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Reduction of rough set attribute based on immune clone selection

LIANG Lin, XU Guang-hua

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 413-417 doi: 10.1007/s11465-006-0049-4

摘要: A novel attribute reduction approach of rough set based on immune clone selection is proposed. In this method, the approximation quality and attribute set were adopted as evolution object and antibody, respectively. On the basis of the inherent distribution within the immune response, the global optimization of the antibody was realized through parallel local optimization. Moreover, the diversity of the antibody population was maintained with the affinity maturation and renewal of the antibody. Thus, the stable multi-optimal solutions can be preserved. In addition, the machinery fault data were analyzed by this method, and the attribute reduction sets were obtained further to satisfy the demand of feature selection in machinery diagnosis.

关键词: inherent distribution     maturation     evolution     diversity     antibody    

Process synthesis with simultaneous consideration of inherent safety-inherent risk footprint

Andreja Nemet, Jiří J. Klemeš, Zdravko Kravanja

《化学科学与工程前沿(英文)》 2018年 第12卷 第4期   页码 745-762 doi: 10.1007/s11705-018-1779-7

摘要:

Process plants should be designed to be economically viable and environmentally friendly, while also being operable and maintainable during process implementation. The safety of processes is among the most important considerations in obtaining results that are more acceptably realistic, as it is linked to the availability and reliability of the process. Inherent safety can effectively be enhanced in the early stages of the design, when the main decisions on process design are made. The aim of this study is to enhance and select the appropriate risk assessment method and to incorporate it into process synthesis, using a mathematical programming approach. A mixed-integer, nonlinear programming (MINLP) model was used for the synthesis of a methanol production process, considering risk assessment during the synthesis. Risk assessment is performed simultaneously with the MINLP process synthesis, where the risk is determined either for the whole process as overall risk, or on a per unit-of-a-product basis. For the latter, a new measurement is proposed: the inherent risk footprint. The results of a case study led to two main conclusions: (i) Significantly safer designs can be obtained at negligible economic expense, and (ii) at higher production capacities, a lower inherent risk footprint can be achieved. The results also indicate that designs obtained using this method can have significantly increased inherent safety, while remaining economically viable.

关键词: inherent safety     process design     simultaneous risk assessment     risk footprint     methanol process    

Genome-wide association studies: inherent limitations and future challenges

null

《医学前沿(英文)》 2012年 第6卷 第4期   页码 444-450 doi: 10.1007/s11684-012-0225-3

摘要:

Genome-wide association studies (GWAS) have achieved great success in identifying genetic variants related to complex human diseases such as cancer and have provided valuable insights into their genetic architecture. Recently, GWAS is quite the fashion in China. However, there are issues related to its nature. Enormous work needs to be done in the post-GWAS era. Deep sequencing followed by functional studies will be needed to elucidate the underpinning biological mechanisms and further translate GWAS findings into medical practice. Along with pharmacogenomics, the success of GWAS in identifying genetic risk factors and genetic differences in drug response has been gradually enabling personalized medicine. In this article, we used hepatocellular carcinoma (HCC) as an example to demonstrate some of the inherent limitations and summarized future challenges of GWAS.

关键词: genome-wide association studies (GWAS)     genetic variant     cancer     limitation     challenge    

基于本质安全的工业事故风险管理方法研究

吴宗之

《中国工程科学》 2007年 第9卷 第5期   页码 46-49

摘要:

从风险管理角度对生产过程中的安全防护方法进行了分类和论述,提出了基于本质安全思想的工业 事故综合风险管理方法与程序,其核心内容是在常规的危险辨识和风险评价基础上,优先应用本质安全原理来 减少、消除危险,综合采用无源安全措施、有源安全措施或多层安全防护措施与功能安全标准,将风险降低至 可接受水平;提出了本质安全应与清洁生产、绿色化学、循环经济同等纳入优先发展的技术和政策等建议。

关键词: 本质安全     风险管理     事故预防     安全设计    

Development and testing of a wireless smart toolholder with multi-sensor fusion

《机械工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0774-y

摘要: The smart toolholder is the core component in the development of intelligent and precise manufacturing. It enables in situ monitoring of cutting data and machining accuracy evolution and has become a focal point in academic research and industrial applications. However, current table and rotational dynamometers for milling force, vibration, and temperature testing suffer from cumbersome installation and provide only a single acquisition signal, which limits their use in laboratory settings. In this study, we propose a wireless smart toolholder with multi-sensor fusion for simultaneous sensing of milling force, vibration, and temperature signals. We select force, vibration, and temperature sensors suitable for smart toolholder fusion to adapt to the cutting environment. Thereafter, structural design, circular runout, dynamic balancing, static stiffness, and dynamic inherent frequency tests are conducted to assess its dynamic and static performance. Finally, the smart toolholder is tested for accuracy and repeatability in terms of force, vibration, and temperature. Experimental results demonstrate that the smart toolholder accurately captures machining data with a relative deviation of less than 1.5% compared with existing force gauges and provides high repeatability of milling temperature and vibration signals. Therefore, it is a smart solution for machining condition monitoring.

