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基于改进动麦优化模糊C-均值的WSN分簇信誉路由算法
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作者 韩冰青 温锦笑 《计算机应用研究》 北大核心 2026年第1期240-246,共7页
针对无线传感器网络中分簇不均、节点能耗高及路由安全性低等问题,提出一种基于改进动麦优化模糊C-means的WSN分簇信誉路由算法(IFCAOR)。首先利用改进的动麦算法优化模糊C-means算法的初始聚类中心,提高网络分簇效果。其次,在簇首选举... 针对无线传感器网络中分簇不均、节点能耗高及路由安全性低等问题,提出一种基于改进动麦优化模糊C-means的WSN分簇信誉路由算法(IFCAOR)。首先利用改进的动麦算法优化模糊C-means算法的初始聚类中心,提高网络分簇效果。其次,在簇首选举阶段,综合节点能量、距离等因素,动态选择簇首,实现负载均衡。最后,在数据传输阶段,采用单多跳轮询机制,并结合中继节点的负载、信誉值和路径衰减等构建路由适应度函数,利用改进动麦算法规划高效安全的传输路由,降低节点能耗并提高路由安全性。仿真结果表明,IFCAOR算法的网络生命周期较LEACH、IFCRA和HMABFOA分别提升93%、49.6%和34.3%,IFCAOR算法能有效平衡网络负载,延长网络生命周期。 展开更多
关键词 无线传感器网络 模糊c-均值 动麦优化算法 分簇路由 能耗均衡
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C/N复合诱导对硫酸盐还原菌(SRB)EPS的显著影响:空间分布、化学组成、Cu(Ⅱ)吸附性能及其机制
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作者 郑广文 宋卫锋 +8 位作者 杨佐毅 涂传英 周克勤 边俊铭 彭景峰 袁槟 李圣乐 张祥丹 白晓燕 《环境科学学报》 北大核心 2026年第1期36-50,共15页
胞外聚合物(EPS)能够有效吸附重金属并降低其环境毒性.LB(Loosely-Bound)-EPS和TB(Tightly-Bound)-EPS在吸附过程中表现出不同的作用.本研究探讨了梯度C/N体系对Desulfovibrio desulfuricans subsp.desulfuricans的诱导效应,分析了LB-EP... 胞外聚合物(EPS)能够有效吸附重金属并降低其环境毒性.LB(Loosely-Bound)-EPS和TB(Tightly-Bound)-EPS在吸附过程中表现出不同的作用.本研究探讨了梯度C/N体系对Desulfovibrio desulfuricans subsp.desulfuricans的诱导效应,分析了LB-EPS和TB-EPS在不同C/N条件下的组成及其对Cu(Ⅱ)的吸附性能.在最佳条件诱导(C/N=5)下,TB-EPS和LB-EPS的产量相比对照组分别增加了151.08%和170.03%;其中,LB-EPS以多糖为主,而TB-EPS则以蛋白质为主,TB-EPS的Cu(Ⅱ)吸附能力优于LB-EPS.吸附过程符合Langmuir等温模型,理论最大吸附量分别为1447.51 mg·g^(-1)和2232.30 mg·g^(-1),并遵循准二级动力学模型.FTIR、XPS和3D-EEM分析表明,诱导处理增强了EPS中蛋白类物质及其官能团的含量.XPS分析显示EPS化学组成发生显著变化,LB-EPS中C=O和C-O/C-N基团分别增加了67.19%和27.23%,TB-EPS中分别增加了53.19%和37.50%.诱导后,两种EPS中的酸性氨基酸(Asp和Glu)显著增加,且TB-EPS含量更高、提升更显著,为Cu(Ⅱ)提供了丰富的结合位点.以上所有定量数据和表征结果均表明,TB-EPS相较于LB-EPS具有更优的吸附性能.本研究为重金属污染废水治理提供了理论基础,并阐明了SRB的EPS的空间结构及功能机制. 展开更多
关键词 c/n诱导 LB-EPS TB-EPS 生物吸附 SRB
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Optimizing crop yields while minimizing environmental impact through deep placement of nitrogen fertilizer
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作者 Lingxiao Zhu Hongchun Sun +8 位作者 Liantao Liu Ke Zhang Yongjiang Zhang Anchang Li Zhiying Bai Guiyan Wang Xiaoqing Liu Hezhong Dong Cundong Li 《Journal of Integrative Agriculture》 2025年第1期36-60,共25页
Nitrogen(N)serves as an essential nutrient for yield formation across diverse crop types.However,agricultural production encounters numerous challenges,notably high N fertilizer rates coupled with low N use efficiency... Nitrogen(N)serves as an essential nutrient for yield formation across diverse crop types.However,agricultural production encounters numerous challenges,notably high N fertilizer rates coupled with low N use efficiency and serious environmental pollution.Deep placement of nitrogen fertilizer(DPNF)is an agronomic measure that shows promise in addressing these issues.This review aims to offer a comprehensive understanding of DPNF,beginning with a succinct overview of its development and methodologies for implementation.Subsequently,the optimal fertilization depth and influencing factors for different crops are analyzed and discussed.Additionally,it investigates the regulation and mechanism underlying the DPNF on crop development,yield,N use efficiency and greenhouse gas emissions.Finally,the review delineates the limitations and challenges of this technology and provides suggestions for its improvement and application.This review provides valuable insight and reference for the promotion and adoption of DPNF in agricultural practice. 展开更多
关键词 deep placement of n fertilizer optimal fertilization depth YIELD n use efficiency greenhouse gas emissions
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Game theory approach to optimal capital cost allocation in pollution control 被引量:8
