Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 97

年份

2024 1

2023 8

2022 3

2021 8

2020 5

2019 8

2018 7

2017 6

2016 5

2015 5

2014 4

2013 4

2012 2

2011 3

2010 6

2009 7

2008 5

2007 4

2005 1

2004 1

展开︾

关键词

横沙东滩 3

长江口 3

&gamma 1

CCK-8 实验 1

HY-2 卫星地面应用系统 1

IP语音 1

MERS-CoV 1

MTT 实验 1

REITs 型公共租赁住房 1

上海国际航运中心 1

上行非正交多址；Generalized Welch界等式；多级接收功率；序列分组 1

业务运行模型 1

中小企业 1

中药 1

云制造 1

互联网 1

任务调度 1

仿生合成 1

住房特征 1

展开︾

检索范围：

排序：展示方式：

Plasmonic Au nanoparticles supported on both sides of TiO2 hollow spheres for maximising photocatalytic activity under visible light

Jianwei Lu, Lan Lan, Xiaoteng Terence Liu, Na Wang, Xiaolei Fan

《化学科学与工程前沿（英文）》 2019年第13卷第4期页码 665-671 doi: 10.1007/s11705-019-1815-2

摘要： A strategy of intensifying the visible light harvesting ability of anatase TiO hollow spheres (HSs) was developed, in which both sides of TiO HSs were utilised for stabilising Au nanoparticles (NPs) through the sacrificial templating method and convex surface-induced confinement. The composite structure of single Au NP yolk-TiO shell-Au NPs, denoted as Au@Au(TiO , was rendered and confirmed by the transmission electron microscopy analysis. Au@Au(TiO showed enhanced photocatalytic activity in the degradation of methylene blue and phenol in aqueous phase under visible light surpassing that of other reference materials such as Au(TiO by 77% and Au@P25 by 52%, respectively, in phenol degradation.

关键词： TiO₂ hollow spheres plasmonic Au nanoparticles confinement visible light photocatalytic degradation

HTML PDF 收藏

Governance approach to China’s environmental challenges: Towards a theoretical synthesis

QI Ye, XUE Lan, ZHANG Lingyun

《环境科学与工程前沿（英文）》 2007年第1卷第4期页码 385-400 doi: 10.1007/s11783-007-0066-5

摘要： This paper reviewed recent research in environmental governance as a response to environmental challenges at various spatial, temporal and administrative scales. It documented the shift of approach from regulation to governance, and attempted to provide a comprehensive understanding why and how the transformation occurred. It also described major factors and forces of environmental governance, and discussed research advance in environmental governance theory. Finally, this paper summarized recent research findings on environmental governance in China, and listed policy recommendation for enhancing the governance.

关键词： environmental governance approach temporal regulation various

HTML PDF 收藏

A rain-on-snow mixed flood forecast model and its application

Jian WU, Lan LI,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 440-444 doi: 10.1007/s11709-009-0051-0

摘要： Based on summarizing the rule of rainstorm and snowmelt mixed flood, the structure of rain-on-snow runoff-generation is discussed; and critical temperature is used to determine the form of precipitation and snowmelt factor, taking into account rainfall volume of snowmelt. A rain-on-snow flood forecast model is developed by combining LL-Ⅰdistributed hydrology model. The Kalangguer River, an internal river in Xinjiang Autonomous Region, is taken for example. It is indicated that the model has a higher precision of forecasting; its determinacy coefficient is greater than 0.80.

