The effect of right versus left long-term single-sided deafness on sound source localization

Purpose:To analyze the effect of right versus left long-term single-sided deafness(SSD)on sound source localization(SSL),discuss the necessity of intervention and treatment for SSD patients,and analyze the therapeutic effect of long-term unilateral cochlear implantation(UCI)from the perspective of SSL.Methods:This study included 25 patients with SSD,11 patients with UCI,and 30 participants with normal hearing(NH).Their SSL ability was tested by obtaining their average root mean square(RMS)error values of SSL test.Results:The results showed that the RMS error value of SSD,UCI and NH groups were 52.26±20.25◦,69.84±12.14◦and 4.27±2.66◦,respectively.The ability of SSL was better in the SSD-L group than that in the SSD-R group,and no significant difference existed in the SSD-R and the UCI group.Conclusion:When bilateral deafness patients select unilateral treatment,right-side cochlear implantation may be more beneficial in terms of SSL,which means that the central auditory cortex in long-term SSD patients is affected differently based on which side their deafness occurs.

Experimental study on failure characteristics of single-sided unloading rock under different intermediate principal stress conditions

Investigation of unloading rock failure under differentσ_(2)facilitates the control mechanism of excavation surrounding rock.This study focused on single-sided unloading tests of granite specimens under true triaxial conditions.The strength and failure characteristics were studied with micro-camera and acoustic emission(AE)monitoring.Furthermore,the choice of test path and the effect ofσ_(2)on fracture of unloading rock were discussed.Results show that the increasedσ_(2)can strengthen the stability of single-sided unloading rock.After unloading,the rock’s free surface underwent five phases,namely,inoculation,particle ejection,buckling rupture,stable failure,and unstable rockburst phases.Moreover,atσ_(2)≤30 MPa,the b value shows the following variation tendency:rising,dropping,significant fluctuation,and dropping,with dispersed damages signal.Atσ_(2)≥40 MPa,the tendency shows:a rise,a decrease,a slight fluctuation,and final drop,with concentrated damages signal.After unloading,AE energy is mainly concentrated in the micro-energy range.With the increasedσ_(2),the micro-energy ratio rises.In contrast,low,medium and large energy ratios drop gradually.The increased tensile fractures and decreased shear fractures indicate that the failure mode of the unloading rock gradually changes from tensile-shear mode to tensile-split one.The fractional dimension of the rock fragments first increases and then decreases with an inflection point at 20 MPa.The distribution of SIF on the planes changes asσ_(2)increases,resulting in strengthening and then weakening of the rock bearing capacity.

Breathable Electronic Skins for Daily Physiological Signal Monitoring

With the aging of society and the increase in people’s concern for personal health,long-term physiological signal monitoring in daily life is in demand.In recent years,electronic skin(e-skin)for daily health monitoring applications has achieved rapid development due to its advantages in high-quality physiological signals monitoring and suitability for system integrations.Among them,the breathable e-skin has developed rapidly in recent years because it adapts to the long-term and high-comfort wear requirements of monitoring physiological signals in daily life.In this review,the recent achievements of breathable e-skins for daily physiological monitoring are systematically introduced and discussed.By dividing them into breathable e-skin electrodes,breathable e-skin sensors,and breathable e-skin systems,we sort out their design ideas,manufacturing processes,performances,and applications and show their advantages in long-term physiological signal monitoring in daily life.In addition,the development directions and challenges of the breathable e-skin are discussed and prospected.

Elastic Bio-based Polyurethane Nanofibrous Membrane with Robust Waterproof and Breathable Properties

Elastic bio-based waterproof and breathable membranes(EBWBMs) allow the passage of water vapor effectively and resist the penetration of liquid water,making it ideal for use under extreme conditions.In this study,we used a facile strategy to design the bio-based polyurethane(PU) nanofibrous membranes with the nanoscale porous structure to provide the membranes with high waterproof and breathable performances.The optimization of nanofibrous membrane formation was accomplished by controlling the relative ambient humidity to modulate the cooperating effects of charge dissipation and non-solvent-induced phase separation.The obtained EBWBMs showed multiple functional properties,with a hydrostatic pressure of 86.41 kPa and a water vapor transmission(WVT) rate of 10.1 kg·m^(-2)·d^(-1).After 1 000 cycles of stretching at 40% strain,the EBWBMs retained over 59% of the original maximum stress and exhibited an ideal elasticity recovery ratio of 85%.Besides,even after 80% deformation,the EBWBMs still maintained a hydrostatic pressure of 30.65 kPa and a WVT rate of 13.6 kg·m^(-2)·d^(-1),suggesting that bio-based PU nanofibrous membranes could be used for protection under extreme conditions.

