bluuebunny/crossref_metadata_2025 huggingface dataset:
A Coordinated Volt/Var Control Strategy for Wind Farm Group
Authors: Sun Jian , Wang Qiang , Yang Yang
Published: December 2014

A coordinated Volt / Var control strategy for wind farm group is proposed. The area voltage control center monitors the pilot bus in the central substation where many wind farms are connected to, and coordinates all kinds of reactive power resources in different wind farms to regulate the voltage profile of all wind farms. The genetic algorithm is used to solve such a multi-objective optimization model. The simulation results of a typical wind power system show that the coordinated control strategy has better performance than the current individual one in respects of security and economy of the grid.
Design and Analysis of Steering Mechanism for Small Tracked Vehicle
Authors: Zhou Fa Liang , Xu Xiao Jun , Zhang Hao Yue
Published: December 2014

The steering mechanism of tracked vehicles is complicated and large, which is an obstacle for its miniaturization. According to the theory of rubber-belt CVTs, a new kind of steering mechanism for small Tracked vehicle is designed. The mechanism consists of two symmetrical-layout rubber-belt CVTs. A sliding part for steering is designed, which can slide axially to make the transmission ratio of one transmission increase while the other reduces, so that the tracked vehicle turns. The steering motion is calculated and its motion discipline is founded. The steering sensitivity and steering smoothness are analyzed, and its steering performance is evaluated.
Software Defect Distribution Prediction for BOSS System
Authors: Han Wan Jiang , Jiang He Yang , Sun Yi , Lu Tian Bo
Published: December 2014

Effective detection of software defects is an important activity of software development process. In this paper, we propose an approach to predict residual defects for BOSS project, which applies defect distribution model. Experiment results show that this approach can effectively improve the accuracy of defect prediction.
Design of Transverse Boom-Type Roadheader Remote Control System
Authors: Wang Xiao Dong , Shi Ming Quan , Gao Shu Jun , Guo Yang Chen
Published: December 2014

The roadheader remote control system is proposed to protect operator away from the dust and the danger on working site, improve the operator's labor environment, reduce personal injury accidents, and enhance the security of mining operations. The cutting head and spade board position of transverse boom-type roadheader were analyzed. The mathematical models of cutting head vertical swing, cutting head gyration swing and spade board vertical swing were established. Geometric relationship between the angle and the stroke of hydraulic cylinder of cutting head and spade board were calculated. Finally, based on programmable logic controller (PLC) and industrial personal computer (IPC), the remote control system was designed and the automatic cutting method was proposed. The roadheader remote control system had been applied successfully in EBH132 roadheader. The system significantly enhances the efficiency and security of the main production.
Development of Intelligent Frequency Drum Washing Machine Based on Fuzzy Control Technology
Authors: Lin Li Zong , Chen Jian Feng , Han Shuai , Huang Chao , Ke Zi Li
Published: December 2014

Aiming at the current energy efficiency of washing machine is not high. The smart inverter washing machine based on fuzzy control technology is designed. Drum washing machine including a content body structure design, programmable controller and the overall program and frequency control module is highlighted. And the generation and fuzzy reasoning process SPWM signals and other issues are discussed in detail. The results show that the use of fuzzy control technology frequency control can not only save water and energy, but also meet the modern requirements of a variety of special laundry, in line with the development trend of the washing machine technology.
Implementation of Intelligent Control System for Autonomous Underwater Vehicle
Authors: Pshikhopov Viacheslav , Chernukhin Yuriy , Guzik Viktor , Medvedev Mikhail , Gurenko Boris , Piavchenko Alexey , Saprikin Roman , Pereversev Vladimir , Krukhmalev Victor
Published: December 2014

This paper introduces the implementation of intelligent motion control and planning for autonomous underwater vehicle (AUV). Previously developed control system features intelligent motion control and planning subsystem, based on artificial neural networks. It allows detecting and avoiding moving obstacles in front of the AUV. The motion control subsystem uses position-trajectory control method to position AUV, move from point to point and along given path with given speed. Control system was tested in the multi-module simulation complex. Simulation showed good results – AUV successfully achieved given goals avoiding collisions not only with static obstacles, but also with mobile ones. That allows using the proposed control system for the groups of vehicles. Besides simulation, control system was implemented in hardware. AUV prototype passed tests in Azov Sea and proved its efficiency.
Station Deployment of Workspace Measuring and Positioning System Based on Multi-Objective Genetic Algorithm
Authors: Yue Chong , Xiong Zhi , Fan Yi Yan
Published: December 2014

Workspace measuring and positioning system (wMPS) is a kind of large-scale and multi-station intersection system, of which the station layout optimization is a common but important problem. Station optimal topological geometry based on genetic algorithm was proposed in this paper. Firstly, the positioning error, coverage area and cost were taken as objectives to establish the multi-objective optimization function. Secondly, genetic algorithm optimization process was established according to multi-objective function. Thirdly, simulation analysis for layout optimization algorithm of 2-4 stations was performed. The results show that the proposed method is able to quickly converge to optimal solutions, have good adaptability and improve wMPS measuring performance as well.
Mechanical Structure and Obstacle-Navigation Simulation Analysis of Inspection Robot with Four Arms Based on Virtual Prototype Technology
Authors: Wang Ji Dai , Wang Jing , Wei Jun Ying
Published: December 2014

