the results of polymethylmethacrylate (PMMA)/silica (SiO2) nanocomposites containing up to 20 wt.-% well-dispersed spherical silica nanoparticles, it has been shown that the indentation fracture mechanics is a straightforward, costand time-effective, powerful tool to analyse the fracture resistance for the novel polymer materials, such as brittle nanostructured polymer-ceramic hybrids. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 115-122 DOI: http://dx.doi.org/10.3126/njst.v13i2.7723
Effect of Sediment Size in Hydraulic Turbine Material: A Case Study of Roshi Khola in Nepal
Authors: Poudel Laxman
Published: March 2013

Siltation problem in Nepal is major and challenging in hydropower development. It degrades the reservoir capacity and hydraulic turbines’ efficiency. Many researches have been carried out in this field and have proven sand as major substance that erodes the turbine material, but only few researches have accounted every parameters of sand on degradation of hydraulic turbines. This paper accounts size of sediments important parameter that has direct impact on turbine material. Sediment size impact has been studied firstly by characterizing size into six layered using sieve analyzer and testing its impact using high velocity test rig at Kathmandu University. Sand samples from 20 different stations of Roshi river were collected and tested on turbine material 18Cr4Ni. It found that greater micron sizes of sediments have great impact was than relatively smaller ones. It is depicted that 300-400 micron size sediment, have highest impact with weight loss of 0.022 milligram, 212-300 micron size has 0.013 milligram weight loss, 90-212 micron size has 0.012 and below 90 micron sizes have 0.0075 milligram of weight loss. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 129-132 DOI: http://dx.doi.org/10.3126/njst.v13i2.7725
Scientific Discourse of Lakes in Nepal
Authors: Bhuju DR , Sharma S , Jha PK , Gaire NP
Published: March 2013

Over 5,000 standing water bodies, including those <1 ha and spread in 74 districts of Nepal have been scanned on the topographic sheets (scale of 1:125,000). Majority of these lakes or ponds are either in the high altitudes (above 3,000 m) or in lowland Tarai (below 500 m). In a literature review we found over 163 research studies conducted since the first study of lakes in 1969 in Khumbu region, majority being at the initiative of national academia, their faculties and graduate students. However, a complete inventory of Nepal’s lakes is still lacking. Their characteristics and distinction from wetlands are also to be defined as the existing laws and rules do not protect lakes or ponds categorically, rather they are blanketed under wetlands and/or other river like water resources. Research observations have shown that acid depositions are the most likely source of pollution affecting high altitude lakes in the Himalayan regions during spring. Their value as religious sites has also caused anthropogenic alteration in nutrient concentrations and biological assemblages of the lake. Encroachment to the lakes/ponds is rampant to which the natural processes of sedimentation, alien species invasion or any kind of obliteration become supportive. Capacity building, knowledge generation and threat management are vital to protect these natural heritages from untimely demise. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 147-158 DOI: http://dx.doi.org/10.3126/njst.v13i2.7728
Multi-Drug and Pan-Drug Resistant Pseudomonas aeruginosa: A Challenge in Post- Antibiotic Era
Authors: Bhandari Shiva , Banjara Megha R , Lekhak Binod , Bhatta Dwij R , Regmi Shyam R
Published: March 2013

Clinicians still lack an appreciation of the potential importance of Pseudomonas aeruginosa (PA) in the hospitals. So this study was done in order to isolate and assess the prevalence of multi-drug resistant P. aeruginosa (MDRPA) and pan-drug resistant P. aeruginosa (PDRPA) from the intensive care units (ICUs). A cross-sectional study was conducted for six months at the ICUs of Shahid Gangalal National Heart Centre, Kathmandu. A total of 1,060 samples were processed out of which 700 were clinical samples directly taken from the admitted patients while 360 were the surface swab samples. The isolates were identified using routine conventional methods based upon microscopic findings, colony morphology and biochemical properties. Antibiotic susceptibility testing (AST) was performed by Kirby Bauer disc diffusion technique. P. aeruginosa was isolated from 66 (9.43%) clinical samples while 60 (16.67%) were surface swab samples. Among clinical isolates, 56 (84.8%) were sensitive to cefoparazone+sublactam (CSL) followed by 42 (63.6%) to polymixin-B and 36 (54.5%) to piperacillin-tazobactam (PT), while among surface swab sample isolates more than 90% were sensitive to most of the common antibiotics used. About 59 (89.4%) MDRPA were isolated from clinical samples while it was only 7 (11.7%) from surface swab samples. Only isolates from clinical samples (6.1%) yielded PDRPA. Since P. aeruginosa has shown the reduced susceptibility towards single antibiotics such as carbapenems, fluoroquinolones, aminoglycosides and cephalosporins, combined antibiotics like CSL and PT remained choice of treatment. This can eliminate potential threat of MDRPA and PDRPA in the ICUs. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 197-202 DOI: http://dx.doi.org/10.3126/njst.v13i2.7736
Virulence of Acinetobacter baumannii Exhibiting Phenotypic Heterogeneous Growth against Meropenem in a Murine Thigh Infection Model
Authors: Neou Evangelia , Michail George , Tsakris Athanassios , Pournaras Spyros
Published: March 2013

