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1.
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.  相似文献   

2.
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.  相似文献   

3.
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.  相似文献   

4.
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.  相似文献   

5.
Hatt JW  Germain E  Judd SJ 《Water research》2011,45(19):6471-6478
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.  相似文献   

6.
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  相似文献   

7.
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.  相似文献   

8.
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 (pKow = 5.9) to the hydrophilic (pKow = 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.  相似文献   

9.
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.  相似文献   

10.
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.  相似文献   

11.
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 (COPh,mc). Then a case study is presented to show how the index of COPh,mc and the actual average COP of the heat pump unit throughout the heating season (COPh,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.  相似文献   

12.
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.  相似文献   

13.
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 Hlp (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, Hlp (ω) and Hu (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.  相似文献   

14.
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.  相似文献   

15.
Contamination from untreated wastewater leakage and related bacterial contamination poses a threat to drinking water quality. However, a quantification of the magnitude of leakage is difficult. The objective of this work is to provide a highly sensitive methodology for the estimation of the mass of untreated wastewater entering karst aquifers with rapid recharge. For this purpose a balance approach is adapted. It is based on the mass flow of caffeine in spring water, the load of caffeine in untreated wastewater and the daily water consumption per person in a spring catchment area. Caffeine is a source-specific indicator for wastewater, consumed and discharged in quantities allowing detection in a karst spring. The methodology was applied to estimate the amount of leaking and infiltrating wastewater to a well investigated karst aquifer on a daily basis. The calculated mean volume of untreated wastewater entering the aquifer was found to be 2.2 ± 0.5 m3 d−1 (undiluted wastewater). It corresponds to approximately 0.4% of the total amount of wastewater within the spring catchment.  相似文献   

16.
“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.  相似文献   

17.
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.  相似文献   

18.
This article discusses the measurement and simulation of a first generation prototype of Virtual Natural Lighting Solutions (VNLS), which are systems that can artificially provide natural lighting as well as a realistic outside view, with properties comparable to those of real windows and skylights. Examples of employing Radiance as a simulation tool to predict the lighting performance of such solutions are shown, for a particular case study of a VNLS prototype displaying variations of a simplified view of overcast, clear, and partly cloudy skies. Measurement and simulation were conducted to evaluate the illuminance distribution on workplane level. The key point of this study is to show that simulations can be used to compare an actual VNLS prototype with a hypothetical real window under the same sky scenes, which was physically not possible, since the test room was not located at the building׳s façade. It is found that the investigated prototype yields a less rapidly drop illuminance distribution and a larger average illuminance than the corresponding real window, under the overcast (52 lx compared to 28 lx) and partly cloudy (102 lx compared to 80 lx) sky scenes. Under the clear sky scene, the real window yields a larger average illuminance (97 lx) compared to the prototype (71 lx), due to the influence of direct sunlight.  相似文献   

19.
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.  相似文献   

20.
The three-dimensional isothermal flow patterns and mass fluxes in a full-scale, pitched-roof, single-span greenhouse were numerically resolved, and data from tests on a full scale were used to validate the code, the inlet boundary conditions and the greenhouse design grid method. For numerical solution of turbulent flow, a high-Reynolds-number k-ε model is suitable. Computational domain sizes were selected so as to fulfil the requirements of free-stream conditions whilst ensuring that grid geometrical characteristics satisfy the physical limitations of the standard k-ε model. A special feature of a case of a wind blowing parallel to a ridge (0°) is that the flow in the leeward half of the greenhouse comprises two vortexes with opposite senses of rotation, which bring in air mass through the vents and deliver it to the windward half. A spiral type of flow was found for winds blowing at 15-75° to the ridge direction: part of the air enters via the windward wall vent near the leeward gable-wall and emerges through the leeward roof vent near the windward gable-wall.Mass fluxes and flow patterns on wind direction, and on the opening angles of the windward and leeward vents. Thus, the ventilation rate induced by a wind directed perpendicularly to the greenhouse ridge is 4-4.9 times as great as that induced by a wind parallel to the ridge. A ventilation rate of a simulated greenhouse type was found to be significantly less responsive to a change in wind direction from 45° to 90° than to one from 0° to 45°. Present numerical results are in good agreement with those of other experiments and observations.  相似文献   

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