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Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

《结构与土木工程前沿(英文)》 2017年 第11卷 第1期   页码 8-16 doi: 10.1007/s11709-016-0365-7

摘要: Roundabouts are becoming a preferred form of intersection control type due to their safety and capacity benefits. Yield control at roundabout entries inherently reduces fuel consumption and emissions when compared to other conventional intersection types. However, these benefits can be limited by poor driver behavior and judgment when entering the roundabout. This research addresses the nature of gap distributions and use of turn indicators by exiting vehicles at three single-lane roundabouts in Vermont, New York, and Alaska. Presented here is a comparison of vehicle headways measured at two different locations in each roundabout. Rejected headways are analyzed in the context of priority abstaining events when entering drivers yield to vehicles exiting on the same leg of the roundabout suggesting that “true” critical gaps are being overestimated. Results indicate that exiting vehicles, particularly those that do not use their turn indicators when departing from the major-stream of traffic have an influence on the entry decision of drivers on the same approach. This behavior is of particular concern for intersection efficiency (i.e., delay) and sustainability (i.e., excess fuel consumption and emissions). Results prompt the consideration of more consistent guidance on and enforcement of turn indicator use during roundabout negotiations.

关键词: roundabouts     exiting vehicles     turn indicator use     headways    

Experimental investigation and comparative study of inter-turn short-circuits and unbalanced voltage

Fatima BABAA, Abdelmalek KHEZZAR, Mohamed el kamel OUMAAMAR

《能源前沿(英文)》 2013年 第7卷 第3期   页码 271-278 doi: 10.1007/s11708-013-0258-6

摘要: A transient model for an induction machine with stator winding turn faults on a single phase is derived using reference frame transformation theory. The negative sequence component and the 3rd harmonic are often considered as accurate indicators. However, small unbalance in the supply voltage and/or in the machine structure that exists in any real system engenders the same harmonics components. In this case, it is too difficult to distinguish between the current harmonics due to the supply voltage and those originated by inter-turn short-circuit faults. For that, to have the correct diagnosis and to increase the sensitivity and the reliability of the diagnostic system, it is crucial to provide the relationship between the inter-turn short-circuits in the stator winding and the supply voltage imbalance through an accurate mathematical model and via a series of experimental essays.

关键词: induction machines     fault indicator     inter-turn short-circuit fault     unbalance supply voltage    

Machinability of damage-tolerant titanium alloy in orthogonal turn-milling

Tao SUN, Lufang QIN, Junming HOU, Yucan FU

《机械工程前沿(英文)》 2020年 第15卷 第3期   页码 504-515 doi: 10.1007/s11465-020-0586-2

摘要: The damage-tolerant titanium alloy TC21 is used extensively in important parts of advanced aircraft because of its high strength and durability. However, cutting TC21 entails problems, such as high cutting temperature, high tool tip stress, rapid tool wear, and difficulty guaranteeing processing quality. Orthogonal turn-milling can be used to solve these problems. In this study, the machinability of TC21 in orthogonal turn-milling is investigated experimentally to optimize the cutting parameters of orthogonal turn-milling and improve the machining efficiency, tool life, and machining quality of TC21. The mechanism of the effect of turn-milling parameters on tool life is discussed, the relationship between each parameter and tool life is analyzed, and the failure process of a TiAlN-coated tool in turn-milling is explored. Experiments are conducted on the integrity of the machined surface (surface roughness, metallographic structure, and work hardening) by turn-milling, and how the parameters influence such integrity is analyzed. Then, reasonable cutting parameters for TC21 in orthogonal turn-milling are recommended. This study provides strong guidance for exploring the machinability of difficult-to-cut-materials in orthogonal turn-milling and improves the applicability of orthogonal turn-milling for such materials.

关键词: orthogonal turn-milling     damage-tolerant titanium alloy     tool life and failure     machined surface integrity     machinability    

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

《医学前沿(英文)》 2021年 第15卷 第6期   页码 942-942 doi: 10.1007/s11684-021-0876-z

Variable eccentric distance-based tool path generation for orthogonal turn-milling

Fangyu PENG,Wei WANG,Rong YAN,Xianyin DUAN,Bin LI

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 352-366 doi: 10.1007/s11465-015-0361-y

摘要:

This study proposes an algorithm for maximizing strip width in orthogonal turn-milling based on variable eccentric distance. The machining error model is first established based on the local cutting profile at the contact line. The influencing factors of the strip width are then investigated to analyze their features and determine an optimizing strategy. The optimized model for maximum machining strip width is formulated by adopting a variable eccentric distance. Hausdorff distance and Fréchet distance are introduced in this study to implement the constraint function of the machining error in the optimized model. The computing procedure is subsequently provided. Simulations and experiments have been conducted to verify the effectiveness of the proposed algorithm.

