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1.
An example of a complex geotechnical solution is cited for the construction of buildings housing the Business Center in Moscow, which includes the analysis, design, and construction of a trench enclosure for the building complex, including an architectural monument with an underground level, and a newly constructed building with from two to three underground levels, as well as the church of Saint Peter and Paul on Yauze, which abuts the buildings under construction.  相似文献   

2.
Results are presented for determination of the peak p, residual r, and standard f,st strengths of clayey soils containing up to 35% of particle inclusions ranging in size from 1 to 10 mm. It is established that on transition from p to r, the parameter C of Coulomb's law becomes essentially equal to zero, while the angle remains constant. A method is examined for repeated torsional testing of soil samples under conditions where shear strain s and torsional moments M tor are controlled to establish their strength.  相似文献   

3.
Observation of collapsed coiled (steel) furniture springs has been utilized for several decades or more by arson investigators as an indicator of whether an accelerant or smoldering source (such as a cigarette) caused a fire. This paper cites the contradictory literature, synopsizes metallurgical phenomena operative when coiled steel springs are subjected to fires, and presents empirical data from U.S. Federal Bureau of Investigation (FBI) Laboratory testing. It is concluded that observation of the collapsed state of coiled furniture/bedding springs is not a reliable indicator of whether a fire was initiated by a smoldering cigarette or accelerated by the presence of a hydrocarbon.  相似文献   

4.
Kurzfassung Die Wasserrahmenrichtlinie regelt den Schutz von Grund- und Oberflächengewässern und fordert eine nachhaltige Wassernutzung. Sie legt einen Zeitplan fest, um bis zum Jahr 2015 für alle Gewässer einen guten Zustand zu erreichen. Der erste Schritt ist eine Bestandsaufnahme der Gewässer. Für das Grundwasser besteht diese aus einer erstmaligen Beschreibung, einer weitergehenden Beschreibung und der Prüfung der Auswirkungen menschlicher Tätigkeit auf das Grundwasser. Die Wasserrahmenrichtlinie wird unabhängig von administrativen Grenzen innerhalb von hydrologischen Einzugsgebieten umgesetzt. Im deutschen Teil des Flusseinzugsgebietes der Elbe wurden 5 Koordinierungsräume gegründet. Der Koordinierungsraum Mulde-Elbe-Schwarze Elster (MES) wird vorgestellt. Beispielhaft für die angewandten Methoden wird die Beurteilung diffuser Stoffeinträge in das Grundwasser bei der erstmaligen Beschreibung erläutert. Die Ergebnisse der Bestandsaufnahme Grundwasser im Koordinierungsraum MES werden präsentiert. Von 54 Grundwasserkörpern ist für 25 Körper aufgrund der Belastungen durch Punktquellen und diffuse Quellen, wegen des mengenmäßigen Zustands oder sonstiger anthropogener Einwirkungen die Zielerreichung nach der Wasserrahmenrichtlinie unklar/unwahrscheinlich.
Status review groundwater for the Water Framework Directive in the coordination zone Mulde-Elbe-Schwarze Elster
Abstract The Water Framework Directive (WFD) governs the protection of groundwater and surface water and promotes sustainable water use. It sets up a timetable to ensure that a good status of all waters will be achieved by 2015. The first step is a status review of the waters. For groundwater, this procedure is divided into an initial characterisation, a further characterisation and a review of the impacts of human activity on groundwater. The WFD is to be implemented independently of administrative boundaries within hydrological river basins. In the German part of the Elbe river basin district five coordination zones have been established. The Mulde-Elbe-Schwarze Elster (MES) coordination zone is introduced. As an example for the applied methods, the assessment of the pressures of groundwater by diffuse sources (initial characterisation) will be explained. Then the outcome of the status review groundwater in the coordination zone MES will be presented: From the 54 individual bodies of groundwater 25 bodies will probably not achieve the environmental objectives of the WFD because of the pressures point sources, diffuse sources, quantitative status or other anthropogenic impacts.
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5.
A common dilemma in economic development planning is that the achievement of one objective often constrains the achievement of another, resulting in a range of options or tradeoffs among alternatives. This paper examines pairs of economic objectives for a multicounty planning region (e.g., maximize balance-of-trade surplus, maximize local employment) and derives tradeoff curves which might prove useful to planners. Several objectives examined might be considered as capital-oriented (e.g., maximize trade surplus). These objectives yield regional economic outcomes more similar to each other than to outcomes from labor-oriented objectives (e.g., maximize local employment). The range of the tradeoff curve is much greater for pairs of objectives between than within these two groups. The range and curvature of the tradeoff curves tend to increase as the level of the curve shifts outward due to a relaxation of the constraints for exports and incommuting labor. This suggests that conflicts may increase as regions become more open to trade and commuting; the need for compromise among differing local interests increases accordingly.  相似文献   

