中南大学学报·社会科学版杂志

发表咨询:400-808-1731

订阅咨询:400-808-1751

中南大学学报·社会科学版杂志 CSSCI南大期刊 北大期刊

Journal of Central South University(Social Science)

  • 43-1393/C 国内刊号
  • 1672-3104 国际刊号
  • 2.16 影响因子
  • 1-3个月下单 审稿周期
中南大学学报·社会科学版是中南大学主办的一本学术期刊,主要刊载该领域内的原创性研究论文、综述和评论等。杂志于1999年创刊,目前已被维普收录(中)、CSSCI 南大期刊(含扩展版)等知名数据库收录,是中华人民共和国教育部主管的国家重点学术期刊之一。中南大学学报·社会科学版在学术界享有很高的声誉和影响力,该期刊发表的文章具有较高的学术水平和实践价值,为读者提供更多的实践案例和行业信息,得到了广大读者的广泛关注和引用。
栏目设置:经济理论经与管理、文史哲、法学、政治学、外国语言研究

中南大学学报·社会科学版 2017年第06期杂志 文档列表

A global-local finite element analysis of hybrid composite-to-metal bolted connections used in aerospace engineering1225-1232

摘要:Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-dimensional(3D) stress variations is prohibitively expensive for a large-scale structure where hundreds of bolts can be present. In this work, the hybrid composite-to-metal bolted connections used in the upper stage of European Ariane 5ME rocket are analyzed using the global-local finite element(FE) approach which involves an approximate analysis of the whole structure followed by a detailed analysis of a significantly smaller region of interest. We calculate the Tsai-Wu failure index and the margin of safety using the stresses obtained from ABAQUS. We find that the composite part of a hybrid bolted connection is prone to failure compared to the metal part. We determine the bolt preload based on the clamp-up load calculated using a maximum preload to make the composite part safe. We conclude that the unsuitable bolt preload may cause the failure of the composite part due to the high stress concentration in the vicinity of the bolt. The global-local analysis provides an efficient computational tool for enhancing 3D stress analysis in the highly loaded region.

Strain induced changes in performance of strained-Si/strained-Si1-yGey/relaxed-Si1-xGex MOSFETs and circuits for digital applications1233-1244

摘要:Growing a silicon(Si) layer on top of stacked Si-germanium(Ge) compressive layer can introduce a tensile strain on the former, resulting in superior device characteristics. Such a structure can be used for high performance complementary metal-oxide-semiconductor(CMOS) circuits. Down scaling metal-oxide-semiconductor field-effect transistors(MOSFETs) into the deep submicron/nanometer regime forces the source(S) and drain(D) series resistance to become comparable with the channel resistance and thus it cannot be neglected. Owing to the persisting technological importance of strained Si devices, in this work, we propose a multi-iterative technique for evaluating the performance of strained-Si/strained-Si1-yGey/relaxed-Si1-xGex MOSFETs and its related circuits in the presence of S/D series resistance, leading to the development of a simulator that can faithfully plot the performance of the device and related digital circuits. The impact of strain on device/circuit performance is also investigated with emphasis on metal gate and high-k dielectric materials.

Effect of process parameters on microstructural and mechanical properties of Ti-SS 304L explosive cladding1245-1251

摘要:The present work pertains to the study of microstructure and mechanical properties of explosively cladded commercially pure titanium(cpTi) with austenitic stainless steel(SS 304L) subjected to varied process parameters, viz., loading ratios(mass of explosive or mass of flyer plate) and preset angles. The microstructural study reveals the transformation from straight to wavy interface while increasing loading ratios. Vickers hardness increases with loading ratios, and the maximum hardness is witnessed in the closer proximity of collision interface. Ram tensile and shear strength of explosive claddings are higher than that of parent plates. While the base plate fails in impact test, the flyer plate is deformed, indicating good impact strength. Increased mass of claddings, due to oxide formation, is witnessed in corrosion tests, which confirms the superiority of explosive claddings in corrosive environment. Triaxial weldability window, an analytical estimation for Ti-SS 304L explosive claddings, is developed and correlated.

