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Uncovering the Memories Sealed in Stones
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作者 Sun Yue Li Lin Li Xiaosu(Translated) 《China's Tibet》 2024年第4期21-25,共5页
Do stones havememories?Can theytalk?ForGewang,a conservatorwhohas dedicated tenyears toTibetan stone carvingart,theanswer is yes.Heis thrilled to witness the increasing efforts in the preservation and study of stone c... Do stones havememories?Can theytalk?ForGewang,a conservatorwhohas dedicated tenyears toTibetan stone carvingart,theanswer is yes.Heis thrilled to witness the increasing efforts in the preservation and study of stone carvings and the growing number of peoplejoining this cause. 展开更多
关键词 TIBETAN joining covering
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Uncovering the miRNA-mediated regulatory network involved in Ma bamboo(Dendrocalamus latiflorus)de novo shoot organogenesis
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作者 Nannan Wang Wenjia Wang +2 位作者 Yang Cheng Changyang Cai Qiang Zhu 《Horticulture Research》 SCIE CSCD 2023年第12期1-13,共13页
Bamboo is an important non-timber forest product and is well-known for its reluctance to regenerate.Recently we have established a de novo shoot organogenesis(DNSO)protocol in Ma bamboo(Dendrocalamus latiflorus)and re... Bamboo is an important non-timber forest product and is well-known for its reluctance to regenerate.Recently we have established a de novo shoot organogenesis(DNSO)protocol in Ma bamboo(Dendrocalamus latiflorus)and revealed the transcriptomic dynamics during Ma bamboo regeneration,which suggested the potential roles of Ma bamboo microRNAs(DlamiRNAs)in this process.However,how DlamiRNAs regulate bamboo DNSO is poorly understood.Here we performed integrated analysis with sRNAome,degradome,and transcriptome sequencing by using samples covering the four stages of the bamboo DNSO process.A total of 727 DlamiRNAs showed differential expression during the bamboo DNSO process,and the core DlamiRNA-DlamRNA-mediated regulatory networks for bamboo DNSO were constructed.Based on the results,DlamiR156 was selected for further functional characterization of its potential roles in bamboo DNSO.Transgenic bamboos with increased DlamiR156 levels exhibited an enhancement in their regeneration efficiency.Conversely,when DlamiR156 levels were downregulated,the regeneration efficiencies of transgenic bamboos decreased.Our findings show that the DlamiRNA-mediated regulatory pathways are significant in the process of bamboo regeneration and will contribute to our understanding of the molecular mechanisms governing plant organogenesis in a more comprehensive manner. 展开更多
关键词 BAMBOO BAMBOO covering
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The Research on the Psychological Tactic of Covering the Dagger With a Smile
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作者 XING Cheng 《Psychology Research》 2023年第12期600-603,共4页
Thirty-Six Stratagems is one of the most important military works of ancient China.As the name of the book,it totally includes 36 stratagems that can be used in many different fields such as military,business,and poli... Thirty-Six Stratagems is one of the most important military works of ancient China.As the name of the book,it totally includes 36 stratagems that can be used in many different fields such as military,business,and politics.Covering the dagger with a smile is one of the most common ones in these stratagems.At the same time,it is the most insidious one.As a kind of psychological tactic,it usually acts as the secret weapon of the weak.Though this stratagem should not be seen as a kind of predominant strategy,it is still worth being researched deeply,because knowing more about this psychological tactic will offer a good reference for the researchers of ancient art of war. 展开更多
关键词 psychological tactic covering the dagger with a smile Thirty-Six Stratagems
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求解Opt-Covering问题的一个降维策略
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作者 蔡宇泽 《数学学习与研究》 2013年第23期88-88,共1页
本文是对模Opt-Covering问题的降维策略进行研究.通过分块算法将原问题划分成若干子问题,然后逐一解决子问题,这样就达到降维的目的.
