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STUDY ON RECIPROCATING SEALS FOR A LARGER DIAMETER AXIAL PISTON 被引量:2
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作者 YangJian YangHuayong XuBing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期152-155,共4页
Sealing performance of the reciprocating seals on a larger diameter (100 mmin diameter) axial piston is theoretically investigated. Based on the characteristics of theclearance flow between the seal and the piston, re... Sealing performance of the reciprocating seals on a larger diameter (100 mmin diameter) axial piston is theoretically investigated. Based on the characteristics of theclearance flow between the seal and the piston, reasonable boundary conditions for Navier-Stokesequations are determined and the equations are modified, so that the final equations can describethe real flow state of the clearance flow. Through combining the final equations with finite elementmethod, the pressure distributions within the clearance field during the reciprocating motion ofthe piston and the leakage rate with the pressure are studied. The deflections of the seal whichaffect sealing performance are calculated as well. Sealing performance of piston seals using oil asthe working liquid is compared with using water. It is concluded that the seal using water as theworking liquid is under dry friction, which cannot be dealt with the theory of fluid mechanics. Theseal structure is only acceptable using oil as the working liquid.. 展开更多
关键词 larger diameter axial piston Reciprocating seals Sealing performance
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Larger Foraminiferal Biostratigraphy and Facies Analysis of the Oligocene–Miocene Asmari Formation in the Western Fars Sub-basin, Zagros Mountains, Iran 被引量:1
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作者 Tahereh HABIBI Telm BOVER-ARNAL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第6期2079-2097,共19页
The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under ... The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under tropical conditions, is explored in terms of larger foraminiferal biostratigraphy, facies analysis and sequence stratigraphy in a new section at Papoon cropping out in the western Fars sub-basin, in the south-east of the Zagros belt. Facies analysis shows evidence of re-working and transport of skeletal components throughout the depositional system, interpreted here as a carbonate ramp. The foraminifera-based biozones identified include the Globigerina–Turborotalia cerroazulensis–Hantkenina Zone and Nummulites vascus–Nummulites fichteli Zone, both of Rupelian age, the Archaias asmaricus–Archaias hensoni–Miogypsinoides complanatus Zone of Chattian age and the ‘Indeterminate’ Zone of Aquitanian age. The vertical sedimentary evolution of the formation exhibits a progressive shallowing of the facies belts and thus the succession is interpreted as a high-rank low-order regressive systems tract. This long-lasting Rupelian–Aquitanian regressive event is in accordance with accepted global long-term eustatic curves. Accordingly, long-term eustatic trends would have been a factor controlling accommodation during the deposition of the Asmari Formation studied in the western Fars sub-basin. 展开更多
关键词 larger foraminifera BIOSTRATIGRAPHY sequence stratigraphy carbonate platform OLIGOCENE Zagros Basin Iran
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Sun-Moon-Earth Interactions with Larger Earthquakes Worldwide Connections 被引量:2
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作者 Marilia Hagen Anibal Azevedo 《Open Journal of Earthquake Research》 2019年第4期267-298,共32页
