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Deciphering TADF Mechanisms in Metal-Free Organic Emitters BrA-HBI:Utilizing Optimally Tuned Range-Separated Functionals for Insight
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作者 Chunyue Yu Hang Yin +2 位作者 Jie Guo Wentian Zhang Ying Shi 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期28-37,共10页
Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently... Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently,Shao et al.presented a novel excited state intramolecular proton transfer(ESIPT)system BrA-HBI,demonstrating an emission quantum yield of up to 50%[Adv.Funct.Mater.32,2201256(2022)].However,many open issues cannot be answered solely by experimental means only and require detailed theoretical investigations.For instance,what causes the activation of TADF from the Keto^(*) tautomer and leads to fluorescence quenching in the Enol^(*)form?Herein,we provide a theoretical investigation on the TADF mechanism of the BrA-HBI molecule by optimally tuned range-separated functionals.Our findings reveal that ESIPT occurs in the BrA-HBI molecule.Moreover,we have disclosed the reason for the fluorescence quenching of the Enol^(*)form and determined that the T_(2)state plays a dominant role in the TADF phenomenon.In addition,double hybrid density functionals method was utilized to verify the reliability of optimally tuned range separation functionals on the calculation of the TADF mechanism in BrA-HBI.These findings not only provide a theoretical reference for development of highly efficient organic light-emitting diodes,but also demonstrate the effectiveness of the optimally tuned range-separated functionals in predicting the luminescence properties of TADF molecules. 展开更多
关键词 optimal finding separateD
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Separate-layer balanced waterflooding development technology for thick and complex carbonate reservoirs in the Middle East
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作者 SONG Xinmin LI Yong +6 位作者 LI Fengfeng YI Liping SONG Benbiao ZHU Guangya SU Haiyang WEI Liang YANG Chao 《Petroleum Exploration and Development》 SCIE 2024年第3期661-673,共13页
Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic... Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs. 展开更多
关键词 the Middle East thick carbonate reservoir vertical heterogeneity concealed baffle and barrier sealing separated development units balanced waterflooding
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Pharmacodynamic Experiment of Dachengqi Decoction and Separated Decoction on Incomplete Intestinal Obstruction in Rats
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作者 Jiangcun WEI Xiumei MA +5 位作者 Bing QING Meiyan QIU Qingmei DENG Hong LEI Zengyan YANG Zujie QIN 《Medicinal Plant》 2024年第4期107-110,共4页
[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intesti... [Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intestinal obstruction model by silk ligation.The dosage was 20 mL/kg for 3 d,and the damage index of ileocecal mucosa was analyzed;the morphology of ileocecal mucosa was observed by HE staining;the serum levels of IL-1α,IL-1β,IL-6,IL-18,Ach,NO,ET,IL-1,TNF-αand ultra-micro Na+-K+-ATPase were detected by ELISA.[Results]Compared with the model group,the mucosal damage index of Dachengqi Decoction and each separated decoction group decreased significantly(P<0.05);compared with the normal group and sham operation group,the serum level of IL-1,IL-6,TNF-αand other factors in the model group increased significantly(P<0.05);compared with the model group,the serum IL-1,IL-6 and TNF-αsecretion levels of rats in Dachengqi Decoction group and separated decoction group decreased(P<0.01).[Conclusions]Dachengqi Decoction and each separated decoction can effectively improve intestinal tissue pathological damage in the incomplete intestinal obstruction model rats,and reduce the inflammatory reaction in the rat body. 展开更多
关键词 Dachengqi Decoction separated decoction Incomplete intestinal obstruction Inflammatory factor
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Decoupled thermal–hydraulic analysis of an air-cooled separated heat pipe for spent fuel pools under natural convection 被引量:1
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作者 Hui-Lin Xue Jian-Jie Cheng +3 位作者 Wei-Hao Ji Wen-Jin Li Han-Zhong Tao Wei Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期183-197,共15页