Acinetobacter baumannii may exhibit phenotypic heterogeneous growth under exposure to antibiotics. We investigated the in vitro characteristics of A. baumannii isolates grown heterogeneously in the presence of meropenem and their virulence evaluated in experimental infections treated with meropenem. Five clinical A. baumannii isolates and the respective heterogeneously grown subpopulations were tested by agar dilution minimum inhibitory concentration (MIC) testing, pulsed field gel electrophoresis (PFGE), population analysis using meropenem and growth curves. The virulence of isolates and the therapeutic efficacy of three meropenem dosing schemes was evaluated in a neutropenic murine thigh infection model. The clinical isolates were meropenem-susceptible (MICs 1 to 4 mg/liter) and exhibited three distinct PFGE patterns. In all clinical isolates, population analysis yielded heterogeneously grown colonies. After seven subcultures in antibiotic-free media, resistant MIC levels were retained in two isolates (heteroresistant), while three isolates were reversed to susceptible MICs (persisters). Clinical isolates and heterogeneous subpopulations had similar growth rates. The heterogeneously grown A. baumannii subpopulations had reduced virulence, killing considerably fewer animals than the respective clinical isolates without treatment. The meropenem treatment outcome was similar in infections caused by the clinical and the heterogeneous isolates, irrespective to their MICs. In vitro meropenem exposure induces phenotypic heterogeneous growth in A. baumannii. Compared with the parental clinical isolates, the heterogeneously grown subpopulations exhibited lower virulence, killing fewer mice and responding equally to meropenem treatment, despite their higher MICs.
Treading Old Paths in New Ways: Upper Secondary Students Using a Digital Tool of the Professional Historian
Authors: Nygren Thomas , Vikström Lotta
Published: March 2013

This article presents problems and possibilities associated with incorporating into history teaching a digital demographic database made for professional historians. We detect and discuss the outcome of how students in Swedish upper secondary schools respond to a teaching approach involving digitized registers comprising 19th century individuals and populations. Even though our results demonstrate that students experience the use of this digital database as messy, stressful, complicated, even meaningless and frustrating, they also perceive working with it as most interesting. We discuss this twofold outcome, its reasons and lessons to learn from it. When technology is functioning and the task is specialized and sufficiently guided by the teacher, which is not always the case, our results propose that digital databases can stimulate young people’s interest and historical thinking. Knowledge construction based upon historical thinking is evident in the students’ examination papers in which they present and debate their findings. These papers indicate that students can use a digital database and write history based upon empirical evidence, source criticism and historical empathy, just as professional historians do.
A New Algorithm for Identifying Possible Epidemic Sources with Application to the German Escherichia coli Outbreak
Authors: Buscema Massimo , Grossi Enzo , Bronstein Alvin , Lodwick Weldon , Asadi-Zeydabadi Masoud , Benzi Roberto , Newman Francis
Published: March 2013

In this paper we describe a recently developed algorithm called Topological Weighted Centroid (TWC). TWC takes locations of an event of interest and analyzes the possible associated dynamics using the ideas of free energy and entropy. This novel mathematical tool has been applied to a real world example, the epidemic outbreak caused by Escherichia coli that occurred in Germany in 2011, to point out the real source of the outbreak. Other four examples of application to other epidemic spreads are described: Chikungunya fever of 2007 in Italy; Foot and mouth disease of 1967 in England; Cholera of 1854 in London; and the Russian influenza of 1889–1890 in Sweden. Comparisons have been made with other already published algorithms: Rossmo Algorithm, NES, LVM, Mexican Prob. The TWC results are significantly superior in comparison with other algorithms according to four independent indexes: distance from the peak, sensitivity, specificity and searching area. They are consistent with the idea that the spread of infectious disease is not random but follows a progression based on inherent, but as yet undiscovered, mathematical laws. The TWC method could provide an additional powerful tool for the investigation of the early stages of an epidemic and novel simulation methods for understanding the process through which a disease is spread.
Structure-Based Search for New Inhibitors of Cholinesterases
Authors: Bajda Marek , Więckowska Anna , Hebda Michalina , Guzior Natalia , Sotriffer Christoph , Malawska Barbara
Published: March 2013

