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2022全球十大工程成就 2

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Optimal design of steel skeletal structures using the enhanced genetic algorithm methodology

Tugrul TALASLIOGLU

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 863-889 doi: 10.1007/s11709-019-0523-9

摘要: This study concerns with the design optimization of steel skeletal structures thereby utilizing both a real-life specification provisions and ready steel profiles named hot-rolled I sections. For this purpose, the enhanced genetic algorithm methodology named EGAwMP is utilized as an optimization tool. The evolutionary search mechanism of EGAwMP is constituted on the basis of generational genetic algorithm (GGA). The exploration capacity of EGAwMP is improved in a way of dividing an entire population into sub-populations and using of a radial basis neural network for dynamically adjustment of EGAwMP’s genetic operator parameters. In order to improve the exploitation capability of EGAwMP, the proposed neural network implementation is also utilized for prediction of more accurate design variables associating with a new design strategy, design codes of which are based on the provisions of LRFD_AISC V3 specification. EGAwMP is applied to determine the real-life ready steel profiles for the optimal design of skeletal structures with 105, 200, 444, and 942 members. EGAwMP accomplishes to increase the quality degrees of optimum designations Furthermore, the importance of using the real-life steel profiles and design codes is also demonstrated. Consequently, EGAwMP is suggested as a design optimization tool for the real-life steel skeletal structures.

关键词: design optimization     genetic algorithm     multiple populations     neural network    

Characterising populations living close to intensive farming and composting facilities in England

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1332-z

摘要:

• Bioaerosol emitted from farming and composting facilities may pose health risks.

关键词: Composting     Intensive farming     Bioaerosol     Population characteristics     Public health    

RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

《农业科学与工程前沿(英文)》 2021年 第8卷 第3期   页码 400-415 doi: 10.15302/J-FASE-2021394

摘要:

Since the F5 (2005), three winter wheat composite cross populations (CCPs) based on germplasm specifically suitable for low-input conditions were subjected to natural selection under organic and conventional management. In the F6, each CCP was divided into two parallel populations (12 CCPs in total) and maintained continuously until 2018. Commonly used modern cultivars with different disease susceptibilities were grown alongside to assess the agronomic performance of the CCPs. The organically managed CCPs were comparable in yield and foliar disease resistance to two continuously used reference cultivars, Achat and Capo. In contrast, under conventional management the cv. Capo outyielded the CCPs (Achat was not tested), highlighting the importance of parental cultivar choice for specific management systems. The CCPs were found to be moderately resistant to brown rust and even to the newly emerged stripe rust races prevalent in Europe since 2011. Differences between the CCPs were mainly due to parental genetic background and were significant in the first five generations, but were no longer so in the last five generations. In addition, these differences tended to vary depending on the experimental year and the environmental stresses present. In conclusion, the CCPs despite being derived from older cultivars are able to compete with more recently released reference cultivars under organic farming practices and represent a dynamic germplasm resource.

 

关键词: evolutionary breeding     heterogeneous crop population     management system    

Diverse bacterial populations of PM in urban and suburb Shanghai, China

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1329-7

摘要:

• Urban aerosols harbour diverse bacterial communities in Shanghai.

关键词: PM2.5     Bacteria     16S rRNA     SEM analysis     Shanghai City    

Anaerobic phenanthrene biodegradation with four kinds of electron acceptors enriched from the same mixed inoculum and exploration of metabolic pathways