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作者 Chen Wen ying Institute of Nuclear Energy Technology, Tsinghua University, Beijing 100084,China Hou Dun Urban Water Resources Center, Ministry of Construction, Beijing 100007,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期104-110,共7页
This paper tries to integrate game theory, a very useful tool to resolve conflict phenomena, with optimal capital cost allocation issue in total emission control. First the necessity of allocating optimal capital cos... This paper tries to integrate game theory, a very useful tool to resolve conflict phenomena, with optimal capital cost allocation issue in total emission control. First the necessity of allocating optimal capital costs fairly and reasonably among polluters in total emission control was analyzed. Then the possibility of applying game theory to the issue of the optimal capital cost allocation was expounded. Next the cooperative N person game model of the optimal capital cost allocation and its solution ways including method based on Shapley value, least core method, weak least core methods, proportional least core method, CGA method, MCRS method and so on were delineated. Finally through application of these methods it was concluded that to apply game theory in the optimal capital cost allocation issue is helpful to implement the total emission control planning schemes successfully, to control pollution effectively, and to ensure sustainable development. 展开更多
关键词 total emission control optimal capital cost allocation game theory cooperative n person game model.
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Long-term integrated agronomic optimization maximizes soil quality and synergistically improves wheat yield and nitrogen use efficiency
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作者 Xinhu Guo Jinpeng Chu +4 位作者 Yifan Hua Yuanjie Dong Feina Zheng Mingrong He Xinglong Dai 《Journal of Integrative Agriculture》 2025年第8期2940-2953,共14页
Integrated agronomic optimization(IAO)adopts suitable crop varieties,sowing dates,planting density,and advanced nutrient management to redesign the entire production system according to the local environment,and it ca... Integrated agronomic optimization(IAO)adopts suitable crop varieties,sowing dates,planting density,and advanced nutrient management to redesign the entire production system according to the local environment,and it can achieve synergistic improvements in crop yields and resource utilization.However,the intensity and magnitude of the impacts of IAO on soil quality under long-term intensive production and high nitrogen use efficiency(NUE)require further clarification.Based on a 13-year field experiment conducted in Dawenkou,Tai'an,Shadong Province,China,we investigated the effects of four cultivation modes on the grain yield,NUE,and soil aggregate structure,as well as the fraction of organic matter(SOM)and soil quality,reflected by the integrated fertility index(IFI),during the winter wheat maturation periods in 2020–2022.The four cultivation modes were traditional local farming(T1),farmer-based improvement(T2),increased yield regardless of production cost(T3),and integrated soil–crop system management(T4).As the IAO modes,T2 and T4 were characterized by denser planting,reduced nitrogen(N)fertilizer application rates,and delayed sowing compared to T1 and T3,respectively.In this long-term experiment,IAO was found to maintain aggregate stability,increase SOM content(by increasing organic carbon and total nitrogen of the light fraction(LF)and the particulate organic matter fraction(POM)),and improve SOM quality(by increasing the proportions of LF and POM and the ratio of organic carbon to total nitrogen in SOM).Compared to T1,the IFI values of T2,T3,and T4 increased by 10.91,23.38,and 25.55%,and by 17.78,6.41,and 28.94%in the 0–20 and 20–40 cm soil layers,respectively.The grain yield of T4 was 22.52%higher than that of T1,and reached 95.98%of that in T3.Furthermore,the NUE of T4 was 35.61%higher than those of T1 and T3.In conclusion,our results suggest that the IAO mode T4 synergistically increases grain yield and NUE in winter wheat,while maximizing soil quality. 展开更多