关键词: orthogonal turn-milling     variable eccentric distance     local cutting profile     machining strip-width maximization    

A novel flavonol-based colorimetric and turn-on fluorescent probe for rapid determination of hydrazine

《化学科学与工程前沿(英文)》 2023年 第17卷 第1期   页码 24-33 doi: 10.1007/s11705-022-2171-1

摘要: Hydrazine is extremely toxic and causes severe harm to human body. Herein, a novel fluorescent probe 4-oxo-2-styryl-4H-chromen-3-yl thiophene-2-carboxylate (FHT) was synthesized for detecting hydrazine by using natural cinnamaldehyde as starting material. This probe exhibited significantly enhanced fluorescence response towards hydrazine over various common metal ions, anions, and amine compounds. The detection limit of probe FHT for hydrazine was as low as 0.14 μmol·L–1, significantly lower than that of the threshold value of 0.312 μmol·L–1, imposed by the Environmental Protection Agency. Moreover, the proposed probe was able to detect hydrazine within wide pH (5–10) and linear detection ranges (0–110 μmol·L–1). This probe was employed for determining trace hydrazine in different environmental water samples. The probe FHT-loaded filter paper strips were able to conveniently detect hydrazine of low concentration through distinct naked-eye and fluorescent color changes. Importantly, the probe FHT with low cytotoxicity was successfully applied to visualize hydrazine in living Hela cells and zebrafish.

关键词: cinnamaldehyde     3-hydroxychromone derivative     hydrazine     fluorescent probe    

Screening of indicator pharmaceuticals and personal care products in landfill leachates: a case study

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1716-y

摘要:

● A systematic framework was developed to identify i-PPCPs for landfill leachate.

关键词: Landfill leachates     PPCPs     Indicator     Screening criteria     Source-specificity    

Modeling effects of a tidal barrage on water quality indicator distribution in the Severn Estuary

Guanghai GAO, Roger A. FALCONER, Binliang LIN

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 211-218 doi: 10.1007/s11783-012-0464-1

摘要: In this study, emphasis has focused on assessing the potential hydro-environmental impacts of a barrage across the Severn Estuary, with a numerical model being developed and applied to the estuary to assess the impacts of proposed Severn Barrage on the hydrodynamic, sediment transport and faecal indicator organism distribution within the estuary. The results show that the Severn Barrage has the potential to reduce the tidal currents in a highly dynamic estuary. This leads to the reduction of suspended sediment concentrations, which in turn affects the bacterial transport processes which is highly related to the sediment transport processes.

关键词: water quality indicator     Severn Estuary     numerical model     tidal energy    

Water environment security indicator system for urban water management

Tian HAO, Pengfei DU, Yun GAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 678-691 doi: 10.1007/s11783-012-0450-7

摘要: Water environment security (WES) is defined in terms of three aspects: first, that it meets basic demands due to industrial and domestic usage; second, that it protects public health from acute and chronic threats; and third, that measures are adopted to ensure sustainable ecological functioning of freshwater resources. Limitations associated with current water environment security indicators in China — including inefficiency in terms of environmental monitoring, inappropriate indicators and parameters that do not take sufficient account of local water characteristics, and a lack of management targets — leads to a failure of effective water management. To achieve better water environment management, a systematic approach, encompassing several steps including establish ideal indicator system and narrow down the scope, screen priority pollutants, identify local characteristics and organize discussion workshop, should be followed to establish a comprehensive water environment indicator system. A case study in Suzhou is included to demonstrate the detailed operational procedures used to assess the risks associated with poor management practices relating to water environment security as well as design an appropriate water environment security indicator system.

关键词: water environment security     supervision and management     monitoring parameter     indicator system     Suzhou    

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    

Antimicrobial use in food animal production: situation analysis and contributing factors

Ziping WU

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 301-311 doi: 10.15302/J-FASE-2018207

摘要:

By measuring the quantity and ways in which antimicrobials are used, and reviewing different technical and socioeconomic factors influencing antimicrobial use at farm level, this study discusses the main knowledge gaps in antimicrobial use in food animal production and provides recommendations for future research and policy development. The review reveals that antimicrobial use in food animals exhibit strong regional and species differences, and there are still large information gaps concerning the current state of antimicrobial use. Factors associated with animal health (including antimicrobial resistance), animal health improvement, economic costs and benefits relevant to animal diseases, and potential technological alternatives or alternative systems all have an impact on antimicrobial use on the farm. There is a clear need to resolve the data gap by monitoring antimicrobial use and developing an analytical framework to better understand farmer behaviors under different technical, economic and environmental circumstances.

