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Degradation of ciprofloxacin hydrochloride in a multiphase mixed system by subaquatic gas-liquid discharge plasma
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作者 Mengyu WANG Jianping LIANG +5 位作者 Ke LU Zikai ZHOU Qinghua LIU Hao YUAN Wenchun WANG Dezheng YANG 《Plasma Science and Technology》 SCIE EI CAS 2024年第11期144-151,共8页
In recent years, antibiotic pollution has become a serious threat to human health. In this study, a gas-liquid discharge plasma is developed to degrade ciprofloxacin hydrochloride in a multiphase mixed system containi... In recent years, antibiotic pollution has become a serious threat to human health. In this study, a gas-liquid discharge plasma is developed to degrade ciprofloxacin hydrochloride in a multiphase mixed system containing inorganic and organic impurities. The discharge characteristics are analyzed by diagnosing the applied voltage and discharge current waveforms, as well as the optical emission spectra. The work investigates how degradation efficiency is affected by applied voltage, gas flow rate, treatment time, initial concentration as well as the addition of γ-Al_(2)O_(3) pellets and peanut straw. After 70 min, the degradation efficiency of ciprofloxacin hydrochloride in the multiphase mixed system reached 99.6%. Its removal efficiency increases as the initial concentration decreases and the applied voltage increases. Besides, there is still a good degradation efficiency of ciprofloxacin hydrochloride with the addition of peanut straw.The degradation mechanism of ciprofloxacin hydrochloride is investigated through the analysis of degraded intermediates and reactive species. 展开更多
关键词 antibiotic gas-liquid discharge multiphase mixed system ciprofloxacin hydrochloride degradation
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Synergistic anionic/zwitterionic mixed surfactant system with high emulsification efficiency for enhanced oil recovery in low permeability reservoirs 被引量:1
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作者 Hai-Rong Wu Rong Tan +6 位作者 Shi-Ping Hong Qiong Zhou Bang-Yu Liu Jia-Wei Chang Tian-Fang Luan Ning Kang Ji-Rui Hou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期936-950,共15页
Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant... Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs. 展开更多
关键词 Anionic/zwitterionic mixed surfactant system EMULSIFICATION Synergistic effect Low permeability reservoir Enhanced oil recovery
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Impacts of bus holding strategy on the performance and pollutant emissions of a two-lane mixed traffic system
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作者 Yanfeng Qiao Ronghan Yao +1 位作者 Baofeng Pan Yu Xue 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期236-248,共13页
This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissio... This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissions of passenger cars.The dynamic behaviors of these two types of vehicles are described using cellular automata(CA)models under open boundary conditions.Numerical simulations are carried out to obtain the phase diagrams of the bus system and the trajectories of buses and passenger cars before and after the implementation of the bus holding strategy under different probabilities of passenger cars entering a two-lane mixed traffic system.Then,we analyze the flow rate,satisfaction rate,and pollutant emission rates of passenger cars together with the performance of a mixed traffic system.The results show that the bus holding strategy can effectively alleviate bus bunching,whereas it has no significant impact on the flow rate and pollutant emission rates of passenger cars;the flow rate,satisfaction rate,and pollutant emission rates of passenger cars for either the traffic system or for each lane are influenced by the bus departure interval and the number of passengers arriving at bus stops. 展开更多
关键词 mixed traffic flow bus holding strategy cellular automata traffic emissions
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Reliability Analysis of a Mixed Redundant Model in C 3I System 被引量:1
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作者 徐勇 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期324-330,共7页
Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute s... Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute system. The reliability and availability equations of MRM were deduced. Results and Conclusion Compared with several other reliability models, it has obvious effect upon improving the system reliability. The effect? cost rate is very high among these models. The model can be used in reliability design, evaluation and check of C 3I system. Only a little attached cost is needed to improve C 3I system reliability effectively. 展开更多
关键词 C 3I system reliability analysis mixed redundant model