关键词 covering Opt-covering 连通图 降维算法
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Determination of the Thickness and Medium of Covering Soil for Land Reclamation 被引量:27
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作者 冯全洲 徐恒力 《Agricultural Science & Technology》 CAS 2009年第4期183-188,共6页
Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thic... Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thickness of covering soil and medium of covering soil to establish a self-regulating ecosystem, the thickness of covering soil of land reclamation for plants in different living forms by synusia structure of plant below-ground habitat and medium of covering soil by ecological factors of plant below-ground habitat were studied. Synusia structure of plant below-ground habitat was recognized through investigation on structure and root of plant community, and ecological factors were determined through soil profile investigation. The thickness and medium of covering soil of land reclamation for the tree, the shrub and the herb were proposed. 展开更多
关键词 Land reclamation Plant below-ground habitat Circle layer of root mass Thickness of covering soil
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求解Covering问题的拟物方法——NP难度问题的一个处理途径 被引量:16
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作者 黄文奇 《计算机学报》 EI CSCD 北大核心 1989年第8期610-616,共7页
本文提出的算法模拟了由万有引力和屏蔽现象所引起的力学过程.这种拟物的方案可为许多NP难度的问题得出有价值的近似算法.该算法对拟物类型的选择与现代递归论中的有穷损害优先方法的精神是一致的.
关键词 covering问题 NP难度 拟物方法
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Effects of Different Thicknesses of Gravel Covering on Daily Soil Evaporation 被引量:1
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作者 周约 谢铁娜 《Agricultural Science & Technology》 CAS 2015年第10期2347-2349,2353,共4页
[Objective] The research aimed to explore the most suitable gravel cover- ing thickness for selenium sand melon in arid region of central Ningxia. [Method] The natural gravel, which was from Nanshantai Region in Zhong... [Objective] The research aimed to explore the most suitable gravel cover- ing thickness for selenium sand melon in arid region of central Ningxia. [Method] The natural gravel, which was from Nanshantai Region in Zhongwei City, Ningxia, was acted as test materials to study the effects of different thicknesses of gravel covering on daily evaporation using evaporator overall weighing method. [Result] The daily evaporation capacity order of the gravel covering thickness was as follows: CK〉HI(5 cm)〉 H2(8 cm)〉 H3(10 cm)〉 H4(15 cm). Meanwhile, with the increase of test days, the difference of cumulative evaporation capacity between H3 (10 cm) and H4 (15 cm) decreased gradually. Soil evaporation capacity reduced at the pow- er function with the increase of gravel covering thickness, and the decision coeffi- cient of the fitted curve reached to 0.925 5. [Conclusion] With the increase of gravel covering thickness, evaporation capacity of soil reduced gradually, and the soil water content increased gradually. Gravel covering could effectively reduce the evapora- tion. The thicker of covering, the more obvious inhibition effect on evaporation. The thickness of covering should increase moderately to prevent moisture loss from e- vaporation. Gravel inhibition effect on the evaporation wasn't obvious when the gravel covering thickness reached more than 10 cm. 10 cm gravel covering was the most appropriate thickness for local natural condition. The soil evaporation capacity along with the change of gravel covering could be simulated with power function e- quation Y=at^b. 展开更多
关键词 Thickness Gravel covering Soil evaporation
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The Sequence-covering Compact Images of Paracompact Locally Compact Spaces 被引量:4
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作者 李进金 李克典 《Northeastern Mathematical Journal》 CSCD 2000年第4期463-468,共6页
This paper gives internal characterizations of some sequence covering compact images and compact covering compact images of paracompact locally compact spaces, which improve some results on compact images of locally... This paper gives internal characterizations of some sequence covering compact images and compact covering compact images of paracompact locally compact spaces, which improve some results on compact images of locally compact metric spaces. 展开更多
关键词 sequence covering mapping compact covering mapping compact mapping quotient mapping paracompact locally compact space cs cover sn cover cs* cover
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Light Simplified Foxtail Millet Cultivation Technique Adopting Furrow Sowing beside Plastic Film Covering Micro-ridges
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作者 夏雪岩 程汝宏 +6 位作者 宋世佳 刘猛 赵宇 任晓利 刘斐 南春梅 李顺国 《Agricultural Science & Technology》 CAS 2016年第4期869-871,876,共4页
In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and tim... In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and time saving, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated furrow sowing beside plastic film covering micro-ridges, simplified cultivation and mechanized production, forming the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges. This study introduced the technique points of the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges, including preparation before sowing,sowing, attached agricultural machines, field management, harvest and residual film recovery. 展开更多
