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不同施肥配比对黔草4号鸭茅牧草产量的影响

畜牧与饲料科学 2015年第8期36卷 37-39页

作者：张月涛何静韩永芬方烁覃涛英贵州省德江县草地工作站贵州德江565200 贵州省草业研究所贵州贵阳550006

采用四元二次回归旋转组合设计方法,对氮、磷、钾、有机肥4个栽培因子对黔草4号鸭茅鲜草产量的影响进行研究。结果表明,对黔草4号鸭茅产量的影响以有机肥最大,其次为氮肥、磷肥,影响最小的是钾肥;当黔草4号鸭茅产草量达到高产目标5 100 ... 详细信息

采用四元二次回归旋转组合设计方法,对氮、磷、钾、有机肥4个栽培因子对黔草4号鸭茅鲜草产量的影响进行研究。结果表明,对黔草4号鸭茅产量的影响以有机肥最大,其次为氮肥、磷肥,影响最小的是钾肥;当黔草4号鸭茅产草量达到高产目标5 100 kg/667 m2时,要求每667 m2有机肥用量为3 000 kg、氮肥用量为30 kg、磷肥用量为20 kg、钾肥用量为20 kg。

关键词：黔草4号鸭茅施肥配比牧草产量

P型空肠袢代胃术对胃癌患者胃切除后消化道重建术后生存质量的影响

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中国医药导刊 2015年第10期17卷 997-999,1002页

作者：张曰涛陈秋楠田洪伟武警山东省总队医院普外科济南250013

目的：探讨P型空肠袢代胃术对胃癌患者胃切除后消化道重建术后生存质量的影响。方法：统计分析2012年5月-2014年5月我院收治的75例胃癌患者的临床资料。P型空肠袢代胃术组（P组,50例）和Lahey＋Braun吻合术组（L组,25例）。运用统计学软... 详细信息

目的：探讨P型空肠袢代胃术对胃癌患者胃切除后消化道重建术后生存质量的影响。方法：统计分析2012年5月-2014年5月我院收治的75例胃癌患者的临床资料。P型空肠袢代胃术组（P组,50例）和Lahey＋Braun吻合术组（L组,25例）。运用统计学软件SPSS21.0,分析不同手术方法两组患者的术中、术后情况,两组患者的机体恢复情况和两组患者的生存质量。分别用率和（x±s）表示计数资料和计量资料,用χ2和t检验组间比较。对上述数据进行统计学处理时检验水准α=0.05。结果：P组患者的手术时间（245.5±18.9）min较对照组短（261.6±20.5）min,（t=4.303,P〈0.05）,术中出血量明显比L组少（t=3.182,P〈0.05）;疼痛发生率、复发率、死亡率为8%（4/50）、2%（1/50）、6%（3/50）均明显比L组16%（4/25）、8%（2/50）、16%（4/25）低（P〈0.05）。两组差异均有统计学意义;P组患者进食量〉300g/d、进食次数〈5次/d的发生率84.0%（42/50）、64.0%（32/50）均明显比L组60.0%（15/25）、28.0%（7/25）高（χ2=11.14,12.83,P〈0.05）,体质量增加幅度明显比L组大（t=2.776,P〈0.05）,两组差异均有统计学意义;P组患者的并发症发生率10%（5/50）明显比L组20%（5/25）低（P〈0.05）,两组差异均有统计学意义;P组患者的活动能力、健康感受、生活感受、日常生活评分及Spitzer指数总分均明显比L组高（P〈0.05）,两组差异均有统计学意义;但两组患者的家庭支持评分之间的差异不显著（P〉0.05）。结论：P型空肠袢代胃术能够显著提升胃癌患者胃切除后消化道重建术后的生存质量。

关键词： P型空肠袢代胃术胃癌胃切除后消化道重建术生存质量影响

完全腹腔镜下左肝部分切除术与开放手术的效果比较

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中国医药导刊 2015年第6期17卷 556-558页

作者：陈秋楠张曰涛田洪伟武警山东省总队医院普外科济南250014

目的：比较完全腹腔镜下左肝部分切除术与开放手术的效果。方法：选取2012年5月~2014年5月我院收治的80例左肝肿瘤患者,依据手术方式将这些患者分为两组,即腹腔镜手术组（50例）和开放手术组（30例）,运用统计学软件SPSS21.0分析两组患... 详细信息

