Urban identity policies in Berlin: From critical reconstruction to reconstructing the Wall

After the fall of the Iron Curtain, the East-Central European cities had to re-invent themselves to quickly adapt to a globalising world. Urban identity production policies were usually geared to connect to a chosen pre-socialist “Golden Age”, ignoring the socialist past as a simple disturbance of a “normal” development path. This story the cities were to tell, however, frequently conflicted with the socio-economic realities of a rather unsmooth transformation process, making the socialist past part of the urban identity. In the case of Berlin, a post-socialist and at the same time a post-western-stronghold city, urban identity production is bound to be more complicated than anywhere else. After the failure of the policy to “critically reconstruct” the cosmopolitan metropolis of the 1920s and thus erasing the past of the divided city, policies developed in the run-up to the 20th anniversary of the fall of the Wall aim at turning the Cold War past into a central element of the story that is to support its urban identity, notably leading to the comprehensive re-emergence of the Berlin Wall in the cityscape. This policy – unmatched in other East-Central European cities – has its origins in a historic struggle for identity, leading to the questionable attempt to make “change” the main story Berlin is to tell. This theme however – in conjunction with the reconstructed Wall as image brand – may fall short of creating an urban identity accepted by large population parts.     

Fine particle collection of an electrostatic precipitator in CO2-rich gas conditions for oxy-fuel combustion

The collection of particles in CO₂-enriched environments has long been important for the capture of CO₂ in order to clean gases via oxy-fuel combustion. We here report on the collection characteristics of fine and ultrafine particles using an electrostatic precipitator (ESP) in a CO₂-enriched atmosphere. In order to understand the characteristics of particle collection in CO₂-rich gas mixtures, the ionic properties of a CO₂-enriched atmosphere was also investigated. The electrical mobility of the ions in a CO₂-enriched atmosphere was found to be about 0.56 times that found in a conventional air atmosphere, due to the higher mass of CO₂ gas compared to that of air. The low electrical mobility of ions resulted in a low corona current under CO₂-enriched conditions. The collection efficiency of particles in a CO₂-rich atmosphere for a given power consumption was thus somewhat lower than that found in air, due to the low quantity of particle charging in CO₂-enriched air. At the same time, higher temperatures led to the higher electrical mobility of ions, which resulted in a greater collection efficiency for a given power. The presence of a negative corona also led to a greater collection efficiency of particles in an ESP than that achieved for a positive corona.     

On the dual nature of intra-urban borders: The case of a Romani neighborhood in Istanbul

This essay questions the nature of intra-urban borders from a politico-ethical point of view. Namely: to what extent are intra-urban borders acceptable at a time of proliferating discourses about a borderless world, and open cities? We discuss this through a case study of Sulukule – a historic neighborhood home to a millennium old Roma community located within the historic city center of Istanbul – in the context of the urban renewal project launched by the local municipality. The often cited “humanitarian” pretext for the renewal project is “incorporating” the Sulukule’s poor Roma community into the city and tearing down the borders demarcating their ghetto. Eventually, this discourse of incorporation served to instigate a rapid episode of gentrification in the area. Offering a critical perspective on the municipality’s renewal project, and through a discussion of the often conflicting premises of the discourses of the “right to the city” and the “group right to difference,” this essay argues that intra-urban borders are “undecided” separators and calls for policy tools that are responsive to the enabling aspects of bordering processes.     

Determination and occurrence of phthalates, alkylphenols, bisphenol A, PBDEs, PCBs and PAHs in an industrial sewage grid discharging to a Municipal Wastewater Treatment Plant

Industrial and urban discharges release organic contaminants which might affect the quality of receiving waters if not properly eliminated in Wastewater Treatment Plants (WWTP). This study is aimed to evaluate the source, transport and fate of contaminants of industrial origin in a sewage grid discharging to a WWTP and finally to the sea. The sampling network covered an industrial and urban area and wastewaters, influents and effluents of a WWTP were analyzed using a newly developed multiresidual method to capture a wide range contaminants (phthalates, alkylphenols, bisphenol A, PBDEs, PCBs and PAHs). Alkylphenols and phthalates followed by PAHs were the main compounds detected at levels between 0.01 to 698 µg l^− 1 in the sewage pipelines. At the WWTP influent they were detected at concentrations up to 345 µg l^− 1. The contaminant load was eliminated in a 64-92% during the primary and secondary treatment of the plant. However, alkylphenols, phthalates bisphenol A and traces of PAHs were discharged with the effluent, producing a total net input of 825 g d^− 1 to the sea. The study of wastewaters herein proposed can be used to better predict the loads into WWTP to improve treatment conditions according to specific sewage inputs and to assess the risks associated with the continuous discharge of contaminants to receiving plants.     