6.
Present firesafety measures were conceived to deal with hypothetical fires spreading by destruction of successive compartment boundaries. A new firesafety system, referred to as the fire drainage system, is designed to cope with real-world fires spreading mainly by convection. It confines fire and smoke to the room of origin and to a small corridor element adjacent to the room. The system can be designed to operate without the use of water and electric energy. The fundamentals of its design are described and some experimental information is presented. Reference: T. Z. Harmathy and I. Oleszkiewicz, Fire Drainage System,Fire Technology, Vol. 23, No. 1, February 1987, p. 26.This paper is a contribution from the Institute for Research in Construction, National Research Council of Canada.  相似文献   

7.
This note applies an input-output multiplier technique developed by Burford and Katz to analyzing the impact of potential high technology industries in a rural, four-state, thirteen county Midwestern region. By using the 1972 national input-output table coefficients and the Burford-Katz multiplier estimation formula, the estimated output impacts for fifty-one individual industries were calculated. The results indicate that within the four-state region, conventional industries would produce greater economic impacts than designated high-tech ones. This analysis could be performed rather easily for any other region in the U.S.  相似文献   

8.
The purpose of this paper is to clarify the economic determination of the regional labor supply. In explaining the regional level of labor force participation two models are compared: the unemployment model based on the discouraged worker hypothesis and the neoclassical model of labor force participation. It is shown that a migration model complements the neoclassical model and provides an alternative interpretation of the discouraged worker hypothesis, this reinterpretation provides an explanation for the failure of the unemployment model at the regional level when it is quite successful at the national level.  相似文献   

9.
This paper assesses the impact of the production and use of an intermediate good upon the location of productive activity in an economy consisting of two asymmetrically sized regions. The Nash equilibria of locations of an upstream and two downstream firms are completely defined in the the space of parameters transport cost and intensity of vertical linkages. While the relationship between transport cost and agglomeration is usually regarded as a decreasing one, the inclusion of an intermediate good can make it nonmonotonic.Received: September 2003/Accepted:01 March 2004The author wishes to thank the Editor of The Annals of Regional Science and three anonymous referees for helpful comments. The usual disclaimer applies.  相似文献   

10.
This paper extends the Leontief dynamic input-output model by incorporating continuous lags, capacity constraints, excess capacity and limits on disinvestment in each sector. These extensions result in phase changes, where sectors discretely change from one set of conditions to another. The resulting system of equations is solved by numerical methods and applied to the U.S. economy. Projections for the 1952 to 1962 period are compared with actual levels.  相似文献   

11.
Full scale fire tests have been carried out in order to study the influence of different ventilating principles on the time point of fire detection and the smoke filling of a four-bed room. Using conventional mechanical ventilating systems as smoke exhaust systems the time difference left for evacuation of the fire room can be positively influenced. With the conventional ventilating system operating there is a significant difference between time points of detection of the ionization and optical smoke detectors, for both flaming and smoldering fire. Using the low momentum displacement ventilation this difference is reduced, resulting in possibilities for the ionization smoke detector to be optimized for both flaming and smoldering fires. Reference: Øystein Meland and Eimund Skåret, Smoke Control in Hospitals,Fire Technology, Vol. 22, No. 1, February 1986, p. 33.  相似文献   

12.
The effect of loading and unloading regimes on the threshold of the appearance and number of cracks, which precede their avalanche propagation that accompanies complete failure of the soil, is established. It is demonstrated that the appearance of pioneer cracks contributes to an increase in ultimate deformations of the soil, corresponding to its failure and energy consumption of the deformation process.  相似文献   

13.
Questions concerning the similitude of seismic oscillations during an electric discharge in a hole and the detonation of explosives are examined; data are presented for field measurements; the parameters of oscillations generated during an electric discharge are compared with those based on existing standards for seismic-blast effects, and also with results obtained by a number of researchers. Selection of the characteristics of an electric blast to ensure seismic safety of the procedure under consideration is substantiated.privately owned joint-stock Company RITA  相似文献   

14.
A procedure for, and results of experimental investigations performed to substantiate the effectiveness of the method of infrared (IR) radiation in diagnosing changes in the stress state of soils over time are presented. The construction of a large-scale bench is described for the alternating loading of a relatively large (of the order of 0.35 m3) volume of soil. Variations in the stress state over time in the near-face zone of a borehole, which is arranged in a model of the soil mass, are recorded using synchronous recordings of signals from an IR radiometer and load-cell strain gages. The elastic nature of stress variations on the face of the borehole in an unsaturated sandy soil is revealed during alternating-sign stress variations at infinity. It is indicated that data derived from noncontact IR measurements will make it possible to record accurately moments of jumpwise stress variations in the soil mass, and evaluate their intensity.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 8–11, November–December, 2004.  相似文献   

