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1.
基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定. 相似文献
2.
冯儒梅 《中小企业管理与科技》2021,(9)
随着我国电网逐渐向智能电网迈进,信息技术在电能传输、转换、分配、调度等方面的应用,使电力企业可以进行结构调整,提高电力系统管理水平。据统计,2011年,我国电力信息化投资达220亿元,2012-2015年,电力工程建设稳步推进。为了促进电力企业全面开展项目成本核算和有效控制,提高电力工程项目的效益,确定了典型方案设计模块,通过定额规则库与典型方案设计相匹配的方法,解决了安装过程中定额第一版遗留的一些问题,并通过设计选型等措施加强了成本控制。 相似文献
4.
Keri Vacanti Brondo 《Journal of Sustainable Tourism》2019,27(4):590-607
AbstractThrough a case study of conservation voluntourism this article brings together critical political ecology, multispecies ethnography, and studies of humanitarian tourism to advance a political ecology of multispecies conservation voluntourism. The article presents multispecies conservation voluntourism as a field that produces and is produced by an “affect economy”, or an economy based on the exchange or trade in the relational. Since the mid-1990s, life on Utila, Honduras, a popular discount backpacker scuba destination located along the Mesoamerican Barrier Reef, has been deeply transformed by the growth of dive tourism, the ecological destruction it has produced, and now the conservation voluntourism industry emerging in its wake. Seventy percent of Utila is comprised of mangroves and associated wetlands, home to several endangered and endemic species. Using examples of whale shark tourism, lionfish hunts, and iguana tracking, this article shows how conservation organizations operate as affect generators, enabling the privilege of engaging in multispecies encounters. Engaging in multispecies conservation voluntourism produces value in the form of cultural capital which is then exchanged for material outcomes by volunteers in the global economy; at the same time, this form of voluntourism obscures local relationships to nature and alters multispecies assemblages from past configurations. 相似文献
5.
Hayley Stainton 《旅游业当前问题》2018,21(9):1075-1084
The use of the Internet is becoming increasingly integral to the day-to-day operations of society, facilitating an interconnected and globalised world, where geographic barriers are no longer a defining criteria for communication. This opens the researcher up to a realm of research opportunities, which to-date have been under-exploited. This paper contributes to the wider body of literature addressing the concept of Online research, demonstrating in practice how it can be utilised in the context of interpretative phenomenological analysis. It is argued that netnography is akin to interpretative phenomenological analysis (IPA) in that it accounts for an individual’s personal perception or account of an event or state, as opposed to attempting to produce an objective record. This paper outlines how blog analysis can be utilised in the context of IPA, demonstrating how this worked in practice during the initial exploratory research phase of the teaching English as a foreign language tourism phenomenon. 相似文献
6.
ABSTRACTThis article recounts three stories from TEFI’s walking workshop in Nepal: the construction of a road through what was once a trekking path; a dance-floor encounter at a Himalayan party; and the arrival of one participant, fatigued by jet lag and disoriented by the new surroundings. These stories of confusion, discomfort and fear are linked by one common theme: the potential of uncertainty to foster deep reflection and nuanced conclusions. The premise that uncertainty is to be valued and even cultivated has been explored in educational theory, spiritual traditions, and research on transformative learning. These sources affirm the role of uncertainty in the process of knowledge creation. However, accepting this role can be challenging for educators because it requires they assume a new identity, one which they may perceive as being at odds with their status as “teacher” the identity of learner. One way for the educator to address this challenge may be through recounting their own stories of uncertainty. Stories of being immersed in unfamiliar situations that challenge, confuse and even frighten – stories, in other words of being a tourist – can foster reflection on an intellectual, emotional and spiritual level, engaging the “whole” person, and thus initiating the educator/learner’s transformative journey. 相似文献
7.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。 相似文献
8.
The deterioration of attractions, landmarks, artefacts and destinations is a critical issue facing tourism across the world. The closure of tourism sites and attractions is increasingly more common due to the difficulty and expense of managing preservation with onsite tourism engagement. However, the closure or destruction of tourism sites presents challenges for tourism development. The inability to foster meaningful visitor engagement at sites has implications for the local communities. This paper aims to explore the efficacy of creating tourism experiences in destinations and sites that have succumbed to over-tourism, resultant deterioration and even, destruction. To achieve this objective, the paper introduces the concept of second chance tourism and the role of innovative preservation methods such as virtual and mixed reality. Based on the proposed framework, the collation of data will provide indications on site preservation and impact mitigation via a second chance to reduce pressure on inherently fragile destinations. 相似文献
9.
ABSTRACT Tourism and tourism development have the potential to make a positive impact on a region’s economic development and sustainability. In this sense, the central Karoo has a great deal to offer heritage tourists. As there are numerous battlefield sites associated with the South African War (1899–1902) (previously the Anglo-Boer War) the central Karoo offers a unique development opportunity to demarcate a designated battlefield route dedicated to the war. This study investigated the potential for the development of the proposed route by involving potential stakeholders (specifically product owners and government officials) on the route. The study was qualitative, and 33 interviews were conducted. Thematic content analysis was used to analyse the data. The main findings indicate a need for the development of the route and the establishment of a South African War Battlefields Route Destination Marketing Organisation (DMO). 相似文献
10.
ABSTRACTIn this paper, Weaver’s six-stage indigenous tourism model is applied to the Lacandon Maya (Hach Winik) of Chiapas, Mexico. Based on a comprehensive review of the anthropological and historical literature on this indigenous group, combined with longitudinal ethnographic and collaborative research performed with tourism entrepreneurs, the Lacandon tourism experience is assessed from the pre-European period until present. By analysing a case study of indigenous tourism in Mexico, a developing country in another geographical region and with a different colonial past, this work supplements Weavers’ perspective. The results show that the fourth and fifth stages of Weaver’s model coincide in this case study, while the sixth stage is still incomplete. Although the Lacandon case has its peculiarities and bearing in mind that several different factors should be considered in the Latin American context, the model proves to be an interesting tool for indigenous tourism analysis in developing countries. 相似文献