关键词： Xinjiang Autonomous forecasting hydrology temperature rain-on-snow runoff-generation

HTML PDF 收藏

High risk factors for pulmonary fungous infection in intensive care units of neurosurgery

ZHU Wenyu, TAN Liping, CHEN Xiangfeng, HUANG Qiang, LAN Qing

《医学前沿（英文）》 2007年第1卷第3期页码 299-303 doi: 10.1007/s11684-007-0057-8

摘要： By analyzing the high risk factors for pulmonary fungous infection in intensive care units of neurosurgery, the strategy of early diagnosis and treatment was explored. According to the domestic diagnostic standard on pulmonary fungous infection, clinical data on 58 patients with the infection in our department were analyzed. One hundred and seventeen strains of fungi were separated from the 58 cases. Candidiasis was the most frequent type, accounting for 92.3% of the cases. Conditions such as the severity of primary diseases, long-time coma, long-term use of broad-spectrum antibiotic, abuse of glucocorticoid, the open airway, and some invasive intubations, may be regarded as high risk factors for pulmonary fungous infection. Fluconazole showed good clinical effects on the treatment of fungous infection. To eliminate these high risk factors, early diagnosis and the use of prophylactic antifungal agents can help reduce the incidence of pulmonary fungous infection.

关键词： seventeen incidence glucocorticoid broad-spectrum antibiotic Candidiasis

HTML PDF 收藏

Thermal transport in organic/inorganic composites

Bin LIU, Lan DONG, Qing XI, Xiangfan XU, Jun ZHOU, Baowen LI

《能源前沿（英文）》 2018年第12卷第1期页码 72-86 doi: 10.1007/s11708-018-0526-6

摘要： Composite materials, which consist of organic and inorganic components, are widely used in various fields because of their excellent mechanical properties, resistance to corrosion, low-cost fabrication, etc. Thermal properties of organic/inorganic composites play a crucial role in some applications such as thermal interface materials for micro-electronic packaging, nano-porous materials for sensor development, thermal insulators for aerospace, and high-performance thermoelectric materials for power generation and refrigeration. In the past few years, many studies have been conducted to reveal the physical mechanism of thermal transport in organic/inorganic composite materials in order to stimulate their practical applications. In this paper, the theoretical and experimental progresses in this field are reviewed. Besides, main factors affecting the thermal conductivity of organic/inorganic composites are discussed, including the intrinsic properties of organic matrix and inorganic fillers, topological structure of composites, loading volume fraction, and the interfacial thermal resistance between fillers and organic matrix.

关键词： thermal conductivity organic/inorganic composites effective medium theory thermal percolation theory interfacial thermal resistance

HTML PDF 收藏

Nanocrystal technology for drug formulation and delivery

Tzu-Lan CHANG, Honglei ZHAN, Danni LIANG, Jun F. LIANG

《化学科学与工程前沿（英文）》 2015年第9卷第1期页码 1-14 doi: 10.1007/s11705-015-1509-3

摘要： With the development of modern technology like high throughput screening, combinatorial chemistry and computer aid drug design, the drug discovery process has been dramatically accelerated. However, new drug candidates often exhibit poor aqueous or even organic medium solubility. Additionally, many of them may have low dissolution velocity and low oral bioavailability. Nanocrystal formulation sheds new light on advanced drug development. Due to small (nano- or micro- meters) sizes, the increased surface-volume ratio leads to dramatically enhanced drug dissolution velocity and saturation solubility. The simplicity in preparation and the potential for various administration routes allow drug nanocrystals to be a novel drug delivery system for specific diseases (i.e. cancer). In addition to the comprehensive review of different technologies and methods in drug nanocrystal preparation, suspension, and stabilization, we will also compare nano- and micro-sized drug crystals in pharmaceutical applications and discuss current nanocrystal drugs on the market and their limitations.

关键词： drug nanocrystal nanotechnology formulation bioavailability stabilizers drug delivery

HTML PDF 收藏

Effect of UAV prewetting application during the flowering period of cotton on pesticide droplet deposition