关键词: wireless smart toolholder     multi-sensor fusion     circular runout     dynamic balancing     static stiffness     dynamic inherent frequency    

Numerical investigation and analysis of heat transfer enhancement in channel by longitudinal vortex based on field synergy principle

TAO Wenquan, WU Junmei

《能源前沿(英文)》 2008年 第2卷 第1期   页码 71-78 doi: 10.1007/s11708-008-0001-x

摘要: 3-D numerical simulations were presented for laminar flow and heat transfer characteristics in a rectangular channel with vortex generators. The effects of Reynolds number (from 800 to 3 000), the attack angle of vortex generator (from 15° to 90°) and the shape of vortex generator were examined. The numerical results were analyzed based on the field synergy principle. It is found that the inherent mechanism of the heat transfer enhancement by longitudinal vortex can be explained by the field synergy principle, that is, the second flow generated by vortex generators results in the reduction of the intersection angle between the velocity and fluid temperature gradient. The longitudinal vortex improves the field synergy of the large downstream region of longitudinal vortex generator (LVG) and the region near (LVG); however, transverse vortex only improves the synergy of the region near vortex generator. Thus, longitudinal vortex can enhance the integral heat transfer of the flow field, while transverse vortex can only enhance the local heat transfer. The synergy angle decreases with the increase of Reynolds number for the channel with LVG to differ from the result obtained from the plain channel, and the triangle winglet performs better than the rectanglar one under the same surface area condition.

关键词: inherent mechanism     integral     surface     rectanglar     longitudinal    

Numerical analysis on heat transfer enhancement by longitudinal vortex based on field synergy principle

WU Junmei, TAO Wenquan

《能源前沿(英文)》 2007年 第1卷 第3期   页码 365-369 doi: 10.1007/s11708-007-0055-1

摘要: Three-dimensional numerical simulation results are presented for a fin-and-tube heat transfer surface with vortex generators. The effects of the Reynolds number (from 800 to 2 000) and the attack angle (30º and 45º) of a delta winglet vortex generator are examined. The numerical results are analyzed on the basis of the field synergy principle to explain the inherent mechanism of heat transfer enhancement by longitudinal vortex. The secondary flow generated by the vortex generators causes the reduction of the intersection angle between the velocity and fluid temperature gradients. In addition, the computational evaluations indicate that the heat transfer enhancement of delta winglet pairs for an aligned tube bank fin-and-tube surface is more significant than that for a staggered tube bank fin-and-tube surface. The heat transfer enhancement of the delta winglet pairs with an attack angle of 45º is larger than that with an angle of 30º. The delta winglet pair with an attack angle of 45º leads to an increase in pressure drop, while the delta winglet pair with the 30º angle results in a slight decrease. The heat transfer enhancement under identical pumping power condition for the attack angle of 30º is larger than that for the attack angle of 45º either for staggered or for aligned tube bank arrangement.

关键词: computational     inherent mechanism     staggered     decrease     transfer surface    

Copper and zinc interaction on water clearance and tissue metal distribution in the freshwater mussel

Tianxiang XIA, Xuehua LIU

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 236-242 doi: 10.1007/s11783-010-0218-8

摘要: Copper and zinc interaction on clearance from water and distribution in different tissues was investigated for the freshwater mussel, , under laboratory conditions. Clearance rate of Cu or Zn from water was highly dependent on exposure concentration. Interaction effect was most evident at 300 μg·L Cu exposure and depressed the Zn clearance rate significantly ( <0.05). However, the presence of 100 μg·L and 300 μg·L Zn hardly affected the Cu clearance rate. The 300 μg·L Cu presence enhanced Cu accumulation in each tissue most significantly ( <0.01), but caused Zn content to decrease in the gills by 62% ( <0.05), viscera by 49% ( <0.05) and foot by 31% ( <0.05), and increase in the mantle by 97% ( <0.05) and the muscles by 243% ( <0.05) for different Zn exposure treatments. The response of metal accumulation in various tissues of the test mussels indicated that Zn transferred from the gills, viscera and foot to the mantle and muscles might be one of the important characteristics of the Zn regulatory mechanism by leading to a narrow range of Zn concentration in the different tissues.

