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process of pure titanium with multiple performance characteristics using Taguchi’s DOE approach and utilityconcept

Rupesh CHALISGAONKAR, Jatinder KUMAR

《机械工程前沿（英文）》 2013年第8卷第2期页码 201-214 doi: 10.1007/s11465-013-0256-8

摘要：

This paper describes the development of multi response optimization technique using utility method to predict and select the optimal setting of machining parameters in wire electro-discharge machining (WEDM) process. The experimental studies in WEDM process were conducted under varying experimental conditions of process parameters, such as pulse on time(T_on), pulse off time(T_off), peak current (IP), wire feed (WF), wire tension (WT) and servo voltage (SV) using pure titanium as work material. Experiments were planned using Taguchi’s L27 orthogonal array. Multi response optimization was performed for both cutting speed (CS) and surface roughness (SR) using utility concept to find out the optimal process parameter setting. The level of significance of the machining parameters for their effect on the CS and SR was determined by using analysis of variance (ANOVA). Finally, confirmation experiment was performed to validate the effectiveness of the proposed optimal condition.

关键词： wire electro-discharge machining (WEDM) Taguchi method analysis of variance (ANOVA) utility concept cutting speed (CS) surface roughness (SR)

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网络系统行为效用计算——概念与原理 Article

胡昌振

《工程（英文）》 2018年第4卷第1期页码 78-84 doi: 10.1016/j.eng.2018.02.010

摘要：

网络的服务与应用是一个面向业务与任务的行为过程，其度量与评估目前尚处于粗略比较状态。本文把网络行为场景刻画为微分流形，根据光滑微分流形的同胚变换，给出了网络行为的数学定义，提出了网络行为路径及行为效用的数学描述。基于微分几何原理，提出了网络行为效用的计算原理与方法，并构建了基于行为效用的网络攻防对抗评估计算框架，从而奠定了网络行为定量度量和评估的数学基础。

关键词：网络度量评估微分流形网络行为效用网络攻防对抗

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Large eddy simulation of a 660 MW utility boiler under variable load conditions

Haoshu SHEN, Yuxin WU, Minmin ZHOU, Hai ZHANG, Guangxi YUE, Junfu LYU

《能源前沿（英文）》 2021年第15卷第1期页码 124-131 doi: 10.1007/s11708-020-0659-2

摘要： Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady features and turbulent structures of coal jet flame than Reynolds averaged Navier Stokes (RANS). The coal-fired power plants in China are now required to be operated in a wide load range and quickly respond to the electric grid. The boiler performance of variable loads should be evaluated in terms of flow, heat transfer, and combustion processes. In this paper, LES was applied to simulate a 660 MW ultra-supercritical boiler under BMCR (boiler maximum continue rate), 75%THA-100, and 50%THA-100 conditions. The predicted gas velocities agree well with the thermal calculation and the temperature error is less than 130 K. The simulation results show that the operation load has significant effects on the boiler performance. It is also proved that LES can provide guidance for the design and operation of advanced coal-fired boilers.

关键词： large eddy simulation ultra-supercritical boiler operation load

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Temperature and structural responses of a single-section utility tunnel throughout fire exposure

Yanmin YANG; Ying XIONG; Yongqing LI; Xiangkun MENG; Peng WANG; Tianyuan CAI

《结构与土木工程前沿（英文）》 2022年第16卷第10期页码 1351-1364 doi: 10.1007/s11709-022-0857-6

摘要： In this study, fire tests of four single-section scaled-down utility tunnels were conducted. By analyzing temperature and structural responses of the utility tunnel throughout the fire exposure, the effects on the fire behavior of two different construction methods, cast-in-situ and prefabricated, and of two different materials, ordinary concrete and full lightweight concrete, were explored. The results of the study showed that the shear failure of the cast-in-situ utility tunnel occurred at the end of the top or bottom plate, and the failure of the prefabricated utility tunnel occurred at the junction of the prefabricated member and post-cast concrete. As the temperature increased, the temperature gradient along the thickness direction of the tunnel became apparent. The maximum temperature difference between the inner and outer wall surfaces was 531.7 °C. The highest temperature occurred in the cooling stage after stopping the heating, which provided a reference for the fire protection design and rescue of the utility tunnel. The displacement of the top plate of the prefabricated utility tunnel was 16.8 mm, which was 41.8% larger than that of the cast-in-situ utility tunnel. The bearing capacities of the ordinary concrete utility tunnel and full lightweight concrete utility tunnel after the fire loss were 27% and 16.8%, respectively. The full lightweight concrete utility tunnel exhibited good ductility and fire resistance and high collapse resistance.