Power line inspection especially the super-high voltage four splitting transmission line inspection is of the utmost importance for the reliability and stability of electric power system. Making use of the robot technology to inspect has been a research hotspot in recent years due to its complicated geographical distribution environment. According to the characteristics of the transmission lines and inspection requirements, mechanical structure composition of a new inspection robot with four arms was firstly introduced in this paper. Based on this, the kinematics simulation and movement of the obstacle-navigation process was analyzed by ADAMS. The experiments about obstacle-navigation and climbing ability had also been conducted. Through repeated simulation and experiments, it has been verified that the robot proposed can cross obstacles smoothly, and have the advantages of high efficiency and strong climbing ability, which has great development and application potential.
Modeling and Simulation Research of Time-Dependent Reliability Model of Tooth Carrier in Feed Mechanism
Authors: Gong Yan Jue , Zhao Fu , Xin Hong Bing , Xiang Hui Yu , Meng Chun Ling , Zhang Yuan
Published: December 2014

The time-dependent reliability model of Mechanical Component is influenced by many parameters such as stress, load, strength, strength degeneration and lifetime index. This paper builds the time-dependent reliability model when life is measured by the loading numbers. The variety law of mechanical component’s reliability with the lifetime is derived from the built model and simulation of tooth carrier in feed mechanism used in the sewing machine. The result shows that the time-dependent reliability model is effective and the reliability of component decreases obviously with the loading numbers when the strength degeneration is considered.
Research on LSM with Permanent Magnet Halbach and Ironless Coil for Magnetic Levitation Vehicles
Authors: Zhang Xiao , Lu Jun Yong , Long Xin Lin
Published: December 2014

In this paper, a kind of Linear Synchronous Motor (LSM) with Permanent Magnet (PM) arranged in Halbach array and IronLess Coil (PMH&ILC) is presented for Magnetic Levitation Vehicles (Maglev). First, the propulsion force of this kind of LSM is deduced analytically. Then, the influences of pole spacing, the current in the coil, the width of the motor and the size of the Halbach array on the propulsion force are analyzed mathematically in detail. Based on the results, the design method and basic principle of PMH&ILC-typed LSM are proposed, which shows a better performance with small pole spacing, higher permanent magnet array, optimal value of the width of the permanent magnet Halbach and so on. Finally, a sample LSM system is designed according to the requirements of Maglev propulsion system.
The Parameter Identification and Error Compensation of Robot Based on Dynacal System
Authors: Qi Fei , Ping Xue Liang , Liu Jie , Jiang Yi
Published: December 2014

According to the robot positioning accuracy, this paper proposed an error compensation method after updating the controller parameters based on the D-H parameters model and Dynacal system. The proposed method is effectiveand was validated on the developed robot of which the mean error was reduced to 0.092mm. The method can greatly improve the positioning accuracy of the robot.
The Steering Performance Analysis of Multi-Axle Vehicle Based on Sideslip Angle Control Strategy
Authors: Zhang Ping Xia , Gao Li , Zhu Yong Qiang
Published: December 2014

Because there are several axles in multi-axle vehicle, steering controlling is very complex. It is proposed to use the front wheel steering angle and D as input controlling variables, and to realize centroid sideslip angle control. A five-axle vehicle model was built with ADAMS software, and the control strategy was built with Simulink software. The steering angle step response simulations were processed, such as only font wheels steering, fixed D value steering, and different sideslip angle control strategy. It is found that for only font wheels steering test, variable sideslip angle control strategy could make the overshoot of yaw rate reduce from 98% to 10%, convergence time reduce to 57%.
Research on Multidimensional Liquid Chromatography Sample Pretreatment System
Authors: Wang Peng , Cai Jun , Li Dong Hao , Piao Xiang Fan
Published: December 2014

Using multidimensional liquid chromatography technology, a liquid chromatography sample pretreatment system which was controlled by a microcontroller was designed. Real sample pretreatment experiments have been done. The experimental results showed that the complex samples can be separated effectively with this system according to 3 polarities. The operation of this system is simple, fast and high automatic, which meet the requirements of pretreatment of liquid chromatography complex samples.
Comparative Study on New Methods of Tubing Cleaning
Authors: Yang Zhong Guo , Wang Zun Ce
Published: December 2014

This paper expounds the concept and application of tubing flushing, and compares different methods of new tubing cleaning for the equipment and process technology, such as the electromagnetic induction heating oil pipe cleaning, far infrared preheating washing, high-pressure water jet flushing and high efficient heating oil pipe scouring, so the theoretical result can provide guidance for the work.
Discussion on NC Machining Process of Thin Walled Parts Technical Measures
Authors: Zhang Da Lin , Gao Ke , Zhou Tian Rui
Published: December 2014

Thin wall parts are used more and more extensively in industrial production, analyze the influence of precision machining of thin-walled parts not higher factor, through the example of how to improve the machining precision of thin-wall parts, and gives the specific measures to solve practical problems.
Study on Axial Oil Chamber Design for High Performance Hydrostatic Spindle
Authors: Chen Shao Hsien , Chen Shang Te , Hsu Chien Cheng
Published: December 2014

