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1.
This study examined the relationships between four standardized measures of spatial ability—the Embedded Figures Test (EFT), the Mental Rotations Test (MRT), the Differential Aptitude Spatial Relations subtest (DAT), and the Building Memory Test (BMT)—and two measures of environmental knowledge. Three hundred and fifty-three college undergraduates were administered the EFT, MRT, DAT, BMT and two measures of environmental knowledge-a landmark location (LM) and route knowledge (RK) task. The two environmental knowledge tasks were based on a slide-simulated walk through an unfamiliar urban environment. A principal components analysis of the above six measures produced two factors; one consisting of the four spatial ability tests, and the other the two environmental knowledge tasks. The correlation between the two factors was 0·37, indicating that the spatial ability factor accounted for 13·69% of the variance in the environmental knowledge factor.  相似文献   

2.
Use of wood frames from sustainable forestry instead of non-wood frames in multi-storey buildings can reduce primary energy use and carbon dioxide emissions in construction. However, construction actors might have different perceptions towards wood frames than towards steel and concrete frames. Such perceptions may influence the actors’ decision to adopt wood frames. In this study we use a web-based questionnaire to assess Swedish architects’ perceptions, attitudes and interest towards steel, concrete and wood frames in multi-storey buildings (n = 412). Results indicate that the responding architects find concrete the most suitable frame material in buildings of 3-8 storeys, mainly because of the performance of concrete with regards to the engineering aspects (e.g. stability and fire safety) that were considered important in the choice of frame material. Although wood is considered the least suitable frame material, the overall attitude towards, and interest in, using wood is positive and related to the perceived environmental benefits of wood. This may derive from an increased discussion of and information about the environmental impact of buildings. Wood may be perceived as new and innovative while not considered as adequately proven as steel and concrete with regards to engineering aspects.  相似文献   

3.
The aim of this study was to assess the effects of forest management on carbon sequestration in forests and wood products by using a gap-type forest model interfaced with a wood product model. The assessment is based on total carbon sequestration, i.e. the amount of carbon left in vegetation, litter, soil organic matter and products when the flows of carbon back to the atmosphere have been subtracted. Thirty mixed-species stands, representing medium fertility sites in southern Finland, were included in each simulation for 300 years under current climatic conditions and predicted conditions of changing climate. The average total balance for the first 100 years was higher in the unmanaged system than in the managed system, but for the second and third 100-year periods the results were clearly opposite. Differences in the total balance between the treatments were larger during the first 100 years than over the whole 300-year period. Under conditions of changing climate, differences in carbon sequestration between management options were more pronounced than under current climatic conditions. Under current climatic conditions with the 100-year time frame, the ratio between the total annual balance and annual gross production was 0·208–0·289. Over the whole 300 years, however, efficiency was much lower, 0·088–0·121. Under changing climatic conditions, efficiency was also lower, 0·182–0·252 and 0·081–0·096, respectively. Different management alternatives clearly produced different amounts of timber for the production process; under conditions of changing climate, timber production was substantially enhanced. However, total carbon storages at the end of the simulation varied less than timber production. In the managed system, the flow back into the atmosphere was largest from litter, 41–51% of the total outflow, the flow from vegetation was 23–28%, from soil organic matter 22–25%, emissions from products 1–7%, and emissions from landfills 0–3%. If emissions due to the use of machinery in timber harvesting and transportation were included, they made up only 0·03–0·33% of the total outflow.  相似文献   

4.
Tools for assisting human navigation, especially in-vehicle systems, have been extensively investigated. However, few studies have explored the design of speech-based over-the-phone guidance systems. This study examined the effect of landmarks' use and the effect of landmarks’ frames of reference in route instructions on navigation efficiency during map navigation tasks and satisfaction. Twenty-seven participants performed map navigation tasks using a simulated speech navigation system in three experimental conditions: instructions containing no landmarks, instructions containing landmarks located without reference to either the traveler’s body or the surrounding environment, and instructions containing landmarks located with respect to the traveler’s body. Navigation performances on maps were higher and landmarks enable participants to make fewer directional errors and find their routes more efficiently. Satisfaction levels and navigation performances were lower when instructions did not contain any landmarks. Landmarks’ frames of reference shifting turned out to be different between human-human situations previously used and human-computer situations used here.  相似文献   

5.
Choices of where to carry out everyday activities in large-scale environments were conceptualized as a process of forming ‘travel plans’, and, to test a model of how such plans are formed, three experimental simulations of a planning task were performed in the laboratory. In Experiment 1, subjects (high school students) were found to choose a shortest route to travel between a number of actual, familiar locations in a town by first choosing the order between the locations that minimized straight-line (Euclidean) distances, then choosing the shortest paths between the locations in the constrained order. The order choices were, in Experiment 2, found to be made by minimizing distance locally rather than globally, except in some cases when ‘spatial configurations’ of the locations were discovered. Both the results of this experiment and of Experiment 3 suggested that such discoveries were facilitated by a simultaneous representation of the locations which was possible when they were positions on a display, committed to short-term memory or available for perceptual inspection, but to a less extent when they were actual locations.  相似文献   

