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Rapid accuracy determining DNA purity and concentration in heavy oils by spectrophotometry methods
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作者 YunYang Wan HongMei Mu +4 位作者 Na Luo JianPing Yang Yan Tian Ning Hong HaiLiang Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3394-3399,共6页
DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstr... DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstream molecular biology research. In this study, three different spectrophotometry methods, BPM, NDTT and NPMTTZ were compared for their performance in determining DNA concentration and purity in 32 oil samples, and molecule methods like quantitative real-time PCR (qPCR) and high-throughput sequence were also performed to help assess the accuracy of the three methods in determining DNA concentration and purity. For ordinary heavy oil (OHO), extra heavy oil (EHO) and super heavy oil (SHO), the characteristics of high viscosity (η), density (ρ) and resin plus asphaltene content will affect the DNA extraction and UV determination. The DNA concentration was decreased as density increased: OHO (11.46 ± 18.34 ng/μL), EHO (6.68 ± 9.67 ng/μL) and SHO (6.20 ± 7.83 ng/μL), and the DNA purity was on the reverse: OHO (1.31 ± 0.27), EHO (1.54 ± 0.20), and SHO (1.83 ± 0.32). The results suggest that spectrophotometry such as BPM and NPMTTZ are qualitatively favorite methods as the quick non-consumable methods in determining DNA concentration and purity of medium oil and heavy oil. 展开更多
关键词 Heavy oil DNA concentration DNA purity SPECTROPHOTOMETRY qPCR
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Research on the Follow-Up Control Strategy of Biaxial Fatigue Test of Wind Turbine Blade Based on Electromagnetic Excitation
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作者 Wenzhe Guo Leian Zhang +2 位作者 Chao Lv Weisheng Liu Jiabin Tian 《Energy Engineering》 EI 2023年第10期2307-2323,共17页
Aiming at the drift problem that the tracking control of the actual load relative to the target load during the electromagnetic excitation biaxial fatigue test of wind turbine blades is easy to drift,a biaxial fatigue... Aiming at the drift problem that the tracking control of the actual load relative to the target load during the electromagnetic excitation biaxial fatigue test of wind turbine blades is easy to drift,a biaxial fatigue testingmachine for electromagnetic excitation is designed,and the following strategy of the actual load and the target load is studied.A Fast Transversal Recursive Least Squares algorithm based on fuzzy logic(Fuzzy FTRLS)is proposed to develop a fatigue loading following dynamic strategy,which adjusts the forgetting factor in the algorithmthrough fuzzy logic to overcome the contradiction between convergence accuracy and convergence speed and solve the phenomenon of amplitude overshoot and phase lag of the actual load relative to the target load.Combined with the previous research results,a simulation model was constructed to verify the strategy’s effectiveness.Field tests were carried out to verify its follow-up effect.The results showthat the tracking error of flapwise and edgewise direction iswithin 4%,which has better robustness and dynamic and static performance than the traditional Recursive Least Squares(RLS)algorithm. 展开更多
关键词 Wind turbine blades biaxial fatigue loading tracking control fuzzy FTRLS
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Dynamic Response Analysis of Semi-Submersible Floating Wind Turbine with Different Wave Conditions
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作者 Mingzhen Jiang Guanghui Qiao +4 位作者 Jiwen Chen Xuemei Huang Leian Zhang Yongshuang Wen Yuhuan Zhang 《Energy Engineering》 EI 2023年第11期2531-2545,共15页
To address the problem of poor wave resistance of existing offshore floating wind turbines,a new type of semisubmersible platform with truncated-cone-type upper pontoons is proposed by combining the characteristics of... To address the problem of poor wave resistance of existing offshore floating wind turbines,a new type of semisubmersible platform with truncated-cone-type upper pontoons is proposed by combining the characteristics of offshore wind turbine semi-submersible floating platforms.Based on the coupled hydrodynamic,aerodynamic,and mooring force physical fields of FAST,the surge,heave,pitch,and yaw motions responses of the floating wind turbine under different wave heights and periods are obtained,and the mooring line tension responses are also obtained;and compare the dynamic response of the new semi-submersible platform with the OC4-DeepCwind platformat six degrees of freedom.The results show that different wave conditions have obvious effects on the heave and pitch motions of the new floating wind turbine,and fewer effects on the surge and yaw motions;the tensegrity response of the mooring system is more affected by the wave conditions;compared with the OC4-DeepCwind floating wind turbine,the pitch and roll response of the new floating wind turbine has been significantly reduced and has good stability. 展开更多