Zuotao Zhang, Chongyang Wang, Jianzhong He, Hui Wang

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1164-x

摘要: Anaerobic phenanthrene biodegradation enriched process was described in detail. The enriched bacterial communities were characterized under four redox conditions. The enriched archaeal communities were stated under high percentage conditions. Relatively intact pathways of anaerobic phenanthrene biodegradation were proposed. Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent contaminants worldwide, especially in environments devoid of molecular oxygen. For lack of molecular oxygen, researchers enhanced anaerobic zones PAHs biodegradation by adding sulfate, bicarbonate, nitrate, and iron. However, microbial community reports of them were limited, and information of metabolites was poor except two-ring PAH, naphthalene. Here, we reported on four phenanthrene-degrading enrichment cultures with sulfate, bicarbonate, nitrate, and iron as electron acceptors from the same initial inoculum. The high-to-low order of the anaerobic phenanthrene biodegradation rate was the nitrate-reducing conditions>sulfate-reducing conditions>methanogenic conditions>iron-reducing conditions. The dominant bacteria populations were Desulfobacteraceae, Anaerolinaceae, and Thermodesulfobiaceae under sulfate-reducing conditions; Moraxellaceae, Clostridiaceae, and Comamonadaceae under methanogenic conditions; Rhodobacteraceae, Planococcaceae, and Xanthomonadaceae under nitrate-reducing conditions; and Geobacteraceae, Carnobacteriaceae, and Anaerolinaceae under iron-reducing conditions, respectively. Principal component analysis (PCA) indicated that bacteria populations of longtime enriched cultures with four electron acceptors all obtained significant changes from original inoculum, and bacterial communities were similar under nitrate-reducing and iron-reducing conditions. Archaea accounted for a high percentage under iron-reducing and methanogenic conditions, and Methanosarcinaceae and Methanobacteriaceae, as well as Methanobacteriaceae, were the dominant archaea populations under iron-reducing and methanogenic conditions. The key steps of phenanthrene biodegradation under four reducing conditions were carboxylation, further ring system reduction, and ring cleavage.

关键词: Phenanthrene     Anaerobic biodegradation     Bacterial populations     Archaea populations     Metabolic pathway    

arsenic in soil from brownfield sites in Beijing (China): statistical characterization of the background populations

Marina ACCORNERO,Lin JIANG,Eugenio NAPOLI,Marco CREMONINI,Giovanni FERRO,Federica BELLORO,Maosheng ZHONG

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 465-474 doi: 10.1007/s11783-014-0678-5

摘要: A probabilistic analysis was performed on soil arsenic concentration data from 4 brownfield sites at Beijing (Chaoyang and Haidian Districts), involved in environmental assessment studies. The available data sets were processed to provide a statistical characterization of the background populations and differentiate “anomalous data” from the natural range of variation of arsenic concentrations in soil. The site-specific background distributions and the existing wide-scale background values defined for the Beijing area were compared, discussing related implications for the definition of metal contamination soil screening levels (SSLs) in site assessment studies. The statistical analysis of As data sets discriminated site-specific background populations, encompassing 88% to 94% of the sample data, from outliers values, associated with either subsoil natural enrichments or possible anthropogenic releases. Upper Baseline Concentration ( ) limits (+ 2 level), including most of the site-specific metal background variability, were derived based on the statistical characterization of the background populations. Sites in the Chaoyang South District area had values in the range 10.4–12.6 mg·kg . These ranges provide meaningful SSL values to be adopted for As in local site assessment studies. Using the wide-scale background value for the Beijing area would have erroneously classified most of the areas in the subject sites as potentially contaminated.

关键词: upper baseline concentration     site assessment     arsenic     probability plot    

An assessment of surrogate fuel using Bayesian multiple kernel learning model in sight of sooting tendency

《能源前沿(英文)》 2022年 第16卷 第2期   页码 277-291 doi: 10.1007/s11708-021-0731-6

摘要: An integrated and systematic database of sooting tendency with more than 190 kinds of fuels was obtained through a series of experimental investigations. The laser-induced incandescence (LII) method was used to acquire the 2D distribution of soot volume fraction, and an apparatus-independent yield sooting index (YSI) was experimentally obtained. Based on the database, a novel predicting model of YSI values for surrogate fuels was proposed with the application of a machine learning method, named the Bayesian multiple kernel learning (BMKL) model. A high correlation coefficient (0.986) between measured YSIs and predicted values with the BMKL model was obtained, indicating that the BMKL model had a reliable and accurate predictive capacity for YSI values of surrogate fuels. The BMKL model provides an accurate and low-cost approach to assess surrogate performances of diesel, jet fuel, and biodiesel in terms of sooting tendency. Particularly, this model is one of the first attempts to predict the sooting tendencies of surrogate fuels that concurrently contain hydrocarbon and oxygenated components and shows a satisfying matching level. During surrogate formulation, the BMKL model can be used to shrink the surrogate candidate list in terms of sooting tendency and ensure the optimal surrogate has a satisfying matching level of soot behaviors. Due to the high accuracy and resolution of YSI prediction, the BMKL model is also capable of providing distinguishing information of sooting tendency for surrogate design.