Cholinesterases are important biological targets responsible for regulation of cholinergic transmission, and their inhibitors are used for the treatment of Alzheimer’s disease. To design new cholinesterase inhibitors, of different structure-based design strategies was followed, including the modification of compounds from a previously developed library and a fragment-based design approach. This led to the selection of heterodimeric structures as potential inhibitors. Synthesis and biological evaluation of selected candidates confirmed that the designed compounds were acetylcholinesterase inhibitors with IC50 values in the mid-nanomolar to low micromolar range, and some of them were also butyrylcholinesterase inhibitors.
THz QCL-Based Cryogen-Free Spectrometer for in Situ Trace Gas Sensing
Authors: Consolino Luigi , Bartalini Saverio , Beere Harvey , Ritchie David , Vitiello Miriam , De Natale Paolo
Published: March 2013

We report on a set of high-sensitivity terahertz spectroscopy experiments making use of QCLs to detect rotational molecular transitions in the far-infrared. We demonstrate that using a compact and transportable cryogen-free setup, based on a quantum cascade laser in a closed-cycle Stirling cryostat, and pyroelectric detectors, a considerable improvement in sensitivity can be obtained by implementing a wavelength modulation spectroscopy technique. Indeed, we show that the sensitivity of methanol vapour detection can be improved by a factor ≈ 4 with respect to standard direct absorption approaches, offering perspectives for high sensitivity detection of a number of chemical compounds across the far-infrared spectral range.
« L'invention » de l'immigré. La psychiatrie belge face à la migration maghrébine dans les années 1960 et 1970
Authors: Majerus Benoît , Richel Julie
Published: March 2013

L’article croise histoire de l’immigration et histoire de la psychiatrie en s’intéressant à la façon dont une partie de la médecine a contribué à la fabrication de « l’immigré » en Belgique dans les années 1960-1970. À partir de dossiers médicaux, il montre que l’appréhension dominante s’est faite en termes culturalistes, le concept de culture servant de conceptcoupole qui permet d’articuler plusieurs différences difficilement appréhendables par les psychiatres. La culture peut servir pour analyser des rôles et des conflits interfamiliaux, expliquer les conflits entre pays d’émigration et pays d’immigration et exprimer l’incompréhension entre psychiatre et patient.
Coping Strategies for Child Bully-Victims
Authors: Buxton David , Potter Mona Patel , Bostic Jeff Q.
Published: March 2013

CME Educational Objectives

1.

Distinguish what types of bullying are most common at different ages.

2.

Describe six questions to screen for bullying and its effects.

3.

Identify three interventions for students and parents to address bullying, victimization, bystanding, and system rules that allow bullying.

Bullying affects most children in some way, as victims, bystanders, or bullies, during childhood. Children exposed to bullying may present with physical as well as psychological symptoms, and experience negative effects lasting into adulthood. This article provides information regarding bullying screening and interventions with pediatric and adolescent patients. Taking into account a child’s developmental stage, age-appropriate tactics are provided to address bullying, victimization, bystanding, and system “rules” that tolerate or foster bullying.
MULTIVARIATE TIME-VARYING AUTOREGRESSIVE MODELING OF FETAL SYMPATHO-VAGAL BALANCE THROUGH GESTATION
Authors: Gutiérrez D.
Published: March 2013

A processing framework is proposed to model relative changes in fetal sympatho-vagal balance at equally spaced gestational periods. The proposed method is based on a multivariable time-varying autoregression (TVAR) of the beat-to-beat time differences obtained from non-invasive fetal electrocardiographic (ECG) or magnetocardiographic (MCG) measurements. In order to quantify the sympatho-vagal balance at each measured gestational period, the ratio between the standard deviation of normal-to-normal (SDNN) beat intervals and the sum of absolute differences (SAD) is computed. While the SDNN quantifies the overall variability of the sympathetic and vagal systems, the SAD enhances short-term variability components related to vagal control, then the ratio of these two compares with high specificity the overall variability against the short-term vagal component in the time domain. The SDNN/SAD ratio is used to form a new data set by removing short-term variability events, then leaving only those corresponding to longer-term sympatho-vagal balance. The new data set is then analyzed as a dynamical system by fitting it to a suitable multivariate TVAR, and relative changes in the sympatho-vagal balance through the analyzed gestational periods are assumed to be related to the dynamics of the time-varying coefficients of the TVAR. In order to demonstrate the applicability of the proposed method, simulated and real fetal E/MCG data are analyzed. The results show that the modeling approach is able to infer the expected trend seen through sympatho-vagal development.
Study on the Intake Wind Performance Experiment of the Pipe with High Pressure Spray
Authors: Zhou Ai Ping , Wang De Sheng
Published: March 2013

By the intake wind performance experiment study of the pipe with high pressure spray, it is pointed out that under experimental conditions the intake wind efficiency of the pipe with high pressure spray is closely related to the spray nozzle and the pipe's structure and the size.The relationship between pipe's intake wind volume and spray nozzle's water consumption is linear, and the relationship between spraying spread angle and the hydraulic pressure becomes nonlinear.The main parameters of reducing dust equipment with high pressure spray is the intake wind volume and controlled zone.Under the conditions of certain structure, the adjustment of hydraulic pressure will make the equipment with high pressure spray run under the optimum condition of the highest intake wind efficiency.
A Study on Process of Modular Li-Ion Power Batteries
Authors: Liang Han , Feng Xiao , Li Yuan An
Published: March 2013