The aim of this paper is to investigate the effects on Moon-Earth gravitational variations and Moon phases during three Solar Cycless (SC22, SC23, SC24). The first part defines gravitational forces as a force that cre... The aim of this paper is to investigate the effects on Moon-Earth gravitational variations and Moon phases during three Solar Cycless (SC22, SC23, SC24). The first part defines gravitational forces as a force that creates an oscillation when the moon is reaching the Perigee, the smallest distance between the Moon and Earth during its rotational movement around Earth. It has a small amplitude and large period. Unlikely other authors, we do not find a direct connection between the Moon phases and big earthquakes worldwide. The study is performed through the three Solar Cycless, which refers to the variation in the Sun’s magnetic field. However, a strong indication appeared that almost the totality of the largest quakes studied happened preferentially at the subduction zones, in the Southern Hemisphere. In this research we apply experimental data to find the tide force, and the Perigee position is an experimental value. Other parameters are experimental, such as the length of Solar Cycless, the Moon’s phases connected to each earthquake where M ≥ 7.5. The calculations use regression in time to find the results. Our model considers in the regression the period 1986-2018. 展开更多
关键词 Solar Cycless Moon-Earth GRAVITATIONAL Forces larger EARTHQUAKES
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A systematic review of robot-assisted partial nephrectomy outcomes for advanced indications:Large tumors(cT2-T3),solitary kidney,completely endophytic,hilar,recurrent,and multiple renal tumors
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作者 Savio Domenico Pandolfo Clara Cerrato +11 位作者 Zhenjie Wu Antonio Franco Francesco Del Giudice Alessandro Sciarra Paolo Verze Giuseppe Lucarelli Ciro Imbimbo Sisto Perdonà Edward E.Cherullo Francesco Porpiglia Ithaar H.Derweesh Riccardo Autorino 《Asian Journal of Urology》 CSCD 2023年第4期390-406,共17页
Objective:Robot-assisted partial nephrectomy(RAPN)has become widely used for treatment of renal cell carcinoma and it is expanding in the field of complex renal masses.The aim of this systematic review was to analyze ... Objective:Robot-assisted partial nephrectomy(RAPN)has become widely used for treatment of renal cell carcinoma and it is expanding in the field of complex renal masses.The aim of this systematic review was to analyze outcomes of RAPN for completely endophytic renal masses,large tumors(cT2-T3),renal cell carcinoma in solitary kidney,recurrent tumors,completely endophytic and hilar masses,and simultaneous and multiple tumors.Methods:A comprehensive search in the PubMed,Scopus,Web of Science,and Cochrane Central Register of Controlled Trials databases was performed in December 2022 for English language papers.The primary endpoint was to evaluate the role of RAPN in the setting of each category of complex renal masses considered.The secondary endpoint was to evaluate the surgical and functional outcomes.Results:After screening 1250 records,43 full-text manuscripts were selected,comprising over 8500 patients.Twelve and thirteen studies reported data for endophytic and hilar renal masses,respectively.Five and three studies reported outcomes for cT2-T3 and solitary kidney patients,respectively.Four studies focused on redo-RAPN for recurrent tumors.Two studies investigated simultaneous bilateral renal masses and five reports focused on multiple tumor excision in ipsilateral kidney.Conclusion:Over the past decade,evidence supporting the use of RAPN for the most challenging nephron-sparing surgery indications has continuously grown.Although limitations remain including study design and lack of detailed long-term functional and oncological outcomes,the adoption of RAPN for the included advanced indications is associated with favorable surgical outcomes with good preservation of renal function without compromising the oncological result.Certainly,a higher likelihood of complication might be expected when facing extremely challenging cases.However,none of these indications should be considered per se an exclusion criterion for performing RAPN.Ultimately,a risk-adapted approach should be employed. 展开更多
关键词 Robot-assisted partial nephrectomy Complex renal mass Solitary kidney larger tumors(cT2-T3) Endophytic and hilar mass Recurrent tumor Simultaneous and multiple tumor
