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传统SMB、Varicol和Partial-discard工艺分离纯化ECG和EGCG的比较研究 被引量:2
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作者 黄永东 江和源 +5 位作者 江用文 张建勇 王斌 白艳 文志浩 王伟伟 《茶叶科学》 CAS CSCD 北大核心 2011年第3期201-210,共10页
使用B型三带模拟移动床技术,以C18键合硅胶为固定相,乙醇与水(20︰80,V/V)为流动相,分别采取传统SMB工艺、Varicol工艺和Partial-discard工艺分离98%的茶多酚(TP98)。以得到高纯度和高回收率的ECG和EGCG为目标,分别优化柱配置、切换时... 使用B型三带模拟移动床技术,以C18键合硅胶为固定相,乙醇与水(20︰80,V/V)为流动相,分别采取传统SMB工艺、Varicol工艺和Partial-discard工艺分离98%的茶多酚(TP98)。以得到高纯度和高回收率的ECG和EGCG为目标,分别优化柱配置、切换时间、进样流速、冲洗流速。结果表明,采用Varicol工艺能得到纯度为91.33%的ECG,回收率为91.41%;采用Partial-discard工艺能得到纯度为90.12%的EGCG,回收率为97.83%。相对于传统模拟移动床,Varicol工艺具有提高产品纯度和回收率的优点,Partial-discard工艺具有提高收集液浓度和产品纯度的优点。 展开更多
关键词 模拟移动床 EGCG ECG Varicol工艺 partial-discard工艺
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坐标转换Partial-EIV总体最小二乘方法 被引量:4
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作者 王乐洋 郑玄威 +2 位作者 申兴林 许光煜 于冬冬 《测绘工程》 CSCD 2015年第12期12-16,共5页
在测量数据处理过程中,针对系数矩阵中同时存在随机元素和固定元素的情况,Xu等通过将随机元素分离使EIV模型推广到Partial-EIV模型,并给出基于Partial-EIV模型的总体最小二乘(TLS)算法。文中介绍该算法,并将其应用在平面及空间的坐标转... 在测量数据处理过程中,针对系数矩阵中同时存在随机元素和固定元素的情况,Xu等通过将随机元素分离使EIV模型推广到Partial-EIV模型,并给出基于Partial-EIV模型的总体最小二乘(TLS)算法。文中介绍该算法,并将其应用在平面及空间的坐标转换中,通过与最小二乘(LS)、总体最小二乘(TLS)及加权总体最小二乘(WTLS)方法的比较和分析,验证该算法有效性。 展开更多
关键词 总体最小二乘 partial-EIV模型 函数模型 系数矩阵 坐标转换
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基于Partial-EIV模型的TLS姿态估计方法 被引量:2
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作者 田源 隋立芬 +3 位作者 高成胜 王冰 文娜 田翌君 《测绘科学技术学报》 CSCD 北大核心 2017年第6期587-592,共6页
推导了基于乘性姿态角误差的观测方程,顾及其系数矩阵也含有误差的特点提出一种利用整体最小二乘原理估计姿态参数的新思路。该问题的系数矩阵中同时存在随机元素和固定元素且存在结构性特征,故引入Partial-EIV模型,设计了一种符合其系... 推导了基于乘性姿态角误差的观测方程,顾及其系数矩阵也含有误差的特点提出一种利用整体最小二乘原理估计姿态参数的新思路。该问题的系数矩阵中同时存在随机元素和固定元素且存在结构性特征,故引入Partial-EIV模型,设计了一种符合其系数矩阵结构特点的新模型。最后通过两组仿真实验将其与已有姿态估计方法进行对比,得出结论:基于Partial-EIV模型的整体最小二乘解法解算精度高于常规最小二乘法;其解算效果与基于乘性姿态角误差的最小二乘法基本一致。表明本文提出的方法正确有效。 展开更多
关键词 多天线测姿 姿态参数估计 乘性姿态误差 整体最小二乘 partial-EIV模型
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基于partial-EIV模型的WTLS算法在三维坐标变换中的应用 被引量:2
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作者 王东阁 邱卫宁 +1 位作者 王刘准 赵杰 《测绘地理信息》 2015年第5期8-12,共5页
通过考虑系数矩阵各个元素之间的关系,推导了基于partial_EIV模型附有相对权比的WTLS算法,并通过解算三维基准转换模型和求取ITRF框架转换参数验证其可行性。算例证明,基于partial_EIV模型的WTLS算法能够更快得到更合理的结果。
关键词 partial_EIV模型 WTLS算法 小角度基准转换
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Separation of Salbutamol by Nano-baskets of Calix[4]arene Bearing Sulfonyl-carboxamides in Partial-cone Conformation 被引量:3
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作者 MOKHTARI Bahram POURABDOLLAH Kobra 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第6期1112-1118,共7页
Salbutamol,which increases the muscle mass and decreases the adipose tissue,is misused as nutrient repartitioning agent in the livestock.The novelty of this work is the determination of salbutamol in the livestock mea... Salbutamol,which increases the muscle mass and decreases the adipose tissue,is misused as nutrient repartitioning agent in the livestock.The novelty of this work is the determination of salbutamol in the livestock meat via new bonded-phases bearing eight derivatives of p-tert-calix[4]arene in partial-cone conformation.The new synthesized bonded-phases were characterized and optimized.The bonding interactions of solute and stationary-phases were examined and the main interactions were reported.The salbutamol levels in six samples of livestock meat were analyzed and the results reveal that for the best bonded-phases,the limit of detection(LOD) and limit of quantitation(LOQ) were 0.02 and 0.06 μg/mL,respectively. 展开更多