Li-ion power battery which has a broad prospect of application in many industry fields is a new type of high power battery. The formation-testing and sorting-packing are necessary processes in battery manufacture. Currently the process of formation almost takes the way of monomer battery, then sorting and packing by measuring the parameters of its internal resistance, voltage and capacity. The operation is complicated and the amount of data is huge. On account of the problem, we propose a new process of battery modularization. It can greatly reduce the workload of the parameter testing when using the optimized process. And batteries can get a good consistency, which is favor of sorting-packing and production automation.
The Virtual Prototype Design of the Micro Gear Box Mapping Stacker Base on Solid-Works
Authors: Feng Yan Sen , Hou Rong Guo , Li Zhi Yong , Zhao Guo Yong
Published: March 2013

The micro gearing box mapping stacker is designed based on the solid-works software. It aims to solve the difficulty of the micro gearing box mapping stacker, and the efficiency and mapping quality are greatly improved. The constitution of mechanism and working principle are emphasized here; the key mechanical transmission about the micro gear box mapping stacker is also designed ; the sending and mapping operation of the work-pieces are realized by the chain and synchronous belt transmission.
Research and Study of Gear Class Components Parametrization Based on AutoCAD
Authors: Li Jian
Published: March 2013

For achieved gear class parts of design calculation and drawing of automation, the paper proposed the parameterization design concept ideas, Using Auto-CAD Visual LISP language and Dialog control language (DCL) to design dialog box, realized parameters input with dialog through programmatic, and design and calculation of gear parts, parameters, proofing and gear designs drawn with different structures, output complete automation computer aided system
Analysis and Manufacture of Skew Bevel Gears with Spherical Involute
Authors: Wang Bai Chao , Zhang Guang Cheng , Yang Zhao Jun , Wang Yan Kun , Zhang Ya Qin , Tian Chun De
Published: March 2013

Skew bevel gears are fundamental element of transmission system. Processing quality of skew bevel gears has impact on the performance of system. An accurate processing method of tooth surface of skew bevel gears with spherical involute is proposed. According to the space meshing theory, the meshing equation of skew bevel gears is built by the theory of coordinate transform. And the generating principle of generation line of tooth surface about skew bevel gears is studied. In terms of the formation theory of tooth surface, moving process model of milling processing is established. And the generation line is as chord of face circular cutters to cut the tooth surface. Machining of the profile of skew bevel gears is performed using three axes linkage by the method. Finally, the transmission experiment proves that this method can improve dynamics and strength characteristics.
Starting Performance Analysis of Line-Start Permanent Magnet Synchronous Motor with Novel Rotor Structure
Authors: Xu Xiao Zhuo , Cui Ying Hua , Wang Xu Dong , Zhang Zan
Published: March 2013

A novel Line-start Permanent Magnet Synchronous Motor (LS-PMSM) with arc straight inserted permanent magnet is presented in this paper. The Simulink model is established according to voltage equation and motion equation, starting performance with rated voltage is calculated, performance on different voltages is also calculated, and the lowest voltage is obtained. Experimental facility is established. Influence of voltage on starting performance, such as electromagnetic torque, armature current, speed and slip ratio is analyzed by simulation and experimentation respectively. Results verify that good matching attributes are got. The foundation for widely industrial application of this LS-PMSM with novel rotor structure is found with performance research done above.
Research on Current Signal Acquisition of Soft-Start Controller
Authors: Guo Ji Hong , Li Li
Published: March 2013

To study of current signal acquisition circuit the mine explosion-proof and intrinsically safe type AC motor soft starter controller, which carries on AC sampling according to the soft start controller. the system adopts AC sampling method for sensor two information without any deformation processing, it is high-speed sampling. At the same time, the system uses root-mean-square algorithm to process AC signal and obtain the required current parameters. The experiment proves that this method enhances the overall system performance.
The Simulation and Realization Methods of Partial Discharge Signal in Gas Insulated Substation
Authors: Yun Yu Xin , Li Shi Peng , Li Ke Jun
Published: March 2013

