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Evaluation of the ecological status with benthic indices in the coastal system: the case of Bohai Bay (China)

Wenqian CAI,Wei MENG,Lusan LIU,Kuixuan LIN

《环境科学与工程前沿（英文）》 2014年第8卷第5期页码 737-746 doi: 10.1007/s11783-013-0617-x

摘要： Based on biologic and environmental materials collected from coastal areas of Bohai Bay (China) in April, 2008, three biotic indices (AZTI’s Marine Biotic Index (AMBI), Shannon–Wiener Index and -statistic) were applied together to evaluate the ecological status of the sampling area. The results showed a clear spatial gradient from a worse ecological status in the near-shore areas (especially around Haihe and Jiyun River Estuaries) to a better status in the offshore areas. While all the three indices could assist decision makers in visualizing spatial changes of organic pollutants in Bohai Bay, two indices, i.e., AMBI and Shannon-Wiener index, were effective in distinguishing sites from Haihe River Estuary, Jiyun River Estuary and other area. However, -statistic can’t tell the differences between estuaries and other area. It would be explained that organic pollutants and/or other environmental stresses in Bohai Bay were not strong enough to reduce the size of macrozoobenthos, which may cause both of the abundance and biomass curves crossed. To our knowledge, this is the first time that several benthic indices were used to assess the benthic ecological status in Bohai Bay, which gave the similar results. Furthermore, there is indication that the ecological status is related to excess input of wastewater along main rivers and outlets. In a word, AMBI, Shannon–Wiener Index and -statistic could be able to assess the benthic ecological status of Bohai Bay under the organic pollutants pressure.

关键词： AZTI’s Marine Biotic Index Shannon-Wiener Index W-statistic ecological status coastal system Bohai Bay (China)

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热作模具钢的原位统计分布分析

王海舟,李美玲,张秀鑫,吴超

《中国工程科学》 2009年第11卷第10期页码 39-47

摘要：

采用原位统计分布分析技术对不同来源的模具钢进行解析，获得了模具钢坯横剖面较大尺度范围内各化学组成的位置分布、状态分布、含量分布的一系列新信息；定量表征了不同来源模具钢的最大偏析度、统计偏析度、统计符合度、统计致密度、统计疏松度、夹杂物种类和含量以及粒度统计分布等参数的差异性，可用于不同来源模具钢质量差异解析的参考。

关键词：原位统计分布分析模具钢统计偏析度统计符合度夹杂

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高温合金压气机盘锻件纵断面中铌分布的原位统计分布分析表征

王海舟,李美玲,庄景云

《中国工程科学》 2011年第13卷第10期页码 19-27

摘要：

采用原位统计分布分析表征技术系统研究了GH169高温合金压气机盘纵断面不同部位铌分布的规律。以所得到的与样品原位置相对应的数以万计原始信号系统解析为基础，进而获得压气机盘锻件的纵断面不同部位铌的定量统计分布信息以及加工工艺过程中铌的迁移规律。准确计算判定了盘纵断面不同部位铌的最大偏析度，提出了95 %置信度时中位值置信扩展率,即统计偏析度（S）新参数，用以表征铌在压气机盘中分布的均匀度；提出了所有数据在特定含量区间（C₀±R）的频度（权重）比率，即统计符合度（F）新参数，用以表征预设质量控制区间铌含量的一致性的概率。采用原位统计分布分析的表征方法，准确定量地评定了高温合金压气机盘件纵断面不同部位铌的分布均匀度和符合度，为加工后盘件的质量控制评估提供了参考。

