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Appraisal of coastal recreational resources in Qingdao by travel cost method

Jingmei LI , Tieying LIU , Yuanyuan ZHANG , Lei LI ,

《环境科学与工程前沿（英文）》 2009年第3卷第3期页码 341-347 doi: 10.1007/s11783-009-0038-z

摘要： This paper serves to appraise the monetary cost of coastal recreational resources in Qingdao using the travel cost method (TCM), which is typically used in developed countries. The total revenue produced by Qingdao’s coastal recreational resources is about RMB 5.51×10 annually, based on questionnaires given at Qingdao’s major tourist destinations. These questionnaires establish correlation functions that factor in the number of tourists, travel expenses, etc. The data processing software named Eviews was used to determine the tourist demand regression curve and to calculate their residual and actual travel expenses. The results of this study can provide a scientific basis for applicable industries interested in development and management decision-making. Therefore, this study assesses the reasonable usage of coastal recreational resources.

关键词： coastal recreational resources travel cost method (TCM) regression analysis Qingdao China

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Understanding network travel time reliability with on-demand ride service data

Xiqun (Michael) CHEN, Xiaowei CHEN, Hongyu ZHENG, Chuqiao CHEN

《工程管理前沿（英文）》 2017年第4卷第4期页码 388-398 doi: 10.15302/J-FEM-2017046

摘要： Travel time reliability is of increasing importance for travelers, shippers, and transportation managers because traffic congestion has become worse in major urban areas in recent years. To better evaluate the urban network-wide travel time reliability, five indices based on the emerging on-demand ride service data are proposed: network free flow time rate (NFFTR), network travel time rate (NTTR), network planning time rate (NPTR), network buffer time rate (NBTR), and network buffer time rate index (NBTRI). These indices take into account the probability distribution of the travel time rate (i.e., travel time spent for the unit distance, in min/km) of each origin-destination (OD) pair in the road network. We use real-world data extracted from DiDi-Chuxing, which is the largest on-demand ride service platform in China. For demonstrative purposes, the network-wide travel time reliability of Beijing is analyzed in detail from two dimensions of time and space. The results show that the road network is more unreliable in AM/PM peaks than other time periods, and the most reliable time period is the early morning. Additionally, we can find that the central region is more unreliable than other regions of the city based on the spatial analysis results. The proposed network travel time reliability indices provide insights for the comprehensive evaluation of the road network traffic dynamics and day-to-day travel time variations.

关键词： network travel time reliability on-demand ride services travel time rate OD

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试论中医学的性质与特点，中医理论的形成与发展

李连达,靖雨珍

《中国工程科学》 2005年第7卷第7期页码 24-26

摘要：

论述了中医学的性质与特点，以及中医理论的形成与发展。中医理论来源于实践，是古人长期与疾病斗争的大量实践，从实践经验的积累、综合到感性认识上升为理性认识，并广泛借鉴古代哲学、人文科学的思想、方法、世界观，逐渐形成以整体观为特点的系统化、理论化的中医理论；强调了中医药现代化的目的是全面提高中医药防病治病能力，不断发展创新；讨论了中医理论现代化的内容、重点及注意事项进行。

关键词：中医学中医药现代化阴阳五行、天人合一太极八卦

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Translating the power of TCM into patients’ hope

null

《医学前沿（英文）》 2014年第8卷第3期页码 265-267 doi: 10.1007/s11684-014-0329-z

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确立中医药战略地位的重要意义

贾谦,陈永杰,陈光曼,杨巨平,应光荣

《中国工程科学》 2004年第6卷第7期页码 4-13

摘要：

中医学以“天人相应”、“阴阳平衡”为哲学基础，以“整体观念”、“辨证论治”为主要特点，以中药、针灸等为主要治疗手段来调整、激发人体的自我康复能力，纠正人体的偏常之性而达到防病治病目的。中医学所提倡的人与自然（包括细菌、病毒等）和谐共处，而不是对微生物大规模灭活的理念，维持了微生物与人类之间微妙的生理平衡，这正是医学未来的发展方向。千百年来，中医药为中华民族的繁衍昌盛做出了不可磨灭的贡献，使其在无数次瘟疫的侵袭下从未像欧洲一样一死上千万人；同时，中医药“简便廉验”，在预防和治疗慢性病、多因素复杂性疾病以及新型病毒性疾病等方面尤有所长，故只有建立中西医并重的卫生保健体系，才能保障中国13亿人口的健康，才能解决9亿农民和城市贫困人口的缺医少药问题。建议实施“中医药五大振兴工程”，即中医药政策法规保障工程、中医药人才工程、中医药科研工程、乡村中医工程以及中医药行政管理体制改革工程，以做到中医药的可持续发展。

