庞塞·德莱昂发现佛罗里达

<正>Florida,the State of the USA美国佛罗里达州的州名来自西班牙语。西班牙航海家胡安·庞塞·德莱昂在1513年4月2日发现了这片地方。时值西班牙人称为Pascua Florida的节日,所以此地被德莱昂命名为La Florida。Near present-day St.Augustine,Spanish explorer Juan Ponce de Leon comes ashore1on the Florida coast,and claims the territory 2 for the Spanish crown.在今天的圣奥古斯丁(佛罗里达州东北部的港口城市)附近,西班牙探险家胡安·庞塞·德莱昂在佛罗里达州的海岸登岸,并宣称其为西班牙王室的领地。     

Prof.A.F.Revuzhenko

A. F. Revuzhenko defended the thesis and graduated from Novosibirsk state university in 1971. In 1975 he defended the PhD dissertation, and in 1984 the dissertation of doctor of sciences on mechanics of deformed solids, granular media and rocks. Since 1990 A. F. Revuzhenko is a professor on chair of Novosibirsk state university, since 1997 as the corresponding-member of the Russian academy of     

Path Selection for the Reform of Planning Management Agencies and Modernization of Spatial Governance in China

In recent years,with the profound changes of "promoting the modernization of the national governance system and capacity," the reform of state institutions has become an important measure and step.In the field of planning management,the establishment of the Ministry of Natural Resources plays a crucial role in the institutional reform over the years.This paper discusses the reform of planning management from the perspective of the public management and urban planning discipline,and tries to explore the internal logic between "institutional reform" and "governance modernization." It demonstrates the interweaving and transforming process between the adjustment of planning agencies and national governance,discussing whether the establishment of the Ministry of Natural Resources has responded to the path selection of governance modernization.The paper makes a diachronic analysis on the 13 state institutional reforms since the founding of People’s Republic of China,especially on the adjustment process of planning management agencies.It builds an "institution-governance" analysis framework with the three elements including institution,function,and management as its core and with the institutional strength and governance effectiveness as the entry and exit,and analyzes the parallel transitions of planning management agencies and spatial governance logic as well as the necessary undertaking mechanisms,with the aim to provide reference for the establishment of a new pattern of spatial governance.     

赵州桥

<正>Zhaozhou Bridge is the oldest stone arch1bridge in the world. It was built in Sui Dynasty and has the nickname"King of Bridges".赵州桥是世界上最古老的石拱桥,始建于隋朝,有"桥王"之称。Zhaozhou Bridge, also known as Anji Bridge, has an important scientific and artistic value.     

West To East: Adapting Architecture

by Paul Tan de Bibiana Rebirth is the term which most readily comes to mind to describe the phenomenal development which has overtaken China. We are seeing the latent potential of this nation being realized in the transformation of its economy, resulting in truly spectacular development opportunities.The most vivid example of this activity is the resurgence of Shanghai as the "dragon's head" of China's economic reform. Just as the 200 square miles of boggy farmland known as the Pudong New Area provided a significant opportunity to continue Shanghai's history as the "Pearl of the Orient", this city and other regions of China have provided B+H Architects International with the occasion to redefine the boundaries of its practice.     

Evaluation of the Collapsibility of Soils in the Semiarid Region of Pernambuco,Brazil

Some unsaturated soils may undergo volumetric changes when submitted to an increase in its water content or are inundated under applied loads. This behavior is related to the volumetric instability when the water content is changed. Natural collapsible soils in Brazil are generally found in alluvial, colluvial and residual soils. There are known occurrences of natural collapsible soils in many states of Brasil. In the last two decades, many public projects have been developed in areas where the occurrence of collapsible soils has been associated to geotechnical problems. The present paper devoted to study the collapsible soils in the state of Pernambuco which has been associated with large engineering projects such as housing and irrigation canals. The geotechnical investigation program included test with a field apparatus, called Expanso-colapsometer, which allows the measurement of the field settlements of a small 0.10 m of diameter plate inserted at any depth inside an auger boring hole. Reconnaissance borings with SPT （standard penetration test）, investigation pits with undisturbed block sampling and disturbed samples for laboratory tests were also made in order to assess the type and characteristics of the soil. Field tests used the Expanso-colapsometer to measure the settlement of the soil in selected depths under controlled flooding. Laboratory work included double and standard oedometer tests with a controlled rate of water inflow of 1.0 mL/s. It was found that the volume change of the soils when flooded depends on their natural stress state （vertical stress, suction head and structure of soil）.     

An extended displacement discontinuity method for analysis of stress wave propagation in viscoelastic rock mass

An extended displacement discontinuity method (EDDM) is proposed to analyze the stress wave propagation in jointed viscoelastic rock mass (VRM).The discontinuities in a rock mass are divided into two groups.The primary group with an average geometrical size larger than or in the same order of magnitude of wavelength of a concerned stress wave is defined as "macro-joints",while the secondary group with a high density and relatively small geometrical size compared to the wavelength is known as "micro-defects"...     

Practical application of failure criteria in determining safe mud weight windows in drilling operations

Wellbore instability is reported frequently as one of the most significant incidents during drilling operations.Analysis of wellbore instability includes estimation of formation mechanical properties and the state of in situ stresses.In this analysis,the only controllable parameter during drilling operation is the mud weight.If the mud weight is larger than anticipated,the mud will invade into the formation,causing tensile failure of the formation.On the other hand,a lower mud weight can result in shear failures of rock,which is known as borehole breakouts.To predict the potential for failures around the wellbore during drilling,one should use a failure criterion to compare the rock strength against induced tangential stresses around the wellbore at a given mud pressure.The Mohr–Coulomb failure criterion is one of the commonly accepted criteria for estimation of rock strength at a given state of stress.However,the use of other criteria has been debated in the literature.In this paper,Mohr–Coulomb,Hoek–Brown and Mogi–Coulomb failure criteria were used to estimate the potential rock failure around a wellbore located in an onshorefield of Iran.The log based analysis was used to estimate rock mechanical properties of formations and state of stresses.The results indicated that amongst different failure criteria,the Mohr–Coulomb criterion underestimates the highest mud pressure required to avoid breakouts around the wellbore.It also predicts a lower fracture gradient pressure.In addition,it was found that the results obtained from Mogi–Coulomb criterion yield a better comparison with breakouts observed from the caliper logs than that of Hoek–Brown criterion.It was concluded that the Mogi–Coulomb criterion is a better failure criterion as it considers the effect of the intermediate principal stress component in the failure analysis.     

编辑序语（英文）

正The Chinese New Year of 2020 is destined to be unusual, because of the unexpected outbreak of the novel coronavirus, i.e., COVID-19 as officially named, just before the Spring Festival Holiday, the most important holiday season for Chinese people. The epidemic of COVID-19 in China, which appeared later also in other parts of the world, brought about high concerns and hot debates in the fields of not only virology and medical science, but also urban planning