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Negative effects of artiffcial nest boxes on birds:A review
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作者 Luchang Zhang Xingjian Ma +4 位作者 Zhiyu Chen Chunying Wang Zicheng Liu Xiang Li Xiaoying Xing 《Avian Research》 SCIE CSCD 2023年第2期257-266,共10页
Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artific... Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artificial nest boxes can adversely affect breeding fitness but no great focus has been placed on this issue by researchers.Therefore,we retrieved 321 research papers regarding artificial nest boxes published from 2003 to 2022 and used the'Biblioshiny'program to extract and integrate keywords;we then summarized the adverse effects of artificial nest boxes on avian breeding success.The studies highlighted many drawbacks and misuses in the designing and placement of nest boxes;furthermore,bird attraction was decreased by their inappropriate selection,thus reducing breeding success.Regarding nest box production,there were shortcomings in the construction material,color,smell,and structural design of the boxes used.Nest boxes were also placed at inappropriate densities,locations,orientations,heights,and managed incorrectly.Finally,we propose suggestions for more efficient and safer artificial nest boxes for future use in avian ecology research and bird conservation. 展开更多
关键词 Artificial nest box Avian breeding Management Negative effect Nest box hanging Nest box location Nest box structure
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基于Edge Boxes的大型车辆车标检测与识别 被引量:3
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作者 李熙莹 吕硕 +2 位作者 江倩殷 袁敏贤 余志 《计算机工程与应用》 CSCD 北大核心 2018年第12期152-159,共8页
传统车标检测与识别算法难以检测大型车辆车标,且速度较慢。提出了一种基于Edge Boxes的大型车辆车标检测与识别方法。Edge Boxes算法是一种成熟的图像分割算法,能够快速且有效地检测物体位置,满足大型车辆车标检测与识别问题的准确性... 传统车标检测与识别算法难以检测大型车辆车标,且速度较慢。提出了一种基于Edge Boxes的大型车辆车标检测与识别方法。Edge Boxes算法是一种成熟的图像分割算法,能够快速且有效地检测物体位置,满足大型车辆车标检测与识别问题的准确性及实时性的需求。该方法首先根据车标在车辆中的空间位置关系初选车标候选区,然后利用Edge Boxes算法进行目标提取,进而将提取得到的目标送入利用线性约束编码构建的车标检测分类器和车标识别分类器进行训练与识别,得到车标检测与识别结果。对不同卡口的不同天气和光照条件下采集的4 480张图像(含50类大型车辆)进行实验,实验结果表明,在检测与识别性能以及时间消耗方面均优于传统方法,具有良好的实用前景。 展开更多
关键词 大型车辆 车标检测与识别 Edge boxes 线性约束编码 车标定位分类器 车标识别分类器
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一种改进的基于再励学习算法的模糊神经BOXES控制系统 被引量:2
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作者 马勇 许晓鸣 张卫东 《模糊系统与数学》 CSCD 2000年第1期78-83,共6页
本文给出了一种改进的基于再励算法的神经网络 BOXES控制系统 ,引入超维椭球体模糊划分状态空间的概念 ,并且通过神经网络的再励学习实现了对状态空间的自动划分。最后 ,应用到倒立摆控制中的仿真结果展示了控制系统的有效性。
关键词 模糊boxes控制系统 再励学习算法 模糊控制
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A Review of Existing 4-Bit Crypto S-Box Cryptanalysis Techniques and Two New Techniques with 4-Bit Boolean Functions for Cryptanalysis of 4-Bit Crypto S-Boxes
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作者 Sankhanil Dey Ranjan Ghosh 《Advances in Pure Mathematics》 2018年第3期272-306,共35页
4-bit linear relations play an important role in cryptanalysis of 4-bit crypto S-boxes. 4-bit finite differences have also been a major part of cryptanalysis of 4-bit S-boxes. Existence of all 4-bit linear relations h... 4-bit linear relations play an important role in cryptanalysis of 4-bit crypto S-boxes. 4-bit finite differences have also been a major part of cryptanalysis of 4-bit S-boxes. Existence of all 4-bit linear relations have been counted for all of 16 input and 16 output 4-bit bit patterns of 4-bit Crypto S-boxes said as S-boxes has been reported in Linear Cryptanalysis of 4-bit S-boxes. Count of existing finite differences from each element of output S-boxes to distant output S-boxes have been noted in Differential Cryptanalysis of S-boxes. In this paper a brief review of these two cryptanalytic methods for 4-bit S-boxes has been introduced in a very lucid and conceptual manner. Two new analysis techniques, one to search for the existing linear approximations among the input vectors (IPVs) and output Boolean functions (BFs) of a particular S-box has also been introduced in this paper. The search is limited to find the existing linear relations or approximations in the contrary to count the number of existent linear relations among all 16, 4-bit input and output bit patterns within all possible linear approximations. Another is to find number of balanced BFs in difference output S-boxes. Better the number of Balanced BFs, Better the security. 展开更多
