Engineering geological and geophysical investigations of a slope failure at Edinburgh Castle, Scotland

Edinburgh Castle is one of Scotlands most important heritage sites. It was built on a classic crag and tail structure where the crag consists of columnar jointed basalt and the tail of sediments protected from glacial erosion by the crag.In 1997 apparent instability was observed on the southern side of the tail. A shallow slope failure was proved to have taken place within saturated, layered, cohesive to non-cohesive, loose to dense heterogeneous fill on a slope of 44°. The date of the initial failure is not known, but is likely to have taken place over a period of many years, since at least the 1950s.Remediation works were subsequently undertaken to stabilise the slope, consisting mainly of the installation of soil nails, a bi-axial geo-grid and minor filling to mitigate the effects of the ground movements and to facilitate repair of the retaining wall.     

Running hot and cold in the urban home-ownership market: The experience of Japan’s major cities

Urban home-ownership in Japan was destabilised when the bubble economy collapsed at the beginning of the 1990s. This paper looks beyond the social and economic changes in Japanese housing in the post-bubble recession to focus on the ups and downs in current home-ownership markets in Japans major cities. Since the mid-1990s, social fragmentation has created a novel environment for urban home-ownership. The combination of a prolonged recession and a policy to promote housing construction and urban redevelopment has split urban space into hot spots, where the housing market is increasingly active, and cold spots, where the market is persistently inactive.     

Impact of spatially separated work places on urban residential location,consumption and time allocation

This paper analyses the impact of informatics development on the urban residential-location, consumption and working-hour-allocation behaviour of the coming information-oriented society. The analysis focuses on the repercussions through the interaction of the land and labour markets. The labour market is spatially separated into the home work market in the city suburbs and the office work market in the CBD. But, these work places are tightly connected with each other by highly developed communication technology. The time-allocation as well as money-expenditure constraint is systematically built up on a traditional residential location model of the von Thunen-Alonso type. The wage rates and the bid rent function for the land are both solutions of the equilibrium model of land and labour markets. The impacts are examined using the comparative statics analyses which have been developed for the economic-agent equilibrium conditions of the firm and household.     

Alternative approaches to the estimation of economic impacts resulting from supply constraints: Comment and elaboration

Davis and Salkin previously derived impact equations for supply constraints in terms of partitioned direct coefficients matrices under alternative assumptions. This paper derives equivalent equations under both assumptions but in terms of partitioned inverses. Impacts of supply constraints then may be interpreted by means of corresponding gross output multipliers, and in terms of the total (direct and indirect) effects of the supply constraints.Formerly Senior Economist, Federal Emergency Management Agency.     

Methods to calculate the response time of heat and smoke detectors installed below large unobstructed ceilings

Recently developed methods to calculate the time required for ceiling mounted heat and smoke detectors to respond to growing fires are reviewed. A computer program that calculates activation times for both fixed temperature and rate of rise heat detectors in response to fires that increase in heat release rate proportionally with the square of time from ignition is given. This program produces nearly equivalent results to the tables published in Appendix C, Guide for Automatic Fire Detector Spacing (NFPA 72E, 1984). A separate method and corresponding program are provided to calculate response time for fires having arbitrary heat release rate histories. This method is based on quasi-steady ceiling layer gas flow assumptions. Assuming a constant proportionality between smoke and heat released from burning materials, a method is described to calculate smoke detector response time, modeling the smoke detector as a low temperature heat detector in either of the two response time models.Nomenclature A g/(c _p T ) - c _p specific heat capacity of ambient air - C _s smoke mass concentration - D effective binary diffusion coefficient - g acceleration of gravity - H vertical distance from fuel to ceiling - I light intensity - I_o initial light intensity - L light beam length - _s smoke gas mass production rate per unit volume - OD optical density per unit length (see Equation 8) - fire energy release rate - energy release rate per unit volume - r radial distance from fire axis to the detector - RTI response time index, the product of the detector thermal time constant and the square root of the gas speed used in the test to measure the time constant.⁹ - t time - t ₂ ^* dimensionless time t/[A^{–1/5 –1/5} H^4/5) - (t ₂ ^* ) _f dimensionless time for time delay for gas front travel - T ambient temperature - T gas temperature at detector location - T _s temperature of detector sensing elements - T T — T - T ₂ ^* dimensionless temperature differences T/[A^2/5(T _f /g) ^2/5 H^–3/5] - U gas speed at the detector location - U ₂ ^* dimensionless gas speed U/[A H]^1/5 - Y _s local ratio of smoke mass to total mass in flow - proportionality constant for t²-fire growth = Q/t² - ambient air density Reference: David D. Evans and David W. Stroup, Methods to Calculate the Response Time of Heat and Smoke Detectors Installed Below Large Unobstructed Ceilings,Fire Technology, Vol. 22, No. 1, February 1985, p. 54. Note: This paper is a contribution of the National Bureau of Standards and is not subject to copyright.     