关键词 Foxtail millet Integration of furrow sowing beside plastic film covering micro-ridges fertilization and simplified cultivation SIMPLIFICATION
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Recursive constructions for t-covering arrays
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作者 查日军 张德平 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期340-342,共3页
A t-covering array of size N, degree k, order v and strength t is an N x k array with entries from a set of v symbols such that any N x t subarray contains a t-tuple of v symbols at least once as a row. This paper pre... A t-covering array of size N, degree k, order v and strength t is an N x k array with entries from a set of v symbols such that any N x t subarray contains a t-tuple of v symbols at least once as a row. This paper presents a new algebraic recursive method for constructing covering arrays based on difference matrices. The method can extend parameter factors on the existing covering arrays and cover all the combinations of any t parameter factors (t≥2). The method, which recursively generates high strength covering arrays, is practical. Meanwhile, the theoretical derivation and realization of the proposed algebraic recursive algorithm are given. 展开更多
关键词 covering array orthogonal array difference matrix
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Properties and Relations of Several Operators Based on Covering Rough Sets
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作者 夏秀云 田浩 秦克云 《Journal of Southwest Jiaotong University(English Edition)》 2010年第2期182-187,共6页
The coveting rough sets theory is a generalization of traditional rough set theory, and can also describe information with incompleteness and fuzziness in information systems. In this paper, we first provide the defin... The coveting rough sets theory is a generalization of traditional rough set theory, and can also describe information with incompleteness and fuzziness in information systems. In this paper, we first provide the definitions of several upper and lower covering approximation operators on the covering approximation space. Then, we study the properties of these operators. Finally, we propose the mutual relations between approximation operators and similar relations of the operator ( I ) based on the covering rough sets. 展开更多
关键词 Rough sets covering rough sets covering approximation operators
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Effects of Straw Covering and Different Types of Potassium Fertilizer on Salinity Accumulation in Surface Layer of Tobacco-planted Paddy Soil 被引量:3
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作者 彭金良 雷文杰 +1 位作者 黄景崇 李迪秦 《Agricultural Science & Technology》 CAS 2013年第6期905-910,共6页
[Objective] This study aimed to investigation the effects of straw covering and different types of potassium fertilizer on salinity accumulation in surface layer of tobacco-planted paddy soil in southern China. [Metho... [Objective] This study aimed to investigation the effects of straw covering and different types of potassium fertilizer on salinity accumulation in surface layer of tobacco-planted paddy soil in southern China. [Method] Tobacco variety ‘Yunyan87’ was used as the experimental material to investigate the effects of salinity accumulation in surface layer of tobacco-planted paddy soil on the growth and development of flue-cured tobacco using different types of potassium fertilizer and mulching cultivation methods. [Result] The results showed that K+ , Ca2+ , SO42and NO3-were the major salt ions in topsoil at different growth stages of flue-cured tobacco, Na + and Mg2+ contents were also relatively high at vigorous growth stage, indicating that these salt ions were easily accumulated in surface layer of soil; to be specific, the absolute increase of salt ion concentration showed a decreasing order of K+ SO42- NO3-Ca2+ Mg2+ Na+ Cl-, while the relative increase of salt ion concentration showed a decreasing order of Ca2+ K+ Na+ NO3-SO42-Mg2+ Cl-. At 60 d posttransplanting, total salt content in topsoil reached the minimum of 359.1 mg/kg in Treatment 2, total salt content in topsoil reached the maximum of 536.1 mg/kg in Treatment 5 (CK), which was significantly higher than that in other treatments. At 90 d post-transplanting, no significant difference was observed in total salt content among various treatments. At harvesting period, total salt content in topsoil reached the maximum of 3 278.4 mg/kg in Treatment 1, which was significantly higher than that in other treatments. Topsoil pH showed no significant differences among various treatments at three different periods, ranging from 5.39 to 5.59. Straw covering could effectively reduce salt content in topsoil, accelerate vigorous growth of tobacco, shorten vigorous growth period and increase plant height, leaf number and lead area; at vigorous growth stage, root vitality and root volume of tobacco were improved, but the yield and output value were relatively low. Major agronomic traits and yield of tobacco showed no significant difference among various treatments. Output value of tobacco reached the maximum of 24 196.8 yuan/hm2 in Treatment 3, which was significantly higher than that in other treatments. [Conclusion] Appropriate types and proportions of potassium fertilizer and straw covering can effectively reduce the total salt content in tobacco-planted paddy soil and increase the effective supply amount of K+ , Ca2+ , SO42-and NO3-, thereby promoting and improving the root vitality of tobacco, which is conducive to the growth and development of tobacco and will eventually enhance the yield, quality and economic benefits of flue-cured tobacco. 展开更多
