Potential Use of Foamed Mortar (FM) for Thermal Upgrading of Chinese Traditional Hui-Style Residences

The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m²·K/W, which is even higher than 0.67 m²·K/W for the code required in the hot summer/cold winter climate zone.     

Spatial variation in cervical cancer screening participation and outcomes among Indigenous and non‐Indigenous Australians in Queensland

Indigenous women continue to experience a disproportionately higher burden of cervical cancer than non‐Indigenous women in Australia. The National Indigenous Cervical Screening Project used probabilistic record linkage to combine population‐based administrative databases and identify Indigenous women on Pap Smear Registers. This study aimed to quantify the spatial variation by local government areas (LGAs) for Indigenous and non‐Indigenous women in Queensland in cervical screening participation rates and related outcomes. Empirical Bayes local geostatistical smoothing was performed to reduce the likelihood of spurious variation between small areas. The cohort included 1,091,260 women (2 per cent Indigenous) aged 20 to 69 with 2,393,708 Pap smears between 2006 and 2011. Indigenous women had smoothed LGA‐specific 5‐year participation rates (interquartile range (IQR) 38.9–53.3 per 100 eligible women) consistently lower than non‐Indigenous women (IQR 80.7–85.3). The non‐overlapping confidence intervals of these rates suggest that the Indigenous differential was significant. Compared with Indigenous women, non‐Indigenous women had consistently lower and more stable prevalence rates of histologically confirmed high grade abnormalities (IQR 8.0–10.1 versus 15.0–21.3 per 1,000 screened women). Although the LGA‐specific rates also suggest that a higher proportion of non‐Indigenous women were followed‐up within two months of an abnormal screening result, the wide confidence intervals for these estimates limit our ability to draw definitive conclusions about spatial patterns for this outcome. These findings highlight the importance of continued monitoring and ongoing efforts to identify drivers of these patterns and develop effective strategies to improve participation and potentially reduce the cervical cancer burden among Indigenous women.     

Stone Age fishhooks – how were they dimensioned? Morphology,strength test,and breakage pattern of Neolithic bone fishhooks from Ajvide,Gotland, Sweden

The late Stone Age Pitted Ware site at Ajvide, Gotland, in the Baltic Sea, Sweden, has revealed a large deposit of fishbone and approximately 400 bone fishhooks, complete and incomplete. Cod (Gadus morhua), which is one of the most abundant fish species in the bone assemblage, was probably caught with hook and line fishing. To investigate the fishhooks' field of application, a morphological and morphometric study was performed on 384 available hooks. Two sets of replicas made of four selected original fishhooks were submitted to a strength test. A breakage study of the incomplete hooks in comparison with the strength-tested hooks was carried out in order to distinguish fresh breaks from dry breaks. It seems that a certain morphology for fishhooks was preferred at Ajvide, indicating they were produced by skilled craftsmen for special usage. The strength test showed that the hooks had a weight bearing capacity more than the average size of cod caught at Ajvide. Using results of these tests, we predicted that the mean breaking strength of 46 intact Ajvide hooks was 96.6 ± 26.1 (s.d.) Newtons (equivalent to 9.85 ± 2.7 kg). The design of fishhooks changed somewhat over time, being slightly larger in the oldest layers of the site. The breakage patterns of the hooks show that the bow was the most common area of breakage. The design and weight bearing capacity of the hooks point to a specialized cod fishery from boats in deep water.     

The use of multiple discriminant analysis in classifying prehistoric phytolith assemblages recovered from cooking residues

In the investigation of the dispersal of maize (Zea mays ssp. mays) from south-central Mexico to the northern and southern limits of agriculture in the Western Hemisphere archaeologists and paleoethnobotanists are increasingly turning to the microbotanical record. Recent analysis of phytolith assemblages from charred cooking residues on pottery sherds in central New York recovered using 209 rondel phytolith variables has identified maize as early as 2270 ± 35 B.P. In this article we use discriminant analysis to re-classify these rondel phytolith assemblages resulting in only seven variables. The results are consistent with those achieved earlier using many more variables and a less formal statistical approach in terms of classification and in similarity of the original and reduced data matrix as seen by the Mantel test and cluster analyses.     

