Статті в журналах: "+621.311"

1

Sivitska, Svitlana. "IDENTIFICATION OF STRATEGIC PRIORITIES OF INVESTMENT INTO DEVELOPMENT OF ALTERNATIVE ENERGETICS." ЕКОНОМІКА І РЕГІОН Науковий вісник, no. 3(64) (June 7, 2017): 52–59. http://dx.doi.org/10.26906/eir.2017.3(64).876.

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UDC 338:336.02:621.311 Svitlana Sivitska, Ph.D., Associate Professor at Finance and Banking Department, Vice-Rector for Scientific, Educational, Social Work and International Cooperation. Poltava National Technical Yuri Kondratyuk University. Identification of strategic priorities of investment into development of alternative energetics. There are the stages of the methodology for choosing the strategic priorities of investing in alternative energy explored in the article. The potential of alternative energy analyzed. The strategic priorities of alternative energy have been explored. An integrated analysis of the potential of alternative energy is carried out on the territorial basis done. The matrix of choice of strategic priorities of investing in alternative energy determined. Keywords: energetic security, alternative energetics, renewable sources of energy, investment, strategic priorities, matrix.

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2

Zhao, Tian Yang, Dan Jiang, Song Yu, Jie Wang, and Ping Yang. "Analysis of High Pressure Transients in Water Hydraulic Pipeline Using Matlab/Simulink." Key Engineering Materials 621 (August 2014): 311–16. http://dx.doi.org/10.4028/www.scientific.net/kem.621.311.

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Based on the continuity equation and the motion equation of fluid dynamics, a mathematical model of high pressure transients in water hydraulic pipeline is presented. In the model, the friction item is consist of steady friction item and dynamic friction item, using the Darcy-Weisbach equation to solve steady viscous friction item and using four exponential terms instead of weighting function to solve dynamic friction item. By finite difference method accompanied with Matlab/Simulink, an example of high pressure turbulent flow in water hydraulic pipeline is configured so as to simulate the dynamic characteristics of pressure transients. The comparison between the observed result and the simulation result shows the mathematical model of high pressure transients in water hydraulic pipeline with turbulent flow is reasonable.

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3

Kryshchuk, R. S. "RESEARCH OF ELECTROMAGNETIC FIELD FOR U-SHAPED INDUCTOR IN THE MAGNETIC-PULSE PROCESSING OF NONMAGNETIC METALS." Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini 2020, no. 55 (March 19, 2020): 90–93. http://dx.doi.org/10.15407/publishing2020.55.090.

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4

Dou, Yong Jie, Jian Sheng Xu, Cong Liang Deng, Xiao Li Zhao, Leng Nie, Yang Yu, Ming Wang, and Tao Song. "Design of Automatic Nucleic Acid Extraction Instrument Based on Magnetic Nanobeads." Advanced Materials Research 621 (December 2012): 313–16. http://dx.doi.org/10.4028/www.scientific.net/amr.621.313.

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In this paper, an automatic nucleic acid extraction instrument is described. It consists of mechanical components, motor controlling module, temperature controlling module and computer. Also, a prototype has been designed and constructed. The maximum sample throughput of this prototype is 96, the sample volume is 300-1000ul, the maximum sample handling time is about 60min, the sample temperature controlling range is from room temperature to 95oC, and the accuracy of temperature controlling achieved is about ± 2oC.

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5

Zhang, Hai Quan, Xin Wang, Hong Ke Li, Jun Feng Nie, and Ji Guo Liu. "Design and Engineering Verification of HTR-PM Fuel Handling." Advanced Materials Research 621 (December 2012): 317–25. http://dx.doi.org/10.4028/www.scientific.net/amr.621.317.

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Abstract. HTR-PM is a twin-reactor structure pebble bed modular reactor. With the gather-scatter fuel handling system (FHS), handling and circulating function of twin reactors’ fuel elements are performed under a non-shutdown continuous condition. Relying on separate pipeline system of sphere fuel main circulation, FHS achieved automatic operation in the structural model by sphere fuel’s gravity flowing and pneumatic conveying in the twin reactors. The FHS adopted the international experience at design and operation of similar systems, especially based on that of HTR-10. However, some key components and technologies were improved so that fuel handling of HTR-PM becomes more reliable. All of the improved components and technologies will be tested in a full-scale hot testing facility, and some of them were verified and validated with the help of separated cold testing facilities. The functions and design of HTR-PM FHS is introduced in this paper. Design and engineering test of the FHS in HTR-PM demonstration power plant are reviewed.

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6

Ren, Xiao Li, Xue Mei Shang, Chen Fan, and Yan Ting Du. "A Design of Electric Hydraulic Lifting Device Supported by Mechanical Structure." Key Engineering Materials 621 (August 2014): 317–22. http://dx.doi.org/10.4028/www.scientific.net/kem.621.317.

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In hydraulic transmission, Hydraulic pressure can not support heavy objects long time. For the shortcoming, an electro-hydraulic lifting device is designed with mechanical structural supporting; Electric motor is the motive power. The weight is lifted by hydraulic transmission technology; the base of the device is set up a lifting rigid leg and pushing forward Casters .After hydraulic system lifting heavy objects, the lifting devices rely on the support tube, mechanical positioning tube and rigid supporting legs to lock the lifting position. In order to ensure the same high of support on different positions, a vertical fine adjustment mechanism is set. The design solves the problem that hydraulic transmission cannot lift long time. The lifting device is safe operation, easy moved, accuracy positioning, and stable support, energy-saving and environmental protection.

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7

Liu, Wen Xuan, Hui Feng Wang, Guang Lin Wang, and Dong Xiang Shao. "Research of Non-Contact Stiffness Measurement Technology." Key Engineering Materials 621 (August 2014): 331–36. http://dx.doi.org/10.4028/www.scientific.net/kem.621.331.

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This article describes the elastic element of the servo valve, elaborates the definition of the stiffness of elastic element, analyzes the characteristics of existing rigidity measurement system, points out the limitations of the existing rigidity measurement system when it measures the large-stiffiness elastic element, utilizes a new measuring principle based on the existing stiffness test systems, uses the more accurate laser displacement measurement method to overcome the weaknesses of the existing stiffness test system, improves the measurement accuracy, makes stiffness measurements more accurate and promotes the stiffness measurement technology of the servo valve elastic element.

