THE CAUSAL RELATIONSHIP BETWEEN EMPLOYMENT AND BUSINESS NETWORKS IN U.S. CITIES

ABSTRACT: Scholars from a range of disciplines have long recognized that a city's economic fortunes are closely tied to its position in networks of interurban exchanges. However, it remains unclear whether cities occupy a central position in the network because they are sites of significant economic activity (i.e., a flow generation hypothesis), or whether they experience greater economic growth because they occupy a central position in the network (i.e., a structural advantage hypothesis). This article tests these complementary hypotheses by examining the total nonfarm employment in, and air travel patterns of business passengers among, 128 U.S. metropolitan areas from 1993 to 2008 using a series of lagged regression models. Results lend support to the structural advantage hypothesis, but not for the flow generation hypothesis: centrality drives employment, but not vice versa. The article concludes with a discussion of the implications of these results for infrastructure‐focused approaches to economic development.     

Globalization and construction industry development: research opportunities

Raftery, J., Pasadilla, B., Chiang, Y. H., Hui, E. C. M. and Tang, B. S. (1998) Construction Management and Economics, 16, 729–37 review recent developments in the construction industries in Asia. They discuss the main causes and effects of key trends in globalization and their impact on the industries. This paper considers some of the points raised by Raftery et al. It starts with an overall review of their paper. It then considers construction industry development in general, technology transfer and joint ventures, and the impact of policy reform on the industries. It suggests additional relevant issues, and highlights some areas where further research would be appropriate.     

Homo Economicus in a Big Society: Understanding Middle-class Activism and NIMBYism towards New Housing Developments

Abstract

Problems of housing supply and affordability in England have long been recognized by policy-makers. A key barrier to supply is seen to be community activism by so-called not-in-my-back-yard activists (NIMBYs). The localism policy agenda, or devolving decision-making down to the local level, is central to how the UK coalition government seek to overcome this opposition. This conceives NIMBYism as a demonstration of homo economicus – of the rationality of economic beings seeking to maximize their utility. In this view, residents would not accept large urban extensions in suburban areas because they took on localized costs with no obvious benefits, unless incentivised appropriately. In this paper, we use analysis of British Social Attitudes Survey data as well as the results of the first review of middle-class activism in relation to public services to identify the likelihood of residents being incentivized by this version of localism to accept new housing. We conclude that the evidence on the individual and collective attitudes suggests that it is unlikely that localism will deliver new housing. Importantly, the political power of affluent and professional groups means they can ensure that their opposition is heard, particularly in the neighbourhood plans delivered through localism. The paper argues that planning for housing needs to understand communities as homo democraticus – as actively engaged in negotiating between complex interests with respect to support for new housing.     

Strategies for In Situ Home Improvement in Romanian Large Housing Estates

Socio-economic and physical change have visibly affected post-socialist cities, yet the state of decay of their inherited large housing estates has only deepened throughout the 1990s, despite the change in tenure through policies of large-scale privatisation. Housing disrepair has now reached a critical stage that requires rapid private and public intervention. This paper examines the extent to which Romanian block residents have been able to improve in situ their housing conditions since 2000, the strategies they employed and the challenges they faced. It focuses on the often ignored private domain of housing, flats and blocks, where changes are also likely to be less visible. By analysing the process of individual utility metering and the practice of collective block management, I argue that besides economics, the unregulated housing context and a relaxed legal culture have challenged individual and collective action and have generated a framework of housing privatism.     

