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Earthquake Science 2018年第3期31卷 154-165页

作者： Chunyang Ji Vincent lee Sonny Astani Department of Civil and Environmental Engineering University of Southern California

A closed-form wave equation analytic solution of two-dimensional scattering and diffraction of outof-plane（SH） waves by an almost semi-circular shallow cylindrical hill on a flat, elastic and homogeneous half space is proposed by applying the discrete Fourier series expansions of sine and cosine functions. The semi-circular hill problem is discussed as a special case for the new formulated *** with the previous semi-circular cases solutions, the present method can give surface displacement amplitudes which agrees well with previous results. Although the proposed equation can only solve the problem of SH-waves diffracted by almost semi-circular shallow hills, the stress and displacement residual amplitudes are numerical insignificantly everywhere. Moreover, the influences of the depth-towidth ratio（a parameter defined in this paper to evaluate the shallowness of the topography of hills） on ground motions are presented and summarized. The limitations and errors of truncation from Graf’s addition theorem and Fourier series equations in the present paper are also discussed.

关键词： closed-form analytic solution SH waves surface motions shallow circular cylindrical hill

Mid-infrared superabsorbers based on quasi-periodic moiré metasurfaces

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Chinese Optics Letters 2018年第5期16卷 12-16页

作者： Yaoran Liu Zilong Wu Eric H. hill Yuebing Zheng Department of Mechanical Engineering and Texas Materials Institute The University of Texas at Austin Austin Texas 78712 USA

We report on mid-infrared superabsorbers based on quasi-periodic moiré metasurfaces in metal-insulator-metal form. By varying the spacer thickness, moiré rotation angle, and filling factor of the superabsorbers, we can tune narrowband or broadband absorption in a systematic way. With their high tunability of near-unity absorption and simple fabrication, in combination with decoupled mode theory for an efficient design, moiré superabsorbers are well-suited for a wide range of applications in sensing, imaging, and communication.

关键词： Mid-infrared superabsorbers based on quasi-periodic moir metasurfaces

A hybrid swarm population of Pinus densiflora × P. sylvestris inferred from sequence analysis of chloroplast DNA and morphological characters

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Journal of Forestry Research 2013年第1期24卷 53-60页

作者： Young Hee Joung Jerry L. hill Jung Oh Hyun Ding Mu Juchun Luo Do Hyung lee Takayuki Kawahara Jeung Keun Suh Mark S. Roh Chonnam National University School of Biological Sciences & TechnologyGwangjuKorea US Department of Agriculture Forest ServiceDorena Genetic Resource CenterWashington State UniversityPullmanWA99164USA Seoul National University College of Agriculture and Life SciencesSeoulKorea Chinese Academy of Agricultural Science Beijing Forestry University College of Resources and Environment Yeungnam University College of Natural ResourcesDepartment of Forest ResourcesGyeongsanKorea Hokkaido Research Center Forestry and Forest Products Research InstituteSapporoJapan. Dankook University School of Bio-Resource ScienceDepartment of Environment HorticultureCheonanKorea. US Department of Agriculture Agricultural Research ServiceUS National ArboretumFloral and Nursery Plants Research UnitBeltsvilleMD 20705USA.

To confirm a hybrid swarm population of Pinus densiflora × P. sylvestris in Jilin, China, we used needles and seeds from P. densiflora, P. sylvestris, and P. densiflora × P. sylvestris collected from natural stands or experimental stations to study whether shoot apex morphology of 4-year old seedlings can be correlated with the sequence of a chloroplast DNA simple sequence repeat marker （cpDNA SSRs）. Total genomic DNA was extracted and subjected to sequence analysis of the pine cpDNA SSR marker Pt15169. Results show that morphological characters from 4-year old seedlings did not correlate with sequence variants of this marker. Marker haplotypes from all P. sylvestris trees had a CTAT element that was absent from all sampled P. densiflora trees. However, both haplotype classes involving this insertion/deletion element were found in a P. densiflora × P. sylvestris population and its seedling progeny. It was concluded that the P. densiflora × P. sylvestris accessions sampled from Jilin, China resulted from bi-directional crosses, as evidenced by both species’ cpDNA haplotypes within the hybrid swarm population.

