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2023全球十大工程成就 2

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Applying the multi-zone model in predicting the operating range of HCCI engines

Ming JIA, Maozhao XIE, Zhijun PENG,

《能源前沿（英文）》 2010年第4卷第3期页码 414-423 doi: 10.1007/s11708-010-0108-8

摘要： In this paper, a multi-zone model is developed to predict the operating range of homogeneous charge compression ignition (HCCI) engines. The boundaries of the operating range were determined by knock (presented by ringing intensity), partial burn (presented by combustion efficiency), and cycle-to-cycle variations (presented by the sensitivity of indicated mean effective pressure to initial temperature). By simulating an HCCI engine fueled with iso-octane, the knock and cycle-to-cycle variations predicted by the model showed satisfactory agreement with measurements made under different initial temperatures and equivalence ratios; the operating range was also well reproduced by the model. Furthermore, the model was applied to predict the operating range of the HCCI engine under different engine speeds by varying the intake temperatures and equivalence ratios. The potential to extend the operating range of the HCCI engine through two strategies, i.e., variable compression ratio and intake pressure boosting, was then investigated. Results indicate that the ignition point can be efficiently controlled by varying the compression ratio. A low load range can be extended by increasing the intake temperature while reducing the compression ratio. Higher intake temperatures and lower compression ratios can also extend the high load range. Boosting intake pressure is helpful in controlling the combustion of the HCCI engine, resulting in an extended high load range.

关键词： homogeneous charge compression ignition (HCCI) engine multi-zone operating range

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Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

Jie LIU, Fan CHEN, Haiqing GENG, Xinxin QIU, Binbin CAI,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 349-360 doi: 10.1007/s11783-010-0027-2

摘要： The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.

关键词： range of impact quantitative analysis highway construction Longitudinal Range-Gorge Region

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导航卫星双向伪距时间同步

谭述森

《中国工程科学》 2006年第8卷第12期页码 70-74

摘要：

针对卫星导航系统时间同步需求，提出了导航卫星双向伪距时间同步的理论根据，并就4种基本同步方法（双向无线电伪距同步方法, 星地双向激光伪距同步方法,双向卫星中继无线电伪距同步方法, 双向地球站中继无线电伪距同步方法）与应用进行了分析，与目前国际导航卫星时间同步通用方法相比,具有精度高, 方法简单，设备负担轻特点。

关键词：导航卫星伪距时间同步

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Identification of abnormal operating conditions and intelligent decision system

Xiuliang LI, Junjie JIANG, Hongye SU, Jian CHU

《机械工程前沿（英文）》 2011年第6卷第4期页码 456-462 doi: 10.1007/s11465-011-0224-0

摘要：

In earth pressure balance (EPB) shield construction, the “plastic flow state” is difficult to form using the soil dug in the capsule because it can cause three abnormal operating conditions, including occlusion, caking in the capsule, and spewing at the outlet of the dump device. These abnormal operating conditions can, in turn, trigger failure in tunneling, cutter-device damage, and even catastrophic incidents, such as ground settlement. This present paper effectively integrates the mechanism of abnormal operating conditions and knowledge of soil conditioning, and establishes a uniform model of identifying abnormal conditions and intelligent decision support system based on the belief rule-base system. The model maximizes knowledge in improving the soil, construction experience, and data to optimize the model online. Finally, a numerical simulation with specific construction data is presented to illustrate the effectiveness of the algorithm.