关键词 Linear CRYPTANALYSIS Differential CRYPTANALYSIS Substitution boxes S-boxes CRYPTOGRAPHY CRYPTANALYSIS
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基于Edge Boxes和深度学习的车辆检测 被引量:2
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作者 刘亚萍 姚剑 《黑龙江科技信息》 2016年第1期102-102,共1页
传统的基于机器学习的车辆检测无法自适应地提取图像的典型特征,本文提出了基于深度学习的检测方法,并用Edge Boxes算法提取车辆的预选区域以取代传统的多尺度滑动窗口搜索策略。在高分辨率卫星影像上的实验证明了本算法的有效性。
关键词 深度学习 EDGE boxes 车辆检测
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基于Edge Boxes和深度学习的非限制条件下人脸检测 被引量:2
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作者 刘英剑 张起贵 《现代电子技术》 北大核心 2018年第13期29-33,共5页
针对光线、旋转、遮挡、平移等因素对人脸检测结果产生的干扰,提出一种基于Edge Boxes和深度学习相结合的人脸检测算法。首先采用Edge Boxes算法提取出可能存在人脸的边界框,提取边界框中的图像并调整至合适的大小,作为卷积神经网络的输... 针对光线、旋转、遮挡、平移等因素对人脸检测结果产生的干扰,提出一种基于Edge Boxes和深度学习相结合的人脸检测算法。首先采用Edge Boxes算法提取出可能存在人脸的边界框,提取边界框中的图像并调整至合适的大小,作为卷积神经网络的输入,然后利用卷积神经网络对提取出的图像进行特征提取和分类,最后利用非极大抑制算法排除多余人脸检测框,得到人脸的准确位置。该算法应用于LFW和Yale B人脸数据库的检测率分别达到98.7%和98.5%,识别单张人脸的时间均小于0.5 s。实验结果表明,该算法在检测率和检测速率方面较传统算法都有了很大的提高,对于遮挡、光照、旋转等干扰具有更强的鲁棒性。 展开更多
关键词 人脸检测 特征提取 深度学习 EDGE boxes 卷积神经网络 非极大抑制算法
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洛阳地区回族人群RHD基因Rhesus boxes研究 被引量:1
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作者 杨波 吕运来 兰炯采 《中国输血杂志》 CAS CSCD 北大核心 2014年第9期904-906,共3页
目的探讨洛阳地区回族人群RHD基因Rhesus boxes特征,并判定RHD杂合性。方法收集洛阳地区不同RhD表型的回族献血者血液492例,应用PCR-SSP技术检测RHD基因Rhesus boxes。结果在425例D阳性标本中,同时检出Up box和Down box标本有352例(82.8... 目的探讨洛阳地区回族人群RHD基因Rhesus boxes特征,并判定RHD杂合性。方法收集洛阳地区不同RhD表型的回族献血者血液492例,应用PCR-SSP技术检测RHD基因Rhesus boxes。结果在425例D阳性标本中,同时检出Up box和Down box标本有352例(82.82%),为RHD+/RHD+纯合子;同时检出Hybrid、Up及Down box标本有73例(17.18%),为RHD+/RHD-杂合子。在弱D和Del标本中,同时检出Up box和Down box标本数分别为4例(44.44%)和4例(25.00%),同时检测到Hybrid、Up及Down box标本数分别为5例(55.56%)和12例(75.00%),未能单独检测出杂交Rhesus box。在42例RhD阴性标本中,同时检测到Hybrid、Up及Down box标本有3例(7.14%),仅检出Hybrid box标本有39例(92.86%),未能同时检测出Up box和Down box。结论洛阳地区回族人群中RHD基因Rhesus boxes具有独特的分布特征,应用Rhesus boxes来确定RHD基因杂合性在临床输血和产前预防RhD新生儿溶血病有重要意义。 展开更多
关键词 血型 RHD基因 RHESUS BOX 杂合性
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Influence of forest road on breeding of tits in artificial nest boxes 被引量:3
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作者 Young-Su Park Woo-Shin Lee Shin-Jae Rhim 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期301-302,共2页
A study was conducted to determine the influence of forest road on breeding of tits in artificial nest boxes in deciduous, coniferous and mixed forests in the Gwanak Arboretum (37° 25′ 05" N, 126° 56′ 85... A study was conducted to determine the influence of forest road on breeding of tits in artificial nest boxes in deciduous, coniferous and mixed forests in the Gwanak Arboretum (37° 25′ 05" N, 126° 56′ 85" E) of Seoul National University, Anyang, Korea from November 2002 to June 2003. Three tits species, varied tit (Parus varius), marsh tit (P. palustris) and great tit (P. major), breeding in artificial t nest boxes were investigated on number of breeding pairs, cultch size, and egg measurement. Resuls showed that the breeding pairs of varied tit was more in 75-150 m area than in 0-75m area from forest road for all the three study sites, and the clutch size and egg measurements (weight, Major axis and Minor axis) of varied tit was also higher in the area of 75-150 m than in the area of 0-75 m, while no differences in number of breeding pairs and clutch size were found for marsh tit and great tit between the two areas. Egg measurement of great tit was also higher in forest interior area than in forest edge area. It is concluded that varied tit were most significantly influenced by forest road, followed by great tit, whereas marsh tit were not influenced by forest road. Artificial nest box is roved to be good for cavity nester in disturbed areas by human activities. Supply of artificial nest can help population protection and management of bird species. 展开更多