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8

Li, Yong Xin, Feng He Wu, Fei Xia Cheng, Jun Wang, and Wei Yuan Wang. "Venation-Like Layout Design of Plate's Stiffeners." Key Engineering Materials 621 (August 2014): 351–56. http://dx.doi.org/10.4028/www.scientific.net/kem.621.351.

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Traditional orthogonal pattern is ordinarily employed in stiffener configurations of plates in engineering. Layout optimization design of the stiffeners can realize the win-win situation of structure lightweight and bearing property. The existing methods generally transform the challenge into strengthening regional distribution, and the resulting vague regions need identification by post-processing technology. Structure similarity exists between dicotyledonous venation pattern and irregular stiffener distribution. The paper extracted some mechanical factors from the topology regularity and morphogenesis theory of dicotyledonous venation, and static bionic mechanical model was constructed for bionic rib pattern. A new venation growth method with hierarchical veins was proposed based on it. Then typical plate example was designed for proper stiffener distribution, and compared through static experiment.

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9

Zhang, Pei Pei, Ke Ying Zhu, Li Qiang Su, and Ru Xiao. "Preparation and Properties of Graphene/Polyamide 6 Composites by Melt Compounding." Advanced Materials Research 621 (December 2012): 31–34. http://dx.doi.org/10.4028/www.scientific.net/amr.621.31.

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In this paper, graphene was obtained by Oxidation-reduction method. The obtained graphene was characterized by XRD and FTIR. On this basis, graphene/polyamide 6(PA6) composites were prepared by melt compounding. The well-dispersed graphene nanosheets in PA6 matrix was investigated by SEM. The properties were characterized by XRD, DSC and TGA. The results showed that the α-phase of polyamide 6 induced into γ-phase by adding graphene. The crystallization temperature and the crystallinity of composites have been increased in some degree. Besides, the composite has a higher thermal stability.

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10

Lypkivskyi, K. O., and A. G. Mozharovskyi. "INCREASING THE EFFICIENCY OF USING AN AUTOTRANSFORMER WITH A CORE OF MAGNETIC CIRCUIT AS A PART OF THE TRANSFORMER-AND-SWITCHES EXECUTIVE STRUCTURE OF AN AC VOLTAGE STABILIZER." Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini 2020, no. 55 (March 19, 2020): 46–51. http://dx.doi.org/10.15407/publishing2020.55.046.

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11

Xu, Zhi Hua, Dao Fang Zhang, Ling Ling Wu, and Su Hui Li. "Research on a Novel Environment-Friendly Synthetic Material Based on Sludge." Advanced Materials Research 621 (December 2012): 303–6. http://dx.doi.org/10.4028/www.scientific.net/amr.621.303.

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This study prepared a low energy consumption and environment-friendly synthetic material without modification, which was capable of removing ammonium nitrogen (NH4+-N) and phosphorus (TP) in the water effectively and at the same time maintaining high mechanical strength. The best mixture ratio of synthetic material was investigated. The results showed that with a mass ratio of 1:2:0.05 for cement, zeolite and microwave-treated sludge, the water-cement ratio of 0.4 and a volume ratio of 1:60 for foaming agent to water, the 7-days compressive strength of this material reached 5.8 MPa, which met the strength requirement of related demonstration projects. Meanwhile, synthetic material manifested effective adsorption capacities and showed a maximal adsorption amount of 0.23 mg/g for NH4+-N and 0.32 mg/g for TP. The pseudo-second-order kinetics model was found to fit the NH4+-N and TP adsorption processes well.

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12

Tao, Wu. "Digital Walking Control System Study for Asphalt Paver Based on DSP." Advanced Materials Research 621 (December 2012): 309–12. http://dx.doi.org/10.4028/www.scientific.net/amr.621.309.

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The digital control system of the walking system of the asphalt paver based on the TMS320LF2407 DSP is introduced in this paper. The paper accomplishes the software and hardware design of the control system, integrates the PID and fuzzy control into the design of the digital control system so as to conduct constant-velocity control under paving. The thesis proves fuzzy-adjustable-PID control is superior to traditional PID control by simulation and analysis. The feasibility and rationality of control system design are proved by the test.

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13

Sun, Dan, Yan Ting Ai, Wan Fu Zhang, and Jian Gang Yang. "Design of a New Kind of the Radial Annular Seal for the Aeroengine." Advanced Materials Research 621 (December 2012): 326–29. http://dx.doi.org/10.4028/www.scientific.net/amr.621.326.

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To minimize fluid leakage loss and improve rotordynamic stability of traditional aeroengine seals, a new kind of radial annular rim seal (RARS) is presented in this paper. Comparing with the conventional labyrinth rim seal (LRS), the fluid leakage direction is modified from the axial to radial direction. The flow resistance increases, and the flow-induced force is greatly reduced. The completed three-dimensional CFD model between RARS and LRS were employed to analyze the inherent characteristics of the fluid flow in the whole passage. Calculated results show that RARS has less leakage and fluid-induced force compared to the LRS.

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14

Liu, Chang Hong. "Collaborative Design of the Injection Mould." Advanced Materials Research 621 (December 2012): 330–33. http://dx.doi.org/10.4028/www.scientific.net/amr.621.330.

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In this paper, a method for injection mould of concurrent development was put forward based on graph theory and design structure matrix. In activities identification phase, coupled activity was identified by Boolean operation of adjacent matrix, accessible matrix and strong connected matrix. After re-engineering and optimizing, a structured model is established to open out the principle of the concurrent injection mould design process. The method has the advantage of flexibility to deal with the interrelationship of various tasks, which greatly improved the efficiency of development.

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15

Yang, Ping, and Ping Sheng Liang. "An Improved MPPT Algorithm for Off-Grid Wind Power Generator Based on Hill Climbing Method." Advanced Materials Research 621 (December 2012): 334–39. http://dx.doi.org/10.4028/www.scientific.net/amr.621.334.

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The control algorithm of maximum power point tracking (MPPT) plays a key role in improving the wind energy conversion efficiency. This paper proposes an improved MPPT control algorithm based on hill climbing method, which combines proportional control with hill climbing method, with the advantage of precise steady-state control from hill climbing method, the combination with proportional control enhances the speed of dynamic response. By using this algorithm in the wind power simulation system based on Matlab, we get the simulation results for both fixed and variable wind speed. The result shows that this improved algorithm can track the maximum power point of wind power generation system quickly and precisely.