Life cycle costing—Theory, information acquisition and application

Especially in the last two decades of an increasingly-competitive business environment, dwindling resources and an ever-increasing need to obtain value for money in all areas of corporate activity, it has become essential that all available resources be used optimally (Griffith, J. W. and Keely, B. J., Cost Engineering, 1978, September/October, 165–168). Physical assets form the basic infrastructure of all businesses and their effective management is essential to overall success. It has thus become essential to plan and monitor assets throughout their entire life cycle, from the development/procurement stage through to eventual disposal. Life cycle costing^∗ is concerned with optimising value for money in the ownership of physical assets by taking into consideration all the cost factors relating to the asset during its operational life. Optimising the trade-off between those cost factors will give the minimum life cycle cost of the asset. This process involves estimation of costs on a whole life basis before making a choice to purchase an asset from the various alternatives available. Life cycle cost of an asset can, very often, be many times the initial purchase or investment cost (Hart, J. M. S., Tetrotechnology Handbook, p. 22, HMSO, London, 1978; Hysom, J. L., Journal of Property Management, 1979, 44, 332–337). It is important that management should realise the source and magnitude of lifetime costs so that effective action can subsequently be taken to control them. This approach to decision making encourages a long-term outlook to the investment decision-making process rather than attempting to save money in the short term by buying assets simply with lower initial acquisition cost. It is suggested project managers should familiarise themselves with what the approach involves, to better appreciate how they might then contribute to the enhanced quality decision making which it makes possible.     

CME Forum: a response to “Construction flow index: a metric of production flow quality in construction”

The study of types of flow in construction is a relatively new field. This paper reviews the work of Sacks et al. and reveals that they have applied a production-line metaphor with recognition of two production flows. Process flow: locations are equated with products moving down a production line. Operations flow: work crews are equated to work stations. Their work proposes an index of the quality of production flow in construction, but the research design has three significant flaws: the skilled interpretation of flow-line charts is not in turn applied to the interpretation of their example charts; the conceptual framework does recognize that the underlying metaphor requires levels of detail in both location and task that is not supported in their analysis. The meaning of “quality of flow” in this context is not defined. This debate raises important epistemological questions for those working in lean construction and location-based management. While the concept of “production flow quality” is important, the Sacks et al. methodology does not address the detailed planning of individual crews. It is only possible to apply the production-line metaphor if micro-management is adopted as detailed planning.     

A general correlation to predict axial dispersion coefficients in aerated channel reactors

Tracer studies have been widely applied to characterize the flow behavior in activated sludge reactors. The channel reactor with bottom aerators is one of the widespread designs in large wastewater treatment plants. Its flow behavior is well modeled either as a plug flow reactor with axial dispersion or as the perfect mixing cells in series. Several correlations have been developed to estimate the dispersion coefficients as a function of operating and geometrical parameters. These correlations fit properly the data derived from a given reactor in the range of operating and geometrical parameters for which they have been determined. Unfortunately they cannot be applied straightforwardly with a sufficient level of confidence to scale-up industrial units or scale-down laboratory pilots. Recently, two papers have proposed more general correlations [Makinia, J., Wells, S.A., 2005. Evaluation of empirical formulae for estimation of the longitudinal dispersion in activated sludge reactors. Water Res. 39, 1533-1542; Potier, O., Leclerc, J.-P., Pons, M.-N., 2005. Influence of geometrical and operating parameters on the axial dispersion in an aerated channel reactor. Water Res. 39, 4454-4462] but they are still not able to represent the whole set of data from the literature. This paper proposes a general correlation, which can represent all the available and usable sets of data from the literature and more than 170 experimental results obtained in our laboratory with a precision of 18%.     

Around Madrid: the continuing influence of historical urban development plans on today’s periphery

This paper describes the peripheral development that has occurred in Madrid over the last 16 years (2000–2016), a period split by the economic crash that occurred in 2008. The paper argues that the relationship between economic development and infrastructure corridors witnessed in this peripheral development is intrinsically connected to the nineteenth and twentieth-century plans for urban growth. While these corridors have some similarities to the Strip model for an automobile city discussed by Robert Venturi and Denise Scott-Brown in their seminal book Learning from Las Vegas, the Madrid peripheries enjoy a long genealogy that complicates any easy link to the Strip, particularly around issues of economic speculation, typology and image-making or imagining, which will be introduced using the work of Michael Neuman and others. The research design adopted examines the treatment of the periphery in a number of historical plans, particularly their attitudes towards infrastructure and economic development, in order to establish connections between those historical plans and the city’s planned and (partially) realized peripheral development today.     