关键词 Artificial nest boxes BREEDING Forest road TITS
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Nano storage-boxes constructed by the vertical growth of MoS_(2 )on graphene for high-performance Li-S batteries 被引量:2
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作者 Bowen Cui Xiaomin Cai +2 位作者 Wenqiang Wang Petr Saha Gengchao Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期91-99,I0004,共10页
In order to accelerate the reaction kinetics of lithium-sulfur batteries, the introduction of electro catalysis and proper structural control of the sulfur cathode is urgently needed. MoS_(2) nano sheets was selective... In order to accelerate the reaction kinetics of lithium-sulfur batteries, the introduction of electro catalysis and proper structural control of the sulfur cathode is urgently needed. MoS_(2) nano sheets was selectively grown vertically (V-MoS_(2)) on the microwave-reduced graphene (rGO) sheets through chemical coupling to construct a self-supporting sulfur cathode with a nano storage-box structure (V-MoS_(2) as the wall and rGO as the bottom). RGO, which has a high conductivity of 37 S cm^(−1), greatly accelerates the transfer of electrons from the active sites on the edge of the layer to the solution. The introduction of carbon tubes can connect the abundant pores in the foam and act as a long-range conductive path. The 2D-orthogonal-2D structure maximally exposes the edge active sites of MoS_(2), and together with graphene form a nano reactor of sulfur, intermediate lithium polysulfides and discharge product Li_(2)S(2). The effective combination of the microstructure confinement of the nano storage-boxes and the efficient synchronous catalytic mechanism of V-MoS_(2) greatly improves the electrochemical performance of the lithium-sulfur batteries. As a result, the assembled lithium-sulfur battery displays a high initial discharge capacity of 1379 mAh g^(−1), good cycle stability (86% capacity retention after 500 cycles at 0.1C) and superior rate performance. 展开更多
关键词 Edge-rich MoS_(2) Nano boxes Catalytic conversion Lithium-sulfur batteries
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Multi-view recognition of fruit packing boxes based on features clustering angle
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作者 李鑫宁 Wu Hu Yang Xianhai 《High Technology Letters》 EI CAS 2021年第2期200-209,共10页
In order to realize the intelligent mechanization of the last process of the fruit industry chains,the identification of fruit packing boxes is researched.A multi-view database is established to describe the omnidirec... In order to realize the intelligent mechanization of the last process of the fruit industry chains,the identification of fruit packing boxes is researched.A multi-view database is established to describe the omnidirectional attitudes of the fruit packing boxes.In order to reduce the data redundancy caused by multi-view acquisition,a new binary multi-view kernel principal component analysis network(BMKPCANet) is built,and a multi-view recognition method of fruit packing boxes is proposed based on the BMKPCANet and support vector machine(SVM).The experimental results show that the recognition accuracy of proposed BMKPCANet is 12.82% higher than PCANet and3.51% higher than KPCANet on average.The time consumption of proposed BMKPCANet is 7.74%lower than PCANet and 29.01% lower than KPCANet on average.This work has laid a theoretical foundation for multi-view recognition of 3 D objects and has a good practical application value. 展开更多
关键词 boxes recognition kernel principal component analysis(KPCA) binary hashing and clustering multi-view clustering(MVC)
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Strive for the Modern Town with the Specialized Production of Boxes and Bags——Sidelights on Nantai Town Economy
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《China's Foreign Trade》 2002年第3期63-63,共1页
关键词 Sidelights on Nantai Town Economy Strive for the Modern Town with the Specialized Production of boxes and Bags