关键词: antimicrobial use     drivers for antimicrobial use     food animal production    

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

null

《医学前沿(英文)》 2016年 第10卷 第1期   页码 41-51 doi: 10.1007/s11684-016-0429-z

摘要:

Midline2 (MID2) is an ubiquitin-conjugating E2 enzyme linked to tumor progression and a novel interacting partner of breast cancer 1, early-onset (BRCA1). However, the role of MID2 in breast cancer remains unknown. This study investigated the expression, prognostic value, and role of MID2 in breast cancer. The expression of MID2 mRNA and protein was significantly upregulated in breast cancer tissue and established cell lines compared with that in normal breast epithelial cells and paired adjacent non-tumor tissue (P<0.001). Immunohistochemical analysis demonstrated that MID2 was overexpressed in 272 of 284 (95.8%) paraffin-embedded, archived breast cancer tissue. Moreover, MID2 expression increased with advanced clinical stage (P<0.001). High MID2 expression was significantly associated with advanced clinical stages and T, N, and M staging (all P<0.05). Univariate and multivariate analyses indicated that high MID2 expression was an independent prognostic factor for poor overall survival in the entire cohort (93.73 vs. 172.1 months; P<0.001, log-rank test) and in subgroups with stages Tis+ I+ II and III+ IV. Furthermore, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide colony formation, and anchorage-independent growth ability assays were conducted. Results showed that siRNA silencing of MID2 expression significantly reduced MCF-7 and MDA-MB-231 cell proliferation in vitro and blocked the growth of MDA-MB-231 cell xenograft tumors in vivo (P<0.05). This study indicated that MID2 may be a novel prognostic marker and interventional target in breast cancer.

关键词: breast cancer     MID2     proliferation     overall survival     xenograft    

Moving policy and regulation forward for single-use plastic alternatives

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1423-5

摘要: Single-use plastics are often used once or cannot be reused for extended periods. They are widely consumed with the rapid development of social economy. The waste generated by single-use plastics threatens ecosystem health by entering the environment and ultimately restricts sustainable human development. The innovation of sustainable and environmentally friendly single-use plastic alternative materials and the joint participation of governments, enterprises and the public are promising technologies and management approaches that can solve the problem of single-use plastics wastes. The development of single-use plastic alternative products can be promoted fundamentally only by improving relevant legislation and standards, providing differentiated industrial policies, encouraging scientific and technological innovation and expanding public participation.

关键词: Single-use plastic alternatives     Policy     Regulation     Sustainable development    

Nudging sustainable consumption of residential energy use: A behavioral economics perspective

《工程管理前沿(英文)》   页码 540-545 doi: 10.1007/s42524-023-0264-2

摘要: Nudging sustainable consumption of residential energy use: A behavioral economics perspective

关键词: consumption energy use    

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

《农业科学与工程前沿(英文)》 2015年 第2卷 第2期   页码 115-123 doi: 10.15302/J-FASE-2015055

摘要: This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

关键词: rice     nitrogen-efficient cultivar     grain fill     harvest index     nitrogen use efficiency     water use efficiency    

标题 作者 时间 类型 操作

Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

期刊论文

Experimental investigation and comparative study of inter-turn short-circuits and unbalanced voltage

Fatima BABAA, Abdelmalek KHEZZAR, Mohamed el kamel OUMAAMAR

期刊论文

Machinability of damage-tolerant titanium alloy in orthogonal turn-milling

Tao SUN, Lufang QIN, Junming HOU, Yucan FU

期刊论文

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

期刊论文

Variable eccentric distance-based tool path generation for orthogonal turn-milling

Fangyu PENG,Wei WANG,Rong YAN,Xianyin DUAN,Bin LI

期刊论文

A novel flavonol-based colorimetric and turn-on fluorescent probe for rapid determination of hydrazine

期刊论文

Screening of indicator pharmaceuticals and personal care products in landfill leachates: a case study

期刊论文

Modeling effects of a tidal barrage on water quality indicator distribution in the Severn Estuary

Guanghai GAO, Roger A. FALCONER, Binliang LIN

期刊论文

Water environment security indicator system for urban water management

Tian HAO, Pengfei DU, Yun GAO

期刊论文

China’s Agriculture Green Development: from Concept to Actions

期刊论文

Antimicrobial use in food animal production: situation analysis and contributing factors

Ziping WU

期刊论文

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

null

期刊论文

Moving policy and regulation forward for single-use plastic alternatives

期刊论文

Nudging sustainable consumption of residential energy use: A behavioral economics perspective

期刊论文

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

期刊论文