关键词 soil aggregates SOM fraction soil c:n soil quality winter wheat
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Diurnal Variation of Soil CO2 Efflux and Its Optimal Measuring Time-window of Temperate Meadow Steppes in Western Songnen Plain, China 被引量:2
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作者 YU Xiuli LI Xiujun +4 位作者 XU Linshu WANG Ming ZHANG Jitao JIANG Ming WANG Guodong 《Chinese Geographical Science》 SCIE CSCD 2016年第4期518-526,共9页
In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux s... In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux system under five typical plant communi- ties (Suaeda glauca (Sg), Chloris virgata (Cv), Puecinellia distans (Pd), Leymus chinensis (Lc) and Phragmites australis (Pa)) and an alkali-spot land (As) at the meadow steppe of western Songnen Plain. The results showed that the diurnal variation of soil CO2 effiux exhibited a single peak curve in the growing season. Diurnal maximum soil respiration (Rs) often appeared between 1 1:00 and 13:00, while the minimum occurred at 21:00-23:00 or before dawn. Air temperature near the soil surface (Ta) and soil temperature at 10 cm depth (Tlo) exerted dominant control on the diurnal variations of soil respiration. The time-windows 7:00-9:00 could be used as the optimal measuring time to represent the daily mean soil CO2 effiux at the Cv, Pd, Lc and Pa sites. The daily mean soil CO2 effiux was close to the soil COz effiux from 15:00 to 17:00 and the mean of 2 individual soil CO2 effiux from 15:00 to 19:00 at the As and Sg sites, respectively. During nocturnal hours, negative soil CO2 fluxes (CO2 downwards into the soil) were frequently observed at the As and Sg sites, the magnitude of the negative CO2 fluxes were 0.10-1.55 gmol/(m2.s) and 0.10-0.69 gmol/(m2.s)at the two sites. The results im- plied that alkaline soils could absorb CO2 under natural condition, which might have significant implications to the global carbon budget accounting. 展开更多
关键词 soil respiration cQ effiux meadow steppe optimal measurement time negative c02 effiux
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Optimal activated carbon for separation of CO_2 from(H_2 + CO_2) gas mixture 被引量:1
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作者 Xiao-Xin Zhang Peng Xiao +5 位作者 Chang-Yu Sun Gen-Xiang Luo Jia Ju Xiao-Rong wang Hao-Xuan wang Hao Yang 《Petroleum Science》 SCIE CAS CSCD 2018年第3期625-633,共9页
Seven types of activated carbon were used to investigate the effect of their structure on separation of CO2 from(H2 + CO2) gas mixture by the adsorption method at ambient temperature and higher pressures. The resul... Seven types of activated carbon were used to investigate the effect of their structure on separation of CO2 from(H2 + CO2) gas mixture by the adsorption method at ambient temperature and higher pressures. The results showed that the limiting factors for separation of CO2 from 53.6 mol% H2 + 46.4 mol% CO2 mixture and from 85.1 mol% H2 + 14.9 mol% CO2 mixture were different at 20 °C and about 2 MPa. The best separation result could be achieved when the pore diameter of the activated carbon ranged from 0.77 to 1.20 nm, and the median particle size was about2.07 lm for 53.6 mol% H2 + 46.4 mol% CO2 mixture and 1.41 lm for 85.1 mol% H2 + 14.9 mol% CO2 mixture. The effect of specific area and pore diameter of activated carbon on separation CO2 from 53.6 mol% H2 + 46.4 mol% CO2 mixture was more significant than that from 85.1 mol% H2 + 14.9 mol% CO2 mixture. CO2 in the gas phase can be decreased from 46.4 mol% to 2.3 mol%–4.3 mol% with a two-stage separation process. 展开更多
