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k-ε模型 2

三点弯曲梁 2

深度学习 2

&alpha 1

/III-V界面 1

CO₂ 加氢 1

Chrestenson谱 1

K 助剂 1

K型钢管混凝土节点 1

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K波段；高效率；宽带；氮化镓（GaN）；功率放大器 1

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SNP芯片 1

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钾/锰助剂对氮掺杂碳纳米管负载铁基催化剂在CO₂加氢过程中的影响研究 Article

Praewpilin Kangvansura, Ly May Chew, Chanapa Kongmark, Phatchada Santawaja, Holger Ruland, Wei Xia, Hans Schulz, Attera Worayingyong, Martin Muhler

《工程（英文）》 2017年第3卷第3期页码 385-392 doi: 10.1016/J.ENG.2017.03.013

摘要：

氮掺杂碳纳米管(NCNTs) 作为载体负载铁(Fe) 纳米颗粒，可应用于CO₂多相催化加氢反应(633 K和25 bar)。当将钾(K) 和锰(Mn) 作为助催化剂时，Fe/NCNT 展现出优异的CO₂ 加氢性能，在体积空速(GHSV) 为3.1 L·(g·h)^{&ndash当使用K 作为助催化剂时，反应对烯烃和短链烷烃具有高的选择性。当K 和Mn 同时作为助催化剂时，其催化活性能够稳定地维持60 h。当K 和Mn 作为助催化剂时，Fe/NCNT 具有最好的催化活性。在还原条件下，当K 作为助催化剂时，Fe/NCNT 具有最优异的热稳定性。}

关键词： CO₂ 加氢铁基催化剂 n 型碳纳米管 Mn 助剂 K 助剂

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Update on Mayer–Rokitansky–Küster–Hauser syndrome

《医学前沿（英文）》 2022年第16卷第6期页码 859-872 doi: 10.1007/s11684-022-0969-3

摘要： This review presents an update of Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome on its etiologic, clinical, diagnostic, psychological, therapeutic, and reproductive aspects. The etiology of MRKH syndrome remains unclear due to its intrinsic heterogeneity. Nongenetic and genetic causes that may interact during the embryonic development have been proposed with no definitive etiopathogenesis identified. The proportion of concomitant extragenital malformations varies in different studies, and the discrepancies may be explained by ethnic differences. In addition to physical examination and pelvic ultrasound, the performance of pelvic magnetic resonance imaging is crucial in detecting the presence of rudimentary uterine endometrium. MRKH syndrome has long-lasting psychological effects on patients, resulting in low esteem, poor coping strategies, depression, and anxiety symptoms. Providing psychological counseling and peer support to diagnosed patients is recommended. Proper and timely psychological intervention could significantly improve a patient’s outcome. Various nonsurgical and surgical methods have been suggested for treatment of MRKH syndrome. Due to the high success rate and minimal risk of complications, vaginal dilation has been proven to be the first-line therapy. Vaginoplasty is the second-line option for patients experiencing dilation failure. Uterine transplantation and gestational surrogacy are options for women with MRKH syndrome to achieve biological motherhood.

关键词： MRKH (Mayer–Rokitansky–Küster–Hauser) syndrome etiology clinical characteristic diagnosis treatment psychological effect

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用智能药丸提供胰岛素？

Elizabeth K. Wilson

《工程（英文）》 2019年第5卷第4期页码 603-604 doi: 10.1016/j.eng.2019.07.008

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Stochastic analysis of laminated composite plate considering stochastic homogenization problem

SAKATA,K. OKUDA,K. IKEDA

《结构与土木工程前沿（英文）》 2015年第9卷第2期页码 141-153 doi: 10.1007/s11709-014-0286-2

摘要： This paper discusses a multiscale stochastic analysis of a laminated composite plate consisting of unidirectional fiber reinforced composite laminae. In particular, influence of a microscopic random variation of the elastic properties of component materials on mechanical properties of the laminated plate is investigated. Laminated composites are widely used in civil engineering, and therefore multiscale stochastic analysis of laminated composites should be performed for reliability evaluation of a composite civil structure. This study deals with the stochastic response of a laminated composite plate against the microscopic random variation in addition to a random variation of fiber orientation in each lamina, and stochastic properties of the mechanical responses of the laminated plate is investigated. Halpin-Tsai formula and the homogenization theory-based finite element analysis are employed for estimation of effective elastic properties of lamina, and the classical laminate theory is employed for analysis of a laminated plate. The Monte-Carlo simulation and the first-order second moment method with sensitivity analysis are employed for the stochastic analysis. From the numerical results, importance of the multiscale stochastic analysis for reliability evaluation of a laminated composite structure and applicability of the sensitivity-based approach are discussed.

