• Volume 36,Issue 5,2015 Table of Contents
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    • >Special Column: National Young Scholar/Local Science Foundation
    • Loose volume model research on the interference fit compressor rotor using the method of temperature difference

      2015, 36(5):445-450. DOI: 10.7535/hbkd.2015yx05001

      Abstract (2361) HTML (0) PDF 990.80 K (3576) Comment (0) Favorites

      Abstract:In order to dismantle non-destructively the impeller and shaft under interference fit, the loaded temperature is planned reasonably for the temperature difference dismantling process. Through selecting suitable loaded temperature parameters, the desired dismantling effect can be acquired. Through theoretical analysis and FEM calculation with ANSYS, the loose volume model of the mating surfaces between the impeller and the shaft during the temperature difference dismantling process is built. Besides, through changing relevant parameters, the influence of the temperature heating location and the heating time on the loose amount between the shaft and hole is analyzed, and the reasonable heating temperature, heating location and heating time are obtained. The results show: when the other factors are constant, the temperature loading on the impeller hub is better than on the flow channel, and when the heating time is 1 400 s, the loose amount between the shaft and hole is the largest.

    • Tension response analysis of mooring system and movement response analysis of drilling rig based on the AQWA

      2015, 36(5):451-458. DOI: 10.7535/hbkd.2015yx05002

      Abstract (2399) HTML (0) PDF 1.13 M (2752) Comment (0) Favorites

      Abstract:The environmental loads such as wind, wave, flow onto drilling rig and mooring system of the HaiYangShiYou 981 are analyzed according to the actual working condition in South China Sea. The Haiyang Shiyou 981 drilling rig is chosen as the research object for mooring positioning system. The 3D model of the platform is established first by using the AQWA software to simulate and analyze the motion response of the drilling device under the action of wave load. As the deep water drilling rig is fixed in the sea with twelve anchors which are symmetrical distribution, the influence of top pretension angle on dynamic response of mooring system and motion response of drilling rig under different environmental load is analyzed by changing the inclination angle of the pretension at the top of the drilling rig.

    • An evaluation method on seat comfort based on optical motion capture

      2015, 36(5):459-466. DOI: 10.7535/hbkd.2015yx05003

      Abstract (2256) HTML (0) PDF 1.55 M (3694) Comment (0) Favorites

      Abstract:To research the sitting posture comfort evaluation method, through the example of comfort evaluation of the ergonomic seat and standard office seat, a methodology is introduced to evaluate the sitting posture comfort combining ergonomics theory. The proposed method is based on optical motion capture system, pressure sensor and JACK software, and TRC file is acquired by using EVART real-time capture software for identifying the spatial motion trail of human body. Then MATLAB software is used to analyze the human body motion data, and the sitting posture angle difference data for human body in different seats is acquired. TRC file is loaded into JACK software, and with the TAT REPORTER of JACK software, muscle force, moment of force and fatigue data, etc. are output, which are compared with the actual measured data from experiments, and ergonomics method is used for the evaluation. The result shows that the method of considering joint angles combining JACK software for data output is effective for evaluating sitting comfort.

    • Posture parameters optimization of a structured light 3D angle measuring system

      2015, 36(5):467-473. DOI: 10.7535/hbkd.2015yx05004

      Abstract (2037) HTML (0) PDF 906.57 K (3331) Comment (0) Favorites

      Abstract:To improve the measurement precision of the structured light target angle, this paper studies the relation between the structured light system parameters and measurement accuracy of the angle. Firstly, the main system structure parameters influencing the angle measurement precision are analyzed based on the structured light measurement principle; secondly, simulation research on the laws of how the structured parameters influence the angle measurement precision are conducted, and the optimized range of values of the structured parameters is proposed; finally, the experimental studies show that, the optimized parameters can improve the angle measurement precision effectively, which lays the design foundation for later improvement schemes of the structured light 3D four-wheel alignment instrument.