关键词： full lightweight concrete construction methods temperature response structural response fire test

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Metabolic hypertension: concept and practice

null

《医学前沿（英文）》 2013年第7卷第2期页码 201-206 doi: 10.1007/s11684-013-0264-4

摘要：

Hypertension is a serious public health problem worldwide. More than 60% of the risk factors for hypertension are associated with metabolic disturbances. Metabolic abnormalities increase the risk for hypertension and cause high blood pressure. Improving metabolic disturbances is beneficial for hypertension treatment. Due to the importance of metabolic abnormalities in the pathogenesis of hypertension, we propose a concept of metabolic hypertension. In this review, we discuss and review the clinical types, pathogenesis, risk evaluation and management of metabolic hypertension. Elucidation of the mechanism of metabolic hypertension should facilitate the design of novel pharmacotherapeutics and dedicated antihypertensive manipulations.

关键词： hypertension cardiometabolic risk factors metabolic abnormalities

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Anensemble method for data stream classification in the presence of concept drift

Omid ABBASZADEH,Ali AMIRI,Ali Reza KHANTEYMOORI

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1059-1068 doi: 10.1631/FITEE.1400398

摘要： One recent area of interest in computer science is data stream management and processing. By ‘data stream’, we refer to continuous and rapidly generated packages of data. Specific features of data streams are immense volume, high production rate, limited data processing time, and data concept drift; these features differentiate the data stream from standard types of data. An issue for the data stream is classification of input data. A novel ensemble classifier is proposed in this paper. The classifier uses base classifiers of two weighting functions under different data input conditions. In addition, a new method is used to determine drift, which emphasizes the precision of the algorithm. Another characteristic of the proposed method is removal of different numbers of the base classifiers based on their quality. Implementation of a weighting mechanism to the base classifiers at the decision-making stage is another advantage of the algorithm. This facilitates adaptability when drifts take place, which leads to classifiers with higher efficiency. Furthermore, the proposed method is tested on a set of standard data and the results confirm higher accuracy compared to available ensemble classifiers and single classifiers. In addition, in some cases the proposed classifier is faster and needs less storage space.

关键词： Data stream Classificaion Ensemble classifiers Concept drift

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基于效用的施工导流方案多目标决策模型

范锡峨,胡志根,刘全

《中国工程科学》 2008年第10卷第7期页码 137-140

摘要：

根据水电工程导流方案的选择与导流建筑物的投资费用、工期、系统风险率及其风险损失之间的关系，提出确定决策者效用函数的方法；运用多目标决策理论建立基于效用的施工导流方案决策模型，对考虑决策者的风险偏好拟定的导流方案集进行优选。实例分析表明，基于效用的施工导流方案多目标决策模型能够反映决策者的风险偏好，按照正隶属度极大原则优选导流方案，使决策者获得最大的满意度。

关键词：施工导流方案效用损失多目标决策模型风险偏好

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Soil health—useful terminology for communication or meaningless concept? Or both?

David S. POWLSON

《农业科学与工程前沿（英文）》 2020年第7卷第3期页码 246-250 doi: 10.15302/J-FASE-2020326

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China’s Agriculture Green Development: from Concept to Actions

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023512

摘要：

● A target-threshold indicator evaluation system is proposed to measure China’s agriculture transformation.

关键词： agricultural transformation Agriculture Green Development historical trend indicator system theoretical conception

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大型公益项目全寿命周期过程集成模型及其支撑条件研究

张国宗,王永华,刘雄

《中国工程科学》 2014年第16卷第10期页码 106-112

摘要：

大型公益项目管理全寿命周期过程集成是指从项目决策、规划设计、实施、运行维护、结束等阶段的项目过程集成。本文以实现项目全寿命周期目标体系为目的，以系统观点、过程观点及价值工程思想为指导，研究了从项目策划、规划设计、实施到运营的全过程集成管理，及其不同阶段不同任务之间的相互关系和作用，建立了大型公益项目全寿命周期过程集成模型，并讨论了大型公益项目全寿命周期过程集成的支撑条件，实现项目全寿命周期的平衡与和谐，提高了项目投资效益和社会公益服务功能，从而提高了大型公益项目的价值。

关键词：大型公益项目全寿命周期过程集成支撑条件

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The main anammox-based processes, the involved microbes and the novel process concept from the application

《环境科学与工程前沿（英文）》 2022年第16卷第7期 doi: 10.1007/s11783-021-1487-1

摘要：

• The PNA, denitratation/anammox, and DAMO/anammox process are reviewed together.