Key factors determining the energy rating of existing English houses

In the UK, the Standard Assessment Procedure (SAP) is used to rate the energy performance of existing dwellings whenever they are let or sold. This study investigates which of the inputs to SAP account for the most variance in energy rating across existing gas central heated houses in England. Data from the English Housing Survey (EHS) 2009 are used to generate a representative set of dwellings and variance-based global sensitivity analysis is then applied to assess each input's contribution to the variance in the calculated ratings. It is demonstrated that heating system efficiency, external wall U-value and dwelling geometry account for 75% of the variance of the energy rating of gas central heated houses in England. This suggests that improving heating system efficiencies and wall U-values of the worst performing dwellings will go a long way towards improving their energy rating and potentially reducing their energy consumption. It is also demonstrated that dwelling geometry has a much bigger influence on the calculated carbon emissions (accounting for 80% of the variance) than it does on the SAP energy rating (accounting for 30%), meaning that significant improvements in energy rating might not be accompanied by significant reductions in carbon emissions.     

Practices,barriers and benefits of risk management process in building services costs estimation: comment

This note is a comment on Mok, C.K., Rao Tummala, V.M. and Leung, H.M. (1997) Practices, barriers and benefits of risk management process in building services cost estimation, Construction Management and Economics, 15 (2), 161–75, which describes research into the risk perceptions and risk management practices of building services engineers in Hong Kong. The note questions statements made in the paper and parts of the research design and data analyses.     

The rise and decline of the New South Wales cooperative housing societies

Abstract

In the past, New South Wales cooperative housing societies made an important contribution to the financing of housing construction. In this paper the expansion and later contraction of the societies is explained. It is shown that, in recent times, not only have they suffered from a drying up of loan funding, but also a great number have operated at far below their possible level of efficiency.     

Azolla as a source of biomass: a comparison with water hyacinth

Aquatic weeds are known for their high growth potential. In this paper Azolla‐an aquatic free floating fern‐has been considered as a source of biomass. The five aspects, viz., habitat and distribution, habit and morphology, major chemical components, control measures and environmental influences, and utilization aspects have been focused and compared with those of the water hyacinth. The many advantages offered by Azolla over water hyacinth have been demonstrated. The possibility of using Azolla for biogas generation has also been emphasized.     

An ontology-based approach to support decision-making for the design of ETO (Engineer-To-Order) products

Most of the facility projects have Engineer-To-Order (ETO) products. One of the major problems associated with ETO products is their long lead-time. Previous studies show that the long lead-time has more than half of its causes associated directly or indirectly with the design phase, in which many project participants are involved. This paper explores approaches to better support the ETO product design process by improving information sharing among project participants and collaborating information systems.This paper proposes to use ontology as a technical solution to integrate heterogeneous systems. Subsequently, an ontological framework of electrical products for supporting decision-making is developed. The ontology supports the generation, analysis, sharing and reuse of domain knowledge as required by ETO business processes, thus providing information to support many information intensive business processes such as the evaluation of design alternatives. This paper also presents a case study, i.e., the selection of transformers, to demonstrate the use of the ontology. In addition, limitations of the study have also been discussed.     

En-gendering Effective Planning: Spatial Mismatch,Low-Income Women,and Transportation Policy

Welfare-to-work transportation programs are predicated on a conceptualization of the spatial mismatch hypothesis that focuses on the central-city residential locations of welfare participants, rapidly expanding job opportunities in the suburbs, and the long commutes needed to connect them. Feminist scholarship and travel behavior research, however, show that the travel patterns of low-income single mothers are not consistent with this behavior, resulting in a policy mismatch between many welfare recipients and their transportation needs. The research reviewed in this article indicates that policymakers and planners should do more to address the transportation needs of these low-income women. Policies must account for the important role of gender in determining where welfare recipients will look for work, how they are likely to conduct their job searches, and the mode by which they travel to both employment and household-supporting destinations.     