Characteristics Investigation of Single-Sided Ironless PMLSM Based on Halbach Array for Medium-Speed Maglev Train

This paper investigates characteristics of ironless permanent magnet linear synchronous motor(PMLSM)based on Halbach array used for medium-speed(200km/h)maglev train.Long primary ironless coil is laid in the middle of track and the Halbach permanent magnet array is attached to the bottom of each bogie as a source of traction,U-shape electromagnets at the both sides of the train for levitation.Two dimensional analytical model of single-sided ironless PMLSM based on Halbach array is established,using linear overlay method,the no-load air gap magnetic field is calculated firstly,winding current density distribution is obtained for calculating the characteristics of thrust and normal force against power angle,including force characteristics with equal and unequal pole pitch,the influence of steel sleeper,etc.Besides,the mathematical model for this type motor is built by 3D finite element method,the traction characteristics of medium-speed maglev under maximum speed 200km/h are calculated.The characteristics of this type motor are satisfactory owing to there is no detent force in the motor and thrust force reach maximum meanwhile normal force can be eliminated.Calculation method is verified by comparing finite element results,experimental result on a 200kW type motor further validates the accuracy of calculation and some important conclusions are obtained.

Condensation of Water Vapor on Waterproof Breathable Fabrics

Condensation occurs when the local vapor pressure rises above the saturation vapor pressure at the local temperature in theory. A new measuring apparatus were made to obtain temperature and relative humidity simultaneously for the purpose of investigating the mechanism of condensation occurred on the fabrics. The experiment conducted at the standard condition of temperature of 20℃ and relative humidity of 65%. The result obtained from experiment showed that condensation could occur under the situation closed to saturation line as the temperature on fabric may be lower than dew point of water vapor in the measuring box depending on the experiment conducted at an ambient environment temperature of 20℃ The range of fabrics studied showed that PTFE laminated fabrics except nylon gingham PTFE laminated fabric facilitates the loss of water vapor and therefore prevent condensation. It is necessary to develop studies from a wide range of fabrics, especially breathable fabrics and under bad experiment condition in order to develop fabrics, which could eliminate condensation, or transport water vapor through the fabric while remaining waterproof.

Adaptive current compensation with nonlinear disturbance observer for single-sided linear induction motor considering dynamic eddy-effect

An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideration of the specially dynamic eddy-effect(DEE) of the SLIM, a instantaneously tracing compensation of m-axis current component was analyzed. Second,adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer(NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.

Measurement of thermal conductivity of materials using single-side TPS technique

Based on the traditional measurement theory of transient plane source (TPS) technique, single-side TPS method is proposed for measuring the thermal conductivity of single specimen. The problem of transient heat conduction in a semi-infinite boundary condition is studied and the theoretical formula of single-side TPS method is deduced. During the measurement, the influence of the probe heat capacity on the results is analyzed and the corresponding mathematical compensation model is established, and a series of experiments on different materials are conducted by hot disk probe at normal temperature and pressure. The results show that the relative error with the single-side TPS method is less than 5% and the relative standard deviation is no greater than 3%. This method has high accuracy and good reproducibility, which provides a feasible measuring method for single material that does not meet the requirements of the standard TPS theory.

Experimental Investigation of Defects Inspection for FRP Pipeline based on Single-side NMR

The fiberglass reinforced plastic （FRP） pipelines have been used widely in oil-gas gathering and transportation. The defects of FRP pipelines would increase with the extension of service time. However, it is very difficult to detect the defects of FRP pipelines on-spot quickly. In this paper, a new method detecting defects for FRP pipes has been provided based on the NMR. The proton density distributions have been obtained at different depth of FRP components using single-side NMR. The experimental results show that there is a significant change of proton density distribution at the location of defects. And, these results would be useful for defects inspection of composite material component.

隔水透气隔断层对寒旱区盐渍土水盐迁移及变形特性的影响

针对寒旱区盐渍土水盐迁移引起的盐冻胀变形病害问题,本研究提出了一种新型的隔水透气膜隔断层处理方法,并开展了相应的理论分析和室内试验研究。基于多孔介质理论和连续介质力学理论,通过考虑温度变化下孔隙水盐相变等因素,建立了非饱和盐渍土的水-热-盐-力多场多相耦合模型。在水盐补给条件下,采用数值模拟和室内模型试验研究了非饱和硫酸盐渍土的水盐迁移和盐冻胀变形特性,并验证了模型的有效性。重点分析了设置隔水透气膜对非饱和硫酸盐渍土热质迁移及变形行为的影响。研究结果表明:隔水透气层对液态水和溶解盐的迁移具有明显的阻滞作用。同时,由于隔断层的透气特性,可有效地解决传统土工膜隔断层下气体聚集现象。研究成果可为盐渍土路基处理提供技术与理论基础。