An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal ... An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS. 展开更多
关键词 Decoupled analysis separated heat pipe CAP1400 Finned tube radiator Passive cooling
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Development and prospect of downhole monitoring and data transmission technology for separated zone water injection 被引量:1
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作者 LIU He ZHENG Lichen +4 位作者 YU Jiaqing MING Eryang YANG Qinghai JIA Deli CAO Gang 《Petroleum Exploration and Development》 2023年第1期191-201,共11页
This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptabi... This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development. 展开更多
关键词 separated zone water injection downhole monitoring data transmission cable communication vibration wave pressure wave flow wave
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Deep learning enabled single-shot absolute phase recovery in high-speed composite fringe pattern profilometry of separated objects
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作者 Maciej Trusiak Malgorzata Kujawinska 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第12期1-4,共4页
A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled ... A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled fringe projection profilometry(FPP).In this News&Views article,we explore potential avenues for future advancements,including expanding the measurement range through an extended number-theoretical approach,enhancing quality through the incorporation of horizontal fringes,and integrating data from other modalities to broaden the system's applications. 展开更多
关键词 system ABSOLUTE separateD
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Short- and long-term results of open vs laparoscopic multisegmental resection and anastomosis for synchronous colorectal cancer located in separate segments
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作者 Ji-Chuan Quan Xin-Jun Zhou +8 位作者 Shi-Wen Mei Jun-Guang Liu Wen-Long Qiu Jin-Zhu Zhang Bo Li Yue-Gang Li Xi-Shan Wang Hu Chang Jian-Qiang Tang 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第9期1969-1977,共9页
BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous c... BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous colorectal cancer(SCRC)located in separate segments.AIM To compare the short-term efficacy and long-term prognosis of OMRA as well as LMRA for SCRC located in separate segments.METHODS Patients with SCRC who underwent surgery between January 2010 and December 2021 at the Cancer Hospital,Chinese Academy of Medical Sciences and the Peking University First Hospital were retrospectively recruited.In accordance with the RESULTS LMRA patients showed markedly less intraoperative blood loss than OMRA patients(100 vs 200 mL,P=0.006).Compared to OMRA patients,LMRA patients exhibited markedly shorter postoperative first exhaust time(2 vs 3 d,P=0.001),postoperative first fluid intake time(3 vs 4 d,P=0.012),and postoperative hospital stay(9 vs 12 d,P=0.002).The incidence of total postoperative complications(Clavien-Dindo grade:≥II)was 2.9%and 17.1%(P=0.025)in the LMRA and OMRA groups,respectively,while the incidence of anastomotic leakage was 2.9%and 7.3%(P=0.558)in the LMRA and OMRA groups,respectively.Furthermore,the LMRA group had a higher mean number of lymph nodes dissected than the OMRA group(45.2 vs 37.3,P=0.020).The 5-year overall survival(OS)and disease-free survival(DFS)rates in OMRA patients were 82.9%and 78.3%,respectively,while these rates in LMRA patients were 78.2%and 72.8%,respectively.Multivariate prognostic analysis revealed that N stage[OS:HR hazard ratio(HR)=10.161,P=0.026;DFS:HR=13.017,P=0.013],but not the surgical method(LMRA/OMRA)(OS:HR=0.834,P=0.749;DFS:HR=0.812,P=0.712),was the independent influencing factor in the OS and DFS of patients with SCRC.CONCLUSION LMRA is safe and feasible for patients with SCRC located in separate segments.Compared to OMRA,the LMRA approach has more advantages related to short-term efficacy. 展开更多
关键词 Synchronous colorectal cancer separate segments Laparoscopic surgery Multisegmental resection Short-term efficacy Prognosis
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A Novel Scheme for Separate Training of Deep Learning-Based CSI Feedback Autoencoders