关键词 NANO-BASKET Bonded-phase partial-cone conformation CALIX[4]ARENE SALBUTAMOL
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A new structure and its analytical model for the vertical interface electric field of a partial-SOI high voltage device 被引量:2
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作者 胡盛东 张波 +1 位作者 李肇基 罗小蓉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期496-502,共7页
A new partial-SOI (PSOI) high voltage device structure called a CI PSOI (charge island PSOI) is proposed for the first time in this paper. The device is characterized by a charge island layer on the interface of t... A new partial-SOI (PSOI) high voltage device structure called a CI PSOI (charge island PSOI) is proposed for the first time in this paper. The device is characterized by a charge island layer on the interface of the top silicon layer and the dielectric buried layer in which a series of equidistant high concentration n+-regions is inserted. Inversion holes resulting from the vertical electric field are located in the spacing between two neighbouring n+-regions on the interface by the force with ionized donors in the undepleted n+-regions, and therefore effectively enhance the electric field of the dielectric buried layer (Ei) and increase the breakdown voltage (BV), thereby alleviating the self-heating effect (SHE) by the silicon window under the source. An analytical model of the vertical interface electric field for the CI PSOI is presented and the analytical results are in good agreement with the 2D simulation results. The BV and El of the CI PSOI LDMOS increase to 631 V and 584 V/μm from 246 V and 85.8 V/μm for the conventional PSOI with a lower SHE, respectively. The effects of the structure parameters on the device characteristics are analysed for the proposed device in detail. 展开更多
关键词 interface charges breakdown voltage partial-SOI self-heating effect
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Study of LDPC Coded SFH System with Partial-Band Interference 被引量:3
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作者 Chao Gong Manxi Wang +1 位作者 Daoxing Guo Xiaofei Pan 《Communications and Network》 2013年第3期280-285,共6页
The application of Low Density Parity Check (LDPC) code in the anti-interference systems has drawn an increasing attention, due to its admiring performance which is very close to the theory limit. This paper focuses o... The application of Low Density Parity Check (LDPC) code in the anti-interference systems has drawn an increasing attention, due to its admiring performance which is very close to the theory limit. This paper focuses on a LDPC encoded slow frequency hopping (SFH) communication system with partial-band interference. Firstly, a modified soft- decision algorithm based on the utilization of interference information is proposed, and its performance is compared with some other soft-decision methods. Secondly, with numerical simulation, the influence of code rate, code length and the number of symbols per hops on the performance of the system with partial band noise interference is illustrated and examined in detail. Considering the great influence of hops per symbol on the performance, interleaver should be used and its influence on the performance is further examined by simulation. Finally, some constructive advises for the design of LDPC coded SFH system are given. Simulation results show that, with a reasonable design, the SFH system with LDPC code could achieve a desirable performance. 展开更多
