Influence of expanded polystyrene size on deformation characteristics of light weight soil

Deformation characteristics of light weight soil with different EPS (expanded polystyrene) sizes were investigated by consolidation tests.The results show that the confined stress-strain relation curve is in S shape,which has a good homologous relation with e-p curve and e-lgp curve,and three types of curves reflect obvious structural characteristics of light weight soil.When cement mixed ratio and EPS volume ratio are the same for different specimens,structural strength decreases with the increase of EPS size,but compressibility indexes basically keep unchanged within the structural strength.The settlement of light weight soil can be divided into instantaneous settlement and primary consolidation settlement.It has no obvious rheology property,and 90% of total consolidation deformation can be finished in 1 min.Settlement-time relation of light weight soil can be predicted by the hyperbolic model.S-lgt curve of light weight soil is not in anti-S shape.It is proved that there is no secondary consolidation section,so consolidation coefficient cannot be obtained by time logarithm method.Structural strength and unit price decrease with the increase of EPS size,but the reducing rate of the structural strength is lower than that of the unit price,so the cost of mixed soil can be reduced by increasing the EPS size.The EPS beads with 3-5 mm in diameter are suggested to be used in the construction process,and the prescription of mixed soil can be optimized.

Light weight analysis of a skeleton vehicle frame using BS960 super-high-strength steel

Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle＇s frame. Results indicated that the maximum stress occurs on the front beam ＇s variable section area. Dynamic sensitivity analysis elucidated the relationship between the maximum stress and the thickness of a particular beam,e. g.,top,middle,and bottom beam. Displacement was analyzed by the key part that influenced the maximum stress. Finally,the new plan using BS960 super-high-strength beam steel and the preferred beam thickness was compared with the original plan. New combinations of beam thickness were introduced on the basis of different purposes; the maximum responding light w eight ratio was 21%.

Neuro-fuzzy systems in determining light weight concrete strength

The adaptive neuro-fuzzy inference systems(ANFIS)are widely used in the concrete technology.In this research,the compressive strength of light weight concrete was determined.To this end,the scoria percentage and curing day variables were used as the input parameters,and compressive strength and tensile strength were used as the output parameters.In addition,100 patterns were used,70%of which were used for training and 30%were used for testing.To assess the precision of the neuro-fuzzy system,it was compared using two linear regression models.The comparisons were carried out in the training and testing phases.Research results revealed that the neuro-fuzzy systems model offers more potential,flexibility,and precision than the statistical models.

Development of Light Weight Structures to Provide Blast-Resistant Designs

In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.

Bond Strength of Bamboo Reinforcement in Light Weight Concrete

Bamboo reinforced concrete as a building material is expected to be an alternative to steel reinforced concrete. Due to the fact that steel is not renewable and polluting steel mills are fairly high. The bond strength is a major concern for the natural fiber used as reinforcement in structural composites. This paper reports study on the bond strength of bamboo reinforcement in concrete, to determine the adhesion reinforcement in concrete often do by the pull-out test. The research objective was bond strength of lightweight concrete and bamboo reinforcement. The test used light weight concrete with foam additives klerak. Bamboo slats were coated with paint and sprinkled with sand. The results obtained showed that the bond strength bamboo 60% of the bond strength steel.

Comparison of Low Stress Mechanical Properties of Light Weight Wool and Wool Blend Fabrics using the KES-F and FAST Instruments

This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter.

Experimental Investigation and Development of Artificial Neural Network Model for the Properties of Locally Produced Light Weight Aggregate Concrete

The developments in the field of construction raise the need for concrete with less weight. This is beneficial for different applications starting from the less load applied to foundations and soil till the reduction of carnage capacity required for lifting precast units. In this paper, the production of light weight concrete from light local weight aggregate is investigated. Three candidate materials are used: crushed fired brick, vermiculite and light exfoliated clay aggregate (LECA). The first is available as the by-product of brick industry and the later two types are produced locally for different applications. Nine concrete mixes were made with same proportions and different aggregate materials. Physical and mechanical properties were measured for concrete in fresh and hardened states. Among these measured ones are unit weight, slump, compressive and tensile strength, and impact resistance. Also, the performance under elevated temperature was measured. Results show that reduction of unit weight up to 45%, of traditional concrete, can be achieved with 50% reduction in compressive strength. This makes it possible to get structural light weight concrete with compressive strength of 130 kg/cm2. Light weight concrete proved also to be more impact and fire resistant. However, as expected, it needs separate calibration curves for non-destructive evaluation. Following this experimental effort, the Artificial Neural Network (ANN) technique was applied for simulating and predicting the physical and mechanical properties of light weight aggregate concrete in fresh and hardened states. The current paper introduced the (ANN) technique to investigate the effect of light local weight aggregate on the performance of the produced light weight concrete. The results of this study showed that the ANN method with less effort was very efficiently capable of simulating the effect of different aggregate materials on the performance of light weight concrete.