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作者 Lusheng Xi Yanan Yu +5 位作者 Jianzhong Yi Chao Dong Kai Niu Qiuping Huang Qiubin Gao Yongqiang Fei 《Journal of Computer and Communications》 2023年第9期143-153,共11页
In this paper, we introduce a novel scheme for the separate training of deep learning-based autoencoders used for Channel State Information (CSI) feedback. Our distinct training approach caters to multiple users and b... In this paper, we introduce a novel scheme for the separate training of deep learning-based autoencoders used for Channel State Information (CSI) feedback. Our distinct training approach caters to multiple users and base stations, enabling independent and individualized local training. This ensures the more secure processing of data and algorithms, different from the commonly adopted joint training method. To maintain comparable performance with joint training, we present two distinct training methods: separate training decoder and separate training encoder. It’s noteworthy that conducting separate training for the encoder can pose additional challenges, due to its responsibility in acquiring a compressed representation of underlying data features. This complexity makes accommodating multiple pre-trained decoders for just one encoder a demanding task. To overcome this, we design an adaptation layer architecture that effectively minimizes performance losses. Moreover, the flexible training strategy empowers users and base stations to seamlessly incorporate distinct encoder and decoder structures into the system, significantly amplifying the system’s scalability. . 展开更多
关键词 Autoencoder Joint Training separate Training CSI Feedback
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Accurate design of spatially separated double active site in Bi_(4)NbO_(8)Cl single crystal to promote Z-Scheme photocatalytic overall water splitting
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作者 Kailong Gao Hongxia Guo +4 位作者 Yanan Hu Hongbin He Mowen Li Xiaoming Gao Feng Fu 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期568-582,I0014,共16页
The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction wa... The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction was a major challenge.Here,we propose a strategy to accelerate surface water oxidation through the fabrication spatially separated double active sites.FeCoPi/Bi_(4)NbO_(8)Cl-OVs photocatalyst with spatially separated double active site was prepared by hydrogen reduction photoanode deposition method.Due to the high matching of the spatial loading positions of FeCoPi and OVs with the photogenerated charge distribution of Bi_(4)NbO_(8)Cl and corresponding reaction mechanisms of substrate,the FeCoPi and OVs on the(001)and(010)crystal planes of Bi_(4)NbO_(8)Cl photocatalyst provided surface active site for water oxidation reaction and electron shuttle reaction(Fe^(3+)/Fe^(2+)),respectively.Under visible light irradiation,the evolution O_(2)rate of FeCoPi/Bi_(4)NbO_(8)Cl OVs was 16.8μmol h^(-1),as 32.9 times as Bi_(4)NbO_(8)Cl.Furthermore,a hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3)was prepared by sequential photodeposition method.Due to the introduction of Ru,the Schottky barrier between PbTiO_(3)and Pt was effectively reduced,which promoted the transfer of photogenerated electrons to PtRu@Cr_(2)O_(3)thermodynamically,the evolution H_(2)rate on PtRu@Cr_(2)O_(3)/PbTiO_(3)increased to 664.8 times.On based of the synchronous enhancement of the water oxidation performance on FeCoPi/Bi_(4)NbO_(8)Cl-OVs and water reduction performance on PtRu@Cr_(2)O_(3)/PbTiO_(3),a novel Z-Scheme photocatalytic overall water splitting system(FeCoPi/Bi_(4)NbO_(8)Cl-OVs)mediated by Fe^(3+)/Fe^(2+)had successfully constructed.Under visible light irradiation,the evolution rates of H_(2)and O_(2)were 2.5 and 1.3μmol h^(-1),respectively.This work can provide some reference for the design of active site and the controllable synthesis of OVs spatial position.On the other hand,the hydrogen evolution co catalyst(PtRu@Cr_(2)O_(3))and the co catalyst FeCoPi for oxygen evolution contributed to the construction of an overall water splitting system. 展开更多
关键词 Spatially separated double active sites FeCoPi/Bi_(4)NbO_(8)Cl-OVs Photocatalytic water oxidation Photocatalytic hydrogen evolution Hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3) Z-Scheme photocatalytic overall water splitting system