Particle size distribution of coal and gangue after impact-crush separation1252-1262

摘要:Based on the separation and backfilling system of coal and gangue, the mineral material impact experiments were conducted utilizing the hardness difference between coal and gangue according to the uniaxial compression experiments. The broken coal and gangue particles were collected and screened by different size meshes. The particle size distributions of coal and gangue under different impact velocities were researched according to the Rosin-Rammler distribution. The relationships between separation indicators and impact velocities were discussed. It is found from experiments that there is a fully broken boundary of coal material. The experimental results indicate that the Rosin-Rammler distribution could accurately describe the particle size distribution of broken coal and gangue under different impact velocities, and there is a minimum overlap region when the impact velocity is 12.10 m/s which leads to the minimum mixed degree of coal and gangue, and consequently the benefit of coal and gangue separation.

An elasto-visco-plastic constitutive model of polypropylene incorporating craze damage behavior and its validation1263-1268

摘要:An elasto-visco-plastic constitutive model incorporating the craze damage behavior was developed for the polypropylene(PP), by using the plastic failure model applied for the concrete, to capture the craze yielding and stress-whitening phenomena. In addition, the developed constitutive model was implemented into finite element codes in Abaqus to simulate the tensile deformation. The standard uniaxial tensile tests were carried out. The stress-strain curves from the uniaxial tensile tests show that the stress keeps decreasing after yielding and the yield stress rises with the increasing of the strain rate. It is worth noting that the craze damage is more visible with higher strain rate. The stress-whitening can be seen clearly around the fracture. The uniaxial tensile tests using specially designed specimen with circular holes weakening were performed for the validation of the developed model. The simulation results of the tensile deformation of the hole-weakened specimen suggest that the stress-whitening could be attributed to the equivalent visco-plastic strain. By comparing between the simulation analysis and the experimental results, the proposed model can describe the stress whitening phenomenon with good accuracy.

Solution behavior of ZnS and ZnO in eutectic Na2CO3-NaCl molten salt used for Sb smelting1269-1274

摘要:The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na2CO3-NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 oC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 oC. In addition, ZnS reacted with Na2CO3 above 900 oC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na2CO3-NaCl molten medium, and that the optimal smelting temperature is below 900 oC.

WO3 nanofibers on ACF by electrospun for photo-degradation of phenol solution1275-1280

摘要:Electrospun WO3 nanofibers were fabricated by coaxial electrospinning and directly annealing WCl6/polyvinylpyrrolidone(PVP) nanofibers on activated carbon fibres(ACF), and characterized by scanning electron microscopy(SEM) and X-ray diffractometry(XRD). The most suitable condition for electrospinning is the mass ratio of WCl6 to PVP 0.6, appropriate amount DMF and ethanol, a voltage of 28 kV, the reception distance of 15 cm, the humidity range within 10% and 20% and the moving rate of the pump 0.001 mm/s. The photocatalytic activities of WO3 nanofibers were evaluated by the photo-degradation of phenol solution under the irradiation of 500 W xenon lamp. The results showed that, the sizes of the fibers are about 100 nm, and after being photodegraded for 210 min, the concentration of phenol decreased from 20.05 mg/L to 8.60 mg/L. Thus, the photo-degradation rate of WO3 nanofibers for phenol solution is 2.87 mg/(L·h).

Simultaneous production of hydrogen and volatile fatty acids from anaerobic digestion of Macrocystis pyrifera biomass residues1281-1287

摘要:The Macrocystis pyrifera biomass residues(MPBRs) after extraction of algin could be applied in anaerobic fermentation. The effects of different pretreatment conditions, substrate concentrations and initial pH values on hydrogen and volatile fatty acid(VFA) production during the anaerobic fermentation of MPBRs were evaluated. The optimal pretreatment conditions, substrate concentration, initial pH values were determined as thermo-alkaline pretreatment at 100 °C with 0.1 mol/L NaOH, 40 g/L and 7.0, respectively. Under these conditions, the maximum hydrogen production was 11.38 mL/g(volatile solids, VS), which was approximately 23 times higher than that of untreated MPBRs. Furthermore, the maximum total volatile fatty acid(TVFA) yield was found to be 0.055 g/g(VS) and the VFA mainly consisted of acetic and butyric acids. The results indicate that the yield of TVFA is positively correlated with hydrogen production, and the MPBRs could produce hydrogen and TVFA simultaneously. In addition, thermo-alkaline pretreatment is proven to be the best method for hydrogen and VFA production.

