基于RGB视觉的瓦楞包装褶皱标定收敛研究

目的 对瓦楞纸板包装的褶皱特征精确定位,保证瓦楞纸板包装容器的褶皱特征在生产中被及时检验。方法 机器视觉瓦楞纸板包装检测系统依据图像信息收集、识别算法、RGB视觉、位置标定、收敛性结果对比等部分,确定瓦楞纸板包装褶皱特征标定核心算法要点;在传统频域变换的基础上,进行RGB视觉改进算法分析,有效提高对瓦楞纸板包装的褶皱特征识别率,明确该类包装的检测要点。以实际的瓦楞纸板褶皱为例,论证该类包装褶皱特征的特征提取方法,并且强化研究对象的褶皱特征,最后对识别结果和实物结果进行对照分析。结果 通过设定阙值在90～120得到线性率为25%～80%,结果说明该视觉方式可以实现对机器视觉的瓦楞纸板包装标定,并且各特征的实际回归基准率为86%,验证了RGB视觉算法对褶皱特征标定的精确性。结论 基于该RGB视觉以及优化措施,确定了机器视觉瓦楞纸板包装标定方式,满足了瓦楞纸板包装生产的有效定位要求。     

Experiences with ATE Providing Testability of Microprocessor Boards

This paper describes studies of microprocessor board testing and specific experiences with boards containing the 8080 microprocessor being tested on GenRad's 1795 Logic Test System or high-speed 1796 Digital/Analog Test System. We have performed testing of microprocessor boards, based upon simulation using high-level functional models. The recommended test strategy is first to partition test activity into functional subsections of the board and then to increment the speed of test activity in stages. High-speed and synchronization capabilities are desirable features of the tester hardware. It is also desirable to have some simple testability features in the board design, specifically, control of the speed of board activity and control of microprocessor memory accesses. With such favorable conditions, effective testing of the microprocessor board is straightforward. When testability conditions are less than ideal, work-around techniques are required which tend to make test setup more difficult and/or tend to reduce test effectiveness.     

基于能量吸收法的U型纸质缓冲材料性能模拟分析

目的 研究采用U型瓦楞纸板进行缓冲包装设计的量化方法。方法 通过建立不同相关密度单层U型瓦楞纸板有限元模型,得到不同压缩速度下瓦楞纸板的应力-应变数据和单位体积吸收能量-应力数据,进行数据拟合得到相关密度方程和应变率方程。结果 随着相关密度的增加,瓦楞纸板的最大许用应力也在不断增加;从单位体积吸收能量-应力曲线上看,不同相关密度瓦楞纸板的最大许用应力包迹线呈线性关系;拟合的应变率方程和相关密度方程经验证可以方便高效地进行缓冲包装设计。结论 拟合的应变率方程和相关密度方程使用方便、快捷、高效,减少了查表法带来的误差,在实际生产中具有一定意义。     

纸蜂窝夹芯复合板材静态缓冲性能研究

目的为了新型纸蜂窝夹芯复合板材在运输包装中的推广应用,对新型泡状纸蜂窝夹芯复合板和纸蜂窝夹芯复合平板的缓冲性能和吸能特性进行研究。方法主要通过静态压缩实验,研究不同芯高的纸蜂窝结构类板材的应力-应变曲线、总能量吸收图、单位体积能量吸收图和缓冲系数-应变曲线,分析结构和芯高对板材静态压缩性能的影响。结果数据表明同种芯高的板材,纸蜂窝夹芯复合平板的应力峰值稍高;纸蜂窝夹芯复合平板的能量吸收、单位体积能量吸收最好;泡状纸蜂窝夹芯板由于泡结构的作用,缓冲性能大大增强。结论纸蜂窝夹芯复合平板的平压强度最好,而泡状纸蜂窝夹芯复合板的缓冲性能优于同等结构的蜂窝纸板,2种板材都有很好的应用前景。     