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Middle Permian Mixed Siliciclastic-Carbonate System on the Northwestern Margin of the Indian Plate,Pakistan:Implications for Paleoclimate and Carbonate Platform Evolution 被引量:2
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作者 Bilal WADOOD Suleman KHAN LI Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第1期321-336,共16页
A mixed siliciclastic-carbonate system that responds to changes in Permian climate and subsequent carbonate platform evolution is investigated using microscopic details of the Middle Permian Amb Formation(Fm.),in Saiy... A mixed siliciclastic-carbonate system that responds to changes in Permian climate and subsequent carbonate platform evolution is investigated using microscopic details of the Middle Permian Amb Formation(Fm.),in Saiyiduwali section,Khisor Range,northern Pakistan.Thin sections were made from rocks throughout the stratigraphic section of the Amb Fm.and analyzed with an emphasis on carbonate and clastic microfacies,and the latter interpreted within the existing chronostratigraphic framework.Outcrop observations reveal that the units comprise coarse-grained,channelized,ripplemarked,and burrowed sandstone and sandy,fossiliferous limestone with minor marls and shale intercalations,suggesting deposition in a subaqueous tide-dominated delta to beach barrier.Based on the determined seven microfacies coupled with outcrop observation,the Amb Fm.was deposited in a tide-influenced subaqueous delta to middle shelf environment under fluctuating sea level.The deposition of compositionally mature sandstone in the lower part of the formation suggests reworking of detritus from the rift shoulders and an adjacent source area with an ambient warm and humid climate.The stratal mixing of carbonates and compositionally mature siliciclastic units in the middle part suggest deposition under tectonic and climate-induced terrigenous and carbonate fluxes to the basin.Thus the deposition shows a perfect transition from clastic-dominated deltaic to pure carbonate platform settings as a result of warm climate and tectonics.This Middle Permian warming is confirmed by sea-level rise and the presence of a temperature-sensitive fusulinid fauna in association with photozoan-based ooids.Deposition of the Amb Fm.and establishment of a carbonate platform are envisaged to be associated with major rifting of northern Gondwana,which subsequently resulted in the development of a rift basin at the passive margin of the NW Indian Plate then in northern Pakistan. 展开更多
关键词 SEDIMENTOLOGY RIFTING PALEOCLIMATE siliciclastic-carbonate mixed system Guadalupian/Wordian Khisor Range
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Iterative Solution for Systems of Binary Non-mixed Monotone Operator Equations 被引量:2
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作者 左秀会 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期80-83,共4页
With using the cone and partial ordering t heory and mixed monotone operator theory, the existence and uniqueness for solut ion of systems of non-monotone binary nonliear operator equations are discussed. And the it... With using the cone and partial ordering t heory and mixed monotone operator theory, the existence and uniqueness for solut ion of systems of non-monotone binary nonliear operator equations are discussed. And the iterative sequences which converge to solution of systems of operator e quations and the error estimates are also given. Some corresponding results for the mixed monotone operations and the unary operator equations are improved and generalized. 展开更多
关键词 binary operator mixed monotone operators syste ms of equations SOLUTIONS cone and partial ordering
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Positive Periodic Solutions for Three Species Lotka-Volterra Mixed Ecosystems with Periodic Stocking
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作者 LiBi-werl ZhengLu-zhou 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期779-785,共7页
By using a new method, a set of easily verifiable sufficient conditions are derived for the existence of positive periodic solutions for three\|species Lotka\|Volterra mixed systems with periodic stocking:x 1′(t)=x ... By using a new method, a set of easily verifiable sufficient conditions are derived for the existence of positive periodic solutions for three\|species Lotka\|Volterra mixed systems with periodic stocking:x 1′(t)=x 1(t)(b 1(t)-a 11 (t)x 1(t)-a 12 (t)x 2(t)-a 13 (t)x 3(t))+S 1(t) x 2′(t)=x 2(t)(-b 2(t)+a 21 (t)x 1(t)-a 22 (t)x 2(t)-a 23 (t)x 3(t))+S 2(t) x 3′(t)=x 3(t)(-b 3(t)+a 31 (t)x 1(t)-a 32 (t)x 2(t)-a 33 (t)x 3(t))+S 3(t)where b i(t),a ij (t)(i,j=1,2,3) are positive continuous T \|periodic functions, S i(t)(i=1,2,3) are nonnegative continuous T \|periodic functions. 展开更多
关键词 positive periodic solution Lotka\|Volterra mixed system periodic stocking
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An in situ ATR-FTIR study of mixed collectors BHA/DDA adsorption in ilmenite-titanaugite flotation system 被引量:19