    • Research on static strength and weld sizing of transverse fillet welded joints

      2015, 36(5):474-479. DOI: 10.7535/hbkd.2015yx05005

      Abstract (2116) HTML (0) PDF 1.24 M (3288) Comment (0) Favorites

      Abstract:In order to improve the weld sizing precision of modern thin-walled welded structures, disadvantages of conventional shear strength definition for fillet welds are analyzed. With detailed investigation on stress state of transverse fillet weld, a new equation which could depict correctly stress state in weld is proposed. Then, based on load capacity of weld and rule of equal strength respectively, weld sizing equation of transverse fillet weld is derived with known load and unknown load. At last, the relationship between strength of transverse welded joints and weld leg size is investigated according to test results. The results indicate that, strength of welded joints with appropriate weld size and welding procedure can be equal to that of base material, and oversized weld can not only lead excessive welded distortion, but also reduce joints’ strength.

    • Predictive control strategies for energy saving of hybrid electric vehicles based on traffic light information

      2015, 36(5):480-486. DOI: 10.7535/hbkd.2015yx05006

      Abstract (1943) HTML (0) PDF 885.16 K (3289) Comment (0) Favorites

      Abstract:As the conventional control method for hybrid electric vehicle doesn’t consider the effect of known traffic light information on the vehicle energy management, this paper proposes a model predictive control intelligent optimization strategies based on traffic light information for hybrid electric vehicles. By building the simplified model of the hybrid electric vehicle and adopting the continuation/generalized minimum residual method, the model prediction problem is solved. The simulation is conducted by using MATLAB/Simulink platform. The simulation results show the effectiveness of the proposed model of the traffic light information, and that the proposed model predictive control method can improve fuel economy and the real-time control performance significantly. The research conclusions show that the proposed control strategy can achieve optimal control of the vehicle trajectory, significantly improving fuel economy of the vehicle, and meet the system requirements for the real-time optimal control.

    • >Chemistry and Chemical Industry
    • Preparation and visible-light photocatalytic performances ofcyclized polyacrylonitrile/TiO2 nanocomposites

      2015, 36(5):487-492. DOI: 10.7535/hbkd.2015yx05007

      Abstract (2145) HTML (0) PDF 1.09 M (2852) Comment (0) Favorites

      Abstract:TiO2 nanomaterials were prepared by a conventional sol-gel method with tetrabutyl titanate as Ti source. The polyacrylonitrile solution with dimethyl sulfoxide as solvent was added into TiO2 sols to form TiO2 gels containing polyacrylonitrile, then the as-prepared TiO2 gels were heat-treated to prepare cyclized polyacrylonitrile/TiO2 (CPAN/TiO2) nanocomposites. The CPAN/TiO2 nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis diffuse reflection spectroscopy (DRS) and photoluminescence spectroscopy (PL). The visible-light photocatalytic performances of CPAN/TiO2 nanocomposites were investigated by evaluating the decomposition of methyl orange. The results reveal CPAN/TiO2 nanocomposites exhibit excellent visible-light photocatalytic acitivity and stability, and show the highest visible-light photocatalytic activity when the mass ratio of CPAN to TiO2, heat-treatment temperature and time are 1∶300, 270 ℃ and 1 h, respectively.

    • Synthesis and characterization of carboxymethyl tamarind

      2015, 36(5):493-498. DOI: 10.7535/hbkd.2015yx05008

      Abstract (2470) HTML (0) PDF 870.03 K (2897) Comment (0) Favorites

      Abstract:Series of carboxymethyl tamarind kernel polysaccharide (CMTKP) with different degree of substitution (DS) were prepared by the reactions of tamarind kernel polysaccharide (TKP) and sodium monochloroacetic acid (SMCA) in alkaline aqueous isopropanol. The influence of mole ratio of NaOH to SMCA, SMCA concentration, reaction temperature and time on DS, reaction efficiency (RE) as well as the transmittance and apparent viscosity of CMTKP aqueous solution was investigated. The maximum DS of 0.92 and the RE of 77% were obtained. The solubility of CMTKP in cold water and the freeze-thaw stability were apparently improved and the transmittance of the mass fraction of 2% CMTKP aqueous solution could be up to 97%. Thermal stability decreased showed by TGA, and crystalline region reduced with the increasing of DS after carboxymethylation showed by XRD. The structure was characterized by FT-IR and solid-state 13C NMR.