关键词： P. sylvestris var. sylvestriformis chloroplast DNA simplesequence repeat sequencing hybrid swarm population

Optimal coordinated voltage control of power systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第2期7卷 257-262页

作者：李艳君 hill David J 吴铁军 Institute of Intelligent Systems and Decision Making Zhejiang University Hangzhou 310027 China Department of Electronic Engineering City University of Hong Kong Hong Kong China

An immune algorithm solution is proposed in this paper to deal with the problem of optimal coordination of local physically based controllers in order to preserve or retain mid and long term voltage stability. This problem is in fact a global coordination control problem which involves not only sequencing and timing different control devices but also tuning the parameters of controllers. A multi-stage coordinated control scheme is presented, aiming at retaining good voltage levels with minimal control efforts and costs after severe disturbances in power systems. A self-pattem-recognized vaccination procedure is developed to transfer effective heuristic information into the new generation of solution candidates to speed up the convergence of the search procedure to global optima. An example of four bus power system case study is investigated to show the effectiveness and efficiency of the proposed algorithm, compared with several existing approaches such as differential dynamic programming and tree-search.

关键词： Power systems Voltage control Immune algorithm Global optimization

Diffraction of anti-plane SH waves by a semi-circular cylindrical hill with an inside concentric semi-circular tunnel

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Earthquake Engineering and Engineering Vibration 2004年第2期3卷 249-262页

作者： Vincent W.lee 罗昊梁建文 Dept.of Civil and Environmental Engineering Univ.of Southern CaliforniaLos AngelesCA 90089-2531USA Professor Civil Engineering and Architecture Experiment Center Dept.of Civil EngineeringShanghai Jiaotong Univ.800 Dongchuan Rd.Shanghai 200240China Dept.of Civil EngineeringTianjin Univ.Tianjin 300072China Assistant Engineer Dept.of Civil Engineering Tianjin Univ.Tianjin 300072China Professor

A closed-form analytic solution of two-dimensional scattering and diffraction of plane SH waves by a semi- cylindrical hill with a semi-cylindrical concentric tunnel inside an elastic half-space is presented using the cylindrical wave functions expansion *** solution is reduced to solving a set of infinite linear algebraic *** expansion theorem with the form of complex exponential function and cosine function is *** solutions are obtained by truncation of the infinite *** accuracy of the presented numerical results is carefully verified.

关键词： SH waves hill tunnels close-form analytic solution amplifications

Scattering of plane P waves by a semi-cylindrical hill: analytical solution

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Earthquake Engineering and Engineering Vibration 2005年第1期4卷 27-36页

作者：梁建文张彦帅 Vincent W lee Department of Civil Engineering Tianjin University Tianjin 300072 ChinaProfessor Department of Civil Engineering Tianjin University Tianjin 300072 ChinaGraduateStudent Department of Civil Engineering University of Southern California Los AngelesCA 90089-2531USAProfessor

An analytical solution for scattering of plane P waves by a semi-cylindrical hill was derived by using the wave function expansion method, and convergence of the solution and accuracy of truncation were verified. The effect of incident frequency and incident angle on the surface motion of the hill was discussed, and it was shown that a hill greatly amplifies incident plane P waves, and maximum horizontal displacement amplitudes appear mostly at the inclined incidence of waves, which are located at the half-space; and maximum vertical displacement amplitudes emerge mostly at the vertical incidence of waves, which are situated at the hill.