On the basis of the analysis of simulating the partial discharge (PD) signals in Gas Insulated Substation (GIS), this paper focuses on discussing the common simulation and realization methods of simulating the partial discharge signals in mechanical and electrical equipments. The characteristics of PD signals and the typical insulation defects of GIS are reviewed. Different simulation methods to simulate the PD signals are considered. Two implementation schemes of simulating the discharge pulse are analyzed and compared with each other. Through the analysis, we find out that the electronic technology will be the most hopeful way to achieve the desired goals, which are to simulate those PD signals. This paper provides a simulation scheme of simulating PD signals, which can be described as multi-stage paralleling of MARX circuit and can provide a reliable reference for engineering practice.
Research and Design of One New Type of Satellite Antenna Unit
Authors: Zhang Hui Yong , Wang Li , Shi Ming Feng
Published: March 2013

antenna unit is the front end of the vehicle satellite, whether to the effective protection of the signal is received, the paper presents a novel microstrip antenna as a photonic crystal cyclical contour cylindrical air gap, and the shape of the radiation patch cutNotching of the ladder-type shape and has a good base slotted for a large number of experiments, simulation and optimization of the antenna with HFSS V12, results showed that the patch was "Asian" font, the highest performance antenna and the structure of the antennathe broadband resonant characteristics, the return loss is less than a 10 dB, impedance relative bandwidth of up to 47.1%, in a KU-band frequency range of the voltage standing wave ratio (less than VSWR <2), the relative bandwidth ratio reached 68.9%, significantly improved antennathe indicators.
Study on Preventing Override Trip System for High-Voltage Power Grid of Coal Mine Underground Based on the EtherCAT
Authors: Wang Yu Mei , Yang Xu , Zhang Hao
Published: March 2013

When the power supply system for coal mine underground take place a short circuit fault, multilevel switch often respond at the same time. And the existing comprehensive protector cannot satisfy the real-time and rapid quality requirements of preventing override trip system for high-voltage power grid of coal mine underground. So this paper put forward the research for comprehensive protector of preventing override trip based on the EtherCAT. This paper first analyzes the principle and characteristics of the EtherCAT technology; and then puts forward the overall scheme of preventing override trip system; Finally, study and design the slave station and master station of preventing override trip system based on the EtherCAT.
Adaptive Filter with Multiple-Scale Decomposition Rotor Broken Bars in Induction Fault Diagnosis
Authors: En De , Shi Xiao Long , Wei Huang He , Wei Na Na , Zhou Chang Sheng
Published: March 2013

There is a very small additional current component of frequency in the stator current signal when motor has broken rotor bars.So adaptive notch filter is applied to process the signals of the stator current in induction motors.The variable step size LMS algorithm and the multiple-scale wavelet transform are merged into the adaptive filtering system.A method is proposed, that is a LMS adaptive filtering algorithm with modified variable step size based on multiple-scale wavelet transform(MSWT-MVSS-LMS).It can eliminate interference from power frequency component to frequency component of broken rotor bar and achieve precise identification to frequency component of broken rotor bar from FFT.The result is a great help to extract the feature component of rotor fault and improve the sensitivity of fault diagnosis.The simulation show that the method is valid and effective.
Association between Genetic Polymorphisms of 5,10-Methylenetetrahydrofolate Reductase and Cytokinesis-Block Micronucleus in Peripheral Blood Lymphocyte among 1,3-Butadiene Workers
Authors: Liu Nan , Wang Xue Sheng , Cheng Juan , Xiao Jing Wei , Li Bin
Published: March 2013

Exploring the associations between genetic polymorphisms and susceptibility of chromosomal damage induced by 1,3-butadiene(BD) is of much importance for understanding BD carcinogenesis. In current study, we investigated the effects of MTHFR polymorphisms and MTHFR gene haplotype pairs on chromosome damage detected by the cytokinesis-block micronucleus (CBMN) assay in peripheral blood lymphocytes. The data showed that the frequencies of CBMN among BD-exposed workers were significantly associated with the MTHFR A1298C polymorphism (P=0.04 and P=0.03, respectively) by multivariate analysis of covariance. The foundings also showed that the haplotype pairs in the MTHFR gene were more likely than single SNPs to correlate with the BD-induced chromosome damage among occupational exposed workers. Gene-environment interactions between occupational BD exposure and polymorphisms of MTHFR were also evident. These results indicate that the MTHFR polymorphisms may play a role in sensitivity or genetic susceptibility in genotoxic effects of BD exposure in the occupational exposure population.
A Design of Carbon Oxide Sensor in Mine
Authors: An Wei Peng , Xing Lin
Published: March 2013

Monitoring of carbon monoxide gas is an important reference for the monitoring system, to provide protection for the personal safety of the miners. This paper introduces the AT89S52 [1] single-chip microcomputer as the core design of carbon monoxide sensor, realizes the carbon monoxide gas concentration detection. The sensitive head electrochemical sensing original hardware circuit by the amplifier circuit, A / D conversion circuit, display circuit, alarm circuit, an infrared receiving circuit, and the DS18B20 temperature sensor and other components. With real-time monitoring of carbon monoxide sensors, anti-jamming and real-time display function, and through the infrared circuit design makes the operation more convenient, higher accuracy.
Improved Vision-Based Algorithm for Unmanned Aerial Vehicles Autonomous Landing
Authors: Zhao Yun Ji , Pei Hai Long
Published: March 2013

