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11.
THEOPHILUS O. ODEKUNLE 《Geographical Research》2010,48(3):314-326
This study assessed the influence of the Inter-Tropical Discontinuity (ITD) on inter-annual rainfall characteristics in Nigeria between 1970 and 2000. This involved determining the strength and direction of the relationships between the total annual rainfalls in the extreme southern and northern parts of the country and the total annual rainfalls during the period of the Little Dry Season in southwestern Nigeria, and the surface locations of the ITD over Nigeria and some other factors that may impact ITD characteristics (such as the pressure differences between Azores, Libyan and St. Helena anticyclones and the sea surface temperature of the Gulf of Guinea). Results indicate that although the surface location of the ITD significantly accounts for rainfall inter-annual variability in Nigeria, it does so in the northern part of the country only. Pressure differences between the various anticyclones were observed to be another significant factor influencing inter-annual rainfall variability in the north. However, the influence of the sea surface temperature of the Gulf of Guinea on the rainfall characteristics in the northern region is ill-defined. It was also noted that the only factor influencing inter-annual variability in the Little Dry Season rainfall in the southwest and the total annual rainfalls in the south is the sea surface temperature of the Gulf of Guinea. The results obtained indicate that the total annual rainfalls in the north have significant positive relationships with the surface location of the ITD but significant negative relationships with the pressure differences between the Azores, Libyan and St. Helena anticyclones. The Little Dry Season rainfalls and total annual rainfalls in the south have significant positive relationships with the sea surface temperature of the Gulf of Guinea. 相似文献
12.
战后日本女性文学伴随着日本社会体制的剧烈变化,以及民主主义思潮的冲击,女权主义的鼓噪和经济高速增长下衍生的都市化情怀的洗礼,呈现出与以往全然不同的盛况,使同时代的日本女性文学基于富饶的时代土壤,开出绚丽的花朵。 相似文献
13.
The growth of collaborative approaches to governance has resulted in increasingly complex policy and management landscapes, where actors are presented with ever‐increasing numbers of decision‐making venues they can participate in and actors they can collaborate with. Given that actors face constraints on their capacity to manage actor and venue relationships in such polycentric governance systems, we assume the marginal benefit of yet another relationship should begin to diminish at some level of engagement. Furthermore, we hypothesize that such capacity limitations are not static, but decrease as actors learn, develop skills, and formulate strategies for how to navigate complex polycentric systems more effectively. Drawing on the Ecology of Games framework, this article investigates two Swedish collaborative governance initiatives where a multitude of actors came together to address a range of different, but interrelated, policy issues and management tasks. The empirical findings suggest that actors’ capacities to successfully navigate polycentric governance arrangements increase as they gain experience and develop their networking skills. Our findings imply there is a need to balance increased complexity in polycentric systems with increased capacity, otherwise the overall effect of an ever‐increasing number of venues and actors could be collaborative fatigue and decreased abilities to address diverse governance challenges. 相似文献
14.
此研究是以石材和土壤所构成的考古遗址为主要研究对象。在确定石材和土壤的渗透性下,通过数字体积相关法(DVC)和数字图像相关法(DIC)对干湿劣化的环境条件进行定量的评估,并提出控制这种劣化发生的环境调整方法。 为了收集基本数据,通过DIC及X射线成像技术分析从湿润到干燥的过程中丰浦硅砂的位移量实验,并在实验中,使用DIC计算样品在收缩应力下的变形分布。此外,本次实验以铁粉作为示踪剂添加至样品中,并以铁粉作为参考点计算丰浦硅砂特定范围的移动量,借此评估铁粉作为示踪剂的适用性及精确性。结果表明,通过拍摄干燥前后样品的X射线图像,并用DIC进行分析可以计算出干燥前后的变形分布。在样品中添加示踪剂也被发现有助于分析样品局部区域的移动方向及移动量。因此通过此基本数据的检验,相信将来通过X射线计算机断层扫描(X-CT)及数字体积相关法(DVC)的应用,可以用来阐明反复干湿风化的劣化机制。 相似文献
15.
耿兴岩 《文物保护与考古科学》2023,35(4):150-158
本文对纸质文献的干式清洁方法进行了系统梳理,介绍了十种常用的方法,并说明其工具、材料及操作过程,对存在的问题和优缺点做出简要评价。除此之外,还介绍了三种较前沿的方法,并对其原理和研究现状进行了总结及评价。 相似文献
16.
考古发掘中的地层剖面在历史研究中占有重要地位。在北京琉璃河遗址进行的地层剖面薄层标本揭取,使用了日本奈良化财研究所开发的新材科和技术,经刷树脂、贴纱布、揭取、水洗、表面处理等步骤完成。这次揭取工作的成功,为更精确的记录、保存、研究及展示考古发掘资科提供了新方法,在考古发掘工作中使用前最广泛。 相似文献
17.
Daniel W. Harrington Kathi Wilson Susan J. Elliott Ann E. Clarke 《The Canadian geographer》2013,57(4):431-440
18.
Angela Coyle 《对极》2010,42(2):289-309
Abstract: The relocation of thousands of call centre and back office jobs from the UK to subcontractors in India in the early 2000s led to extensive speculation that the “globalisation” and “jobs flight” of service work was underway. Yet as this article illustrates some call centre customer services do not easily transfer to different local, social and cultural contexts. Call centre operations are embedded in local social relations and taken for granted skills that are difficult to reproduce outside of the locality which has produced them. Nevertheless the spatial dispersal of work can be as much a political process as it is an economic one. This article, which follows the journey of 1000 call centre jobs from the UK to India, illuminates how subcontracting service work “offshore” can facilitate a transformation of the employment relation and an escape from a difficult to discipline labour force. 相似文献
19.
在纪念敦煌藏经洞发现100年之际 ,甘肃人民出版社对甘肃境内收藏的敦煌汉文文献进行普查、鉴定、整理、拍摄 ,结集出版了《甘肃藏敦煌文献》一书。本文对书中文献来源及特点 ,与混其中的疑伪品未收入此书的赝品作了述论。 相似文献
20.
Francesco Boschin 《International Journal of Osteoarchaeology》2020,30(1):3-12
This paper poses a question on the interpretation of caprine “kill‐off patterns” in some prehistoric sites of the Caput Adriae (northern Adriatic region, Mediterranean area). In particular, caprine kill‐off data from layers 2 (Late Neolithic‐Copper Age) and 2a (Middle Neolithic) of Grotta dell'Edera (Trieste Karst, north‐eastern Italy) are presented here and compared with those from two neighbouring sites. Distribution of age classes of domestic animals (in particular Caprinae) is generally discussed in terms of exploitation strategies adopted by past communities to obtain different products (e.g., milk, meat, and wool). Nevertheless, emphasis is rarely given to the possible meaning of the presence of foetal individuals and to their relation with neonatal ones. In this sense, it needs to be considered that causes of abortion (e.g., infections or ewe malnutrition) often can also lead to lamb mortality. The presence of a high proportion of neonatal (0–2 months old) and foetal sheep/goat individuals in the sites analysed raises an issue about the possible meaning of the mortality profiles: exploitation of dairy products or just premature death of ill individuals? This issue is important not only to better interpret subsistence strategies of past human communities but also to explore animal disease through time. 相似文献