This article involves designing the Nominal cover thickness by means of fuzzy inference system(FIS) for quantitatively representing the environment load coefficient to reinforced concrete in corrosive environment. In this work, several variables defining the quality of concrete and environment condition, viz. environment load coefficient(ELC), were treated as fuzzy variables. To qualify ELC the environment conditions of cycle degree of wet-dry, relative humidity, distance from coast and temperature were used as input variables. To determine the Nominal cover thickness a qualified ELC, concrete grade, and water-cement ratio were used. The membership functions of each fuzzy variable were generated from the engineering knowledge based on some references as well as some international codes of practice.
The restraining conditions of this work are as follows;
1. The knowledge bases for generating the rule base of fuzzy inference system are derived just from some references as well as BS 8110 and BS EN 206-1/BS 8500.
2. The procedure of this study is applicable only to the corrosive environments.
3. It is limited to the cover to reinforcement for normal building structures with an intended service life of at least 50 years.

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Heat transfer process and natural ventilation driven by a solar chimney attached to a sidewall of building are investigated with CFD technique (MITFLOW) in detail. In this paper, conditions and parameters studied in the modelling study are the cavity width of the solar chimney, the wall temperature, the height and breadth of the solar chimney, the ratio of outlet area to inlet area as well as the outlet location of the solar chimney. The ranges of calculation parameters focused on a solar chimney with single-sided solar collector (single-sided heated wall) cover following conditions: solar chimney length L = 0.5m~5.0m, breadth B=0.1m~0.5m, height H=2.0m~5.0m, and B/H=0.05~0.25. Heated wall surface temperature Tw is changed in the range of 30°C~70°C; the ratio of the outlet area to inlet area A_r is changed in the range of 0.6~1.0. It is found that for given building geometry and inlet areas, there is an optimum cavity width at which a maximum airflow rate can be achieved. Based on the prediction, the airflow rate reaches maximum when B/H is approximately 1/10. It is also found that for given chimney geometry, solar chimney ventilation flow rate can be increased with the enhancement of chimney height only the cross sectional area no more than the critical area, because cross section area has a strong effect on the transitional and/or turbulent convective heat transfer in an enclosure. From the view of economy technology, the optimized height of a solar chimney can be determined according to the optimized section ratio of breadth to height and available breadth in practice. On the analysis of CFD prediction, it is noted that optimized ventilation flow rate can be obtained when the outlet area takes the same area as the inlet area. Generally, there is good agreement among the numerical results, available experimental data from literature and theoretical analysis of natural ventilation from the solar chimney.

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In this study, a two storied single family house with solar floor and domestic hot water heating system is simulated to examine the usefulness of the simulation for predicting the indoor thermal environment and energy consumption to evaluate the system performance throughout a year. The effects of the solar floor and hot water heating system were evaluated with comparison of the simulated results for the cases with and without solar heating system. The results showed that the solar house provided comfortable environment with an average annual total purchased electric power of 40.4 GJ/year, which was lower than that of the house without solar heating system by 17 %. In addition, the effect of tilt angle of solar collector on the total energy performance of this house was examined to discuss the suitable angle in considering roof design of the house. It was found that the effect of collector tilt angle on the solar energy contribution was much smaller than the difference in solar radiation on the tilt angle. This implies the flexibility in designing the roof shape of solar houses.

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In this paper, the PV system in Kitakyushu Science and Research Park (KSRP) in Japan has been introduced. By analyzing the recorded data in 2002, the power generation result has been evaluated. On the basis of this, comprehensive module conversion efficiency for two different photovoltaic cells, single-crystal and multi-crystal, has been discussed. Furthermore, the factors influencing power generation amount and module conversion efficiency have been analyzed by using the single regression and the multiple regression method. And the environment contribution also has been evaluated.
The results can be summarized as follows: 1) Although the PV system has been responsibility for little part of power consumption at KSRP, it has high reliability and stable running situation. 2) The average hourly module conversion efficiency is 10.6%, about 74.1% of comprehensive conversion efficiency with 14.3%. 3) Irradiance is the most important influence factor on power output of PV system and almost in direct proportion with power generation amount. The influence from air temperature is important than the one from wind velocity on power output, but the influence from them are both very small. 4) PV system has contributed to reduce environmental load greatly.