关键词： Anammox Nitritation Denitratation Denitrifying anaerobic methane oxidation Mainstream wastewater

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Control concept and countermeasures for shallow lakes' eutrophication in China

JIN Xiangcan, LU Shaoyong, HU Xiaozhen, JIANG Xia, WU Fengchang

《环境科学与工程前沿（英文）》 2008年第2卷第3期页码 257-266 doi: 10.1007/s11783-008-0063-3

摘要： Research on lake eutrophication in China began in the early 1970s, and many lakes in China are now known to be in meso-eutrophic status. Lake eutrophication has been showing a rapidly increasing trend since 2000. Investigations show that the main reasons for lake eutrophication include a fragile lake background environment, excessive nutrient loading into lakes, excessive human activities, ecological degeneration, weak environmental protection awareness, and lax lake management. Major mechanisms resulting from lake eutrophication include nutrient recycling imbalance, major changes in water chemistry (pH, oxygen, and carbon), lake ecosystem imbalance, and algal prevalence in lakes. Some concepts for controlling eutrophication should be persistently proposed, including lake catchment control, combination of pollutant source control with ecological restoration, protection of three important aspects (terrestrial ecology, lake coast zone, and submerged plant), and combination of lake management with regulation. Measures to control lake eutrophication should include pollution source control (i.e., optimize industrial structural adjustments in the lake catchment, reduce nitrogen and phosphorus emission amounts, and control endogenous pollution) and lake ecological restoration (i.e. establish a zone-lake buffer region and lakeside zone, protect regional vegetation, utilize hydrophytes in renovation technology); countermeasures for lake management should include implementing water quality management, identifying environmental and lake water goals, legislating and formulating laws and regulations to protect lakes, strengthening publicity and the education of people, increasing public awareness through participation in systems and mechanic innovations, establishing lake region management institutions, and ensuring implementation of governance and management measures.

关键词： excessive participation prevalence lakeside Research

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Design concept of the Twin River Bridges in Chongqing, China

Man-Chung TANG

《结构与土木工程前沿（英文）》 2011年第5卷第4期页码 427-431 doi: 10.1007/s11709-011-0134-6

摘要： The Dongshuimen Bridge over the Yangtze River and the Qiansimen Bridge over the Jialing River in Chongqing, China are located at the tip of the Yuzhong Peninsula. Together, they are called the Twin River Bridges. Both are double deck structures carrying four lanes of traffic on their upper decks and two transit tracks on their lower decks. The girders are steel truss structures with orthotropic plates and the towers are made of concrete. Aesthetics were carefully considered for the design of these bridges because of their visibility in the city and their neighboring landmarks.

关键词： long span bridges partially cable-supported girder bridge cable-stayed bridge extradosed steel truss bridge aesthetics Chongqing China

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水产健康养殖理念与发展对策

叶乃好,庄志猛,王清印

《中国工程科学》 2016年第18卷第3期页码 101-104 doi: 10.15302/J-SSCAE-2016.03.017

摘要：

随着水产养殖业规模的扩大和养殖集约化程度逐步提高，人们对产量的片面追求导致养殖环境日趋恶化，病害发生率越来越高，水产品的质量不断下滑，安全问题成为人们关注的焦点。本文从水产健康养殖理念的形成与发展、涉及关键技术问题以及发展趋势等方面探讨了水产健康养殖的重要性和紧迫性，并从科研、技术、产业和政策法规等方面对水产健康养殖的实施和推广提出了一些建议和对策。

关键词：水产健康养殖理念技术

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Utility of transbronchial biopsy in the diagnosis of lymphangioleiomyomatosis

null

《医学前沿（英文）》 2012年第6卷第4期页码 395-405 doi: 10.1007/s11684-012-0231-5

摘要：

Pulmonary lymphangioleiomyomatosis (LAM) is a rare cystic lung disease that targets women during their reproductive years. A confident diagnosis can often be based on clinical grounds, but diagnostic certainty requires pathological analysis. Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease, it is also associated with higher morbidity and mortality than alternative, less invasive techniques. The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM. We conducted two online surveys of over 1 000 LAM patients registered with the LAM Foundation who were accessible by email. Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis. We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM. We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM, obviating the need for surgical lung biopsy in more than half of LAM patients.

关键词： lymphangioleiomyomatosis lymphangiomyomatosis multicystic lung disease diffuse cystic lung disease transbronchial biopsy perivascular epithelioid cell tumor (PEComa) HMB-45