关键词: sooting tendency     yield sooting index     Bayesian multiple kernel learning     surrogate assessment     surrogate formulation    

Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

《医学前沿(英文)》 2008年 第2卷 第2期   页码 171-173 doi: 10.1007/s11684-008-0031-0

摘要: This study aimed to investigate the treatment outcomes of esophageal variceal bleeding (EVB) in China. A total of 1087 cases were collected from 19 hospitals in 16 large and medium sized cities across China between January 1st, 2005 and January 1st, 2006. There were 313 cases (29.0%) of mild (<400 mL), 494 cases (45.8%) of moderate (400–1500 mL) and 272 cases (25.2%) of severe (>1500 mL) bleeding. Successful hemostasis was achieved in 89.8% of cases. Seven hundred and eighty-five cases were treated by medication with a hemostasis rate of 91.8%. Seventy-one cases were treated using a Sengstaken-Blakemore tube with a hemostasis rate of 54.9%. Thirty-seven cases were treated with emergency endoscopic variceal ligation with a hemostasis rate of 83.8%. Seventy-seven cases were treated with endoscopic sclerotherapy with a hemostasis rate of 94.8%. Forty-three cases were treated with emergency surgical operation with a hemostasis rate of 95.3%. Sixty-six cases were treated with combined therapy with a hemostasis rate of 97.0%. There was a significant difference ( < 0.01) in the successful hemostasis rate between different treatments. The overall mortality was 10.1%, among which 6.6% was directly caused by bleeding. The multivariate logistic regression analysis shows that the severity of bleeding, treatment methods, liver dysfunction and activation of hepatitis were predictive factors for successful hemostasis. Most cases of EVB were mild and moderate in severity. The first-line treatment for EVB is medication. Emergency endoscopic intervention has not been widely available yet. The overall management outcome of EVB has been improved.

关键词: significant difference     predictive     medication     first-line treatment     bleeding    

多天线非正交多址接入技术:综述 Regular Papers

Fei-yan TIAN, Xiao-ming CHEN

《信息与电子工程前沿(英文)》 2019年 第20卷 第12期   页码 1665-1697 doi: 10.1631/FITEE.1900405

摘要: 作为一种前沿的物理层技术,非正交多址接入技术允许多用户共享同一时空资源,因此增加了可接入用户数量,从而改善频谱效率。在第5代及未来无线通信网络中,非正交多址接入技术为实现大规模万物互联提供了可行方案。然而,严重的共道干扰和较高的实施复杂度阻碍了其在实际系统中的应用。为解决这些问题,多天线技术凭借其在空间自由度上的优势,已被广泛应用于非正交多址接入系统。本文针对多天线技术在非正交多址接入系统中各种各样的应用提供了一个全面综述,主要强调其在消除空间干扰和降低实施复杂度上的优势。特别地,详细调查了多天线技术在两用户、多用户、大规模连接和异构非正交多址接入系统中的应用。最后,预测了未来相关研究方向与挑战。

关键词: 非正交多址接入;多天线技术;B5G;物联网    

Sequential degradation-based burn-in test with multiple periodic inspections

《工程管理前沿(英文)》 2021年 第8卷 第4期   页码 519-530 doi: 10.1007/s42524-021-0166-0

摘要: Burn-in has been proven effective in identifying and removing defective products before they are delivered to customers. Most existing burn-in models adopt a one-shot scheme, which may not be sufficient enough for identification. Borrowing the idea from sequential inspections for remaining useful life prediction and accelerated lifetime test, this study proposes a sequential degradation-based burn-in model with multiple periodic inspections. At each inspection epoch, the posterior probability that a product belongs to a normal one is updated with the inspected degradation level. Based on the degradation level and the updated posterior probability, a product can be disposed, put into field use, or kept in the test till the next inspection epoch. We cast the problem into a partially observed Markov decision process to minimize the expected total burn-in cost of a product, and derive some interesting structures of the optimal policy. Then, algorithms are provided to find the joint optimal inspection period and number of inspections in steps. A numerical study is also provided to illustrate the effectiveness of our proposed model.