Precoagulation-microfiltration for wastewater reuse

A range of coagulant chemicals and doses, up to 2 mg/L, were trialled on a microfiltration-based indirect potable reuse (IPR) pilot plant to evaluate their impact on membrane reversible and irreversible fouling. Jar tests revealed these doses to have negligible impact on organic matter removal, whilst scoping pilot trials showed them to have a positive impact on fouling rates. Initial trials carried out over a 6-h period suggested that ferric sulphate was the most promising of the coagulants tested with regards to irreversible fouling. Extended five-day trials using ferric sulphate at 0.5 mg/L were conducted at fluxes of 40-50 l/(m²h) (LMH). Operation at 50 LMH without coagulant resulted in rapid fouling and a subsequent shortening of the chemical cleaning interval. The addition of the ferric coagulant resulted in a reduction in both reversible and irreversible fouling to those levels experienced at 40 LMH, enabling sustainable operation. The use of low levels of coagulant thus enables the pilot plant to operate at a 25% increased flux, equating to a 20% reduction in membrane area and overall savings of >0.1 p per m³ for a seven year membrane life.     

Design of an individually controlled system for an optimal thermal microenvironment

Individually controlled microenvironment has potential to satisfy more occupants in a space compared to a total volume uniform environment typically used at present. The performance of an individually controlled system comprising a convection-heated chair, an under-desk radiant heating panel, a floor radiant heating panel, an under-desk air terminal device supplying cool air, and a desk-mounted personalized ventilation as used and identified by 48 human subjects was studied using a thermal manikin at room temperatures of 20 °C, 22 °C and 26 °C. At a room air temperature of 20 °C, the maximum whole-body heating effect of the heating chair, the under-desk heating panel, and the floor heating panel corresponded to the effect of a room temperature increase of 5.2 °C, 2.8 °C, and 2.1 °C, respectively. The effect was 5.9 °C for the combination of the three heating options. The higher the room air temperature, the lower the heating effect of each heating option or heating combination. The maximum whole-body cooling effect of the tested system was only −0.8 °C at a room air temperature of 26 °C. The heating and cooling capacity of the individually controlled system were identified. These results, analyzed together with results obtained from human subject experiments, reveal that both the heating and the cooling capacity of the individually controlled system need to be increased in order to satisfy most occupants in practice.     

Exergy concept and its application to the built environment

This paper discusses how a built environmental control system such as space heating and cooling can be described by the concept of “exergy”, which quantifies what is consumed by any working systems from man-made systems such as heat engines or buildings to biological systems including human body. The reason for the intensive and extensive use of exergy concept is to deepen our understanding of the built environment and thereby to develop a variety of low-exergy systems for future buildings. First, the essence of exergy balance equations is reviewed and then some results obtained from the recent exergy research were presented. The important findings described in this paper are as follows: (1) a volume of indoor air contains both of “warm” or “cool” exergy and of “wet” or “dry” exergy, whose values are comparable to each other especially for a hot and humid summer condition; (2) an ordinary air-source heat pump is basically a device to separate exergy supplied by electricity into warm, cool and dry exergies by consuming more than 85% of the supplied exergy; (3) there is a set of a little higher mean radiant temperature and a little lower air temperature, which provides with the lowest human body exergy consumption rate in winter season; (4) availability of cool radiant exergy of 20–40 mW/m² seems to play a key role for thermal comfort in a naturally-ventilated room in summer season; and (5) “cool” radiant exergy available from the sky in hot and humid regions amounts to 1000 mW/m², which is not necessarily small if compared to the values of cool radiant exergy to be supplied indoors.     

