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71.
A software prototype of a simulation service software environment, called DOSE (distributed object‐based software environment), is developed to realize the integrated simulation of an urban system under the risk of urban‐scale hazards such as earthquakes. DOSE infrastructure is built on three basic building blocks, namely: modularity, scalability, and interoperability. In this paper, the application of DOSE to real‐world urban systems is described in order to provide an evidence for DOSE modularity and scalability. An overview of DOSE is presented and then followed by a beverage application to simulate earthquake hazard in an urban system. The urban system is developed for the city of Kobe (Kobe district) with dimensions of 700 × 500 (m) and Bunkyo ward (Tokyo district) with dimensions of 800 × 600 (m) where DOSE simulation participants are identified for each district. The effectiveness of data exchange among different participants through a distributed service exchange network is described as an evidence for DOSE modularity that facilitates the integration process. On the other hand, the effectiveness of processing time when applying the simulation to different urban system sizes and/or using different third‐party applications is described as an evidence for DOSE scalability. The details of the underlying infrastructure of DOSE are beyond the scope of this paper and are presented in an accompanying paper work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
72.
In this paper, a distributed object‐based software environment (DOSE) has been developed to facilitate the integrated simulation of an urban system under the risk of urban‐scale hazards such as earthquakes. It is understood that individual simulation participants perform their simulation services in separate environments, bartering service exchange relationships to get what they need to resolve their part of the problem. This is the communication gap between the scientists on one side and the end users who need to understand knowledge and employ it on the other side. The authors envision a distributed simulation service software environment running in parallel with the activities of simulation participants. DOSE has lent itself to integrate interdisciplinary participants through an infrastructure that has three basic building blocks, namely: modularity, scalability, and interoperability. The modular, object‐based, design of DOSE architecture is described in terms of key functionalities of four distinct layers, namely: resource, core, domain, and interface layers. DOSE scalability in terms of urban system size and participant third‐party application complexity is enabled through the interface layer. A message passing model is developed using the Message Passing Interface standard and a control room is provided to schedule the interaction/communication among model processes. DOSE interoperability with the vulnerability analysis third‐party applications is enabled through the Industry Foundation Classes (IFC) standard. An adopted analogy between DOSE and construction industry is employed to provide interpretation and implementation for DOSE interoperability. While interfacing IFC object model to solve DOSE interoperability questions, an extension model for the structural view of IFC is proposed and accepted by the International Alliance for Interoperability. The DOSE application for real‐world urban systems is beyond the scope of this paper and is presented in an accompanying paper work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
73.
为查明色达—松潘断块地热资源赋存状态及热源来源,以四川黑水县内3处温泉(热水塘、上达古、卡龙沟)为研究对象,采集温泉水样进行水化学分析和同位素测试,研究地热水的补给来源和热储温度。研究结果显示,热水塘温泉的地下水化学类型为HCO3-Na型,上达古温泉和卡龙沟温泉的地下水化学类型为HCO3-Ca型,补给水源主要为大气降水,补给高程分别为5 121 m、3 890 m、3 921 m。结合矿物饱和指数,采用SiO2地热温标计算3处温泉的热储温度,分别为119.036 ℃、49.034 ℃、30.215 ℃。综合分析认为研究区地下热水的成因主要为大气降水经高山补给区入渗至储集层,吸取地下深部向上传导的热量和放射性元素衰变释放的热量,并与围岩发生水-岩作用形成地下热水,在断裂发育部位热水沿断裂带向上运移,最后在地表出露形成温泉。  相似文献   
74.
Iron sulfide (FeS) was investigated using first-principles calculations up to a pressure of 400 GPa. A number of new phase transitions were found. An antiferromagnetic MnP-type structure, FeS II, was confirmed to be stable at low pressures, whereas at high pressures (40–135 GPa) we find a new stable phase, with a non-magnetic MnP-type structure, FeS VI. The observed first-order change in the cell shape between the two phases can be explained by the difference in magnetic configurations. The calculated cell parameters, atomic coordinates, and bulk modulus of non-magnetic MnP-type phase are consistent with those determined from experiment. The upper pressure limit of the stability of the non-magnetic MnP-type phase was calculated to be 135 GPa. A hitherto unsuspected phase transition from the non-magnetic MnP-type to a phase with Pmmn symmetry, FeS VII, was identified using the evolutionary crystal structure prediction (USPEX) method. The structure of the Pmmn phase has no known analogues, but can be described as a distortion of the NaCl-type structure. The Pmmn phase with the distorted NaCl-type structure is stable from 135 GPa at least up to 400 GPa. According to previous experiments and the present study, the transition sequence of FeS at low temperatures is as follows: troilite ➔ antiferromagnetic MnP-type phase ➔ monoclinic phase ➔ non-magnetic MnP-type phase ➔ Pmmn phase. The calculated volume reduction from the monoclinic to the non-magnetic MnP-type phase is 1.0% at 40 GPa, which is in good agreement with experimental observations. The calculated volume reduction from the non-magnetic MnP-type to the Pmmn phase is 3.7% at 135 GPa.  相似文献   
75.
