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TWO NEW SPECIES AND ONE NEW COMBINATION OF THE CONIFER SAWFLY FAMILY DIPRIONIDAE (HYMENOPTERA: SYMPHYTA) FROM YUNNAN, CHINA 被引量:3
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作者 徐正会 《Zoological Research》 CAS CSCD 1997年第2期171-176,共6页
In this paper two new species of Diprionidae were described from Yunnan Province, China, Gilpinia hebedentata, sp. n. and Macrodiprion wui, sp. n. Another species recorded in Yunnan, Gilpinia disa Smith, was transferr... In this paper two new species of Diprionidae were described from Yunnan Province, China, Gilpinia hebedentata, sp. n. and Macrodiprion wui, sp. n. Another species recorded in Yunnan, Gilpinia disa Smith, was transferred from Gilpinia Benson to Microdiprion Enslin. Macrodiprion Enslin is a newly recorded genus in China. 展开更多
关键词 HYMENOPTERA Diprionidae new species new combination YUNNAN China
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Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s
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作者 Vladimir I.Kolpakov Sergey V.Fedorov +1 位作者 Ekaterina P.Vinogradova Irina A.Bolotina 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期126-135,共10页
Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters ... Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness. 展开更多
关键词 Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation
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Fracture propagation and evolution law of indirect fracturing in the roof of broken soft coal seams
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作者 Haifeng Zhao Pengyue Li +1 位作者 Xuejiao Li Wenjie Yao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期78-102,共25页
Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings ... Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings of true triaxial hydraulic fracturing experiments and field pilot under this technology and the cohesive element method,a 3D numerical model of indirect fracturing in the roof of broken soft coal seams was established,the fracture morphology propagation and evolution law under different conditions was investigated,and analysis of main controlling factors of fracture parameters was conducted with the combination weight method,which was based on grey incidence,analytic hierarchy process and entropy weight method.The results show that“士”-shaped fractures,T-shaped fractures,cross fractures,H-shaped fractures,and“干”-shaped fractures dominated by horizontal fractures were formed.Different parameter combinations can form different fracture morphologies.When the coal seam permeability is lower and the minimum horizontal principal stress difference between layers and fracturing fluid injection rate are both larger,it tends to form“士”-shaped fractures.When the coal seam permeability and minimum horizontal principal stress between layers and perforation position are moderate,cross fractures are easily generated.Different fracture parameters have different main controlling factors.Engineering factors of perforation location,fracturing fluid injection rate and viscosity are the dominant factors of hydraulic fracture shape parameters.This study can provide a reference for the design of indirect fracturing in the roof of broken soft coal seams. 展开更多
关键词 Indirect fracturing Roof of coal seam Fracture propagation and evolution Coalbed methane Cohesive element method combination weight method
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Climate change vulnerability assessment in the new urban planning process in Tanzania
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作者 Issa NYASHILU Robert KIUNSI Alphonce KYESSI 《Regional Sustainability》 2024年第3期1-11,共11页
Climate change vulnerability assessment is an essential tool for identifying regions that are most susceptible to the impacts of climate change and designing effective adaptation actions that can reduce vulnerability ... Climate change vulnerability assessment is an essential tool for identifying regions that are most susceptible to the impacts of climate change and designing effective adaptation actions that can reduce vulnerability and enhance long-term resilience of these regions.This study explored a framework for climate change vulnerability assessment in the new urban planning process in Jangwani Ward,Tanzania.Specifically,taking flood as an example,this study highlighted the steps and methods for climate change vulnerability assessment in the new urban planning process.In the study area,95 households were selected and interviewed through purposeful sampling.Additionally,10 respondents(4 females and 6 males)were interviewed for Focus Group Discussion(FGD),and 3 respondents(1 female and 2 males)were selected for Key Informant Interviews(KII)at the Ministry of Lands,Housing and Human Settlements Development.This study indicated that climate change vulnerability assessment framework involves the assessment of climatic hazards,risk elements,and adaptive capacity,and the determination of vulnerability levels.The average hazard risk rating of flood was 2.3.Socioeconomic and livelihood activities and physical infrastructures both had the average risk element rating of 3.0,and ecosystems had the average risk element rating of 2.9.Adaptive capacity ratings of knowledge,technology,economy or finance,and institution were 1.6,1.9,1.4,and 2.2,respectively.The vulnerability levels of socioeconomic and livelihood activities and physical infrastructure were very high(4.0).Ecosystems had a high vulnerability level(3.8)to flood.The very high vulnerability level of socioeconomic and livelihood activities was driven by high exposure and sensitivity to risk elements and low adaptive capacity.The study recommends adoption of the new urban planning process including preparation,planning,implementation,and monitoring-evaluation-review phases that integrates climate change vulnerability assessment in all phases. 展开更多