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16

Xie, Fei, Bu Xiang Zhou, Qin Zhang, and Long Jiang. "Line Loss Rate Forecasting Based on Grey Model and Combination of Neural Network." Advanced Materials Research 621 (December 2012): 340–43. http://dx.doi.org/10.4028/www.scientific.net/amr.621.340.

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This thesis is mainly focusing on the research of the method for line loss rate forecast by adopting grey model combined with neural network. Firstly, GM(1,1) model can be used to analyze and calculate line loss rate change trend. The input variables of the neural network could be determined by grey relationship of related factors. Three-Layer BP model for line loss rate forecast is constructed, and then the eventual result can be obtained by using the combined model of GM(1,1) and neural network method. An example is taken to prove the precision improved for line loss rate forecast by the proposed method studied in the thesis.

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17

Ge, Mao Gen, Ming Zhou Liu, Ming Xin Zhang, Jing Hu, Wen Rui Wu, and Llin Ling. "The Classification Research about the Uncertain Factors of Job Shop Manufacturing Shop Re-Scheduling." Advanced Materials Research 621 (December 2012): 344–47. http://dx.doi.org/10.4028/www.scientific.net/amr.621.344.

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In order to have an effective induction and treatment about the various uncertain factors in the process of Job Shop manufacturing shop re- scheduling under the uncertain environment, Through the description of all kinds of uncertainties and disturbances during the workshop production process, here put forward a way to divide these uncertain factors into different types, such as type A uncertain factors which can cause scheduling scheme invalid, type B uncertain factors which have an uncertain impact on scheduling scheme and type C uncertain factors which may lead the schedule partial failure.

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18

Zhang, Bing, Li Li Xing, Dan Qi Chen, Li Xie, Yue Li, and Qun Bo Ouyang. "An Embedded Positioning System Applied to the Seismic Exploration." Advanced Materials Research 621 (December 2012): 348–51. http://dx.doi.org/10.4028/www.scientific.net/amr.621.348.

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An embedded positioning system, which can be applied to seismic exploration, is designed. Meeting the characteristics of field work and the instantaneity of data transmission, the system is composed by the positioning terminals and supplemented by earthquake decision-making experts and monitoring center. With the style of mobile phone message and monitoring center, the real-time transmission and query of positioning data are mobile.

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19

Tan, Zhong Fu, Shu Xiang Wang, Chen Zhang, Li Qiong Lin, and Yin Hui Zhao. "A Simulation Model for Multi-Factor Sensitivity Analysis on Energy Demand." Advanced Materials Research 621 (December 2012): 352–55. http://dx.doi.org/10.4028/www.scientific.net/amr.621.352.

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This paper analyses multi influencing factors of energy demand, using energy demand forecast regression model reveals inner relations between each factor and energy demand. Establish simulation model of the relation between GDP, energy intense and energy demand. Under the change in population, urbanization and energy efficiency, this paper gives analysis model of energy demand change.

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20

Zhao, Huan, Jiang Long Yu, Arash Tahmasebi, and Pei Hong Wang. "An Improved Particle Swarm Optimization Algorithm with Invasive Weed." Advanced Materials Research 621 (December 2012): 356–59. http://dx.doi.org/10.4028/www.scientific.net/amr.621.356.

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This paper presents a hybrid algorithm based on invasive weed optimization (IWO) and particle swarm optimization (PSO), named IW-PSO. IWO is a relatively novel numerical stochastic optimization algorithm. By incorporating the reproduction and spatial dispersal of IWO into the traditional PSO, exploration and exploitation of the PSO can be enhanced and well balanced to achieve better performance. In a set of 15 test function problem, the parameters of IW-PSO were analyzed and selected, and the computational results show that IW-PSO can effectively obtain higher quality solutions so as to avoid being trapped in local optimum, comparing with PSO and IWO.

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21

Zhao, Huan, Jiang Long Yu, Arash Tahmasebi, and Pei Hong Wang. "Monitoring of Efficiency and NOx Emissions at a Coal-Fired Utility Boiler." Advanced Materials Research 621 (December 2012): 360–63. http://dx.doi.org/10.4028/www.scientific.net/amr.621.360.

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In order to improve boiler efficiency and to reduce the NOx emission of a coal-fired utility boiler using combustion optimization, a hybrid model was proposed to monitor boiler efficiency and NOx emissions. In this model, operational parameters were inputs, and its features were selected by kernel principal component analysis (KPCA). The relationships between the selected features and combustion products such as NOx emissions, unburned carbon and oxygen content in flue gas were mapped by -support vector regression ( -SVR), and then boiler efficiency was calculated by analytical model. The parameters of hybrid model were determined by grid search and 5-fold cross validation. The predicted results indicate that the presented hybrid model can monitor both efficiency and NOx emissions of coal-fired utility boiler, and the predicted performance of KPCA- -SVR model is more superior, comparing the other two models.

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22

Chen, Yu Pu, Yuan Hua Qiao, and Jun Miao. "Color Image Segmentation Based on Dynamic Model and Power Spectrum." Advanced Materials Research 621 (December 2012): 364–69. http://dx.doi.org/10.4028/www.scientific.net/amr.621.364.

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In this paper, the locally coupled neural oscillator model and power spectrum are introduced to solve the color image segmentation problem. Firstly the single neuron oscillator model is developed, the model parameter is set so as to create limit circle simulating the activity of neuron. Then the locally coupled network model is developed, taking R, G, Bas external input separately, the network output three dynamic orbits representing R, G, B for each image point. Lastly, the power spectrum of the orbits is calculated for each image point, the color image is segmented using the calculated power spectrum. The performance is comparable to the results from other segmentation methods.

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23

Teng, Jia Ying, Xian Guo Wu, Ge Qian Zhou, Wei Jia Zhao, and Jing Cao. "Study on Integrated Project Delivery Construction Project Collaborative Application Based on Building Information Model." Advanced Materials Research 621 (December 2012): 370–74. http://dx.doi.org/10.4028/www.scientific.net/amr.621.370.