关键词 Flue-cured tobacco Tobacco-planted paddy soil Salinity accumulation in surface layer Potassium fertilizer Straw covering
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GF(2)上向量的相对长度,Packing及Covering界
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作者 孙广人 《安庆师范学院学报(自然科学版)》 2011年第3期19-21,共3页
本文证明向量的相对长度与Hamming距离非常类似,即在一定条件下也存在packing与covering界。
关键词 相对长度 最大长度 PACKING covering
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Minimum Covering RandićEnergy of a Graph
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作者 M. R. Rajesh Kanna R. Jagadeesh 《Advances in Linear Algebra & Matrix Theory》 2016年第4期116-131,共17页
Randi&cacute;energy was first defined in the paper [1]. Using minimum covering set, we have introduced the minimum covering Randi&cacute;energy RE<sub>C</sub> (G) of a graph G in this paper. This p... Randi&cacute;energy was first defined in the paper [1]. Using minimum covering set, we have introduced the minimum covering Randi&cacute;energy RE<sub>C</sub> (G) of a graph G in this paper. This paper contains computation of minimum covering Randi&cacute;energies for some standard graphs like star graph, complete graph, thorn graph of complete graph, crown graph, complete bipartite graph, cocktail graph and friendship graphs. At the end of this paper, upper and lower bounds for minimum covering Randi&cacute;energy are also presented. 展开更多
关键词 Minimum covering Set Minimum covering Randi&cacute MATRIX Minimum covering Randi&cacute EIGENVALUES Minimum covering Randi&cacute ENERGY
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Metaheuristic post-optimization of the NIST repository of covering arrays
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作者 Jose Torres-Jimenez Arturo Rodriguez-Cristerna 《CAAI Transactions on Intelligence Technology》 2017年第1期31-38,共8页
Construction of Covering Arrays (CA) with minimum possible number of rows is challenging. Often the available CA have redundant combinatorial interaction that could be removed to reduce the number of rows. This pape... Construction of Covering Arrays (CA) with minimum possible number of rows is challenging. Often the available CA have redundant combinatorial interaction that could be removed to reduce the number of rows. This paper addresses the problem of removing redundancy of CA using a metaheuristic post- optimization (MPO) approach. Our approach consists of three main components: a redundancy detector (RD); a row reducer (RR); and a missing-combinations reducer (MCR). The MCR is a metaheuristic component implemented using a simulated annealing algorithm. MPO was instantiated with 21,964 CA taken from the National Institute of Standards and Technology (NIST) repository. It is a remarkable result that this instantiation of MPO has delivered 349 new upper bounds for these CA. 展开更多
关键词 covering arrays NIST repository of covering arrays Metaheuristic post-processing algorithms
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Clinical observation of removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis 被引量:8
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作者 Guang-Hua Sun, Wei-Yun Shi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第1期88-91,共4页
AIM: To study the clinical observation of removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis. METHODS:A retrospect... AIM: To study the clinical observation of removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis. METHODS:A retrospective study was done to 10 patients (10 eyes) who had accepted removal of the necrotic corneal tissue combined with conjunctival flap covering surgery for fungal keratitis,the diagnosis by corneal scraping and smear examination or confocal microscopy check hyphae. Local and systemic antifungal therapy more than one week for all patients, corneal ulcer enlarge or no shrink. Slit lamp microscope examination the diameter of corneal ulcer about 2mm-4mm. Anterior segment optical coherence tomography (AS-OCT)examine the depth of corneal ulcer between 1/3-1/2, infiltrate corneal stroma about 20um-80um,the diameter of corneal ulcer about 3mm-6mm.Type-B ultrasonic exclusion endophthalmitis. Complete removal lesions until transparent of stoma, make conjunctival flap equal or greater than ulcer 1mm nearby conjunctiva. Continued antifungal therapy. The vision, fungal recurrence, conjunctival flap rollback or desquamate were analysed. ' RESULTS:Ten patients had success done this surgery, the corneal ulcer was not enlarge and healing afteroperation. 7 cases were bridging conjunctival flap and 3cases were single conjunctival flap. Preoperation vision above 0.1 had 8 cases,7 cases had vision above 0.1 one week after surgery, while 1 cases vision droped from 0.3 to 0.05.There was not recurrent for fungal,2 cases conjunctival flap rollback:1 case was bridging and 1case was single flap, no conjunctival flap desquamate. CONCLUSION: It is safe and effective to perform removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis which werenot sensitive or aggravate for antifungal drugs. 展开更多