关键词 Climate change Vulnerability level Climatic hazard Risk elements Adaptive capacity new urban planning PROCESS
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Taxonomic notes of theridiid spiders (Araneae: Theridiidae) from China and Vietnam
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作者 Ye-Jie Lin Chang-Hao Hu +1 位作者 Dinh-Sac Pham Shu-Qiang Li 《Zoological Research(Diversity and Conservation)》 2024年第2期141-168,共28页
Ten new species of the spider family Theridiidae Sundevall,1833 from China and Vietnam are described:Chrysso shantinggui sp.nov.(♂♀),Gushangzao andaoquan sp.nov.(♂),Moneta oupeng sp.nov.(♂♀),Phycosoma yanshun sp.... Ten new species of the spider family Theridiidae Sundevall,1833 from China and Vietnam are described:Chrysso shantinggui sp.nov.(♂♀),Gushangzao andaoquan sp.nov.(♂),Moneta oupeng sp.nov.(♂♀),Phycosoma yanshun sp.nov.(♂♀),Spinembolia gaofani sp.nov.(♀),S.jiangjing sp.nov.(♂♀),S.lingzhen sp.nov.(♂♀),Stemmops dengfei sp.nov.(♂♀),Takayus xiaorang sp.nov.(♂♀),Yaginumena weidingguo sp.nov.(♀).The unknown sexes of Allothymoites sculptilis Gao&Li,2014,Gyro zeppeli Lin&Li,2024,Parasteatoda longiducta Zhu,1998 are described for the first time. 展开更多
关键词 DIAGNOSIS new combination new species ASIA
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A POSTERIORI ERROR ESTIMATION OF THE NEW MIXED ELEMENT SCHEMES FOR SECOND ORDER ELLIPTIC PROBLEM ON ANISOTROPIC MESHES
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作者 王培珍 陈绍春 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1510-1518,共9页
This paper presents a posteriori residual error estimator for the new mixed el-ement scheme for second order elliptic problem on anisotropic meshes. The reliability and efficiency of our estimator are established with... This paper presents a posteriori residual error estimator for the new mixed el-ement scheme for second order elliptic problem on anisotropic meshes. The reliability and efficiency of our estimator are established without any regularity assumption on the mesh. 展开更多
关键词 error estimator anisotropic meshes new mixed element schemes
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Research on the path of medical service combination from the perspective of departmental cooperation
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作者 YANG Huazhen 《International English Education Research》 2018年第3期59-61,共3页
As an innovative mode of social endowment, combining medical care with modern medical care technology and old-age service is an important direction of a series of social problems caused by the deepening of aging and t... As an innovative mode of social endowment, combining medical care with modern medical care technology and old-age service is an important direction of a series of social problems caused by the deepening of aging and the intensification of aging process in China. It is the inevitable choice for the development of Chinese characteristics for the aged. At present, with the continuous development of the combination of medical care and rehabilitation, the process of combination of medical care and breeding is slow, and the problems of inter departmental cooperation, high cost of resource integration and low service efficiency have emerged. The paper puts forward that multi head management of different responsibility management body is a bottleneck problem that hinders the integration of medical care. From the objective and subjective two points of view, the administrative system level barrier and the inter departmental interest game are the important reasons that obstruct the medical support and break through the estrangement of the Department and realize the cooperation. Then, according to the theory of large part system reform, the author boldly proposes the idea of establishing a new comprehensive functional department that specializes in the management of pension related affairs. 展开更多
关键词 medical service combination new pension service mode department cooperation bottleneck problem
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Research on Chinese Education Philosophy of "Truth, Kindness, and Aesthetics Combination "
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作者 龚丹 《海外英语》 2011年第15期95-97,共3页