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In the last few years, in order to solve the problems of traditional delivery mode in construction industry, such as over budget, project delay and so on, Integrated Project Delivery (IPD) as an effective solution has become a hot spot in China and abroad. IPD with special implementation of process has many advantages compared with the traditional delivery mode. In this paper, the modeling strategy of BIM in IPD project is proposed, and the application of BIM in all stages of IPD on basis of engineering project is analyzed. The study provides foundation for the further collaboration application of IPD with BIM.

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24

Guo, Jun Li, Jia Ying Teng, Shu Qin Li, Dong Yan Wan, and Xue Jiang. "Study on Electronic Kanban Management System in Steel Structure Engineering of an International Expo Centre." Advanced Materials Research 621 (December 2012): 375–80. http://dx.doi.org/10.4028/www.scientific.net/amr.621.375.

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E-Kanban management is an effective tool to achieve lean and just-in-time(JIT) production. Based on the analysis of the traditional Kanban and the advantages of E-Kanban, types and function of E-Kanban in construction industry are proposed. The framework of E-Kanban management in steel structure engineering of an international expo center which covers decision layer, business layer and technical support layer is built in this paper. The E-Kanban management system and the models of E-Kanban in steel structure engineering are designed on basis of this framework. The system focuses on function and application of Transmit E-Kanban, produce E-Kanban, temporary E-Kanban and feedback E-Kanban. The research of this paper provides the theory and practice foundation for the application of E-Kanban in construction industry.

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25

Zhang, Ya Xin, Hai Li Pan, and Xiao Zi Xu. "Analysis of Vibration Cause and Damping Design to Lubricating Oil Pipe of 10-K-302C Compressor Based on Numerical Simulation ." Key Engineering Materials 621 (August 2014): 304–10. http://dx.doi.org/10.4028/www.scientific.net/kem.621.304.

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Vibration of pipe is the most frequently fault appeared in chemical engineering industry. In this paper, in order to resolve the problem of vibration in exceed of the set standard for the lubricating oil pipe of 10-K-302C compressor of DuShanzi petro-chemical company, the three-dimensional model of the pipe were established by using ANSYS Workbench, and the natural frequency and mode vibration of the pipe were obtained. Through ANSYS bidirectional coupled fluid-structure analyzing method, the variety of the pressure and velocity of the lubricating oil in the pipe, vibration frequency and the displacement of the pipe under working condition were carried out. By contrasting the analysis result between the numerical simulation and measured actually, the validity and accuracy of the numerical simulation have been affirmed and it has been found that the resonance and the large fluid pressure fluctuation were two main reasons caused the pipe vibration. Based on the conclusions above, two ways to reduce the vibration have put forward and the best way have determined.

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26

Tang, Wei Dong, Qing Kun Zhou, Da Peng Fan, Fei Tuan Xiong, and Nian Zhong Xia. "Design of a Large-Torque Precise Cable Drive Mechanism." Key Engineering Materials 621 (August 2014): 323–30. http://dx.doi.org/10.4028/www.scientific.net/kem.621.323.

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Precise cable drive has been developed as a new-style transmission element that has the advantages of low backlash, high stiffness, high efficiency, no friction and no lubrication, and is widely used in electro-optical tracking system. A precise cable drive mechanism is designed in this paper. Its torque output is greater than 50Nm and precision is less than 0.1mrad. Size of the cable is selected base on the maximum load of the cable evaluated in the process of the reciprocating motion. In order to improve the driving capacity, design the cable-groove match strategy with the non-intervene cable wrapping method. A figure eight pattern wrapped method and screw pitch of the cable wrapped line is designed. The influence of the contact angle on the preload force and the influence of the preload force on the backlash are simulated by the software Matlab when the mechanism driving the maximum load. At last magnitude of the contact angle and the preload force is confirmed.

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27

Chen, En Ping, Shao Hui Li, Feng He Wu, and Chong Min Jiang. "Structure Design of Biaxial Rotary Milling Head with High-Torque, High-Precision and Mechanical Spindle." Key Engineering Materials 621 (August 2014): 337–45. http://dx.doi.org/10.4028/www.scientific.net/kem.621.337.

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As a key component of heavy five-axis linkage CNC machine tools, the existing mechanical biaxial rotary milling heads are usually driven by worm gear, timing belt, or multi-stage gears. Worm gear is inefficiency to transmit motion, hard to maintain the accuracy and difficult to eliminate all clearance; Timing belt can be seriously worn and cannot maintain good accuracy; and multi-stage gears transmission has defects such as long chain, low transmission stiffness. This paper aims at designing a biaxial rotary milling head with large output torque of 3000Nm, high precision and high rigidity. So a new design for biaxial rotary milling head with mechanical spindle, gear transmission and swinging fork structure is proposed. An integral supporting axis is applied to increase the rigidity of A-axis; through the closed numerical loop control based on precise encoder and the decoupling technology of feed motion of A/C axis, the contradiction between large reduction ratio and high precision transmission is solved, and then the requirement of high positioning accuracy (10") is met. Theoretical calculation and simulated analysis shown, the new design not only can guarantee transmission accuracy and dynamic characteristics of biaxial rotary milling head, but also can improve its structural stiffness and meet the high demands of large torque, high precision and high rigidity.

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28

Xie, Xin, Shi Xun Fan, Da Peng Fan, and Hua Liu. "A Piezo/Gear Compound Drive: Principles Analysis and Simulation." Key Engineering Materials 621 (August 2014): 346–50. http://dx.doi.org/10.4028/www.scientific.net/kem.621.346.

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Increasing demands regarding the light-weight, high-torque and high-precision actuator are inducing the need for new actuators and new drive principles. This paper introduces a novel principle for transforming the linear motion of high performance piezoelectric actuators into continuous rotation is implemented by two piezoelectric actuators acting on a driving gear covering a driven gear with a slightly smaller diameter. By driving the piezoelectric actuators, the driving gear is energized to move on a circular trajectory around the driven gear which is thereby slowly rotated. Firstly, the structure and driving mechanism is introduced. Secondly, transmission ratio, the demand driving force and displacement are analyzed theoretically and by the means of simulation analysis. Finally, the bottlenecks of mechanism design and machining are presented. Some instructive reference for the structure design of Piezo/Gear compound drive is provided.

