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饲料工业 2

WTO 1

养分消化与吸收 1

养殖业 1

内部分子结构 1

分子成像 1

分子营养 1

刚度 1

动物营养 1

北斗天线；宽带圆极化辐射；四端口顺序馈电网络；全球导航卫星系统（GNSS）接收机；卫星跟踪 1

双循环；粮食安全；粮食产能；绿色低碳；种养循环；新型蛋白饲料 1

双重作用 1

发展策略 1

变化高阶动态 1

同步辐射应用 1

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多黏菌素 1

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Identification of thermal error in a feed system based on multi-class LS-SVM

Chao JIN, Bo WU, Youmin HU, Yao CHENG

《机械工程前沿（英文）》 2012年第7卷第1期页码 47-54 doi: 10.1007/s11465-012-0307-6

摘要：

Research of thermal characteristics has been a key issue in the development of high-speed feed system. The thermal positioning error of a ball-screw is one of the most important objects to consider for high-accuracy and high-speed machine tools. The research work undertaken herein ultimately aims at the development of a comprehensive thermal error identification model with high accuracy and robust. Using multi-class least squares support vector machines (LS-SVM), the thermal positioning error of the feed system is identified with the variance and mean square value of the temperatures of supporting bearings and screw-nut as feature vector. A series of experiments were carried out on a self-made quasi high-speed feed system experimental bench HUST-FS-001 to verify the identification capacity of the presented method. The results show that the recommended model can be used to predict the thermal error of a feed system with good accuracy, which is better than the ordinary BP and RBF neural network. The work described in this paper lays a solid foundation of thermal error prediction and compensation in a feed system.

关键词： least squares support vector machine (LS-SVM) feed system thermal error precision machining

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A deep feed-forward neural network for damage detection in functionally graded carbon nanotube-reinforced

《结构与土木工程前沿（英文）》 2021年第15卷第6期页码 1453-1479 doi: 10.1007/s11709-021-0767-z

摘要： This paper proposes a new Deep Feed-forward Neural Network (DFNN) approach for damage detection in functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates. In the proposed approach, the DFNN model is developed based on a data set containing 20 000 samples of damage scenarios, obtained via finite element (FE) simulation, of the FG-CNTRC plates. The elemental modal kinetic energy (MKE) values, calculated from natural frequencies and translational nodal displacements of the structures, are utilized as input of the DFNN model while the damage locations and corresponding severities are considered as output. The state-of-the art Exponential Linear Units (ELU) activation function and the Adamax algorithm are employed to train the DFNN model. Additionally, in order to enhance the performance of the DFNN model, the mini-batch and early-stopping techniques are applied to the training process. A trial-and-error procedure is implemented to determine suitable parameters of the network such as the number of hidden layers and the number of neurons in each layer. The accuracy and capability of the proposed DFNN model are illustrated through two distinct configurations of the CNT-fibers constituting the FG-CNTRC plates including uniform distribution (UD) and functionally graded-V distribution (FG-VD). Furthermore, the performance and stability of the DFNN model with the consideration of noise effects on the input data are also investigated. Obtained results indicate that the proposed DFNN model is able to give sufficiently accurate damage detection outcomes for the FG-CNTRC plates for both cases of noise-free and noise-influenced data.

关键词： damage detection deep feed-forward neural networks functionally graded carbon nanotube-reinforced composite plates modal kinetic energy

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INTERCROPPING: FEED MORE PEOPLE AND BUILD MORE SUSTAINABLE AGROECOSYSTEMS

《农业科学与工程前沿（英文）》 2021年第8卷第3期页码 373-386 doi: 10.15302/J-FASE -2021398

摘要：

Intercropping is a traditional farming system that increases crop diversity to strengthen agroecosystem functions while decreasing chemical inputs and minimizing negative environmental effects of crop production. Intercropping is currently considerable interest because of its importance in sustainable agriculture. Here, we synthesize the factors that make intercropping a sustainable means of food production by integrating biodiversity of natural ecosystems and crop diversity. In addition to well-known yield increases, intercropping can also increase yield stability over the long term and increase systemic resistance to plant diseases, pests and other unfavorable factors (e.g. nutrient deficiencies). The efficient use of resources can save mineral fertilizer inputs, reduce environmental pollution risks and greenhouse gas emissions caused by agriculture, thus mitigating global climate change. Intercropping potentially increases above- and below-ground biodiversity of various taxa at field scale, consequently it enhances ecosystem services. Complementarity and selection effects allow a better understanding the mechanisms behind enhanced ecosystem functioning. The development of mechanization is essential for large-scale application of intercropping. Agroecosystem multifunctionality and soil health should be priority topics in future research on intercropping.