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作者 Liping Luo Houqin Wu +5 位作者 Longhua Xu Jinping Meng Jiahui Lu Huan Zhou Xiaomei Huo Lingyun Huang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第4期689-697,共9页
This paper researched the enhanced flotation separation performance of ilmenite and titanaugite using the mixed collector benzhydroxamic acid/dodecylamine(BHA/DDA).The interface assembly mechanism was mainly investiga... This paper researched the enhanced flotation separation performance of ilmenite and titanaugite using the mixed collector benzhydroxamic acid/dodecylamine(BHA/DDA).The interface assembly mechanism was mainly investigated through in situ attenuated total reflectance Fourier transform infrared(ATRFTIR)spectroscopy combined with the two-dimensional correlation spectroscopy(2D-COS)and X-ray photoelectron spectroscopy(XPS).It has been found that BHA/DDA mixed collectors successfully separate ilmenite from titanaugite at a molar ratio of 8:1.Zeta potential experiments suggested that,in the presence of mixed collector system,the BHA-DDA complex adsorbed on the ilmenite surface via the chemically adsorbed BHA and the electrostatically adsorbed DDA,however,the complex adsorbed on the surface of titanaugite unstably.According to in situ ATR-FTIR combined with 2D-COS and XPS results,the interface assembly mechanism of BHA/DDA is summarized as:the function group of BHA molecules first binds to the metal sites on minerals to form bidentate ligand,then DDA co-adsorbed with BHA on the surface of minerals through hydrogen bonding.DDA may change the adsorption modes of some BHA on the ilmenite surface from four-membered ring to five-membered ring,while the modes on the titanaugite surface is true opposite.Finally,recommended adsorption configurations of the BHA/DDA complex on the two mineral surfaces are proposed. 展开更多
关键词 ILMENITE Titanaugite mixed collector FLOTATION ADSORPTION
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Mixed neuroendocrine-non-neuroendocrine neoplasms of the digestive system:A mini-review 被引量:8
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作者 Deepak Toor Jonathan M Loree +2 位作者 Zu-Hua Gao Gang Wang Chen Zhou 《World Journal of Gastroenterology》 SCIE CAS 2022年第19期2076-2087,共12页
Mixed neuroendocrine-non-neuroendocrine neoplasms(MiNENs)are rare mixed tumors containing both neuroendocrine(NE)and non-NE components.Each component must occupy at least 30%of the tumor volume by definition.Recent mo... Mixed neuroendocrine-non-neuroendocrine neoplasms(MiNENs)are rare mixed tumors containing both neuroendocrine(NE)and non-NE components.Each component must occupy at least 30%of the tumor volume by definition.Recent molecular evidence suggests MiNENs are clonal neoplasms and potentially harbor targetable mutations similar to conventional carcinomas.There have been multiple changes in the nomenclature and classification of MiNENs which has created some confusion among pathologists on how to integrate the contributions of each component in a MiNEN,an issue which in turn has resulted in confusion in communication with front-line treating oncologists.This mini review summarizes our current understanding of MiNENs and outline diagnosis,prognosis,and management of these neoplasms.The authors emphasize the importance of treating the most aggressive component of the tumor regardless of its percentage volume. 展开更多
关键词 mixed neuroendocrine non-neuroendocrine neoplasms mixed adenoneuorendocrine carcinoma mixed neuroendocrine neoplasms NEUROENDOCRINE Non-neuroendocrine
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Mixed epithelial endocrine neoplasms of the colon and rectum–An evolution over time:A systematic review 被引量:7
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作者 Rani Kanthan Suresh Tharmaradinam +2 位作者 Tehmina Asif Shahid Ahmed Selliah C Kanthan 《World Journal of Gastroenterology》 SCIE CAS 2020年第34期5181-5206,共26页
BACKGROUND Mixed tumors of the colon and rectum,composed of a combination of epithelial and endocrine elements of benign and malignant potential are rare neoplasms.These can occur anywhere in the gastrointestinal trac... BACKGROUND Mixed tumors of the colon and rectum,composed of a combination of epithelial and endocrine elements of benign and malignant potential are rare neoplasms.These can occur anywhere in the gastrointestinal tract and are often diagnosed incidentally.Though they have been a well-documented entity in the pancreas,where the exocrine-endocrine mixed tumors have been known for a while,recognition and accurate diagnosis of these tumors in the colon and rectum,to date,remains a challenge.This is further compounded by the different terminologies that have been attributed to these lesions over the years adding to increased confusion and misclassification.Therefore,dedicated literature reviews of these lesions in the colon and rectum are inconsistent and are predominantly limited to case reports and case series of limited case numbers.Though,most of these tumors are high grade and of advanced