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29

Wang, Yong Mei, and Xi Gui Wang. "Oil Temperature Control System PID Controller Algorithm Analysis Research on Sliding Gear Reducer." Key Engineering Materials 621 (August 2014): 357–64. http://dx.doi.org/10.4028/www.scientific.net/kem.621.357.

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With the development of computer technology, communication technology, electronic technology and automatic control technology, computer control technology widespread application, has been widely used in iron and steel, petroleum, chemical, electric power, building materials, machinery manufacturing, automotive, textile, transportation and other industries. Controlled by computer, we can realize the control of high reliability, process visualization, remote monitoring, data storage and processing. The simulation of PID control algorithm, and focuses on the study and analysis of the digital PID control algorithm, the marine gear lube oil temperature control system model, the three parameters of digital PID: proportional coefficient, integral constant, differential constant on the control system performance was also analyzed.

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30

Wang, Yong Mei, and Xi Gui Wang. "Marine Gear Reducer Design Device of Lubricating Oil Temperature Control System." Key Engineering Materials 621 (August 2014): 365–71. http://dx.doi.org/10.4028/www.scientific.net/kem.621.365.

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Signal of PLC controller by PID operation after the output of numerical simulation between 0~1, and solid state relay can receive only signal, digital or switched on or off. Only connected the two, temperature control system can be realized. The experimental approach is to learn from PWM pulse width modulation technology, the numerical analog PID controller output into the heating time in a cycle, namely, solid state relay on time. By this method, the indirect control heating rod of equivalent power, the power output of the heating rod according to the control signal of controller output, so as to realize marine gear oil temperature PID regulation. This paper designs the control system used in the experiment. The temperature control experiment system; design of the electrical schematic diagram of the temperature control system, including two parts electrical schematic diagram of control circuit and main circuit of temperature control system design process. At the same time, the experimental scheme is designed. Analysis of the mechanism of temperature balance control object, and focus on the temperature within the experimental results are analyzed.

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31

Wang, Zhan Li, Yan Juan Hu, Yan Wei Chen, and Hua Chao Guo. "Design and Co-Simulation Analysis of Flip Climbing Transmission System for Stair-Climbing Wheelchair." Key Engineering Materials 621 (August 2014): 372–77. http://dx.doi.org/10.4028/www.scientific.net/kem.621.372.

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: In this paper, I designed a differential planetary gear for flip climbing transmission system which was applied to the star-climbing wheelchair. According to space limitation and the stair climbing per formance requirements, distributing the number of teeth for each gear under transmission ratio requirements. Furthermore, modifying tooth profile parameters on each gear for improving the quality of the transmission. Using SolidWorks software established t he three-dimensional model. Then impact and contact simulated analysis is studied based on the SolidWorks Motion Plugins to get transmission and meshing condition. At the same time, gave the SolidWorks Motion output data as a result of the input data to t h e SolidWorks Simulation. Through the simulation results validate the output center gear tooth can meet the carrying capacity requirements. On the other hand, it also provides theoretical basis for further improve the structure design.

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Guo, Rong Xing, Jie Wang, and Peng Ge Ma. "Research on the Automatic Test System of Bus Dashboard Function Based on Machine Vision." Key Engineering Materials 621 (August 2014): 378–84. http://dx.doi.org/10.4028/www.scientific.net/kem.621.378.

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This paper studies the automatic test system of bus dashboard EOL (end of line) based on machine vision. Based on machine vision theory, Identification and detection algorithm of panel signal indicator elements and tachometer pointer readings was studied combining single-frame still images and real-time processing of color video image, the automatic parallel detection of multiple dashboard was realized by distributed network architecture. This paper first describes the function requirements, the overall composition and working principle of automatic test system. Then, it proposes an automatic identification and detection algorithm of dashboard symbol sheets and pointer position. Finally, it shows the designing of automatic test software with a self-learning and auto-detection function, and describes the working process of the software. The tests prove that the system is capable of realizing fast and accurate auto-test of bus dashboard functions based on the non-contact of machine vision, which improves the overall efficiency of the bus dashboard line.

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Zheng, Jian Xin, Jie Han, and Chuan Shao Liu. "Numerical Design of Stepped Compound Horn with Longitudinal-Torsional Vibration under Single Acoustic Excitation." Key Engineering Materials 621 (August 2014): 385–91. http://dx.doi.org/10.4028/www.scientific.net/kem.621.385.

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The mechanism of longitudinal-torsional vibration (LTV) realized by using converter with multiple diagonal slits (MDS) was analyzed based on the acoustic wave propagation when acoustic wave enters obliquely from steel to air. The influences of geometrical parameters of the stepped compound horn with multiple diagonal slits on natural frequencies of LTV were studied with finite element analysis (FEA). The design procedure of stepped compound horn with LTV was provided. The vibration characteristics of actual horn were analyzed with simulation and test. The FEA results show that LTV of the output end of the stepped compound horn may be realized when the input end is excited by longitudinal vibration at certain natural frequency if suitable geometrical dimensions are selected, and the amplitude of the horn is periodical; the trajectory of the particle in the output end is helical curve. The test results indicate that LTV may be realized by stepped compound horn under single acoustic excitation, and the vibration frequency is close to the simulation result, and its vibration properties are good. This method may be applied to design the acoustics system of ultrasonic machining with LTV under single acoustic excitation.

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Cheng, Xin Xin, Xu Dong Pan, and Guang Lin Wang. "Design of the Output Performance Test System of Permanent Magnet Linear Force Motor." Key Engineering Materials 621 (August 2014): 392–99. http://dx.doi.org/10.4028/www.scientific.net/kem.621.392.

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Electrical energy directly converted into mechanical energy of linear motion by linear force motor, greatly enhancedthe rapid response ability and control precision of the feed system. The product quality of linear force motor can be effectively improved by design a performance test system of linear force motor. The paper designed a performance test system of linear force motor based on the Labview virtual instrument platform, and test project of linear force motor has been planned, the test method, the structure of the test device, power drive module, step motor load part, data acquisition and the software system all have been completed. The test system realized automatic and manual two different kinds of test methods, data acquisition and management and processing function and the good human-machine interface, the linear force motor dynamic and static parameter, including input current, output force and output displacement and the relationships between them have been tested.