6.
This study investigates the adaptivity of wayfinding strategies in a real-world setting of a multi-building ensemble. Familiarity with the environment, map usage and verbal vs. visual task instructions were systematically varied. Measures included path choices, wayfinding performance and information usage. Thirty-two participants had to find eight goals in a multi-level building ensemble consisting of two distinctive building parts. It was tested whether the standard wall-mounted floor maps found in the majority of public buildings can help navigation in a complex unknown environment. Unfamiliar users tried to make use of these plans more frequently, but were not able to compensate for spatial knowledge deficits compared to participants familiar with the setting. Two strategies of multi-level wayfinding were compared with respect to a region-based hierarchical planning approach. Strategy selection could be shown to be highly adaptive to spatial properties of the environment as well as characteristics of the task instruction, i.e., spatial precision of target information. Overall, the strategy of moving horizontally into the target building prior to vertical travel was shown to be more effective in this multi-building setting.  相似文献   

7.
This study concerns design features of urban parking lots which can increase the perception of such areas as both safe and attractive. College students evaluated the attractiveness and perceived security associated with 180 scenes of parking lots adjacent to commercial and multi-family residential structures in Atlanta and Athens, Georgia, U.S.A. High intergroup correlations (r > 0·90) indicated the reliability of evaluations of both perceived features. Regressions of physical features on perceived security ratings and attractiveness ratings yielded highly predictive models (R2 = 0·76 and 0·80, respectively). For both sets of ratings a Maintenance and Design factor accounted for the most variance. Although attractiveness ratings were higher as the total amount of vegetation increased in a scene, security was in general rated higher only when vegetation was well maintained and appeared to be installed as part of a landscape design. Attractiveness was generally higher for multi-family residential scenes than for commercial scenes. Perceived security was higher for frontal views of structures, especially when entrances were proximate to the viewer. Research implications are discussed in terms of the impact of natural features in urban areas for increasing attractiveness and reducing fear of crime.  相似文献   

8.
Effect of oxygenated liquid additives on the urea based SNCR process   总被引:1,自引:0,他引:1  
An experimental investigation was performed to study the effect of oxygenated liquid additives, H2O2, C2H5OH, C2H4(OH)2 and C3H5(OH)3 on NOx removal from flue gases by the selective non-catalytic reduction (SNCR) process using urea as a reducing agent. Experiments were performed with a 150 kW pilot scale reactor in which a simulated flue gas was generated by the combustion of methane operating with 6% excess oxygen in flue gases. The desired levels of initial NOx (500 ppm) were achieved by doping the fuel gas with ammonia. Experiments were performed throughout the temperature range of interest, i.e. from 800 to 1200 °C for the investigation of the effects of the process additives on the performance of aqueous urea DeNOx. With H2O2 addition a downward shift of 150 °C in the peak reduction temperature from 1130 to 980 °C was observed during the experimentation, however, the peak reduction efficiency was reduced from 81 to 63% when no additive was used. The gradual addition of C2H5OH up to a molar ratio of 2.0 further impairs the peak NOx reduction efficiency by reducing it to 50% but this is accompanied by a downward shift of 180 °C in the peak reduction temperature. Further exploration using C2H4(OH)2 suggested that a 50% reduction could be attained for all the temperatures higher than 940 °C. The use of C3H5(OH)3 as a secondary additive has a significant effect on the peak reduction efficiency that decreased to 40% the reductions were achievable at a much lower temperature of 800 °C showing a downward shift of 330 °C.  相似文献   

9.
FeSO4·xH2O is generated in large amounts in galvanizing workshops. It can be reutilized by conversion to Fe2O3. In this study, the recovery of Fe2O3 from FeSO4·xH2O formed in the galvanizing process has been examined. The experimental work was carried out at various temperatures and times in the oxidizing medium. The reaction temperatures and times were selected as 450, 500, 550, 600, 650, 700, 800 and 900°C, and 15, 30, 45, 60, 90 and 120 minutes, respectively. In order to determine the amount of Fe2O3, a titrimetric method was applied. The reaction products were characterized by means of IR and XRD techniques.The extent of conversion is low at temperatures below 650°C. Almost all of the iron (II) sulfate in the original sample was converted to iron(III) oxide at 650°C (120 min), 700°C (90 min), 800°C (60 min) and 900°C (45 min).  相似文献   