关键词 Structure of activated carbon characteristic optimization SEPARATIOn H2 c02 mixtures
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Optimal Routing with Spatial-Temporal Dependencies for Traffic Flow Control in Intelligent Transportation Systems 被引量:1
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作者 R.B.Sarooraj S.Prayla Shyry 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2071-2084,共14页
In Intelligent Transportation Systems(ITS),controlling the trafficflow of a region in a city is the major challenge.Particularly,allocation of the traffic-free route to the taxi drivers during peak hours is one of the ch... In Intelligent Transportation Systems(ITS),controlling the trafficflow of a region in a city is the major challenge.Particularly,allocation of the traffic-free route to the taxi drivers during peak hours is one of the challenges to control the trafficflow.So,in this paper,the route between the taxi driver and pickup location or hotspot with the spatial-temporal dependencies is optimized.Initially,the hotspots in a region are clustered using the density-based spatial clustering of applications with noise(DBSCAN)algorithm tofind the hot spots at the peak hours in an urban area.Then,the optimal route is allocated to the taxi driver to pick up the customer in the hotspot.Before allocating the optimal route,each route between the taxi driver and the hot spot is mapped to the number of taxi drivers.Among the map function,the optimal map is selected using the rain opti-mization algorithm(ROA).If more than one map function is obtained as the opti-mal solution,the map between the route and the taxi driver who has done the least number of trips in the day is chosen as thefinal solution This optimal route selec-tion leads to control of the trafficflow at peak hours.Evaluation of the approach depicts that the proposed trafficflow control scheme reduces traveling time,wait-ing time,fuel consumption,and emission. 展开更多
关键词 Intelligent transportation system(ITS) DBScAn rain optimization algorithm(ROA) trafficflow control
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Soft-sensing modeling and intelligent optimal control strategy for distillation yield rate of atmospheric distillation oil refining process 被引量:2
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作者 Zheng Wang Cheng Shao Li Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1113-1124,共12页
It is a challenge to conserve energy for the large-scale petrochemical enterprises due to complex production process and energy diversification. As critical energy consumption equipment of atmospheric distillation oil... It is a challenge to conserve energy for the large-scale petrochemical enterprises due to complex production process and energy diversification. As critical energy consumption equipment of atmospheric distillation oil refining process, the atmospheric distillation column is paid more attention to save energy. In this paper, the optimal problem of energy utilization efficiency of the atmospheric distillation column is solved by defining a new energy efficiency indicator - the distillation yield rate of unit energy consumption from the perspective of material flow and energy flow, and a soft-sensing model for this new energy efficiency indicator with respect to the multiple working conditions and intelligent optimizing control strategy are suggested for both increasing