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1.
    
Fijian bodies have become a valuable commodity in the economy of war. Remittances from workers overseas are Fiji's largest income – exceeding that of tourism and sugar export. This essay examines historical and contemporary representations of the black male body that perpetuate the exploitation of Fijians by inscribing the Fijian male body as warrior, criminal and protector. Taking a multidisciplinary approach informed by sociology, cultural theory, Pacific studies, visual culture, feminist and post-colonial theory, my practice is the vehicle through which I address issues of neocolonial commodification of Fijian bodies. Through an analysis of my own staged photographs and vernacular images taken by Fijians working for private security military companies and British and US armies, I hope to challenge audiences to consider their own perceptions of Fijian agency and subjectivity. By theorising the politicisation of the black body and interrogating colonial representations of blackness, I argue that we can begin to create links between the historical and contemporary exploitation of Fijians and that at the essence of both is an underlying racial hierarchy and economic requirement for cheap and, arguably, expendable labour.  相似文献   
2.
    
Water stress and fire disturbance can directly impact stand structure, biomass and composition by causing mortality and influencing competitive interactions among trees. However, open eucalypt forests of southwest Australia are highly resilient to fire and drought and may respond differently to increased fire frequency and aridity than forests dominated by non-eucalypt species. We measured the variation in stem density, basal area, stand biomass, sapwood area, leaf area and litterfall across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands along an aridity gradient in southwest Australia that had variable fire histories. Fire frequency was defined as the total number of fires over a ∼30-year period and aridity as the ratio of potential evapotranspiration to annual precipitation. Total stand biomass and sapwood area were predicted from diameter at breast height of individual jarrah and marri trees using allometric equations. Leaf area was estimated using digital cover photography. More arid and frequently burnt stands had higher stem density, especially of smaller trees, which were mainly jarrah. Overall, both standing biomass and leaf area decreased at more arid sites, while sapwood area was largely unaffected by aridity, suggesting that these stands respond to increased water limitation by decreasing their leaf area relative to their sapwood area. Biomass of marri was reduced at more arid and, to a lesser extent, at more frequently burnt stands. However, total stand biomass (jarrah and marri) and leaf area index did not vary with fire frequency, suggesting that less marri biomass (due to slower growth rates, higher mortality or less recruitment) was compensated by an increase in the density of jarrah trees (regeneration). We conclude that increased fire and drought shift tree species composition towards more fire-resistant species and result in denser stands of smaller trees. In contrast, total stand biomass declines with increasing aridity, but has no association with fire frequency.  相似文献   
3.
Using soft X-ray photography, two-dimensional observations were made of the water distribution within the green stem ofCryptomeria japonica D. Don. Variations in the distribution pattern of the wet area in the horizontal plane of the lower stem were described. The distribution patterns showed extreme variation among individual trees, with broad wet-area distribution types appearing, namely, the regularly distributed wet area and the irregularly distributed wet area. We defined five basic types of wet-area distribution patterns on the basis of their regularity or irregularity. It was concluded that the between-tree variation in the wet-area distribution causes the between-tree variation in the mean moisture content of the heartwood. The distribution patterns of the wet area were similar for individual trees within each plus-tree clone.Part of this paper was presented at 46th annual meeting of the Japan Wood Research Society at Kumamoto, April 1996  相似文献   
4.
Aerial photography provides a historical vehicle for determining long-term urban landscape change and, with concurrent daily streamflow and precipitation records, allows the historical relationship of anthropogenic impervious surfaces and streamflow to be explored. Anthropogenic impervious surface area in the upper Accotink Creek subwatershed (near Annandala, Virginia, USA) was mapped from six dates of rectified historical aerial photography ranging from 1949 to 1994. Results show that anthropogenic impervious surface area has grown from approximately 3% in 1949 to 33% in 1994. Coincident to this period, analysis of historical mean daily streamflow shows a statistically significant increase in the streamflow discharge response (per meter of precipitation) associated with normal and extreme daily precipitation levels. Significant changes were also observed in the frequency of daily streamflow discharge at given volumes above and below the historical daily mean. Simultaneously, the historical magnitude, frequency and pattern of precipitation values 0 mm, 6.0 mm and 35.0 mm show either no statistically significant change or influence on streamflow. Historical changes in streamflow in this basin appear to be related to increases in anthropogenic impervious surface cover. Historical aerial photography is a viable tool for revealing long-term landscape and ecosystem relationships, and allows landscape investigations to extend beyond the temporal and spatial constraints of historical satellite remote sensing data.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
5.
    