关键词： earth pressure balance (EPB) shield machine soil pressure cabin abnormal operating condition belief rule-base system

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Accelerated degradation of orange G over a widepH range in the presence of FeVO

Xiaoxia Ou, Jianfang Yan, Fengjie Zhang, Chunhua Zhang

《环境科学与工程前沿（英文）》 2018年第12卷第1期 doi: 10.1007/s11783-018-1013-3

摘要： In this study, FeVO was prepared andused as Fenton-like catalyst to degrade orange G (OG) dye. The removalof OG in an aqueous solution containing 0.5 g·L FeVO and 15 mmol·L hydrogen peroxide at pH 7.0 reached 93.2%. Similar rates were achievedat pH 5.7 ( = 0.0471 min ), pH 7.0 ( = 0.0438 min ), and pH 7.7 ( = 0.0434 min ). The FeVO catalyst successfullyovercomes the problem faced in the heterogeneous Fenton process, i.e.,the narrow working pH range. The data for the removal of OG in FeVO systems containing H O conform to the Langmuir–Hinshelwood model ( = 0.9988),indicating that adsorption and surface reaction are the two basicmechanisms for OG removal in the FeVO –H O system. Furthermore, the irradiationof FeVO by visible light significantly increasesthe degradation rate of OG, which is attributed to the enhanced ratesof the iron cycles and vanadium cycles.

关键词： Azo dye Degradation FeVO₄ Kinetics Advanced oxidation processes

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Experimental study on influence of operating parameters on tar components from corn straw gasification

Shuai GUO, Xiao WEI, Deyong CHE, Hongpeng LIU, Baizhong SUN

《能源前沿（英文）》 2021年第15卷第2期页码 374-383 doi: 10.1007/s11708-020-0710-3

摘要： Gasification is a promising approach for converting solid fuel sources, including renewable ones like biomass, for use. The main problem in biomass gasification is the formation of condensable tars, including polycyclic aromatic hydrocarbons (PAHs). This paper investigated the conversion of tar components during corn straw gasification. It analyzed collected tar components using a gas chromatograph-mass spectrograph (GC-MS). Experimental results indicate that, with increasing temperature from 700°C to 900°C, the concentrations of benzene, indene, phenanthrene, naphthalene, acenaphthylene, fluorene, and pyrene increased whereas those of toluene, phenol, 1-methylnaphthalene, and 2-methylnaphthalene decreased. As the equivalence ratio (ER) increased from 0.21 to 0.34, the concentrations of indene and phenanthrene increased from 0.148% and 0.087% to 0.232% and 0.223%, respectively. Further, the phenol content increased as ER increased from 0.21 to 0.26 and then decreased as the ER increased further to 0.34. Other parameters like the steam/biomass (S/B) ratio and catalyst also played a critical role in tar reduction. This paper demonstrates the conversion of some tar components and elucidates their chemical properties during gasification.

关键词： gasification tar components operating parameters

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Prevention of surgical site infection under different ventilation systems in operating room environment

Zhijian Liu, Haiyang Liu, Hang Yin, Rui Rong, Guoqing Cao, Qihong Deng

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-020-1327-9

摘要： Abstract • The effectiveness of four different ventilation systems was compared in depth. • Airflow and bacteria-carrying particles concentration were quantitatively analyzed. • Vertical laminar airflow with high airflow rate could not achieve desired effect. • Temperature-controlled airflow ventilation could guarantee air cleanliness. Biological particles in the operating room (OR) air environment can cause surgical site infections (SSIs). Various ventilation systems have been employed in ORs to ensure an ultraclean environment. However, the effect of different ventilation systems on the control of bacteria-carrying particles (BCPs) released from the surgical staff during surgery is unclear. In this study, the performance of four different ventilation systems (vertical laminar airflow ventilation (VLAF), horizontal laminar airflow ventilation (HLAF), differential vertical airflow ventilation (DVAF), and temperature-controlled airflow ventilation (TAF)) used in an OR was evaluated and compared based on the spatial BCP concentration. The airflow field in the OR was solved by the Renormalization Group (RNG) k-e turbulence model, and the BCP phase was calculated by Lagrangian particle tracking (LPT) and the discrete random walk (DRW) model. It was found that the TAF system was the most effective ventilation system among the four ventilation systems for ensuring air cleanliness in the operating area. This study also indicated that air cleanliness in the operating area depended not only on the airflow rate of the ventilation system but also on the airflow distribution, which was greatly affected by obstacles such as surgical lamps and surgical staff.