Activated soil filters (bio filters) for the elimination of xenobiotics (micro-pollutants) from storm- and waste waters

A technical scale (0.12 m³) activated soil filter (bio filter) has been used to eliminate diverse xenobiotics (organic micro-pollutants) such as organophosphate flame retardants, and -plasticisers, musk fragrances, DEHP, benzothiazoles and triclosan from water. Model experiments to treat combined sewer overflow, storm water and a post treatment of waste water were performed in controlled laboratory experiments. The indicator compounds were typical for waste water. Diverse chemical compound groups and a wide spectrum from the lipophilic (pK_ow = 5.9) to the hydrophilic (pK_ow = 2.6) were included. The system consisted of a layer with high organic content (with vegetation to prevent clogging), a sand filter and a gravel drainage layer. The organic layer was spiked with activated sludge to enhance biomass and biodegradation potential. Usually the elimination rates varied from 64% to 99%, with only one compound reaching as little as 17%. For a technical suitability assessment it was calculated how long these filters would be stable in eliminating organic compounds from water. The estimated operating times for such systems was found to be about 100 years for a stack height of 2 m a year in regard to most compounds in this study.     

Building simulation as an assisting tool in decision making: Case study: With or without a double-skin façade?

Implementation of double-skin façades in buildings has been an object of broad application in the recent years. In this presentation, a planned office building in the city-centre of Trondheim, Norway, is used as a case for considering whether a double-skin should be applied to the east façade in order to reduce the heating demand, thus making the double-skin façade a profitable investment. The building is modeled both with and without a double-skin façade with the building energy simulation program ESP-r. This paper describes how a double-skin façade with controllable windows and hatches for natural ventilation can be implemented in the simulation program. The simulation results indicate that the energy demand for heating is about 20% higher for the single-skin façade with the basic window solution compared to the double-skin alternative. However, by switching to windows with an improved U-value in the single-skin alternative, the difference in energy demand is almost evened out. The number of hours with excessive temperatures is, in contrast to other studies on the subject, not significantly higher for the double-skin alternative. However, the predicted energy savings are not sufficient to make the application of a double-skin façade profitable.     

Planning for the Disposal of the Dead

Problem: Concurrent with the dramatic increase in the nation's elderly population expected in coming decades will be a need to dispose of larger numbers of our dead. This issue has religious, cultural, and economic salience, but is not typically considered a planning problem. Although cremation rates are rising, burial is projected to remain the preferred alternative for the majority of the U.S. population, and urban space for cemeteries is limited in many communities.

Purpose: We outline issues related to cemeteries and burial, describe a number of alternatives to traditional cemeteries, and explain how planners might usefully contribute.

Methods: This work is based on a literature review.

Results and conclusions: Alternatives to the cemetery are emerging, but remain limited. Some require changes to laws or public perceptions. Planning practice could be advanced by case studies showing how to integrate burial grounds into existing communities and how to alter public policy to permit alternatives to burial.

Takeaway for practice: As population demographics change, environmental concerns intensify, and demand for urban space grows, future land use decisions will have to balance a diverse set of social, cultural, and environmental expectations, including taking into account burial practices. There are only a handful of alternatives to traditional burial in a cemetery: burial in a multiple-use cemetery; natural burial; entombment in a mausoleum; cremation, with the ashes preserved in a columbarium or scattered elsewhere; and burial in a grave that will be reused in the future. This article provides planners with information about each of these alternatives, examples of how the planning process can address disposal of the dead, suggestions for avoiding environmental externalities, and ideas for better integrating the landscapes of death into community life.

Research support: None     

Work–life strategies in the Australian construction industry: Implementation issues in a dynamic project-based work environment

A participatory work–life balance intervention was implemented in a medium-sized construction contracting organization based in Melbourne, Australia. Weekly data capturing the number of hours worked, satisfaction with work–life balance and capacity to complete required tasks at work and at home were collected for 25 consecutive weeks. Data was subjected to time series modeling procedures and weekly work hours were found to significantly predict participants' overall satisfaction with work–life balance, and capacity to complete tasks at work and at home. The occurrence of ‘long weekends’, i.e., a period of three days away from work arising as a result of a public holiday coinciding with a ‘rostered day off’, was also found to predict workers' capacity to complete tasks at home. An evaluation workshop explored workers' experiences of a work–life intervention. Participants' were generally positive about the organization's support of their work–life balance, however areas for improvement were identified, such as the need for better communication of work–life strategies and to address the ‘long hours’ culture within the organization. The research presents a participatory framework for improving the work–life balance of project-based construction workers.     