distillation yield and decreasing energy consumption in oil refining process. It is found that the energy utilization efficiency level of the atmospheric distillation column depends closely on the typical working conditions of the oil refining process, which result by changing the outlet temperature, the overhead temperature, and the bottom liquid level of the atmospheric pressure tower. The fuzzy C-means algorithm is used to classify the typical operation conditions of atmospheric distillation in oil refining process. Furthermore, the LSSVM method optimized with the improved particle swarm optimization is used to model the distillation rate of unit energy consumption. Then online optimization of oil refining process is realized by optimizing the outlet temperature, the overhead temperature with IPSO again. Simulation comparative analyses are made by empirical data to verify the effectiveness of the proposed solution. 展开更多
关键词 Energy efficiency optimIZATIOn cRUDE oil DISTILLATIOn Particle WARM optimIZATIOn Fuzzy c-MEAnS algorithm Working condition
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Optimal design of hot rolling process for C-Mn steel by combining industrial data-driven model and multi-objective optimization algorithm 被引量:7
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作者 Si-wei Wu Xiao-guang Zhou +3 位作者 Jia-kuang Ren Guang-ming Cao Zhen-yu Liu Nai-an Shi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第7期700-705,共6页
A successful mechanical property data-driven prediction model is the core of the optimal design of hot rolling process for hot-rolled strips. However, the original industrial data, usually unbalanced, are inevitably m... A successful mechanical property data-driven prediction model is the core of the optimal design of hot rolling process for hot-rolled strips. However, the original industrial data, usually unbalanced, are inevitably mixed with fluctuant and abnormal values. Models established on the basis of the data without data processing can cause misleading results, which cannot be used for the optimal design of hot rolling process. Thus, a method of industrial data processing of C-Mn steel was proposed based on the data analysis. The Bayesian neural network was employed to establish the reliable mechanical property prediction models for the optimal design of hot rolling process. By using the multi-objective optimization algorithm and considering the individual requirements of costumers and the constraints of the equipment, the optimal design of hot rolling process was successfully applied to the rolling process design for Q345B steel with 0.017% Nb and 0.046% Ti content removed. The optimal process design results were in good agreement with the industrial trials results, which verify the effectiveness of the optimal design of hot rolling process. 展开更多
关键词 Industrial data Data processing - Mechanical property optimal design Hot rolling process c-Mn steel
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A rate-based method for dynamic analysis and optimal design of reactive extraction: n-Hexyl acetate esterification as an example 被引量:1
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作者 Xutao Hu Hao Qin +3 位作者 Biao Hu Hongye Cheng Lifang Chen Zhiwen Qi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期76-83,共8页