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This paper presents a feasibility study of a fresh air load reduction system by using an underground double floor space. The fresh air is introduced into the double slab space and passes through the opening bored into the footing beam. The air is cooled by the heat exchange with the inside surface of the double slab space in summer, and heated in winter. Then the heat is transferred to the adjacent soil through foundation slab, wall and to the room just above the mat through floor slab. This system not only reduces sensible heat load of the fresh air by heat exchange with earth but also reduces latent heat load of the fresh air by ad/de-sorption of underground double slab concrete. In this paper, we used a model for evaluation of fresh air latent heat load reduction by hygroscopic of air to earth exchange system taking into account coupled heat and moisture transfer of underground double floor space. In conclusion it shows the validity of the proposed method for a design tool and the quantitative effect of the system.

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The purpose of this study is to provide the regional insulation criterion of earth-covered walls for underground residential buildings in Korea by using a numerical simulation program. This study was started from the idea that thermal condition of underground residential space must be closer to that of aboveground residential space. According to the result of this study, the underground temperature declines as the depth from the ground level goes deeper and closer to about 9m, and then maintain some steady value from about 9m of the depth. The minimum thermal insulation by depths was deduced by finding the U-factors that make the inside-surface temperature of the earth-covered wall closer to that of the aboveground wall.

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Condensation on the inside surface of the curtain walls of high-rise residential buildings is an important environmental problem in Korea. The purpose of this study is to introduce a new prediction method that can analyze the occurrence hours (days) of inside-surface condensation and compare with several design alternatives under a design stage, utilizing software codes developed by the authors according to the Korean standard, and numerical simulation models such as DOE, esp-r and so on.
The method consists of three parts; the first part is on a numerical simulation program that supplies the third part with input data such as weather data, indoor temperature, relative humidity and etc for 8,760 hours (8,760 hours = 1 year). Moreover, it can control building component, air-conditioning system, internal element like people, equipment and so on. The second part is on accurate U-values of the glass center and the glass edge that are received to the third part. The third part is on a software code to 1) determine the occurrence of condensation by the precedent procedure that calculates the inside-surface temperature and the dew-point temperature at the specific time and condition, and 2) sum up the occurrence hours (days) of inside-surface condensation. The application of the method is illustrated with an example of a high-rise residential building.

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The housing market in Korea is changing rapidly. As multi-functional high-rise residential complexes become popular, occupants need more comfortable indoor environment as well as more usable spaces than ever before. These trends force to increase the energy usage for environmental controls, especially for cooling. Thus, this study aims at reducing the cooling energy requirements of high-rise residential complex by maximizing the possibilities of natural ventilation strategies through cross ventilated Double Skin Façade. Based on ESP-r simulations, it was confirmed that the Double Skin Façade could reduce up to 30~40% of cooling energy compared to the conventional façade designs.

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This is a research by design project, made possible by a live project engaging a historic building on the University campus. The Eliot Hall was originally one of three residences for undergraduate students built in the nineteen thirties. The authors collaborated with the Estate Office and the User Center of Journalism and Media Studies to put in place their research agenda as ″Green Architecture - the Eliot Experiment 2001″ to study the following hypothesis: (1) passive environmental design strategies; (2) man-nature interactions; (3) user interactive controls of environmental performance; (4) green education. This paper underlines the process from design, construction, fitting out/re-modeling (completed in the Summer of 2003), and the setting up of a data monitoring and display system (Spring and Summer, 2004).

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In Kitakyushu Science and Research Park, a new district energy system has been introduced. In this study, we chose this system as a case study and have carried out an analysis on the efficiency of the power generation and heat release utilization of the fuel cell and gas engine in summer by using recorded data.
The results can be summarized as follows; 1) Although the power generation efficiencies of the gas engine and fuel cell are slightly lower than the standard designated value, they are almost constant throughout the period of study. 2) The collected heat energy is lower than the designated value. The heat release utilization, which is used for cooling and hot water, is lower than expected. Considering the efficient use of energy for such systems, it is important to have a good use of heat release when we introduce a district energy system. 3) The discarded heat energy of the system is very big in this investigation when evaluating the system as a whole. It is fundamental to the future of energy conservation to use primary energy more efficiently.