Time Dependent Surface Heat Transfer in Light Weight Aggregate Cement Based Materials

Surface temperature changes of building materials affect the calculation of heat flow and thus the energy use in heating and cooling. The surface heat transfer coefficient , limiting the heat flow between material surface and ambient air is normally taken as a constant. In this study we propose a time-dependent function . We estimate from unidirectional heat flow experiments with transient and steady-state conditions. Using temperature measurements and the conservation of energy at the surface including convective and irradiative boundary conditions, the value of was obtained both using Finite Difference and Taylor Polynomials methods. Numerical solutions of temperature distribution as function of time were improved with the obtained -functions compared to with constant . There were no clear difference between on different materials, and the final values observed were in the order of magnitude expected from the literature.

Experimental-mechanistic analysis of pavement base deflections measured with light weight deflectometer

An extensive experimental-mechanistic study was conducted to reveal the relationship between the light weight deflectometer(LWD)measured deflections and the degree of compaction of pavement base materials.Both laboratory experiments and test pits experiments were performed with different types of pavement base materials.The modulus based maximum allowable LWD deflections under different structural and compaction conditions were developed for the most commonly used pavement base aggregate in Indiana.The maximum allowable deflections are based on the equivalent subgrade modulus and the thickness of the layer to be compacted.It is emphasized that the LWD deflections must be measured as soon as the material is compacted or before the moisture content decreases beyond a specified range.Therefore,the maximum allowable deflections are specified in terms of the difference between the actual moisture content and the optimum moisture content.The maximum allowable deflection values provide a sound basis for compaction quality control using LWD devices.

基于时段敏感权重组合的LightGBM和LSTM冷负荷预测方法

冷负荷预测是中央空调系统节能控制的基础。为进一步提升冷负荷预测的精度,提出了加权组合轻梯度提升机(LightGBM)模型和长短期记忆(LSTM)网络的预测方法,并在不同时段分配不同权重。首先,对冷负荷数据、室外温度、室外湿度进行数据预处理,分别按照LightGBM模型和LSTM网络的输入格式进行输入训练;其次,对验证集上的评估结果进行超参数调整,再将验证集划分为不同时段,使用最优化算法获得各时段最优的组合权重;最后,使用实际冷负荷数据进行算例分析。结果表明,所提方法能在不同时段有效利用2种模型的优点,具有较高的预测精度。

Light weighting opportunities and material choice for commercial vehicle frame structures from a design point of view

This paper focuses on an estimation of light weighting opportunities for the frame structure of com- mercial road vehicles. This estimation is based on simpli- fied static load cases which play a predominant role for the dimensioning of a frame structure and therefore these simplifications are not putting the general validity of the conclusions into question. A comparison of different ma- terials under this scenario shows that light metals do not show any weight reduction advantage in comparison to steel while a material-independent topology optimization has more weight reduction potential for the frame structure than a simple change of materials. Considering the con- straints of part complexity which is directly linked with production and assembly cost, the ladder frame structure has become the current state of the art design. Thus the paper also puts a spotlight on basic rules of node design and vertical load induction in order to keep the weight of such a design as low as possible. Practical examples from manufacturers show that the weight of a commercial vehicle could be reduced by 10%, and main parts of the frame structure could be reduced by 30% using high strength steel in combination with innovative production methods like roll forming.