Weixiang YAO, Xianju WANG, Yubin LAN, Ji JIN

《农业科学与工程前沿（英文）》 2018年第5卷第4期页码 455-461 doi: 10.15302/J-FASE-2018232

摘要：

Prewetting process can reduce the contact angle between the droplet and the leaf blade, so that the droplet can more easily wet and spread, thereby increasing the quantity of deposition. To improve the effectiveness of pesticides on cotton leaves, prewetting by single-rotor electric unmanned aerial vehicles (UAV) was studied, focusing on the effects of pesticide deposition on cotton leaves during the flowering period. Cotton leaves in 0°–30°, 30°–60°, 60°–90° leaf blade angle ranges (angle between the leaf blade and the horizontal plane) were examined. In the first experiment, four different prewetting volumes (0, 1.6, 3.2 and 4.8 L) were sprayed by a single-rotor electric UAV on four cotton plots (plots A to D) each with an area of 120 m , and then each area was sprayed with a 0.8% (w/v) ponceau 2R solution by another single-rotor electric UAV. The results revealed that with no prewetting, droplet deposition quantity decreased with increasing leaf blade inclination. After prewetting, the mean droplet deposition quantity on plots B, C and D increased by 39.8%, 9.7% and 24.9%, respectively. The prewetting rate of 1.6 L per 120 m had the most significant effect on improving the deposition of droplets. It was also found that the mean droplet deposition quantity in each leaf blade angle range increased after prewetting. For the leaf blade angle range 60° to 90°, this increase was the most pronounced, with 0.043, 0.062, 0.057 and 0.048 L·cm in plots A–D, respectively. Also, droplet deposition uniformity in the leaf blade angle range 60°–90° was better after prewetting. These results should provide a valuable reference for future research and practice to improve the effectiveness of pesticides applied to cotton by aerial applications.

关键词： aerial spray cotton deposition flowering period leaf angle prewetting UAV

HTML PDF 收藏

Ag/PMMA hollow waveguide for solar energy transmission

He LAN, Jianjun HAN, Hongping CHEN, Xiujian ZHAO

《化学科学与工程前沿（英文）》 2011年第5卷第3期页码 303-307 doi: 10.1007/s11705-010-0565-y

摘要： This paper describes an elaborate study on obtaining Ag/PMMA (polymethyl methacrylate) leaky hollow waveguide which has a large aperture and low loss in transmitting solar energy. Through analyses and comparison, a quartz capillary with the inner diameter of 2 mm was chosen as hollow waveguide. We used the xenon light source, which has the similar spectrum as the sunlight to test and analyze the performance of the Ag/PMMA leakage hollow waveguide. The results are consistent with the transmitted theory of the dielectric/metal leaky type well. Meanwhile, the Ag/PMMA leaky-type hollow waveguide in this work had good qualities. Therefore, it will be a satisfactory medium for solar energy transmission.

关键词： hollow waveguide transmit the solar energy Ag/PMMA multiple film parabolic collector

HTML PDF 收藏

Trajectory optimization with constraints for alpine skiers based on multi-phase nonlinear optimal control

Cong-ying Cai, Xiao-lan Yao,yaoxiaolan@bit.edu.cn

《信息与电子工程前沿（英文）》 2020年第21卷第10期页码 1413-1534 doi: 10.1631/FITEE.1900586

摘要： The super giant slalom (Super-G) is a speed event in alpine skiing, in which the skier trajectory has a significant influence on the athletes’ performances. It is a challenging task to determine an for the skiers along the entire course because of the complexity and difficulty in the convergence of the optimization model. In this study, a model for alpine skiers competing in the Super-G is established based on the theory, in which the objective is to minimize the runtime between the starting point and the finish line. The original problem is converted into a multi-phase nonlinear problem solved with a , and the trajectory parameters are optimized to discover the time-. Using carried out by the MATLAB optimization toolbox, the is obtained under several equality and inequality constraints. Simulation results reveal the effectiveness and rationality of the model. A test is carried out to show that our code works properly. In addition, several practical proposals are provided to help alpine skiers improve their training and skiing performance.