涂布两种施胶剂对抄制纸板物理性能的影响

目的对涂布氧化淀粉胶纸板、聚乙烯醇胶纸板和未涂布纸板的耐破强度、戳穿强度、挺度、防水防潮性等物理性能进行研究。方法实验选用表面施胶的方法来增强纸板的物理性能。通过抄制不同定量的化学机械浆和化学浆纸板,在纸板表面涂布相同体积的氧化淀粉胶和聚乙烯醇胶,测试纸板的物理性能。结果在相同温度、相对湿度条件下涂布施胶剂的纸板,其耐破强度、戳穿强度、挺度和防水防潮性要优于未涂布纸板;涂布聚乙烯醇的纸板其耐破强度、戳穿强度和防水防潮性要优于涂布氧化淀粉胶的纸板,涂布氧化淀粉胶的纸板挺度要优于涂布聚乙烯醇胶的纸板。结论涂布施胶剂后纸板的物理性能均有所提高,涂布聚乙烯醇胶的纸板强度较强,涂布氧化淀粉胶的纸板韧性较好。     

Design of a novel insulated construction material

The work described here covers the design and preliminary testing of a novel composite construction/insulation board, suitable for emergency shelters, and an initial study of appropriate manufacturing processes. The structure is a sandwich of closely packed recycled polystyrene cups between external grade medium density fibre (MDF) boards, bonded with foamed polyurethane. Load tests have shown that the assembly is comparable in strength and rigidity to conventional homogeneous construction boards, which meet current standards for domestic and light industrial flooring, but much lighter. Simple preliminary thermal tests, measuring the rate of cooling of a sealed box made from the board and containing hot water, indicate an insulation level comparable to that of a filled cavity wall. It is concluded that the board has industrial potential in general building as well as for emergency accommodation.     

Tube-Jack Testing for Irregular Masonry Walls: Regular Masonry Wall Testing

This paper presents the continued development of a novel non-destructive testing method termed tube-jack testing. The goal of the tube-jack system is to provide an enhanced and less destructive method than traditional flat-jack testing for determination of mechanical characteristics and local stress states in irregular masonry walls. Single tube-jack tests were performed, using previously developed rubber tube-jacks, in regular masonry walls of granite and cement-lime mortar. A traditional flat-jack test was also performed in the same masonry wall. Conclusions suggest that tube-jacks are successful in applying pressure to the masonry at low stress states.     

Preparation and Properties of Slag Wool Board using Modified Polyvinyl Alcohol as Binder

Slag wool boards were produced by using slag wool as the main raw material and adding modified polyvinyl alcohol (PVA) as the binder. The microstructure, thermal conductivity, compression strength, hydrophobicity, and other properties of the slag wool board were analyzed by using scanning electron microscopy, thermal conductivity tester, electronic universal testing machine, and other equipments. Also, the influence of different types and amount of binder on the properties of the slag wool board was studied. The results show that the addition of silica sol can improve the high temperature resistance of the slag wool board, and the addition of borax can improve the hydrophobic rate and compression strength of the slag wool board. Also, the concentration of PVA has obvious influence on the usage of silica sol and borax. In this study, we found that the optimal ratio of the binder should be 3 wt% addition of PVA, 20 wt% addition of silica sol, and 0.2 wt% of borax (relative to the amount of PVA), under the condition of satisfying the performance index of slag wool board and the convenience to spray the adhesive.     

扩孔率的测定及在检测中的应用

通过对扩孔试验原理的分析及扩孔率的测定,分析扩孔率在汽车专用薄板检测中与元素总量、薄板厚度、强度、伸长率和n^-值等的对应关系,从而阐明扩孔率可作为评价汽车专用薄板成形性的重要参数。     

Analysis and modelling of a production line in a corrugated box factory

This study deals with the development of a model for a production line in a corrugated box factory. The main feature of the study is to combine different problems in a single model. The problems considered in the model were; minimizing the waste resulting from cutting the paper rolls into carton boards for the products (cutting stock problem), utilizing the limited storage capacity to enable the corrugated board dry for a specified period of time (storage space problem), and utilizing the converting machines fully during a shift (machine loading problem). After a detailed analysis of the factory, a linear programming (LP) model was developed to obtain solutions to the above mentioned problems. A case example was selected based on the actual data from the factory records and solved using the LP model developed.     