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Strive for the Modern Town with the Specialized Production of Boxes and Bags——Sidelights on Nantai Town Economy
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《China's Foreign Trade》 2002年第5期61-61,共1页
Nantai town is located at the south of Liaoning Province, North is Anshan, Haichengis on the south, Shenda expressway, Hada highway and railway crisscross the town fromnorth to south. Nantai town covers an areas of 95... Nantai town is located at the south of Liaoning Province, North is Anshan, Haichengis on the south, Shenda expressway, Hada highway and railway crisscross the town fromnorth to south. Nantai town covers an areas of 95 square Kgs with 23 administrativevillages, 4 sub-district offices, 1 economic development zone and there are 15 thousandfamilies and 54 thousand populations. Nantai town is a trial place for overall structuralreform in Liaoning Province and a center on larger-scale production, processing anddistributing of boxes and bags nationwide. 展开更多
关键词 Sidelights on Nantai Town Economy Strive for the Modern Town with the Specialized Production of boxes and Bags
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The use of artificial nest boxes by Siberian flying squirrels (Pteromys volans) in South Korea
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作者 Jong-U Kim Woo-shin Lee Eun-Jae Lee 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期1131-1137,共7页
In this study, we examined the use of artificial nest boxes by Siberian flying squirrels (Pteromys volans) in three coniferous and mixed forests in Gangwon Province, South Korea. Six hundred and twelve boxes with diff... In this study, we examined the use of artificial nest boxes by Siberian flying squirrels (Pteromys volans) in three coniferous and mixed forests in Gangwon Province, South Korea. Six hundred and twelve boxes with different sized entry holes (ranging from 3 to 7 cm in diameter) were placed in the forests between 2004 and 2009. Pteromys volans used nine boxes in the coniferous forests and two boxes in the mixed forests. The squirrels only used boxes with entrance holes measuring 3.5, 4, and 5 cm in diameter, showing a strong and moderate preference for boxes with 5 and 4-cm holes, respectively, and a strong avoidance for boxes with 3- and 7-cm holes. Therefore, we suggest placing artificial nest boxes with entrance holes 5 cm in diameter to encourage breeding activity. Most nests made in the artificial boxes were composed of fibrous materials from woody vines. We recommend placing artificial nest boxes with holes of 5-cm diameter in coniferous forests, which support dense populations of P. volans, to survey whether this approach would positively affect the breeding habits and population maintenance of this species. 展开更多
关键词 Artificial NEST box CONIFEROUS forests NEST materials Siberian flying SQUIRREL WOODY VINES
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Scanning and Selection Methods Using Solution Boxes of Inequality
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作者 Ferenc Kálovics 《Applied Mathematics》 2010年第6期520-528,共9页
Numerical methods often reduce solving a complicated problem to a set of elementary problems. In some previous papers, the author reduced the finding of solution boxes of a system of inequalities, the computation of i... Numerical methods often reduce solving a complicated problem to a set of elementary problems. In some previous papers, the author reduced the finding of solution boxes of a system of inequalities, the computation of integral value with error bound, the approximation of global maxima to computing solution boxes of one inequality. This paper contains new and improved methods for application of solution boxes of an inequality, furthermore the computational aspects are discussed in detail. 展开更多
关键词 INEQUALITY SOLUTION BOX SCANNING of SET
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Construction and Optimization of TRNG Based Substitution Boxes for Block Encryption Algorithms