关键词: interaction     mussel     copper     zinc     clearance     distribution    

Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 985-995 doi: 10.1007/s11705-021-2126-y

摘要: The high contents of nitrogen-containing organic compounds in biocrude obtained from hydrothermal liquefaction of microalgae are one of the most concerned issues on the applications and environment. In the project, Chlorella sp. and Spirulina sp. were selected as raw materials to investigate the influence of different reaction conditions (i.e., reaction temperature, residence time, solid loading rate) on the distribution of nitrogen in the oil phase and aqueous phase. Three main forms of nitrogen-containing organic compounds including nitrogen-heterocyclic compounds, amide, and amine were detected in biocrudes. The contents of nitrogen-heterocyclic compounds decreased with temperature while amide kept increasing. The effect of residence time on the components of nitrogen-containing organic compounds was similar with that of temperature. However, the influence of solid loading rate was insignificant. Moreover, it was also found that the differences of amino acids in the protein components in the two microalgae might affect the nitrogen distribution in products. For example, nitrogen in basic amino acids of Spirulina sp. preferred to go into the aqueous phase comparing with the nitrogen in neutral amino acids of Chlorella sp. In summary, a brief reaction map was proposed to describe the nitrogen pathway during microalgae hydrothermal liquefaction.

关键词: microalgae     hydrothermal liquefaction     biocrude     nitrogen distribution    

Thermodynamic models and energy distribution of single-phase heated surface in a boiler under unsteady

Xiyan GUO, Yongping YANG

《能源前沿(英文)》 2011年 第5卷 第1期   页码 69-74 doi: 10.1007/s11708-010-0117-7

摘要: A coal-fired power unit frequently operates under unsteady conditions; thus, in order to acquire scientific energy analysis of the unit, thermodynamic analysis of a single-phase heated surface in a boiler under such conditions requires investigation. Processes are analyzed, and distributions of energy and exergy are qualitatively revealed. Models for energy analysis, entropy analysis, and exergy analysis of control volumes and irreversible heat transfer processes are established. Taking the low-temperature superheater of a 610 t/h-boiler as an example, the distribution of energy, entropy production, and exergy is depicted quantitatively, and the results are analyzed.

关键词: thermodynamic model     energy distribution     boiler     unsteady conditions    

Estimation of distribution algorithm enhanced particle swarm optimization for water distribution network

Xuewei QI,Ke LI,Walter D. POTTER

《环境科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 341-351 doi: 10.1007/s11783-015-0776-z

摘要: The optimization of a water distribution network (WDN) is a highly nonlinear, multi-modal, and constrained combinatorial problem. Particle swarm optimization (PSO) has been shown to be a fast converging algorithm for WDN optimization. An improved estimation of distribution algorithm (EDA) using historic best positions to construct a sample space is hybridized with PSO both in sequential and in parallel to improve population diversity control and avoid premature convergence. Two water distribution network benchmark examples from the literature are adopted to evaluate the performance of the proposed hybrid algorithms. The experimental results indicate that the proposed algorithms achieved the literature record minimum (6.081 M$) for the small size Hanoi network. For the large size Balerma network, the parallel hybrid achieved a slightly lower minimum (1.921M?) than the current literature reported best minimum (1.923M?). The average number of evaluations needed to achieve the minimum is one order smaller than most existing algorithms. With a fixed, small number of evaluations, the sequential hybrid outperforms the parallel hybrid showing its capability for fast convergence. The fitness and diversity of the populations were tracked for the proposed algorithms. The track record suggests that constructing an EDA sample space with historic best positions can improve diversity control significantly. Parallel hybridization also helps to improve diversity control yet its effect is relatively less significant.

关键词: particle swarm optimization (PSO)     diversity control     estimation of distribution algorithm (EDA)     water distribution network (WDN)     premature convergence     hybrid strategy    

Hazard and vulnerability evaluation of water distribution system in cases of contamination intrusion

Kunlun XIN, Tao TAO, Yong WANG, Suiqing LIU

《环境科学与工程前沿(英文)》 2012年 第6卷 第6期   页码 839-848 doi: 10.1007/s11783-012-0409-8

摘要: In this paper, it proposed an index system for hazard and vulnerability evaluations of water distribution networks, based on the simulation of contamination events caused by pollutant injections at different junctions. It attempted to answer the following two questions in the case of contamination events: 1) Which are the most hazardous junctions? 2) Which are the most vulnerable junctions? With EPANET toolkit, it simulated the propagation of the contaminant, and calculated the peak concentration of the contaminant and mass delivered at different nodes. According to types of consumers, different weights were assigned to the consumer nodes for assessing the influence of the contaminant on the consumers. Using the method proposed herein, both the hazard index and vulnerability index were calculated for each node in the pipe network. The presented method was therefore applied to the water network of the city of Zhenjiang, which contains two water plants, two booster pump stations with storage tanks. In conclusion, the response time, the relationships between the peak concentration of contaminant and the total absorption are the most important factors in hazard and vulnerability evaluation of the water distribution network.