基于Multi-Light模型的奶牛个体识别研究

为了解决大规模智能化奶牛养殖场对奶牛个体识别存在模型大、识别速度慢的问题,试验构建了一种用于识别奶牛个体的多尺度轻量化卷积神经网络(Multi-Light)模型,将拍摄的奶牛图像经过标注后利用DeepLab V3模型从复杂背景中分割出单头奶牛图像;在Multi-Light模型中引入空洞卷积,保证该模型参数量不变的同时增强提取图像全局信息的能力;加入多尺度卷积模块增强该模型对不同尺度特征点的检测能力,在该模型中使用短路连接以保证特征不丢失,提升模型的识别精度;此外,利用通道注意力机制提高了该模型识别精度,同时使该模型具有更多的非线性;最后将分割得到的奶牛图像数据集输入Multi-Light模型进行训练。结果表明:Multi-Light模型对奶牛个体识别的精度达98.51%,高于其他经典模型对奶牛个体的识别率;与轻量级模型对比,Multi-Light模型的大小为5.86 MB,在具备高识别精度的前提下参数量较少。说明试验所搭建的Multi-Light模型克服了传统方法中需要对特征进行人为提取、提取特征方法不够鲁棒、识别模型参数量大及识别速度慢的缺点,为奶牛个体轻量化识别提供了参考。

Light-Weight Design Method for Force-Performance-Structure of Complex Structural Part Based Co-operative Optimization

A light?weight design method of integrated structural topology and size co?optimization for the force?performance?structure of complex structural parts is presented in this paper. Firstly, the supporting function of a complex structural part is built to map the force transmission, where the force exerted areas and constraints are considered as connecting structure and the structural configuration, to determine the part performance as well as the force routines. Then the connecting structure design model, aiming to optimize the static and dynamic performances on connection configuration, is developed, and the optimum design of the characteristic parameters is carried out by means of the collaborative optimization method, namely, the integrated structural topology optimization and size optimization. In this design model, the objective is to maximize the connecting stiffness. Based on the relationship between the force and the structural configuration of a part, the optimal force transmission routine that can meet the performance requirements is obtained using the structural topology optimization technology. Accordingly, the light?weight design of conceptual configuration for complex parts under multi?objective and multi?condition can be realized. Finally, based on the proposed collaborative optimization design method, the optimal performance and optimal structure of the complex parts with light weight are realized, and the reasonable structural unit configuration and size charac?teristic parameters are obtained. A bed structure of gantry?type machining center is designed by using the proposed light?weight structure design method in this paper, as an illustrative example. The bed after the design optimization is lighter 8% than original one, and the rail deformation is reduced by 5%. Moreover, the lightweight design of the bed is achieved with enhanced performance to show the effectiveness of the proposed method.

Preparation of Light-weight Spinel Refractories by Foaming-gel Process

Light-weight magnesium -aluminate spinel materi- als were prepared by foaming-gel process with polyalumi- nium chloride （PAC） as gel. Effect of solid loading in initial slurry on microstructure, porosity, pore size distri- bution, thermal conductivity and mechanical properties was investigated. The results show that the bulk density of the light-weight magnesium -aluminate spinel mate- rials is in the range of O. 7 1.2 g cm-3 ; pore size distribution curves show single-peak characteristics and the mean pore size is in the range of 30. 83 - 61.37 μm ; with the increase of solid loading, the linear shrinkage of the green body during firing and the permanent change in dimensions on heating at l 600 ℃ for 3 h de- crease, but the bulk density increases, the mechanical properties increase obviously; the maximum compressive strength and bending strength reach 35. 25 MPa and 9. 92 MPa, respectively, while the bulk density is 1. 16 g · cm ; and the thermal conductivity at 1 000 ℃ tea- ches 0. 371 W · m-1 . K-1 while the bulk density is O. 7 -3 g · cm

Long-Term Continuous Light Exposure Affects Body Weight and Blood Glucose Associated with Inflammation in Female Rats

Studies have indicated that night lights interfere with the circadian rhythm in the human body and threaten human health. Our previous studies indicated that continuous light exposure severely damages the reproductive endocrine system of female rats resembles polycystic ovary syndrome in women. In this study, we used the continuous measurement method to observe changes in the basal physiological indicators of female rats in an abnormal light exposure environment. Our study results indicated that in female rats: 1) the body temperature first continuously and gradually increased followed by a gradually decrease;2) the increase in body weight slowed down at the late stage of the experimental process;3) the random blood glucose level increased, and the fasting serum insulin level decreased;and 4) the serum C-reactive protein level increased. Our study investigated for the first time the correlation between the duration of continuous light exposure in female rats and the continuously measured basal physiological indicators and preliminarily discussed the effect of continuous light exposure on female basal metabolism and the possible inflammation mechanism. We propose that long-term continuous exposure to night lights in females severely damages their immune and metabolic systems.