关键词 LDPC SFH Soft-decision partial-band INTERFERENCE
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Partial-EIV数据探测法在三维坐标转换中的应用 被引量:1
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作者 王铮尧 倪标 《地理空间信息》 2019年第9期116-118,I0003,共4页
在三维坐标转换中,起始和目标坐标系下的点坐标均可能存在粗差,利用总体最小二乘法求解坐标转换参数时会对计算结果产生较大影响。为了降低粗差对计算结果的影响,利用基于Partial-EIV模型的数据探测法对原始数据进行粗差剔除,以保证结... 在三维坐标转换中,起始和目标坐标系下的点坐标均可能存在粗差,利用总体最小二乘法求解坐标转换参数时会对计算结果产生较大影响。为了降低粗差对计算结果的影响,利用基于Partial-EIV模型的数据探测法对原始数据进行粗差剔除,以保证结果的正确性。 展开更多
关键词 三维坐标 粗差 总体最小二乘 partial-EIV 数据探测法
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附加一次和二次等式约束的Partial-EIV模型及相应算法 被引量:1
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作者 韩杰 张松林 《测绘科学技术学报》 北大核心 2019年第1期17-22,27,共7页
研究了附加一次和二次等式约束的Partial-EIV模型,推导了加权整体最小二乘估计准则下相应的计算公式,并讨论了仅附加一次等式约束的Partial-EIV模型和仅附加二次等式约束的Partial-EIV模型。通过正交线性回归和平面坐标转换两个算例进... 研究了附加一次和二次等式约束的Partial-EIV模型,推导了加权整体最小二乘估计准则下相应的计算公式,并讨论了仅附加一次等式约束的Partial-EIV模型和仅附加二次等式约束的Partial-EIV模型。通过正交线性回归和平面坐标转换两个算例进行实验,将新算法与已有的附加等式约束的EIV模型的方法进行了对比,发现文中方法计算效率更高,且适用于结构化EIV模型的求解。 展开更多
关键词 整体最小二乘 partial-EIV模型 等式约束 正交线性回归 平面坐标转换
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Acute effects of partial-body vibration in sitting position
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作者 Yannik Faes Nora Banz +4 位作者 Nathalie Buscher Angela Blasimann Lorenz Radlinger Patric Eichelberger Achim Elfering 《World Journal of Orthopedics》 2018年第9期156-164,共9页
AIM To investigate the acute effects of sinusoidal and stochastic resonance partial-body vibration in sitting position, including muscle activity, heart rate variability, balance and flexibility.METHODS Fifty healthy ... AIM To investigate the acute effects of sinusoidal and stochastic resonance partial-body vibration in sitting position, including muscle activity, heart rate variability, balance and flexibility.METHODS Fifty healthy participants were assigned randomly to two training conditions: A sinusoidal partial-body vibration(SIN, 8 Hz) or a stochastic resonance partial-body vibration(STOCH, 8 ± 2 Hz). For baseline assessment participants sat on the vibration platform without vibration. Both training conditions consisted of five series of a one-minute vibration training and a one-minutebreak between them. In this experimental study surface electromyography(EMG) of the erector spinae(ES), one of the back muscles, and heart rate variability(HRV) was measured at baseline and during training. Balance and flexibility were assessed at baseline and immediately after training. Balance was measured with the modified star excursion balance test(mS EBT) and flexibility was assessed through the modified fingertip-to-floor method(mF TF).RESULTS Paired sample t-test showed a significant increase in balance that was restricted to STOCH(t =-2.22, P = 0.018; SIN: t =-0.09, P = 0.466). An increase in flexibility was also restricted to STOCH(t = 2.65, P = 0.007; SIN: t = 1.41, P = 0.086). There was no significant change of muscle activity in the ES-EMG in STOCH or SIN conditions. In both training conditions, HRV decreased significantly, but remained in a low-load range(STOCH: t = 2.89, P = 0.004; SIN: t = 2.55, P = 0.009).CONCLUSION In sitting position, stochastic resonance partial-body vibration can improve balance and flexibility while cardiovascular load is low. STOCH can be a valuable training option to people who are unable to stand(e.g., people, who are temporarily wheelchair-bound). 展开更多