Quasi-dynamic energy-saving judgment of electric-driven seawater source heat pump district heating system over boiler house district heating system

The electric-driven seawater source heat pump district heating system is a renewable energy utilization system, but this cannot guarantee the energy-saving effect of the system. The static energy-saving judgment between this system and the conventional boiler house district heating system was provided in a former research paper. However the static method has proved to be a very rough evaluation method and may lead to misjudgment as well. So a quasi-dynamic method, taking the total energy consumption during a whole heating season into consideration, is established in this paper. The energy-saving index turns out to be the expression of the lower limit of the average COP of the seawater source heat pump unit throughout the heating season (COP_h,mc). Then a case study is presented to show how the index of COP_h,mc and the actual average COP of the heat pump unit throughout the heating season (COP_h,ma) are calculated. The calculation results show that the quasi-dynamic method improves the calculation accuracy dramatically, and thus provides a better solution to the quantitative energy-saving evaluation of the electric-driven seawater source heat pump district heating system.     

On the distribution of bids for construction contract auctions

The statistical distribution representing bid values constitutes an essential part of many auction models and has involved a wide range of assumptions, including the Uniform, Normal, Lognormal and Weibull densities. From a modelling point of view, its goodness is defined by how well it enables the probability of a particular bid value to be estimated – a past bid for ex-post analysis and a future bid for ex-ante (forecasting) analysis. However, there is no agreement to date of what is the most appropriate form and empirical work is sparse. Twelve extant construction data-sets from four continents over different time periods are analysed in this paper for their fit to a variety of candidate statistical distributions assuming homogeneity of bidders (ID not known). The results show there is no one single fit-all distribution, but that the 3p Log-Normal, Fréchet/2p Log-Normal, Normal, Gamma and Gumbel generally rank the best ex-post and the 2p Log-Normal, Normal, Gamma and Gumbel the best ex-ante – with ex-ante having around three to four times worse fit than ex-post. Final comments focus on the results relating to the third and fourth standardized moments of the bids and a post hoc rationalization of the empirical outcome of the analysis.     

Upgrading the Arlberg tunnel to current safety standards

Austrian road tunnels within the Trans-European Road Network (TERN) must fulfil the requirements of the Directive 2004/54/EC (European Commission, 2004) not later than April 2019. This regulation has to be applied to all tunnels in the TERN with a length of more than 500 m, whether they are in operation, under construction or at design stage, and aims at ensuring a minimum level of safety for road users. One of the main features of this directive is the requirement for providing an egress possibility to a safe environment every 500 m throughout the whole tunnel.The Arlberg road tunnel has a length of some 15.5 km and is in operation for more than 35 years. It is a single tube tunnel operated with bi-directional traffic, but carries a quite low traffic volume. Hence, the construction of a second tube is not really cost effective. Currently the tunnel is equipped with a transversal ventilation system with remotely controlled smoke extraction dampers providing smoke extraction every 100 m. The maximum distance between egress possibilities to a save environment is some 1500 m. Due to the high costs of a construction of a second tube or a parallel running escape gallery, a novel solution was found. The existing fresh air duct will be used as safe escape way between the existing egress possibilities. This solution has big impacts on the ventilation system and on the requirements for thermal structure protection of the new egress ways, i.e. the fresh air duct. In order to overcome this problem, massive changes in the ventilation design have to be performed, accompanied by the installation of a high-pressure water-mist system for structure protection.     

Pulse extraction and displacement response evaluation for long-period ground motions

Long-period ground motions with directivity and/or path effects are often characterised by the presence of velocity and acceleration pulses in the lowermost frequency range. An objective of this article is to present a discrete-time signal processing method for isolating these pulses. In this method, the velocity and the acceleration pulses are identified by applying a low-pass discrete-time filter H_lp (ω) at a suitable cut-off frequency f _c to the Fourier transforms of the original velocity and acceleration ground motion time histories, respectively. Another objective of this article is to present a mathematical expression for evaluating the linear displacement response of a single degree-of-freedom (SDF) system by simultaneous application of two frequency modulators, H_lp (ω) and H_u (ω), to the original ground excitation. By using only the pulse component of the ground motion as the excitation force, it is shown that the displacement response of the SDF system with natural period exceeding a certain value referred to as the cut-off period T _c is quite comparable with that due to the original ground excitation. Also, for ground motions that contain multiple-period pulses, it is shown that the displacement response spectrum of the SDF system exhibits multiple peaks at different natural system periods T _n.     