目的：比较完全腹腔镜下左肝部分切除术与开放手术的效果。方法：选取2012年5月~2014年5月我院收治的80例左肝肿瘤患者,依据手术方式将这些患者分为两组,即腹腔镜手术组（50例）和开放手术组（30例）,运用统计学软件SPSS21.0分析两组患者术中、术后情况、术后并发症、术前术后肝功能指标。分别用率和（x±s）表示计数资料和计量资料,然后分别用χ2和t检验组间比较,检验水准α=0.05。结果：腹腔镜手术组患者的术中出血量（176±59）ml明显比开放手术组（301±119）ml少（t=3.912,P〈0.05）,术后肛门排气时间和住院时间明显比开放手术组短（P〈0.05）,差异有统计学意义。两组患者的手术时间和住院费用之间的差异无统计学意义（P〉0.05）;腹腔镜手术组患者的术后并发症发生率4.0%（2/50）明显比开放手术组33.3%（10/30）低（χ2=5.059,P〈0.05）,差异有统计学意义;术前两组患者的肝功能指标之间的差异均不显著（P〉0.05）;术后1d、4d腹腔镜手术组患者的ALT明显比开放手术组低（t=2.592,P〈0.05）,ALB明显比开放手术组高（t=-7.262,P〈0.05）,差异有统计学意义。但两组患者的TBIL之间的差异均不显著（P〉0.05）。结论：完全腹腔镜下左肝部分切除术比开放手术的效果显著。

关键词：完全腹腔镜下左肝部分切除术开放手术效果比较

Blind adaptive identification and equalization using bias-compensated NLMS methods

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Science China(Information Sciences) 2022年第5期65卷 184-195页

作者： Zhen zhang Lijuan JIA Ran tao yue WANG School of Information and Electronics Beijing Institute of Technology

In this paper, two new blind adaptive identification and equalization algorithms based on second-order statistics are proposed. We consider a practical case where the noise statistics of each transmission channel is unknown. Resorting to the technique of antennas array, a single-input double-output channel can be obtained. We further convert the problem of blind identification into an errors-in-variables(EIV)parameter estimation problem, then we apply the normalized least-mean squares(NLMS) algorithms to tackle the problem. To improve the performance of the NLMS algorithms, we also develop a variable stepsize NLMS(VSS-NLMS) algorithm that ensures the stability of the algorithm and faster convergence speed at the beginning of the iterations process. Under various practical scenarios, noise affects transmission channels;it is necessary to estimate the variance and remove the bias. By modifying the cost function, we present a bias-compensated NLMS(BC-NLMS) algorithm and a bias-compensated NLMS algorithm with variable step-size(BC-VSS-NLMS) to eliminate the bias. The proposed algorithms estimate the variances of the noise online, and therefore, the noise-induced bias can be removed. The estimate of the channel characteristics is available for equalization. Simulation results are presented to demonstrate the performance of the proposed algorithms.

关键词： blind adaptive identification equalization normalized least mean squares algorithm bias compensation errors-in-variables

Dual-mode predictive control of a rotor suspension system

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Science China(Information Sciences) 2020年第1期63卷 178-189页

作者： yue WU Gui-Ping REN Hai-tao zhang Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and Technology State Key Laboratory of Digital Manufacturing Equipments and Technology

Rotor active magnetic bearing(rotor-AMB) systems are frequently used to alleviate vibrations for various applications such as in national defense, manufacturing industries, IC production, and aerospace engineering. One obstacle to improve machining efficiency and quality is the open-loop instability of rotorAMB systems during the machining process. We built a closed-loop processing platform using a spindle rotor installed with AMBs and thereby developed a rotor-AMB suspension system embedded with a dual-mode predictive controller(DMPC). The performance of the system is thus substantially improved. In the proposed DMPC, both model-based prediction and receding horizon optimization are utilized to guarantee the closedloop stability of the rotor-AMB suspension systems with input constraints. Finally, the effectiveness and superiority of the proposed method are examined through substantial levitation experiments on a machining platform with installed AMBs.