关键词 partial-body VIBRATION Balance FLEXIBILITY Sinusoidal Stochastic resonance
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Partial-SOI high voltage P-channel LDMOS with interface accumulation holes
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作者 吴丽娟 胡盛东 +2 位作者 罗小蓉 张波 李肇基 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期373-378,共6页
A new partial SOI (silion-on-insulator) (PSOI) high voltage P-channel LDMOS (lateral double-diffused metal-oxide semiconductor) with an interface hole islands (HI) layer is proposed and its breakdown character... A new partial SOI (silion-on-insulator) (PSOI) high voltage P-channel LDMOS (lateral double-diffused metal-oxide semiconductor) with an interface hole islands (HI) layer is proposed and its breakdown characteristics are investigated theoretically. A high concentration of charges accumulate on the interface, whose density changes with the negative drain voltage, which increase the electric field (Er) in the dielectric buried oxide layer (BOX) and modulate the electric field in drift region . This results in the enhancement of the breakdown voltage (BV). The values of E1 and BV of an HI PSOI with a 2-~m thick SOI layer over a 1-~tm thick buried layer are 580V/~m and -582 V, respectively, compared with 81.5 V/p.m and -123 V of a conventional PSOI. Furthermore, the Si window also alleviates the self-heating effect (SHE). Moreover, in comparison with the conventional device, the proposed device exhibits low on-resistance. 展开更多
关键词 interface charges breakdown voltage partial-SOI accumulation holes self-heating effect
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FORWARD LINK PARTIAL-BALANCE POWER CONTROL ALGORITHM FOR W-CDMA COMMUNICATION
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作者 Qiu Ling Zhang Lei Zhu Jinkang (PCN&SS Lab. University of Science and Technology of China, Hefei 230027) 《Journal of Electronics(China)》 2000年第1期25-30,共6页
Balance power control is based on the idea of balancing Carrier to Interference Ratio (CIR) of all wireless links. Unbalance power control means that different traffics can achieve different CIR at receivers. This pap... Balance power control is based on the idea of balancing Carrier to Interference Ratio (CIR) of all wireless links. Unbalance power control means that different traffics can achieve different CIR at receivers. This paper proposes a forward link partial-balance power control algorithm, which can provide necessary Quality of Service (QoS) for multimedia traffics in Wideband CDMA(W-CDMA) systems. The proposed algorithm is the integration of grading traffics priority and allocating and adjusting forward link power levels. For higher priority traffics, the unbalance power control is used. Whereas for lower priority traffics, balance power control is adopted. Computer simulation results show that the proposed algorithm can guarantee the special QoS requirements of the traffics with higher priority orders and maximize the CIR of the traffics with lower priority orders. 展开更多