防水透湿性老年心脏监测服装的创新设计

随着现代信息技术的发展,智能化、智慧化趋势显著,广泛渗透于老年服装设计等领域,为服装设计践行以人为本的理念、提升老年人生存质量、解决老年群体关怀护理难题提供了新思路。面对老年用户对心脏监测服装防水透湿功能的现实需求,文章遵循良好的力学性能、界面相容性、绿色环保性、耐磨耐用性、符合老年人审美5项原则,考量人机、面料、结构、细节4类要素,开发、测试老年心脏监测服装防水透湿膜,并以此为材料设计防水透湿性老年心脏监测服装,以期为老年智能服装设计提供有益启示,满足老龄化社会消费市场需求。

焦炭反应性对块矿高炉冶金性能的影响研究

研究焦炭反应性对块矿在高炉中的熔滴性能和滴落物质量等冶金性能的影响,可全面解析不同反应性的焦炭在高炉内的实际劣化情况,为完善焦炭综合评价指标体系提供技术支撑。通过铁矿石荷重还原滴落性能实验检测装置,在CO_(2)/N_(2)体积分数比为30%∶70%条件下,研究5种不同热态反应性的焦炭以及混装焦炭对高炉操作和滴落物质量的影响。研究结果表明:焦炭反应性从22.0%升至50.2%,软化温度逐渐减小,软熔带增厚;当焦炭反应性小于35%时,随着反应性的增加则压差陡升温度降低、透气性变差,同时滴落物中会逐渐出现难还原的Fe2SiO_(4)和未彻底还原的FeO,滴落物中焦粉含量也逐渐增加;当焦炭反应性大于35%时,随着反应性的增加则压差陡升温度升高,透气性得到改善,难还原的Fe_(2)SiO_(4)和未彻底还原的FeO逐渐减少,滴落物中焦粉含量也逐渐减少。按一定比例搭配的混装焦炭在减小软熔带厚度、改善透气性、减少滴落物中焦粉含量等方面优于单一热态性质的焦炭。

印花织物结构性能与持续凉感作用机理研究

测试评价了6种印花织物的结构性能,包括表面形貌、透气性、浸润性、湿态贴体粘附性以及涂层的耐洗牢度和耐磨性,分析了出汗后印花织物的持续凉感作用机理。结果表明:印花涂层呈现出颗粒状且印花并未完全覆盖纤维,因而印花对织物的透气性几乎没有影响;织物的接触角表明印花涂层具有一定的疏水性,经过印花后织物的芯吸高度增加且湿态贴体粘附性下降,印花涂层具有很好的耐磨性和耐水洗牢度,拍摄的红外热成像表明经过印花后织物的持续凉感效果得到了加强,300 s后印花织物表面的温度降低了1℃~2℃,这是由于出汗后一部分汗液会沿着印花部分的缝隙渗透到织物表面蒸发,产生凉感,而另一部分汗液则会以小水滴的形式存在于印花部分进而给织物带来凉感。

不同包装形式对大米-小麦混合粉馒头贮藏品质的影响

为探究大米-小麦混合粉馒头的最佳包装形式和贮藏方式,通过分析馒头中微生物含量、水分含量、质构特性及复蒸后感官特性,揭示透气包装、脱氧包装和密封包装在25℃和4℃贮藏条件下对大米-小麦混合粉馒头品质的影响。研究发现,透气包装馒头的水分含量、弹性的下降速率和硬度的上升速率最快,感官评分最低;整个贮藏中脱氧包装馒头的水分含量和硬度略小于密封包装馒头,弹性大于密封包装馒头。在25℃贮藏时透气包装、脱氧包装和密封包装馒头分别在1、6、3 d时菌落总数超过6 lg CFU/g;2、5、4 d时霉菌数超过标准GB/T 21118-2007200 CFU/g,1、3、5 d时出现感观品质劣变。在4℃贮藏时密封包装、脱氧包装和透气包装馒头分别在8、14、12 d时菌落总数超过6 lg CFU/g,10、12、10 d时霉菌数超过标准GB/T 21118-2007200 CFU/g,8、12、10 d时出现感观品质劣变。因此,采用脱氧包装的低温贮藏形式使馒头具有较好的贮藏品质。

运动服饰的透气性与耐用性分析

随着人们运动意识和健康意识的提升,运动服饰不仅需要满足美观需求,而且需要满足透气性和耐用性等功能性要求,从而保证运动效果和穿着舒适度。不同的面料、技术、制造工艺都会对运动服饰的透气性和耐用性产生影响,所以设计师必须综合考虑运动需求、面料属性等因素,设计符合运动要求的服装。探讨运动服饰的透气性与耐用性,为运动服饰设计提供参考。