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Fan, Ji Wei, Dan Liu, Xiao Li Zhang, Hui Jun Zhao, Zheng Guo Zhang, and Yamin Zheng. "The Effects of B₂O₃ Addition and Sintering Temperature on the Electrical Properties of SnO₂ Based Varistors." Advanced Materials Research 621 (December 2012): 35–38. http://dx.doi.org/10.4028/www.scientific.net/amr.621.35.

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SnO2 based varistor ceramics, as new type of varistor materials, have attracted increasing interest around the world. However, the effect of B2O3 addition on novel SnO2 based varistors is still unclear. In this paper the effects of B2O3 addition on the electrical properties and sintering temperature of the SnO2-Co2O3-Ta2O5 system were investigated. The experiments revealed that addition of trivalent boron can improve the densification of SnO2 based ceramics. The samples doped with 0.025mol% B2O3 had the highest sintering density. However between 0mol% to 0.1mol% B2O3 addition region there was little effect on non-linearity and breakdown field of SnO2-Co2O3-Ta2O5 system. Obviously, the sintering temperature had a predominant influence on the SnO2-Co2O3-Ta2O5 system; the samples sintered at 1400°C were superior to those sintered at 1350°C.

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Huang, Hong Jun, Wang Kang, Guo Shun Wan, and Jiang Lei. "A Research of the Spongy Foams from Interpenetrating Polymer Network of Polyurethane/ Epoxy Resin." Advanced Materials Research 621 (December 2012): 39–43. http://dx.doi.org/10.4028/www.scientific.net/amr.621.39.

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A series of interpenetrating polymer networks (IPN) spongy foams based on polyurethane (PU) and epoxy resin (EP) were prepared by a simultaneous polymerization technique. The PU/EP IPN spongy foams with different epoxy content were investigated. The results showed that initial adhesion increased with the increment of EP content, and gained the highest value when the content reached to 20%; FTIR suggested the formation of PU/EP IPN; the density also increased with the increasing content of epoxy; the highest degree of uniformity in bubbles were observed in foams with 20% content of epoxy resin.

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Yu, Nan, Ying Chun Liang, Jia Xuan Chen, and Yong Bo Guo. "Simulation Study of Material Deformation in Monocrystal Silicon Nano-Machining." Key Engineering Materials 621 (August 2014): 32–37. http://dx.doi.org/10.4028/www.scientific.net/kem.621.32.

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Molecular dynamics simulations method is used on the study of material deformation in monocrystal silicon during nanomachining. Both nanoindentation and nanocutting by a diamond tool tip is investigated using LAMMPS. Characterization methods such as coordination number and labeling atoms in different layers have been adopted to study the law of transformation. As the surface atoms are tracked, their transformation law is analyzed and the formation mechanism of the cuttings and finished surface is announced. The impact crystal orientation of silicon on the machining is also studied.

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Li, Yu, and Ping Yan Bian. "A Strategy for On-Line Monitoring the Crosslinking Degree of 3D Printing Hydrogel Fiber Based on Dual-Threshold Enhancement Method." Key Engineering Materials 621 (August 2014): 38–43. http://dx.doi.org/10.4028/www.scientific.net/kem.621.38.

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The optical detection of the crosslinking degree is very important to the forming quality’s on-line control of the hydrogel fibers and tissue engineering scaffolds in 3D printing process at room temperature. For the feature of small scale object, low contrast ratio and unclear outline of the crosslinked area, we processed the crosslinking image with the dual-threshold enhancement method. Firstly, the color image is decomposed into three two–dimensional RGB signals. Secondly, the RGB signals are processed through wavelet transform respectively, and those wavelet coefficients are amplified or reduced with dual-threshold method for the purpose of enhancement and denoising. Then, the new RGB signals are reconstructed by those wavelet coefficients. At last, the new RGB signals are regrouped to get enhanced crosslinking image. Experimental results show that, after processed with this method, the image has a strong sense of color gradation, the details of image are outstanding, and the distinction of the crosslinked zone of the hydrogel fiber is obvious. Moreover, measurement precision of crosslinking degree is improved by 4.58%. This is helpful to improve the performance of the real-time control of crosslinking process.

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Vejmelková, Eva, Dana Koňáková, Monika Čáchová, Martin Keppert, Adam Hubáček, and Robert Černý. "Application of Zeolite as a Partial Replacement of Cement in Concrete Production." Applied Mechanics and Materials 621 (August 2014): 30–34. http://dx.doi.org/10.4028/www.scientific.net/amm.621.30.

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Natural zeolite rocks are known to be able to act as Supplementary Cementitious Materials (SCM) in Portland cement based concrete. Generally SCMs are reacting with portlandite and providing binding hydration products just as Portland cement does. In this way an SCM can substitute certain amount of Portland cement in concrete and thus reduce the related energy consumption and CO2 generation. Due to a large variability of SCMs composition and properties there is not any general rule for an optimum Portland cement substitution level. In this paper, the influence of natural zeolite rock on selected mechanical, hygric and thermal properties of concrete is studied. Experimental results show that the analyzed zeolite is acting as a pozzolan but for higher amounts its application leads to an increase in concrete porosity which affects its properties in a significant way.

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Embong, Rahimah, and Andri Kusbiantoro. "Study on the Early Hydration of Cement Paste Containing Sodium Chloride." Applied Mechanics and Materials 621 (August 2014): 35–38. http://dx.doi.org/10.4028/www.scientific.net/amm.621.35.

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This paper studies the effect of sodium chloride as the additive component in cement paste. Sodium chloride was included at 0.5%, 1%, 1.5%, and 2% by weight of cement content. Analysis on the performance of this reagent was conducted via setting time, compressive strength, and porosity test. Based on the setting time analysis, the inclusion of sodium chloride can extend the initial setting time of cement paste up to 24.91% longer than control specimen. Obstruction on the formation of calcium silicate hydrate gel by sodium and chloride ion was one of the possible causes to this phenomenon. Acceleration on the compressive strength development by sodium chloride was also detected. It appears that sodium chloride was able to de-flocculate the coagulated cement particles and reduced the viscosities of cement slurries; hence resulted in faster early hydration process.