15.
On knowledge networks in science: collaboration among equals   总被引:3,自引:0,他引:3  
Knowledge is produced from labor and existing knowledge as embodied in documents and persons. Through knowledge networks, researchers can utilize knowledge inputs from other scientists. This paper examines institutions for knowledge exchange and attempts a formal analysis of scientific exchange in passive and active collaboration.I am indebted to Professors Tawada, Sakai, Ohta and John Roy for helpful comments and corrections.This paper was presented in draft form at an International Workshop on Trade, Knowledge and the Network Economy, held in December 1992 in Mallacoota, Australia.  相似文献   

16.
Conclusions 1. The construction of compacted soil beds makes it possible to eliminate the collapsibility properties of soils in the bases of buildings and structures to a depth of 8–12 m. The dry density of the soil in the compacted soil mass was 1.73–1.80 tons/m3.2. In the upper part of the soil bed, to a depth of 1.0-1-3 m a decompressed soil layer with d=1.35–1.55 tons/m3 is formed, which must be additionally compacted with heavy rammers.3. The moduli of deformation of the soils at the tamped soil bed in the pressure range 0–4 MPa are 18–21 MPa.4. To prevent bulging out at the soil to the surface, tamping of the material at the face and filling of the trench hollow must be carried out to a "refusal" equal to 10 cm per blow.5. Use of tamped soil beds is recommended for buildings with on equivalent pressure equal to or exceeding 0.1 MPa in collapsible soils with 1.6d1.4 tons/m3 and in fill soils with d1.6 tons/m3. The corresponding natural water content of the soil should be in the range wp+0.04wwp–0.04.VNIIOSP Institute. "Orgatroi" Trust of the Ministry of Construction of the Moldavian SSR. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 7–9, May–June, 1988.  相似文献   

17.
TheChicago Area Transportation/Land-Use Analysis System (CATLAS) is a large scale urban simulation model which synthesizes location rent analysis from urban economics with travel demand analysis from transportation planning. This paper describes the theoretical formulation, empirical estimation and policy application of CATLAS to the evaluation of CBD-oriented rapid transit projects in Chicago.  相似文献   

18.
This paper compares the output multipliers of the 1967 National input output model (367 industries) with the multipliers of the aggregated version (81 industries). The results show that, generally, the set of industries in the full model that were aggregated together for the reduced model, display a wide range of output multiplier values. Therefore, the output multiplier of an aggregated industry may not be truly representative of any of the industries that were joined together. Finally we show how information for a particular firm or disaggregated industry can be incorporated in an aggregated input-output model to obtain a close estimate of the actual output multiplier for that firm or industry.  相似文献   

19.
A procedure is proposed for the computational modeling of the driving of a deep tunnel by a tunnel-boring machine (TBM) with an active surcharge on the face, which is realized in the GEO-MIGG program. Basic factors affecting the stress-strain state (SSS) of the soil bed-TBM- buildings and structures of the urban setting system are demonstrated in a trial example. The feasibility of using the proposed procedure is confirmed by comparing results of computational modeling of a practical example of tunneling for the third transportation beltway around Moscow in the area of Lefortovo using a TBM manufactured by the German firm Herrenknecht with data derived from field observations.  相似文献   

20.
Conclusions 1. The failure of a sandy foundation bed under a rigid embedded reinforced-concrete foundation (h/b0.5) with a flat, rough lower surface is three-dimensional in nature when the loads are inclined at =20–40° to the vertical.2. Plane shear is not observed when the load is inclined at an angle = and the eccentricity e0 ( is the angle of the soil's internal friction as determined on a shear apparatus in accordance with GOST 12248–66).3. The settlements and lateral displacements of an embedded foundation (h/b>0.5) in the limiting state are 2–3 times larger than those of the nonembedded foundation; lateral displacements exceed the limiting values established for farm buildings [2], or approach them.4. For angles =20–40°, eccentricity of the inclined load in the direction opposite to the horizontal component, but not less than rC (rC is the core radius of the section) effects an increase in the ultimate load as compared to a central positioning of the resultant. Additional experiments and theoretical studies are required to investigate the role of positive and negative eccentricity on the bearing capacity of the foundation bed.5. For loads inclined at angles =35–40° and a relative foundation embedment 0.5h/b1, computation in accordance with SNiP II-15-74 yields considerably lower bearing capacity than computation from experimental data.6. The studies that we conducted are used to develop a more economical method of computing and designing foundations for farm buildings under an inclined loading, which is employed in practice [2].B. E. Vedeneev All-Union Scientific-Research Institute of Hydraulic Engineering. Central Scientific-Research Institute of Experimental Design and Planning for Rural Construction. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 3–6, July–August, 1979.  相似文献   

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