    • Study on the influence factors for chlorogenic acid content in Shuanghuanglian oral liquid

      2015, 36(5):499-503. DOI: 10.7535/hbkd.2015yx05009

      Abstract (2006) HTML (0) PDF 723.69 K (2514) Comment (0) Favorites

      Abstract:This paper aims to find the reason of the decrease of chlorogenic acid in Shuanghuanglian oral liquid, and to enhance the stability of chlorogenic acid by improving the preparation process. The extraction method of Lonicerae japonicae flos, concomitance ingredients and excipients such as buffer, antioxidant, solubilizer and complexing agent which may affect the stability of chlorogenic acid were studied by HPLC method. Result shows that the mixed extraction, single extraction and extraction temperature have no significant effect on the extraction yeild; the main influence factor of chlorogenic acid content is the pH value of Shuanghuanglian oral liquid,and the stability of chlorogenic acid can be enhanced by adjusting the pH value of oral liquid; five factors including baicalin, buffer, antioxidant, solubilizer and complexing agent which may affect the content of chlorogenic acid are studied. It is concluded that buffer has obvious effect on the content of chlorogenic acid, while the other four factors have no significant effect.

    • Preparation of carboxymethyl chitosan grafted polyacrylic acid hydrogel and its evaluation in vitro and in vivo

      2015, 36(5):504-510. DOI: 10.7535/hbkd.2015yx05010

      Abstract (2057) HTML (0) PDF 1.04 M (2760) Comment (0) Favorites

      Abstract:A novel pH-sensitive carboxymethyl chitosan graft polyacrylic acid(CMC-g-PAA) hydrogel is fabricated via a free radical heat-initiated graft copolymerization reaction with acrylic acid(AA) and carboxymethyl chitosan(CMC) as monomers. The polymerization is successful, which is confirmed via fourier transform infrared spectroscopy (FT-IR). The result of swelling experiment indicates that the final CMC-g-PAA hydrogel has significant pH-sensitivity. Insulin(INS), as a model drug, is loaded into the hydrogel and 216.5 mg/g incorporation of INS is obtained. In vitro release profiles suggest that INS release is (16.3±2.6)% when pH is 1.2 after 2 h. INS release is (57.2±3.5)% in PBS with pH of 7.4 after the next 2 h. The study indicates that the CMC-g-PAA hydrogel loaded with INS could targeted deliver INS in intestinal, and avoid that INS is destroyed by gastric acid and pepsin. The experiment result on animals indicates that the CMC-g-PAA hydrogel loaded with INS has hypoglycemic effects. With different concentrations of CMC-g-PAA hydrogel co-cultured with Caco-2 cells, the cell survival rates are close to 100%, which indicates that the hydrogel has no cytotoxicity. In sum, the novel CMC-g-PAA hydrogel has a prospective application in the specific-site delivery of proteins and peptides.

    • >Mechanical, Electronics and Information Science
    • A self-adaptive step Cuckoo search algorithm based on dimension by dimension improvement

      2015, 36(5):511-516. DOI: 10.7535/hbkd.2015yx05011

      Abstract (1972) HTML (0) PDF 775.00 K (2944) Comment (0) Favorites

      Abstract:The choice of step length plays an important role in convergence speed and precision of Cuckoo search algorithm. In the paper, a self-adaptive step Cuckoo search algorithm based on dimensional improvement is provided. First, since the step in the original self-adaptive step Cuckoo search algorithm is not updated when the current position of the nest is in the optimal position, simple modification of the step is made for the update. Second, evaluation strategy based on dimension by dimension update is introduced to the modified self-adaptive step Cuckoo search algorithm. The experimental results show that the algorithm can balance the contradiction between the global convergence ability and the precision of optimization. Moreover, the proposed algorithm has better convergence speed.

    • Design of tension control system for fiber placement equipments

      2015, 36(5):517-522. DOI: 10.7535/hbkd.2015yx05012

      Abstract (2107) HTML (0) PDF 878.43 K (2603) Comment (0) Favorites

      Abstract:Aiming at the tension control requirements of automatic fiber placement equipments and the problems of traditional tension control system, the hammer tension control system is designed. The hammer is used as a buffer unit in the system, and the tension can be indirectly controlled by the position of the hammer. The system adopts the motion controller as the core element of the system, the AC servo motor as the actuator and the laser position sensor as the detector. The fuzzy PID control algorithm is used for the position control of hammer, which can avoid tension fluctuation by full consideration of the acceleration of the hammer. Prototype experimental results show that this system can avoid the problems of disconnection and relaxation of fiber, meanwhile, the static difference ratio and fluctuation ratio can meet the requirements of engineering practice.