关键词：原位统计分布分析表征技术高温合金压气机盘铌统计偏析度统计符合度质量控制

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连铸钢坯质量的原位统计分布分析研究

王海舟,李美玲,陈吉文,吴超

《中国工程科学》 2003年第5卷第10期页码 34-42

摘要：

采用原位统计分布分析技术得到与样品原位置相对应的数以万计原始信号并对其进行系统解析，实现不同质量连铸钢坯试样的疏松度、均匀度以及夹杂物含量的定量表征。准确计算了连铸钢坯试样疏松度、碳元素的最大偏析度。提出铸坯各原位置成分含量的权重比率方法用以表征材料的均匀度，并提供了统计分布允许差范围内（C₀±R）所占权重比率以及权重比率为95%置信度时，中位值置信扩展率（K）等2种判断模式。该方法以测量信息的原始性、原位性及统计性为特征，反映了连铸钢坯较大尺度范围内各化学组成及其形态的定量统计分布规律。采用上述方法可以合理解释连铸钢坯之间的质量差异性，可作为连铸钢坯质量的判断依据。

关键词：原位统计分布分析连铸钢坯疏松度均匀度夹杂物

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关于面向智能制造的设计的若干思考

David W. Rosen

《工程（英文）》 2019年第5卷第4期页码 609-614 doi: 10.1016/j.eng.2019.07.011

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Analysis on the distinguishing features of traditional Chinese therapeutics and related statistical issues

Jingqing Hu, Jie Qiao, Deying Kang, Baoyan Liu

《医学前沿（英文）》 2011年第5卷第2期页码 203-207 doi: 10.1007/s11684-011-0138-6

摘要： Traditional Chinese medicine (TCM) is one of the rarely existing ancient traditional medicines that hold systematic theories as well as preventative and therapeutic methods for diseases in practice. From the 1950s, such research methods as mathematics, statistics, and data mining (DM) have been gradually introduced to TCM studies, making it more scientific. Meanwhile, the distinct features of TCM theories and diagnostic-model have constantly challenged the methodology of statistics. This paper introduces the following scientific features of traditional Chinese therapeutics: 1) its goal is to balance the functions and conditions of human body; 2) it emphasizes on holism and individualization; 3) it stresses the longitudinal regulation and evaluation mode, which is a circle of syndrome diagnosis, treatment and evaluation; 4) the interventions of TCM are abundant, compound and natural; and 5) humanistic thought is everywhere. Some statistical problems are raised based on these features. First, complex statistical methods that can analyze subjective indexes and latent variables, multidimensional and multistage data, non-equilibrium designed studies, and longitudinal data are required. Second, comprehensive evaluation on multiple-target mechanism has been brought in by combination treatment. Third, there is a need to analyze how humanity and related cultural factors may influence the effect of interventions. Thus, promoting implemented studies of statistics as well as carrying out the TCM scientific propositions have become the common expectations of both TCM and modern medicine.

关键词： traditional Chinese therapeutics feature statistic

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Liver surgery and transplantation in China: Progress and Challenges

LAU W Y, LAI E C H

《医学前沿（英文）》 2007年第1卷第1期页码 1-5 doi: 10.1007/s11684-007-0001-y

摘要： From the limited but available information, we traced the history of developments of liver surgery and transplantation in China. Liver surgery first started in the late 1950s in China, and it soon flourished mainly because of the great demand in liver surgery and the emergence of a number of giants in liver surgery. We recognized and honoured the important contributions of these Chinese pioneers in portal hypertension, recurrent pyogenic cholangitis, hepatocellular carcinoma and liver transplantation.

关键词： transplantation pyogenic cholangitis available information important hypertension

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Ground movements due to deep excavations in Shanghai: Design charts

VARDANEGA,Charles W. W. NG,Xianfeng MA

《结构与土木工程前沿（英文）》 2014年第8卷第3期页码 201-236 doi: 10.1007/s11709-014-0253-y

摘要： Recent research has clarified the sequence of ground deformation mechanisms that manifest themselves when excavations are made in soft ground. Furthermore, a new framework to describe the deformability of clays in the working stress range has been devised using a large database of previously published soil tests. This paper aims to capitalize on these advances, by analyzing an expanded database of ground movements associated with braced excavations in Shanghai. It is shown that conventional design charts fail to take account either of the characteristics of soil deformability or the relevant deformation mechanisms, and therefore introduce significant scatter. A new method of presentation is found which provides a set of design charts that clarify the influence of soil deformability, wall stiffness, and the geometry of the excavation in relation to the depth of soft ground.