关键词： stochastic homogenization multiscale stochastic analysis microscopic random variation laminated composite plate

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Shape control of multi-cellular inflatable panels

KATAYAMA, K. ISHIMURA, K. MINESUGI, DANIEL J. INMAN

《机械工程前沿（英文）》 2013年第8卷第3期页码 276-282 doi: 10.1007/s11465-013-0267-5

摘要：

Multi-cellular inflatable structures are ultra-light and robust against membrane damage such as pinholes caused by space debris. Due to their robustness, inflatable structures supported by inner gases can be applied as space structures. In the present study, shape control for a simple multi-cellular inflatable panel was achieved via a novel diaphragm mechanism. When the bending actuator in a center membrane bends, the inner pressures of sub-cells become different, and the diaphragm mechanism bends as a whole. Because a sliding component is not included, this deformable system is a reliable mechanism. In addition, the proposed mechanism has higher rigidity than that of a bending actuator used alone. In the present paper, we investigate the feasibility of a novel diaphragm mechanism and its characteristics using experimental and numerical results.

关键词： Membrane structures inflatable structure shape control smart structures structural mechanics space engineering

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A multi-attribute decision making approach of mix design based on experimental soil characterization

Amit K. BERA, Tanmoy MUKHOPADHYAY, Ponnada J. MOHAN, Tushar K. DEY

《结构与土木工程前沿（英文）》 2018年第12卷第3期页码 361-371 doi: 10.1007/s11709-017-0425-7

摘要：

The clay mineral composition is one of the major factors that governs the physical properties of silty sand subgrade. Therefore, a thorough knowledge of mineral composition is essential to predict the optimum engineering properties of the soil, which is generally characterized by different indices like maximum dry density (MDD), California bearing ratio (CBR), unconfined compressive strength (UCS) and free swelling index (FSI). In this article, a novel multi-attribute decision making (MADM) based approach of mix design has been proposed for silty sand – artificial clay mix to improve the characteristic strength of a soil subgrade. Experimental investigation has been carried out in this study to illustrate the proposed approach of selecting appropriate proportion for the soil mix to optimize all the above mentioned engineering properties simultaneously. The results show that a mix proportion containing approximately 90% silty sand plus 10% bentonite soil is the optimal combination in context to the present study. The proposed methodology for optimal decision making to choose appropriate combination of bentonite and silty sand is general in nature and therefore, it can be extended to other problems of selecting mineral compositions.

关键词： silty sand bentonite soil soil mix design multi-attribute decision making

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K型钢管混凝土节点疲劳性能试验研究

钟新谷,杨胜,石卫华

《中国工程科学》 2011年第13卷第9期页码 97-100

摘要：

以湘潭四大桥桁架拱为工程背景，进行了三种规格的K型钢管混凝土节点的疲劳试验，基于热点应力计算了K型钢管混凝土节点的疲劳荷载幅值，表明热点应力法能够较好地评估钢管混凝土节点的疲劳寿命；试验表明K型钢管混凝土节点的疲劳性能明显优于K型钢管节点。在此基础上初步提出了K型钢管混凝土节点的S—N曲线，对建立K型钢管混凝土节点疲劳寿命设计准则具有一定的参考意义。

关键词： K型钢管混凝土节点疲劳性能 S—N曲线

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Evaluation of the k-nearest neighbor method for forecasting the influent characteristics of wastewater

Minsoo KIM,Yejin KIM,Hyosoo KIM,Wenhua PIAO,Changwon KIM

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 299-310 doi: 10.1007/s11783-015-0825-7

摘要： The k-nearest neighbor (k-NN) method was evaluated to predict the influent flow rate and four water qualities, namely chemical oxygen demand (COD), suspended solid (SS), total nitrogen (T-N) and total phosphorus (T-P) at a wastewater treatment plant (WWTP). The search range and approach for determining the number of nearest neighbors (NNs) under dry and wet weather conditions were initially optimized based on the root mean square error (RMSE). The optimum search range for considering data size was one year. The square root-based (SR) approach was superior to the distance factor-based (DF) approach in determining the appropriate number of NNs. However, the results for both approaches varied slightly depending on the water quality and the weather conditions. The influent flow rate was accurately predicted within one standard deviation of measured values. Influent water qualities were well predicted with the mean absolute percentage error (MAPE) under both wet and dry weather conditions. For the seven-day prediction, the difference in predictive accuracy was less than 5% in dry weather conditions and slightly worse in wet weather conditions. Overall, the k-NN method was verified to be useful for predicting WWTP influent characteristics.