The dynamic analysis and optimal design of reactive extraction are challenging due to high nonlinearity of model equations and tough decision of judging criteria. In this work, a dynamic rate-based method is developed... The dynamic analysis and optimal design of reactive extraction are challenging due to high nonlinearity of model equations and tough decision of judging criteria. In this work, a dynamic rate-based method is developed on g PROMS platform to get easy access to the solutions of reactive extraction with phase splitting. Based on rigorous criteria, dynamic analysis from initial state to final equilibrium(e.g., evolution of phase composition, mass transfer rate and reaction rate) and optimal design of operating conditions(e.g., extractant dosage and feed molar ratio) are achieved. To illustrate the method, the esterification of n-hexyl acetate is taken as an example. The approach proves to be reliable in the analysis and optimization of the exemplified system, which provides instructive reference for further process design and simulation of reactive extraction. 展开更多
关键词 REAcTIVE extraction Dynamic rate-based method optimal design Process simulation n-Hexyl AcETATE ESTERIFIcATIOn
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新型倒置A^(2)/O耦联MBR组合工艺处理农村低C/N废水的研究 被引量:1
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作者 韩卫萍 盖磊 《水处理技术》 CAS 北大核心 2025年第1期114-119,共6页
针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OL... 针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OLR由150 mg/L提高至450 mg/L时,总氮(TN)和溶解性磷酸盐(SOP)去除率分别由67.6%和86.6%提高至72.4%和94.3%,进一步提高OLR降低了组合工艺对污染物和营养盐的去除。此外,OLR能影响新工艺内污泥特征,提高OLR促进了胞外聚合物(EPS)分泌,尤其在OLR为600 mg/L组别内,EPS含量提高至139.6 mg/g。进水OLR对缺氧池内EPS的影响要大于其对厌氧池内EPS的影响。OLR能影响新工艺内污染物和营养盐去除相关关键酶的活性,当OLR为450 mg/L时,污染物和营养盐去除相关关键活性酶最强。研究结果为农村低C/N污水的高效处理提供了理论依据和数据支撑。 展开更多
关键词 农村低c/n污水 倒置A^(2)/O MBR 胞外聚合物 关键酶
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Optimal Bidding and Operation of a Power Plant with Solvent-BasedCarbon Capture under a CO2 Allowance Market: A Solution with aReinforcement Learning-Based Sarsa Temporal-Difference Algorithm
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作者 Ziang Li Zhengtao Ding Meihong Wang 《Engineering》 SCIE EI 2017年第2期257-265,共9页
In this paper, a reinforcement learning (RL)-based Sarsa temporal-difference (TD) algorithm is applied tosearch for a unified bidding and operation strategy for a coal-fired power plant with monoethanolamine(MEA... In this paper, a reinforcement learning (RL)-based Sarsa temporal-difference (TD) algorithm is applied tosearch for a unified bidding and operation strategy for a coal-fired power plant with monoethanolamine(MEA)-based post-combustion carbon capture under different carbon dioxide (CO2) allowance market con-ditions. The objective of the decision maker for the power plant is to maximize the discounted cumulativeprofit during the power plant lifetime. Two constraints are considered for the objective formulation. Firstly,the tradeoff between the energy-intensive carbon capture and the electricity generation should be made un-der presumed fixed fuel consumption. Secondly, the CO2 allowances purchased from the CO2 allowance mar-ket should be approximately equal to the quantity of COs emission from power generation. Three case stud-ies are demonstrated thereafter. In the first case, we show the convergence of the Sarsa TD algorithm andfind a deterministic optimal bidding and operation strategy. In the second case, compared with the inde-pendently designed operation and bidding strategies discussed in most of the relevant literature, the SarsaTD-based unified bidding and operation strategy with time-varying flexible market-oriented CO2 capturelevels is demonstrated to help the power plant decision maker gain a higher discounted cumulative profit.In the third case, a competitor operating another power plant identical to the preceding plant is consideredunder the same CO2 allowance market. The competitor also has carbon capture facilities but applies a differ-ent strategy to earn profits. The discounted cumulative profits of the two power plants are then compared,thus exhibiting the competitiveness of the power plant that is using the unified bidding and operation strat-egy explored by the Sarsa TD algorithm. 展开更多