关键词 Floating wind turbine semi-submersible platform wave loading different wave conditions dynamic response
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Review of grain ref inement methods for as-cast microstructure of magnesium alloy 被引量:6
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作者 Song Changjiang Han Qingyou Zhai Qijie 《China Foundry》 SCIE CAS 2009年第2期93-103,共11页
As the lightest structural metal,Mg and Mg-based alloys have great potential applications in the aerospace,automotive and nuclear industries.However,such applications have been limited by low ductility and strength.Th... As the lightest structural metal,Mg and Mg-based alloys have great potential applications in the aerospace,automotive and nuclear industries.However,such applications have been limited by low ductility and strength.Theoretically,small grain sized structure can synchronously improve its ductility and strength.Yet,universally reliable grain ref inement techniques for the magnesium alloys are still under investigation and some are in strong debating.This paper presents a brief review of development of grain ref inement methods for magnesium alloys,which would contribute to a better understanding of the factors controlling grain ref inement and provide an outlook of future research in this fi eld. 展开更多
关键词 晶粒细化 细化方法 镁合金 铸态组织 审查 航空航天 颗粒大小 控制因素
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Effect of Gamma Irradiation on Total Phenolic Content and <i>in Vitro</i>Antioxidant Activity of Pomegranate (<i>Punica granatum</i>L.) Peels 被引量:3
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作者 Amol B. Mali Kalpana Khedkar Smita S. Lele 《Food and Nutrition Sciences》 2011年第5期428-433,共6页
Pomegranate peels were studied for the effect of gamma irradiation on microbial decontamination along with its effect on total phenolic content and in vitro antioxidant activity. Gamma irradiation was applied at vario... Pomegranate peels were studied for the effect of gamma irradiation on microbial decontamination along with its effect on total phenolic content and in vitro antioxidant activity. Gamma irradiation was applied at various dose levels (5.0, 10.0, 15.0 and 25.0 kGy) on pomegranate peel powder. Both the values of total phenolic content and in vitro antioxi- dant activity were positively correlated and showed a significant increase (p < 0.05) for 10.0 kGy irradiated dose level immediately after irradiation and 60 days of post irradiation storage. At 5.0 kGy and above dose level, gamma irradia- tion has reduced microbial count of pomegranate peel powder to nil. Post irradiation storage studies also showed that, the irradiated peel powder was microbiologically safe even after 90 days of storage period. 展开更多
关键词 POMEGRANATE Peels Food Irradiation Total PHENOLIC Content In VITRO Antioxidant Activity Microbial Load
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Towards full demonstration of high areal loading sulfur cathode in lithium–sulfur batteries 被引量:15
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作者 Long Kong Qi Jin +5 位作者 Xi-Tian Zhang Bo-Quan Li Jin-Xiu Chen Wan-Cheng Zhu Jia-Qi Huang Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第12期17-22,共6页
Lithium–sulfur(Li–S)batteries have been recognized as promising substitutes for current energy-storage technologies owing to their exceptional advantages in very high-energy density and excellent material sustainabi... Lithium–sulfur(Li–S)batteries have been recognized as promising substitutes for current energy-storage technologies owing to their exceptional advantages in very high-energy density and excellent material sustainability.The cathode with high sulfur areal loading is vital for the practical applications of Li–S batteries with very high energy density.However,the high sulfur loading in an electrode results in poor rate and cycling performances of batteries in most cases.Herein,we used diameters of 5.0(D5)and 13.0(D13)mm to probe the effect