关键词 AS-OCT removal of the necrotic corneal tissue conjunctival flap covering surgery fungal keratitis
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SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE 被引量:5
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作者 YUJun-bao LIUJing-shuang 《Chinese Geographical Science》 SCIE CSCD 2002年第3期268-272,共5页
Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp le... Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp les are taken at different locations,inclu ding three kinds of covering soil,th ree different depths of soil layers a nd four different covering ages of covering soil.The s patial-temporal variation of heavy metal element content in reclamatio n soil is stud-ied.The results indicate that the co ntent of heavy metal elements is decreasing year after year;the determin ant reason why the content of heavy metal elemen ts at 60cm depth layer is higher than t hat at 30cm depth layer and surface is fertiliz-er and manure application;the metal elements mainly come from external environment;there is no metal pollut ion coming from mother material(coal mining wastes)in plough layer of covering soil. 展开更多
关键词 covering soil heavy metal elements spatial-temporal variation RECLAMATION fushun coal mine
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Effects of V-pits covering layer position on the optoelectronic performance of InGaN green LEDs 被引量:3
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作者 Chen Xu Changda Zheng +4 位作者 Xiaoming Wu Shuan Pan Xingan Jiang Junlin Liu Fengyi Jiang 《Journal of Semiconductors》 EI CAS CSCD 2019年第5期61-65,共5页
The impact of the V-pits covering layer(VCL) position on the optoelectronic performance of InGaN-based green light-emitting diodes(LEDs) was investigated. It is found that earlier covering of V-pits will hinder the ho... The impact of the V-pits covering layer(VCL) position on the optoelectronic performance of InGaN-based green light-emitting diodes(LEDs) was investigated. It is found that earlier covering of V-pits will hinder the hole injection via the sidewall of V-pits, and then result in less quantum wells(QWs) participating in radioluminescence. The current-voltage characteristics show that the LEDs with earlier covering of V-pits have higher operating voltage at room temperature, and a more dramatic voltage rise with the reduction of temperature. Meanwhile, more manifested emission peaks for sidewall QWs and deeper QWs near to ntype layer was observed in the sample with earlier coveing of V-pits at cryogenic temperatures, for the reason that the holes being injected via V-pits sidewall have higher kinetic energy and could transport to deeper QWs. 展开更多
关键词 green LIGHT-EMITTING DIODES V-pits covering layer hole injection efficiency operating voltage
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ON THE SHARP GROWTH,COVERING THEOREMS FOR NORMALIZED BIHOLOMORPHIC MAPPINGS IN C^n 被引量:2
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作者 刘小松 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期803-812,共10页
In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almos... In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almost starlike mappings of order α and starlike mappings of order α are established. Meanwhile, the construction of the above mappings on bounded starlike circular domain in Cn is also discussed, it provides the extremal mappings for the growth, covering theorems of the above mappings. 展开更多
关键词 Zero of order k 1 normalized biholomorphic mappings almost starlike mappings of order α starlike mappings of order α GROWTH covering theorems
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Gravity-based heuristic for set covering problems and its application in fault diagnosis 被引量:2
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作者 Yun Li Zhiming Cai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期391-398,共8页
A novel algorithm named randomized binary gravita- tional search (RBGS) algorithm is proposed for the set covering problem (SCP). It differs from previous SCP approaches because it does not work directly on the SC... A novel algorithm named randomized binary gravita- tional search (RBGS) algorithm is proposed for the set covering problem (SCP). It differs from previous SCP approaches because it does not work directly on the SCP matrix. In the proposed algo- rithm, the solution of SCP is viewed as multi-dimension position of objects in the binary search space. All objects in the space attract each other by the gravity force, and this force causes a global movement of all objects towards the objects with heavier masses which correspond to good solutions. Computation results show that the proposed algorithm is very competitive. In addition, the proposed aigodthm is extended for SCP to solve the fault diagno- sis problem in graph-based systems. 展开更多
关键词 set covering problem (SCP) gravity force binary search space fault diagnosis.
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