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论利用影响力受贿罪的客观方面 被引量:5
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作者 李冠煜 《福建警察学院学报》 2010年第1期87-94,共8页
利用影响力受贿罪是《刑法修正案(七)》增设的犯罪,与我国《刑法》规定的受贿罪有本质区别,与《联合国反腐败公约》中的影响力交易罪存在处罚范围上的差异。利用影响力受贿罪的客观方面包括利用影响力、通过职务行为为请托人谋取不正当... 利用影响力受贿罪是《刑法修正案(七)》增设的犯罪,与我国《刑法》规定的受贿罪有本质区别,与《联合国反腐败公约》中的影响力交易罪存在处罚范围上的差异。利用影响力受贿罪的客观方面包括利用影响力、通过职务行为为请托人谋取不正当利益、索取或者收受财物和数额较大或者有其他较重情节几个构成要素,除了索取或者收受财物这一要素外,其他的要素自有其特殊性。 展开更多
关键词 利用影响力受贿罪 职务行为 谋取不正当利益 数额较大 较重情节
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不同芜萍饵料组分对两种社群规模的螯虾生长影响(英文) 被引量:1
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作者 季鹏飞 严幸云 +1 位作者 黄成 唐建清 《Agricultural Science & Technology》 CAS 2012年第7期1583-1586,共4页
[目的]研究不同比例的芜萍饵料组分对2种社群规模下螯虾生长的影响。[方法]试验设置了芜萍与商品饲料6种比例的混合饵料(0、20%、40%、60%、80%、100%)分别饲喂最小社群与较大社群下的克氏原螯虾幼体,以研究不同芜萍组分下螯虾的生长状... [目的]研究不同比例的芜萍饵料组分对2种社群规模下螯虾生长的影响。[方法]试验设置了芜萍与商品饲料6种比例的混合饵料(0、20%、40%、60%、80%、100%)分别饲喂最小社群与较大社群下的克氏原螯虾幼体,以研究不同芜萍组分下螯虾的生长状况,并对相同芜萍组分下最小社群和较大社群螯虾的生长差异。[结果]2种社群规模的不同芜萍组分螯虾生长结果为:体长最大的均为60%芜萍组,最小的均为纯芜萍组;整齐性最好的均为20%芜萍组;无论是最小社群还是较大社群,各自不同芜萍组分的存活率差异均不显著。相同芜萍组分下2个社群间的同期比较结果为:最小社群的平均体长显著大于较大社群,而存活率前者也大于后者,但差异并未达到显著水平。[结论]综合生长、存活及整齐等指标,认为芜萍与商品饲料合适的混合比例为40%~60%;社群规模较大对鳌虾生长有显著抑制作用,因此应在克氏原螯虾苗种培养环境中设置隔离障碍。 展开更多
关键词 Key WORDS Wolffia MINIMAL COMMUNITY larger COMMUNITY Mixed feed Optimum PROPORTION
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软土地区旧桩拔除技术和新建桩基础调整方案及施工措施 被引量:6
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作者 刘文渊 吴君 《水利与建筑工程学报》 2020年第1期141-145,共5页
结合天津南开区某地块定向经济适用房项目,介绍其在基础施工中遇到旧预制方桩时,采用全套管高压喷气、射水振动沉管施工工艺清孔拔桩,并对该工艺进行分析得出:该拔桩施工工艺适用于软土地区旧桩拔除项目;并针对旧桩孔无法回填压实、部... 结合天津南开区某地块定向经济适用房项目,介绍其在基础施工中遇到旧预制方桩时,采用全套管高压喷气、射水振动沉管施工工艺清孔拔桩,并对该工艺进行分析得出:该拔桩施工工艺适用于软土地区旧桩拔除项目;并针对旧桩孔无法回填压实、部分新建桩基础与拔除旧桩孔距离较近等原因导致钻孔倾斜、串孔等问题,提出远离旧桩位置或调整至旧桩桩心位置等方法调整桩位,并采用加大桩径、增设承台等调整方案承担因调整桩位而产生的上部偏心荷载;采用拌和白灰、分层压实、回填静置等措施提高回填土的密实度,采用保证垂直度和调节泥浆配合比等措施,以改善不良施工条件,得出适当增加混凝土充盈系数保证成桩质量等施工经验,为后续类似工程提供借鉴。 展开更多
关键词 清孔拔桩 调整桩位 加大桩径 回填土密实度 防止串孔 增加混凝土量
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关于跳汰机“大排矸”操作标准 被引量:1
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作者 付学军 《选煤技术》 CAS 北大核心 2005年第4期38-40,共3页
介绍并分析了跳汰机“大排矸”操作的两种常用标准,提出了以二段入料>1.80g/cm3密度级含量作为“大排矸”操作标准的建议。
关键词 大排矸 矸石灰分 一段矸石排出率 分选密度
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Metal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction 被引量:5
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作者 Ziming Zhao Yu Long +3 位作者 Sha Luo Yutong Luo Ming Chen Jiantai Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期546-555,共10页
As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR el... As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR electrocatalysts is far from enough and a systematic research is needed to gain a better improvement. This article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a simple and feasible method, and used as a metal-free catalyst for electrocatalytic NRR. Experiment result and density functional theory(DFT) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(HER) at the same time. In addition, the larger specific surface area also makes more active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. The electrocatalyst shows an excellent catalytic activity for NRR in 0.1 M HCl, including Faradaic efficiency of 10.96%, NH_(3) yields of 17.85 lg h^(-1) mg_(cat)^(-1)., and good stability(over 20 h). 展开更多
关键词 2D C_(3)N_(4)-NV larger specific surface area Nitrogen vacancy Electrocatalyst NRR
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刍议行政处罚听证制度较大数额之确定 被引量:2
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作者 林清兴 《黑龙江省政法管理干部学院学报》 2014年第1期36-38,共3页
行政处罚法首次规定了听证制度,对于提高行政效率,促进依法行政,保障行政相对人的合法权益起到了重要的作用,也搭建了一个行政机关与行政相对人进行对话交流的平台。法律规定行政机关拟作出较大数额行政处罚决定时,当事人有听证的权利... 行政处罚法首次规定了听证制度,对于提高行政效率,促进依法行政,保障行政相对人的合法权益起到了重要的作用,也搭建了一个行政机关与行政相对人进行对话交流的平台。法律规定行政机关拟作出较大数额行政处罚决定时,当事人有听证的权利。但较大数额是一个不确定法律概念。从行政处罚听证制度的意义着手,剖析现行"较大数额"纷繁复杂规定的乱象,从确定主体、方式和基础出发以期完善现行较大数额的合理确定机制,达致法律统一、和谐。 展开更多
关键词 行政处罚 听证 较大数额 确定