Chinese Education Philosophy of "Truth, Kindness, and Aesthetics Combination" manifests in the research on Chinese education from aesthetics perspective. It aims at the "narrow and limited view" of... Chinese Education Philosophy of "Truth, Kindness, and Aesthetics Combination" manifests in the research on Chinese education from aesthetics perspective. It aims at the "narrow and limited view" of "not the general aesthetics, but the artistic beauty only", and it aims at biased opinion of "the interest saying", "the fine arts saying", "the esthetic sense saying" on aesthetics. It also aims at serious distraction of "LEFT in form but RIGHT in essence" of the mainstream ideology "the thought", "the revolution", "politics" and so on. It is a complex study of Chinese education from the philosophy of the unity of Truth, Kindness, and Aesthetics of oriental aesthetics, the consensus of Truth, Kindness, and Aesthetics of Western aesthetics, and the identity of Truth, Kindness, and Aesthetics of Marx aesthetics. From aesthetics perspective, it studies Chinese education, "combing" the reversed relationships among "truth", "kindness" and "aesthetics" in Chinese, adopting the methods of "research with great ease", "cases study", and "combination of ration and perception", to achieve "truth" of in Chinese, "kindness" of and "aesthetics" of , promote the development of "Chinese intellectual education", "Chinese moral education", and "Chinese aesthetic education" harmoniously, to realize the "Truth, Kindness, and Aesthetics Combination" of Chinese education and to reach the brand-new boundary territory of "human development and integrity construction" effectively. 展开更多
关键词 Chinese education PHILOSOPHY Truth Kindness and AEStheTICS combination Ideal target Brand-new boundary territory
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STUDY ON THE GENUS ORALIA MALAISE (HYMENOPTERA: TENTHREDINIDAE) OF CHINA ①
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作者 魏美才 聂海燕 《Entomotaxonomia》 CSCD 1998年第4期291-296,共6页
The genus Oralia Malaise is recorded from China with three species described as new to science: Oralia fulva sp. nov., Oralia acuritheca sp. nov., Oralia tibetana sp. nov.. The genus Himindica Sain... The genus Oralia Malaise is recorded from China with three species described as new to science: Oralia fulva sp. nov., Oralia acuritheca sp. nov., Oralia tibetana sp. nov.. The genus Himindica Saini, 1996 is treated as junior synonym of Oralia Malaise, 1961. Two new specific synonyms and two new combinations are proposed: Oralia nigroclypeata Malaise, 1961 = Himindica nigrothorax Saini et Vasu, 1997, syn. nov., Oralia fossulata Malaise, 1961 = Himindica maculipleuris Saini et Vasu, 1997, syn. nov.; Oralia himalayaensis (Saini et Deep, 1991), comb. nov., Oralia meghalayaensis (Saini et Vasu, 1997), comb. nov. A synoptic key is also provided for the known species of Oralia Malaise. 展开更多
关键词 HYMENOPTERA TENTHREDINIDAE Oralia new species new synonyms new combinations
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A New Combination and Two Varieties of Polystigmate Gomphonema (Gomphonemaceae Bacillariophyta) from Heilongjiang Province, China 被引量:2
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作者 范亚文 施之新 +1 位作者 包文美 王全喜 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第2期198-203,共6页
The authors discribed a new polystigmate combination, Gomphonema turris Ehr. var. okamurae (Skv.) Fan et Bao.comb.nov., and two new varieties, Gomphonema turris Ehr. var. latum Fan et Wang. var. nov. and Gomphonema ac... The authors discribed a new polystigmate combination, Gomphonema turris Ehr. var. okamurae (Skv.) Fan et Bao.comb.nov., and two new varieties, Gomphonema turris Ehr. var. latum Fan et Wang. var. nov. and Gomphonema acuminatum var. obtusum Fan et Bao, var. nov., that were distinguished by frustule morphology under LM. The samples were collected from freshwater of Heilongjiang Province, China. 展开更多
关键词 new combination new varieties polystigmate Gomphonema Heilongjiang
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Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System
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作者 LI Yan-wei LIU Xiu-quan +3 位作者 WANG Jin-long CHEN Guo-ming CHANG Yuan-jiang SHENG Lei-xiang 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期29-41,共13页
The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of risers.This approach leads to... The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of risers.This approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex constraints.To accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβmethod.An analysis program is also developed in MATLAB for dynamic simulation.The simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation joint.The bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and application.The platform navigation speed range under the safety limits of risers expands with the new hang-off system in use. 展开更多
关键词 deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method
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A coupled cryogenic thermo-hydro-mechanical model for frozen medium:Theory and implementation in FDEM
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作者 Lei Sun Xuhai Tang +3 位作者 Kareem Ramzy Aboayanah Qi Zhao Quansheng Liu Giovanni Grasselli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4335-4353,共19页