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In order to determine the factors of origin of Sick House Syndrome (SHS), data of indoor air quality in the sick houses and field survey were collected and carried out respectively, over three summer seasons from 2000 to 2002, from 35 houses where occupants are suspected of suffering from the so-called Multiple Chemical Sensitivity (MCS) and SHS, in the Miyagi prefecture of Japan. This survey consisted of the measurements of indoor air pollutants (the concentration of formaldehyde and volatile organic compounds (VOC)), air tightness and ventilation rate, together with questionnaire regarding environmental conditions, subjective symptoms and lifestyle. Medical examination was also conducted to residents having heavy symptoms. In addition, 15 houses out of 35 houses were investigated continuously for another two or three years.
As the results, the average values of formaldehyde concentration and TVOC of the investigated rooms from this study are 0.12 ppm and 1557 μg/m³, respectively.
The formaldehyde concentration in over 71% of rooms exceeds the guideline from the Ministry of Health, Labour and Welfare of Japan. While the VOC concentrations have been reducing, the formaldehyde concentration has hardly changed. The most frequently described symptoms are mucosal and respiratory symptoms (such as eye irritation, sore throat, cough). In addition, it is revealed that many patients are found having allergic diseases. The relationships between the measurement results of indoor chemical substance concentrations and the symptoms obtained from questionnaire, suggest that the symptoms become serious not only in the houses with higher concentration of TVOC, but also in the houses with lower concentration.

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The flow and dispersion around the obstacles is important to understand the pollution problem in the urban areas. This study presents the preliminary results of the experiment carried out at Dugway Proving Ground, Utah. It shows that the presence of obstacles has a significant effect on the structure of the plume. Both horizontal plume spread (σ_y) and vertical plume spread (σ_z) are higher in arrays of obstacles compared to without obstacle configuration. It is also observed that the concentrations in arrays of obstacles are generally lower than those without obstacles. The modeling results show that the Gaussian plume model for the time-averaged concentration in the near-field can provide important information with few input parameters. The information obtained from the controlled conditions of the model canopy can be useful for interpreting data from real urban areas.

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The main objective of this paper is to understand the aspect of residents′ community forming in planned detached housing areas, and then is to acquire a method for community planning based on characteristics of a housing area and its residents′ predisposition. For this purpose, an evaluation from the view of residents′ affection was employed. From the residents′ evaluation results and the evaluation structure of affection, the aspect that residents are forming community was clarified. Consequently, it was found that residents′ predisposition about neighbor relations influences the community forming, and some performance criteria and physical elements should be considered as important factors to community planning in planned detached housing areas.

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The purpose of this study is to establish a set of consistent guidelines for deciding entrance architecture of modern MRT (Mass Rapid Transit) stations in Taiwan, so that the details of construction, passenger circulation, and operation and maintenance procedures will be uniform throughout the entire MRT network. There exist the multi-criteria evaluation of subjectivities and externalities for the decision. To fulfill the interaction between subjectivities and externalities, we applied the appropriate ways, which included 1) the method of key-informant interview with decision-makers, professionals, experts and scholars to establish the multi-criteria, 2) the method of questionnaire and mathematical calculation to establish the weighting of each criterion, and finally applied 3) the method of multi-criteria evaluation with qualitative and quantitative data (MEQQD) for decision making. After the procedure of this study, it was found that ′site response′ was the most dominant criterion and the method of MEQQD could evaluate the alternatives to obtain the objective and appropriated consequence.

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This paper describes the very first effort to examine and verify teleworkers′ current physical environment in smaller scales and in broader aspects that have been neglected in existing studies. Through person-to-person and written surveys with Connecticut state government teleworkers, some significances of their physical environment were verified; In smaller scale of municipalities, they live significantly closer to the centers of their towns than national average, while in large scale, they clearly tend to live either in suburbs or in country side than in urban area. After they started telework, their neighborhood reliance in shopping and in service use noticeably increased shrinking the share of down town. Their houses are no larger than the average houses in the area, yet with their household size, majority of them can afford independent offices or large enough space to accommodate dedicated office space. At the same time, formal office, both as a room and as furniture setting, is not always desired. Some of these tendencies also found to correlate with their work-life factors such as telework frequency, their motivation to telework or their new way of time use.

