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A joint optimization framework for wheat harvesting and transportation considering fragmental farmlands

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Information Processing in Agriculture 2021年第1期8卷 1-14页

作者： P.He j.li Faculty of Engineering Nanjing Agricultural UniversityNanjing 210031PR China

Crop harvesting and transportation should be considered as an integrated system to be optimized aiming to reduce the total operational ***,current studies mainly focused on how to reduce operational cost for a link,not from integrated *** this paper,a joint problem which consists of harvesting and transportation problem is implemented and optimized to meet the better schedule with less operational *** harvesting and transportation problems could respectively be considered as a vehicle routing problem with multiple trips and a transportation problem,.These two problems should be optimized jointly because combine-harvesters and transporters should be synchronized at fragmental farmlands.A mixed integer programming is employed considering all constraints arising in the joint optimized ***,a hybrid algorithm is presented to find an optimum solution for this *** different cases are used to verify the performance of the hybrid ***,our real cases are used to prove that there is a significant improvement if the integrated wheat harvesting and transportation policy is *** results indicate that the model and algorithm is an effective approach to help farmers to decrease reaping costs.

关键词： Wheat Harvesting and transportation Vehicle routing Mixed integer programming

Motion of the moonlet in the binary system 243 Ida

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Acta Mechanica Sinica 2018年第1期34卷 214-224页

作者： L.Lan Y.Ni Y.jiang j.li School of Aerospace Engineering Tsinghua University State Key Laboratory of Astronautic Dynamic Xi'an Satellite Control Center

The motion of the moonlet Dactyl in the binary system 243 Ida is investigated in this paper. First, periodic orbits in the vicinity of the primary are calculated, including the orbits around the equilibrium points and large-scale orbits. The Floquet multipliers’ topological cases of periodic orbits are calculated to study the orbits’ stabilities. During the continuation of the retrograde near-circular orbits near the equatorial plane, two period-doubling bifurcations and one Neimark–Sacker bifurcation occur one by one, leading to two stable regions and two unstable regions. Bifurcations occur at the boundaries of these regions. Periodic orbits in the stable regions are all stable, but in the unstable regions are all unstable. Moreover, many quasi-periodic orbits exist near the equatorial plane. Long-term integration indicates that a particle in a quasi-periodic orbit runs in a space like a tire. Quasi-periodic orbits in different regions have different styles of motion indicated by the Poincare sections. There is the possibility that moonlet Dactyl is in a quasi-periodic orbit near the stable region I, which is enlightening for the stability of the binary system.

关键词： Binary system Bifurcation Periodic orbits Quasi-periodic orbits

Surface-effect on detection ability of fluorescent Eu(btc)metal-organic frameworks to metal ions

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journal of Rare Earths 2021年第4期39卷 446-452页

作者： jiaolong Peng Wei Zhou Heping Ding Huanhuan Du Shujing j.li Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business UniversityBeijing 100048China Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China

Eu(btc)metal organic frameworks(MOFs)were prepared by co-precipitation method via 1,2,4-benzenetricarboxylic acids(H3btc)connecting with Eu^(3+)ions,and the morphology was controlled from compact spherical to irregular honeycomb by adjusting the pH of reaction *** luminescence properties of Eu(btc)MOFs are found to be related to the surface morphology of products,and the compact spherical one performs stronger emission *** sensing ability of Eu(btc)MOFs to 11 kinds of metal ions was investigated and a prominent quenching effect occurrs in Fe^(3+),or Ni^(2+)*** on UV—vis absorption analysis,an“ion-fence”model presents the competition to absorb exciting light between Eu(btc)MOFs and adsorbed metal *** on Stern-Volmer equation,the Eu(btc)detection is found with higher Ksv value and a lower detection ***,a higher sensing efficiency is confirmed in the Eu(btc)MOFs with loose honeycomb due to aggravating porous surface offering much more sites for metal ions.