This paper presents the development of a coupled modeling approach to simulate cryogenic thermo-hydro-mechanical(THM)processes associated with a freezing medium,which is then implemented in the combined finite-discret... This paper presents the development of a coupled modeling approach to simulate cryogenic thermo-hydro-mechanical(THM)processes associated with a freezing medium,which is then implemented in the combined finite-discrete element method code(FDEM)for multi-physics simulation.The governing equations are deduced based on energy and mass conservation,and static equilibrium equations,considering water/ice phase change,where the strong couplings between multi-fields are supplemented by critical coupling parameters(e.g.unfrozen water content,permeability,and thermal conductivity).The proposed model is validated against laboratory and field experiments.Results show that the cryogenic THM model can well predict the evolution of strongly coupled processes observed in frozen media(e.g.heat transfer,water migration,and frost heave deformation),while also capturing,as emergent properties of the model,important phenomena(e.g.latent heat,cryogenic suction,ice expansion and distinct three-zone distribution)caused by water/ice phase change at laboratory and field scales,which are difficult to be all revealed by existing THM models.The novel modeling framework presents a gateway to further understanding and predicting the multi-physical coupling behavior of frozen media in cold regions. 展开更多
关键词 thermo-hydro-mechanical(THM)coupling Low temperature Heat transfer Water migration Frost heave Combined finite-discrete element method(FDEM)
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The identity of Dinochloa species and enumeration of Melocalamus(Poaceae:Bambusoideae) in China 被引量:1
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作者 Jing-Xia Liu Zu-Chang Xu +2 位作者 Yu-Xiao Zhang Meng-Yuan Zhou De-Zhu Li 《Plant Diversity》 SCIE CAS CSCD 2023年第2期133-146,共14页
Three woody bamboo species collected in Hainan,China in 1940 have been described as Dinochloa based on vegetative specimens.However,the identity of these species has long been in doubt,largely because the vegetative p... Three woody bamboo species collected in Hainan,China in 1940 have been described as Dinochloa based on vegetative specimens.However,the identity of these species has long been in doubt,largely because the vegetative phase in species of Dinochloa is morphologically similar to that in species of Melocalamus,a climbing or scrambling bamboo genus of the paleotropical woody bamboos(Poaceae:Bambusoideae)that consists of about 15 species and one variety.To determine the phylogenetic affinity of the three Dinochloa species from Hainan,we sampled almost all recognized Chinese species of Melocalamus and representative species of Dinochloa as well as other closely related genera,performed molecular phylogenetic analysis,and compared their morphology based on herbarium and fieldwork investigation.Our ddRAD data indicate that the three species from Hainan are closely related to Melocalamus,not Dinochloa.Morphological analysis showed that these three species have a climbing habit but do not grow spirally,their culm leaves have smooth bases,and there is a ring of powder and/or tomenta above and below the nodes.Taken together our findings indicate that the three species from Hainan originally published in Dinochloa should be transferred to Melocalamus,i.e.,Melocalamus orenudus(McClure) D.Z.Li& J.X.Liu,Melocalamus puberulus(McClure) D.Z.Li & J.X.Liu,and Melocalamus utilis(McClure) D.Z.Li &J.X.Liu,respectively.This study concludes with an enumeration of Chinese species of Melocalamus,with a key to nine recognized species and one variety,and a lectotypification for M. compatiflorus. 展开更多
关键词 ddRAD Melocalamus orenudus Melocalamus puberulus Melocalamus utilis new combinations Lectotypification
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Numerical simulation on the seismic performance of retrofitted masonry walls based on the combined finite-discrete element method 被引量:1
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作者 Wu Biye Dai Junwu +2 位作者 Jin Huan Bai Wen Chen Bowen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期777-805,共29页
Due to the long construction life,improper design methods,brittle material properties and poor construction techniques,most existing masonry structures do not perform well during earthquakes.The retrofitting method us... Due to the long construction life,improper design methods,brittle material properties and poor construction techniques,most existing masonry structures do not perform well during earthquakes.The retrofitting method using an external steel-meshed mortar layer is widely used to retrofit existing masonry buildings.Assessing the seismic performance of masonry walls reinforced by an external steel-meshed mortar layer reasonably and effectively is a difficult subject in the research field of masonry structures.Based on the combined finite-discrete elements method,the numerical models of retrofitted brick walls with four different masonry mortar strengths by an external mortar layer are established.The shear strength of mortar and the contact between the retrofitted mortar layer and the brick blocks are discussed in detail.The failure patterns and load-displacement curves of the retrofitted brick walls were obtained by applying low cycle reciprocating loads to the numerical model,and the bearing capacity and the failure mechanism of the retrofitted walls were obtained by comparing the failure patterns,ultimate bearing capacity,deformability and other aspects with the tests.This study provides a basis for improving the seismic strengthening design method of masonry structures and helps to better assess the seismic performance of masonry structures after retrofitting. 展开更多