Dynamics modeling and simulation of a saucer-shaped stratospheric aerostat with an under-slung nacelle1288-1298

摘要:A new concept stratospheric aerostat is investigated which consists of a saucer-shaped hull, multi-vectored thrusters, and an under-slung nacelle. The design of this aerostat involves tradeoffs between conventional airship and high altitude balloon. The sling connection simplifies structure design significantly, but brings challenges for dynamics analysis. Dynamics modeling for this aerostat is a kind of double-body problem with geometric constraint. Nonlinear dynamics model is established by considering the effects of under-slung nacelle. Oscillation behavior of this double-body system is superposed by a long-period oscillation of the hull and a short-period oscillation of the nacelle. The length of sling only influences the short-period oscillation but the mass ratio of nacelle to main body determines the stability of system. Finally, an envelope about mass ratio and maximal open loop forward thrust as well as speed is presented, where the system is stable.

Outlier detection based on multi-dimensional clustering and local density1299-1306

摘要:Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outlier. In this work, an effective outlier detection method based on multi-dimensional clustering and local density(ODBMCLD) is proposed. ODBMCLD firstly identifies the center objects by the local density peak of data objects, and clusters the whole dataset based on the center objects. Then, outlier objects belonging to different clusters will be marked as candidates of abnormal data. Finally, the top N points among these abnormal candidates are chosen as final anomaly objects with high outlier factors. The feasibility and effectiveness of the method are verified by experiments.

Design and implementation of robot serial integrated rotary joint with safety compliance1307-1321

摘要:In order to guarantee safety and stability during physical human-robot-interaction(p HRI) in the occasion of service or industrial operation, a serial integrated rotary joint with the characteristics of passive and active compliance is proposed. Passive compliance is achieved by a designed elastic element, such that the compliant joint may minimize large force which occurs during accidental impacts and, further, may offer more accurate and stable force control and a capacity for energy storage. Meanwhile, the modeling of the compliant joint is comprehensively analyzed, including the effect of the motor model on the overall control system. In order to realize the active compliance, a new method of impedance control is proposed. On the basis of PD control, a more compliant impedance controller is introduced. Experimental results show that the serial integrated rotary joint can provide more effective safety compliance during physical interaction, which has also been well applied in our designed massage robot and rehabilitation robot.

Performance analysis and design of MIMO-OFDM system using concatenated forward error correction codes1322-1343

摘要:This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shift keying(BPSK), quadrature phase shift keying(QPSK), quadrature amplitude modulation(QAM)-16 and QAM-64 with four error correction codes(convolutional code(CC), Reed-Solomon code(RSC)+CC, low density parity check(LDPC)+CC, Turbo+CC) is studied under three channel models(additive white Guassian noise(AWGN), Rayleigh, Rician) and three different antenna configurations(2×2, 2×4, 4×4). The bit error rate(BER) and the peak signal to noise ratio(PSNR) are taken as the measures of performance. The binary data and the color image data are transmitted and the graphs are plotted for various modulations with different channels and error correction codes. Analysis on the performance measures confirm that the Turbo + CC code in 4×4 configurations exhibits better performance.

Short-term travel flow prediction method based on FCM-clustering and ELM1344-1350

摘要:Short-term travel flow prediction has been the core of the intelligent transport systems(ITS). An advanced method based on fuzzy C-means(FCM) and extreme learning machine(ELM) has been discussed by analyzing prediction model. First, this model takes advantages of ability to adapt to nonlinear systems and the fast speed of ELM algorithm. Second, with FCM-clustering function, this novel model can get the clusters and the membership in the same cluster, which means that the associated observation points have been chosen. Therefore, the spatial relations can be used by giving the weight to every observation points when the model trains and tests the ELM. Third, by analyzing the actual data in Haining City in 2016, the feasibility and advantages of FCM-ELM prediction model have been shown when compared with other prediction algorithms.