Urban unemployment and labor force participation in Korea

This paper examines urban unemployment patterns in Korea using a simultaneous model of unemployment and labor force participation. Urban demographic characteristics and economic conditions are put forward to explain inter-urban variations in the rates of unemployment and labor force participation. The estimation results indicate the importance of local demographic characteristics and economic conditions in determining labor force participation rates and unemployment rates. The results clearly indicate that sexual dualism is pervasive in the urban labor market in Korea. Market discrimination against women is quite evident. The effect of city size seems to be insignificant except that large cities tend to provide a more favorable environment for women to participate in the labor force.     

How alcohol-related crashes of different severity interrelate and respond to local spatial characteristics:An evaluation of a common site sales ban on alcohol and gasoline

Highway safety is an important issue in both urban and rural areas. Based upon a unique panel of incorporated cities over a 96-month period from January 1982 to December 1989, this paper evaluates the effects of the State of Californias ban on common site sales of gasoline and alcohol to curb drunk driving. Geographic information systems (GIS) contribute spatial variables to an analysis of the impact of the ban on several categories of alcohol related crashes: fatalities, serious injuries, and property damage. By considering the types of alcohol-related crashes for the five-county Los Angeles area as interrelated, a seemingly unrelated regression (SUR) model locates more precise impacts. Overall the ban appears to reduce fatalities, serious injuries, and property damage crashes; but in relatively less population dense cities, the ban increases property damage and may increase more serious crashes in some urban neighborhoods. This suggests that the ban discourages highly impaired drivers but may motivate less impaired drivers to travel to an alternate alcohol purchase site. Diverse experiences in adjacent municipalities warn large regional or nation-wide evaluations of highway safety to take care when adopting large region or state fixed effect adjusters in analyses that presume sub-region homogeneity.Received: October 2003/Accepted: February 2004All correspondence to: Clifford A. Lipscomb. The authors would like to express their appreciation to Subrahmanyam Muthukumar for his assistance in preparing the GIS spatial variables. The views expressed in this paper are solely the authors and do not necessarily reflect the views of either the Bureau of Economic Analysis or the U.S. Department of Commerce.     

Postflashover fires — an overview of the research at the national research council of Canada (NRCC), 1970–1985

The NRCC model of fully developed compartment fires is discussed. Although the mathematics involved is quite simple, it allows a rather comprehensive simulation of the fire process. The model offers an explanation for the findings that ventilation control is related to the pyrolysis mechanism and is not a result of scarcity of air in the fire compartment, and that thermal feedback is of secondary importance in the burning (pyrolysis) of cellulosic fuels. Another feature of the model is the introduction of the normalized heat load concept. The normalized heat load is a scalar quantity that depends on the total heat absorbed by the compartment boundaries during the fire incident, and is practically independent of the temperature history of the fire. A simple explicit formula has been proposed and proved experimentally to describe the normalized heat load for real-world fires with fair accuracy. The normalized heat load concept offers a simple means for converting fire severities into fire resistance requirements, and makes it possible to design buildings for prescribed levels of structural fire safety. The potential of fires to spread by convection and the expected characteristics of fires of noncharring plastics are also discussed. Reference: T. Z. Harmathy, Postflashover Fires—An Overview of the Research at the National Research Council of Canada (NRCC), 1970–1985,Fire Technology, Vol. 22, No. 3, August 1986, p. 210.     

A continuous Leontief dynamic input-output model

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.     

The use of compressed natural gas (CNG) in motor vehicles and its effect on employment and air quality

This study measures industrial output, employment and air pollution effects through the use of CNG in motor vehicles by utilizing the Pollution-Related Multiregional Household-Interactive Variable Input-Output (PHVIO) model. The impact analyses are conducted with three consecutive year scenarios of different level of CNG conversion of motor fleet vehicles for the target year, 1991, 1992, and 1993. The use of CNG in bus and truck vehicles of private businesses, consumers, and state and local governments produces the substitution effect and income effect. The use of CNG reduces the costs of transportation, and the output, employment and air pollution effects of the reduced transportation costs are referred as the substitution effect. The use of CNG increases natural gas consumption and requires CNG duel engine installation while it decrease gasoline consumption. The output, employment and air pollution effects of this final demand change are referred to the income effect. The industrial output and employment effects are measured in Oklahoma and the Rest of the U.S. Then Oklahoma State industrial and employment effects are divided into Oklahoma SMSA, Tulsa SMSA and the Rest of Oklakoma. Finally, the stationary source air pollution due to industrial effects and mobiles source air pollution due to CNG using motor vehicles are measured in Oklahoma SMSA and Tulsa SMSA.     