关键词： MOF Surface-effect Detection Metal ions Rare earths

Statistical moment-based structural damage detection method in time domain

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 13-23页

作者： j.Zhang Y.L.Xu j.li Y.Xia j.C.li Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Department of Building Engineering Tongji University Faculty of Engineering University of Technology Sydney

A novel structural damage detection method with a new damage index,i.e.,the statistical moment-based damage detection（SMBDD） method in the frequency domain,has been recently *** aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary *** applicability and effectiveness of the SMBDD method in the time domainis verified both numerically and *** buildings with various damage scenarios are first numerically investigated in the time domain taking into account the effect of measurement *** applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimentally investigated through a series of shaking table tests,in which two three-story shear building models with four damage scenarios *** identified damage locations and severities are then compared with the preset *** comparative results are found to be satisfactory,and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.

关键词： damage detection statistical moment time domain non-Gaussian non-stationary experimental investigation

INVESTIGATION OF INFLUENCE OF HYDROGEN ATTACK ONFATIGUE PROPERTIES OF PRESSURE VESSEL STEELS

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 141-149页

作者： j.L.li K.F.Wang j.li Z.M.Yao W.Ke Fushun Petroleum Inst Fushun China

Influence of hydrogen attack on mechanical and fatigue properties of 1020, 15CrMo and 2.25Cr-1Mo steels has been studied, which were exposed to gaseous hydrogen at pressure of 18MPa and 300-480℃ for up to 480h. The results of fatigue test showed that hydrogen attack (HA) resulted in an obvious change in fatigue properties of 1020 and 15CrMo steels, however, 2.25Cr-1Mo steel showed a lower susceptibility to hydrogen attack due to the addition of Cr and Mo. Fatigue crack behaviour for 1020 steel is attributed to hydrogen attack damage and the crack closure induced by the rough cracking surface, which lead to a valley on △Kth～HA% plot. The change in the fatigue behaviour of 15CrMo steel is possibly caused by severe surface decarburization.

关键词： hydrogen attack pressure vessel steel threshold △K value crack closure

Top 10 research achievements of traditional Chinese medicine in 2023

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Science of Traditional Chinese Medicine

Science of Traditional Chinese Medicine 2024年第4期2卷 255-259页

作者： China Association of Chinese Medicine j.li China Association of Chinese Medicine BeijingChina Chinese Association of Chinese Medicine No.4Yinghua East StreetChaoyang DistrictBeijing 100029China

In order to fulfill the requirements of the 20th National Congress of the Communist Party of China and the Opinions on Promoting the Inheritance,Innovation and Development of Traditional Chinese Medicine,regularly summarize the research achievements of traditional Chinese medicine(TCM),present the academic progress of TCMdynamically,and give full play to the leadership of academic groups in research,the China Association of ChineseMedicine organized the selection of the top 10 academic achievements of TCMin *** selection work adhered to the“4 orientations”;eliminated the“4 only”;highlighted the solution of clinical problems and scientific questions,the development of the industry,and the exploratory,forward-looking,innovative,and breakthrough research;and focused on new laws,new discoveries,new methods,new products,and new theories in the basic research and applied basic research of *** dynamic collection,preliminary examination,review,and final judgment,the top 10 academic achievements of TCMin 2023 were ***,breakthroughs have been achieved in the treatment of ST-segment elevation myocardial infarction by ***,evidence has been gained regarding the efficacy of acupuncture in treating chronic spontaneous urticaria and vomiting in ***,evidence has been gained regarding the improvement of neurological function outcomes by Xuesaitong soft capsules in treating patients with ischemic ***,the mechanisms of Huashi Baidu Powder and Pien Tze Huang in clinical treatment have been ***,the pharmacodynamic mechanisms of astragaloside and capsaicin have been revealed for the first ***,new technologies represented by spatial metabolomics assist in elucidating the material basis of the complex systems ***,network medicine framework reveals the genericmechanism underlying the effectiveness of TCM treatment based on syndrome ***,a comprehensive platform for multidimensional nucle

关键词： Traditional Chinese medicine(TCM) Research achievements Acute myocardial infarction Spontaneous urticaria Vomiting of pregnancy Acupuncture Intestinal flora Spatial metabolomics

Magnetic and Transport Properties of Mn_(0.98)Cr_(0.02)Te Epitaxial Films Grown on Al_2O_3 Substrates

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journal of Materials Science & Technology 2014年第2期30卷 103-106页