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Thu, Nguyen Thi Ai, and Nguyen Mong Giao. "The Influence of Gamma Radiation on Magnetic Properties of Fe₃O₄, Co_0.8Ni_0.2Fe₂O₄, Co_0.8Zn_0.2Fe₂O₄ Ferrite Magnetic Materials." Applied Mechanics and Materials 621 (August 2014): 39–43. http://dx.doi.org/10.4028/www.scientific.net/amm.621.39.

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The influence of radiation on magnetic material has been investigated in many researches which had proved that the magnetic properties of hard magnetic were unchangeable under radiation effect[1],[2],[3],[4],[5],[6].In this work, we performed the study of the influence of gamma radiation on Fe3O4, Co0.8Ni0.2Fe2O4, Co0.8Zn0.2Fe2O4. The60Co gamma radiation was emitted on ferrite magnetic materials with doses 1000, 1500, 2000 kGy. Analyzing magnetic properties of the materials before and after emitting by Walker Automatic Hysteresisgraphs AMH 20-50. The change of (B-H) loop is insignificant. Our work agrees well with the result of[1][2][3][4].

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Xiong, Yu, Ji Zheng, Song Lin Li, Xue Jia Liu, and Lu Liang. "Investigation on Nano-Sized ZnO Powder Doped with Al³⁺ Prepared by Sol-Gel Method." Advanced Materials Research 621 (December 2012): 3–7. http://dx.doi.org/10.4028/www.scientific.net/amr.621.3.

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Al3+-doped ZnO nano-powder was prepared by sol-gel process, using tin tetrachloride and titanium tetrachloride as starting materials. The crystallinity and purity of the powder were analyzed by X-ray diffraction spectrometer (XRD). And the size and distribution of Al3+-doped ZnO grains were studied using transmission electron microscope (TEM) and scanning electron microscope (SEM). The results showed that the Al3+ was successfully doped into the crystal lattice of tin oxide and that the electric conductivity of Al3+-doped ZnO sample was improved significantly.

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He, Ai Dong, Bang Yan Ye, and Zi Yuan Wang. "Experimental Effect of Cryogenic MQL Cutting 304 Stainless Steel." Key Engineering Materials 621 (August 2014): 3–8. http://dx.doi.org/10.4028/www.scientific.net/kem.621.3.

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Cryogenic MQL is a kind of green machining technology of the combination of cryogenic air and minimal quantity lubrication (MQL). The aim of this research is to determine if the cryogenic MQL technique in turning with Cutting tool with internal cooling structure gives some advantages in terms of tool life, surface roughness and cutting chip breaking. This paper reports the results obtained from turning tests, at one feed rates (0.12mm/r) and one depth of cut (0.4mm) and different cutting speeds (43m/min, 108m/min, 217m/min), and the results obtained show that using cryogenic MQL had some advantages in terms of tool wear, surface roughness and cutting chip breaking compared to using dry cutting and cryogenic air cutting. And the results obtained show that when cryogenic MQL and cryogenic air cutting were applied to high speed cutting, they had more advantages.

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Wu, Jin Wu, and Hai Peng Yuan. "Effect of Orientation Angle on Acoustic Radiation Mode Amplitudes of Laminated Composite Plates." Applied Mechanics and Materials 621 (August 2014): 3–6. http://dx.doi.org/10.4028/www.scientific.net/amm.621.3.

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In this paper, the acoustic radiation mode’s amplitudes of laminated composite plates are studied. The layer wise finite element model is imposed to determine velocity distributions of laminated composite plates. Based on the acoustic radiation mode, the effects of the panel orientation angle on the first three orders acoustic radiation mode’s amplitude of the laminated composite plates are then discussed. A twelve-layer laminated plate was used as an example, and the numerical simulations results show that the effects of the panel orientation angle on the acoustic radiation amplitude of the laminated composite plates are significant.

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Fernandes, Shanlley Cristina da Silva, Rafaella Souza dos Santos, Erica Albanez Giovanetti, Corinne Taniguchi, Cilene Saghabi de Medeiros Silva, Raquel Afonso Caserta Eid, Karina Tavares Timenetsky, and Denise Carnieli-Cazati. "Impact of respiratory therapy in vital capacity and functionality of patients undergoing abdominal surgery." Einstein (São Paulo) 14, no. 2 (June 2016): 202–7. http://dx.doi.org/10.1590/s1679-45082016ao3398.

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ABSTRACT Objective To evaluate the vital capacity after two chest therapy techniques in patients undergoing abdominal surgical. Methods A prospective randomized study carried out with patients admitted to the Intensive Care Unit after abdominal surgery. We checked vital capacity, muscular strength using the Medical Research Council scale, and functionality with the Functional Independence Measure the first time the patient was breathing spontaneously (D1), and also upon discharge from the Intensive Care Unit (Ddis). Between D1 and Ddis, respiratory therapy was carried out according to the randomized group. Results We included 38 patients, 20 randomized to Positive Intermittent Pressure Group and 18 to Volumetric Incentive Spirometer Group. There was no significant gain related to vital capacity of D1 and Ddis of Positive Intermittent Pressure Group (mean 1,410mL±547.2 versus 1,809mL±692.3; p=0.979), as in the Volumetric Incentive Spirometer Group (1,408.3mL±419.1 versus 1,838.8mL±621.3; p=0.889). We observed a significant improvement in vital capacity in D1 (p<0.001) and Ddis (p<0.001) and in the Functional Independence Measure (p<0.001) after respiratory therapy. The vital capacity improvement was not associated with gain of muscle strength. Conclusion Chest therapy, with positive pressure and volumetric incentive spirometer, was effective in improving vital capacity of patients submitted to abdominal surgery.

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Chuah, Yoen Young, Ping-I. Hsu, Wei-Lun Tsai, Hsien-Chung Yu, Feng-Woei Tsay, Wen-Chi Chen, Kung Hung Lin, Yeong Yeh Lee, and Huay-Min Wang. "Short-term vasoactive agent treatment driven by physicians’ preference in acute esophageal variceal bleeding in a tertiary center." PeerJ 7 (November 6, 2019): e7913. http://dx.doi.org/10.7717/peerj.7913.