关键词: burn-in     degradation     multiple inspections     Wiener process     partially observed Markov decision process    

Sensitivity analysis of the deterioration of concrete strength in marine environment to multiple corrosive

《结构与土木工程前沿(英文)》 2023年 第17卷 第2期   页码 175-190 doi: 10.1007/s11709-021-0791-z

摘要: The corrosion degradation behavior of concrete materials plays a crucial role in the change of its mechanical properties under multi-ion interaction in the marine environment. In this study, the variation in the macro-physical and mechanical properties of concrete with corrosion time is investigated, and the source of micro-corrosion products under different salt solutions in seawater are analyzed. Regardless of the continuous hydration effect of concrete, the damage effects of various corrosive ions (Cl, SO42, and Mg2+, etc.) on the tensile and compressive strength of concrete are discussed based on measurement in different salt solutions. The sensitivity analysis method for concrete strength is used to quantitatively analyze the sensitivity of concrete strength to the effects of each ion in a multi-salt solution without considering the influence of continued hydration. The quantitative results indicate that the addition of Cl can weaken the corrosion effect of SO42 by about 20%, while the addition of Mg2+ or Mg2+ and Cl can strengthen it by 10%–20% during a 600-d corrosion process.

关键词: sensitivity analysis     concrete strength     corrosion deterioration     multi-ion interaction     marine environment    

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 798-813 doi: 10.1007/s11465-021-0645-3

摘要: External pipe routing for aero-engine in limited three-dimensional space is a typical nondeterministic polynomial hard problem, where the parallel layout of pipes plays an important role in improving the utilization of layout space, facilitating pipe assembly, and maintenance. This paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel layout. The compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be routed. Based on these rough paths, the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree, respectively. Subsequently, a coevolutionary improved differential evolution algorithm, which adopts the coevolutionary strategy, is used to solve multiple pipe layout optimization problem. By using this algorithm, pipes in the same group share the layout space information with one another, and the optimal layout solution of pipes in this group can be obtained in the same evolutionary progress. Furthermore, to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly, an accurate parallelization processing method based on the simulated annealing algorithm is proposed. Finally, the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词: multiple pipe routing     optimization algorithm     aero-engine     pipe grouping     parallel layout    

Surface accuracy optimization of mechanical parts with multiple circular holes for additive manufacturing

Jinghua XU, Hongsheng SHENG, Shuyou ZHANG, Jianrong TAN, Jinlian DENG

《机械工程前沿(英文)》 2021年 第16卷 第1期   页码 133-150 doi: 10.1007/s11465-020-0610-6

摘要: Surface accuracy directly affects the surface quality and performance of mechanical parts. Circular hole, especially spatial non-planar hole set is the typical feature and working surface of mechanical parts. Compared with traditional machining methods, additive manufacturing (AM) technology can decrease the surface accuracy errors of circular holes during fabrication. However, an accuracy error may still exist on the surface of circular holes fabricated by AM due to the influence of staircase effect. This study proposes a surface accuracy optimization approach for mechanical parts with multiple circular holes for AM based on triangular fuzzy number (TFN). First, the feature lines on the manifold mesh are extracted using the dihedral angle method and normal tensor voting to detect the circular holes. Second, the optimal AM part build orientation is determined using the genetic algorithm to optimize the surface accuracy of the circular holes by minimizing the weighted volumetric error of the part. Third, the corresponding weights of the circular holes are calculated with the TFN analytic hierarchy process in accordance with the surface accuracy requirements. Lastly, an improved adaptive slicing algorithm is utilized to reduce the entire build time while maintaining the forming surface accuracy of the circular holes using digital twins via virtual printing. The effectiveness of the proposed approach is experimentally validated using two mechanical models.

关键词: surface accuracy optimization     multiple circular holes     additive manufacturing (AM)     part build orientation     triangular fuzzy number (TFN)     digital twins    

Concentrating aqueous hydrochloric acid by multiple-effect membrane distillation

Rongling LIU, Yingjie QIN, Xiaojun LI, Liqiang LIU

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 311-321 doi: 10.1007/s11705-012-1207-3

摘要: Multiple-effect membrane distillation (MEMD) using a hollow fiber-based air-gap membrane distillation module was experimentally examined for concentrating dilute aqueous hydrochloric acid. The effects of the hot and cold feed-in temperatures, and the feed-in volumetric flow rates on the performance of the MEMD process were studied. The performance was evaluated using the performance ratio ( ), the average selectivity of water over HCl ( ) and the permeation flux ( ). Two types of porous fibers made from polypropylene were used to fabricate the MEMD modules. The experimental data indicated that hollow fibers with high porosity were preferred for the MEMD process. The , and all decreased as the feed concentration increased. When the feed concentration was below 12 wt-%, the was 6.0 – 9.6 and was 10 – 190. When the concentration of HCl reached 18 wt-%, the and were about 4.4 and 2.3, respectively. However, sharply decreased to around 1.0 when the feed was further concentrated. During an operational stability test that lasted for 30 days, the performance of the MEMD modules remained good.