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Investigation of the interaction between NS-DBD plasma-induced vortexes and separated flow over a swept wing
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作者 刘备 梁华 郑博睿 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期88-99,共12页
The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and... The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and separated flow.In order to study the mechanism of NS-DBD plasma flow separation control over a swept wing,especially the influence of the actuation frequency,at first,experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation method.Then,numerical studies of different actuation frequencies which are 50 Hz,100 Hz,160 Hz,200 Hz,500 Hz,and 1000 Hz,respectively are conducted.The interaction between the plasma-induced vortexes and the separated flow is analyzed.Results show that there is a range of the actuation frequency which includes the frequency(160 Hz) calculated by the average aerodynamic chord length to make the control effect good,but when the actuation frequencies are too low(50 Hz) or too high(1000 Hz),the control effect will get worse.The former is because plasmainduced vortexes disappear in a period within an actuation cycle;the latter is because plasma-induced vortexes cannot develop completely,resulting in a weak vortex intensity. 展开更多
关键词 plasma-induced vortex flow separation control NS-DBD LES
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Separate支架在治疗胃十二指肠恶性梗阻中的应用 被引量:3
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作者 何旭 顾建平 +6 位作者 楼文胜 陈亮 苏浩波 Ji-Hoon Shin Jin-Oh Lim Tae-Hyuang Kim Ho-Young Song 《介入放射学杂志》 CSCD 2003年第6期431-435,共5页
目的 探讨Separate支架置入术在姑息性治疗不能手术的胃肠道恶性梗阻的可行性和有效性。方法  34例患者采用经口置入Separate支架治疗不能手术的恶性胃十二指肠梗阻。梗阻的原因分别是胃癌 1 1例、胰腺癌 1 2例、转移性肿瘤 3例、胆... 目的 探讨Separate支架置入术在姑息性治疗不能手术的胃肠道恶性梗阻的可行性和有效性。方法  34例患者采用经口置入Separate支架治疗不能手术的恶性胃十二指肠梗阻。梗阻的原因分别是胃癌 1 1例、胰腺癌 1 2例、转移性肿瘤 3例、胆道肿瘤 6例和十二指肠癌 2例。透视下分别将Separate支架的外层带膜支架和内层裸支架同轴重叠释放在狭窄病变处。结果 技术成功率为 97% ,未发生严重并发症。 33例患者胃肠道梗阻症状缓解或消失 ,在Separate支架置入后 ,患者进食能力评分平均从 3.8提高到 1 .2。随访期间未发现支架移位和肿瘤内生性生长等并发症 ,1例患者由于肿瘤浸润致支架近端梗阻复发 ,置入第 2枚支架。 展开更多
关键词 separate支架 胃十二指肠恶性梗阻 支架置入术 钡餐检查 介入治疗
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强磁场条件下的spatial separated D^-心
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作者 邢雁 王旭 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期520-526,共7页
采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多... 采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多电子效应 ,发现 D-s 心的本征能量随朗道能级填充因子作周期性振荡 ,且随着温度的降低振荡加剧 ;当填充因子为偶数时 ,其本征能量的绝对值最大 ,说明此时电子气对库仑势的屏蔽效应最弱 . 展开更多
关键词 SPATIAL separateD D^-心 强磁场 束缚态 多电子效应 对角化法 量子阱 哈密顿量
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SEPARATED FRAMES
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作者 张凤玲 StraussDona 《Transactions of Tianjin University》 EI CAS 1998年第1期76-79,共4页
In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the ... In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the T O space X being Hausdorff. The class of separated frames includes that of strong Hausdorff frames and that of S frames. We shall show that the class of separated frames is a class closed under the formation of coproducts and subspaces, and the space Fil( L ) is Hausdorff for any separated frame L . Therefore there is a contravariant adjunction between the category TOP 2 of Hausdorff topological spaces and the category FRAM 2 of separated frames. 展开更多
关键词 FRAME separated frame Hausdorff topological space adjunction between categories
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P-and S-wavefield simulations using both the firstand second-order separated wave equations through a high-order staggered grid finite-difference method
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作者 Chao-ying Bai Xin Wang Cai-xia Wang 《Earthquake Science》 2013年第2期83-98,共16页