of electrodes with different sizes on the rate and cycling performances under a high sulfur loading(4.5 mg cm^-2).The cell with D5 sulfur cathode exhibits better rate and cycling performances comparing with a large(D13)cathode.Both the high concentration of lithium polysulfides and corrosion of lithium metal anode impede rapid kinetics of sulfur redox reactions,which results in inferior battery performance of the Li–S cell with large diameter cathode.This work highlights the importance of rational matching of the large sulfur cathode with a high areal sulfur loading,carbon modified separators,organic electrolyte,and Li metal anode in a pouch cell,wherein the sulfur redox kinetics and lithium metal protection should be carefully considered under the flooded lithium polysulfide conditions in a working Li–S battery. 展开更多
关键词 Lithium sulfur batteries High areal sulfur loading Lithium anode protection Sulfur redox reactions Polysulfide interm ediates
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Application of Wavelet Transform in the Prediction of Navel Orange Vitamin C Content by Near-Infrared Spectroscopy 被引量:4
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作者 XIA Jun-fang LI Xiao-yu +2 位作者 LI Pei-wu MA Qian DING Xiao-xia 《Agricultural Sciences in China》 CAS CSCD 2007年第9期1067-1073,共7页
This study was to search for an approach for rapid measurement of orange vitamin C (Vc) content. By using different decomposing levels of Daubechies 3 wavelet transform, the near-infrared spectra signals obtained fr... This study was to search for an approach for rapid measurement of orange vitamin C (Vc) content. By using different decomposing levels of Daubechies 3 wavelet transform, the near-infrared spectra signals obtained from intact fruits of 100 navel orange samples were denoised, and the results of the predicted Vc contents for the corresponding samples determined by the reconstructed spectra after denoising were validated by means of PLS-CV (partial least squared-cross validation). It was shown that the prediction effects verified by PLS-CV analysis varied when different wavelet transform decomposing levels were employed. At the wavelet decomposing level 4, the best prediction effect was obtained, with the correlation coefficient R between the prediction and true values being 0.9574 and the expected variance RMSECV being as low as 3.9 mg 100 g^-1. Furthermore, the 11 different approaches for the pretreatment of the near-infrared spectrum were compared. It was found that the calibration model established by PLS using spectra pretreated by wavelet transform denoising provided the best prediction for Vc content, exhibiting the highest correlation between the prediction and true values by cross validation. In conclusion, the near infrared spectral model denoised by means of wavelet transform can be used for accurate, rapid, and nondestructive quantitative analysis on navel orange Vc content. 展开更多
关键词 navel orange near infrared spectroscopy wavelet denoising partial least square
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AMS Measurement of ^(36)Cl with a Q3D Magnetic Spectrometer at CIAE 被引量:1
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作者 李朝历 何明 +6 位作者 张伟 武绍勇 李振宇 何贤文 刘建成 董克君 姜山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期543-547,共5页
The ratio of 36Cl/Cl can determine the exposure age of surface rocks and monitor the secular equilibrium of 36Cl of sedimentary and igneous rock in groundwater. Due to the uncertainty effects of different chemical sep... The ratio of 36Cl/Cl can determine the exposure age of surface rocks and monitor the secular equilibrium of 36Cl of sedimentary and igneous rock in groundwater. Due to the uncertainty effects of different chemical separation processes for removing 36S, there is a high degree of uncertainty in 36Cl accelerator mass spectrometry (AMS) measurements if the ratio of 36Cl/Cl is lower than 10-14. A 36Cl1 AMS higher sensitivity measurement has been set up by using a AE-Q3D method at the China Institute of Atomic Energy (CIAE). The performances of AE-Q3D method for 36Cl-AMS measurement had been systemically studied. The experimental results show that the AE-Q3D method has a higher isobar suppression factor. Taking advantage of direct removing 36S, the sample preparation can be simplified and the uncertainty effects of different chemical separation processes can be reduced in 36Cl AMS measurements. 展开更多
关键词 36Cl AMS AE-Q3D isobar separation