关键词 W-CDMA system FORWARD LINK partial-balance power control
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基于Partial-EIV的数据探测法研究
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作者 王铮尧 梁菲 《中国煤炭地质》 2022年第11期74-78,共5页
为了解决EIV(Errors-In-Variables)模型的粗差问题,在Partial-EIV模型的基础上拓展数据探测法,对Partial-EIV的模型在(a_(0),β_(0))处进行线性展开,变换为最小二乘形式,进一步推导EIV模型下的单位权方差估计值,推导出数据探测法,通过... 为了解决EIV(Errors-In-Variables)模型的粗差问题,在Partial-EIV模型的基础上拓展数据探测法,对Partial-EIV的模型在(a_(0),β_(0))处进行线性展开,变换为最小二乘形式,进一步推导EIV模型下的单位权方差估计值,推导出数据探测法,通过算例分析,在观测值独立等精度情形下,可以有效地发现观测数据中的粗差。 展开更多
关键词 EIV模型 粗差探测 partial-EIV 单位权方差
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Effects of axial gap and nozzle distribution on aerodynamic forces of a supersonic partial-admission turbine 被引量:4
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作者 Jinpeng JIANG Jiawen LI +2 位作者 Guobiao CAI Jue WANG Qiyan LIN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第6期1844-1853,共10页
The turbine in an LH2/LOX rocket engine is designed as a two-stage supersonic partialadmission turbine. Three-dimensional steady and unsteady simulations were conducted to analyze turbine performance and aerodynamic f... The turbine in an LH2/LOX rocket engine is designed as a two-stage supersonic partialadmission turbine. Three-dimensional steady and unsteady simulations were conducted to analyze turbine performance and aerodynamic forces on rotor blades. Different configurations were employed to investigate the effects of the axial gap and nozzle distribution on the predicted performance and aerodynamic forces. Rotor blades experience unsteady aerodynamic forces because of the partial admission. Aerodynamic forces show periodicity in the admission region, and are close to zero after leaving the admission region. The unsteady forces in frequency domain indicate that components exist in a wide frequency region, and the admission passing frequency is dominant.Those multiples of the rotational frequency which are multiples of the nozzle number in a fulladmission turbine are notable components. Results show that the turbine efficiency decreases as the axial gap between nozzles and the 1 st stage rotor(rotor 1) increases. Fluctuation of the circumferential aerodynamic force on rotor 1 blades decreases with the axial gap increasing. The turbine efficiency decreases as the circumferential spacing between nozzles increases. Fluctuations of the circumferential and axial aerodynamic forces increase as the circumferential spacing increases. As for the non-equidistant nozzle distribution, it produces similar turbine performance and amplitudefrequency characteristics of forces to those of the normal configuration, when the mean spacing is equal to that of the normal case. 展开更多
关键词 Aerodynamic force Axial gap Computational fluid dynam-ics (CFD) Nozzle distribution Partial admission TURBINE
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Feasibility of the partial-single arc technique in RapidArc planning for prostate cancer treatment 被引量:1
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作者 Suresh Rana ChihYao Cheng 《Chinese Journal of Cancer》 SCIE CAS CSCD 2013年第10期546-552,共7页