关键词： agroecosystems ， crop diversity ，intercropping，interspecific interactions，sustainable agriculture

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Practical consideration for design and optimization of the step feed process

Shijian GE, Yongzhen PENG, Congcong LU, Shuying WANG

《环境科学与工程前沿（英文）》 2013年第7卷第1期页码 135-142 doi: 10.1007/s11783-012-0454-3

摘要： Based on the anoxic/oxic (A/O) step feed process, a modified University of Cape Town (UCT) step feed process was developed by adding an anaerobic zone and adjusting sludge return pipeline. Performance evaluation of these two types of processes was investigated by optimizing operational parameters, such as the anaerobic/anoxic/oxic volumes, internal recycle ratios, and sludge retention times, for removal of chemical oxygen demanding (COD), nitrogen, and phosphorus. Results showed high removal efficiencies of COD of (85.0±1.7)%, ammonium of (99.7±0.2)%, total nitrogen (TN) of (85.5±1.7)%, phosphorus of (95.1±3.3)%, as well as excellent sludge settleability with average sludge volume index of (83.7±9.5) L·mg in the modified UCT process. Moreover, (61.5±6.0)% of influent COD was efficiently involved in denitrification or phosphorus release process. As much as 35.3% of TN was eliminated through simultaneous nitrification and denitrification process in aerobic zones. In addition, the presence of denitrifying phosphorus accumulating organisms (DNPAOs), accounting for approximately 39.2% of PAOs, was also greatly beneficial to the nitrogen and phosphorus removal. Consequently, the modified UCT step feed process was more attractive for the wastewater treatment plant, because it had extremely competitive advantages such as higher nutrient removal efficiencies, lower energy and dosages consumption, excellent settling sludge and operational assurance.

关键词： step feed anoxic/oxic (A/O) University of Cape Town (UCT) simultaneous nitrification and denitrification (SND) denitrifying phosphorus removal biological nutrient removal (BNR)

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FBRM and PVM investigations of the double feed semi-batch crystallization of 6-aminopenicillanic acid

Min SU, Lin WANG, Hua SUN, Jingkang WANG

《化学科学与工程前沿（英文）》 2009年第3卷第3期页码 282-288 doi: 10.1007/s11705-009-0018-7

摘要： 6-Aminopenicillanic acid (6-APA) is a crucial pharmaceutical intermediate in the chemistry of semi-synthetic antibiotics. The focused beam reflectance measurement (FBRM) technology and particle vision measurement (PVM) technology were employed to the processes of online-monitoring of 6-APA crystallization behavior in a double-feeding semi-batch crystallizer. Experiments were carried out with four kinds of double-feeding policies and the results were compared with the traditional single-feeding. Records and analysis of FBRM indicated that the nucleation of double feeding policy was much higher than single policy, and chord length of 6-APA was almost determined and had little change after the nucleation peak. Ostwald ripening process had no significant effect on further growth of 6-APA crystal. PVM images showed that the crystal habit of 6-APA was continuously changed during the crystallization process. The development of (002) face in the final crystal for the five feeding policies were different.

关键词： 6-aminopenicillanic acid crystallization double-feeding FBRM PVM crystal habit

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Comments on “Adaptation of Chinese and German maize-based food-feed-energy systems to limited phosphate

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《农业科学与工程前沿（英文）》 2019年第6卷第4期页码 443-444 doi: 10.15302/J-FASE-2019288

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论我国饲料工业的标准化工作及其产品的质量管理

张子仪

《中国工程科学》 2001年第3卷第7期页码 30-36

摘要：

上个世纪末，我国饲料工业总产量比改革开放前增长了近70倍。1999年全国配合饲料合格率也从20世纪80年代的40%～60%提高到95.7%，这是一个巨大的成就。但目前饲料工业标准化工作则相对滞后。入世以后，我国饲料工业标准化体系将面临着与国际质量管理和质量保证标准的接轨以及与环境管理系列标准的配套问题。为此，在近期内应把握时机，及时作好我国饲料工业标准化工作水平的提高及更新换代。当前应重点抓紧饲料安全性标准的增删与修订。对饲料卫生标准、饲料原料标准、饲料质量监测技术及生物学效价评定等方面的标准必须全国统一；而对饲养标准则应因地制宜分类设置，根据具体情况可以跨省区设一类饲养标准，也可以在一个省或区设多种类型的饲养标准。