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Petrological and Os Isotopic Characteristics of Zedong Peridotites in the Eastern Yarlung–Zangbo Suture in Tibet 被引量:2
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作者 LAI Shengmin YANG Jingsui +3 位作者 Yildirim DILEK XIONG Fahui JIANG Rui CHEN Yanhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第2期442-461,共20页
The Zedong ophiolites in the eastern Yarlung-Zangbo suture zone of Tibet represent a mantle slice of more than 45 km2. This massif consists mainly of mantle peridotites, with lesser gabbros, diabases and volcanic rock... The Zedong ophiolites in the eastern Yarlung-Zangbo suture zone of Tibet represent a mantle slice of more than 45 km2. This massif consists mainly of mantle peridotites, with lesser gabbros, diabases and volcanic rocks. The mantle peridotites are mostly harzburgite, lherzolite; a few dike-like bodies of dunite are also present. Mineral structures show that the peridotites experienced plastic deformation and partial melting. Olivine (Fos9.7-91.2), orthopyroxene (Enss-92), clinopyroxene (En4-49Wo47-slFS2-4) and spinel [Mg^#=lOOxMg/(Mg+Fe)]=49.1-70.7; Cr^#=(100xCr/(Cr+Al)=18.8-76.5] are the major minerals. The degree of partial melting of mantle peridotites is 10%-40%, indicating that the Zedong mantle peridotites may experience a multi-stage process. The peridotites are characterized by depleted major element compositions and low REE content (0.08-0.62 ppm). Their "spoon-shaped" primitivemantle normalized REE patterns with (La/Sm)N being 0.50-6.00 indicate that the Zedong ultramafic rocks belong to depleted residual mantle rocks. The PGE content of Zedong peridotites (18.19-50.74 ppb) is similar with primary mantle with Pd/Ir being 0.54-0.60 and Pt/Pd being 1.09-1.66. The Zedong peridotites have variable, unradiogenic Os isotopic compositions with 187Os/18Os=0.1228 to 0.1282. A corollary to this interpretation is that the convecting upper mantle is heterogeneous in Os isotopes. All data of the Zedong peridotites suggest that they formed originally at a mid-ocean ridge (MOR) and were later modified in supra-subduction zone (SSZ) environment. 展开更多
关键词 Os isotopes Zedong peridotites Yarlung-Zangbo suture zone mid-ocean ridge (MOR) supra-subduction zone (SSZ)
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Effect of Extrusion Process Parameters and Particle Size of Sorghum Flour on Expanded Snacks Prepared Using Different Varieties of Sorghum (Sorghum bicolour L.) 被引量:1
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作者 Manisha V. Jadhav Uday S. Annapure 《Journal of Agricultural Science and Technology(B)》 2013年第2期71-85,共15页
关键词 工艺参数 高粱 品种 粒子大小 零食 面粉 挤压 双色
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Comparative Analysis of Produced Water Collected from Different Oil Gathering Centers in Kuwait 被引量:1
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作者 Khaled AlAnezi Meshal Al-Samhan +4 位作者 Mohamed Belkharchouche Waleed Abuhaimed Sabah Alali Khalaf Alenizi Abdulqader Alfuraij 《Journal of Environmental Protection》 2018年第6期736-750,共15页
Kuwait is one of the major oil-producing countries, with an estimated oil production of around three million barrels/day. Increased oil production has resulted in the production of large amounts of produced water, whi... Kuwait is one of the major oil-producing countries, with an estimated oil production of around three million barrels/day. Increased oil production has resulted in the production of large amounts of produced water, which is a major problem for Kuwait Oil Company. Kuwait Oil Company generates large amounts of produced water daily and thus deserves special attention. A study of the characteristics of the produced water will determine how it can be treated and later used for irrigation or disposed without harming the environment. In this paper, samples of produced water from different oilfields in Kuwait were collected, and physiochemical analyses were carried out. The salt content, TDS and other physical characteristics of the Kuwait produced water samples were compared with those of other produced water samples from different oil-producing countries. 展开更多
关键词 PRODUCED WATER Characterization OIL Production ENVIRONMENT and WATER Management
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The origin of sulfuryl-containing components in SEI from sulfate additives for stable cycling of ultrathin lithium metal anodes 被引量:6
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作者 Jin-Xiu Chen Xue-Qiang Zhang +8 位作者 Bo-Quan Li Xin-Meng Wang Peng Shi Wancheng Zhu Aibing Chen Zhehui Jin Rong Xiang Jia-Qi Huang Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第8期128-131,I0005,共5页