stage,intermediate and low grade lesions of these mixed tumors are also increasingly been reported.There are no established independent consensus based guidelines for the therapeutic patient management of these unique lesions.AIM To provide a comprehensive targeted literature review of these complex mixed tumors in the colon and rectum that chronicles the evolution over time with summarization of historical perspectives of terminology and to further our understanding regarding their pathogenesis including genomic landscape,clinicoradiological features,pathology,treatment,prognosis,the current status of the management of the primary lesions,their recurrences and metastases.METHODS A comprehensive review of the published English literature was conducted using the search engines PubMed,MEDLINE and GOOGLE scholar.The following search terms[“mixed tumors colon”OR mixed endocrine/neuroendocrine tumor/neoplasm/lesion colon OR adenocarcinoma and endocrine/neuroendocrine tumor colon OR mixed adenocarcinoma and endocrine/neuroendocrine carcinoma colon OR Amphicrine tumors OR Collision tumors]were used.Eligibility criteria were defined and all potential relevant items,including full articles and/or abstracts were independently reviewed,assessed and agreed upon items were selected for in-depth analysis.RESULTS In total 237 full articles/abstracts documents were considered for eligibility of which 45 articles were illegible resulting in a total of 192 articles that were assessed for eligibility of which 139 have been selected for reference in this current review.This seminal manuscript is a one stop article that provides a detailed outlook on the evolution over time with summarization of historical perspectives,nomenclature,clinicoradiological features,pathology,treatment,prognosis and the current status of the management of both the primary lesions,their recurrences and metastases.Gaps in knowledge have also been identified and discussed.An important outcome of this manuscript is the justified proposal for a new,simple,clinically relevant,non-ambiguous terminology for these lesions to be referred to as mixed epithelial endocrine neoplasms(MEENs).CONCLUSION MEEN of the colon and rectum are poorly understood rare entities that encompass an extensive range of heterogeneous tumors with a wide variety of combinations leading to tumors of high,intermediate or low grade malignant potential.This proposed new revised terminology of MEEN will solve the biggest hurdle of confusion and misclassification that plagues these rare unique colorectal neoplasms thus facilitating the future design of multi institutional prospective randomized controlled clinical trials to develop and evaluate newer therapeutic strategies that are recommended for continued improved understanding and personal optimization of clinical management of these unique colorectal neoplasms. 展开更多
关键词 mixed epithelial endocrine neoplasms mixed adeno-neuroendocrine carcinoma mixed adeno neuro endocrine tumors mixed neuroendocrine-non neuroendocrine neoplasms Colorectal
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Tracking Performance of Electric Power Steering System Based on the Mixed H_2/H_∞ Strategy 被引量:10
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作者 ZHAO Wanzhong SHI Guobiao +1 位作者 LIN Yi NIE Hong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期584-590,共7页
The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering (EPS) system. Bad tracking performance will cause assistant torque delay, and make road ... The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering (EPS) system. Bad tracking performance will cause assistant torque delay, and make road feeling bad, and is influenced by the input steering torque and system measuring noise. However the existing methods have some shortages on system's robust dynamic performance and robust stability. The mixed H2/H∞ strategy for recirculating ball-type EPS system in a pure electric bus is proposed, and vehicle dynamic model of the system is established. Due to the existence of system model uncertainty, disturbance signals, sensor noises and the demand of system dynamic performance, the indexes of robust performance and road feeling for drivers are defined as the appraisal control objectives. The H∞ method is introduced to design the H∞ controller, and the H2 method is applied to optimize the H∞ controller, thus the mixed H2/H∞ controller is designed. The response of EPS system to the motor current command with amplitude of 20 A, the road disturbance with amplitude of 500 N and the sensor random noise with the amplitude of 1 A is simulated. The simulation results show that the recirculating ball-type EPS system with the mixed H2/H∞ controller can attenuate the random noises and disturbances and track the boost curve well, so the mixed H2/H∞ controller can improve the system's robust performance and dynamic performance. For the purpose of verifying the performance of the designed control strategy, the motor current tracking performance ground tests are conducted with step response input of the steering wheel, double-lane steering test and lemniscate steering test, respectively. The tests show that the mixed H2/H∞ controller for the recirculating ball-type EPS system of pure electric bus is feasible. The designed controller can solve the robust performance and robust stability of the system, thus improve the tracking performance of the EPS system and provide satisfied road feeling for the drivers. 展开更多