In vision-based autonomous landing system of UAV (Unmanned Aerial Vehicle), the efficiency of object detection and tracking will directly affect the control system. An improved algorithm of SURF (Speed Up Robust Features) will resolve the problem which is inefficiency of the SURF algorithm in the autonomous landing system of UAV. The improved algorithm is composed of three steps: first, detect the region of the target using the Camshift algorithm; second, detect the feature points in the region of the above acquired using the SURF algorithm; third, do the matching between the template target and the region of target in frame. The results of experiments and theoretical analysis testify the efficiency of the algorithm.
Study on the Hardware Initialization of Embedded System
Authors: Liu Hua , Fan Ya Bin
Published: March 2013

An embedded system generally comprises of four parts (embedded microprocessor unit, peripheral hardware equipment, embedded operating system, and user application), and its core function is to complete the control of different equipments as well as necessary monitoring and management measures. Initialization is to set a variable as "default value", including system initialization, software initialization and hardware initialization. However, these three types of initialization are classified in accordance with different layers. This is studied in this paper.
CT Based Three Dimensional Geometric Model of Cervical Spine
Authors: Yan Zhi Yuan , Wu Dong Mei , Zhang Li Tao , Zhao Jun
Published: March 2013

In order to obtain high-quality analytical results of the finite element model, it is essential to construct a three dimensional geometric model. The paper reconstructed an accurate three dimensional geometric model of cervical spine segments (C4-C7). The process of reconstruction included three-dimensional reconstruction, smooth processing, contour generation, grid generation and fitting surface. Moreover, the result of reconstruction was evaluated ultimately. The model was validated to be smooth and reasonable, and could meet the requirements of finite element analysis. The method is not merely applied to reconstruct the geometric model of the cervical spine. It is a way to construct the model of the skeletal system of the human body.
Intelligent Shading Control System Based on the Lonworks Bus
Authors: Xiong Ai Min , Li Fei Yu , Xie Xuan
Published: March 2013

In order to improve the lighting and temperature control in large public buildings, intelligent shading technology has been growing attention. This intelligent shading control system is based on the Lonworks bus. It uses various sensors to detect indoor and outdoor light intensity and temperature changes automatically, the system provides reasonable the curtain control program to change the height of the curtains and the blade angle, to regulate indoor lighting and air-conditioning, reducing building energy consumption in all aspects. Common TCP / IP protocol is used to achieve a seamless connection with the building automation system. It concerns with energy saving, low carbon, environmental protection, intelligence concept of modern building.
The Fuzzy PID Control of Resistance Furnace Temperature System Based on Genetic Algorithm
Authors: Liu Jing Yan
Published: March 2013

The resistance furnace temperature system has low accuracy and big overshoots with fuzzy control. The fuzzy PID controller is used to optimize the resistance furnace temperature system, and the design scheme is developed. The fuzzy control and PID control are combined to control the system. If the system’s deviation is large the fuzzy control is adopted, else PID control is adopted. The genetic algorithm is adopted to train the controller’s membership functions, control rules and parameters. The global optimum of the controller’s parameters can be achieved. Matlab simulation results indicate that the resistance furnace temperature system with fuzzy PID control is more dynamic, robust, and highly precise.
Capacitance-Based Design of the Tap Water Flow Control Device
Authors: Zhang Ying Qi , Luo You Feng , Lin Ming Feng , Xiong Wei
Published: March 2013

In this paper, a capacitance-based design of the tap water flow control device is introduced. It is designed to prevent the waste of water resources caused by the current taps. It collects the capacitance signal by means of C/F conversion module based on 555 timer. Then the switching frequency signal and the flow frequency signal are generated according to the capacitance signal collected. They will be analyzed and compared with the signal STC15F100 microcontroller stored and generating the switch commands and flow regulation instructions to control the step motor. Finally, the water flow control function is realized by the device.
Indoor Open Spaces Precious Device Regulatory System Design Based on Internet of Things
Authors: Yu Zhang Hong , Jian Yu Qing , Liu Shu Rong , Cao Li Jun
Published: March 2013

To study the design of the indoor open places precious device regulatory system based on Internet of Things, the system uses a star structure, with intelligent alarm control center, using distributed monitoring terminal, automatic detection of invasive behavior in arming monitoring area, the alarm signal is generated. Alarm control center of the system is mainly based on the ARM processor core hardware platform and embedded Linux operating system development; monitoring terminal use the SOC chip CC2530-core hardware platform; Zigbee wireless transmission technology is used to communicate between the control center and monitor terminal.
Research of Robocop Simulation Platform for Robot Soccer
Authors: Zhong Guang Yang
Published: March 2013