Planning paradigm in the madina: order in randomness

The sustainability of the current madina – despite its physical decay – reveals hidden dynamic urban mechanisms that have proved its reliability. Far from falling in the Orientalist synthesized urban images, and their counterparts, the very Islamic constructed ones, this paper seeks instead to argue on the planned aspects of a madina. The concept of planning shall be revisited in order to discern its intrinsic urban order. This implies no analogy with the contemporary urban planning. Its planning observed legal, urban and social ideals, creating neither an absolute aestheticized physical form nor dictating a totalizing function. The review of the planning paradigm in the madina would provide a genuine meaning of its name that had been altered to médina – a colonial term referring to a stagnant walled entity. Arguably, without a sense of order and planning, the sewer would flood its alleys, potable water would never reach its fountains, and one would never escape its twisty roads. It would be absurd to view madina as being totally random, and to assume that it did not generate a level of a pre-meditated planning. This paper poses decisive questions about the relevance of the mad ina in the age of modern urbanism, and deduces urban lessons for contemporary planners.     

Defining relational contracting from the Wittgenstein family-resemblance philosophy

There has been an increasing interest in the concept of relational contracting (RC) in construction starting from the late 1990s. RC embraces and underpins different forms of collaborative approaches, including partnering, alliancing, joint venture and other collaborative working arrangements and better risk sharing mechanisms. By applying Nyström's and Yeung et al.'s similar approaches to define construction partnering and construction alliancing respectively, this paper focuses on RC and family-resemblance. A significant contribution to new knowledge is believed to have been made in providing a concise and comprehensive approach in defining the similar and yet different key components of RC by using a Sunflower Model. The development of this innovative Model is based on the German philosopher, Ludwig Wittgenstein's family-resemblance philosophy. His idea is that a complex concept can be understood as a network of overlapping similarities. Based on the reported literature, it is concluded that there are always five core elements included in construction RC. They are “commitment”, “trust”, “cooperation and communication”, “common goals and objective”, and “win–win philosophy”. In addition to these core elements, a number of different non-core elements, or called petals, can be added to constitute a specific variant of RC in construction. The contribution can be of paramount importance to both the research community and the construction industry. By using this innovative theoretical framework to define construction RC, industrial practitioners may find the Sunflower Model useful in the procurement of a construction RC project. The Sunflower Model can be applied to explain the underlying concepts and as a common starting point for discussions between a client and a contractor on how to procure a RC project, thus avoiding any misinterpretations of what a RC project is.     

Study on sustainable redevelopment of a densely built-up area in Tokyo by introducing a distributed local energy supply system

“Distributed local energy systems” had been expected to rationalize the supply of energy to built-up areas, but until now very little research has been performed to estimate the effect of their application to actual cities. In this research, therefore, a future vision for the year 2030 in the Sancha Area (SANCHA VISION 2030), a typical densely built-up area in Tokyo, has been elaborated including a simulation to estimate benefits from the application of distributed energy systems in terms of reduced energy consumption and CO₂ emissions as well as mitigation of the heat-island phenomenon. As a result, it was demonstrated that a “distributed local energy system”, which provides a district with both electrical power and heat through an integrated distribution system, may contribute to a considerable improvement in energy efficiency for those areas. In addition, it may also provide other benefits, including enhancement of living amenity and urban security in times of emergency.     

Experimental and numerical study of a full scale ventilated enclosure: Comparison of four two equations closure turbulence models

Full-scale experimental and computational fluid dynamics (CFD) methods are used to investigate the velocity and temperature fields in a mechanically ventilated enclosure. Detailed airflow fields are measured in three cases of ventilation air temperature: an isothermal case, a hot case and a cold case. The ventilation system creates an axisymmetric jet which is developing near the ceiling. The experimental data are used to test four two equations turbulence models: a k–ε realizable model, a k–ε RNG model, a k–ω model and a k–ω SST model. It is found that, even if the models can predict reasonably the hot and isothermal cases global values of temperature and velocity, none of the models is reliable concerning the cold case. Moreover, a detailed analysis of the jet shows that none of the models is able to predict the exact experimental velocity and temperature fields.     

The definition of partnering as a Wittgenstein family‐resemblance concept

This article on partnering and family‐resemblance makes two contributions to the debate about the definition of partnering in construction. The first is a distinction between general prerequisites, components and goals when discussing the concept. In order to understand what is specific about partnering the focus should be on the components, which are identified through a literature review. The second contribution is to apply Ludwig Wittgenstein's idea of family‐resemblance to the partnering concept. His idea is that a complex concept can be understood as a network of overlapping similarities. From the literature review it is concluded that there are two necessary components in partnering – trust and mutual understanding – and that a number of different components can be added to form a specific variant of partnering. This provides a new method to define the vague and multifaceted concept of partnering in a flexible and structured way.