关键词 Power plants Post-combustion carbon capture chemical absorption c02 ALLOWAncE MARKET optimal decision-making Reinforcement learning
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N掺杂TiO_(2)-Fe_(2)O_(3)/C光催化剂的制备及其光催化降解性研究 被引量:2
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作者 李洁 张佳 +1 位作者 陈连喜 吕博 《化工新型材料》 北大核心 2025年第2期210-214,共5页
为寻找一种简便且具有良好孔结构的光催化剂合成路径,提升并拓宽其光催化应用范围,通过将N掺杂的双金属Ti-Fe MOFs在500℃的空气气氛中直接热解制备N掺杂TiO_(2)-Fe_(2)O_(3)/C纳米结构。获得的产物显示出独特的树枝状结构,且具有较大... 为寻找一种简便且具有良好孔结构的光催化剂合成路径,提升并拓宽其光催化应用范围,通过将N掺杂的双金属Ti-Fe MOFs在500℃的空气气氛中直接热解制备N掺杂TiO_(2)-Fe_(2)O_(3)/C纳米结构。获得的产物显示出独特的树枝状结构,且具有较大比表面积和良好的介孔结构。同时,红外光谱(FT-IR)和X射线光电子能谱(XPS)结果证实,在空气条件下煅烧后,衍生物仍保留了N和C成分。此外,将制备的N掺杂树枝状双金属结构多孔材料作为光催化剂用于降解亚甲基蓝(MB)染料。结果表明:N掺杂TiO_(2)-Fe_(2)O_(3)/C比N掺杂非Fe参与的TiO_(2)/C和非N非Fe掺杂TiO_(2)/C具有更好的光催化性能,且N掺杂TiO_(2)-Fe_(2)O_(3)/C对MB染料的有效降解率达到81%。 展开更多
关键词 Ti基-MOFs Fe基-MOFs TiO_(2)-Fe_(2)O_(3)/c n掺杂 光催化
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Fuzzy Logic Strategy for Solving an Optimal Control Problem of Therapeutic Hepatitis C Virus Dynamics
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作者 Jean Marie Ntaganda Mahamat Saleh Daoussa Haggar Benjamin Mampassi 《Open Journal of Applied Sciences》 2015年第9期527-541,共15页
This paper aims at the development of an approach integrating the fuzzy logic strategy for a therapeutic hepatitis C virus dynamics optimal control problem. To test the efficiency of this strategy, the authors propose... This paper aims at the development of an approach integrating the fuzzy logic strategy for a therapeutic hepatitis C virus dynamics optimal control problem. To test the efficiency of this strategy, the authors propose a numerical comparison with the direct method by taking the values of determinant parameters of this disease for people administrating the drugs. The results are in good agreement with experimental data. 展开更多
关键词 Fuzzy Logic optimal control MEMBERSHIP Function MEMBERSHIP Degree HEPATITIS c VIRUS Uninfected HEPATOcYTES InFEcTED HEPATOcYTES numerical Simulation
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芪苈强心胶囊治疗慢性心力衰竭的效果及对cTNI、Hcy、NT-proBNP、hs-CRP水平的影响 被引量:1
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作者 董红霞 高小花 +2 位作者 李小月 刘保东 刘广明 《中华中医药学刊》 北大核心 2025年第12期149-152,共4页
目的探讨芪苈强心胶囊治疗慢性心力衰竭的效果及对患者肌钙蛋白(cardiac troponin I,cTNI)、同型半胱氨酸(homocysteine,Hcy)、N末端B性利尿钠肽原(N-terminal pro-B-type natriuretic peptide,NT-proBNP)、超敏C反应蛋白(hypersensitiv... 目的探讨芪苈强心胶囊治疗慢性心力衰竭的效果及对患者肌钙蛋白(cardiac troponin I,cTNI)、同型半胱氨酸(homocysteine,Hcy)、N末端B性利尿钠肽原(N-terminal pro-B-type natriuretic peptide,NT-proBNP)、超敏C反应蛋白(hypersensitive C-reactive protein,hs-CRP)水平的影响。方法选取92例慢性心力衰竭患者,分为对照组与综合组各46例,常规综合治疗,综合组加用芪苈强心胶囊口服治疗3个月,观察疗效、中医证候积分、心功能及血清cTNI、Hcy、NT-proBNP、hs-CRP水平变化。结果两组治疗前中医证候主证及次证积分比较无统计学意义(P>0.05),治疗后积分下降(P<0.05),同时综合组低于对照组(P<0.05)。两组治疗前每搏输出量(stroke volume,SV)、左室舒张末期内径(left ventricular end diastolic diameter,LVEDD)、左室射血分数(left ventricular ejection fraction,LVEF)、6 min步行试验距离(6-minute walk test,6MWT)比较差异无统计学意义(P>0.05),治疗后SV、LVEF及6MWT升高(P<0.05),同时综合组高于对照组(P<0.05),治疗后LVEDD下降(P<0.05),同时综合组低于对照组(P<0.05)。两组治疗前血清cTNI、Hcy、NT-proBNP、hs-CRP水平比较差异无统计学意义(P>0.05),治疗后下降(P<0.05),同时综合组低于对照组(P<0.05)。综合组疗效整体优于对照组(P<0.05)。结论芪苈强心胶囊治疗慢性心力衰竭有助于降低患者血清cTNI、Hcy、NT-proBNP、hs-CRP水平,改善患者症状及心功能,进而提高治疗效果。 展开更多
关键词 芪苈强心胶囊 慢性心力衰竭 肌钙蛋白 同型半胱氨酸 n末端B性利尿钠肽原 超敏c反应蛋白 疗效
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YOLOv8n-CSG:轻量化钢材表面缺陷检测算法
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作者 赵佰亭 张敏 贾晓芬 《电子测量与仪器学报》 北大核心 2025年第8期115-125,共11页