关键词 recirculating ball-type electrical power steering (EPS) system tracking performance mixed H2/H∞
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ON THE EXISTENCE AND UNIQUENESS THEOREMS OF SOLUTIONS FOR THE SYSTEMS OF MIXED MONOTONE OPERATOR EQUATIONS WITH APPLICATIONS 被引量:11
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作者 张石生 郭伟平 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第1期1-14,共14页
The existence, uniqueness and non-symmetric iterative approximation of solutions for a class of systems of mixed monotone operator equations are discussed. As an application, we utilize, the results presented in this ... The existence, uniqueness and non-symmetric iterative approximation of solutions for a class of systems of mixed monotone operator equations are discussed. As an application, we utilize, the results presented in this paper to study the existence and uniqueness problems of common solutions for a class of systems of functional equations arising in dynamic programming of multistage decision processes and a class of systems of nonlinear integral equation. The results obtained in this paper not only answer an open question suggested in [3] but also generalize the corresponding results of [1],[2]. 展开更多
关键词 mixed Monotone Operator Non-symmetric Iteration system of Functional Equations
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Mixed neuroendocrine–nonneuroendocrine neoplasms of the gastrointestinal system:An update 被引量:4
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作者 Gulsum Ozlem Elpek 《World Journal of Gastroenterology》 SCIE CAS 2022年第8期794-810,共17页
Mixed neuroendocrine-nonneuroendocrine neoplasms(Mi NENs)of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment.Over the years,the diagnostic c... Mixed neuroendocrine-nonneuroendocrine neoplasms(Mi NENs)of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment.Over the years,the diagnostic criteria,classification,and clinical behavior of these tumors have been the subjects of ongoing debate,and the various changes in their nomenclature have strengthened the challenges associated with Mi NENs.This review is performed to provide an understanding of the key factors involved in the evolution of the designation of these tumors as Mi NEN,highlight the current diagnostic criteria,summarize the latest data on pathogenesis and provide information on available treatments.Moreover,this work seeks to increase the awareness about these rare neoplasms by presenting the clinicopathological features and prognostic factors that play important roles in their behavior and discussing their different regions of origin in the gastrointestinal system(GIS).Currently,the Mi NEN category also includes tumors in the GIS with a nonneuroendocrine component and epithelial tumors other than adenocarcinoma,depending on the organ of origin.Diagnosis is based on the presence of both morphological components in more than 30%of the tumor.However,this value needs to be reconfirmed with further studies and may be a limiting factor in the diagnosis of Mi NEN by biopsy.Furthermore,available clinicopathological data suggest that the inclusion of amphicrine tumors in the definition of Mi NEN is not supportive and warrants further investigation.The diagnosis of these tumors is not solely based on immunohistochemical findings.They are not hybrid tumors and both components can act independently;thus,careful grading of each component separately is required.In addition to parameters such as the metastatic state of the tumor at the time of diagnosis and the feasibility of surgical resection,the aggressive potential of both components has paramount importance in the choice of treatment.Regardless of the organ of origin within the GIS,almost Mi NENs are tumors with poor prognosis and are frequently encountered in the elderly and men.They are most frequently reported in the colorectum,where data from molecular studies indicate a monoclonal origin;however,further studies are required to provide additional support for this origin. 展开更多
关键词 mixed neuroendocrine–nonneuroendocrine neoplasms mixed adeno neuroendocrine carcinoma Gastrointestinal system LIVER PANCREAS GALLBLADDER
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Simulation and Implementation of Structure and Growth Visualization System of Artificial Mixed Stand
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作者 彭菲 张怀清 卢康宁 《Agricultural Science & Technology》 CAS 2012年第2期449-452,共4页