10.
11.
Two experiments examined whether differences in elevation of the terrain are encoded in cognitive maps of outdoor environments. In Experiment 1, two groups of subjects who had travelled a varying number of times between a set of locations made direct estimates in metres of the differences in elevation between the locations. The results showed that subjects in both groups had knowledge of elevation but those for whom the terrain was less familiar tended to exaggerate the differences. In Experiment 2, decision times were measured of responses to the question whether one location is below or above another one. Neither for subjects who were more, nor for subjects who were less familiar with the terrain, did the decision times vary with the distances between the locations, thus failing to support the hypothesis that differences in elevation are retrieved by a process of ‘mental travel’.  相似文献   

12.
13.
Design and operating parameters, and cause and effect relationships among feedstocks and products in the pyrolysis of waste polymers are needed if this method of processing is to be used for energy recovery from waste plastics. The purpose of this study was to quantify the effect of various operating factors for the pyrolysis of common polymeric wastes. Experiments were performed using a conventional retort tube as a batch reactor. The operating factors considered were temperature and reaction time at constant heating rate. High density polyethylene (PE) and polystyrene (PS), the most common plastic waste in Korea, were used singly and in mixture.The pyrolysis time for maximum oil production from a PE-PS mixture was shorter than in the case of PE alone, showing an enhancement effect from the PS. The maximum gas production time from PE-PS mixtures was shorter than for PE alone at 500° C; above 600° C, this does not occur. Small aromatic compounds (which can be valuable) are produced at maximum with an 1:1 mixture of PE and PS at 600° C, showing the possibility of process control for the maximum recovery of desirable pyrolysis products. The maximum yield of toluene, xylene, styrene, and 1-propenyl benzene were 8.6, 8.9, 51.0 and 7.4 wt.% of feed for pyrolysis PS at 700° C, respectively. For naphthalene, it was at 700° C with 1:1 PE:PS (by wt.). The maximum recovery was 1.3 wt.%. Diels-Alder theory can explain the formation of aromatic compounds in the pyrolysis products. The yield of these secondary pyrolysis products can be controlled by reaction time, pyrolysis temperature and mixing ratio of plastic wastes in the pyrolysis feed.  相似文献   

14.
While the age of physical environments is the central tenet of historic preservation, there is a lack of empirical evidence about how everyday people actually value, perceive, and experience age as an intrinsic part of an urban environment. In order to ameliorate this knowledge deficit, this study employs phenomenology to understand the lived experience of being in a “new” versus an “old” or “historic” urban residential environment. The new environment is the I'On new urbanist development in Mt. Pleasant, South Carolina, and the old environment is the location of the United States' first historic district in Charleston, South Carolina. These locations are approximately within five miles of each other. In both places, the physical characteristics of the built environment are remarkably similar in density, form, layout, and design, but the age is dramatically different. Through photo elicitation techniques and interviews, the results of this study reveal that residents of historic Charleston and I'On value their built environments in remarkably similar ways. Surprisingly, elements that evoke a strong sense of attachment tend to be landscape features, such as gates, fountains, trees, and gardens rather than buildings. The informants valued the “mystery” that they felt was part of the landscape and which consisted of layered elements such as fences, gates, and paths, such that these features (including buildings) had to be “discovered.” Lastly, the informants strongly valued landscapes that showed “people care” through regular maintenance. The essential difference in people's experience and valuation of the new environment (I'On) and the old environment (historic Charleston) is in the older environment's ability to instill creative fantasies in the minds of the informants based on a hypothetical past of their own creation. The informants in I'On did not share these kinds of meanings.  相似文献   

15.
The current study asks how young children judge behaviors that harm the environment as compared to moral transgressions, social-conventional transgressions, and personal choices. This study also questions whether children are more likely to cite biocentric or homocentric reasons when justifying their judgments of environmentally harmful behaviors. To answer these questions, sixty-one 6–10 year olds were asked to judge the severity of various actions that impact the environment. For comparison, participants also judged moral transgressions, social-conventional transgressions, and personal choices. Children judged actions that harm the environment more severely than social-conventional transgressions but not as severely as moral transgressions. When justifying their judgments of these environmentally harmful behaviors, participants were more likely to reference biocentric reasons as compared to homocentric reasons. The findings suggest that children perceive harm to the environment as bad, but harm to humans as worse.  相似文献   