The edges of the Ethiopian Plateau are affected by frequent landslides predisposed by pronounced seasonality in precipitation, thick weathering mantle of volcanic material, and rough relief. We analyzed the three‐dimensional dynamics of three large landslides in Dessie using digital elevation models and ortho‐images derived from a time‐series of aerial photographs reaching back to 1936. Furthermore, we utilized repeated photography based on terrestrial photographs from the 1930s and 1940s to analyze landscape changes. It was revealed that the large sliding zone (25.4 ha) in lacustrine sediments at Kerra locality existed approximately in the present extent already before 1936. The volume of depleted material of the 1986–1994 rock slide at Doro Mezleya locality was assessed as 1.82 106 m3 with mean vertical thickness of 48 m. Additionally, we described the nowadays inactive Hot Spring landslide (12.9 ha). We documented a large scale reforestation of the area carried out as a remediation measure and rapid changes in land cover and settlement structure. We conclude that two out of three studied large landslides existed before 1936 and thus are not induced by the increased human pressure on the landscape of the last decades. Additionally, we provide an overview about collections of historical aerial photographs of Ethiopia, and we discuss their potential and drawbacks for mass wasting studies.  相似文献   
6.
本文提出了动态摄影的概念,并研制出其实用装置,用来拍摄插秧机分插机构秧爪运动轨迹照片,对研究、试制及鉴定插秧机性能起了重要作用。  相似文献   
7.
Catfish fillets with yellow coloration have become a prevalent problem for the catfish industry. This problem is due to the unacceptability in the market because the shift in fillet color is considered of lower quality by the consumers. To help the catfish industry better understand the yellow coloration of catfish fillet, a digital photography measurement method was developed to evaluate the yellowness. Sixty catfish fillets with a range of degrees of visible yellowness were taken directly from the processing line. The fillets were photographed in a light box with a digital camera. The photos were calibrated with the X-Rite ColorChecker standardized color target. CIELAB readings of the fillet photos were recorded, and the b* value was used to indicate the yellowness of catfish fillets. The xanthophyll levels of fillets were analyzed with high performance liquid chromatography. The actual xanthophyll level in catfish fillet was calculated as the sum of lutein, zeaxanthin, and alloxanthin. A linear correlation was found between the LAB b* values and xanthophyll levels of the 60 catfish fillets.  相似文献   
8.
报告了花生幼苗(苗龄为6d)中多胺氧化酶的组织化学定位,并就该酶定位研究中的摄影问题提出了几点看法  相似文献   
9.
摆动分离筛薯土分离机理分析与参数优化试验   总被引:5,自引:0,他引:5       下载免费PDF全文
针对摆动分离筛薯土分离机理不明确,作业参数匹配不合理导致明薯率与马铃薯破皮率矛盾突出等问题,利用高速摄像机实时拍摄不同曲柄转速、筛面倾角和机器前进速度时摆动分离筛上薯土混合物的分布状态,统计并分析薯土混合物分布高度的变化规律,揭示薯土分离机理,并获得影响分离筛性能主要因素的取值范围。以明薯率和破皮率为评价指标,采用Box-Behnken响应面试验方法进行试验,建立各指标与因素间的回归数学模型,对影响摆动分离筛性能的结构与工作参数进行优化。结果表明,各因素对明薯率、破皮率影响由大到小为曲柄转速、筛面倾角、机器前进速度。摆动分离筛优化参数组合为:曲柄转速230 r/min,筛面倾角21.1°,机器前进速度2.03 km/h,优化后明薯率和破皮率分别为98.94%和0.21%,明薯率较优化前提高1.68个百分点,破皮率较优化前降低9.6个百分点,参数优化试验结果满足国家标准要求。  相似文献   
10.
为解决脱穗之后的玉米种粒三维特征的获取和分析这个重要而又困难的问题,该研究基于机器视觉技术开发了一种融合三维特征的玉米种粒考种装置。装置通过2块相互垂直的标定板来保留倾斜影像中的空间信息和标定数据,并据此计算三维数据。基于装置的标定数据,用图像处理的方法获取玉米种粒的长度、宽度和厚度数值。通过透视变换,从倾斜摄影图像分别得到水平正摄和垂直正摄的图像;玉米种粒轮廓的长轴和短轴以旋转盘的直径为参考进行计算;玉米种粒的厚度以垂直方向棋盘格标定数据为参考进行计算。按照10帧/s的帧率和1 280×720的图像分辨率启动图像记录系统。选取180粒不同品种的玉米种粒进行试验。种粒长轴、短轴和厚度测量的均方根误差分别为1.86、1.28和0.741 mm;决定系数分别是0.849 6、0.869 3和0.846 2。使用该装置并配合相应的方法能较为准确的一次性测量玉米种粒的三维参数,该研究可为玉米种粒的精细化考种提供参考。  相似文献   
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