In the light of wireless and non-fossil society based on portable electronics, electric vehicles, and smart grids, secondary batteries with higher energy density, faster charge, and safer operation are pursued persist... In the light of wireless and non-fossil society based on portable electronics, electric vehicles, and smart grids, secondary batteries with higher energy density, faster charge, and safer operation are pursued persistently [1]. Nowadays, commercial lithium(Li)-ion batteries have been practically applied in our daily life. However,the energy density of Li-ion batteries based on intercalation chemistry is approaching to the theoretical value due to the limited specific capacity of graphite anode(372 mA h g-1) [2]. 展开更多
关键词 Ultrathin lithium anodes DENDRITES Electrolyte additives Solid electrolyte interphase Lithium batteries
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Solution of Combined Heat and Power Economic Dispatch Problem Using Direct Optimization Algorithm 被引量:1
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作者 Dedacus N. Ohaegbuchi Olaniyi S. Maliki +1 位作者 Chinedu P. A. Okwaraoka Hillary Erondu Okwudiri 《Energy and Power Engineering》 CAS 2022年第12期737-746,共10页
This paper presents the solution to the combined heat and power economic dispatch problem using a direct solution algorithm for constrained optimization problems. With the potential of Combined Heat and Power (CHP) pr... This paper presents the solution to the combined heat and power economic dispatch problem using a direct solution algorithm for constrained optimization problems. With the potential of Combined Heat and Power (CHP) production to increase the efficiency of power and heat generation simultaneously having been researched and established, the increasing penetration of CHP systems, and determination of economic dispatch of power and heat assumes higher relevance. The Combined Heat and Power Economic Dispatch (CHPED) problem is a demanding optimization problem as both constraints and objective functions can be non-linear and non-convex. This paper presents an explicit formula developed for computing the system-wide incremental costs corresponding with optimal dispatch. The circumvention of the use of iterative search schemes for this crucial step is the innovation inherent in the proposed dispatch procedure. The feasible operating region of the CHP unit three is taken into account in the proposed CHPED problem model, whereas the optimal dispatch of power/heat outputs of CHP unit is determined using the direct Lagrange multiplier solution algorithm. The proposed algorithm is applied to a test system with four units and results are provided. 展开更多
关键词 Economic Dispatch Lagrange Multiplier Algorithm Combined Heat and Power Constraints and Objective Functions Optimal Dispatch
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From statistical analysis to process optimization during cladding using a Nd:YAG laser 被引量:2
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作者 亚伟 Pathiraj B. 于兴华 《China Welding》 CAS 2022年第4期7-22,共16页
Application of statistical methods to optimize the process parameters was achieved by employing full factorial design of experiments,which was accomplished by cladding using stepwise ramped laser power.The correlation... Application of statistical methods to optimize the process parameters was achieved by employing full factorial design of experiments,which was accomplished by cladding using stepwise ramped laser power.The correlations between clad geometry and dilution(clad characteristics)and the main process parameters laser power(P_(l)),cladding speed(v_(c)),the powder feed rate(m)were obtained through application of variance analysis technique(ANOVA).The obtained correlations between the main processing parameters and the clad characteristics are discussed and a statistical model was developed.The desirability investigations using the developed statistical model were performed by considering the clad geometry,aspect ratio,dilution and hardness.Optimal parameters for cladding Stellite 6 on AISI 420 steel substrate and for cladding Nucalloy 488V on S355 J2 steel substrate were obtained.The optimal processing parameters can be applied to clad other materials with similar chemical compositions. 展开更多
关键词 laser cladding statistical model process optimization clad geometry DILUTION powder efficiency