当前，饲料市场各个流通环节中的法制建设任务仍然十分艰巨。要坚决杜绝一切有损社会、生态效益的饲料添加剂进入市场；特别要严密监视国外活菌制剂类饲料及一切激素类饲料添加剂非法进入我国市场。要加强保护我国目前尚保留着的大面积净土；要为合法的、科学的饲料添加剂正名。这是争创“中国产绿色产品”品牌，提高我国饲料工业产品市场竞争能力的重要保证。

关键词：饲料工业标准化工作安全性国际环境管理系列标准饲养标准

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Denitrification and phosphorus uptake by DPAOs using nitrite as an electron acceptor by step-feed strategies

Bin MA, Shuying WANG, Guibing ZHU, Shijian GE, Junmin WANG, Nanqi Ren, Yongzhen PENG

《环境科学与工程前沿（英文）》 2013年第7卷第2期页码 267-272 doi: 10.1007/s11783-012-0439-2

摘要： Denitrifying phosphorus accumulating organisms (DPAOs) using nitrite as an electron acceptor can reduce more energy. However, nitrite has been reported to have an inhibition on denitrifying phosphorus removal. In this study, the step-feed strategy was proposed to achieve low nitrite concentration, which can avoid or relieve nitrite inhibition. The results showed that denitrification rate, phosphorus uptake rate and the ratio of the phosphorus uptaken to nitrite denitrified (anoxic P/N ratio) increased when the nitrite concentration was 15 mg·L after step-feeding nitrite. The maximum denitrification rate and phosphorus uptake rate was 12.73 mg and 18.75 mg , respectively. These rates were higher than that using nitrate (15 mg·L ) as an electron acceptor. The maximum anoxic P/N ratio was 1.55 mg . When the nitrite concentration increased from 15 to 20 mg after addition of nitrite, the anoxic phosphorus uptake was inhibited by 64.85%, and the denitrification by DPAOs was inhibited by 61.25%. Denitrification rate by DPAOs decreased gradually when nitrite (about 20 mg·L ) was added in the step-feed SBR. These results indicated that the step-feed strategy can be used to achieve denitrifying phosphorus removal using nitrite as an electron acceptor, and nitrite concentration should be maintained at low level (<15 mg·L in this study).

关键词： denitrifying phosphate accumulating organisms (DPAOs) denitrification phosphorus uptake nitrite step-feed enhanced biological phosphorus removal

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中国动物营养和饲料科学的发展史

李德发

《工程（英文）》 2017年第3卷第5期 doi: 10.1016/J.ENG.2017.05.026

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Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Xiang ZHANG, Zhichao CHEN

《能源前沿（英文）》 2013年第7卷第3期页码 406-412 doi: 10.1007/s11708-013-0266-6

摘要： To reduce oil consumption during firing-up and partial-load operation, a tiny-oil ignition burner has been recommended. Through reacting-flow experiments performed on a full-scale experimental setup, the influence of different oil flow rates on bituminous coal combustion as well as flow rates without coal feed was analyzed. The ignition burner is identical to that normally used in an 800 MWe utility boiler. Under operating conditions with flow rates of 50, 100, and 150 kg/h, gas temperature distributions were measured in the burner. At the equivalent measuring points at the exits of the first and second combustion chambers, these distributions remained almost unchanged under a constant coal feed rate of 4 t/h. However on the burner centerline, distributions increased slightly with increasing flow rate. Different gas concentrations were measured at the center of the burner exit. For instance, the O concentration at the burner exit varied from 0.01% to 0.31% whereas CO concentrations were more than 10000 ppm. At the same coal feed rate of 4 t/h, burner resistances are 480, 600, and 740 Pa for oil flow rates of 50, 100, and 150 kg/h, respectively.