Ultra-precision machining and large-size equipments are themostprimary development trend ofcurrentmachine tooland hydrostatic products arekeytechnologiesof ultra-precision machining equipments. However, these equipmentsmostlyprocess miniature components, thus the adopted tools are relatively small and the spindlesare mainlybuilt-in types of HSK32-HSK25 withover30,000r. Some processing equipments are even equipped with hydrostatic or gas-static spindles. The studyextends theaxialoilchamberto radialonesto expand theaction areaofaxialoil pressureand form a closed oil seal edge by combining theradialclearance. Consequently, theaxialbearing stiffnesscan be enhancedtoenlarge the application scope of hydrostatic spindle. The designmodecan enhanceaxialstiffness ofspindle modulesor strengthenthe stiffness of hydrostatic spindlein a ball screw.
Numerical Simulation on Soil Arch Effect and Load Reduction Mechanism Using EPS of High Fill Culvert
Authors: Chen Bao Guo , Jiao Jun Jie , Song Ding Bao , Zhang Jun
Published: December 2014

The stress-strain relationship of EPS board was analyzed. Theoretical analysis and numerical simulation (FE ABAQUS) were conducted to investigate the load reduction mechanism using EPS and soil arch effect of high fill culvert based on the constitutive relation of EPS board. The results show that the numerical analysis results are consistent with the theory analysis. It shows that the soil arch forms over the culvert top and partial weight of the soil column exactly over the culvert has been transferred to the outer soil column via the soil arch during the yield stage of EPS board, which produce large deformation. Furthermore, the numerical simulation by using particle flow discrete element software (PFC2D) was conducted to investigate the soil arch effect over the culvert top. The research reveals that the EPS board is at elastic state and the soil arch effect on culvert top is not obvious at low fill. With the increasing of the fill over the culvert, the EPS board becomes into the yield state, the soil arch effect over the culvert increases and the earth pressure on culvert reduces gradually.
A Novel and Practical Method for Network Security Situation Prediction
Authors: He Gao Feng , Zhang Tao , Ma Yuan Yuan , Guan Xiao Juan
Published: December 2014

The real-time prediction of network security situation can significantly improve the monitoring and emergency response capability of the network. However, in practice, if there are a large amount of false predictions, the network administrators should become insensitive and will finally ignore all prediction results. In this paper, we try to solve this issue and propose a novel False Positive Adaptive (FPA) method for network security situation prediction. The main idea of our method is using extrainformation to reduce the number of false positives in prediction. In the model training step, we take advantage of host and network information to eliminate meaningless alerts produced by security tools such as Intrusion Detection System (IDS) and firewall, thus assuring the accuracy of the training samples. In the prediction step, we utilize the detection information from security tools to confirm the prediction results automatically. If the previous predictions are not detected, they will be considered as false positives and the prediction model will be retrained by incremental learning. In our work, the model training and incremental learning is accomplished efficiently by neural network and boosting algorithm.
A Novel File Hierarchy Access Control Scheme Using Attribute-Based Encryption
Authors: Wang Shu Lan , Yu Jian Ping , Zhang Peng , Wang Ping
Published: December 2014

Attribute-based encryption (ABE) can keep data privacy and realize fine-grained access control. However, the notion of file hierarchy hasn't been presented until now. The problem, the multiple hierarchical files to be shared only using once encryption scheme, cannot be effectively solved. Based on the access structure layered model, a novel access control scheme about file hierarchy is proposed by using ABE to solve the problem. The proposed scheme will not only decrease the number of access structures to one, but also only require a secret key to decrypt all the authorization files. It is proved to be secure against the chosen-plaintext attack (CPA) under the decision bilinear Diffie-Hellman (DBDH) assumption. In addition, the performance analysis results indicate that the proposed scheme is efficient and practical when a large number of hierarchical files are shared.
A Two-Layer Hybrid Trust Mechanism Based on Agent Trust
Authors: Ye Jian Wei , Jiao Xu Lu , Xu Zhi Kai
Published: December 2014

Trust is the foundation of all kinds of Internet activity. As a more open resource sharing model, cloud computing environment consists of mass resource owners and users belonged to different control domain. Therefore, the establishment of the trust relationship among the participants and the guarantee of security and efficiency in the computing process are one of the most fundamental problems of cloud computing security. This paper proposes a two-Layer hybrid trust mechanism based on agent trust. In my proposition, trust relationship is relayed and secure computing environment is established among the different participants by the various existing trust methods.
An APT Trojan Detection Method Based on Memory Forensics Techniques
Authors: Wang Lian Hai , Xu Qiu Liang
Published: December 2014

Advanced Persistent Threat (APT) is currently reported to be one of the most serious threats. It is very important to detect the APT Trojan as early as possible. There are three types of approaches to conduct APT detection: network traffic analysis, change controlling and sandboxing. Unfortunately, all these approaches have limitations in detecting unknown APT Trojans. This paper proposes a novel APT Trojan detection method by utilizing memory forensics techniques. The proposed method first acquires the raw physical memory image from a target running system and then finds the APT’s traces in the memory image based on the ATP’s characteristics and memory forensics techniques. If enough traces are found, we can judge that there must be Trojans in the target system. Experimental results show that the proposed method can effectively detect new APT Trojans.
An Information Real-Time Transmission Algorithm Based on the Android Platform
Authors: Hong Nian Fang
Published: December 2014

In the wireless network environment, a large number of applications based on cell phone have emerged. But it has appeared some problems such as large amount of data and limited bandwidth and higher quality transmission in the mobile streaming media data transmission. To solve these problems, this paper designs a bandwidth adaptive streaming media real-time synchronization algorithm. Algorithm firstly analysis the state of the network, and then through real-time increase or decrease the factor method to effectively adjust the code flow rate, thus improve the QoS of streaming in transmission; to meet the learners' online learning, for subsequent teaching and interaction provides a good technical support.
An Integrated Electricity Information Security Monitoring Platform
Authors: Yu Ran , Zhang Jiao Jiao , Xu Hong Fei , Jin Shen
Published: December 2014

An integrated electricity information security monitoring platform is presented, electrical information security integrated real-time monitoring of the state power applied information security systems, security equipment, network equipment, network boundaries, desktop computers, to improve information security monitoring, early warning, emergency response and defense capabilities to protect IT hardware, software and network security, which can guarantee continuous, reliable and efficient operation.
Building of Cloud Computing in University Employment Information Library
Authors: Liu Chong
Published: December 2014

Cloud computing is a product of the development of the Internet of things, so it has the characteristics as the network does, namely dynamic, patulous and virtual. This paper studies the use of cloud computing in university employment information library. By understanding the definition, application characteristics and advantages of cloud computing, and considering the opportunities and challenges which we face in the issue of employment of college graduates, we try to dig deeper into the relationship between companies and graduates in order to build a "cloud" of labor market information, namely cloud computing database. The results show that with cloud computing we can fully meet the company by find the required graduates faster. Students can also find suitable jobs easier.
Dynamic Deploy Based on Honeynet
Authors: Li Wen Yong
Published: December 2014

This paper propose an idea of dynamic deploy and relevant algorithms. The first step of dynamic deployment is that it will forecast the security situation through grey forecast model. Then, the virtual honeypots will be changed by imitating the biology actions. Hence, the dynamic Honeynet has the ability of disguising according to the realtime intrusion. It improves the effect in confusing hackers and weakens the attack. The model and relevant algorithms are presented. The results of experiment show that dynamic deploy scheme better effect in deceiving hackers with lower cost compared to the static deploy scheme.
Reliability of Multiple-Stage Cascaded Passive Optical Networks: A Perspective
Authors: Gao Ge Jun , Li Xun Jie , Tao Shuai , Shen Jian Hua
Published: December 2014

Passive Optical Network (PON) technology has been widely accepted as main broadband access which can satisfy the rapid increasing bandwidth requirements. With the expansion of the number of users, as well as the variation of application scenarios, traditional single-stage cascaded or two-stage cascaded PON system can no longer meet users’ demands. This paper proposed four multiple-stage cascaded PON topologies with different protection schemes. Reliability and cost for each topology are presented with theoretical analysis and numerical simulations.
In Vitro Antioxidant Activity of Electrospun Chitosan Aqueous Salts Based Nanofiber Mats
Authors: Charernsriwilaiwat Natthan , Rojanarata Theerasak , Ngawhirunpat Tanasait , Opanasopit Praneet
Published: December 2014

The aim of this study was to investigate the antioxidant activities of chitosan acetate (CS-acetate), chitosan hydroxybenzotriazole (CS-HOBt), chitosan thiamine pyrophosphate (CS-TPP) and chitosan ethylenediaminetetraacetic acid (CS-EDTA) nanofiber mats. Chitosan was dissolved with hydroxybenzotriazole (HOBt), thiamine pyrophosphate (TPP) and ethylenediaminetetraacetic acid (EDTA) in distilled water. These chitosan aqueous salts were blended with polyvinyl alcohol (PVA) at volume ratio 30/70 chitosan salts/PVA and prepared to nanofibers via electrospinning process. The morphology of electrospun chitosan aqueous salts based nanofiber mats were observed under scanning electron microscope (SEM). The antioxidant activities were determined employing various established in vitro system such as superoxide, hydroxyl radicals scavenging and metal ion chelating compared with pure PVA nanofiber mats. The results exhibited that the electrospun chitosan aqueous salts based nanofiber mats showed the different antioxidant activity depended on salt forms. Among the salt forms, CS-acetate nanofiber mats showed the highest superoxide radical scavenging effect while CS-HOBt nanofiber mats (IC50 = 7.53 mg/mL) showed the highest hydroxyl radical scavenging effect. For the metal ion chelating activity, CS-EDTA nanofiber mats showed the highest chelating activity (IC50 = 1.07 mg/mL). In summary, the antioxidant chitosan aqueous salt based nanofiber mats have potential for use in pharmaceutical applications.
Enhanced Mechanical Properties of Shellac Films by Incorporation of Modified Coconut Oil
Authors: Sittipaisankul Potchaman , Luangtana-Anan Manee , Limmatvapirat Chutima , Limmatvapirat Sontaya
Published: December 2014

The purpose of this study was to evaluate the effect of modified coconut oil (MCO) on elasticity change of films prepared from shellac. The MCO was added into shellac solution and then cast to thin film. The film containing MCO from 0-30% w/w was then comparatively evaluated. The result indicated that MCO had an direct effect on mechanical properties of films. The percentage elongation was increased while the tensile strength was decreased, as increasing percentage of MCO, suggesting the reduced brittleness of film. The FTIR peak assigned to O-H and C-O stretching was also shift after incorporation of MCO. Therefore, the plasticization of shellac film might due to the interaction between hydroxyl group of glycerides in MCO and shellac molecules.
Effect of Glycerol on Properties of Tapioca Starch-Based Films
Authors: Piyawatakarn Piyapoom , Limmatvapirat Chutima , Sriamornsak Pornsak , Luangtana-Anan Manee , Nunthanid Jurairat , Limmatvapirat Sontaya
Published: December 2014

The aim of study was to determine the effect of glycerol on the properties of tapioca starch films. The films containing various amounts of glycerol (0-30 %w/w) were prepared by casting method. Texture analyzer, x-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) were used to comparatively characterize the films. The result indicated that mechanical properties were depended on amount of incorporated glycerol. The films containing 0-10 %w/w of glycerol showed brittle characteristic while those containing 20-30 %w/w demonstrated elastic film, suggesting the plasticization effect of glycerol. As indicated by x-ray diffractometry, the crystallinity was increased as increasing percentage of glycerol. The 3D structural change after incorporation of glycerol in polymer chain of starch might affect the properties of films. However, the FTIR spectra did not show clear interaction between glycerol and starch. The physical entrapment of glycerol in amylose chain might be a possible explanation for the results.
Comparison of In Vitro Binding of Various Bile Salts by Coconut Fibers
Authors: Sriamornsak Pornsak , Limmatvapirat Sontaya , Asavapichayont Panida , Konthong Srisuda
Published: December 2014

The aim of this study was to compare thein vitrobinding of bile salts by coconut fiber, a by-product of coconut milk extraction. The raw coconut fiber was processed by different methods before binding test, that is, sieving, pulverizing in mortar, grinding by a dry grinder, digesting with 0.1 N hydrochloric acid (HCl), grinding by a dry grinder and then digesting with 0.1 N HCl. The resultant coconut fiber was sieved to obtain the particle size ranged from 250 to 600 μm. Various bile salts, i.e., sodium deoxycholate, sodium cholate and sodium taurocholate, were individually tested and analyzed by high performance liquid chromatography. The results showed that sodium deoxycholate was bound by sieved coconut fiber (9.64%), mortar-ground coconut fiber (12.91%), grinder-ground coconut fiber (28.31%), acid-digested coconut fiber (41.14%), and grinder-ground and acid-digested coconut fiber (37.54%). Similar results were obtained when sodium cholate and sodium taurocholate were tested but to a lesser extent. It can be concluded from these results that coconut fiber may have potential application as a cholesterol-reducing agent.
Chemometrics-Assisted UV Spectrophotometric Method for Determination of Metformin Hydrochloride and Glyburide in Pharmaceutical Tablets
Authors: Sratthaphut Lawan , Ruttanakorn Kanong
Published: December 2014

This study aims to estimate simultaneously metformin hydrochloride (MET) and glyburide (GLY) in a multicomponent tablets dosage form by spectrophotometric method using chemometric approaches such as principal component regression (PCR) and partial least-squares regression (PLS). Because of highly overlapped in UV spectra and difference proportions of two active ingredients, the conventional univariate calibration methods was not allowed without previous separation. The linearity ranges used to construct the calibration matrix were selected in the ranges from 40.00 to 200.00 mg L-1for MET and from 1.00 to 10.00 mg L-1for GLY. The absorbances were measured in the wavelength range of 200-400 nm, using ethanol as solvent. The resulting UV spectra were subjected to PCR and PLS algorithms and the optimum numbers of principal components (PCs) were selected according to prediction residual error sum of squares (PRESS) values of leave-one out cross-validation. The number of PCs for MET and GLY were found to be 5, 3 by PCR and 5, 3 by PLS, respectively. A set of synthetic mixtures was employed to verify the models and the performance of the models were shown in the values of the root mean square error in prediction (RMSEP). RMSEP values of MET and GLY were 1.806, 0.256 for PCR and 1.802, 0.185 for PLS, respectively. The suitable calibration models were applied to the analysis of these compounds in pharmaceutical formulation.
Effect of Drug Loading and Process Temperature on Physicochemical Properties of Manidipine Hydrochloride Solid Dispersion
Authors: Chamsai Benchawan , Sriamornsak Pornsak
Published: December 2014

Binary solid dispersions of manidipine hydrochloride (MDP) and polyethylene glycol (PEG) 4000 are prepared by melting method. Drug loading and process temperature are varied in the range of 5-30% and 150-210°C, respectively. After melting, only the formulation using 5% MDP and process temperature of 210°C showed yellow clear solution and halo pattern of powder X-ray diffractograms with the absence of peaks. These results indicated that the higher process temperature (210°C) can melt all MDP powders and provide the amorphous product. Moreover, only the higher carrier content can change the crystalline form of MDP to the amorphous form. A clear, solid solution could not be prepared when the drug loading was higher than 5%. In this study, the melting technique avoiding the use of organic solvent was successfully applied to prepared binary solid dispersion.
Determination of Heavy Metals in Herbal Drinks Using ICP-MS
Authors: Limmatvapirat Chutima , Limmatvapirat Sontaya , Charoenteeraboon Juree , Wessapan Chantana , Kumsum Anchalee , Jenwithayaamornwech Siriporn , Luangthuwapranit Pattaravadee
Published: December 2014