The volumetric modulated arc therapy(VMAT)technique,in the form of RapidArc,is widely used to treat prostate cancer.The full-single arc(f-SA)technique in RapidArc planning for prostate cancer treatment provides effici... The volumetric modulated arc therapy(VMAT)technique,in the form of RapidArc,is widely used to treat prostate cancer.The full-single arc(f-SA)technique in RapidArc planning for prostate cancer treatment provides efficient treatment,but it also delivers a higher radiation dose to the rectum.This study aimed to compare the dosimetric results from the new partial-single arc(p-SA)technique with those from the f-SA technique in RapidArc planning for prostate cancer treatment.In this study,10 patients with lowrisk prostate cancer were selected.For each patient,two sets of RapidArc plans(f-SA and p-SA)were created in the Eclipse treatment planning system.The f-SA plan was created using one full arc,and the p-SA plan was created using planning parameters identical to those of the f-SA plan but with anterior and posterior avoidance sectors.Various dosimetric parameters of the f-SA and p-SA plans were evaluated and compared for the same target coverage and identical plan optimization parameters.The f-SA and p-SA plans showed an average difference of±1%for the doses to the planning target volume(PTV),and there were no clear differences in dose homogeneity or plan conformity.In comparison to the f-SA technique,the p-SA technique reduced the doses to the rectum by approximately 6.1%to 21.2%,to the bladder by approximately 10.3%to 29.5%,and to the penile bulb by approximately 2.2%.In contrast,the dose to the femoral heads,the integral dose,and the number of monitor units were higher in the p-SA plans by approximately 34.4%,7.7%,and 9.2%,respectively.In conclusion,it is feasible to use the p-SA technique for RapidArc planning for prostate cancer treatment.For the same PTV coverage and identical plan optimization parameters,the p-SA technique is better in sparing the rectum and bladder without compromising plan conformity or target homogeneity when compared to the f-SA technique. 展开更多
关键词 治疗计划系统 SA技术 前列腺癌 ECLIPSE 辐射剂量 参数规划 优化参数 剂量分布
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Performance of Luby transform coded frequency hopping systems in partial-band jamming
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作者 卜祥元 邱源 +2 位作者 杨行 周荣花 马园园 《Journal of Beijing Institute of Technology》 EI CAS 2013年第3期367-373,共7页
Luby transform (LT) codes are proposed to suppress the effect of partial band noise jam- ming in frequency hopping (FH) communication systems. A decoding scheme for joint erasures of severely jammed symbols and er... Luby transform (LT) codes are proposed to suppress the effect of partial band noise jam- ming in frequency hopping (FH) communication systems. A decoding scheme for joint erasures of severely jammed symbols and error correction is proposed. If an uncorrectable error is detected, the receiver erases the jammed symbols and uses incremental redundancy to increase the error-correcting capability. The performance of LT codes, under power-oppressive partial band noise jamming ( PB- N J) with the additive white Gaussian noise (AWGN), is evaluated via simulation. Even if the jam- mer spreads its high power over half of the hopping bandwidth, LT codes are shown to achieve a tar- get bit error probability of 10 -5, demonstrating their effectiveness as high-performance codes to im- prove the ability of FH systems to combat varying partial band noise jamming. 展开更多