关键词： ignition coal burner boiler oil flow rate

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论我国饲料工业入关前后面临的挑战

张子仪

《中国工程科学》 1999年第1卷第1期页码 88-93

摘要：

改革开放以来，我国肉、蛋、奶总产量比70年代末期增长了6～8倍，1998年饲料工业的产品产量已达到了8568万t，比70年代后期高出80多倍；我国饲料工业在进入WTO前后将面临着市场竞争的压力；中长期内我国饲料蛋白质资源大约缺口一半，入关后，优质廉价的进口添加剂及饲料用农产品将对我国饲料市场形成冲击。

建立健全具有中国特色的饲料工业生产体系，认真贯彻《饲料和饲料添加剂管理条例》至关重要；知识经济实质上是信息经济，尽快联合起来加速中国饲料工业信息网的建设，提高决策水平，才能有备无患地迎战入关前后可能遇到的种种冲击。

关键词：饲料工业 WTO 养殖业

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水产养殖动物营养与饲料工程发展战略研究

解绶启,张文兵,韩冬,麦康森

《中国工程科学》 2016年第18卷第3期页码 29-36 doi: 10.15302/J-SSCAE-2016.03.005

摘要：

本文综述了我国水产养殖动物营养学研究和饲料工程方面近期的研究，分析了产业发展的问题，探讨了下一步的政策措施。可以发现，过去10多年里，水产动物营养与饲料的发展在营养素需求、动物的摄食与投喂、仔稚鱼饲料、亲本营养、添加剂等方面取得了重要的进展，但仍然存在饵料系数高、环境排放大、饲料成本高、效益不稳定等问题。下一步的研究应该以“安全高效，节约环保”为目标，引入生态学和现代组学理念，开展水产动物营养代谢的分子机理、动物的营养需要与精准饲料配方技术、饲料质量控制与加工工艺、精准投喂技术、品质调控技术等方面的研究，同时在政策上应该扩大学科交流、实行长期稳定支持等。

关键词：水产养殖动物营养饲料发展策略

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Implementation of an adaptive feed speed 3D NURBS interpolation algorithm

LIANG Hong-bin, WANG Yong-zhang, LI Xia

《机械工程前沿（英文）》 2006年第1卷第4期页码 403-408 doi: 10.1007/s11465-006-0047-6

摘要： NURBS (non-uniform rational B-spline) interpolation algorithms have been provided in modern CNC (computer numerical control) systems. However, most of them focus on a constant feed speed without considering the contour accuracy. In order to deal with this problem, an adaptive feed speed interpolation algorithm for 3D NURBS parametric curves with confined chord errors is proposed. When the instantaneous radius of the curvature is small enough, the proposed interpolation algorithm automatically reduces the feed speed to meet the specified chord error. In the other situation it uses the second-order Taylor s expansions approximation interpolation algorithm to obtain a constant feed speed so that the contour accuracy in the CNC system is guaranteed. Experimental results were provided to verify the feasibility and precision of the proposed interpolation algorithm.

关键词： NURBS parametric rational B-spline second-order non-uniform rational precision

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动物营养和饲料科学

Adrian R. Egan

《工程（英文）》 2017年第3卷第5期页码 586-587 doi: 10.1016/J.ENG.2017.05.025

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动态变化滚珠丝杠进给系统的智能非同位控制策略

刘辉, 张俊, 赵万华

《工程（英文）》 2017年第3卷第5期页码 641-647 doi: 10.1016/J.ENG.2017.04.007

摘要：

滚珠丝杠进给驱动系统由于其细长的螺旋主轴和部件之间连接部分的灵活性，具有变化的高阶动态特性，并且当采用直线光栅尺进行直接位置测量时，它还具有非同位控制的明显特征。长期以来，动态特性和非同位状况一直是运动和振动控制困难的根源，它们还会降低轴的运动精度。在本研究中，考虑到灵活性及其变化，我们建立了基于频率的子结构动态模型，并充分研究了动态特性对位置变化的依赖，开发出由模态特征修正器（MCM）和智能自适应调整算法（ATA）组成的控制策略。MCM 由峰值滤波器和陷波滤波器组成，从而将设备动态变为虚拟同位系统，且可以避免控制溢出。使用人工神经网络（ANN）作为平滑参数插值器，可以实时更新滤波器的参数，以便应对进给驱动系统的动态变化。我们已经在实际的进给驱动系统中验证了所提出策略的有效性和鲁棒性。

关键词：滚珠丝杠进给驱动系统变化高阶动态非同位控制模态特征修正器智能自适应调整算法