    • Aircraft group control based on consensus

      2015, 36(5):523-531. DOI: 10.7535/hbkd.2015yx05013

      Abstract (1920) HTML (0) PDF 943.01 K (2375) Comment (0) Favorites

      Abstract:This paper presents a new algorithm for the consistency of information based on the average state, and it is applied in first-order system and second-order system. Frequency domain analysis method is used to obtain sufficient conditions for the convergence rate. Due to the inevitable presence of the communication network itself and the other individual time lag problems between individuals, the paper further analyzes the stability of the system under time delay which uses the proposed consistency algorithm. For second-order multi-agent system, firstly, consensus algorithm of average state under the undirected network is proposed and based on the given conditions, sufficient conditions are obtained under which the system achieves static consistent and dynamic consistent. Finally, the algorithm is applied in a multi-aircraft formation control groups.

    • Similar words analysis based on POS-CBOW language model

      2015, 36(5):532-538. DOI: 10.7535/hbkd.2015yx05014

      Abstract (4827) HTML (0) PDF 1.19 M (4488) Comment (0) Favorites

      Abstract:Similar words analysis is one of the important aspects in the field of natural language processing, and it has important research and application values in text classification, machine translation and information recommendation. Focusing on the features of Sina Weibo's short text, this paper presents a language model named as POS-CBOW, which is a kind of continuous bag-of-words language model with the filtering layer and part-of-speech tagging layer. The proposed approach can adjust the word vectors' similarity according to the cosine similarity and the word vectors' part-of-speech metrics. It can also filter those similar words set on the base of the statistical analysis model. The experimental result shows that the similar words analysis algorithm based on the proposed POS-CBOW language model is better than that based on the traditional CBOW language model.

    • >Biological Science
    • Natural biomaterials for construction of cartilage scallfold

      2015, 36(5):539-545. DOI: 10.7535/hbkd.2015yx05015

      Abstract (2209) HTML (0) PDF 1.15 M (2559) Comment (0) Favorites

      Abstract:Once damaged, articular cartilage should be repaired or replaced owing to its limited self-repair capacity. But traditional methods for treating cartilage defect are not satisfying. In contrast, tissue engineering offers promising hope for cartilage disease. In the three main factors of tissue engineering, such as seed cells, scallfold materials and signal molecules, scallfold materials play a fundamental role. The paper reviews cartilage scallfold materials, introduces collagen type Ⅱ, hyaluronic acid and chondroitin sulfate which naturally exist in cartilage, and dicusses the current problems and the future directions of tissue engineering scallfold.

    • Preparation of cross-linked enzyme aggregates with crude-pored microspherical silica core

      2015, 36(5):546-552. DOI: 10.7535/hbkd.2015yx05016

      Abstract (1534) HTML (0) PDF 1.21 M (2286) Comment (0) Favorites

      Abstract:In this study, phenylalanine ammonia lyase (PAL) is used as model, and the cross-linked enzyme aggregates of PAL with crude-pored microspherical silica core (NH-PAL-CLEAs) are prepared. The conditions for the preparation of NH-PAL-CLEAs are optimized. Moreover, some characteristics of the NH-PAL-CLEAs are examined. The optimized conditions for preparing NH-PAL-CLEAs are as follows: 117.75 mg silica, 0.2% (v/v) glutaraldehyde and 1 mL free PAL solution (2 U). Under optimized conditions, the maximum activity recovery of NH-PAL-CLEAs reaches 25%. Compared with PAL-CLEAs, the resulting NH-PAL-CLEAs can be easily separated from the reaction mixture by natural precipitation without centrifugation and filtration treatments. Moreover, NH-PAL-CLEAs show superior operational stability. This technique not only overcomes the difficulty to recover CLEAs due to their small particle sizes and soft for many industrial applications, but also reduces production cycle and energy consumption. As a result, this technique shows superior application prospect for enzyme immobilization.

Editor in chief:朱立光

Inauguration:

International standard number:ISSN 1008-1542

Unified domestic issue:CN 13-1225/TS

Domestic postal code:

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