复合改性纤维基调湿材料吸放湿性能研究

以主要成分为植物纤维的纤维片材作为调湿材料的基材,利用无机盐的高吸湿性对纤维片材进行改性,以改善其调湿能力。为了减少无机盐的流失,采用高吸水性树脂和防水透气膜对纤维片材进行了复合。在恒温恒湿箱中对原材料和复合纤维片材进行了吸湿和放湿试验,并测试了复合纤维片材的盐流失性。结果表明,氯化钠可以提升纤维片材的吸放湿性能,但盐流失率较大;高吸水性树脂和防水透气膜的复合可有效减少纤维片材中无机盐的流失,其中采用高吸水性树脂复合纤维片材具有良好的调湿性能,且盐流失率较小。

基于GRA-GA-BP神经网络的家居服面料透气性能预测

本文构建了一种改进BP神经网络模型来预测家居服面料的透气性能,能为家居服设计提供重要的参考。首先,采用灰色关联分析法(Grey Relation Analysis,GRA),选择与透气率关联度较大的因素作为研究对象。其次,采用遗传算法(GA)优化BP神经网络的结构参数,构建基于灰色关联分析的遗传算法优化BP(GRA-GA-BP)神经网络预测模型。选取58种面料成分不同、织物组织各异的家居服面料,其中42种为模型训练样本,16种为测试样本对建立的模型进行验证。实验结果表明,透气率实测值与预测值平均相对误差为8.39%;对透气率实测值与预测值进行相关性分析,拟合优度R^(2)为0.976。研究表明,该预测模型预测效果良好、预测精度高,在一定程度上可以精准预测家居服面料的透气率。

透气凉爽丝麻面料的制备及其性能

为了开发出在炎热条件下穿着舒适、透气性能好、触感凉爽的高端服用面料,采用桑蚕丝作为经纱,大麻(汉麻)纱作为纬纱,在相同的经密下,通过改变织物组织、纬密及经纬组织点等方法,设计并试织了A、B、C三个系列共24种织物,利用织物透气量仪和Hot Disk热常数分析仪分别测试织物的透气和导热系数,并通过模糊综合分析法对各项数据指标进行分析。结果表明:在经密为50根/(10 cm)、纬密为30根/(10 cm)、组织为8枚纬缎时,丝麻面料的透气性、凉爽性能最好;在经密不变、纬密增加时,丝麻面料的透气性、凉爽性下降;随着缎纹经组织点的个数的增加,丝麻面料的透气性、凉爽性会下降;当纬密增加且组织为平纹和斜纹时,丝麻面料的透气性、凉爽性会增加。研究结果可为进一步开发具有透气性、凉爽性高端功能服用面料提供一定的理论参考。

Comparison of the performance and dynamics of the asymmetric single-sided and symmetric double-sided vibro-impact nonlinear energy sinks with optimized designs

The operation of symmetric double-sided and asymmetric single-sided vibro-impact nonlinear energy sinks(DSVI NES and SSVI NES)is considered in this study.The methodology of optimization procedures is described.It is emphasized that the execution of optimization procedures is ambiguous,allows for a great deal of arbitrariness,and requires experience and intuition on the part of the implementer.There are a lot of damper parameter sets providing similar attenuation of the primary structure(PS)vibrations.It is shown that the efficiency of such mitigation for both VI NES types with optimized parameters is similar.However,their dynamic behavior differs significantly.The system with the attached DSVI NES exhibits calm dynamics with periodic motion and symmetrical bilateral impacts on both obstacles.The system with attached SSVI NES exhibits rich complex dynamics when the exciting force frequency is varied.Periodic modes of different periodicity with different numbers of asymmetric impacts per cycle on the PS directly and on the obstacle alternate with various irregular regimes,namely,chaotic mode,intermittency,and crisis-induced intermittency.The regions of bilateral impacts are narrow and located near resonance;they are narrower for a system with an attached DSVI NES.In a system with an attached SSVI NES,there are wider areas of asymmetric unilateral impacts.

无溶剂聚氨酯防水透湿膜的制备及性能研究

以聚乙二醇(PEG)、聚四氢呋喃二醇(PTMG)、1,4-丁二醇、乙二醇、流平及润湿性助剂为A组分,以聚丙二醇(PPG)、PEG与4,4′-二苯基甲烷二异氰酸酯(MDI-100)制备的预聚体为B组分,将A、B组分混合制备无溶剂聚氨酯(PU)防水透湿膜。讨论了流平及润湿性助剂对防水透湿膜平整性的影响,并考察了A组分中PEG/PTMG质量比对薄膜表观形貌、热稳定性、力学性能和防水透湿性的影响。结果表明,流平剂及润湿剂质量分数分别为1%和0.5%、A组分中PEG/PTMG质量比为7∶3时,PU防水透湿膜的拉伸强度为19.8 MPa,透湿度为14 200 g/(m^(2)·d),耐水压>90 kPa,膜表面平整致密,综合性能较好,可满足其在防水透湿领域的应用。