热处理对玻璃纤维布/聚苯硫醚非织造布复合板材力学性能的影响

以玻璃纤维布和聚苯硫醚（PPS）非织造布分别作为增强体和树脂基体原料,采用热压成型法制备出玻璃纤维布/PPS非织造布复合板材,然后在烘箱中进行热处理。利用万能试验机（Instron）、XRD、偏光显微镜（PLM）和SEM等手段对玻璃纤维布/PPS非织造布复合板材的力学性能、结晶度、晶粒类型和尺寸及微观形貌等进行了测试和表征。结果表明：随着热处理温度和时间的提高,玻璃纤维布/PPS非织造布复合板材的弯曲强度、弯曲模量和缺口冲击强度得到明显提高。当热处理温度为220℃、热处理时间为2 h时,其力学性能最佳,其弯曲强度、弯曲模量和缺口冲击强度分别达到285.7 MPa、7.8 GPa和85.0 MPa。和未进行热处理的玻璃纤维布/PPS非织造布复合板材相比,分别提高了63.2%、469.0%和37.8%。微观形貌结果表明,玻璃纤维布/PPS非织造布复合板材界面粘结得到了明显改善。     

深拉延值的测定及其在薄板成形中的应用

通过对深拉延试验原理的分析及对深拉延值的测定，分析了深拉延值在汽车专用薄板检测中与rm值和薄板厚度开裂率之间的关系。从而阐明深拉延值可作为评价汽车专用薄板成形性的重要参数。     

多层UV形瓦楞纸板的准静态轴向压溃模型研究

目的 对多层UV型瓦楞纸板轴向压溃后的变形机理和抗压性能进行探究,以助于多层瓦楞纸箱和缓冲包装的设计。方法 采用理论分析和试验研究相结合的方式,对UV形多层瓦楞纸板轴向压溃后的平台应力进行理论建模和准静态试验研究。结果 在UV形瓦楞生产工艺的基础上,假设楞纸与相邻层之间的相互作用为面黏合;提出了一种新的折叠元件以及波纹芯的3种变形模式;此外,分别提出了五层瓦楞纸板和七层瓦楞纸板平台应力理论模型;多层瓦楞纸板平台应力的理论预测结果与试验结果吻合良好。结论 所提出的多层UV形瓦楞纸板理论模型是有效的,这将有助于波纹结构刚度设计和参数选择,以满足不同的强度要求。     

Influence of Wooden Board Strength Class on the Performance of Cross‐laminated Timber Plates Investigated by Means of Full‐field Deformation Measurements

Although cross‐laminated timber (CLT) plates are increasingly used in high‐performance building structures, a tailored composition of them or, at least, a performance‐based classification scheme is not available. Especially, the influence of the quality of the ‘raw’ material (wooden boards) on the load carrying capacity of CLT elements is hardly investigated yet. For this reason, within this work, bending tests on 24 CLT plates consisting of wooden boards from three different strength classes have been carried out. The global mechanical response as well as the formation of failure mechanisms were investigated, including a full‐field deformation measurement system, which allowed for a qualitatively as well as quantitatively identification of board failure modes. Interestingly, no influence of the board strength class on the elastic limit load of the CLT plates was observed, but the situation was different for the load displacement history beyond the elastic regime, where basically, two different global failure mechanisms could be distinguished. The obtained knowledge about the ‘post‐elastic’ behaviour of CLT plates may serve as a basis for the optimisation of CLT products and the development or improvement of design concepts, respectively. Moreover, the obtained large ‘post‐elastic’ capacity reserve of CLT consisting of high quality boards could lead to a better utilisation of the raw material.     

The strength of bagasse fibre-reinforced composites

The increasing board densities resulting from increased final platten pressure applied during production (or maximum moulding pressure) provides the reason for observations of similar increases in the Young's modulus and the tensile strength, when two phenol formaldehyde bonded boards which are reinforced with 80% and 90% by volume of bagasse fibres are examined. Scanning electron microscopy was carried out on the fracture zones to differentiate between the effects of varying formaldehyde content. However, even with differences in the sizes of the cavities formed at fracture and in the board densities, the observed modulus versus density and strength versus density curves follow exponential trends. By using the exponential trends, a single best linear tensile strength versus Young's modulus relationship is deduced for these varying fibre to matrix combinations.     