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It is important to clarify how to apply urban design principles to protect areas within winter climates. Therefore, a question is addressed that do the blocks after infill developments provide desirable environment against snow, or not. The purpose of this paper is to answer this question and clear to understand the desirable block images for reducing snow problems (snowdrifts and snow blow) on its surrounding public spaces on infill developments in Winter Cities. Author studied the differences of the snow problems between ″before″ and ″after″ the infill developments consisted of medium-rise buildings in Downtown Sapporo on snow simulation tests using wind tunnel.
On this snow simulation tests, snow problems in the blocks and streets were improved after the infill developments. One of the main reasons of the observations is considered that the little variation of the building heights reduces snow problems on the public spaces in the blocks. For making the desirable spatial images in Winter Cities, the blocks have to be consisted of medium-rise buildings and unified the heights of buildings. The infill developments with medium-rise buildings with unifying building heights are effective against snow problems in downtown area, and making the desirable special block design for Winter Cities.

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This paper attempted the design method for the optimal parallel layout of Multistory Row House Clusters (MRHC) to maximize the overall quality of views from dwelling units with Genetic Algorithm (GA). The evaluation function of GA was designed based on the regression model established in our previous study. Five simulation models were executed respectively, which differed in the combination of Neighbor Blocks (NB) that MRHC faced and abutted. The optimal solutions to all the models can be sorted into similar three types of layouts which have common features such as: 1) improvement in the overall quality of views over the popular layout in the reality; 2) separated green lands inside MRHC; and 3) a not straightly aligned road. Furthermore, the discrepancy of the best solution in the models indicated that MRHC with different external surroundings demanded a different layout. Finally, the influences of the external surroundings on the quality of views in our model of MRHC were compared.

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This paper analyzes the relationship between livability and structure of two towns in Sumida city, Tokyo. Being historically and spatially contrasted despite located nearby, Kyojima and Honjo are comparatively analyzed under two different methods. According to a well-established topological analysis of city by Hillier (1998), Space Syntax′s Axial Map is applied to evaluate ′syntactic intelligibility′ and the degree of ′natural movement′ at both towns. Based upon ′Graph Geometry′ proposed by Nophaket (2004 a), the towns′ minimum-path structures are also detected. The network analysis applies Dijkstra algorithm to visualize the ′Network Pattern′ of street structure via C-language computer simulation (Nophaket, 2004 b). Comparison between topological-syntactic structure and geometrical-network pattern testifies not only significant contrasts in street patterns of Kyojima and Honjo, but also the different logic between two analytical models.
Whilst Axial Map specifically shows the quantitative correlation between ′integration value′ and pedestrian or vehicle flow rate on each straight line, the new Path Map of Network Pattern detects an overall ′qualitative pattern′, the organic grid of winding streets in particular. Importantly, it shows the vital linkage of city. This study can conclude that Space Syntax model based on depth analysis implies a macro structure of city. Network Pattern, by contrast, represents the metrical significance of street at a more detailed level.
The research findings, therefore, challenge an accepted generalization of applying Space Syntax across different cultures, archetypes and scales of street patterns. Moreover, it includes the geometrical analysis into basic graph-network study of urban form. As we believe, it is this metrical importance of street pattern that has been lost, perhaps not fully justifiably, within traditional Space Syntax analysis of the city.

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This paper analyzes and considers the main features of the Japanese avant-garde movement ″Metabolism″ that appeared on the scene of the architectural world in the early 60s. The originality of the concepts developed by its members and the innovative design of their projects captured the attention of many critics, in Japan as well as abroad, who often either misunderstood or neglected most of the original theories of the group. Therefore, it seems that furthermore analysis could be necessary to clarify some points of metabolist group′s activity, and to reach a better understanding of the historical context in which Metabolism has originated and developed, as well as of its aims.

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The authors created a hybrid analysis model with nonlinear discrete springs on an elastic half space in order to evaluate the nonlinear bearing behavior of soils. It is appreciated that their simulations realized the nonlinear behaviors to some extent. However, the discusser would like to discuss the following points in order to understand the research results more clearly.

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