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Electron-Electron Collision Term Describing the Reflections Induced Scattering in a Magnetized Plasma
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作者 董超 李定 姜畅 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期56-60,共5页
For an electron-electron collision with characteristic scale length larger than the relative gyro-radius of the two colliding electrons, when the initial relative parallel kinetic energy cannot surmount the Coulomb re... For an electron-electron collision with characteristic scale length larger than the relative gyro-radius of the two colliding electrons, when the initial relative parallel kinetic energy cannot surmount the Coulomb repulsive potential, reflection will occur with interchange of the parallel velocities of the two electrons after the collision. The Fokker–Planck approach is employed to derive the electron collision term C_R describing parallel velocity scattering due to the reflections for a magnetized plasma where the average electron gyro-radius is much smaller than the Debye length but much larger than the Landau length. The electron parallel velocity friction and diffusion coefficients due to the reflections are evaluated, which are found not to depend on the electron perpendicular velocity. By studying the temporal evolution of the H quantity due to CR, it is found that C_R eventually makes the system relax to a state in which the electron parallel velocity distribution is decoupled from the perpendicular velocity distribution. 展开更多
关键词 For an electron-electron scale LENGTH larger VELOCITY distribution
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Novel transit-time oscillator(TTO) combining advantages of radial-line and axial TTO
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作者 徐伟力 贺军涛 +4 位作者 令钧溥 宋莉莉 邓秉方 戴欧志雄 葛行军 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期220-224,共5页
A novel transit-time oscillator(TTO)is proposed in this paper.An axial cathode which has been widely used in high power microwave(HPM)source and an extractor with radial feature are adopted.In this way,the inherent ad... A novel transit-time oscillator(TTO)is proposed in this paper.An axial cathode which has been widely used in high power microwave(HPM)source and an extractor with radial feature are adopted.In this way,the inherent advantages of axial and radial TTO,both of which can be utilized as high-quality intense relativistic electron beam(IREB),can be generated and the power capacity is also increased.The working mode isπ/2 mode of TM01 based on small-signal theory,and under the same energy storage,the maximum electric field in extractor decreases 16.3%.Besides,by utilizing the natural bending of the solenoid,this TTO saves over 60%of the length required by the uniform magnetic field,and consequently reduces the energy consumed by solenoid.The PIC simulation shows that by using 1.0-T decreasing magnetic field generated by the shorter solenoid,3.37-GW microwave at 12.43 GHz is generated with 620-kV and 13.27-kA input,and the overall conversion efficiency is 41%. 展开更多
关键词 AXIAL TTO radial-feature EXTRACTOR larger power capacity shorter UNIFORM magnetic field
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Sequence and Biostratigraphy of Lower Cenozoic Succession in the Kopet-Dagh Basin, NE of Iran
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作者 Batool Rivandi Mohammad Vahidinia +2 位作者 Mehdi Nadjafi Assadolah Mahboubi Abbas Sadeghi 《Open Journal of Geology》 2013年第3期240-249,共10页