With the development of computer technology, Multi-Agent System of Distributed Artificial Intelligent is advanced and implemented. This paper discusses the method for realizing the offences and defences of intelligent robot in Robocop simulate competition.
Simulation of Vehicle Dynamic Stability on Ro-Ro Ship Using MHS Measurement
Authors: Zhao Ding Xuan , Zhao Ying , Hou Jing Wei
Published: March 2013

By modeling ship motion using PM wave spectrum and strip theory, and modeling vehicle as rigid chassis and flexible tire, the dynamics equation of ship and vehicle multi-body system is developed using Lagrange equation. The numerical solution of equation shows the forces between tire and deck contact are impacted by ship motion. To compare the possibility of tip over around different axes, a Moment-Height Stability (MHS) measure method is used to calculate the stability of vehicle on the deck. The MHS result shows compartments of the instability around each edge, which is a good supplement to the tire force method.
Effects of Masonry Infills on Seismic Response of Steel Structures
Authors: Valente Marco
Published: March 2013

The effects of masonry infills on the seismic performance of a multi-story steel frame building were investigated through nonlinear static and dynamic analyses. Three variants of masonry infills, aimed at simulating weak, intermediate and strong infill panels, and the presence of masonry openings were considered in the numerical analyses. Strong masonry infills significantly contributed to the lateral stiffness and load resistance of the steel structure, but a sudden decrease of strength was observed after the failure of infills. This phenomenon was less evident in presence of openings. The results of the nonlinear dynamic analyses confirmed the satisfactory performance of masonry infilled steel structures under the design earthquake intensity. The presence and the mechanical properties of the infills affected the distribution of damage throughout the structure. The maximum inter-story drift occurred at the third level for the bare structure, whereas in the structures infilled by strong masonry panels the maximum inter-story drift was registered at the first level.
The Research of Impact Ball End Mills Geometric Parameters on Processing Stable Region
Authors: Jia Dong Kai , Xiao Fei , Wu Shi
Published: March 2013

In this paper, modal analysis of ball end mills is modeled by finite element to work out natural frequency and chatter model in tooling system and to calculate the limit curve of stability in single degree freedom system. The effect of cutter flute length and cutter tooth number on maching stability area is also discussed. The results of research show that steady critical cutting depth of milling system declines while the cutter flute length increases, but the trend is not linear, which shows increase partly. An engineering optimization design is made on milling cutter geometrical parameters based on this conclusion.
Research on the Friction Mechanism and Minimum Steady Speed of Electro-Hydraulic Servo Motor
Authors: Wang Xiao Jing , Cui Xiao , Li Ping , Chen Xin , Xiu Li Wei
Published: March 2013

The super low speed performance of continuous rotary motor is the key performance, many factors influence the super low speed performance, such as friction and leakage characteristics of the motor, pressure impact, pressure fluctuation of the oil source, resolution and the dead zone of the servo valve. This paper study the low speed movement mechanism, by analyzing the friction mechanism model of motor, and analyze the low-speed process the system to explore the factors that affect the low-speed performance of system, and determine the lowest steady speed of motor.
Optimal Classification of Hypersonic Inlet Start/Unstart Based on Manifold Learning
Authors: Zheng Ri Sheng , Chang Jun Tao , He Hui Xin , Chen Fu
Published: March 2013

Inlet start/unstart detection has been the focus of researching hypersonic inlet, the operation mode of the inlet detection is the prerequisite for the unstart protection control of scramjet. Actually, due to computational complexity and high dimension discrete experimental data, all of these factors are against for the classification of real-time data. To solve this problem, firstly, the 2-D wind tunnel experiment is carried out, inlet start/unstart experiment phenomenon are analyzed; Secondly, isomap algorithm is introduced to reduce high dimensional data , the optimal classification method were obtained with the weighted embedded manifold learning algorithm, At last the superiority of the classification criterion is verified by decision tree algorithm.
Design of the Intelligent Vehicle System Based on CCD Camera
Authors: Wang Ye Qin
Published: March 2013

In the context of the session of the freescale Intelligence Car Competition, this paper designed the intelligent vehicle system based on MC9S12XS128 microcontroller and its mechanical system considering the driving-stability and comfort of car module. In the system, CCD camera gathers real-time track road conditions information, and then the microcontroller will identify road situation and realize tracking control with these information. Using time-optimal to control the DC motor speed and the positional PID to control the steering gear, adjust PID parameters dynamically based on the position of the black line. These measures guarantee the intelligent vehicle travel along a specified route safely、smoothly and fast, and then realize automatic tracing. The results show that the system meets the need of path recognition and anti-interfere well.
Hardware Design for Electric Locomotive Anti-Collision Warning System Based on AT89C52
Authors: Wang Ye Qin
Published: March 2013