An ontology-based approach to support decision-making for the design of ETO (Engineer-To-Order) products

Most of the facility projects have Engineer-To-Order (ETO) products. One of the major problems associated with ETO products is their long lead-time. Previous studies show that the long lead-time has more than half of its causes associated directly or indirectly with the design phase, in which many project participants are involved. This paper explores approaches to better support the ETO product design process by improving information sharing among project participants and collaborating information systems.

This paper proposes to use ontology as a technical solution to integrate heterogeneous systems. Subsequently, an ontological framework of electrical products for supporting decision-making is developed. The ontology supports the generation, analysis, sharing and reuse of domain knowledge as required by ETO business processes, thus providing information to support many information intensive business processes such as the evaluation of design alternatives. This paper also presents a case study, i.e., the selection of transformers, to demonstrate the use of the ontology. In addition, limitations of the study have also been discussed.     

Mycotoxicoses “by proxy”

Health hazards due to the ingestion of certain mouldy foods have already been recognised. Less well known is the possibility that mycotoxins can be present in such products as milk, eggs, meat etc., which though not mouldy per se derive from animals that consumed feeds contaminated by secondary toxic metabolities of microorganisms.

Our knowledge of the extent to which such “mycotoxicoses by proxy” could be responsible for certain disorders considered “spontaneous” or “idiopathic” is fragmentary; appropriate investigations are urgently needed.

Evidence presented in this paper indicates that the use of livestock feeds contaminated by microorganisms producing mycotoxins, such as the oestrogenic zearalenone and its congeners, aflatoxins, ochratoxins etc., may present health hazards to man, as they pass into the milk and tissues of the animals. The susceptible young for whom milk is the main food are particularly vulnerable to mycotoxins “by proxy”. Attention is drawn to the possibility that such animal products may contain besides the parent compounds, some biologically active metabolites of mycotoxins, which though not detectable by the usual chemical tests, could contribute their potential for ill effects. These could be detected by appropriate testing in experimental animals.     

The efficiency of Norwegian road toll companies

This paper analyses the level of efficiency at which road toll companies are operated in Norway. Two alternative methods are applied for this purpose: data envelopment analysis (DEA) and stochastic frontier analysis (SFA). The data comprise a total of 20 toll companies that have been in operation in the period 2003–2008. The findings of the paper are as follows: 1) There is a great potential for efficiency improvement in the sector, irrespective of the method used, but the variation in the efficiency scores is dependent on the method used; 2) there is no evidence of economies of scale, as has been found by other authors, such as Odeck 2008, How efficient and productive are road toll companies? Evidence from Norway, Transport Policy. 15, 232–241 and, Amdal, E., Bårdsen, G., Johansen K. and Welde M., 2007. Operating costs in Norwegian toll companies: a panel data analysis. Transportation. 34, 681–695. These results suggest that toll companies could generate significant savings by employing industry best practices. Further, decision makers are warned not to be indifferent to the approach used i.e., DEA and SFA, as these may give very different results.     

The use of state-of-the-art transport models by policymakers – beauty in simplicity?

Transport demand models have a long history of being a major tool in transport policy making. However, whether they are truly used in decision-making processes, and if so, whether the knowledge they provide is actually understood, is questionable. The potential contribution they can make and the importance of such models is not disputed; however, evidence shows that many issues arise with their actual use that severely limits their potential contribution. Based on case study methodology and analysis of the use of models in the transport policy processes in two countries, the UK and Israel, this paper aims to provide empirical evidence of the issues contributing to limiting the potential contribution of models and to make recommendations for better utilisation of the knowledge they can produce. The main conclusion reached is that transport models must be made simpler if they are to contribute more than they currently do to decision-making in transport policy and planning.     

浅论美国老人护理建筑的设计理论与原则

美国和中国都正步入一个人口快速老龄化的时期,其老年护理产业也面临着由此而来的巨大挑战。基于美国的老年护理设施已经历了相当长时间的发展,借鉴其成功和失败的经验对中国有极其重要的意义。本文从美国人口老龄化带来的问题出发,就其老年护理建筑的分类、定义及发展状况、相关理论、设计原则、目前研究的热点和对中国的借鉴意义进行了论述,以期对中国老年护理建筑的发展起到一定的启示与推动作用。