The main purpose of this paper is the sequence stratigraphy and biostratigraphy of lower Tertiary sediments on the base of larger benthic foraminifera in northeast of Iran (Chehel-Kaman Formation). This formation main... The main purpose of this paper is the sequence stratigraphy and biostratigraphy of lower Tertiary sediments on the base of larger benthic foraminifera in northeast of Iran (Chehel-Kaman Formation). This formation mainly consists of Limestone, dolomite and interbeds of sand, shale and evaporate sediments. Petrographical studies indicate that these sediments may have been deposited on a shallow carbonate platform ramp and consist of 4 carbonate lithofacies (15 subfacies). These lithofacies may have been deposited in open marine, shoal, lagoon and tidal flat environmental conditions. Sequence stratigraphy analysis led to identification of 4 third-order depositional sequences, bounded by type 2 (within the top of the underlying Pestehleigh Formation) and type 1 sequence boundaries (paleosol). Interpreted sea level curve in this basin can be relatively correlated with global curves during Paleocene time and a with a sea-level fall occurred in the latest Paleocene, followed by a rise in the earliest Eocene. Biostratigraphy study led to the identification of 32 larger benthic Foraminifera genera. The Paleocene/Eocene boundary has been probably recorded as a thin red paleosol horizon (~10 - 15 cm). 展开更多
关键词 Kopeh-Dagh BASIN PALEOGENE larger BENTHIC FORAMINIFER SEQUENCE Stratigraphy
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A Corpus-based Analysis of the Usage of Naked Eye
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作者 虞晶 《海外英语》 2010年第12X期281-281,共1页
It is widely accepted that eye is a high-frequency word in English,and one of the stronger collocations is naked eye.In order to research the usage of naked eye,a concordance line of naked eye is selected from corpus ... It is widely accepted that eye is a high-frequency word in English,and one of the stronger collocations is naked eye.In order to research the usage of naked eye,a concordance line of naked eye is selected from corpus evidence.The collocation,meaning,attitude words and larger variable expression of naked eye are mainly examined with the purpose of better studying the usage of naked eye. 展开更多
关键词 CORPUS naked eye COLLOCATION MEANING attitude WORDS larger variable expression
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On the occurrence of Neoplanorbulinella Matsumaru, 1976(Foraminifera) from the late Oligocene of Central Iran(Qom Formation):Palaeobiogeographic implications
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作者 Mehdi Sarfi Mohsen Yazdi-Moghadam 《Journal of Palaeogeography》 SCIE CSCD 2024年第1期80-91,共12页
The shallow marine carbonates of the upper Oligocene Qom Formation yielded several occurrences of the foraminiferan genus Neoplanorbulinella Matsumaru. Neoplanorbulinella saipanensis Matsumaru has so far been recorded... The shallow marine carbonates of the upper Oligocene Qom Formation yielded several occurrences of the foraminiferan genus Neoplanorbulinella Matsumaru. Neoplanorbulinella saipanensis Matsumaru has so far been recorded from the late Eocene-early Miocene of Japan and late Oligocene of NE Italy whereas N. malatyaensis Gedik is only reported from the Oligocene from its type locality in the Malatya Basin, eastern Turkey. The new records reported here from the Qom Formation indicate that both species occur in the Dobaradar section, ca. 10 km south of the city of Qom in North-Central Iran. The palaeogeographic distribution of these two species therefore has to be extended as far as the palaeolongitude of current Central Iran.The accompanying larger benthic foraminifers, including Miogypsinoides complanatus(Schlumberger),M. formosensis Yabe and Hanzawa, Spiroclypeus margaritatus(Schlumberger), Operculina complanata(Defrance), and Risananeiza pustulosa Boukhary et al., indicate the upper Chattian SBZ 23 Zone. The coexistence of the N. saipanensis and N. malatyaensis points to suitable palaeobiogeographic conditions of Central Iran to host Western and Eastern Tethyan taxa. 展开更多
关键词 larger foraminifers Planorbulinids BIOSTRATIGRAPHY Qom Formation Central Iran
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Quest towards “factoring larger integers with commercial D-Wave quantum annealing machines” 被引量:3
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作者 XinMei Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第6期130-130,共1页