关键词： Operating room (OR) Bacteria-carrying particles (BCPs) Surgical site infections (SSIs) Ventilation

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Kd-tree and quad-tree decompositions for declustering of 2D range queries over uncertain space

Ahmet SAYAR,Süleyman EKEN,Okan ÖZTÜRK

《信息与电子工程前沿（英文）》 2015年第16卷第2期页码 98-108 doi: 10.1631/FITEE.1400165

摘要： We present a study to show the possibility of using two well-known space partitioning and indexing techniques, kd trees and quad trees, in declustering applications to increase input/output (I/O) parallelization and reduce spatial data processing times. This parallelization enables time-consuming computational geometry algorithms to be applied efficiently to big spatial data rendering and querying. The key challenge is how to balance the spatial processing load across a large number of worker nodes, given significant performance heterogeneity in nodes and processing skews in the workload.

关键词： Kd tree Quad tree Space partitioning Spatial indexing Range queries Query optimization

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Effects of operating conditions on membrane charge property and nanofiltration

Li XU, Li-Shun DU, Jing HE

《化学科学与工程前沿（英文）》 2011年第5卷第4期页码 492-499 doi: 10.1007/s11705-011-1143-7

摘要： The effects of the operating pressure, cross flow velocity, feed concentration, and temperature on the streaming and Zeta potential of the membranes were studied. The permeate flux and the retention rate under different nanofiltration operating conditions were also investigated. The results show that the higher pressure, feed concentration, temperature, and lower cross flow velocity lead to the higher absolute value of streaming and Zeta potential. The permeate flux of the nanofiltration decreases with the feed concentration and increases with not only the pressure but also the cross flow velocity and temperature. The higher the pressure and the cross flow velocity, the higher the retention rate. The lower feed concentration and higher temperature leads to lower retention rate. The effects of the operating conditions on the permeate flux and the retention rate were explained by the variation of the membrane charge property.

关键词： nanofiltration membrane streaming potential Zeta potential permeate flux retention rate

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Intelligent technologies help operating mobile cabin hospitals effectively cope with COVID-19

Ying ZHOU, Lingling WANG, Lieyun DING, Zhouping TANG

《工程管理前沿（英文）》 2020年第7卷第3期页码 459-460 doi: 10.1007/s42524-020-0113-5

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Experimental investigations on operating characteristics of a closed loop pulsating heat pipe

Yu WANG

《能源前沿（英文）》 2015年第9卷第2期页码 134-141 doi: 10.1007/s11708-015-0354-x

摘要： The operating mechanism of the pulsating heat pipe (PHP) is not well understood and the present technology cannot predict required design parameters for a given task. The aim of research work presented in this paper is to better understand the operation regimes of the PHP through experimental investigations. A series of experiments were conducted on a closed loop PHP with 5 turns made of copper capillary tube of 2 mm in inner diameter. Two different working fluids viz. ethanol and acetone were employed. The operating characteristics were studied for the variation of heat input, filling ratio (FR) and inclination angle of the tested device. The results strongly demonstrate the effect of the filling ratio of the working fluid on the operational stability and heat transfer capability of the device. Important insight into the operational characteristics of PHP has been obtained.

关键词： closed loop pulsating heat pipe thermal performance operation limit thermography

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Piezoelectric inertial robot for operating in small pipelines based on stick-slip mechanism: modeling