关键词 Luby transform (LT) codes frequency hopping (FH) erasure-correcting partial bandnoise jamming (PBNJ) anti-jam
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水资源集对分析方法理论与应用研究进展 被引量:2
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作者 金菊良 周亮广 +3 位作者 崔毅 吴成国 周戎星 张礼兵 《水利学报》 北大核心 2025年第1期20-31,共12页
集对分析方法应用同、异、反一分为三辨证思维,处理水资源复杂系统不确定性问题具有独特优势,已成为定量计算与物理解析水资源不确定性问题的重要前沿和研究热点。针对有些集对分析方法的物理解析不清晰、计算公式不统一等问题,结合文... 集对分析方法应用同、异、反一分为三辨证思维,处理水资源复杂系统不确定性问题具有独特优势,已成为定量计算与物理解析水资源不确定性问题的重要前沿和研究热点。针对有些集对分析方法的物理解析不清晰、计算公式不统一等问题,结合文献计量分析,系统总结了近25年来水资源集对分析方法理论和应用研究进展。结果表明:(1)水资源集对分析方法历经移植、耦合、创新三个发展阶段,移植期发展较为缓慢,耦合、创新期中偏联系数、减法集对势等新的伴随函数方法推动水资源集对分析方法不断快速发展。(2)水利、资源和环境科学是目前集对分析方法研究的主要领域,水资源问题综合评价为主要研究热点。(3)伴随函数中减法集对势快速发展为相对独立的重要方向,并与偏联系数、半偏联系数等方法耦合出一系列水资源集对分析新方法,而高阶偏联系数计算、联系熵物理内涵等系列问题仍未形成共识,邻联系数的研究还较少。(4)目前水资源集对评价是热点研究领域,集对预测仍以单要素预测为主,集对决策仍属系统评价范畴,定量化决策和推理模型研究不足。由此,对集对推理等水资源集对分析方法发展趋势进行展望,以期为水资源复杂系统不确定性分析、结构水资源学等发展提供辩证思维和理论方法。 展开更多
关键词 水资源集对分析方法 集对系统 同异反关系 一分为三 辩证关系 集对势 偏联系数 半偏联系数
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基于改进算术优化算法的光伏多峰最大功率点跟踪控制 被引量:2
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作者 刘春喜 黄远航 +2 位作者 周立 李世纪 林枝伟 《电力系统保护与控制》 北大核心 2025年第13期36-46,共11页
局部遮阴条件下光伏阵列的功率-电压特性曲线出现多个峰值,传统最大功率点跟踪(maximum power point tracking, MPPT)技术无法准确追踪到全局最大功率点。针对该问题提出一种基于改进算术优化算法(improved arithmetic optimization alg... 局部遮阴条件下光伏阵列的功率-电压特性曲线出现多个峰值,传统最大功率点跟踪(maximum power point tracking, MPPT)技术无法准确追踪到全局最大功率点。针对该问题提出一种基于改进算术优化算法(improved arithmetic optimization algorithm, IAOA)的MPPT控制方法。首先,采用Sobol序列生成均匀分布的初始种群,增加种群多样性。其次,为了平衡算术优化算法(arithmetic optimization algorithm, AOA)的全局搜索和局部开发能力,对AOA中数学优化器加速函数的权重进行重构。最后,在AOA的位置更新中引入Lévy飞行策略,并将准反向学习用于每次更新后的最佳解,增强了算法的收敛速度和跳出局部最优的能力。仿真和实验结果表明,将改进后的算法应用于MPPT控制中,能够在不同的局部遮阴及光照突变条件下准确、快速地跟踪到全局最大功率点,且功率振荡小。 展开更多
关键词 光伏系统 最大功率点跟踪 局部遮阴 算术优化算法 Lévy飞行
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金针菇野生菌株原生质体单核化和无性孢子单孢分离中出现的核偏分离现象 被引量:1
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作者 王宇 熊惠洋 +3 位作者 杨瑞恒 吴莹莹 刘霞 鲍大鹏 《菌物学报》 北大核心 2025年第5期62-72,共11页
担子菌类食用真菌的同一个细胞里的2个细胞核具有不同的活跃度,会在原生质体单核化和无性孢子单孢分离中出现核偏分离现象。本文首先以15株金针菇野生菌和2株栽培菌为供试材料,采用原生质体单核化的方法分离单核体。结果表明有13株野生... 担子菌类食用真菌的同一个细胞里的2个细胞核具有不同的活跃度,会在原生质体单核化和无性孢子单孢分离中出现核偏分离现象。本文首先以15株金针菇野生菌和2株栽培菌为供试材料,采用原生质体单核化的方法分离单核体。结果表明有13株野生菌(GS0002、GS0049、GS0116、GS0145、GS0169、GS0174、GS0175、GS0180、GS0193、GS0194、GS0196、GS0200、GS0225)和2株栽培菌(T011、T022)在原生质体单核化过程中出现偏分离现象,交配型偏离比例范围为1.9:1–35:0。选取其中5株野生菌,再采用粉孢子单孢分离的方法分离单核。结果表明有4株野生菌(GS0116、GS0169、GS0200、GS0216)在粉孢子单孢分离过程中出现偏分离现象,交配型偏离比例范围为1.7:1–26.5:1。通过杂交亲和性实验,鉴定了两种分离方法中均出现交配型偏分离的3株菌株的强势细胞核和弱势细胞核,结果发现它们的交配型具有一致性(GS116-6与GS0116-107、GS0116-17与GS0116-30、GS0169-2与GS0169-121、GS0169-1与GS0169-79、GS0200-30与GS0200-1、GS0200-21与GS0200-110)。 展开更多
关键词 金针菇 原生质体单核化 粉孢子单孢分离 偏分离 交配型
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怀菊不同部位中8种黄酮含量比较 被引量:1
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作者 李孟 郭梦真 +6 位作者 邓晓颜 张博文 王小兰 刘通 张莉 郑晓珂 冯卫生 《中成药》 北大核心 2025年第2期378-383,共6页
目的测定怀菊花、茎、叶中芹菜素、金合欢素、香叶木素-7-O-β-D-吡喃葡萄糖苷、香叶木素、木犀草素、金合欢素-7-O-β-D-吡喃葡萄糖苷、木犀草苷、芹菜素-7-O-β-D-吡喃葡萄糖苷的含量。方法HPLC法测定58批药材中各黄酮含量,再进行层... 目的测定怀菊花、茎、叶中芹菜素、金合欢素、香叶木素-7-O-β-D-吡喃葡萄糖苷、香叶木素、木犀草素、金合欢素-7-O-β-D-吡喃葡萄糖苷、木犀草苷、芹菜素-7-O-β-D-吡喃葡萄糖苷的含量。方法HPLC法测定58批药材中各黄酮含量,再进行层次聚类分析、主成分分析和正交偏最小二乘判别分析。结果8种黄酮在各部位中均有检出,其含量存在差异,总体上依次为花>叶>茎,香叶木素-7-O-β-D-吡喃葡萄糖苷和芹菜素-7-O-β-D-吡喃葡萄糖苷为差异性成分。结论怀菊花、茎、叶中均含有黄酮,在以前者为主原料的同时应加大后两者的开发利用,以期充分提高该药材经济效益。 展开更多
关键词 怀菊 部位 黄酮 含量测定 HPLC 层次聚类分析 主成分分析 正交偏最小二乘判别分析
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