关键词：中医学中医药政策中医药人才乡村中医工程中医药管理体制改革

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Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

《机械工程前沿（英文）》 2017年第12卷第2期页码 265-278 doi: 10.1007/s11465-017-0453-y

摘要：

Most of the XY positioning stages proposed in previous studies are mainly designed by considering only a single performance indicator of the stage. As a result, the other performance indicators are relatively weak. In this study, a 2-degree-of-freedom linear compliant positioning stage (LCPS) is developed by mechatronic design to balance the interacting performance indicators and realize the desired positioning stage. The key parameters and the coupling of the structure and actuators are completely considered in the design. The LCPS consists of four voice coil motors (VCMs), which are conformally designed for compactness, and six spatial leaf spring parallelograms. These parallelograms are serially connected for a large travel range and a high out-of-plane payload capacity. The mechatronic model is established by matrix structural analysis for structural modeling and by Kirchhoff’s law for the VCMs. The sensitivities of the key parameters are analyzed, and the design parameters are subsequently determined. The analytical model of the stage is confirmed by experiments. The stage has a travel range of 4.4 mm× 7.0 mm and a 0.16% area ratio of workspace to the outer dimension of the stage. The values of these performance indicators are greater than those of any existing stage reported in the literature. The closed-loop bandwidth is 9.5 Hz in both working directions. The stage can track a circular trajectory with a radius of 1.5 mm, with 40 mm error and a resolution of lower than 3 mm. The results of payload tests indicate that the stage has at least 20 kg out-of-plane payload capacity.

关键词： mechatronic design linear compliant positioning stage large travel range high out-of-plane payload capacity spatial parallelogram voice coil motor sensitivity analysis

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A method to synthesize CdSe nanocrystals

XIE Chuang, CHEN Wei, WANG Jingkang

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 377-380 doi: 10.1007/s11705-007-0068-7

摘要： CdSe nanocrystals (NCs) have great application prospects in various fields due to their novel properties. Some high-cost and toxic materials such as --octylphosphine oxide (TOPO) are used in the popular method to synthesize CdSe NCs. Based on this, a new low-cost, environment-friendly and safe solvent was introduced in the synthesis of CdSe NCs in this paper. The prepared CdSe NCs were characterized by ultraviolet-visible spectra (UV-Vis), photoluminescence (PL), transmission electron micrograph (TEM), energy disperse X-ray spectra (EDX) and X-ray diffraction (XRD). The CdSe NCs obtained which show a good PL property are monodisperse, size-tunable and of high crystallinity. It indicates that the new solvent A is a good substitute for the solvent used in the classic route and achieves a greener synthesis of CdSe NCs.

关键词： octylphosphine greener synthesis substitute electron micrograph low-cost

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Middle East respiratory syndrome coronavirus: current situation and travel-associated concerns

null

《医学前沿（英文）》 2016年第10卷第2期页码 111-119 doi: 10.1007/s11684-016-0446-y

摘要：

The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 brought back memories of the occurrence of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002. More than 1500 MERS-CoV cases were recorded in 42 months with a case fatality rate (CFR) of 40%. Meanwhile, 8000 cases of SARS-CoV were confirmed in six months with a CFR of 10%. The clinical presentation of MERS-CoV ranges from mild and non-specific presentation to progressive and severe pneumonia. No predictive signs or symptoms exist to differentiate MERS-CoV from community-acquired pneumonia in hospitalized patients. An apparent heterogeneity was observed in transmission. Most MERS-CoV cases were secondary to large outbreaks in healthcare settings. These cases were secondary to community-acquired cases, which may also cause family outbreaks. Travel-associated MERS infection remains low. However, the virus exhibited a clear tendency to cause large outbreaks outside the Arabian Peninsula as exemplified by the outbreak in the Republic of Korea. In this review, we summarize the current knowledge about MERS-CoV and highlight travel-related issues.

关键词： coronavirus MERS Middle East respiratory syndrome

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Influence of infiltration on energy consumption of a winery building

Hejiang SUN, Qingxia YANG

《能源前沿（英文）》 2014年第8卷第1期页码 110-118 doi: 10.1007/s11708-013-0293-3

摘要： With the wide use of light steel structure in industrial buildings, some problems such as air leakage, water dripping and condensation and so forth occur during the construction and operation phases. Through the onsite testing of a winery building in Huailai County, Hebei Province in China, the influence of infiltration on energy consumption in industrial buildings was studied. The pressurization test method and moisture condensation method were used to test the infiltration rates. The results show that the winery building is twice as leaky as normal Chinese buildings and five times as leaky as Canadian buildings. The energy use simulation demonstrates that the reduction of the infiltration rate of the exterior rooms to 1/3 and the interior rooms to 1/2 could help decrease a total energy consumption of approximately 20% and reduce a total energy cost of approximately $ 225000. Therefore, it has a great potential to reduce the energy consumption in this type of buildings. Enforcement of the appropriate design, construction and installation would play a significant role in improving the overall performance of the building.