Seasonal changes in oceanographic conditions related to primary productivity was investigated in the southwestern Okhotsk Sea during non-iced seasons, using the observation data conducted in 2000∼2006. Based on hydrographic characteristics, the studied area could be classified into two regions, the Coastal Region which is influenced under the Soya Warm Current and the Forerunner Water of the Soya Warm Current, and the Offshore Region where the Intermediate Cold Water was located in the subsurface layer. This study is the first report on seasonal change of nutrient and chlorophyll a concentrations in the offshore region of the southwestern Okhotsk Sea. Variability of concentrations of chlorophyll a and nutrients is temporally and regionally high in the Coastal Region. The maximum chlorophyll a concentration in April was observed at the surface layer of both regions. The most remarkable feature on the vertical structure in the Offshore Region was the consistent existence of the Intermediate Cold Water and the development of seasonal thermocline in the subsurface layer during summer and autumn. The stratification formed within the euphotic zone in the Offshore Region resulted in the formation of the subsurface chlorophyll a maximum (SCM) from May to October. Throughout the research period, although less amplitude of nutrients at the surface was observed in the Coastal Region than that in the Offshore Region, comparable amplitude of chlorophyll a concentration was observed between regions. These results suggested differences of environmental conditions for primary production between the two regions. Depending on the presence of SCM, relationships between chlorophyll a concentration at the sea surface and chlorophyll a standing stock within the euphotic layer were different. At most stations with SCM, the surface chlorophyll a concentration was lower than 0.6 mg m-3. This suggests that the presence of SCM and the chlorophyll a standing stock within the euphotic layer may be estimated using the surface chlorophyll a concentration from spring to autumn in the studied area.  相似文献   
76.
77.
通过岩石学、同位素年代学、变形变质特征的研究及区域对比,认为凤太泥盆纪盆地东缘(黄柏原一带)原划泥盆纪地层应为新太古代-古元古代变质结晶基底,变质达角闪岩相,其可能是佛坪穹隆构造向西北延伸,进一步证明了泥盆纪时西部凤太盆地和东部山(阳)柞(水)镇(安)盆地是两个独立盆地,中间被佛坪穹隆隔挡。该项成果对研究南秦岭地壳演化和指导凤太地区的地质找矿意义重大。  相似文献   
78.
Direct numerical simulations of an Ekman layer are performed to study flow evolution during the response of an initially neutral boundary layer to stable stratification. The Obukhov length, L, is varied among cases by imposing a range of stable buoyancy fluxes at the surface to mimic ground cooling. The imposition of constant surface buoyancy flux , i.e. constant-flux stability, leads to a buoyancy difference between the ground and background that tends to increase with time, unlike the constant-temperature stability case where a constant surface temperature is imposed. The initial collapse of turbulence in the surface layer owing to surface cooling that occurs over a time scale proportional to \(L/u_*\), where \(u_*\) is the friction velocity, is followed by turbulence recovery. The flow accelerates, and a “low-level jet” (LLJ) with inertial oscillations forms during the turbulence collapse. Turbulence statistics and budgets are examined to understand the recovery of turbulence. Vertical turbulence exchange, primarily by pressure transport, is found to initiate fluctuations in the surface layer and there is rebirth of turbulence through enhanced turbulence production as the LLJ shear increases. The turbulence recovery is not monotonic and exhibits temporal intermittency with several collapse/rebirth episodes. The boundary layer adjusts to an increase in the surface buoyancy flux by increased super-geostrophic velocity and surface stress such that the Obukhov length becomes similar among the cases and sufficiently large to allow fluctuations with sustained momentum and heat fluxes. The eventual state of fluctuations, achieved after about two inertial periods (\(ft \approx 4\pi \)), corresponds to global intermittency with turbulent patches in an otherwise quiescent background. Our simplified configuration is sufficient to identify turbulence collapse and rebirth, global and temporal intermittency, as well as formation of low-level jets, as in observations of the stratified atmospheric boundary layer.  相似文献   
79.
Residents of 401 mobile homes in Georgia, Mississippi, Illinois, and Oklahoma were surveyed after they heard a tornado warning. Most residents (69%) did not seek shelter during the warning. Half of those who sought shelter went to the frame house of a friend, neighbor, or relative, and 25% of those sought shelter in a basement or underground shelter. Some of the places where residents sought shelter were of dubious quality, such as their own mobile home, another mobile home, or in an out-building. Twenty-one percent of mobile home residents believed that they had a basement or underground shelter available as shelter during a tornado warning, and about half of those said they would drive to the shelter. Residents said they would drive if the shelter was more than 200 m away. Fifteen percent actually had a basement or underground shelter suitable as shelter within 200 m of their mobile home, but only 43% of the residents would use those shelters. The most common reason cited for not using the shelters was that they did not know the people who lived there. Likewise, a frame house or other sturdy building was within 200 m of 58% of the mobile homes, but only 35% of the residents stated they would use those houses for shelter. Thirty-one percent of mobile home residents had a ditch that was at least 0.5 m deep within 200 m of the mobile home. However, 44% of these ditches had utility lines overhead, 23% had water in them, and 20% had trees overhead. The limited tornado shelter options among mobile home residents in the United States needs to be incorporated into safety instructions so that residents without nearby shelter are allowed to drive to safer shelter.  相似文献   
80.
A rare, but normal, astronomical event occurred on November 9th 2006 (JST) as Mercury passed in front of the Sun from the perspective of the Earth. The abundance of the sodium vapor above the planet limb was observed by detecting an excess absorption in the solar sodium line D1 during this event. The observation was performed with a 10-m spectrograph of Czerny-Turnar system at Domeless Solar Tower Telescope at the Hida Observatory in Japan. The excess absorption was red-shifted by 10 pm relative to the solar line, and was measured at the dawnside (eastside) and duskside (westside) of Mercury. Between the dawn and dusksides, an asymmetry of total sodium abundance was clearly identified. At the dawnside, the total sodium column density was 6.1×1010 Na atoms/cm2, while it was 4.1×1010 Na atoms/cm2 at the duskside. The investigation of dawn-dusk asymmetry of the sodium exosphere of Mercury is a clue to understand the release mechanism of sodium from the surface rock. Our result suggests that a thermal desorption is a main source process for sodium vapor in the vicinity of Mercury.  相似文献   
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