Principles and Chief Technologies in Developing Light-weighted Worsted Fabrics

More and more light-weighted fabrics are being required by the market, especially for the worsted manufacture.In the past, such fabrics are produced mainly through changing the structure of woven goods or by using finer yarns. But these possibilities are very limited. In this paper, new devices are discussed: (1) on the yarn level- to use single yarns instead of conventional doubled ones, to decrease number of fibers in yarn cross sections beth during spinning and after finishing; (2) on the fiber level - to use finer fibers in blends with wool and modification of the wool fibers; (3) on the macromolecule level - to stretch the macromolecules in alpha keratin, to get super fine wool fibers.

Ultra-thin and light-weight spoof surface plasmon polariton coupler achieved by broadside coupled split ring resonators

Low profile and light weight are very important for practical applications of a spoof surface plasmon polariton（SSPP）coupler, especially at low frequencies. In this paper, we propose and design an ultra-thin, light-weight SSPP coupler based on broadside coupled split ring resonators（BC-SRRs）. The size of BC-SRR can be far less than λ/100 and can extremely well control the reflective phases within a subwavelength thickness. Due to the broadside capacitive coupling, the electrical size of BC-SRR is dramatically reduced to guarantee the ultra-thin thickness of the SSPP coupler. The weight of the SSPP coupler is reduced by a low occupation ratio of BC-SRR in the unit cell volume. As an example, a C-band SSPP coupler composed of phase gradient BC-SRRs is designed, fabricated, and measured. Due to the ultra-small size and low occupation ratio of BC-SRRs, the thickness of the coupler is λ/12 and the surface density is only 0.98 kg/m^2. Both simulation and experiment results verify that the coupler can achieve high-efficiency SPP coupling at 5.27 GHz under normal incidence.

Effect of Commercial Synthappret BAP Treatment on the Tailorability of Light-Weight Worsted Wool Fabrics

By means of measurement with the FAST instruments, the effect of commercial Synthappret BAP treatment on the tailorability of light-weight wool worsted fabrics has been investigated. It was found that the commercial Synthappret BAP treatment unproved the tailorability of the light-weight wool fabrics mainly by increasing the bending stiffness of the light-weight wool fabrics.

Effects of Spherical Light-weight Aggregates Additions on Workability and Mechanical Properties of Al_2O_3-SiO_2 System Castables

In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-weight aggre- gates, bauxite homogenization powder, microsilica , cal- cium aluminate cement as main raw materials, light- weight Al2 03 - SiO2 system castables were prepared by replacing conventional light-weight aggregate with spherical light-weight aggregates. The effects of spheri- cal light-weight aggregates addition on workability, me- chanical properties of castables after heated at different temperatures were researched; the microstructure of the aggregates was analyzed by SEM. The result shows that the introduction of spherical light-weight aggregates can significantly improve the flowability and reduce the water addition of the castables. Water demand of the castable is reduced from 18% with the conventional light-weight aggregates to 14% with spherical light-weight aggre- gates. In addition, light-weight castables prepared by spherical aggregates can keep the same workability with- in a wider range of water addition. Therefore, spherical aggregates are user-friendly. The introduction of spheri- cal light-weight aggregates is favorable to packing densi- ty and mechanical properties of castables, such as cold crushing strength, cold modulus of rupture, hot modulus of rupture at 1 200℃.

A Study of Thermal Response and Flow Field Coupling Simulation around Hayabusa Capsule Loaded with Light-Weight Ablator

The numerical simulation of flow field around Hayabusa capsule loaded with light-weight ablator thermal response coupled with pyrolysis gas flow inside the ablator was carried out. In addition, the radiation from high temperature gas around the capsule was coupled with flow field. Hayabusa capsule reentered the atmosphere about 12 km/sec in velocity and Mach number about 30. During such an atmospheric entry, space vehicle is exposed to very savior aerodynamic heating due to convection and radiation. In this study, Hayabusa capsule was treated as a typical model of the atmospheric entry spacecraft. The light-weight ablator had porous structure, and permeability was an important parameter to analyze flow inside ablator. In this study, permeability was a variable parameter dependent on density of ablator. It is found that the effect of permeability of light-weight ablator was important with this analysis.