Analysis of force and energy density transferred to barrier in a single degree of freedom vibro-impact system1351-1359

摘要:A mass-spring-damper linear oscillator with a limiting stop barrier is presented. Modeling non-smooth processes in mechanical engineering is a complex problem. It is especially for the systems with more than a single degree of freedom. But recent studies in dynamical systems have been applied to single degree of freedom systems. The vibrating system, consisting of an oscillator with amplitude of motion limited by a barrier, is known as a vibro-impact system. The amount of force and kinetic energy transferred to a barrier has an important application in designing of engineering systems that undergo the vibro-impact phenomenon. The results show the effect of changing restitution coefficient of a barrier on the amount of force and energy absorbed.

Design and simulation of electrical dynamometer using improved DTC induction motor driver1360-1368

摘要:AC motors, especially the squirrel cage induction motors have the advantages of simple structure, good reliability and low cost. They are more suitable to be used as electrical dynamometers to provide dynamic load for bench test systems. But, the speed and torque of induction motors are not easy to be controlled accurately. In this work, an electrical dynamometer based on the induction motor is proposed. In order to get better control performance of torque and speed of induction motor, an improved direct torque control method(DTC) is also developed based on the space vector modulation(SVM) technique. The performance of the proposed dynamometer system is validated in the Matlab/Simulink platform. The simulation results show that the new dynamometer has good torque and stator flux response. And the torque and stator current ripples of it are reduced significantly compared with using the conventional DTC method.

Dynamic matrix predictive control for a hydraulic looper system in hot strip mills1369-1378

摘要:Controlling the looper height and strip tension is important in hot strip mills because these variables affect both the strip quality and strip threading. Many researchers have proposed and applied a variety of control schemes for this problem, but the increasingly strict market demand for strip quality requires further improvements. This work describes a dynamic matrix predictive control(DMC) strategy that realizes the optimal control of a hydraulic looper multivariable system. Simulation experiments for a traditional controller and the proposed DMC controller were conducted using MATLAB/Simulink software. The simulation results show that both controllers acquire good control effects with model matching. However, when the model is mismatched, the traditional controller produces an overshoot of 32.4% and a rising time of up to 2120.2 ms, which is unacceptable in a hydraulic looper system. The DMC controller restricts the overshoot to less than 0.08%, and the rising time is less than 48.6 ms in all cases.

Characteristics and mechanism investigation on drag reduction of oblique riblets1379-1386

摘要:This work primarily focuses on the drag reduction characteristics and mechanism investigation of oblique riblets. First, a calculation model of the oblique riblets surface is established, and Reynolds stress model(RSM) turbulence model is used for numerical simulation of the oblique riblets flow field. Subsequently, the influence of inclination angle between flow direction and arrangement direction of riblets on friction resistance and drag reduction rate is further analyzed. Through the investigation of the distribution of shear stress, pressure stress and velocity in oblique riblets boundary layer, the oblique riblets drag reduction mechanism is finally revealed. Results show that, with increase of velocity and inclination angle, the pressure resistance increases obviously, along with the decreasing of the viscous resistance distinctly. The maximum drag reduction rate of the oblique riblets is 7.33%. Moreover, when the inclination angle increases, the wall shear stress reduces on oblique riblets surface; while differential pressure increases at both sides of oblique riblets tips. In addition, when inclination angle is small, the secondary vortex at oblique riblets tips will disappear soon. New vortices will be formed inside the oblique riblets and cause the decrease of viscosity resistance. Thus, oblique riblets show a better drag reduction effect and have an effective control on boundary layer.

Three-dimensional formation keeping of multi-UAV based on consensus1387-1395

摘要:Consensus is an emerging technique using neighbor-to-neighbor interaction to generate steering commands for cooperative control of multiple vehicles. A three-dimensional formation keeping strategy for multiple unmanned aerial vehicles(multi-UAV) is proposed based on consensus, aiming at maintaining a specified geometric configuration. A formation control algorithm with guidance and corresponding flight controllers is given, managing position and attitude, respectively. In order to follow a three-dimensional predefined flight path, by introducing the tracking orders as reference states into the consensus, the formation control algorithm is designed, following the predefined flight path and maintaining geometric configuration simultaneously. The flight controllers are constructed by nonlinear dynamic inverse, including attitude design and velocity design. With the whole system composed of a nonlinear six-degree-of-freedom UAV model, the formation control algorithm and the flight controllers, the formation keeping strategy is closed loop and with full states. In simulation, three-dimensional formation flight demonstrates the feasibility and effectiveness of the proposed strategy.