Social housing in Latin America: Opportunities for affordability in a region of housing need

In advanced capitalistcountries, the term social housing normallyrefers to social rented housing, and itsprovision can be examined within the context ofthe type of housing welfare regime that hasevolved within the country under consideration.However, in large parts of Latin America –because of minimal affordability and limitedinvestment – social housing is very much amarginalised tenure and – apart from a smallsocial-rented sector – comprises illegalshelter in shantytowns, assisted self-buildhousing, and low-cost owner-occupation. Itwould therefore be unproductive to examinesocial housing in Latin America within thecontext of any of the welfare regimes thatprevail in the developed world.Within the region, large-scale migration intothe major urban areas created a substantial andgrowing housing deficit among the poor in thelatter half of the twentieth century. At first,there was an attempt to satisfy housing needsby the provision of social rented housing, butit was soon recognised that such accommodationwas unaffordable to the majority of the poor,while municipal governments were constrained bybudgetary considerations from increasing oreven maintaining its supply. At the same time,it was realised that informal housing could beupgraded more cost-effectively, and that forits future development the legalisation oftenure was essential; while self-build formalhousing could be constructed through theprocess of community funding. By the 1990s,even the middle-income segment wasdisadvantaged in the housing market asunemployment and interest rates rose and realwages fell, and therefore – through theintroduction of means-tested demand-sidesubsidies – the term social housing wasextended to the conventional owner-occupiedsector.Clearly, welfare regimes in Latin America areat a rudimentary stage in their development,although there is a tendency for governments toembrace neo-liberal housing policies. But at atime of fiscal constraint, it is a cause forconcern that macroeconomic priorities mightmake it more difficult for a large proportionof the population of the region to satisfy itshousing needs.     

Smoke Control in Hospitals

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.     

Estimation of environmental impacts on the water quality of Incesu-Dokuzpınar Springs in Kayseri,Turkey

Industrial and agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO₃, N₂, Cl, SO₄, H⁺, K, Mg, Ca, Fe, Cu, B, Pb and Zn, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO₃, it is recommended that a combination of hydrochemical and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. The water type of ncesu-Dokuzpnar Springs is mainly Na–Mg–Ca–Cl–HCO₃. Note that the water types of the Springs were directly related to the hydrogeochemical properties of outcrops at the study area. Thus, the high concentration of Ca⁺² and HCO₃ is mainly related to the high CO₂ contents in the marbles, whereas the high Na concentration arises from the existing syenite, volcanic ash, basalt and clay units, although the ncesu-Dokuzpnar Springs cover most of the drinking and irrigation water demands at the study area. Therefore, relevant hydrogeochemical and statistical studies were carried out for estimating the mentioned environmental impacts on the water quality of ncesu-Dokuzpnar Springs.     

Changing modes of reasoning in spatial choice analysis

In the development of regional science methodology we observe an increasing series of trends from aggregate towards disaggregate, deterministic towards probabilistic and static towards dynamic modes of reasoning. This paper attempts to discuss some major aspects of these types of transition in the field of spatial choice analysis where particular emphasis is laid on issues which have been addressed in papers presented in the sessions on Recent Methodological Developments in Spatial Analysis.     

Feasibility of Face Surcharging during Deep Settlement-Free Tunneling in Dense Urban Settings

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.     

Factors affecting the greater damage in the Avcılar area of Istanbul during the 17 August 1999 Izmit earthquake

The 17 August 1999 earthquake at zmit, Turkey was triggered by the North Anatolian Fault Zone. It resulted in widespread damage, particularly in Avclar, in the European part of Istanbul and some 100 km from the epicentre. This paper reviews the geomorphology, geology, foundations and structures in the Avclar area, in order to assess the main reasons for the extensive collapse of buildings. It is considered that the basinal structure of the area, the varying thicknesses of bedrock and the presence of secondary tear faults were important contributory factors. In addition, the poor quality of the construction meant the buildings were unable to accommodate ground motions.     

Strength of Clayey Soils Subject to Large Shear Strains

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.     

Dynamic forecasting of travel demand,residential location and land development

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.     

Dispersed spatial input demand functions

Most recent attempts to improve the empirical performance of classical trade models by formulation of probabilistic models of the DSPE (Dispersed Spatial Price Equilibrium) type have concentrated on determination of flows of a single commodity. However, a further challenge is to develop consistent probabilistic multi-sector spatial input demand functions and the corresponding spatial supply functions as part of an eventual probabilistic spatial CGE (Computable General Equilibrium) framework. In this paper, we derive short-run aggregate spatial input demand functions as the generators of the spatial supply functions, introducing via entropy some distributional assumptions about the average behaviour of the representative firm. In order to remain compatible with entropy principles, all demand functions are derived in a form guaranteeing compliance with a probabilistic accounting framework, calibrated on observed quantities, costs and prices. Firstly, the paper develops dispersed spatial input demand functions using various classical production functions, such as Linear and CES, accounting for the transport costs and tariffs incurred by the supply of intermediate inputs. It then formulates dispersed interregional input demand functions based on multiregional input-output production functions, transcending the normal relations connecting input and output via constant coefficients, with solution via a price-sensitive iterative adjustment technique. Finally, guidelines for an extension to a long-run analysis are sketched.