作者： Z.H.Wang D.Y.Geng j.li Y.B.li Z.D.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Centre for Materials PhysicsChinese Academy of Sciences Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences

The epitaxial Mno0.98Cr0.02Te films on single crystal Al2O3 （0001） substrates were prepared by pulsed laser deposition. The X-ray diffraction and scanning electron microscopy results showed that the good continuous epitaxial film was obtained with substrate temperature of 500 ℃. When the substrate temperature reached 700 ℃, the film was island growth and the manganese oxides phase appeared. The temperature dependence of both the magnetization and electrical resistance showed a sharp rise at around 60 K due to the magnetoelastic coupling. The temperature dependence of the electrical resistance of Mno0.98Cr0.02Te provided evidence for a transition from the metallic to semiconducting state at 305 K due to the spin disorder scattering with a large contribution from the influence of magnon drag.

关键词： Magnetic properties Mno0.98Cr0.02Te films X-ray diffraction Epitaxial film

On the microstructural origin of premature failure of creep strength enhanced martensitic steels

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journal of Materials Science & Technology 2021年第28期87卷 269-279页

作者： j.li C.Xu G.Zheng W.j.Dai C.C.Bu G.Chen MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing210094China Nanjing jiuzhu New Materials Institute Co. Ltd.Nanjing211151China Condensed Materials Laboratory Co. Ltd.Yangzhou225200China Yangzhou Chengde Steel Pipe Co. Ltd.Yangzhou225200China

The creep strength enhanced martensitic steels are key material for the main power generating units in ultra-supercritical *** on the evaluation of their creep rupture life show there is an overestimation of rupture life after long-term creep,which is known as premature ***,the microstructural origin of the premature failure remains *** in this study,we have carefully investigated the microstructural transformations and their influences on creep rupture behavior,showing that the evolution of martensite and M_(23)C_(6) carbides as well as Laves phase are responsible for the premature *** using multi-step TTP-LMP method,we confirmed a three-stage creep rupture behavior under different stress *** quantitative analysis showed that the coarsening of M_(23)C_(6) carbides and recovery of martensite exert equal and dominant effects on the premature failure in the medium stress region,while precipitation and coarsening of Laves phase are responsible for the premature failure in the low stress region.

关键词： Creep strength enhanced martensitic steel Premature failure M_(23)C_(6)carbides Martensite recovery Laves phase

Application Prospect of Fission-Powered Spacecraft in Solar System Exploration Missions

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Space(Science & Technology) 2021年第1期2021卷 309-323页

作者： Y.Xia j.li R.Zhai j.Wang B.lin Q.Zhou Beijing Institute of Spacecraft Environment Engineering BeijingChina Science and Technology on Reliability and Environmental Engineering Laboratory BeijingChina Institute of Nuclear and New Energy Technology of Tsinghua University The Key Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationBeijingChina

Fission power is a promising technology,and it has been proposed for several future space *** is being considered for highpower missions whose goal is to explore the solar system and even *** fission power has made great progress when NASA’s 1 kWe Kilowatt Reactor Using Stirling TechnologY(KRUSTY)prototype completed a full power scale nuclear test in *** success stimulated a new round of research competition among the major space *** article reviews the development of the Kilopower reactor and the KRUSTY system *** summarizes the current missions that fission reactors are being considered as a power and/or propulsion *** projects include visiting jupiter and Saturn systems,Chiron,and Kuiper belt object;Neptune exploration missions;and lunar and Mars surface base *** studies suggest that the Fission Electric Propulsion(FEP)/Fission Power System(FPS)is better than the Radioisotope Electric Propulsion(REP)/Radioisotope Power System(RPS)in the aspect of cost for missions with a power level that reaches~1 kWe,and when the power levels reaches~8 kWe,it has the advantage of lower *** a mission that travels further than~Saturn,REP with plutonium may not be cost acceptable,leaving FEP the only *** missions prefer the use of FPS because it satisfies the power level of 10’s kWe,and FPS vastly widens the choice of possible landing *** to the current situation,we are expecting a flagship-level fission-powered space exploration mission in the next 1-2 decades.

关键词： satis Saturn isotope