西部十二省、自治区、直辖市旅游竞争力的组合评价

对一个地区的旅游竞争力进行评价有助于客观地了解该地区旅游业的发展状况,而科学合理的评价依赖于评价指标和评价方法的选择。本文提出了合理选择指标的原则,并在所构建的旅游竞争力评价指标体系中引入了＂软＂指标。由于单一评价模型的评价结果各不相同,本文引入组合评价模型对西部十二省、自治区、直辖市的旅游竞争力进行评价,然后采用斯皮尔曼等级相关系数对组合评价结果进行检验,结果显示本文采用的组合评价方法与其它评价方法的一致性最高,说明该方法能比较客观综合地反映旅游竞争力状况。最后,通过聚类分析,进一步验证了本文方法的有效性。     

基于价值转移方法的我国游憩活动价值评价

鉴于目前我国在构建价值转移模型中存在的限制因素,本文采用基于Meta分析的价值转移方法并尝试利用国外游憩活动价值评价的实证研究结果,构建基于Meta分析的国际间价值函数转移模型,估算了我国10种游憩活动的日平均消费者剩余.通过将价值转移模型估算的游憩活动价值“转移值”与国内97个游憩价值评价的“真实值”做比较,对价值转移模型的有效性和可靠性进行统计检验,平均转移误差为18.74％.最后,总结了提高我国Meta回归价值转移模型的具体、可操作性方法及途径.     

A COMPARATIVE STUDY OF STRENGTHENING AND RETROFITTING MEASURES FOR UNREINFORCED BRICK MASONRY MODEL UNDER CYCLIC TESTING

An experimental study on half-scale brick-masonry models with different strengthening and retrofitting measures has been studied under cyclic loading in a quasi-static test facility. The strengthening measures undertaken for the studies axe the horizontal bond beam at the lintel and sill level with a combination of vertical reinforcement at corners and openings. The retrofitting measures studied are grouting with epoxy-sand-mortar and cement-grout-injection with welded wire mesh in the cracked region. The tests reveal that the horizontal bond beam at lintel level with vertical reinforcement is effective in reducing the cracking above the lintel level. The insertion of an additional sill-band signi-ficantly reduces the cracking in walls. The epoxy-sand-mortar techniques for retrofitting of cracked regions prove to be effective enough to restore the initial strength, stiffness and deformation capacity. Although specimen retrofitted with cement-grout-injection with welded wire mesh is effective to regain the ultimate strength yet the brittle failure is observed as the specimen is stressed beyond the elastic limit.     

旅游业与我国经济增长关系的实证分析

旅游业与国民经济增长之间的关系一直是有关学者研究的对象,这也导致了对旅游业地位的不同认识。本文利用历史数据对改革开放以来中国居民旅游消费支出与经济增长之间的关系作出判断,认为我国旅游业与经济增长之间并不存在稳定的因果关系。文章对产生这种现象的原因进行了分析,并提出了相关政策建议。     

声频应力波法检测土遗址加固用玻璃纤维锚杆锚固质量初探

土遗址锚杆锚固质量一直是土遗址加固工程中关注的重点问题。目前,土遗址领域均采用具有破坏性的拉拔试验对其进行检测。基于土遗址的文物属性,本研究尝试利用无损检测技术评价土遗址加固用玻璃纤维锚杆的锚固质量。通过锚杆无损检测仪与拉拔仪分别对甘肃省红沙堡遗址与永泰城址加固工程中的玻璃纤维锚杆锚固系统进行检测。比较实际测量杆长与仪器测量杆长结果,得出杆长指标可以判断无损检测仪所测结果的真实性。无损检测仪得出的检测波形衰减规律显著,对比相应锚杆的拉拔试验的评价结果,证实了声频应力波法在土遗址玻璃纤维锚杆锚固系统无损检测中的适用性。本研究结果将为评价土遗址加固用玻璃纤维锚杆锚固质量提供可靠的依据。     

大雁塔盐害及劣化模拟试验研究

易溶盐富集是陕西西安大雁塔砖体表面风化、结构破坏、强度衰减的主要原因。为分析盐害对大雁塔砖体结构、强度的影响机理,采用以饱和硫酸钠溶液为介质,对大雁塔砖体进行易溶盐结晶循环模拟劣化试验。在Na₂SO₄反复结晶、溶解过程中,测定试样的质量、波速及单轴抗压强度等指标,分析其变化规律。结果表明,在盐害作用下,试验砖体表现出与塔体表面类似的风化破坏现象;Na₂SO₄晶体在试样孔隙内不断发育,晶体挤压效应导致孔隙率增大,内部结构破损;质量、波速、单轴抗压强度随循环的次数呈先增加后减小的变化规律。砖体对盐害耐受力约为砖体质量的0.5%。