关键词 masonry wall external steel-meshed mortar layer combined finite-discrete element method hysteretic curve ultimate bearing capacity
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Geotechnical investigations and remediation design for failure of tunnel portal section: a case study in northern Turkey 被引量:7
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作者 Ayberk KAYA Kadir KARAMAN Fikri BULUT 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1140-1160,共21页
Mass movements are very common problems in the eastern Black Sea region of Turkey due to its climate conditions, geological, and geomorphological characteristics. High slope angle, weathering, dense rainfalls, and ant... Mass movements are very common problems in the eastern Black Sea region of Turkey due to its climate conditions, geological, and geomorphological characteristics. High slope angle, weathering, dense rainfalls, and anthropogenic impacts are generally reported as the most important triggering factors in the region. Following the portal slope excavations in the entrance section of Cankurtaran tunnel, located in the region, where the highly weathered andesitic tuff crops out, a circular toe failure occurred. The main target of the present study is to investigate the causes and occurrence mechanism of this failure and to determine the feasible remedial measures against it using finite element method(FEM) in four stages. These stages are slope stability analyses for pre-and postexcavation cases, and remediation design assessments for slope and tunnel. The results of the FEM-SSR analyses indicated that the insufficient initial support design and weathering of the andesitic tuffs are the main factors that caused the portal failure. After installing a rock retaining wall with jet grout columns and reinforced slope benching applications, the factor of safety increased from 0.83 to 2.80. In addition toslope stability evaluation, the Rock Mass Rating(RMR), Rock Mass Quality(Q) and New Austrian Tunneling Method(NATM) systems were also utilized as empirical methods to characterize the tunnel ground and to determine the tunnel support design. The performance of the suggested empirical support design, induced stress distributions and deformations were analyzed by means of numerical modelling. Finally, it was concluded that the recommended stabilization technique was essential for the dynamic long-term stability and prevents the effects of failure. Additionally, the FEM method gives useful and reasonably reliable results in evaluating the stability of cut slopes and tunnels excavated both in continuous and discontinuous rock masses. 展开更多
关键词 Portal failure Stability analysis Finite element method Tunnel support design Remedial measures Rock Mass Rating(RMR) Rock Mass Quality(Q) new Austrian Tunneling Method(NATM)
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New Finite Elements in Shear Stress Analysis of Saint Venant′s Torsional Loaded Beam Structures
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作者 J. Brnic G. Turkalj 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第z1期151-153,共3页
Recent engineering design as well as material processing on the optimization procedure are based and computeroriented. Finite element stress and sensitivity analysis are the most important things in such modern determ... Recent engineering design as well as material processing on the optimization procedure are based and computeroriented. Finite element stress and sensitivity analysis are the most important things in such modern determinationof optimal solution. According to high computer capacity finite element continuum discretization and load applicationindependent of the coming fields become unlimited. This paper deals with the development of a new finite elementsgeneration used in shear stress analysis caused by S.Venant′s torsional load and bending with shear. Their stiffnessmatrices and load vectors on the basis of their geometrical properties are derived. For justification of new finiteelements application some examples are presented. 展开更多
关键词 new FINITE elements SHEAR stress analysis Optimal design
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New Combination of Semilate Rice: Yuanliangyou 1000
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作者 Jinhe HU Guoxiang LIU +3 位作者 Qiyun DENG Xiaojing WU Shuwen HE Fei ZHU 《Agricultural Biotechnology》 CAS 2018年第6期74-77,80,共5页
Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng... Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng Agricultural Development Co.,Ltd.It passed through new variety certification of Jiangxi Province in 2017,and approval number was Ganshendao 20170020,which was suitable for plantation of semilate rice in Jiangxi.In this paper,breeding process,combination characteristic,main cultivation technique and seed production technology of Yuanliangyou 1000 were introduced. 展开更多
关键词 Semilate RICE new combination Yuanliangyou 1000 BREEDING PROCESS
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The ecosystem of Lake Kenon:past and present(Transbaikal Territory,Russia)