关键词： Shanghai excavations mobilizable strength design dimensionless groups design charts

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Robotized machining of big work pieces: Localization of supporting heads

Wojciech SZYNKIEWICZ, Teresa ZIELIŃSKA, Włodzimierz KASPRZAK

《机械工程前沿（英文）》 2010年第5卷第4期页码 357-369 doi: 10.1007/s11465-010-0103-0

摘要： A planner for a self adaptable and reconfigurable fixture system is proposed. The system is composed of mobile support agents that support thin sheet metal parts to minimize part dimensional deformation during drilling and milling operations. Compliant sheet metal parts are widely used in various manufacturing processes including automotive and aerospace industries. The main role of the planner is to generate an admissible plan of relocation of the mobile agents. It has to find the admissible locations for the supporting heads that provide continuous support in close proximity to the tool and trajectories of the mobile bases characterized by very high speeds during the relocation phases.

关键词： fixture robot milling drilling

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A small-scale silica gel-water adsorption system for domestic air conditioning and water heating by the recovery of solar energy

W. PAN, L. W. WANG

《能源前沿（英文）》 2020年第14卷第2期页码 328-336 doi: 10.1007/s11708-019-0623-1

摘要： A small-scale silica gel-water adsorption system with modular adsorber, which utilizes solar energy to achieve the cogeneration of domestic air conditioning and water heating effect, is proposed and investigated in this paper. A heat recovery process between two adsorbers and a mass recovery process between two evaporators are adopted to improve the overall cooling and heating performance. First, the adsorption system is tested under different modes (different mass recovery, heat recovery, and cogeneration time) to determine the optimal operating conditions. Then, the cogeneration performance of domestic cooling and water heating effect is studied at different heat transfer fluid temperatures. The results show that the optimal time for cogeneration, mass recovery, and heat recovery are 600 s, 40 s, and 40 s, respectively. When the inlet temperature of hot water is around 85°C, the largest cooling power and heating power are 8.25 kW and 21.94 kW, respectively. Under the condition of cooling water temperature of 35°C, the obtained maximum COP , COP , and SCP of the system are 0.59, 1.39, and 184.5 W/kg, respectively.

关键词： silica gel-water heat and mass recovery solar energy domestic cooling and heating

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Barriers to advancing nanotechnology to better improve and translate nanomedicines

Yuwei WANG,David W. Grainger

《化学科学与工程前沿（英文）》 2014年第8卷第3期页码 265-275 doi: 10.1007/s11705-014-1442-x

摘要： Engineered nanomaterials and nanotechnologies promise many benefits to enhance both and performance. This is now manifest in the increasing number of reported biomedical products under development and testing that contain nanotechnologies as their distinguishing performance—enhancing components. In many cases, nano-sized materials are selected to provide a specific functional aspect that contributes to improved medical performance, either or . Nanoparticles are most commonly exploited in diverse roles in topical lotions and creams, solubilization aids, for and diagnostic and targeting agents in nanomedicines and theranostics. Despite fundamental scientific excitement and many claims to nanotechnology-based improvements in new biomedical applications, several fundamental and long-standing challenges remain to be addressed using nanomedicines to make clinically important progress. This review addresses several issues that must be fairly and objectively reported and then overcome to provide truly credible performance for nanomedicines.