To avoid safety hazards in the mine electric locomotive transporting, designed an anti-collision warning system for electric locomotive. The system took MCU AT89C52 as core controller, including ranging module, speed measuring module, display module, warning module and anti-interference design. The system used ultrasonic sensor and incremental rotary encoder respectively to measure distance and velocity, and then obtained the distance and velocity data through MCU AT89C52. Through analyzing these data, the system can alarm and stop the locomotive, and then ensure the safety of locomotive and workers. Therefore, the system has a very good market prospect.
The Design of Yarn Constant Tension Feeder System
Authors: Zhou Mei Lan , Fu Yan Hui , He Zhen Qiu , Liu Rui
Published: March 2013

A novel constant tension yarn feed control system for automatic winder is presented in this paper which is based on analyzing the principle of the generation of yarn tension and the factors which make the tension fluctuate. DSP28035 made by TI (Texas Instruments) is adopted as the main control unit of the system to acquire the real-time yarn tension which is transmitted from a yarn tension sensor. Intelligent PID (proportional-integral-derivative) algorithm is also adopted to achieve a high-dynamic performance and an ultra-low inertia servo motor speed digital control to realize constant yarn tension feed. The system not only have the function of tension setting, over current protection, error detection and alarm, but also possess the features of simple structure, low cost, real-time control and high accuracy.
The Method of Multiple Scales in Solving Nonlinear Dynamic Differential Equations of Gear Systems
Authors: Nie J.F. , Zheng M.L. , Yu G.B. , Wen J.M. , Dai B.
Published: March 2013

To obtain exact analytical solutions of differential equations of gear system dynamics due to the difficulty of solving complicated differential equations. Only the approximate analytical solutions can be determined. The method of multiple scales is one of the most powerful, popular perturbation methods. The dynamic model which describes the torsional vibration behaviors of gear system has been introduced accurately in this paper. The differential equation of gear system nonlinear dynamics exhibiting combined nonlinearity influence such as time-varying stiffness, tooth backlash and dynamic transmission error (DTE) has been proposed. The theory of multiple scales method has been presented in solving nonlinear differential equations of gear systems and the frequency response equation has been obtained. The fact that the approximate analytical solution by using the method of multiple scales is in good agreement with the exact solutions by numerically integrating differential equations has proved that the method of multiple scales is one of the most frequently used methods in solving differential equations, especially for large and complicated differential equations.
Design of BLDCM Fuzzy Control System for Electric Vehicle Based on DSP
Authors: Wen Jia Bin , Yang Bin
Published: March 2013

In this paper, the design of BLDCM fuzzy control system for electric vehicle which bases on TMS320F2812 Digital Signal Processor (DSP) is given. The design methods of hardware and software of the control system are described in details. Using of brushless DC motor current and speed double closed loop control, meanwhile, the fuzzy self-tuning PI algorithm is applied in the control system, and achieve the intelligent control of brushless DC motor control system. In this paper, the PWM control of the overlapping commutation method to suppress torque ripple. Experimental results show that this system has such characteristics as sound controlling effects, obvious restrain of torque pulsation and reliable operation.
Investigation of Compressive Damage Mechanisms in 3D Braided Composites by the Acoustic Emission Events Energy and Amplitude
Authors: Yan Shi , Pan Shi Dong , Li Dong Hua , Feng Ji Cai
Published: March 2013

The deformation behavior and damage mechanism of 3-D carbon/epoxy braided composites with different braiding angles under the monotonic compressive loading are investigated by the acoustic emission (AE) technique. The damage process is divided into several different regions based on the change of the accumulative AE event counts. Correlations between the damage mechanisms and the AE results are established in terms of the events energy and amplitude. These correlations can be used to monitor the fracture growth process in the braided composites. Experimental results reveal that the AE technique is an effective tool for identifying damage mechanisms.
Preparation and Characterization of ZnO: Eu, Mn Luminous Material
Authors: Ye Ya Nan , Dong Li Min , Che Hou Zhao , Mao Shuai Ying , Chen Zi Yi , Zhang Xian You
Published: March 2013

Chemical precipitation method was used to prepare phosphors ZnO: Eu2+ and Mn2+ (urea as a precipitating agent, ZnO as a substrate and Eu, Mn as doping elements). A series of preparations with different composition and sintering temperature were characterized by scanning electron microscope (SEM), thermal gravimetric analysis (TG-DTA), x-ray powder diffraction (XRD) and fluorescence spectrophotometer respectively, and the nano-particle characteristics and luminescence properties of the product were studied in detail. The results showed that the size of the nano-particle was uniform (with a narrow distribution), and the fluorescence mechanism would not change when Eu and Mn were doped in the ZnO matrix to prepare luminescence material, it was a feasible way to reduce the damage to the environment and further to explore the ZnO phosphor technology and the application of light-emitting.change when Eu and Mn were doped in the ZnO matrix to prepare luminescence material, it was a feasible way to reduce the damage to the environment and further to explore the ZnO phosphor technology and the application of light-emitting.