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作者 Alexey P.KUKLIN Gazhit Ts.TSYBEKMITOVA +2 位作者 Evgenia P.GORLACHEVA Balzhit B.BAZAROVA Alexey V.AFONIN 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第3期507-516,共10页
Present-day conditions of the Lake Kenon ecosystem are determined by a combination of natural and anthropogenic factors. We have estimated the effects of a complex of factors on the condition of the abiotic environmen... Present-day conditions of the Lake Kenon ecosystem are determined by a combination of natural and anthropogenic factors. We have estimated the effects of a complex of factors on the condition of the abiotic environment and on specific biological components in the lake ecosystem. Change in biogenic load has caused an increase in the role of phytoplankton in the general balance of organic matter during the high-water period. Charophytes are the main dominants of bottom vegetation. Anthropogenic load has caused a decrease in both fish species and fish capacity. The lake application as a water reservoir-cooler has influenced the average annual water mineralization (from 420 mg/L to 530.0 mg/L with a maximum 654 mg/L in 1993) and fluctuations in its hydrochemical composition. The present composition of the lake is sulfate-hydrocarbonate-chloride calcium-sodic-magnesium in character. S(Y44 content is twice as much as the maximum permissible concentration in fishery waters. Water drainage from an ash disposal area to the lake has caused an increase in chemical-element concentrations including the heavy metals. Hg concentration in Perca fluviatilis muscles is 0.5 9g/g dry wt. Thus, understanding directions in the ecosystem of the water reservoir-cooler under changing hydrological conditions will let us forecast the consequences of new combined heat and power plant operation. 展开更多
关键词 water reservoir-cooler of combined heat and power plant (CHP) HYDROCHEMISTRY ICHTHYofAUNA BIODIVERSITY the chemical elements
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Maxwell’s Equations as the Basis for Model of Atoms
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作者 Milan Perkovac 《Journal of Applied Mathematics and Physics》 2014年第5期235-251,共17页
A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can... A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can derive Schr&ouml;dinger’s equation, which is the foundation of quantum physics. The equations for energy, momentum, frequency and wavelength of the electromagnetic wave in the atom are derived using the model of atom by analogy with the transmission line. The action constant A0 = (μ0/ε0)1/2s02e2 is a key term in the above mentioned equations. Besides the other well-known constants, the only unknown constant in the last expression is a structural constant of the atom s0. We have found that the value of this constant is 8.277 56 and that it shows up as a link between macroscopic and atomic world. After calculating this constant we get the theory of atoms based on Maxwell’s and Lorentz equations only. This theory does not require knowledge of Planck’s constant h, which is replaced with theoretically derived action constant A0, while the replacement for the fine structure constant α-1 is theoretically derived expression 2s02 = 137.036. So, the structural constant s0 replaces both constants h and α. This paper also defines the stationary states of atoms and shows that the maximal atomic number is equal to Zmax = 137. The presented model of the atoms covers three of the four fundamental interactions, namely the electromagnetic, weak and strong interactions. 展开更多
关键词 Action CONSTANT Fine Structure CONSTANT Lecher’s LINE Maxwell’s Equations new elements Phase Velocity Planck’s CONSTANT Stability of ATOMS Standing Waves Stationary STATES Synchronized STATES System of the elements STRUCTURAL Coefficient STRUCTURAL CONSTANT Transmission LINE Undiscovered elements
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Comparative Test of New Late Indica Hybrid Rice Combinations with Good Quality
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作者 Jinhe HU Fei ZHU +2 位作者 Xiaolin CHENG Yuping HU Fengqin YU 《Agricultural Biotechnology》 CAS 2021年第4期20-24,共5页
[Objectives]This study was conducted to screen rice varieties suitable for planting in Nanchang City with high quality,high yield,good yield,and strong disease and stress resistance.[Methods]Seven new late indica hybr... [Objectives]This study was conducted to screen rice varieties suitable for planting in Nanchang City with high quality,high yield,good yield,and strong disease and stress resistance.[Methods]Seven new late indica hybrid rice combinations with good quality bred in Jiangxi Province in recent years and seven new late indica hybrid rice combinations with good quality bred by Nanchang Academy of Agricultural Sciences were introduced,and compared with Tianyouhuazhan as a control.[Results]The rice quality and taste of the tested combinations were better than those of the control.Among the tested combinations,Yuliangyoufuxiangzhan,Xintaiyousizhan,Yuxiangliangyou No.8 and Guangheyou 33 had good stress resistance,high yield and good rice quality.[Conclusions]This study provides a theoretical basis for the selection and breeding of new rice varieties in Nanchang City. 展开更多
关键词 Good-quality late indica rice Hybrid rice new combination Comparative test
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