关键词： hill plane P waves scattering analytical solution amplification

Equations of Propagation of Uncertainty on the ITS-90 in the Sub-ranges from 13.8033 K to 933.473 K

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Chinese Physics Letters 2005年第3期22卷 558-560页

作者：康志茹傅广生 K.D.hill CollegeofPhysicsTechnology HebeiUniversityBaoding071002//HebeiProvincialInstituteofMetrologyShijiazhuang050051 CollegeofPhysicsTechnology HebeiUniversityBaoding071002 NationalResearchCouncilofCanada OttawaCanada

Based on implicit differentiation, we present the total differential of linear interpolation and the equation of propagation of uncertainty on the ITS-90 in any of the sub-ranges from 13.8033K to 933.473K. It is proven that the sensitivity coefficients of the linear interpolation are still linear combinations of the basis functions comprising the interpolation equation, only with different constants that can be presented in the determinant form. This solves the question to express the equation of propagation of uncertainty of a complex interpolation comprised of many different basic functions.

关键词： TS-90 Sub-ranges 13.8033K 933.473K

Surface motion of a semi-cylindrical hill for incident plane SV waves: Analytical solution

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Acta Seismologica Sinica(English Edition) 2006年第3期19卷 251-263页

作者：梁建文张彦帅 Vincent W lee Tianjin University Tianjin 300072 China University of Southern California Los Angeles CA 90089-2531 USA

An analytical solution for surface motion of a semi-cylindrical hill for incident plane SV waves was derived by using the wave function expansion method and the auxiliary function technique, and convergence of the solution and accuracy of truncation were verified. The effect of incident frequency and angle as well as hill width on the surface motion of the hill was discussed by numerical examples. It was shown that, a hill greatly amplifies incident plane SV waves, and the maximal amplification may reach 4 times of that for free-field response; and for incident waves of low frequency, the maximal displacement amplitudes emerge mostly at the half-space, however, for incident waves of high frequency, the maximal displacement amplitudes appear mostly at the hill.

关键词： hill plane SV waves scattering surface motion analytical solution

The importance of epithelial-mesenchymal transition and autophagy in cancer drug resistance

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Cancer Drug Resistance 2020年第1期3卷 38-47页

作者： Charlotte hill Yihua Wang School of Biological Sciences Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUK Institute for Life Sciences University of SouthamptonSouthampton SO171BJUK

Epithelial-mesenchymal transition(EMT)and autophagy are both known to play important roles in the development of ***,these processes are now being utilised as targets for *** is globally one of the leading causes of death,and,despite many advances in treatment options,patients still face many *** resistance in cancer-therapy is a large problem,and both EMT and autophagy have been shown to ***,given the context-dependent role of these processes and the complexity of the interactions between them,elucidating how they both act alone and interact is *** this review,we provide insight into the current landscape of the interactions of autophagy and EMT in the context of malignancy,and how this ultimately may affect drug resistance in cancer therapy.

关键词： Epithelial-mesenchymal transition autophagy cancer drug resistance metastasis therapy

Selenoprotein P: Recent Studies in Rats and in Humans

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Biomedical and Environmental Sciences 1997年第2期10卷 198-208页

作者： KRISTINAE·hill RAYMONDF·BURK DivisionofGastroenterology DepartmentofMedicineandClinicalNutritionResearchUnit DivisionofGastroenter

Purification of selenoprotein P from rat plasma has allowed detailed characterization of the protein from that species. Chromatographic studies have revealed the existence of at least two isoforms of the *** isoform is a truncated protein with termination of protein synthesis occurring at the second selenocysteine codon. Immunohistochernical studies have shown that the rat protein is associated with capillary endothelial cells in the liver, kidney,and brain. In vivo experiments were designed to study the relationship between selenoprotein P and lipid peroxidation. F2 isoprostanes were measured to quantitate the extent of lipid peroxidation caused by diquat. Using selenium-deficient rats supplemented with seleniurn, it was demonstrated that selenoprotein P appearance correlated with disappearance of diquat-induced lipid peroxidation. This finding is consistent with the protein serving to protect the plasma membrane from oxidative damage. Development of a radioimmunoassay to measure selenoprotein P has allowed assessment of the protein in humans. Measurements of the protein in selenium-deficient Chinese subjects indicated that it can be used as an index of selenium nutritional status in humans

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