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作者 Muhammad Fahad Khan Khalid Saleem +4 位作者 Mohammed Alotaibi Mohammad Mazyad Hazzazi Eid Rehman Aaqif Afzaal Abbasi Muhammad Asif Gondal 《Computers, Materials & Continua》 SCIE EI 2022年第11期2679-2696,共18页
Internet of Things is an ecosystem of interconnected devices that are accessible through the internet.The recent research focuses on adding more smartness and intelligence to these edge devices.This makes them suscept... Internet of Things is an ecosystem of interconnected devices that are accessible through the internet.The recent research focuses on adding more smartness and intelligence to these edge devices.This makes them susceptible to various kinds of security threats.These edge devices rely on cryptographic techniques to encrypt the pre-processed data collected from the sensors deployed in the field.In this regard,block cipher has been one of the most reliable options through which data security is accomplished.The strength of block encryption algorithms against different attacks is dependent on its nonlinear primitive which is called Substitution Boxes.For the design of S-boxes mainly algebraic and chaos-based techniques are used but researchers also found various weaknesses in these techniques.On the other side,literature endorse the true random numbers for information security due to the reason that,true random numbers are purely non-deterministic.In this paper firstly a natural dynamical phenomenon is utilized for the generation of true random numbers based S-boxes.Secondly,a systematic literature review was conducted to know which metaheuristic optimization technique is highly adopted in the current decade for the optimization of S-boxes.Based on the outcome of Systematic Literature Review(SLR),genetic algorithm is chosen for the optimization of s-boxes.The results of our method validate that the proposed dynamic S-boxes are effective for the block ciphers.Moreover,our results showed that the proposed substitution boxes achieve better cryptographic strength as compared with state-of-the-art techniques. 展开更多
关键词 IoT security sensors data encryption substitution box generation True Random Number Generators(TRNG) heuristic optimization genetic algorithm
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Design of Dismantling and Recycling Equipment for Junction Boxes of Waste Crystal Silicon Photovoltaic Modules
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作者 Zhansheng ZHANG Yunfeng MA +3 位作者 Lu ZHENG Litong NIU Yi ZHANG Fei ZHENG 《Meteorological and Environmental Research》 CAS 2022年第5期68-72,共5页
The dismantling and recycling of junction boxes,which is an important part of the photovoltaic module recycling process,was tested and designed scientifically.The equipment framework was built by three-dimensional sim... The dismantling and recycling of junction boxes,which is an important part of the photovoltaic module recycling process,was tested and designed scientifically.The equipment framework was built by three-dimensional simulation,and then the design of dismantling and recycling equipment for junction boxes of waste crystal silicon photovoltaic modules was completed through the experimental test and data analysis.The experimental results show that the initial idea of the dismantling scheme is correct,and the structure is feasible.However,some problems were not considered.This study provides reliable data support for the subsequent equipment development and ensures the smooth development of the subsequent design work. 展开更多
关键词 Waste photovoltaic modules RECYCLING Junction box dismantling Three-dimensional simulation Equipment development
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A New Tool: Solution Boxes of Inequality
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作者 Ferenc Kálovics 《Journal of Software Engineering and Applications》 2010年第8期737-745,共9页