为解决钢材表面缺陷检测中因缺陷类型繁多、尺寸差异显著造成检测精度低,以及现有模型复杂度高等问题,提出了一种改进YOLOv8n的轻量化检测算法YOLOv8n-CSG。首先,引入上下文引导模块(context guided block,CG block)设计C2f_CG模块增强... 为解决钢材表面缺陷检测中因缺陷类型繁多、尺寸差异显著造成检测精度低,以及现有模型复杂度高等问题,提出了一种改进YOLOv8n的轻量化检测算法YOLOv8n-CSG。首先,引入上下文引导模块(context guided block,CG block)设计C2f_CG模块增强对周围特征的捕捉能力,增强信息关联性;其次,加入星型网络模块(Star Block)设计出C2f_Star模块,将输入数据映射到高维的非线性特征空间,生成丰富的特征表示,使得模型在处理细微缺陷时更加有效;最后,设计了集成分组混洗卷积(grouped and shuffled convolution,GSConv)和高效多尺度注意力机制(efficient multi-Scale attention,EMA)的轻量化检测头GSE_Detect,保持了原检测头的高效的同时降低复杂度。在NEU-DET数据集上进行多组实验,结果表明,改进后的YOLOv8n-CSG网络模型平均精度均值(mAP)mAP@0.5达到了76.8%,相较于YOLOv8n,mAP@0.5提升了6.9%、精度提升了11.3%、计算量降低了37%、参数量降低了35.2%,展现出对钢材表面缺陷更佳的检测能力,且平衡了模型的性能和复杂度。 展开更多
关键词 缺陷检测 轻量化YOLOv8n c2f_cG c2f_Star GSE_Detect
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C/N原子比对Ti(C,N)基金属陶瓷组织结构和电化学腐蚀行为的影响
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作者 曹群 崔焱茗 +5 位作者 张立 曾瑞霖 龙坚战 尹超 成祥 包宇衡 《硬质合金》 2025年第4期17-24,共8页
以Ti(C_(0.4),N_(0.6))、Ti(C_(0.5),N_(0.5))和Ti(C_(0.7),N_(0.3))三种C/N原子比的Ti(C,N)粉末为原料,制备Ti(C,N)-25%WC-10%TaC-2%Mo_(2)C-7%Ni-7%Co金属陶瓷。采用扫描电镜、Tafel曲线和Nyquist图谱研究三种Ti(C,N)基金属陶瓷在pH=1... 以Ti(C_(0.4),N_(0.6))、Ti(C_(0.5),N_(0.5))和Ti(C_(0.7),N_(0.3))三种C/N原子比的Ti(C,N)粉末为原料,制备Ti(C,N)-25%WC-10%TaC-2%Mo_(2)C-7%Ni-7%Co金属陶瓷。采用扫描电镜、Tafel曲线和Nyquist图谱研究三种Ti(C,N)基金属陶瓷在pH=1的H_(2)SO_(4)溶液、pH=7的Na_(2)SO_(4)溶液以及pH=13的NaOH溶液中的电化学腐蚀行为。结果表明:随C/N原子比增加,硬质相芯部明显粗化,环形相厚度增加,白芯相数量增加,呈现出弱芯环结构。在电化学腐蚀过程中,Ti(C,N)基金属陶瓷在中性和碱性溶液中的耐腐蚀性能强于其在酸性溶液中的耐腐蚀性能。Ti(C,N)基金属陶瓷的腐蚀机理是:在酸性溶液中,黏结相优先发生腐蚀,Ni-Co基黏结相产生活性溶解,硬质相裸露在合金表面,直接与腐蚀溶液接触,导致硬质相被腐蚀。在中性和碱性溶液中,黏结相的腐蚀产物不易溶解,附在金属陶瓷表面,保护其不被腐蚀。 展开更多
关键词 TI(c n)基金属陶瓷 c/n原子比 微观组织结构 电化学腐蚀
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NT-proBNP、SAA、CRP与川崎病患儿病情严重程度及心血管病变易感性相关性的多项分类Logistic模型分析
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作者 陈征 李启亮 +3 位作者 金芳 张清秀 李爱华 梁雅慧 《现代生物医学进展》 2025年第1期65-71,共7页
目的:采用多项分类Logistic模型分析N末端B型利钠肽(NT-proBNP)、淀粉样蛋白A(SAA)、C反应蛋白(CRP)与川崎病患儿病情严重程度及心血管病变易感性的相关性。方法:选取2020.02~2022.08在我院治疗的川崎病患儿,共纳入例数为120例,将其作... 目的:采用多项分类Logistic模型分析N末端B型利钠肽(NT-proBNP)、淀粉样蛋白A(SAA)、C反应蛋白(CRP)与川崎病患儿病情严重程度及心血管病变易感性的相关性。方法:选取2020.02~2022.08在我院治疗的川崎病患儿,共纳入例数为120例,将其作为研究组。另选取在同一时间段内我院接收的健康体检儿童作为对照组,对照组例数为60例。根据患儿是否发生心血管病变分为心血管病变组和无心血管病变组,分别有64例、56例。根据患儿超声心电图检查结果,判断患儿疾病的严重程度,将患儿分为冠状动脉损害组和无冠状动脉损害组,分别有38例、82例。采用散射免疫比浊法测定患儿血清中SAA、CRP水平,采用全自动化学发光免疫分析仪测定患儿血清中NT-proBNP水平。结果:研究组患儿血清NT-proBNP、SAA、CRP水平均显著高于对照组(P<0.05)。冠状动脉损害组患儿治疗前发热时间显著长于无冠状动脉损害组(P<0.05);冠状动脉损害组患儿血清NT-proBNP、SAA、CRP水平均显著高于无冠状动脉损害组(P<0.05)。心血管病变组患儿血清NT-proBNP、SAA、CRP水平均显著高于无心血管病变组(P<0.05)。患儿年龄与川崎病严重程度呈明显的负相关(P<0.05),治疗前发热时间、血清NT-proBNP、SAA、CRP水平均与川崎病严重程度及心血管病变易感性呈明显的正相关(P<0.05)。Logistic结果显示,川崎病患儿病情加重及心血管病变易感性的危险因素均包括血清NT-proBNP、SAA、CRP,而川崎病患儿病情加重的保护因素为年龄(P<0.05)。结论:NT-proBNP、SAA、CRP均是川崎病患儿病情加重及心血管病变易感性的危险因素。 展开更多
关键词 n末端B型利钠肽 淀粉样蛋白A c反应蛋白 川崎病
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C≡N缺陷C3N5催化剂的制备及其光催化活化过硫酸盐降解亚甲基蓝性能
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作者 王淑敏 《毛纺科技》 北大核心 2025年第4期24-32,共9页
采用硫脲和3-氨基-1,2,4-三唑混合原位热聚合制备C≡N缺陷C_(3)N_(5)(C_(3)N_(5)—C≡N)光催化剂,通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)、扫描电镜(SEM)、X射线光电子能谱(XPS)、电子顺磁共振波谱(EPR)、紫外可见漫反射光谱(UV-vis... 采用硫脲和3-氨基-1,2,4-三唑混合原位热聚合制备C≡N缺陷C_(3)N_(5)(C_(3)N_(5)—C≡N)光催化剂,通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)、扫描电镜(SEM)、X射线光电子能谱(XPS)、电子顺磁共振波谱(EPR)、紫外可见漫反射光谱(UV-vis DRS)和稳态荧光光谱(PL)等表征手段对C_(3)N_(5)—C≡N光催化剂的物相晶型、特征基团、微观形貌、元素组成、缺陷构建、光谱吸收响应和光电子-空穴重组等进行了详细分析。结果表明:波数2176 cm^(-1)位置吸收峰和286.5 eV位置拟合峰的出现证明了C≡N缺陷的成功构建,Lorentz信号强度的增强说明缺陷的构建促进了未配对电子的生成,发射峰的降低说明了光电子-空穴的重组得到了有效抑制,吸收边界的红移说明了光谱响应范围得到拓宽,有利于光催化性能的提升。太阳光照射下,C_(3)N_(5)—C≡N光催化剂协同过硫酸盐(PMS)表现出优异的光催化活性,对亚甲基蓝(MB)染料溶液的降解率达到了99.10%,循环使用5次后MB染料溶液的降解率为97.80%,表现出良好的化学稳定性。活性基团捕获说明超氧自由基(·O_(2)^(-))、空穴(h^(+))、单线态氧(^(1)O_(2))、羟基自由基(·OH)和硫酸根自由基(·SO_(4)^(-))均参与了反应,·O_(2)^(-)和^(1)O_(2)起主要作用。 展开更多
关键词 cn缺陷 富氮氮化碳 光催化 过硫酸盐 亚甲基蓝
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