Seven groups of herbal drinks including gum karaya, Indian gooseberry, Noni Indian mulberry, cat's whiskers, prickly-leaved elephant's foot, black galingale, and Ling zhi mushroom contain a variety of bioactive compounds such as polysaccharides, terpenes, saponins, and flavonoids. The extracts of these plants have several biological activities such as analgesic, anti-inflammatory, antibacterial, antioxidant and chemoprotective activities that can promote health. The popular uses of herbal drinks in Thailand raise the question about safety of their products, especially for heavy metal contamination. The concentrations of heavy metals such as As, Pb, Cu, Zn, Fe, and Cd in twenty one samples from seven groups of herbal drinks were determined by ICP-MS. None of herbal drinks passed the permissible limits under the Notification of Ministry of Public Health (No. 214) B.E. 2543 (2000) Re: Beverages in Sealed Container by the virtue of the Food Act B.E. 2522 (1979), Thailand. Moreover, the concentrations of Pb and Zn in all analyzed samples were higher than the permissible limits. The concentrations of Fe in almost all analyzed samples as well as the concentrations of As, Cd, and Cu in some analyzed samples were higher than the permissible limits. The levels of heavy metals found in this study raise concerns, not only for the safety of Thai consumers, but also the quality of herbal drinks available in Thailand.
Bioherbicidal Activity of Annona squamosa L. against Lactuca sativa L. and Mimosa pigra
Authors: Phuagphong Patamawan , Nawanopparatsakul Srisombat , Kitcharoen Nudchanart
Published: December 2014

The phytotoxic effects of leaves and seeds from Annona squamosa extracts on lettuce (Lactuca sativa L.) seeds and Mimosa pigra were evaluated. A. squamosa leaf dichloromethane extracts reduced germination and seedling growth of lettuce seeds. In field study, A. squamosa leaf dichloromethane extracts was applied on M. pigra after growing. Fresh weight of M. pigra was decreased with increasing concentrations of leaf dichloromethane extracts. These results suggest that dichloromethane extracts from leaves of A. squamosa may have growth inhibitory substances. Thus, our study indicated that leaf dichloromethane extracts have phytotoxic activity which could be utilized as bioherbicide for future weed control.
In Vitro Comparison of Probiotic Properties of Lactobacillus fermentum SK54 Isolated from New Born Baby with Lactobacillus rhamnosus GG ATCC 53103
Authors: Kaewiad Kanyanat , Kaewnopparat Sanae , Kaewnopparat Nattha
Published: December 2014

A lactobacillus strain isolated from the feces of a healthy baby was identified as Lactobacillus fermentum SK54. The probiotic properties of this strain including antimicrobial activity, survival in acid, bile, simulated gastric fluid [SGF] and simulated intestinal fluid [SIF], antibiotic susceptibility and adherence to Caco-2 cells were examined and compared them with a well known commercial probiotic strain Lactobacillus rhamnosus GG ATCC 53103 isolated from human intestine. L. fermentum SK54 and L. rhamnosus GG showed inhibitory properties toward gastrointestinal pathogens i.e., Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella Typhimurium, and Shigella sonnei by cylinder-plate assay. The inhibitory substances from L. fermentum SK54 composed of acid substances naturally produced by lactobacilli and high molecular weight proteinaceous compound [MW > 3.5 kDa] which sensitive to proteolytic enzymes, pH stability [pH 2.0-5.0] and heat stability [60, 80, 100°C for 10 min and 121°C for15 min]. L. rhamnosus GG produced only acid inhibitory substances. Both strains survived well at low pH [pH 2.0-4.0], bile salts [0.1-0.3% w/v], SGF and SIF. They also had the same 14 tested antibiotic sensitivity pattern and expressed high adherence to Caco-2 cells. This study provides a rationale to support L. fermentum SK54 as a potential probiotic to prevent or act as a therapeutic agent against pathogenic strains.
Exploring DNA Barcode Information of Selected Thai Medicinal Plants
Authors: Rungpragayphan Suang , Pamonsinlapatham Perayot , Powthongchin Busaba , Prommanee Wikanda , Wongakson Piyaporn
Published: December 2014

DNA barcode is referred to specific ranges, sequences or fragments of DNA used for identification organisms at genus or species levels. There are several plant DNA barcodes which are currently studied, such as ITS (Internal Transcribed Spacer), ITS2 (Internal Transcribed Spacer 2), matK, psbA-trnH, rbcL, trnL-trnF. In this work, ITS, ITS2 and psbA-trnH sequences of many medicinal plants in the “Thai Medicinal Plant DNA Barcode Database” were studied. Total of 163 DNA barcodes from 75 plant families were processed and analysed. ATCG contents, %GC or %CG found, ATG patterns, and alignment patterns were investigated. Also, sequences relationships among families were discussed. This information will be useful for authentication and quality control of herbal medicine.
Determination of Heavy Metals in Moringa oleifera Capsules by ICP-MS
Authors: Limmatvapirat Chutima , Limmatvapirat Sontaya , Charoenteeraboon Juree , Phaechamud Thawatchai
Published: December 2014

Moringa oleifera Lam. leaf capsules collected from markets in Nakhon Pathom, Thailand were determined for 11 heavy metals (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) by inductively coupled plasma-mass spectrometry (ICP-MS) using acid digestion for sample preparation. The concentrations of Al, As, Cr, Cu and Hg in all samples of M. oleifera capsules were found within permissible limits and normal ranges. In contrast, Fe, and Zn concentrations in all samples were higher than permissible limits. Furthermore, the concentrations of Cd, Mn, Ni, and Pb in some samples were higher than permissible limits and normal ranges. The presence of elevated levels of Cd, Fe, Mn, Ni, Pb, and Zn in M. oleifera capsules is a serious matter of concern. Therefore, it is important that doctors and consumers are aware of this matter especially during the routine taking of M. oleifera capsules.
Validated UV-VIS Spectrophotometric Method and Stability Assessment of Extemporaneously Prepared Ceftazidime Ophthalmic Solution for Hospital Use
Authors: Panchapornpon Danuch , Chongcherdsak Noppadol , Nuchtavorn Nantana , Burimart Chamaiporn , Simmasut Naphaparin , Karnlaong Suchanya
Published: December 2014