Integer factorization (IFP), also called prime factorization, is an important problem in number theory, cryptography, and quantum computation. Factoring large integers to attack the RSA cryptosystem is intractable for... Integer factorization (IFP), also called prime factorization, is an important problem in number theory, cryptography, and quantum computation. Factoring large integers to attack the RSA cryptosystem is intractable for powerful supercomputers, let alone classical computers. In 1994, Shor [1]presented an algorithm that potentially enabled a quantum computer to find prime factors in polynomial time. 展开更多
关键词 QUEST towards FACTORING larger INTEGERS with COMMERCIAL D-WAVE quantum ANNEALING machines
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SE Asian Cenozoic Larger Foraminifera:Taxonomic Questions,Apparent Radiation and Abrupt Extinctions 被引量:2
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作者 Peter Lunt Xiwu Luan 《Journal of Earth Science》 SCIE CAS CSCD 2022年第6期1378-1399,共22页
The Cenozoic larger foraminifera are important for biostratigraphy in SE Asia.This review examines the taxonomic inconsistencies of this group and especially the confusion over concepts of evolution,migration,radiatio... The Cenozoic larger foraminifera are important for biostratigraphy in SE Asia.This review examines the taxonomic inconsistencies of this group and especially the confusion over concepts of evolution,migration,radiation and extinction.It is proposed that from the Mediterranean to Indo-Pacific,Latest Eocene through Miocene,larger foraminifera populations were more homogenous than previously believed.Lineages show a slow morphological radiation interrupted by several extinctions.This pattern is superimposed on a long-term decline in larger foraminiferal abundance.The dating of the major biostratigraphic events are qualified.The main lineages of larger foraminifera can be classified by their evolutionary style.The classically“large”genera have highly peramorphic trends achieved through strong orthoselection,and these lineages were the most severely hit by a series of Mid-Eocene to Mid-Miocene extinction events.Other carbonate facies taxa that are traditionally grouped with the larger foraminifera are characterised by weak paramorphism,and these were much less affected by the extinction events.Some of these weakly peramorphic forms underwent Latest Miocene to recent radiation to and locally become rock-forming organisms.The three major and one minor larger foraminiferal extinction events since the Mid Eocene coincide with abrupt tectonic events across SE Asia.However,there are probably multiple causes for these extinctions,including global climatic changes. 展开更多
关键词 larger foraminifera evolution BIOSTRATIGRAPHY EXTINCTION
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An LQP-Based Symmetric Alternating Direction Method of Multipliers with Larger Step Sizes 被引量:3
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作者 Zhong-Ming Wu Min Li 《Journal of the Operations Research Society of China》 EI CSCD 2019年第2期365-383,共19页
Symmetric alternating directionmethod of multipliers(ADMM)is an efficient method for solving a class of separable convex optimization problems.This method updates the Lagrange multiplier twice with appropriate step si... Symmetric alternating directionmethod of multipliers(ADMM)is an efficient method for solving a class of separable convex optimization problems.This method updates the Lagrange multiplier twice with appropriate step sizes at each iteration.However,such step sizes were conservatively shrunk to guarantee the convergence in recent studies.In this paper,we are devoted to seeking larger step sizes whenever possible.The logarithmic-quadratic proximal(LQP)terms are applied to regularize the symmetric ADMM subproblems,allowing the constrained subproblems to then be converted to easier unconstrained ones.Theoretically,we prove the global convergence of such LQP-based symmetric ADMM by specifying a larger step size domain.Moreover,the numerical results on a traffic equilibrium problem are reported to demonstrate the advantage of the method with larger step sizes. 展开更多