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Optimal Path Planning for a Remote Sensing Unmanned Ground Vehicle in a Hazardous Indoor Environment 被引量:1
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作者 Mohammad R. Alenezi Abdullah M. Almeshal 《Intelligent Control and Automation》 2018年第4期147-157,共11页
Urban search and rescue robots are playing an increasingly important role during disasters and with their ability to search within hazardous and dangerous environments to assist the first respond teams. Surveying and ... Urban search and rescue robots are playing an increasingly important role during disasters and with their ability to search within hazardous and dangerous environments to assist the first respond teams. Surveying and remote sensing the hazardous areas are two of the urgent needs of the rescue team to identify the risks before the intervention of the emergency teams. With such time-critical missions, the path planning and autonomous navigation of the robot is one of the primary concerns due to the need of fast and feasible path that is comprehensive enough to assess the associated risks. This paper presents a path planning method for navigating an unmanned ground vehicle within in an indoor hazardous area with minimum priori information. The algorithm can be generalized to any given map and is based on probabilistic roadmap path planning method with spiral dynamics optimization algorithm to obtain the optimal navigating path. Simulations of the algorithm are presented in this paper, and the results promising results are illustrated using Matlab and Simulink simulation environments. 展开更多
关键词 REMOTE Sensing PATH PLANNING UGV AUTONOMOUS Mobile ROBOT
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Load Disturbance Conditions for Current Error Feedback and Past Error Feedforward State-Feedback Iterative Learning Control 被引量:1
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作者 Athari Alotaibi Asmaa Alkandri Muhammad Alsubaie 《Intelligent Control and Automation》 2021年第2期65-72,共8页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Iterative learning control is a controlling tool developed to overcome periodic disturbances acting on repetitive sy... <div style="text-align:justify;"> <span style="font-family:Verdana;">Iterative learning control is a controlling tool developed to overcome periodic disturbances acting on repetitive systems. State-feedback ILC controller was designed based on the use of the small gain theorem. Stability conditions were reported in the case of past error and current error feedback schemes based on Singular values. Disturbances acting on the load of the system w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">reported for the case of past error feedforward only which kept the investigation of the current error feedback as an open question. This paper develops </span><span style="font-family:Verdana;">a comparison between the past error feedforward and current error feedback schemes disturbance conditions in singular values. As a result, the conditions found highly support the use of the past error over the current error feedback.</span> </div> 展开更多
关键词 Iterative Learning Control Disturbance Conditions Singular Values
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Factors aff ecting lipid and fatty acid composition of Calanus sinicus in the Yellow Sea and the East China Sea in spring 被引量:1
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作者 Yanqing WANG Zhencheng TAO +1 位作者 Chaolun LI Mengtan LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期173-182,共10页
The factors aff ecting lipid and fatty acid composition of copepod Calanus sinicus in the Yellow Sea(YS)and the East China Sea(ECS)were examined in this study.In spring,there were signifi cant diff erences between the... The factors aff ecting lipid and fatty acid composition of copepod Calanus sinicus in the Yellow Sea(YS)and the East China Sea(ECS)were examined in this study.In spring,there were signifi cant diff erences between these two regions for both environmental conditions and food availability.Such regional diff erence signifi cantly infl uenced the lipid and fatty acid profi les of C.sinicus.Our results show that C.sinicus has a higher lipids content in ECS,especially for wax ester and triglyceride lipids,indicating a more active and effi cient predation.According to BIO-ENV analysis,the variation of lipids profi les may be infl uenced majorly by water temperature.Moreover,the fatty acids(FAs)profi les of C.sinicus were also diff erent between YS and ECS,especially in the four major contributors,C22꞉1ω11,eicosapentaenoic acid(EPA),docosahexenoic acid(DHA),and C20꞉1ω9.The considerable amounts of self-biosynthesized FAs of herbivorous copepod(C22꞉1ω11 and C20꞉1ω9)and low DHA/EPA ratio may indicate that C.sinicus in ECS feed mainly on phytoplankton comparing to those in YS.The fatty acid profi les of C.sinicus were aff ected by the diff erences in food availability. 展开更多