A simple, rapid and cost effective UV-VIS spectrophotometric method was validated and applied for stability assessment of 5% ceftazidime in extemporaneous ophthalmic solution in various conditions. Ceftazidime dissolving in sterile water showed the maximum absorbance (λmax) at 256 nm and no interference was observed. The method validation was determined in term of linearity, intra-day and inter-day precision, accuracy, limit of detection (LOD) and limit of quantitation (LOQ) according to ICH guideline. Spectrophotometric response was linear with r2 = 0.9998 in the range of 5-25 μg/mL. The mean recovery was 99.38% with percent relative standard deviations (%RSDs) of 0.83. Intra-day and inter-day precision showed %RSDs of < 1.00%. LOD and LOQ were 2.60 and 7.88 μg/mL, respectively. The method was reliable for stability study of extemporaneous ceftazidime ophthalmic solution. Results showed that the amount of ceftazidime in extemporaneous formulation stored in both ambient and accelerated conditions dramatically decreased within 1 day. However, the preparation was stable at 2-8 °C for 7 days. In conclusion, the storage temperature had greatly impact on ceftazidime ophthalmic solution therefore it should be kept in the refrigerator for a week and its stability could be monitored using the simple spectrophotometric method.
Cholic Acid-Modified Polyethylenimine for Gene Delivery into Human Carcinoma Cells
Authors: Weecharangsan Wanlop , Paecharoenchai Orapan , Niyomtham Nattisa , Opanasopit Praneet , Yingyongnarongkul Boon-ek , Lee Robert J.
Published: December 2014

Polyethylenimine (PEI) was modified by cholic acid at a molar ratio of 1:1. Cholic acid (CA)-modified PEI (PEI-CA) were evaluated for formation of DNA complexes. PEI-CA/pEGFP plasmid DNA complexes were characterized for their size and zeta potential. Gel electrophoresis showed total retardation for PEI-CA/pEGFP complexes formed at weight ratios above 0.25. The particle size and zeta potential of the complexes at a polymer-to-DNA ratio of 0.5 were 295.3 nm and 30.5 mV, respectively. The transfection efficiency of PEI-CA/pEGFP complexes was comparable to unmodified PEI. Cytotoxicity result showed that PEI-CA had lower cytoxicity than PEI. This study suggests that PEI-CA has potential utility as a gene delivery carrier.
Decylglucoside Microemulsion Systems Containing Coenzyme Q10: Formulation, Physicochemical Characterization and Stability
Authors: Pakpayat Natthida , Boonme Prapaporn
Published: December 2014

This study aimed to develop green microemulsions (MEs) for loading coenzyme Q10 (CoQ10). Decylglucoside, a surfactant in the group of alkyl polyglycosides (APG), was used in the formulations since it is biodegradable and non-ionic, leading to low toxic products and friendly properties to the environment. Two blank MEs, i.e., M1 and M2 were prepared by simple mixing dicaprylyl ether, decylglucoside, sorbotan monolaurate and water in the concentrations of 70%, 2.5%, 22.5% and 5%, respectively for M1 and 60%, 6%, 24% and 10%, respectively for M2. Afterwards, M1 and M2 were incorporated with 5% CoQ10 to obtained QM1 and QM2, respectively. All samples were studied for physicochemical properties and stability under accelerated condition. It was found that they were transparence and absence of liquid crystals. Their rheological profiles indicated low viscosity and Newtonian flow. After stability test by freeze thaw for 5 cycles, physicochemical properties of M1, M2, QM1 and QM2 were not obviously different from those at the initial. In addition, more than 97% of label amount of CoQ10 were found in both QM1 and QM2 after stability study. The results indicated that the investigated decylglucoside MEs were suitable systems for incorporation with CoQ10.
Preparation of Eudragit® L Beads for Intragastric Floating Drug Delivery
Authors: Nernplod Tassanee , Akkaramongkolporn Prasert , Sriamornsak Pornsak
Published: December 2014

The aim of this study was to prepare matrix beads made of enteric polymer, Eudragit® L, metronidazole and various amounts of cetyl alcohol (0, 0.1 and 1%). Eudragit® L, metronidazole and cetyl alcohol were dissolved in acetone and then extruded into dichloromethane. The influence of amount of cetyl alcohol on floating and drug release behavior of matrix beads of Eudragit® L was investigated. The results showed that, after extruding, cetyl alcohol dissolved out from the beads already formed, resulting in a porous structure. Thus, the beads can float in simulated gastric fluid for more than 8 hours. Different amounts of cetyl alcohol had a slight effect on the drug release. However, the increased amount of cetyl alcohol in the formulations significantly sustained the drug release while the beads remained floating. The results suggest that Eudragit® L beads could be used as a carrier for intragastric floating drug delivery.
Lysozyme Release from Lipid-Based Implants
Authors: Portugal Mota Joana , Campos Alexandre , Shuwisitkul Duangratana , Saraiva Nuno , Nicolai Marisa
Published: December 2014