关键词： influent wastewater prediction data-driven model k-nearest neighbor method (k-NN)

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5G将带来哪些改变？

Erika K. Carlson

《工程（英文）》 2020年第6卷第7期页码 725-727 doi: 10.1016/j.eng.2020.05.012

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太空旅游离我们越来越近

Elizabeth K. Wilson

《工程（英文）》 2019年第5卷第5期页码 819-821 doi: 10.1016/j.eng.2019.08.006

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基于层次的K-means初始化算法

汤九斌,陆建峰,唐振民,杨静宇

《中国工程科学》 2007年第9卷第11期页码 74-79

摘要：

K-means算法是一种常用的聚类算法，但是聚类中心的初始化是其中的一个难点。笔者提出了一个基于层次思想的初始化方法。模拟数据和真实数据的实验结果均显示基于层次抽样初始化的K-means算法不仅收敛速度快、聚类质量高，而且对噪声不敏感，其性能明显优于现有的相关算法。

关键词：层次技术初始聚类中心加权数据 K平均聚类

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Hydrotreating of light gas oil using a NiMo catalyst supported on activated carbon produced from fluid petroleum coke

Rambabu,Sandeep Badoga,Kapil K. Soni,A.K. Dalai,J. Adjaye

《化学科学与工程前沿（英文）》 2014年第8卷第2期页码 161-170 doi: 10.1007/s11705-014-1430-1

摘要： Nitric acid functionalized steam activated carbon (NAFSAC) was prepared from waste fluid petroleum coke (FPC) and used as a support material for the synthesis of a NiMo catalyst (2.5 wt-% Ni and 13 wt-% Mo). The catalyst was then used for the hydrotreatment of light gas oil. The support and catalysts were characterized by Brunauer-Emmett-Teller (BET) gas adsorption method, X-ray diffraction, H -temperature programmed reduction, NH -temperature programmed desorption, CO-chemisorption, mass spetrography, scanning electron microscopy (SEM), Boehm titration, and Fourier transform infrared spectroscopy (FTIR). The SEM results showed that the carbon material retained a needle like structure after functionalization with HNO . The Boehm titration, FTIR, and BET results confirmed that the HNO functionalized material had moderate acidity, surface functional groups, and mesoporosity respectively. The produced NAFSAC had an inert nature, exhibited the sink effect and few metal support interactions, and contained functional groups. All of which make it a suitable support material for the preparation of a NiMo hydrotreating catalyst. Hydrotreating activity studies of the NiMo/NAFSAC catalyst were carried out under industrial operating conditions in a laboratory trickle bed reactor using coker light gas oil as the feedstock. A parallel study was performed on the hydrotreating activity of NiMo/ -Al O as a reference catalyst. The hydrodesulfurization and hydrodenitrogenation activities of the NiMo/NAFSAC catalyst were 62% and 30%, respectively.

关键词： activated carbon fluid petroleum coke NiMo catalyst hydrotreating light gas oil

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人工智能发明目前无法申请专利

Erika K. Carlson

《工程（英文）》 2020年第6卷第11期页码 1212-1213 doi: 10.1016/j.eng.2020.09.003

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Optimal design and development of PV-wind-battery based nano-grid system: A field-on-laboratory demonstration

TUDU, K. K. MANDAL, N. CHAKRABORTY

《能源前沿（英文）》 2019年第13卷第2期页码 269-283 doi: 10.1007/s11708-018-0573-z

摘要： The present paper has disseminated the design approach, project implementation, and economics of a nano-grid system. The deployment of the system is envisioned to acculturate the renewable technology into Indian society by field-on-laboratory demonstration (FOLD) and “bridge the gaps between research, development, and implementation.” The system consists of a solar photovoltaic (PV) (2.4 kWp), a wind turbine (3.2 kWp), and a battery bank (400 Ah). Initially, a prefeasibility study is conducted using the well-established HOMER (hybrid optimization model for electric renewable) software developed by the National Renewable Energy Laboratory (NREL), USA. The feasibility study indicates that the optimal capacity for the nano-grid system consists of a 2.16 kWp solar PV, a 3 kWp wind turbine, a 1.44 kW inverter, and a 24 kWh battery bank. The total net present cost (TNPC) and cost of energy (COE) of the system are US$20789.85 and US$0.673/kWh, respectively. However, the hybrid system consisting of a 2.4 kWp of solar PV, a 3.2 kWp of wind turbine, a 3 kVA of inverter, and a 400 Ah of battery bank has been installed due to unavailability of system components of desired values and to enhance the reliability of the system. The TNPC and COE of the system installed are found to be US$20073.63 and US$0.635/kWh, respectively and both costs are largely influenced by battery cost. Besides, this paper has illustrated the installation details of each component as well as of the system. Moreover, it has discussed the detailed cost breakup of the system. Furthermore, the performance of the system has been investigated and validated with the simulation results. It is observed that the power generated from the PV system is quite significant and is almost uniform over the year. Contrary to this, a trivial wind velocity prevails over the year apart from the month of April, May, and June, so does the power yield. This research demonstration provides a pathway for future planning of scaled-up hybrid energy systems or microgrid in this region of India or regions of similar topography.

关键词： photovoltaic (PV) wind battery nano-grid hybrid optimization model for electric renewable (HOMER) field-on-lab demonstration (FOLD)