AGW482滚刀磨床的砂轮修形原理

文中分析了 AGW482滚刀磨床的砂轮修形原理,并根据优化设计的原则,建立了确定修形装置调整参数的数学模型。对于连续光滑的砂轮轴截形,都可由此模型计算出修形装置的最优调整参数。     

用磁选柱精选齐大山选矿厂磁选中矿的试验研究

介绍了用磁选柱选别齐大山选矿厂磁选中矿的实验室研究。试验证明：磁选柱可有效地将磁铁矿连生体颗粒从磁铁矿精矿中分选出来,从而获得高品位的铁精矿。     

服装试衣系统中三维模特姿态服饰识别算法

提出了基于三维视图的模特姿态服饰识别算法技术。首先基于一元高次多项式最小函数二乘拟合方法，由单视图通过变形生成三维视图的模特姿态服饰图像，然后基于该单视图和生成的三维视图进行模特姿态服饰图像识别。最后根据整个训练数据样本库，通过基于三维视图和融合决策的识别算法进行服饰识别，实验结果表明本算法比仅仅基于单视图作为训练样本库的模特姿态服饰识别算法的正确率有了很大提高。     

中韩两国青年女性着装意愿与行为比较

以中国江苏省和韩国首尔地区20~25岁青年女性为调查对象,采用问卷调查方式,就中韩两国青年女性对服装造型及不同款式搭配、适体性与长短款变化等款式形态偏爱程度和着装习惯等进行了调查.使用SPSS17.0统计软件,运用描述分析、均值比较、相关分析等统计方法,对中韩两国青年女性着装意愿和着装行为等进行了分析比较.研究结果表明,韩国女性对于紧身凸显体型和身体暴露面积大的服装偏爱度高于中国,中韩两国女性对于宽松型服装的穿着频率都高,这些结论为中韩两国服装行业的产品设计和贸易提供了较有价值的参考信息.     

Chitosan-polyvinyl alcohol membranes with improved antibacterial properties contained Calotropis procera extract as a robust wound healing agent

Due to excessive use of antibiotics, resistance against microorganisms is developed. An alternative use of antibiotics, natural remedies from plants have been used against infectious diseases. In the current study, bioactive compounds from Calotropis procera (C. procera) root were extracted and chitosan and polyvinyl alcohol (CS-PVA) were used asa carriers and for the delivery to treat induced infection. Different concentration of C. procera extracts (25–75 mg/mL) were loaded on CS-PVA membrane and applied on the induced wounds in rabbits. Wound reduction was recorded for 12 days. On 6th day, small tissue from healing area were collected and subject to histopathology for tissue regeneration. The antioxidant activity (DPPH, TPC and TFC) was also investigated of CS-PVA loaded C. procera root extract. The DPPH free radical inhibition for 75 mg/mL were recorded up to 66.37%. The TPC and TFC contents were recorded to be 36.52 ± 5.12 GAE mg/g of DW (dry weight) and 24.49 ± 6.27 CE mg/g of DW (dry weight), respectively. The antibacterial activity was evaluated against Escherichia coli and Staphylococcus aureus in comparison to control (Rifampicin). The zones of inhibition were recorded to be 18.50 ± 2.30 and 20.40 ± 4.20, respectively for CS-PVA membrane loaded with 75 mg extracts along with Rifampicin 28.50 ± 2.5 and 30.50 ± 1.38. The CS-PVA membranes were also studied for swelling and biodegradability. The biodegradability was increased, while swelling was decreased of CS-PVA membranes loaded with extract. The bioactive compounds from the CS-PVA loaded with extract released in controlled and sustainable way. Result revealed that CS-PVA loaded C. procera root extract has promising antimicrobial and antioxidant activity and could possibly be employed for the treatment of infectious diseases.     

Chitosan-Placental ECM Composite Thermos-Responsive Hydrogel as a Biomimetic Wound Dressing with Angiogenic Property

Attempts are being made to develop an ideal wound dressing with excellent biomechanical and biological properties. Here, a thermos-responsive hydrogel is fabricated using chitosan (CTS) with various concentrations (1%, 2.5%, and 5% w/v) of solubilized placental extracellular matrix (ECM) and 20% β-glycerophosphate to optimize a smart wound dressing hydrogel with improved biological behavior. The thermo-responsive CTS (TCTS) alone or loaded with ECMs (ECM-TCTS) demonstrate uniform morphology using SEM. TCTS and ECM1%-TCTS and ECM2.5%-TCTS show a gelation time of 5 min at 37 °C, while no gel formation is observed at 4 and 25 °C. ECM5%-TCTS forms gel at both 25 and 37 °C. The degradation and swelling ratios increase as the ECM content of the hydrogel increase. All the constructs show excellent biocompatibility in vitro and in vivo, however, the hydrogels with a higher concentration of ECM demonstrate better cell adhesion for fibroblast cells and induce expression of angiogenic factors (VEGF and VEGFR) from HUVEC. Only the ECM5%-TCTS has antibacterial activity against Acinetobacter baumannii ATCC 19606. The data obtained from the current study suggest the ECM2.5%-TCTS as an optimized smart biomimetic wound dressing with improved angiogenic properties now promises to proceed with pre-clinical and clinical investigations.     

Studies of dynamics of a lightweight wheeled mobile robot during longitudinal motion on soft ground

The paper is concerned with the study of longitudinal motion of a lightweight wheeled mobile robot on soft ground. The study is focused on the influence of the desired longitudinal velocity of a robot on both the longitudinal slip of the wheels and the ratio of wheel-terrain contact angles. Design of the four-wheeled skid-steered robot and research environment are described. Experimental investigations were conducted on a dedicated test stand with dry sand. A dynamics model of the robot-ground system taking into account properties of soft ground is presented. The classical terramechanics models of Bekker and Janosi-Hanamoto are used. Results of simulation research of robot motion and of the analogous experimental investigations are presented. Actual motion parameters of the robot and the values of longitudinal slip ratio of the wheels are determined. The results of simulation and experimental investigations are compared and discussed. A formula to describe front-to-back wheel-terrain contact angle ratio dependency on the desired velocity is proposed.     

Isolated large amplitude periodic motions of towed rigid wheels

This study investigates a low degree-of-freedom (DoF) mechanical model of shimmying wheels. The model is studied using bifurcation theory and numerical continuation. Self-excited vibrations, that is, stable and unstable periodic motions of the wheel, are detected with the help of Hopf bifurcation calculations. These oscillations are then followed over a large parameter range for different damping values by means of the software package AUTO97. For certain parameter regions, the branches representing large-amplitude stable and unstable periodic motions become isolated following an isola birth. These regions are extremely dangerous from an engineering point of view if they are not identified and avoided at the design stage. Research Group on Dynamics of Machines and Vehicles, Hungarian Academy of Sciences.