HTML PDF 收藏

无线局域网上IP语音传输的容量分析

陈立全,胡爱群,周雪莉

《中国工程科学》 2005年第7卷第7期页码 81-85

摘要：

由于无线媒介的易变性，IP语音在无线局域网上传输受到极大的限制。通过对无线局域网媒体接入层机制的分析，考虑了碰撞概率因素，提出了采用马尔可夫链模型来推导在IEEE 80211b/a/g标准下单个接入点同时支持IP语音用户最大容量的方法，计算出针对不同IP语音编码标准如G711，G729和G723.1下的用户容量上限。并在NS2仿真环境下进行结果验证。

关键词：无线局域网 IP语音容量马尔可夫链

HTML PDF 收藏

Effects of baffles on separation of aqueous ethanol solution with hollow fibers

Zhihong YANG, Guoliang ZHANG, Lan LIN, Danping REN, Qin MENG, Hongzi ZHANG

《化学科学与工程前沿（英文）》 2009年第3卷第1期页码 68-72 doi: 10.1007/s11705-009-0130-8

摘要： The effects of baffles on the operation and mass-transfer characteristics in novel hollow fiber membrane contactor used in distillation were investigated. Hollow fiber membranes, coated with a 7 μm polydimethyl-siloxane, were operated as structural packing in the separation of ethanol-water solutions. The parallel flow mode was chosen for separation due to the stronger driving force of the concentration difference, in which liquid flows through the lumens of the fibers and vapor flows countercurrent-wise outside the fibers. Two baffles were installed on the shell side of the membrane contactors to enhance separation, which had a round shape with a semi-lunar hole. The results show that both baffled and unbaffled membrane contactors gave better, more productive separations than traditional packing in distillation, such as the excellent Sulzer Gauze BX structured packing. The baffled membrane contactors performed better than unbaffled ones, especially at high vapor velocities. The minimal HTU of membrane contactor with baffles could reach as low as 4.5 cm, and almost all the contactors could work well above the limit where flooding normally occurs in conventional cases. Theoretical analysis predicted that baffles helped membrane module to obtain a higher mass-transfer coefficient and a smaller mass-transfer resistance. Finally, theoretical mass-transfer coefficient and experimental value were compared as well as the contribution of each individual mass-transfer coefficients among liquid, gas and membrane.

关键词： hollow fiber membrane contactor baffle mass-transfer ethanol-water

HTML PDF 收藏

Expression of PC-cell-derived growth factor in breast cancer

Haiping SONG MD, Lan SHI MD, Chunping LIU MD, Tao HUANG MD,

《医学前沿（英文）》 2009年第3卷第4期页码 426-430 doi: 10.1007/s11684-009-0085-7

摘要： This study is mainly aimed at evaluating the expression of PC-cell-derived growth factor (PCDGF) in breast cancer and breast adenofibroma, and to compare with other commonly used clinical pathological indices, then to investigate the diagnostic and targeted therapeutic purpose of PCDGF in breast cancer tissue. In this study, we detected the expression of PCDGF, p53 and CerbB-2 in breast cancer tissue and the expression of PCDGF in breast adenofibroma tissue by immunohistochemical method, and analyzed the relationship between them. We found that PCDGF was expressed in most breast cancer tissue, but was not in breast adenofibroma tissue, and the expression of PCDGF was related with the tumor’s pathological category and the expression of estrogen receptor (ER) and progesterone receptor (PR) and p53, but there was no statistical dependability between PCDGF and cerbB-2. From this study, we predict that PCDGF may serve as a marker in the secondary diagnosis of breast cancer, and may participate in the generation and differentiation of breast cancer cells, and become an effective target of therapy for breast cancer.

