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1.
本文试图通过对乔家、曹家、王家、渠家、常家五大“晋商大院”这一旅游品牌的品评,引发人们对晋商兴衰问题的思考,并且促进人们对晋商大院游的浓郁兴趣。  相似文献   
2.
在船舶建造过程中焊接工作量约占全部的30%~40%,焊接是保证质量的重中之重。焊接质量出问题,就可能造成严重的后果。我厂沿江堤而建,空气中湿度大,工作条件差。密集性气孔很严重。所以,在这种情况下,对我厂焊接质量控制提出更高的要求。  相似文献   
3.
基于CVM方法对福州国家森林公园的游憩价值进行评价,调查结果得出:2015年福州国家森林公园的游憩价值为2.164亿元。游客对公园的满意度和旅游次数与游客的支付意愿呈显著正相关(p0.05),游客的家庭人口数(p0.01)、月收入(p0.01)和职称(p0.05)与游客的WTP值呈显著正相关。基于研究,景区应在生态环境、服务设施和质量上进一步挖掘公园潜在的游憩价值,并在游客森林游憩过程中,普及生态环境知识和宣传教育,提高游客的生态保护意识。  相似文献   
4.
深度学习模型中的特征金字塔网络(Feature Pyramid Network,FPN)常被用作合成孔径雷达(Synthetic Aperture Radar,SAR)图像中多目标船舶的检测。针对复杂场景下多目标船舶检测问题,提出了一种基于改进锚点框的FPN模型。首先将特征金字塔模型嵌入传统的RPN(Region Proposal Network)并映射成新的特征空间用于目标检测,然后利用基于形状相似度距离(Shape Similar Distance,SSD)度量的Kmeans聚类算法优化FPN的初始锚点框,并使用SAR船舶数据集测试。实验结果表明,所提算法目标检测精确率达到98.62%,在复杂场景下与YOLO、Faster RCNN、FPN based on VGG/ResNet等模型进行对比,模型准确率提高,整体性能更好。  相似文献   
5.
A combined travel cost – contingent behaviour survey of residents and tourists in Catalonia is conducted on-site to examine the effects on beach recreational demand of developing an offshore wind farm (OWF) project. The survey considers four potential OWF scenarios with different degrees of visual impact. We allow for heterogeneity in trip preferences among individuals and control for on-site sampling through the use of a random parameters negative binomial (RPNB) model and a Multivariate Poisson log-normal (MPLN) model, respectively. The welfare measures derived from the RPNB model relate to the current beach users only, whereas those from the MPLN model refer to the general population of residents and tourists in Catalonia. The results show the importance of the specific place of location of the OWF project and how the installation of wind turbines would significantly decrease the demand for trips, depending on their degree of visual impacts, leading to a substantial welfare loss. However, the results also show that the project mainly would cause a displacement of trips to other beaches within Catalonia rather than outside Catalonia and that the welfare per trip measures generated by the RPNB and MPLN models substantially differ. Policy implications of these findings are discussed.  相似文献   
6.
吴东鹏  袁野  张正利  刘西潼  王健 《价值工程》2011,30(29):160-161
针对现有内河航运船舶过闸管理存在工作效率较低,安全性较差,服务不到位等问题,提出基于RFID和GSM的船舶过闸辅助调度系统。以船舶预调度和自动过闸方式对带有芯片的船舶进行自动识别,读取数据;对遇到相关异常情况及时进行处理;根据船舶相关属性信息安排过闸调度,实现自动收费。并对该系统的基本工作原理、整体结构和实现方案等问题进行论述。  相似文献   
7.
以船舶工业为特色的数字资源库建设探讨   总被引:1,自引:0,他引:1  
王翠华 《价值工程》2011,30(21):237-238
阐述了我校图书馆在学校办学过程中形成的以船舶工业为特色的独特的馆藏资源,通过对学校在教学科研所获得的成果进行收集、整理,探讨在此基础上建立数字资源库及必须注意的问题。  相似文献   
8.
This paper presents a simulation-based modelling approach for estimating total visitor numbers and amenity values for prospective non-priced open-access outdoor recreation sites. To begin, the geographic extent of the market for recreation at a policy site is estimated using data from a similar study site. The population residing within this geographic area is simulated using a spatial microsimulation model and GIS techniques and an individual-level ‘visitor arrival function’ is then transferred across this simulated population. This allows the latent demand for visits to the policy site by each simulated individual to be predicted and summed, providing an estimate of the total potential demand for recreation at the site. Combining this with an economic value measure of a visit provides an estimate of the potential amenity value of the policy site. The approach is applied to Moyode Wood, a small-scale forest in the West of Ireland, and estimates the potential total economic value of recreation at €0.4 million for the site. The research represents the first time that spatial microsimulation has been used in environmental benefit transfer and shows how it can be used to control for differences in demographic and spatial factors between study and policy sites. It also demonstrates how individual-level single-site travel cost models estimated using on-site survey data can be used to predict demand at alternative policy sites.  相似文献   
9.
近年来我国的民营船厂发展迅速,但由于民营船厂缺乏足够的资金和信用能力,大多采用由外贸公司承担对外开立预付款银行保函和提供信用担保的出口代理角色.本文分析了这种模式下外贸公司承担的风险,并提出了应采取的风险防范措施.  相似文献   
10.
ABSTRACT

The effects of gender on involvement in high-risk recreation have received limited research attention despite mounting evidence suggesting the learned interactions between people and places likely vary for men and women. The purpose of this study was to provide insights into how gender influenced the motivation-involvement relationship among whitewater recreationists on a Wild and Scenic River in California. Our results revealed the motivations of Risk, Escape, Learning, and Achievement/Stimulation positively influenced involvement in rafting activities. Although gender did not influence all dimensions of involvement, we found that identity expression varied between subgroups. Specifically, men were more likely to ascribe meaning to rafting than women because this activity allowed them to affirm and express their individual character. The implications emanating from this study advance theoretical understanding of the factors that influence enduring involvement and inform natural resource management decisions about maintaining the desired benefits of activities sought by nature-based recreationists.  相似文献   
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