关键词 Convex optimization Symmetric alternating direction method of multipliers Logarithmic-quadratic proximal regularization larger step sizes Global convergence
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Evolution,Extinction,Homology and Homoplasy of the Larger Benthic Foraminifera from the Carboniferous to the Present Day,as Exemplified by Planispiral-Fusiform and Discoidal Forms 被引量:1
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作者 Marcelle K.BouDagher-Fadel 《Journal of Earth Science》 SCIE CAS CSCD 2022年第6期1348-1361,共14页
Examples of evolution,extinction and homoplasy of the larger benthic foraminifera(LBF)occur throughout their history.Since the Carboniferous,LBF have thrived in carbonate-rich tropical and subtropical shallow-marine s... Examples of evolution,extinction and homoplasy of the larger benthic foraminifera(LBF)occur throughout their history.Since the Carboniferous,LBF have thrived in carbonate-rich tropical and subtropical shallow-marine shelf environments.Their high abundance and diversity are due primarily to their extraordinary ability to inhabit a range of ecological niches and by hosting a variety of symbionts.Attaining relatively large,centimetre-scale sizes,made some forms very specialized and vulnerable to rapid ecological changes.For this reason,some LBF have shown a tendency to suffer periodically during major extinctions,especially when environmental conditions have changed rapidly and/or substantially.This,however,makes them valuable biostratigraphic microfossils and,in addition,gives invaluable insight into the spatial and temporal process of biological evolution,such as convergent/homoplasy and homology/iterative evolution.Here the evolutionary behavior of two important morphological types that occurred throughout the history of the LBF are discussed,namely the planispiral-fusiform test as typified by the fusulinids in the Late Paleozoic and the alveolinids in the Mid-Cretaceous and Neogene,and the three-layered discoid lenticular test as characterized by the orbitoids in the Mid-to Late Cretaceous,the orthophragminids in the Paleogene,and lepidocyclinids in the Oligocene to Quaternary.Understanding the propensity of these forms to convergent and iterative evolution,with the repeated re-occurrence of certain morphological features,is essential in understanding and constructing their phylogenetic relationships more generally within the main groups of the LBF.The insights gained from the history of these LBF have wider implications,and provide a more general understanding of the impacts of climate and ecological changes as driving forces for biological evolution. 展开更多
关键词 larger benthic foraminifera EXTINCTION HOMOPLASY HOMOLOGY convergent/iterative evolution climate change
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3D shape measurement of larger complex objects based on fringe cycle correction
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作者 伏燕军 杨杰 +1 位作者 王志刚 吴海涛 《Chinese Optics Letters》 SCIE EI CAS CSCD 2014年第12期42-47,共6页
The grating fringe on the reference plane is broadened in the intersecting axis system because of oblique-angle projection. In order to solve this problem, we study the theoretical model of the temporal phase unwrappi... The grating fringe on the reference plane is broadened in the intersecting axis system because of oblique-angle projection. In order to solve this problem, we study the theoretical model of the temporal phase unwrapping method based on the fringe cycle correction. We also study the 3D shape measurement theoretical model of the larger complex objects after considering the coordinate deviation and lens distortion. Experimental results demonstrate that the fringe cycle on the reference plane can be corrected to a constant value, the lens distortion can be corrected, and 3D shape of larger complex objects can be accurately measured. 展开更多
关键词 shape measurement of larger complex objects based on fringe cycle correction CYCLE CCD
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