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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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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)    

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Supplier selection and order splitting in multiple-sourcing inventory systems

WANG Guicong, JIANG Zhaoliang, LI Zhaoqian, LIU Wenping

《机械工程前沿（英文）》 2008年 第3卷 第1期   页码 23-27 doi: 10.1007/s11465-008-0016-3

摘要： Supplier selection and inventory control are critical decision processes in single-item multiple-supplier systems. An integer linear programming model is proposed to help managers determine the reorder level, choose the best suppliers, and place the optimum order quantities so that the total average inventory cost is minimum, and constraints of supplier ability, quality, and demand are considered. An algorithm combining the branch-bound algorithm and enumeration algorithm is developed to solve the problems. Application of the proposed model in an automobile industry shows that it is effective.

关键词： automobile industry     branch-bound algorithm     selection     single-item multiple-supplier     effective    

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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    

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Gastrointestinal damage caused by swallowing multiple magnets

null

《医学前沿（英文）》 2012年 第6卷 第3期   页码 280-287 doi: 10.1007/s11684-012-0207-5

摘要：

Swallowing multiple magnets is not uncommon worldwide and it frequently leads to serious consequences. However, most patients fail to receive timely and correct diagnosis and treatment. A literature search was performed to establish an algorithm for these accidents by the authors to identify relevant articles published from June 1987 to October 2010 in Google, Medline, ISI Web of Knowledge Ovid, CNKI, Korea Med and library document delivery, using search terms “magnet ingestion, ” “fistula, ” and “perforation. ” A total of 149 patients with ingestion of magnetic foreign bodies from 20 countries and areas were identified. 22 of them were companioned with neurological and psychiatric disorders. Swallowing magnets occurred throughout childhood and adolescent, mostly ranging 2 to 4 years in age. Various gastrointestinal damages such as necrosis and intestinal perforation or fistula were encountered. Damage from swallowing multiple magnets carries a significant risk of morbidity and even mortality throughout childhood to adolescent worldwide. Older children and adults with neurological and psychiatric problems may be at high risk for such accidents. Early intervention is crucial.

关键词： magnet     ingestion     fistula     perforation    

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CHALLENGES PROVIDING MULTIPLE ECOSYSTEM BENEFITS FOR SUSTAINABLE MANAGED SYSTEMS

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 170-176 doi: 10.15302/J-FASE-2022444

摘要：

Since humans started practicing agriculture at the expense of natural forests, 8000 years ago, they have affected atmospheric CO2concentrations. Their impact on atmospheric CH4 started about 5000 years ago, as result of the cultivation of paddy rice. A challenge of modern agricultural practices is to reverse the impact cropping has had on greenhouse gas emissions and the global climate. There is an increasing demand for agriculture to provide food security as well as a range of other ecosystem services. Depending on ecosystem management, different practices may involve trade-offs and synergies, and these must be considered to work toward desirable management systems. Solution toward food security should not only focus on agricultural management practices, but also on strategies to reduce food waste, more socially-just distribution of resources, changes in lifestyle including decarbonization of the economy, as well as reducing human population growth.

关键词： crop diversification / ecosystem services / food security / sustainable cropping systems    

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多目标存在的多基地MIMO组网雷达与多干扰机之间的超模干扰抑制博弈 Research Article

赫彬1,2,苏洪涛1

《信息与电子工程前沿（英文）》 2022年 第23卷 第4期   页码 617-629 doi: 10.1631/FITEE.2000652

摘要： 为应对新一代电子战的威胁，本文建立一种非合作对抗博弈模型，分析了多基地多入多出（MIMO）雷达与多干扰机之间的功率分配和干扰抑制问题。首先，根据功率分配策略，构造了一种具有固定权矢量的超模功率分配博弈框架。同时，建立了一种极大化雷达效用函数的约束优化模型。基于效用函数，分别得到雷达和干扰机的最佳功率分配策略，并证明该超模博弈的纳什均衡的存在性和唯一性。然后，提出一种具有固定权矢量的超模博弈算法，该算法收敛于博弈的纳什均衡。此外，采用自适应波束形成方法抑制互通道干扰，如干扰机到雷达的直达波干扰。为抑制这些干扰，提出一种联合功率分配和波束形成的超模博弈算法。该算法在保证最佳功率分配的同时，提高了MIMO雷达的干扰抑制能力。最后通过数值结果验证了两种算法的优越性和收敛性。

关键词： 超模博弈；功率分配；波束形成；多入多出雷达；多干扰机    

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characterization of Cu binding potential of dissolved organic matter (DOM) in sediment from Taihu Lake using multiple

Yuan ZHANG,Yan ZHANG,Tao YU

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 666-674 doi: 10.1007/s11783-013-0608-y

摘要： Dissolved organic matter (DOM) plays an important role in heavy metal speciation and distribution in the aquatic environment especially for eutrophic lakes which have higher DOM concentration. Taihu Lake is the third largest freshwater and a high eutrophic lake in the downstream of the Yangtze River, China. In the lake, frequent breakout of algae blooms greatly increased the concentration of different organic matters in the lake sediment. In this study, sediment samples were collected from various part of Taihu Lake to explore the spatial difference in the binding potential of DOM with Cu. The titration experiment was adopted to quantitatively characterize the interaction between Cu(II) and DOM extracted from Taihu Lake sediments using ion selective electrode (ISE) and fluorescence quenching technology. The ISE results showed that the exogenous DOM had higher binding ability than endogenous DOM, and DOM derived from aquatic macrophytes had a higher binding ability than that derived from algae. The fluorescence quenching results indicated that humic substances played a key role in the complexation between DOM and Cu(II) in the lake. However, because of the frequent breakout of algae blooms, protein-like matters are also main component like humic matters in Taihu Lake. Therefore, the metals bound by protein-like substances should be caused concern as protein-like substances in DOM were unstable and they will release bound metal when decomposed.

关键词： binding ability     dissolved organic matters     fluorescence quenching     complex capacity     Taihu Lake    

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标题 作者 时间 类型 操作

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

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

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

Supplier selection and order splitting in multiple-sourcing inventory systems

WANG Guicong, JIANG Zhaoliang, LI Zhaoqian, LIU Wenping

期刊论文

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

期刊论文

Gastrointestinal damage caused by swallowing multiple magnets

null

期刊论文

CHALLENGES PROVIDING MULTIPLE ECOSYSTEM BENEFITS FOR SUSTAINABLE MANAGED SYSTEMS

期刊论文

多目标存在的多基地MIMO组网雷达与多干扰机之间的超模干扰抑制博弈

赫彬1,2,苏洪涛1

期刊论文

characterization of Cu binding potential of dissolved organic matter (DOM) in sediment from Taihu Lake using multiple

Yuan ZHANG,Yan ZHANG,Tao YU

期刊论文