关键词： PC-cell-derived growth factor breast neoplasms clinical markers

HTML PDF 收藏

Comparing the adsorption behaviors of Cd, Cu and Pb from water onto Fe-Mn binary oxide, MnO

Wei XU,Huachun LAN,Hongjie WANG,Hongming LIU,Jiuhui QU

《环境科学与工程前沿（英文）》 2015年第9卷第3期页码 385-393 doi: 10.1007/s11783-014-0648-y

摘要： The adsorption potential of FMBO, FeOOH, MnO for the removal of Cd , Cu and Pb in aqueous systems was investigated in this study. Comparing to FMBO and FeOOH, MnO offered a much higher removal capacity towards the three metal ions. The maximal adsorption capacity of MnO for Cd , Cu and Pb were 1.23, 2.25 and 2.60 mmol·g , respectively. And that for FMBO were 0.37, 1.13, and 1.18 mmol·g and for FeOOH were 0.11, 0.86 and 0.48 mmol·g , respectively. The adsorption behaviors of the three metal ions on the three adsorbents were all significantly affected by pH values and heavy metal removal efficiency increased with pH increased. The Langmuir and Freundlich adsorption models were used to describe the adsorption equilibrium of the three metal ions onto the three adsorbents. Results showed that the adsorption equilibrium data fitted well to Langmuir isotherm and this indicated that adsorption of metal ions occurred on the three metal oxides adsorbents limited to the formation of a monolayer. More negative charged of MnO surface than that of FMBO and FeOOH could be ascribed by lower pH of MnO than that of FMBO and FeOOH and this could contribute to more binding sites on MnO surface than that of FMBO and FeOOH. The higher metal ions uptake by MnO than FMBO and FeOOH could be well explained by the surface charge mechanism.

关键词： heavy metals Fe-Mn binary oxide manganese dioxide ferric hydroxide adsorption

HTML PDF 收藏

Research on Multidimensional Connotations of Megaproject Construction Organization Citizenship Behavior

Qing-hua He,De-lei Yang,Yong-kui Li,Lan Luo

《工程管理前沿（英文）》 2015年第2卷第2期页码 148-153 doi: 10.15302/J-FEM-2015024

摘要： Based on a literature review and the context characteristics of construction megaprojects (CMPs), a multidimensional connotation model of CMP citizenship behavior was proposed, including definitions, actors, and dimensions. Organizational citizenship behavior includes Cooperation Behavior (CoB), Collaboration Behavior (ClB), Innovation Behavior (IB), Voice Behavior (VB),Conscientiousness & Dedication Behavior (CDB), Benefit Defense Behavior (BDB) and Guanxi (Relations) Maintenance Behavior (GMB). Actors were divided into three levels that were project managers (individual), participant agents (group) and project organization (network).

关键词： construction megaproject (CMP) organizational citizenship behavior connotation grounded theory

HTML PDF 收藏

Dynamic Target Tracking of Unmanned Aerial Vehicles Under Unpredictable Disturbances

Yanjie Chen,Yangning Wu,Limin Lan,Hang Zhong,Zhiqiang Miao,Hui Zhang,Yaonan Wang,

《工程（英文）》 doi: 10.1016/j.eng.2023.05.017

摘要： This study proposes an image-based visual servoing (IBVS) method based on a velocity observer for an unmanned aerial vehicle (UAV) for tracking a dynamic target in Global Positioning System (GPS)-denied environments. The proposed method derives the simplified and decoupled image dynamics of underactuated UAVs using a constructed virtual camera and then considers the uncertainties caused by the unpredictable rotations and velocities of the dynamic target. A novel image depth model that extends the IBVS method to track a rotating target with arbitrary orientations is proposed. The depth model ensures image feature accuracy and image trajectory smoothness in rotating target tracking. The relative velocities of the UAV and the dynamic target are estimated using the proposed velocity observer. Thanks to the velocity observer, translational velocity measurements are not required, and the control chatter caused by noise-containing measurements is mitigated. An integral-based filter is proposed to compensate for unpredictable environmental disturbances in order to improve the anti-disturbance ability. The stability of the velocity observer and IBVS controller is analyzed using the Lyapunov method. Comparative simulations and multistage experiments are conducted to illustrate the tracking stability, anti-disturbance ability, and tracking robustness of the proposed method with a dynamic rotating target.

关键词： Unmanned aerial vehicle Visual servoing Velocity observer Target tracking