Zerstörungsarme Bestimmung der Steindruckfestigkeit von Bestandsmauerwerk aus Hochlochziegeln

Non‐destructive determination of the compressive strength in existing masonry made of vertically perforated bricks Urban consolidation and the conservation of listed buildings often require measures to determine the structural stability of the existing masonry. The key parameter for the static proof is the compressive strength of the masonry, which consists of the compressive strength of the bricks and the compressive strength of the mortar bed. So far, no testing methods have been developed that do not significantly interfere with the static load bearing capacity of masonry made of vertically perforated bricks and which make it possible to determine the compressive strength by analysing parts of the bricks. This article presents a non‐destructive test method to determine the compressive strength of vertically perforated bricks of existing masonry. This test method only uses small test specimens taken from parts of the bricks. As a result, the static load bearing capacity of the existing masonry is hardly affected. The results of these tests show that it is possible to establish a plausible correlation between the comprehensive strength of the brick and the compressive strength of the small test specimens. On this basis, a concept for a non‐destructive testing method which makes the determination of the compressive strength of vertically perforated bricks in existing buildings possible is presented.     

超高强钢热冲压工艺信息化管理系统搭建研究

目的 解决超高强钢热冲压工艺参数多且参数调整范围大,造成热冲压工艺设计难度大的问题。方法 以微软SQL Server数据库和ASP.Net Core为平台,通过Visual Studio C#集成开发环境进行B/S（浏览器/服务器）架构程序开发。结果 实现了集成普通板、补丁板、拼焊板、软硬分区板、不等厚板、其他板共6类板材,15种零件类型,以及相关的零件信息、产品要求、制造工艺、材料属性、供应商、产线、设备等7类数据信息的超高强钢热冲压工艺信息化管理系统软件。结论 该系统实现了超高强钢热冲压工艺数据录入与存储,多种数据信息相互关联、按需检索与联合查询以及用户管理和维护功能,为国内超高强钢热冲压工艺技术研究与产品开发提供系统架构参考。     

Hygromorphic response dynamics of oak: towards accelerated material characterization

When a wood board is exposed to a change in relative humidity on only one of its surfaces, e.g. in case of flooring or a panel painting, the resulting asymmetric moisture content profile induces differential expansion over the thickness. Consequently a bending moment causes the board to curve. A theory is presented to describe the bending of a wood board due to a step change in relative humidity. The board is assumed to be homogeneous, isotropic, and linearly elastic. Moisture transport is presumed to obey the diffusion equation with constant coefficients, such that moisture transport can be directly related to the bending of the board. It is shown that the transient deflective behavior provides the diffusion coefficient and the final length change yields the linear hygroscopic expansion coefficient. Derived diffusion coefficients are in good agreement with values in literature. Furthermore, a scaling law for the deflection of the board is proposed, which is seen to be followed qualitatively but not quantitatively by experiments. Finally, by assuming the deflection of the board to be the response of a linear system, the deflective frequency response of the board can be predicted from its step response. The results allow upscaling of deflection and expansion, such that behavior of thick boards can be determined from an experiment using a thin board.     

Prediction of bending strength of long corrugated boxes

Long corrugated boxes were supported at both ends and bent by a concentrated force applied at the middle. Boxes with different lengths, cross‐sectional shapes, flute directions and board strengths were tested, using a standard compression tester with a fixed platen in accordance with ASTM D‐642. An equation was developed to relate compression strength to the various properties of the box. The correlation coefficient R² for the fit to actual data was about 0.4. Boxes having the flutes run around the box had a 20% higher compression strength than with horizontal flutes. The most significant factor was found to be the board edge crush strength. The results suggest that failure of boxes in bending is due to localized crushing at the point of application of the load, rather than whole‐box collapse. Copyright © 2001 John Wiley & Sons, Ltd.     

Manufacture of three-layer wood–porcelain stone composite board reinforced with bamboo fiber

The objective of this study was to improve bending strength properties of three-layer wood–porcelain stone composite board. The focus of this study was on the effects of orientations and weight ratios of bamboo fiber in face layer on physical and mechanical properties of the board. Three types of board with different orientation of bamboo fibers in the face layer were manufactured: one in which the fibers were oriented at random orientation (R board), another in which the fibers were oriented at unidirectional orientation (U board), and a third in which the fibers were oriented at cross orientation (C board). The physical and mechanical properties of the boards were evaluated based on the Japanese Industrial Standard for Particleboards. The main results obtained were as follows: Bending strength properties of the board were strongly affected by both orientation and weight ratio of bamboo fibers. Perpendicular specimen of C board has larger bending strength properties than U board and the value become larger with increased weight ratio of bamboo fibers. Internal bond strength value decreased with increasing weight ratio of bamboo fibers. The effect of orientation and weight ratios of bamboo fiber on thickness swelling of the board was not significant.