关键词： nanotechnology nanomedicine drug delivery therapeutic target delivery

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V-W-Mo-Cu催化剂作用下生物质醇解重油加氢精制研究

邹献武,秦特夫,李改云,黄洛华

《中国工程科学》 2014年第16卷第4期页码 69-73

摘要：为此，本文考察了V-W-Mo-Cu 催化剂作用下重油的加氢精制。结果表明，在330 ℃以上该催化剂才表现出加氢反应活性，在450 ℃时轻油产率最高可到93 %。

关键词：生物质醇解重油加氢 V-W-Mo-Cu催化剂图像处理

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Evolving perspectives on biofuels in the United States

DIRKS, Gary W. DIRKS, Jianguo WU

《能源前沿（英文）》 2012年第6卷第4期页码 379-393 doi: 10.1007/s11708-012-0213-y

摘要： Biofuels represent an important source of renewable energy and may play a crucial role in developing sustainable energy strategies for many countries and the world as a whole. The pros and cons of biofuels, however, have been debated both scientifically and politically. They remain a topic of controversy. In this paper, the evolvement of the perspectives and policies on biofuels in the United States in the past several decades was reviewed. Four different periods, that is, the period prior to 1978 (marked by the passage of the Energy Act in 1978); 1978–1989 (ending with the passage of the Clean Air Act Amendments of 1990); 1990–2004 (ending with the passage of the energy act of 2005); and 2005 to the present, which were characterized by defining events of major policy importance were identified. Each time period was assessed using the Ostrom institutional analysis and development (IAD) framework to show the impact of the evolving interests and influences of global players on policy choices related to biofuels in the United States. The US has a long history of supporting corn-based ethanol and more recently advanced biofuels. Changes in perspectives on biofuels from largely unrelated groups led to changes in policy and market dynamics. Until the late 1990s, most perspectives and policies tended to be aligned and significantly supportive of corn-based ethanol in the United States. In the early 2000s, it became clear that the complications associated with first generation biofuels and corn-based ethanol in particular, were too numerous and too severe to overlook. The need for better options has spurred interest in new technologies and more environmentally benign feedstocks, but, there is little prospect for biofuels playing a significant role in the near term without greater alignment among key players.

关键词： renewable energy biofuels energy sustainability

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Erratum to: Industrial water treatment and industrial marine outfalls: Achieving the right balance

Adrian W. K. Law, Chunyan Tang

《化学科学与工程前沿（英文）》 2017年第11卷第2期页码 290-290 doi: 10.1007/s11705-017-1639-x

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Changes in hourly precipitation may explain the sharp reduction of discharge in the middle reach of the Yellow River after 2000

Lin LUO, Zhongjing WANG

《环境科学与工程前沿（英文）》 2013年第7卷第5期页码 756-768 doi: 10.1007/s11783-013-0563-7

摘要： The Hekou-Longmen reach, together with local floods, is the main source area for coarse sedimentations into the Yellow River. When total rainfall slightly increased in the area, discharge dramatically decreased by 40%–70% after the year of 2000, and attracting extensive attention in the context of global climate change. High temporal resolution precipitation (timescales between 1 and 4 h) data from the June to September period from 270 rain gauges over the past three decades was mined in order to help explain the phenomenon. Each rainfall event was classified as light/moderate rain, large rain, heavy rain or rainstorm by the event’s rainfall amount, and further classified as low intensity rain, medium intensity rain and high intensity rain by the event’s rainfall intensity. The Mann-Kendall trend test was applied to detect the presence and significance of monotonic trends, and to find the change points in the mean and variance of the precipitation characteristics series, including the amount, intensity, frequency and duration of each rainfall category. Results show that although the total amount of precipitation has slightly increased, the average rainfall intensity has significantly decreased. The larger change happened in light/moderate rain events and low/medium intensity rain events, and the intensity changes have a great extent occurred around the threshold of Non-Runoff Rainfall regime, which was proposed for the approximate calculation of initial losses. Changes in rainfall distribution between different classes of the Runoff Rainfall regime in the 2000s could lead to 0.9 mm less runoff depth (17.3% of the total reduction) than the 1980–1999 period. The study indicates that changes in hourly precipitation may be responsible for the sharp reduction of discharge.

关键词： precipitation intensity Mann-Kendall rank statistic spatial and temporal distribution climatic change