To better understand lipid-based implants applied to proteins, lysozyme was used as a model protein and was loaded into lipid-based implants in different contents. Cylindrical and spherical implants loaded with lysozyme presented a smooth surface. Protein loading efficiency decreased with increasing lysozyme loading. Lysozyme kept its activity after different implant preparation techniques. Drug release tremendously increased by increasing protein loading from 8.9 to 13.7% (w/w), for cylindrical implants. Lysozyme release was faster from cylindrical implants when compared with the spherical ones. Furthermore, by increasing the hydrophobicity of the lipid, protein release decreased. This study demonstrates the potential use of lipid-based implants for the controlled release of proteins.
Analysis of Operation of AVC System in Fuzhou Power Grid
Authors: Xiong Jun Jie , He Wei , He Hao
Published: December 2014

Through the statistics of AVC system equipment availability, closed loop rate, action number and success rate, analyses the operation of AVC system in Fuzhou power grid, there are still many problems, such as closed loop rate is not high, some AVC substation remote low success rate.In order to effectively improve the pertinent measures from the design, operation and maintenance, fixed value management etc..
The Study of Characteristic Impedance of Conductive Transmission Line in FPC(Flexible Printed Circuit Board) Design and Process
Authors: Li Bing , Liu Yi Lun , Zhang Xuan Dong , Pan Zi Jun
Published: December 2014

To meet the demand of the signal stable at high speed, the key is control precision for the characteristic impedance of FPC. This article is intended to study the strip-line structure for reducing cross-talk (noise) and their theoretical analysis and calculation. By varying effect factor and countermeasure in the production process of FPC, and the optimal process parameter have been obtained. By using the some testing technology, the impedance of strip-line in FPC have been tested.
The Design of Semiconductor Laser Driver and Simulation Analysis of Constant Current Drive Circuit Based on Multisim 10
Authors: Wu Li Bo
Published: December 2014

This article focused on the characteristics of the semiconductor laser, designed a practical semiconductor laser driver, which provides two ways of working, including constant current and constant power operating mode. The article focuses on the application of negative feedback theory in semiconductor laser driver design, and done simulation experiments study for constant current drive circuit with simulation software Multisim 10. This driver has soft-start delay protection, preventing electric shock and current limit protection circuits.
A New 3×3 Discrete Soliton Hierarchy with Self-Consistent Sources
Authors: Li Li
Published: December 2014

In this paper, we consider a discrete soliton hierarchy with self-consistent sources by using higher-dimensional matrix spectral problem. Then a new discrete soliton hierarchy with self-consistent sources is obtained.
Power Reduction Techniques in Cloud Data Centers
Authors: Tang Lei , Cai Zheng Ce , Chen Guo Long , Li Xian Wei
Published: December 2014

In recent years, cloud computing has received much attention from both academia and engineering areas. With more and more companies beginning to provide cloud services, more and more data centers are being built. Recent studies show that the energy consumed by cloud data centers accounts for a large fraction of the total power consumption today. This motivates us to survey power reduction techniques in cloud data centers.
Research on the Frame System of Digital Library Mobile Cloud Service Platform
Authors: Yao Min
Published: December 2014

Mobile cloud computing provides a deeper hierarchical tangibility for the construction and environment of digital library and mobile cloud services will certainly become the service mode of the future digital library. From three aspects: information resources integration, the expansion of mobile terminal device capability, information service innovation, this paper discusses upgrade of overall strength of mobile cloud design to digital library information service. At the same time, it also detailed introduces the main function of mobile computing platform layer, mobile cloud library platform layer and mobile terminal application layer.
Phase-Selective Synthesis of a Silicoaluminophosphate Molecular Sieve with 3-Aminopropyltriethoxysilane as the Silica Source
Authors: Bai Ya Dong , Zhang Hai Rong , Bai Pei Wan , Liu Hong Yan , Han Shen Hua , Zhang Wen Shan , Wang Bo , Yuan Kai , Song Dian Hua , Luo Yao Ya
Published: December 2014

Silicoaluminophosphate (SAPO) molecular sieves with CHA and AFI structures have been synthesized under hydrothermal conditions from similar reaction mixtures using 3-Aminopropyl-triethoxysilane as silicon source. The XRD analysis indicated that the phase selectivity could follow the sequence of SAPO-34→SAPO-34+ SAPO-5→SAPO-5 →amorphous phase with increasing the amount of the silicon source. The phase selectivity can be explained by the increasing alkalinity of the medium with the 3-Aminopropyltriethoxysilane concentration.
Preparation Cu-Doped Carbon Aerogels and their Adsorptive Desulfurization Performance
Authors: Zhang Shi Min , Jin Shuang Ling , Jin Ming Lin , Shao Xia , Zhang Rui
Published: December 2014

Cu-doped carbon aerogels were prepared by the sol-gel polymerization of resorcinol with formaldehyde in aqueous solution to produce organic gels that are supercritically dried in n-hexane and subsequently pyrolyzed in an inert atmosphere, using sodium carbonate as catalyst and copper acetate as copper source. The addition amount of the copper acetate in the initial reaction mixture has a profound effect on the surface morphology and pore texture of the resulting aerogel. It is shown that the introduction of copper lead to generation of ultrafine micropores. The desulfurization performance of the as-obtained carbon aerogels was evaluated by selective adsorption of dibenzothiophene (DBT) as a model sulfur compound and benzene as a competitive aromatic compound. It is found that the adsorption capacity for DBT is related to the volume of micropores. And the selectivity is improved with the increase of copper content, indicating the presence of copper is favorable to DBT retention on the surface via its π-complexation effect.