关键词: multiple-effect membrane distillation     performance ratio     hydrochloric acid     recovery     stability    

Impacts of solar multiple on the performance of direct steam generation solar power tower plant with

Yan LUO, Xiaoze DU, Lijun YANG, Chao XU, Muhammad AMJAD

《能源前沿(英文)》 2017年 第11卷 第4期   页码 461-471 doi: 10.1007/s11708-017-0503-5

摘要: Solar multiple (SM) and thermal storage capacity are two key design parameters for revealing the performance of direct steam generation (DSG) solar power tower plant. In the case of settled land area, SM and thermal storage capacity can be optimized to obtain the minimum levelized cost of electricity (LCOE) by adjusting the power generation output. Taking the dual-receiver DSG solar power tower plant with a given size of solar field equivalent electricity of 100 MW in Sevilla as a reference case, the minimum LCOE is 21.77 ¢/kWh with an SM of 1.7 and a thermal storage capacity of 3 h. Besides Sevilla, two other sites are also introduced to discuss the influence of annual DNI. When compared with the case of Sevilla, the minimum LCOE and optimal SM of the San Jose site change just slightly, while the minimum LCOE of the Bishop site decreases by 32.8% and the optimal SM is reduced to 1.3. The influence of the size of solar field equivalent electricity is studied as well. The minimum LCOE decreases with the size of solar field, while the optimal SM and thermal storage capacity still remain unchanged. In addition, the sensitivity of different investment in sub-system is investigated. In terms of optimal SM and thermal storage capacity, they can decrease with the cost of thermal storage system but increase with the cost of power generation unit.

关键词: direct steam generation     solar power tower     solar multiple     thermal energy storage capacity     levelized cost of electricity (LCOE)    

标题 作者 时间 类型 操作

Optimal design of steel skeletal structures using the enhanced genetic algorithm methodology

Tugrul TALASLIOGLU

期刊论文

Characterising populations living close to intensive farming and composting facilities in England

期刊论文

RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

期刊论文

Diverse bacterial populations of PM in urban and suburb Shanghai, China

期刊论文

Anaerobic phenanthrene biodegradation with four kinds of electron acceptors enriched from the same mixed inoculum and exploration of metabolic pathways

Zuotao Zhang, Chongyang Wang, Jianzhong He, Hui Wang

期刊论文

arsenic in soil from brownfield sites in Beijing (China): statistical characterization of the background populations

Marina ACCORNERO,Lin JIANG,Eugenio NAPOLI,Marco CREMONINI,Giovanni FERRO,Federica BELLORO,Maosheng ZHONG

期刊论文

An assessment of surrogate fuel using Bayesian multiple kernel learning model in sight of sooting tendency

期刊论文

Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

期刊论文

多天线非正交多址接入技术:综述

Fei-yan TIAN, Xiao-ming CHEN

期刊论文

Sequential degradation-based burn-in test with multiple periodic inspections

期刊论文

Sensitivity analysis of the deterioration of concrete strength in marine environment to multiple corrosive

期刊论文

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

期刊论文

Surface accuracy optimization of mechanical parts with multiple circular holes for additive manufacturing

Jinghua XU, Hongsheng SHENG, Shuyou ZHANG, Jianrong TAN, Jinlian DENG

期刊论文

Concentrating aqueous hydrochloric acid by multiple-effect membrane distillation

Rongling LIU, Yingjie QIN, Xiaojun LI, Liqiang LIU

期刊论文

Impacts of solar multiple on the performance of direct steam generation solar power tower plant with

Yan LUO, Xiaoze DU, Lijun YANG, Chao XU, Muhammad AMJAD

期刊论文