16.
In this research, nanoporous zeolite T membranes were synthesized at three levels of synthesis temperature: 100, 120 and 140 °C and synthesis time: 15, 30 and 50 h and characterized by gas permeation. Effects of synthesis parameters on CO2 and CH4 permeances and CO2/CH4 ideal separation factors were studied. All experiments were conducted at 1 bar feed pressure and 30 °C module temperature. Normally, it is anticipated that increasing synthesis temperature and synthesis time increase gas permeances and consequently decrease ideal separation factor. This prediction was not observed in the case of synthesis temperature increase from 100 to 120 °C as well as synthesis time increase from 15 to 30 h, due to the dual effect of increasing synthesis temperature and synthesis time on gas permeances and ideal separation factor. More zeolites are deposited and larger crystals are formed at higher synthesis temperatures and times. Forming the larger crystals accelerates the rate of zeolite layer integration, which is responsible for gas separation, in one hand and reduces the density of deposited zeolite layer on the support, due to the formation of more voids, on the other hand. In terms of maximizing the CO2/CH4 ideal separation factor, medium synthesis temperature and synthesis time (120 °C and 30 h) can be selected, however, maximum gas permeances are obtained at low levels of synthesis temperature and time (100 °C and 15 h). According to the ranges of gas permeances (10−11 to 10−6 mol/m2 s Pa) and CO2/CH4 ideal separation factors (1.4–70.3), it is concluded that the zeolite T membranes synthesized at optimum conditions can be employed for membrane separation of CO2/CH4 mixtures.  相似文献   

17.
Crosslinkable poly(4-methyl-2-pentyne) (PMP) membranes were cast from carbon tetrachloride solutions containing PMP and either 4,4′-diazidobenzophenone or 4,4′-(hexafluoroisopropylidene)diphenyl azide. The composite membranes were transparent and homogeneous and were crosslinked by UV irradiation at room temperature or thermal treatment at 180 °C. Low levels of the bis(aryl azide) (1–4.5 wt%) were effective in rendering the membranes insoluble in cyclohexane and carbon tetrachloride, both are good solvents for PMP, thus PMP can easily be converted to mechanically stable membranes with permeabilities and selectivities comparable or higher than those of the well-known poly(dimethylsiloxane) (PDMS). The permeabilities of O2, N2, H2, CH4 and CO2 were measured. Compared to pure PMP, the crosslinked membranes containing bis(aryl azide) had lower permeabilities and higher selectivities, consistent with a reduction in free volume.  相似文献   

18.
Brazil produces approximately 242,000 t of waste per day, 76% of it being dumped outdoors and only 0.9% recycled, including composting, which is an alternative still little known in Brazil. In search of a better destination for residues produced by domestic activities, composting stands as a feasible alternative. Organic compost from waste may be used for various purposes, among which are soil recovery, commercial production, pastures, lawns and reforestry and agriculture. However, the quality of the compost determines the growth and the development of plants. The effect of compost made from urban waste on corn plant (Zea mays L.) growth was investigated. Two types of compost were used: the selected compost (SC), produced from organic waste selectively collected; and the non-selected compost (NSC), taken from a 15-year-old cell from the Canabrava land-fill, located in Salvador, Bahia, Brazil (altitude 51 m, 12°22′–13°08′S, 38°08′–38°47′W). Corn was seeded in polyethylene pots, with soil-compost mixing substrate in the proportion of 0, 15, 30, 45 and 60 t ha−1 equivalent doses. Chemical analyses of the compost and growth properties of the plant like chlorophyll content; height and stem diameter; aerial and radicular dry biomasses, were used to evaluate compost quality. Plants cultivated with SC presented a superior gain, being of 52.5% in stem diameter, 71.1 and 81.2% in root and stem biomasses, respectively. Chlorophyl content alterations were observed in plants from treatments using 30 t compost ha−1 dose onwards. Conventional and multivariate statistical methods were used to evaluate these results. The beneficial action of organic compost in plant growth was confirmed with this research.  相似文献   

19.
Infrastructure resilience has become a primary objective for homeland and national security organizations over the past decade. Recent initiatives have focused on resilient building design, and one approach under consideration is a voluntary resilience certification program for commercial buildings. The intent of this program would be to encourage the adoption of resilient design practices in construction and planning of the buildings. While resilience may be a frequently discussed concept within the security communities, its level of awareness within the construction, design, insurance, and building owner communities is not well known. Given the voluntary nature of the certification program under consideration, program development requires a comprehensive understanding of resilience as defined by the commercial building stakeholders. Toward this end, Sandia National Laboratories conducted a study of stakeholder perspectives on resilience to ascertain factors that would serve as motivation for participation in the resilience certification program. This paper describes how Sandia performed the study and the resulting conclusions. One of the key conclusions that the study found is that the term resilience is unfamiliar to many and inconsistently defined across the industries. Those familiar with the term frequently linked it to sustainability concepts. The study also found that increased participation in the resilience certification program is very likely affected by demonstrable returns on resilience investments and a public–private partnership model for program administration.  相似文献   

20.
Cooking devices could be evaluated for their performance using solar cookers as a bench mark. Accordingly, any device rejecting heat at 100°C and 80 W could be used for cooking. On this criteria diesel engine exhaust which rejects heat at 135–400°C and 3.8 kW is an excellent source. Methods of designing cookers to meet different end-purposes are discussed. Feasibility of cooking different types of food under exhaust gas temperature regimes is indicated.  相似文献   

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