[Objective] The objective of this paper was to study the simulation and implementation of structure and growth visualization system of artificial mixed stand. [Method] The mixed stand structure visualization model and... [Objective] The objective of this paper was to study the simulation and implementation of structure and growth visualization system of artificial mixed stand. [Method] The mixed stand structure visualization model and growth visualization model were built on the base of the characteristics of mixed stand structure and the relationship between growth and environment; and the C# language and MOGRE graphics engine were used to establish the mixed stand structure and growth visualization system. [Result] The mixed stand structure visualization model and growth visualization model were built, as well as the mixed stand structure and growth visualization system. [Conclusion] This paper realized the visualization simulation of the mixed stand structure and growth. 展开更多
关键词 VISUALIZATION Artificial mixed stand Structure and growth
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Mixed Gl2/GH2 multi-channel multi-objective control synthesis for discrete time systems 被引量:5
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作者 颜文俊 张森林 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期827-834,共8页
This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalized l2 (Gl2) and generalized H2 (GH2) conditions to a set of new linear matrix inequality (LMI) constra... This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalized l2 (Gl2) and generalized H2 (GH2) conditions to a set of new linear matrix inequality (LMI) constraints based on a new stability condition. A technique for variable parameterization is introduced to the multi-objective control problem to preserve the linearity of the synthesis variables. Consequently, the multi-channel multi-objective mixed Gl2/GH2 control problem can be solved less conservatively using computationally tractable algorithms developed in the paper. 展开更多
关键词 mixed Gl2/GH2 synthesis Multi-objective optimization Robust control Discrete linear time-invariant systems G-shaping paradigm
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Temperature-resistant and salt-tolerant mixed surfactant system for EOR in the Tahe Oilfield 被引量:3
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作者 Ji-Xiang Guo Shi-Ling Zhang +4 位作者 Yu-Qi Yang Zi-Jing Yu Liang Li Yu-Shan Wang Long-Sheng Zhang 《Petroleum Science》 SCIE CAS CSCD 2021年第2期667-678,共12页
A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,th... A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,the formation water and rock components in the Tahe Oilfield,the long-term thermal stability,salt tolerance and the ability to change the wettability,interfacial activity and oil washing efficiency of the mixed surfactant system were studied.The system contains the anionic surfactant SDB and another cationic surfactant SDY.When the total mass concentration of the SS solution is 0.15 wt%,m(SDB)/m(SDY)ratio is 1 to 1,and excellent efficiencies are achieved for oil washing for five kinds of Tahe Oilfield crude oils(more than 60%).In addition,after adding cationic surfactant,the adsorption capacity of the surfactant is further reduced,reaching 0.261 mg/g.The oil displacement experiments indicate that under a temperature of 150°C and a salinity of 24.6×104 mg/L,the SS system enhances the oil recovery by over 10%after water flooding.The SS anionic–cationic surfactant system is first presented in the open literature that can be successfully applied to obtain predictions of Tahe Oilfield carbonate reservoirs with a high temperature and high salinity. 展开更多
关键词 mixed surfactant system Temperature resistance Salt tolerance Carbonate reservoir Enhanced oil recovery
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A mixed stochastic user equilibrium model considering influence of advanced traveller information systems in degradable transport network 被引量:4
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作者 程琳 楼小明 +1 位作者 周静 马捷 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1182-1194,共13页
Advanced traveler information systems (ATIS) can not only improve drivers' accessibility to the more accurate route travel time information, but also can improve drivers' adaptability to the stochastic network cap... Advanced traveler information systems (ATIS) can not only improve drivers' accessibility to the more accurate route travel time information, but also can improve drivers' adaptability to the stochastic network capacity degradations. In this paper, a mixed stochastic user equilibrium model was proposed to describe the interactive route choice behaviors between ATIS equipped and unequipped drivers on a degradable transport network. In the proposed model the information accessibility of equipped drivers was reflected by lower degree of uncertainty in their stochastic equilibrium flow distributions, and their behavioral adaptability was captured by multiple equilibrium behaviors over the stochastic network state set. The mixed equilibrium model was formulated as a fixed point problem defined in the mixed route flows, and its solution was achieved by executing an iterative algorithm. Numerical experiments were provided to verify the properties of the mixed network equilibrium model and the efficiency of the iterative algorithm. 展开更多