In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this... In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this, especially when the velocity field is complex. A useful approach in multi-component analysis and modeling is to directly solve the elastic wave equations for the pure P- or S-wavefields, referred as the separate elastic wave equa- tions. In this study, we compare two kinds of such wave equations: the first-order (velocity-stress) and the second- order (displacement-stress) separate elastic wave equa- tions, with the first-order (velocity-stress) and the second- order (displacement-stress) full (or mixed) elastic wave equations using a high-order staggered grid finite-differ- ence method. Comparisons are given of wavefield snap- shots, common-source gather seismic sections, and individual synthetic seismogram. The simulation tests show that equivalent results can be obtained, regardless of whether the first-order or second-order separate elastic wave equations are used for obtaining the pure P- or S-wavefield. The stacked pure P- and S-wavefields are equal to the mixed wave fields calculated using the corre- sponding first-order or second-order full elastic wave equations. These mixed equations are computationallyslightly less expensive than solving the separate equations. The attraction of the separate equations is that they achieve separated P- and S-wavefields which can be used to test the efficacy of wave decomposition procedures in multi-com- ponent processing. The second-order separate elastic wave equations are a good choice because they offer information on the pure P-wave or S-wave displacements. 展开更多
关键词 Finite-difference method Staggeredgrid First-order separate elastic wave equation Second-order separate elastic wave equation Multiple arrival tracking
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一个改进的Separate算法及其应用 被引量:1
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作者 王光 唐恒永 《辽宁大学学报(自然科学版)》 CAS 2004年第4期342-345,共4页
关联规则的挖掘是一个重要的数据挖掘问题,在关联规则的挖掘过程中加入约束条件,是实现用户参与挖掘的一种方式,这样得到的规则是用户所真正关心的,而Separate算法便是这类算法的代表.先对Separate算法进行了改进,从而进一步提高其性能... 关联规则的挖掘是一个重要的数据挖掘问题,在关联规则的挖掘过程中加入约束条件,是实现用户参与挖掘的一种方式,这样得到的规则是用户所真正关心的,而Separate算法便是这类算法的代表.先对Separate算法进行了改进,从而进一步提高其性能,然后用改进后的算法挖掘实际应用中的一个实例,最后对挖掘结果给出相关决策解释. 展开更多
关键词 关联规则 项约束 separate算法 jion函数
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Comparative assessment of SAS and DES turbulence modeling for massively separated flows 被引量:4
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作者 Weilin Zheng Chao Yan +1 位作者 Hongkang Liu Dahai Luo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期12-21,共10页
Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached edd... Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached eddy simu- lation (DES), in comparison with the existing experimental data. The new version of the model developed by Egorov and Menter is assessed, and advantages and disadvantages of the SAS simulation are analyzed in detail to provide guidance for industrial application in the future. Moreover, the mechanism of the scale-adaptive characteristics in separated regions is discussed, which is obscure in previous analyses. It is con- cluded that: the mean flow properties satisfactorily agree with the experimental results for the SAS simulation, although the prediction of the second order turbulent statistics in the near wake region is just reasonable. The SAS model can produce a larger magnitude of the turbulent kinetic energy in the recir- culation bubble, and, consequently, a smaller recirculation region and a more rapid recovery of the mean velocity out- side the recirculation region than the DES approach with the same grid resolution. The vortex shedding is slightly less irregular with the SAS model than with the DES approach, probably due to the higher dissipation of the SAS simulation under the condition of the coarse mesh. 展开更多
关键词 Scale-adaptivelength scale Bluff bodies SIMULATION von Karman Massively separated flows Computational fluid dynamics
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Solving mKdV-sinh-Gordon equation by a modified variable separated ordinary differential equation method 被引量:4
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作者 谢元喜 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5123-5132,共10页
By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact sol... By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact solutions including some new formal solutions are successfully picked up for the mKdV-sinh-Gordon equation by this approach. 展开更多
关键词 modified variable separated ODE method mKdV-sinh-Gordon equation explicit andexact solution
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SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE SEPARATED AND LONG POLY(ETHYLENE OXIDE) SIDE CHAIN STRUCTURES 被引量:4
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作者 邱永兴 俞小洁 +1 位作者 封麟先 杨士林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第1期67-75,共9页
Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (e... Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (ethylene oxide)graft copolymer containing both microphase separated and PEO side chain structures has been synthesized from radical copolymerization of PEO-A macromonomer with styrene. After careful purification by a newly-developed method called 'selective dissolution', the well-defined structure of the purified copolymers was confirmed by IR, ~1H-NMR and GPC. Various experimental parameters controlling the copolymerization were studied in detail. The results indicated that the feed ratio of styrene to macromonomer(S/M) was the most important determining factor for the composition of the copolymers. A detailed 'comb- model' was proposed to describe the molecular structure of the graft copolymers. Finally, this amphiphilic graft copolymers may readily form microphase separated structures as clearly indicated by transmission electron microscopy. 展开更多
关键词 PEO AIBN SIDE CHAIN STRUCTURES SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE separateD AND LONG POLY ETHYLENE OXIDE PS
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Maneuvering target state estimation based on separate model-ing of target trajectory shape and dynamic characteristics 被引量:2
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作者 ZHANG Zhuanhua ZHOU Gongjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第5期1195-1209,共15页
The state estimation of a maneuvering target,of which the trajectory shape is independent on dynamic characteristics,is studied.The conventional motion models in Cartesian coordinates imply that the trajectory of a ta... The state estimation of a maneuvering target,of which the trajectory shape is independent on dynamic characteristics,is studied.The conventional motion models in Cartesian coordinates imply that the trajectory of a target is completely determined by its dynamic characteristics.However,this is not true in the applications of road-target,sea-route-target or flight route-target tracking,where target trajectory shape is uncoupled with target velocity properties.In this paper,a new estimation algorithm based on separate modeling of target trajectory shape and dynamic characteristics is proposed.The trajectory of a target over a sliding window is described by a linear function of the arc length.To determine the unknown target trajectory,an augmented system is derived by denoting the unknown coefficients of the function as states in mileage coordinates.At every estimation cycle except the first one,the interaction(mixing)stage of the proposed algorithm starts from the latest estimated base state and a recalculated parameter vector,which is determined by the least squares(LS).Numerical experiments are conducted to assess the performance of the proposed algorithm.Simulation results show that the proposed algorithm can achieve better performance than the conventional coupled model-based algorithms in the presence of target maneuvers. 展开更多
关键词 maneuvering target tracking separate modeling natural parametric function interacting multiple model(IMM)filter data fitting state augmentation
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Optimal design of the separate type heat pipe heat exchanger 被引量:2
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作者 俞自涛 胡亚才 岑可法 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第B08期23-28,共6页
Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations... Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations have to be carried out separately, which makes it very complicated. In this work, the ε-NTU (effectiveness-Number of Transfer Units) method was applied for optimization analysis of single- or multi-level separate type heat pipe heat exchangers. An optimizing formula for single-level separate type heat pipe heat exchangers was obtained. The optimizing principles of effec- tiveness-NTU and heat transfer rate by the equal distribution method for multi-level separate type heat pipe heat exchanger are presented. The design of separate type heat pipe heat exchangers by the optimizing method is more convenient and faster than by the traditional method. 展开更多
关键词 separate type heat pipe heat exchanger Optimal design ε-NTU (effectiveness-Number of Transfer Units)
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