关键词: water distribution network     hazard     vulnerability     contaminant accident    

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 241-248 doi: 10.1007/s11465-011-0219-x

摘要:

This paper presents a new calculation method that can calculate the load distribution on pipe threaded connections under tension load. On the basis of elastic mechanics, the new method was developed by analyzing each thread tooth, and a new deformation and covariant equation by making a mechanics analysis on each thread tooth was obtained. Compared with the traditional method proposed by the previous references, the new deformation and covariant equation could be used to describe the relation between the previous and the next thread tooth. By applying the new method on the sample of P-110S pipe threaded connection, the obtained results show that the load on thread tooth mainly concentrates on the four or five threads engaged and the middle teeth were not utilized well to bear the loads. The model offers a new way to calculate the loads carried on the thread teeth under tension load.

关键词: load distribution     calculation method     pipe threaded connections     tension load    

Numerical simulation of the heat flux distribution in a solar cavity receiver

Yueshe WANG, Xunwei DONG, Jinjia WEI, Hui JIN

《能源前沿(英文)》 2011年 第5卷 第1期   页码 98-103 doi: 10.1007/s11708-010-0019-8

摘要: In the solar tower power plant, the receiver is one of the main components of efficient concentrating solar collector systems. In the design of the receiver, the heat flux distribution in the cavity should be considered first. In this study, a numerical simulation using the Monte Carlo Method has been conducted on the heat flux distribution in the cavity receiver, which consists of six lateral faces and floor and roof planes, with an aperture of 2.0 m×2.0 m on the front face. The mathematics and physical models of a single solar ray’s launching, reflection, and absorption were proposed. By tracing every solar ray, the distribution of heat flux density in the cavity receiver was obtained. The numerical results show that the solar flux distribution on the absorbing panels is similar to that of CESA-I’s. When the reradiation from walls was considered, the detailed heat flux distributions were issued, in which 49.10% of the total incident energy was absorbed by the central panels, 47.02% by the side panels, and 3.88% was overflowed from the aperture. Regarding the peak heat flux, the value of up to 1196.406 kW/m was obtained in the center of absorbing panels. These results provide necessary data for the structure design of cavity receiver and the local thermal stress analysis for boiling and superheated panels.

关键词: solar cavity receiver     Monte Carlo method     heat flux distribution    

标题 作者 时间 类型 操作

Reduction of rough set attribute based on immune clone selection

LIANG Lin, XU Guang-hua

期刊论文

Process synthesis with simultaneous consideration of inherent safety-inherent risk footprint

Andreja Nemet, Jiří J. Klemeš, Zdravko Kravanja

期刊论文

Genome-wide association studies: inherent limitations and future challenges

null

期刊论文

基于本质安全的工业事故风险管理方法研究

吴宗之

期刊论文

Development and testing of a wireless smart toolholder with multi-sensor fusion

期刊论文

Numerical investigation and analysis of heat transfer enhancement in channel by longitudinal vortex based on field synergy principle

TAO Wenquan, WU Junmei

期刊论文

Numerical analysis on heat transfer enhancement by longitudinal vortex based on field synergy principle

WU Junmei, TAO Wenquan

期刊论文

Copper and zinc interaction on water clearance and tissue metal distribution in the freshwater mussel

Tianxiang XIA, Xuehua LIU

期刊论文

Nitrogen distribution in the products from the hydrothermal liquefaction of sp. and sp.

期刊论文

Thermodynamic models and energy distribution of single-phase heated surface in a boiler under unsteady

Xiyan GUO, Yongping YANG

期刊论文

Estimation of distribution algorithm enhanced particle swarm optimization for water distribution network

Xuewei QI,Ke LI,Walter D. POTTER

期刊论文

Hazard and vulnerability evaluation of water distribution system in cases of contamination intrusion

Kunlun XIN, Tao TAO, Yong WANG, Suiqing LIU

期刊论文

Calculation method of load distribution on pipe threaded connections under tension load

Shoujun CHEN, Lianxin GAO, Qi AN

期刊论文

Nikos Hatziargyrio:The Role of Data in Intelligent Distribution Grids(2022年6月6日)

2022年07月07日

会议视频

Numerical simulation of the heat flux distribution in a solar cavity receiver

Yueshe WANG, Xunwei DONG, Jinjia WEI, Hui JIN

期刊论文