关键词 mixed stochastic user equilibrium model degradable transport network advanced traveler information systems (ATIS) drivers' behavioral adaptability multiple equilibrium behaviors fixed point problem
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A Feature Weighted Mixed Naive Bayes Model for Monitoring Anomalies in the Fan System of a Thermal Power Plant 被引量:3
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作者 Min Wang Li Sheng +1 位作者 Donghua Zhou Maoyin Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第4期719-727,共9页
With the increasing intelligence and integration,a great number of two-valued variables(generally stored in the form of 0 or 1)often exist in large-scale industrial processes.However,these variables cannot be effectiv... With the increasing intelligence and integration,a great number of two-valued variables(generally stored in the form of 0 or 1)often exist in large-scale industrial processes.However,these variables cannot be effectively handled by traditional monitoring methods such as linear discriminant analysis(LDA),principal component analysis(PCA)and partial least square(PLS)analysis.Recently,a mixed hidden naive Bayesian model(MHNBM)is developed for the first time to utilize both two-valued and continuous variables for abnormality monitoring.Although the MHNBM is effective,it still has some shortcomings that need to be improved.For the MHNBM,the variables with greater correlation to other variables have greater weights,which can not guarantee greater weights are assigned to the more discriminating variables.In addition,the conditional P(x j|x j′,y=k)probability must be computed based on historical data.When the training data is scarce,the conditional probability between continuous variables tends to be uniformly distributed,which affects the performance of MHNBM.Here a novel feature weighted mixed naive Bayes model(FWMNBM)is developed to overcome the above shortcomings.For the FWMNBM,the variables that are more correlated to the class have greater weights,which makes the more discriminating variables contribute more to the model.At the same time,FWMNBM does not have to calculate the conditional probability between variables,thus it is less restricted by the number of training data samples.Compared with the MHNBM,the FWMNBM has better performance,and its effectiveness is validated through numerical cases of a simulation example and a practical case of the Zhoushan thermal power plant(ZTPP),China. 展开更多
关键词 Abnormality monitoring continuous variables feature weighted mixed naive Bayes model(FWMNBM) two-valued variables thermal power plant
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A PRIORI L_2 ERROR ESTIMATES FOR A NONLINEAR PARABOLIC SYSTEM BASED ON COMBINING THE METHOD OF CHARACTERISTICS WITH MIXED FINITE ELEMENT PROCEDURE 被引量:2
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作者 袁益让 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1993年第1期11-24,共14页
A nonlinear parabolic system is derived to describe incompressible nuclear waste-disposal contamination in porous media. A sequential implicit tirne-stepping is defined, in which the pressure and Darcy velocity of the... A nonlinear parabolic system is derived to describe incompressible nuclear waste-disposal contamination in porous media. A sequential implicit tirne-stepping is defined, in which the pressure and Darcy velocity of the mixture are approximated simultaneously by a mixed finite element method and the brine, radionuclid and heat are treated by a combination of a Galerkin finite element method and the method of characteristics. Optimal-order convergence in L2 is proved. Time-truncation errors of standard procedures are reduced by time stepping along the characteristics of the hyperbolic part of the brine, radionuclide and heal equalios, temporal and spatial error are lossened by direct compulation of the velocity in the mixed method, as opposed to differentiation of the pressure. 展开更多
关键词 Nonlinear PARABOLIC system mixed FINITE element characlerisitics L2 estimates.
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An Experimental Study on Alkaline/Surfactant/Polymer Flooding Systems Using Natural Mixed Carboxylate 被引量:2
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作者 牟建海 李干佐 李英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期162-166,共5页
Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding sy... Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively. 展开更多
关键词 alkaline/surfactant/polymer flooding system natural mixed carboxylate interfacial tension phase behavior orthogonal-test-design
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