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Background Vasoactive drugs are frequently used in combination with endoscopic variceal ligation (EVL) in treatment of acute esophageal variceal bleeding (EVB). The aim of study was to assess physicians’ preference of vasoactive agents in acute EVB, their reasons of preference and efficacy and safety of these short course regimens. Methods Cirrhotic patients with suspected EVB were screened (n = 352). Eligible patients were assigned based on the physician’s preference to either somatostatin (group S) or terlipressin (group T) followed by EVL. In group S, intravenous bolus (250 µg) of somatostatin followed by 250 µg/hour was continued for three days. In group T, 2 mg bolus injection of terlipressin was followed by 1 mg infusion every 6 h for three days. Results A total of 150 patients were enrolled; 41 in group S and 109 in group T. Reasons for physician preference was convenience in administration (77.1%) for group T and good safety profile (73.2%) for group S. Very early rebleeding within 49–120 h occurred in one patient in groups S and T (p = 0.469). Four patients in group S and 14 patients in group T have variceal rebleeding episodes within 6–42 d (p = 0.781). Overall treatment-related adverse effects were compatible in groups S and T (p = 0.878), but the total cost of terlipressin and somatostatin differed i.e., USD 621.32 and USD 496.43 respectively. Conclusions Terlipressin is the preferred vasoactive agent by physicians in our institution for acute EVB. Convenience in administration and safety profile are main considerations of physicians. Safety and hemostatic effects did not differ significantly between short-course somatostatin or terlipressin, although terlipressin is more expensive.

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Barros, Hellen Siglia Demetrio, Eniel David Cruz, Adriano Gonçalves Pereira, and Edvaldo Aparecido Amaral da Silva. "FRUIT AND SEED MORFOMETRY, SEED GERMINATION AND SEEDLING VIGOR of Parkia gigantocarpa." FLORESTA 50, no. 1 (December 20, 2019): 877. http://dx.doi.org/10.5380/rf.v50i1.56855.

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The objectives of this work were to characterize fruits and seeds and evaluate seed germination and seedling vigor from fifteen parent plants of Parkia gigantocarpa Ducke. The fresh weight, length, width, and thickness of fruits and seeds were determined. The germination was tested in a sand substrate, with four replications of 25 seeds per treatment (parent plants). The number of days for emergence, emergence percentage, emergence speed index, germination percentage, and seedling dry weight were evaluated. The fruits presented means for fresh weight, length, width, and thickness of 115.0 g; 621.3 mm; 60.8 mm, and 9.8 mm, respectively. The seeds presented means for fresh weight, length, width, and thickness of 1.1 g, 22.8 mm, 11.2 mm, and 7.0 mm, respectively. The emergence was fast and uniform, which occurred from the fifth to the sixth day after seeding, reaching 91% germination for the parent HB9, but not differing from the parents HB2, HB3, and HB6. The seedlings from the parents HB2, HB3, HB6, and HB9 were more vigorous due to their higher dry matter accumulation. The results found showed that, even belonging to the same species, P. gigantocarpa seeds from different parent plants present variability in biometric characteristics of fruits and seeds. The seed collected from different parent plants showed differences in germination capacity and seedling vigor.

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Klapötke, Thomas M., Hendrik Radies, and Jörg Stierstorfer. "Alkali Salts of 1-Methyl-5-nitriminotetrazole – Structures and Properties." Zeitschrift für Naturforschung B 62, no. 11 (November 1, 2007): 1343–52. http://dx.doi.org/10.1515/znb-2007-1101.

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Alkali salts of 1-methyl-5-nitriminotetrazole (1, 1-MeAtHNO2) are common intermediates in the synthesis of alkylated nitriminotetrazoles and their derivatives and can be used as brilliant coloring agents in modern pyrotechnics, due to their cations in combination with the high nitrogen contents. The structures of the crystalline state of A+ 1-MeAtNO2− · xH2O (A = Li+, x = 1 (2), A = Na+ (3), A = K+ (4), A = Rb+ (5) and A = Cs+ (6), all x = 0) were determined using low temperature single crystal X-ray diffraction. In addition, the compounds were characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (1H, 7Li, 13C, 14N, 15N), elemental analysis and differential scanning calorimetry (DSC). Since tetrazoles are known to be promising energetic materials, the heats of formation were calculated using experimentally determined heats of combustion obtained by bomb calorimetry. The sensitivities of all compounds were tested using the BAM drophammer and friction tester showing them to have no sensitivity neither against friction (<360 N) nor impact (<50 J). Crystal data: 2: monoclinic, P21, a = 3.5152(3), b = 12.3308(9), c = 7.3381(5) Å , β = 92.068(7)°, V = 317.86(4) Å3, Z = 2, δ = 1.756 g cm−3; 3: monoclinic, P21/n, a = 3.6071(2), b = 8.3254(5), c = 18.955(1) Å, β = 91.365(6)°, V = 569.07(6) Å3, Z = 4, δ = 1.939 g cm−3; 4: monoclinic, P21/c, a = 3.6310(1), b = 8.6487(2), c = 19.8598(5) Å, β = 94.945(2)°, V = 621.34(3) Å3, Z = 4, δ = 1.948 g cm−3; 5: monoclinic, P21/n, a = 8.7948(2), b = 10.1640(2), c = 15.0571(3) Å , β = 92.470(2)°, V = 1344.71(5) Å3, Z = 8, δ = 2.258 g cm−3; 6: monoclinic, P21/n, a = 6.3539(1), b = 13.4762(3), c = 8.2876(2) Å, β = 99.245(2)°, V = 700.42(3) °Å3, Z = 4, δ = 2.618 g cm−3.

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Wang, Huijun, Bing Zhang, and Shufa Du. "Trends of body mass index among children and adolescents in China, 1997‐2011 (621.3)." FASEB Journal 28, S1 (April 2014). http://dx.doi.org/10.1096/fasebj.28.1_supplement.621.3.

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Schäffer, Michael W., Somdutta Sinha Roy, Shyamali Mukherjee, and Salil K. Das. "Improved High‐Performance Liquid Chromatography Method with Diode Array Detection for Simultaneous Analysis of Retinoic Acid Isomers, Retinol, Retinyl esters, Vitamin E, and Selected Carotenoids in Guinea Pig Tissues." FASEB Journal 22, S1 (March 2008). http://dx.doi.org/10.1096/fasebj.22.1_supplement.621.3.

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