Many numerical methods reduce the solving of a complicated problem to a set of elementary problems. In this way, the author reduced the finding of solution boxes of a system of inequalities, the computation of integra... Many numerical methods reduce the solving of a complicated problem to a set of elementary problems. In this way, the author reduced the finding of solution boxes of a system of inequalities, the computation of integral values with error bounds, the approximation of global maxima to computing solution boxes of one inequality. These previous papers presented the mathematical aspects of the problems first of all. In this paper the computational handling of solution boxes of an inequality (as a new tool of computer methods) is discussed in detail. 展开更多
关键词 INEQUALITY SOLUTION BOX CODED FORM of Expression
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An Uncertain Optimal Energy Flow Model for CCHP Campus Microgrid Using Parameterized Probability Boxes
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作者 Shunjiang Lin Xuan Sheng +2 位作者 Yuquan Xie Yanghua Liu Mingbo Liu 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第5期1618-1633,共16页
Due to the uncertain fluctuations of renewable energy and load power, the state variables such as bus voltages and pipeline mass flows in the combined cooling, heating, and power campus microgrid(CCHP-CMG) may exceed ... Due to the uncertain fluctuations of renewable energy and load power, the state variables such as bus voltages and pipeline mass flows in the combined cooling, heating, and power campus microgrid(CCHP-CMG) may exceed the secure operation limits. In this paper, an optimal energy flow(OEF) model for a CCHP-CMG using parameterized probability boxes(p-boxes) is proposed to describe the higher-order uncertainty of renewables and loads. In the model, chance constraints are used to describe the secure operation limits of the state variable p-boxes, and variance constraints are introduced to reduce their random fluctuation ranges. To solve this model, the chance and variance constraints are transformed into the constraints of interval cumulants(ICs) of state variables based on the p-efficient point theory and interval Cornish-Fisher expansion. With the relationship between the ICs of state variables and node power, and using the affine interval arithmetic method, the original optimization model is finally transformed into a deterministic nonlinear programming model. It can be solved by the CONOPT solver in GAMS software to obtain the optimal operation point of a CCHP-CMG that satisfies the secure operation requirements considering the higher-order uncertainty of renewables and loads. Case study on a CCHP-CMG demonstrates the correctness and effectiveness of the proposed OEF model. 展开更多
关键词 Combined cooling heating and power campus microgrid(CCHP-CMG) chance-constrained programming higher-order uncertainty optimal energy flow parameterized probability box
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煤化工合成气低温分离工艺优化与分析
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作者 杨佳原 盛伟 +2 位作者 郑海坤 朱鉴宇 李志永 《石油与天然气化工》 CAS CSCD 北大核心 2024年第1期54-60,共7页
目的以新疆哈密某公司煤化工工艺过程为研究对象,解决煤化工合成气低温分离液化系统高能耗问题。方法通过Aspen HYSYS软件模拟了单级混合制冷剂合成天然气分离液化流程,采用BOX算法,以系统最低能耗为目标函数,冷箱最小换热温差3℃为约... 目的以新疆哈密某公司煤化工工艺过程为研究对象,解决煤化工合成气低温分离液化系统高能耗问题。方法通过Aspen HYSYS软件模拟了单级混合制冷剂合成天然气分离液化流程,采用BOX算法,以系统最低能耗为目标函数,冷箱最小换热温差3℃为约束条件,优化了混合制冷剂组分配比及混合制冷剂循环一、二级压缩压力。结果在保证LNG和制甲醇原料气产量不变的前提下,优化后冷箱冷热复合曲线更接近且平滑,换热效果更优,系统总能耗降低了16.59%,火用效率由37.96%提升至43.04%,显著提高了能源利用率。结论BOX算法优化混合冷剂配比及压缩压力对降低合成气液化工艺能耗、提高系统火用效率有显著效果,对煤化工合成气低温分离液化工艺的研究具有借鉴意义。 展开更多
关键词 煤化工 低温分离 HYSYS模拟 BOX算法 火用效率
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银柴胡多糖超声辅助提取工艺优化及抗氧化活性分析
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作者 王红 彭励 +4 位作者 宋乐 冯璐 李振凯 李彦青 高跳 《食品工业科技》 CAS 北大核心 2024年第1期185-191,共7页
目的:为了提高银柴胡多糖得率,对银柴胡多糖提取工艺参数进行优化,并评价其体外抗氧化活性。方法:采用超声辅助提取银柴胡多糖,在单因素实验基础上结合响应面法(Box–Behnken Response Surface)对提取工艺参数进行优化,并采用Sevag法除... 目的:为了提高银柴胡多糖得率,对银柴胡多糖提取工艺参数进行优化,并评价其体外抗氧化活性。方法:采用超声辅助提取银柴胡多糖,在单因素实验基础上结合响应面法(Box–Behnken Response Surface)对提取工艺参数进行优化,并采用Sevag法除蛋白得银柴胡粗多糖,进一步对其抗氧化活性进行分析。结果:优化后银柴胡多糖最佳提取工艺参数为超声温度50℃、时间3.20 h、提取次数2次,在此条件下多糖得率最高,为28.24%±0.10%,多糖含量为59.13%;体外抗氧化测定结果显示,银柴胡粗多糖清除DPPH自由基、OH自由基、ABTS+自由基的IC_(50)分别是5.47、2.40和1.44 mg/mL,表明其具有一定的抗氧化能力。结论:本研究经优化得到的银柴胡多糖提取工艺切实可行,可为银柴胡资源的开发利用提供理论依据。 展开更多
关键词 银柴胡 多糖 提取 Box–Behnken响应面法 抗氧化活性
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