《机械工程前沿（英文）》 2022年第17卷第3期 doi: 10.1007/s11465-022-0697-z

摘要： Small pipes exist in industrial and biomedical fields, and require microrobots with high operational precision and large load capacity to inspect or perform functional tasks. A piezoelectric inertial pipeline robot using a “stick-slip” mechanism was proposed to address this requirement. In this study, the driving principle of the proposed robot was analyzed, and the strategy of the design scheme was presented. A dynamics model of the stick-slip system was established by combining the dynamics model of the driving foot system and the LuGre friction model, and the simulation analysis of the effect of system parameters on the operating trajectory was performed. An experimental system was established to examine the output characteristics of the proposed robot. Experimental results show that the proposed pipeline robot with inertial stick-slip mechanism has a great load capacity of carrying 4.6 times (70 g) its own mass and high positioning accuracy. The speed of the pipeline robot can reach up to 3.5 mm/s (3 mm/s) in the forward (backward) direction, with a minimum step distance of 4 μm. Its potential application for fine operation in the pipe is exhibited by a demonstration of contactless transport.

关键词： pipeline robot piezoelectric inertial drive stick-slip large load capacity dynamics model small pipeline

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近程毫米波合成孔径辐射计被动测距原理

王本庆,李兴国

《中国工程科学》 2010年第12卷第3期页码 95-99

摘要：

毫米波合成孔径技术利用了物体自身辐射电磁波的相位信息，采用很少阵元就能实现实时成像，但目前合成孔径技术只是限于亮温成像，缺少了目标的距离信息，这对于目标探测与识别很不利。提出在近程条件下合成孔径被动测距原理和相应的双正交傅立叶变换算法，并给出了近程距离分辨率公式，近程成像的特点是成像公式中存在二次相位因子，而且距离分辨率和距离的平方成反比。毫米波合成孔径被动成像可以同时得到物体辐射的亮温分布和距离分布，能够有效克服离焦引起的图像模糊，对图像的反降晰和目标识别具有重要意义。

关键词：毫米波辐射计合成孔径近程成像被动测距 BFT

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An experimental study for optimization of high range water reducing superplasticizer in self compacting

Rahul DUBEY, Pardeep KUMAR

《结构与土木工程前沿（英文）》 2013年第7卷第1期页码 62-71 doi: 10.1007/s11709-013-0192-z

摘要： Concrete is extensively used construction material in the infrastructure development industry. With increase in technical knowhow, the need of research for high performance concretes such as self-compacting concrete (SCC) has increased in the last decade. The adaptability of SCC is due to its fluidic behavior in fresh state. However, to develop SCC using indigenous materials, the lack of standardized mix design procedures is the biggest impediment. Although with the advent of chemical admixtures, it is possible to achieve concrete with high fluidity, but at the same time durability issues require more attention. To have these fresh state properties SCC mixes are typically designed with high powder contents, and chemical admixtures. Proportioning and optimization of these materials is a key issue in the mix design of SCC. This paper focuses mainly on experimental study to optimize dosages of superplasticizer for mortar of SCC and then in concrete mixture itself.

关键词： self-compacting concrete (SCC) fresh properties superplasticizer optimization compressive strength

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A rank-based multiple-choice secretary algorithm for minimising microgrid operating cost under uncertainties

《能源前沿（英文）》 2023年第17卷第2期页码 198-210 doi: 10.1007/s11708-023-0874-8

摘要： The increasing use of distributed energy resources changes the way to manage the electricity system. Unlike the traditional centralized powered utility, many homes and businesses with local electricity generators have established their own microgrids, which increases the use of renewable energy while introducing a new challenge to the management of the microgrid system from the mismatch and unknown of renewable energy generations, load demands, and dynamic electricity prices. To address this challenge, a rank-based multiple-choice secretary algorithm (RMSA) was proposed for microgrid management, to reduce the microgrid operating cost. Rather than relying on the complete information of future dynamic variables or accurate predictive approaches, a lightweight solution was used to make real-time decisions under uncertainties. The RMSA enables a microgrid to reduce the operating cost by determining the best electricity purchase timing for each task under dynamic pricing. Extensive experiments were conducted on real-world data sets to prove the efficacy of our solution in complex and divergent real-world scenarios.

关键词： energy management systems demand response scheduling under uncertainty renewable energy sources multiple-choice secretary algorithm