关键词 Calanus sinicus lipid storage wax ester fatty acid composition Yellow Sea and East China Sea
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Anew Design of Reticule for Seeker
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作者 Abdulrazak Abdulsalam Mohammed 《材料科学与工程(中英文B版)》 2011年第6期802-810,共9页
关键词 设计方法 手提袋 求职 调制传递函数 光学系统 分形函数 调制器 导引头
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Propulsion Performance of Spanwise Flexible Wing Using Unsteady Panel Method
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作者 NAJAFI Saeed LIU Pengfei 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第3期505-518,共14页
In this paper, the propulsion performance of a spanwise flexible oscillating wing, which is broadly similar to the undulation of a fin fluke, is investigated. The geometry of the fluke underwent three prescribed harmo... In this paper, the propulsion performance of a spanwise flexible oscillating wing, which is broadly similar to the undulation of a fin fluke, is investigated. The geometry of the fluke underwent three prescribed harmonic oscillating motions simultaneously while surging with constant velocity. The effect of deflection phase angle, flexibility parameter, and wing tip deflection amplitude on thrust coefficient and swimming efficiency was studied. A low-order unsteady panel method coupled with a time stepping algorithm for free wake alignment is implemented in a computer program to estimate the propulsion efficiency of lifting bodies. A novel approach is introduced to evaluate the singular integrals of line vortices by using an adaptive mollifier function. This method is an efficient way to accelerate computational speed by reducing the order of problem from R^3 to body boundaries. Results present the significant effect of phase angle on the propulsion characteristics of oscillating fluke. 展开更多
关键词 propulsion performance fin whale fluke flexible wing panel method wake alignment
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Interpretation of Dark Matter and Quark-Gluon Plasma: The Generation of the Periodic Table Elements and Its Phase Diagram: A Novel Millennium Power Plant
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作者 Murad Al Shibli 《Natural Science》 2015年第9期438-458,共21页
This paper presents a novel physical interpretation of the state of matter of the quark-gluon as the most fundamental building blocks in nature. Such a model is derived based on the assumption that dark matter and dar... This paper presents a novel physical interpretation of the state of matter of the quark-gluon as the most fundamental building blocks in nature. Such a model is derived based on the assumption that dark matter and dark energy behave as a perfect ideal fluid at extremely high temperature. By the virtue of Boltzmann constant of the ideal gas law and NASA’s Cosmic Microwave Background Explorer (CMB) which estimate that the space has an average temperature close to 2.7251 Kelvin, then the equivalent mass-energy of the fundamental particle of the dark matter/dark energy is determined. Moreover, assuming a uniform space dark energy/dark matter density, then the critical temperature at which the dark matter has a unity entity per volume is identified as 64 × 1012 K. The calculated critical temperature of the quark-gluon plasma is found to be proportional to the temperature generated by colliding heavy ions at the Relativistic Heavy Ion Collider (RHIC) and European Organization for Nuclear Research (CERN). Moreover, the individual critical temperatures of the quark-gluon plasma matter at which the elements of the Periodic Table are generated are explicitly determined. The generation temperature trend of the elements of the Periodic Table groups and Periods is then demonstrated. Accordingly, the phase diagram of the quark-gluon state matter is proposed. Finally, a new model of quark-gluon power generation plant is proposed and aims to serve humanity with new energy sources in the new millennium. 展开更多
关键词 DARK MATTER DARK Energy QUARK-GLUON Plasma Equation of State Periodic TABLE Standard Model
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