关键词： dual-mode predictive control system identification optimization control model predictive control suspension control

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Isobaric enzymatic assays reveal depth-dependent variation in microbial ectoenzyme activities in the deepest ocean on Earth

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Science China Earth Sciences 2025年第1期68卷 185-194页

作者： Junwei CAO Jiahua WANG Hongge zhang Junhao DENG Binbin PAN Jiawang CHEN Li zhang Jiasong FANG College of Oceanography and Ecological Science Shanghai Ocean University Ocean College Zhejiang University Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology

Microbial ectoenzymes play essential roles in the transformation and mineralization of organic matter in the ***, conventional methods for measuring microbial ectoenzyme activities(MEAs) in the deep ocean under atmospheric conditions can misrepresent the metabolic activities of indigenous microbial communities. To overcome this limitation, we measured the activities of three microbial ectoenzymes(aminopeptidase, α-glucosidase, and β-glucosidase) under both atmospheric and in situ pressure conditions in seawater collected using pressure-retaining and non-pressure-retaining samplers in the Challenger Deep, Mariana Trench. In the case of aminopeptidase and α-glucosidase, the highest isobaric MEAs were observed in the surface layer(50 m), followed by those at abyssopelagic depths(4,000–6,000 m) for aminopeptidase, hadal realm(10,903 m)for α-glucosidase, while β-glucosidase activity exhibited the highest value at 10,903 m. Furthermore, the isobaric MEAs in hadal waters were commonly found to be higher than the decompressed counterparts, highlighting the importance of pressure-retaining sampling and isobaric enzymatic assays. The half-saturation constant(Km) showed a general decreasing trend with depth,suggesting that the deep ocean microbes might have adapted to the high-pressure and oligotrophic environment by increasing their ectoenzyme's affinity to substrate. Furthermore, particle-free MEAs contribute more to the total MEAs in the deep ocean than particle-associated MEAs, suggesting the significance of cell-associated and dissolved ectoenzymes in ocean *** study provides a foundation for future investigations of MEAs in the ocean and has important implications for understanding the dynamics of microbially mediated biogeochemical cycling in marine ecosystems.

关键词： Pressure-retaining sampling Microbial ectoenzyme activity Deep-sea microbes High pressure Mariana Trench

Filterbank implementation for multi-channel sampling in fractional Fourier domain

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Science China(Technological Sciences) 2009年第9期52卷 2619-2628页

作者： zhang Feng tao Ran WANG yue Department of Electronic Engineering Beijing Institute of TechnologyBeijing100081China

Reconstruction of a continuous time signal from its periodic nonuniform samples and multi-channel samples is fundamental for multi-channel parallel A/D and MIMO systems. In this paper,with a filterbank interpretation of sampling schemes,the efficient interpolation and reconstruction methods for periodic nonuniform sampling and multi-channel sampling in the fractional Fourier domain are presented. Firstly,the interpolation and sampling identities in the fractional Fourier domain are derived by the properties of the fractional Fourier transform. Then,the particularly efficient filterbank implementations for the periodic nonuniform sampling and the multi-channel sampling in the fractional Fourier domain are introduced. At last,the relationship between the multi-channel sampling and the filterbank in the fractional Fourier domain is investigated,which shows that any perfect reconstruction filterbank can lead to new sampling and reconstruction strategies.

关键词： fractional Fourier transform filterbank interpolation identity

DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm

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Computers, Materials & Continua 2025年第1期82卷 645-674页

作者： Chunhui Li Xiaoying Wang Qingjie zhang Jiaye Liang Aijing zhang School of Information Engineering Institute of Disaster PreventionLangfang065201China Langfang Key Laboratory of Network Emergency Protection and Network Security Langfang065201China

Previous studies have shown that deep learning is very effective in detecting known ***,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low ***,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 *** hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 *** evaluation accuracy of the new dataset GINKS2023 created in this paper is *** to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score.

关键词： Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm