基于慢特征分析的分布式动态工业过程运行状态评价

现代工业过程通常具有规模大、流程长和工序多的特点,导致传统的集中式建模方法会淹没过程的局部变化信息,从而无法及时识别早期的非优运行状态.此外,闭环控制的广泛应用使得过程变量普遍存在时序相关性.针对以上问题,提出一种基于慢特征分析(Slow feature analysis, SFA)的分布式动态工业过程运行状态评价方法.首先,结合动态时间规整(Dynamic time warping, DTW)和K-medoids聚类算法对过程进行分解;然后,对每一变量子块建立相应的动态慢特征分析(Dynamic slow feature analysis, DSFA)模型;最后,利用贝叶斯推理获得全局的综合评价指标.通过在数值案例和金湿法冶金过程的仿真应用,验证了该方法的有效性.

基于改进随机森林算法的工业过程运行状态评价

运行状态评价是指在过程正常生产的前提下,进一步判断生产过程运行状态的优劣.针对复杂工业过程定量信息与定性信息共存的情况,本文提出了一种基于随机森林的工业过程运行状态评价方法.针对随机森林中决策树信息存在冗余的问题,基于互信息将传统随机森林中的决策树进行分组,并选出每组中最优的决策树组成新的随机森林.同时为了强化评价精度高的决策树和弱化评价精度低的决策树对最终评价结果的影响,使用加权投票机制取代传统众数投票方法,最终构成一种基于互信息的加权随机森林算法(Mutual information weighted random forest,MIWRF).对于在线评价,本文通过计算在线数据处于各个等级的概率,并且结合提出的在线评价策略,判定当前样本运行状态等级.为了验证所提算法的有效性,将所提方法应用于湿法冶金浸出过程,实验结果表明,相对于传统随机森林算法,MIWRF降低了模型的复杂度,同时提高了运行状态评价精度.

乡村世界遗产特征与价值研究

世界遗产缺乏对乡村类型遗产的划分导致对此类遗产特征与综合价值的把握不甚明确。乡村是由其所在地的自然基底要素、硬质要素和软质要素共同作用形成的综合体,记录了乡村人类活动的历史,表达了特定乡村地域的独特精神。文章筛选了28处独立且仍有人类活动的乡村世界遗产,通过梳理文献资料归纳了不同地域的乡村世界遗产特征,并且总结了乡村规划布局、文化艺术、杰出建筑和土地利用4大核心价值。进而指出,我国的乡村世界遗产申遗工作起步较晚,且地域局限、类型单一,未来乡村世界遗产申报可尝试从其他遗产亚类或者双遗产角度开展,发掘乡村地域的自然生态环境、手工业生产方式等价值,丰富我国乡村世界遗产类型和价值。并且,我国在城镇化进程中应当格外注重对乡村世界遗产的保护。

Rural Tourism Development in China:Principles,Models and the Future

Rural tourism in China,has undergone a rapid development in the last three decades.It is an emerging and effective catalyst that promotes industrial restructuring,agricultural development and the upgrading of rural areas.However,there remains little understanding about the core issues of rural tourism in China:the exact connotation,the principles,the development models and the future directions.This review paper identifies the key issues based on literature analysis,national statistics and press reports to form a general picture of the past,the current and the future prospects of China's rural tourism.The paper firstly addresses the definition,content and principles of rural tourism,and then provides an overview and brief evaluation of the progress and the current development models in China.Finally,based on the analysis of the experiences and problems,the authors sum up with five pathways of the future development of China's rural tourism from the perspective of rural tourism resources,product,market and promotion.

The ideal landscape and its ecological planning approach in Mount Lushan National Park, China

This paper described the main four basic models of ideal landscape in the Mount Lushan National Park as Kunlunshan model, Xumishan model, Peach flower land model, Christian model. Five typical places in Mount Lushan with the ideal landscape characteristics like the East Grove Temple, White Deer Cave Academy, Simplicity and Tranquility Monastery, Lushan Valley, and Villa-cluster of the East Valley were analyzed, and the integration of the basic models for each place was discussed to make the realistic landscape conform to the ideal needs. Moreover, the discussions also involved the characteristics of ideal landscape that are featured in resource, culture, structure, function, process, scale and region. In conclusion, ideal landscape in the Mount Lushan National Park was the product of the interaction between human and nature. Mount Lushan inherits the essence of Chinese traditional culture with a history of more than 1000 years; and it also absorbs the manna of the Western culture as well as the exchanges between nature and humanities together with the conflict and adaptation among different cultures. The natural landscape could be satisfied with the survival demand and cultural taste of mankind by the way of ecological planning.

Analysis on low-cost airlines and tourism development

Low-cost airlines offered cheap fares in exchange eliminating many traditional passenger services.Cheap air transport was considered as an enabling or permissive factor for regional tourism,The most obvious effect was the growth of tourists' amount to a destination and the concomitant changing of visitors market.Additionally,with the development of low-cost airlines,the updated operation means such as on-line booking system enhanced competition ability against traditional sales agent.The selection model of airports,which were gateway for low-cost airlines' entrance to region or tourism destination,would determine the intense relationship between low-cost airlines and tourism.As international low-cost airlines gradually changed their selection from traditional secondary airports and involved into spokehub airports,the operation business model of low-cost airlines diversified as well.Typical international case of low cost airlines in south pacific region was analyzed.Besides,Spring Airlines which was the first low-cost airlines in China was illustrated as well.Further research should focus on a quantitative study on relationship among low-cost airlines,airports distribution and tourism development.

基于搜索算法的前传Delta-Sigma调制器优化设计

针对目前移动前传中使用的通用公共无线电接口(CPRI)技术频谱效率不高的问题,文章提出使用Delta-Sigma调制(DSM)技术作为一种新的前传接口。另外,针对高阶稳定Delta-Sigma调制器参数搜寻中计算复杂度过高问题,使用遗传算法对所使用的四阶Delta-Sigma调制器的结构参数进行了搜索优化,并将该优化结构参数下的仿真结果与原结构参数下的仿真结果进行了比较。在1 bit量化的情况下,使用优化参数的Delta-Sigma调制器增大系统传输容量的同时,平均误差向量幅度(EVM)从0.031下降到0.028;在2 bit量化的情况下,平均EVM从0.013下降到0.011。

中国国家公园建设潜在区域识别研究

国家公园是保护具有国家代表性资源的自然生态区域,建设国家公园体制是中国国土生态安全保障和生态文明体制改革的重要内容。论文基于国际经验、国家公园功能和政策内涵,依据国家公园主导定位和生态系统服务理念,构建了包含6个关键指标的综合评价模型,包括生态系统完整性、生态重要性、原真性、生物多样性、自然景观价值与人文遗产价值,分别进行单一要素层评价和多指标空间叠加分析,再结合中国生态地理区划、生态功能区划和省级行政区管理等因素进行比对和范围遴选提取,初步确定了中国国家公园建设的潜在区域。结果表明,生态系统完整性、生态重要性、生物多样性、原真性的高值集聚区域具有趋同性,生态系统完整性较好的区域,承担着重要的生态功能,生物多样性也较高,原真性保存较好。中国三大阶梯与自然地理区域的叠加分布特征明显,东西部潜在区域的面积差异较大,西部地区的空间连续性较强,潜在区域的跨界性较为明显。初步遴选出55处未来可以重点考虑建设的陆地型国家公园潜在区域。研究可为中国国家公园建设合理布局提供方法参考和理论借鉴。

国外气候变化对旅游业影响的定量研究进展与启示

加强气候变化对旅游业影响的定量研究,有助于旅游业在气候变化背景下实现可持续发展。基于SCI/SSCI文献数据库,梳理分析国外气候变化对旅游业影响的定量研究进展。结果显示,30余年来国外主要采用指标方法、需求模型与选择分析方法开展相关研究。20世纪80年代末出现的指标方法是运用最早、最广泛的方法,主要用于旅游资源环境变化等研究,呈现由单项指标转向综合指标的应用趋势;20世纪90年代末兴起的需求模型主要用于天气状况对旅游需求的影响等研究,呈现由时间序列模型转向累计需求模型的应用趋势;21世纪兴起的选择分析主要用于气候变化背景下的行为意愿等研究,呈现由描述统计转向离散选择模型的应用趋势。这些给我国研究的启示是:在研究方法与研究领域上,重点加强累计需求模型在旅游流相关研究中的运用,加强离散选择模型在旅游市场结构相关研究中的运用,加强系统科学方法与大数据技术在相关研究中的运用;在研究对象上,丰富中国境内气候敏感型旅游活动的相关研究,加强"一带一路"沿线国家、地区及青藏高原的相关研究。

农垦社区旅游投资意愿特征及其形成机制研究——以呼伦贝尔垦区为例

本文以内蒙古呼伦贝尔垦区为例,根据计划行为理论提出社区旅游投资意愿影响机制理论框架,并运用Pearson卡方检验、logistic回归等方法进行实证分析。结果表明:农垦社区旅游投资意愿具有3个特征:地理亲近性、中青主体性、生计路径依赖。这些特征的形成机制有6种:风险规避机制、前景期望机制、熟人传导机制、制度认同机制、效能促进机制与竞争激励机制。不同特征的形成机制既有相似、也有差异。具有不同客观条件的社群,其主观因素的作用机制既有相似、也有差异。该研究有助于丰富旅游地社区研究、推进中国农垦地区转型发展。