关键词： industrial building air change rate pressurization test method moisture condensation method energy cost

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一种适用于自动驾驶汽车的多层地图模型和车道级轨迹规划 Article

江昆, 杨殿阁, 柳超然, 张涛, 肖中阳

《工程（英文）》 2019年第5卷第2期页码 305-318 doi: 10.1016/j.eng.2018.11.032

摘要：

越来越多的司机依赖于汽车或手机上的电子地图导航系统来选择最佳的驾驶路线，以节省时间和提高安全性，在不久的将来，电子地图和导航系统有望在未来交通运输系统中发挥更大的作用。为了将现有的导航系统扩展到更多的应用领域，如自动驾驶，需要考虑在传统道路地图模型的基础上，建立车道级地图模型和车道级轨迹规划。本研究针对传统电子地图内容不够丰富的局限性，提出了一种全新的七层自动驾驶地图结构模型，并将它命名为清华地图模型。考虑车辆换道、转向和直行等不同行车特点，建立了车道级路段行车代价模型，建立一种分层路径轨迹搜索方法，能够在道路和车道网络中实现快速的轨迹规划，能够很好地支持自动驾驶的车道级轨迹规划。通过在虚拟道路网络和实际道路网络上的测试，充分验证了该地图模型和算法的灵活性和有效性。

关键词：车道级地图路径规划清华地图模型行车代价模型

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中医论治艾滋病

王文奎

《中国工程科学》 2004年第6卷第1期页码 44-47

摘要：

严重的细胞免疫功能缺陷是艾滋病发生的内因，获得性的病毒是外因，外因只有通过内因才能致病。而细胞免疫缺陷的根本，全在于生养细胞的条件与环境。一切条件全靠人体的脏腑功能运动来创造，只有宏观而整体的调控人体的脏腑功能运动，才能化生人体所需要的一切物质。有了物质才能化生精神，有了物质和精神才能保障细胞的免疫功能，才能战胜并消灭各种病毒，才能恢复人体的身心健康，增强人体的免疫功能，保障人体的生命运动正常进行。

关键词：中医论治辨证艾滋病

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中医的渊源和对中医学发展的思考

王文奎,王峰,王岭

《中国工程科学》 2006年第8卷第4期页码 1-11

摘要：

传统的中医学源远流长，博大精深，疗效显著，由于种种历史原因，加之自身流派众多，传承艰难，流传至今，已不能满足现代社会的发展与要求。中医要发展，须走“医学衷中纳西”的与时俱进之路。中医自身要统一理论认识，统一辩证纲领，统一到“五脏阴阳”之中，以“三维守恒”指导辩证，要明确医学的目的，认识生命的本质和生命运动的机制；要宏观与微观相结合，整体与局部相统一，以唯象涵盖唯物，以辩证指导分析，以调为本，以平为期；要司岁备药，先法制病，对中药剂型进行改进，以适应社会发展的需要。

关键词：中医发展历程与现状衷中纳西中药剂型

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超声速客机计划再次登上历史舞台

Sean O’Neill

《工程（英文）》 2022年第10卷第3期页码 1-3 doi: 10.1016/j.eng.2022.01.004

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Future urban transport management

《工程管理前沿（英文）》页码 534-539 doi: 10.1007/s42524-023-0255-3

摘要： The incorporation of disruptive innovations into the transportation industry will inevitably cause major upheavals in the transportation sector. However, existing research lacks systematic theories and methodologies to represent the underlying characteristics of future urban transport systems. Furthermore, emerging modes in urban mobility have not been sufficiently studied. The National Natural Science Foundation of China (NSFC) officially approved the Basic Science Center project titled “Future Urban Transport Management” in 2022. The project members include leading scientists and engineers from Beijing Jiaotong University, Beihang University, and Beijing Transport Institute. Based on a wide range of previous projects by the consortium on urban mobility and sustainable cities, this project will encompass transdisciplinary and interdisciplinary research to explore critical issues affecting future urban traffic management. It aims to develop fundamental theories and methods based on social and technological developments in the near future and explores innovative solutions to implement alongside these emerging developments in urban mobility.

关键词： future urban transport management travel behavior characteristics transportation operations transportation emergency management transportation decision intelligence