Hubbe House, designed by Mies van der Rohe in 1935, although not actually built, is significant in that it marks the first application of his theoretical idea of a court to an actual site. In the Hubbe House, Mies′s concept of a court, which he presented theoretically for educational purposes, was applied to build a practical and complex structure with consideration of site conditions and architectural ideas he had long sought to use. This paper interprets his idea concerning court in the following ways. First, as for its relationship with the interior space, the court has significance and effect as a method to make the relationship between the interior and exterior spaces more active. Second, the court prevents the view from extending beyond the site by means of intentionally devised obstructions. As a result, ″quiet seclusion″ is created in the court by blocking out the often hectic confusions of the outside world. Third, the court is designed to have both open natural scenery and closed artificial scenery, which are in contrast to each other, creating a harmonized composition of the building as a whole.

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This paper clarifies the locations, operation and system of the markets in Hue, the capital of the Nguyen Dynasty as well as the architectural form of the shops and background to the formation and spatial structure of the markets. The findings of this study are as follows: shops were partitioned by brick walls with three bays as a basic unit. The markets outside the citadel formed a linear spatial structure as they were constructed by improving the existing shops that had been built one after another by the citizens along the streets or constructed without destroying the residential areas that had shops along the streets. The markets inside the citadel formed a concentrated spatial structure as they were constructed after removing unnecessary facilities in newly developed blocks. Markets in Hue were located outside and inside the citadel respectively and consisted of a pluralistic system with domestic and trade markets as well as open and government-run markets. The tax revenues collected from the markets were used to help the poor, to maintain and repair various facilities, and to operate the army. Markets played a central role in the maintenance and functioning of Hue both as the capital and as a city.

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Recently, there have been various attempts to recover the quality of urban life. It is obvious that the problems of modern cities have brought a loss of living quality and the exclusion of inhabitants, but there has not been a proper evaluation of these attempts, due to the absence of a theory focusing on quality. This thesis attempts to turn Pepper′s ′contextual operation theory′ providing insight concerning quality into an urban theory based on Rossi′s urban thought, and confirm the values of the theory by applying it to Busan. The ′contextual operation theory′ is classified into three types; ′successful working′, ′verified hypothesis′, and ′qualitative confirmation′, and suggests possibilities for solving a problem correctly through ′qualitative confirmation′ which deals with quality and texture together. Furthermore, to deduce the quality and texture of an event, this theory suggests the necessity of qualitative circulations between hypothesis and perceptual experience. The similarity between the ′contextual operation theory′ and Rossi′s ′urban artifact′ confirms the possibilities of this theory as an urban theory. By roughly distinguishing areas in the city of Busan into three types based on this theory, the authors can estimate both a way in which quality is treated and a direction by which to recover it.

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The dynamic nature of the construction industry, rapidly changing global market environments, and lowest cost competitive bidding make it difficult to survive in global construction markets. To understand global construction markets and find success factors regarding a firm′s growth, this study was conducted to develop basic data related to establishing future business strategies for Korean firms by analyzing their current business strategies as well as other advanced firms in the global construction market. To select construction companies for a case analysis, construction firms listed in the ″Top 225 Global Contractors″ from Engineering News-Record from 1995 to 2007 were reviewed. The model of change of business structures was examined by selecting and classifying such firms using two analysis standards in terms of the size of revenues and competitors. It was found that those firms were proactive and responsive to changing markets by increasing their overseas revenues and enhancing their competency through more diversified products in order to stabilize their revenue structure.

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Louis Kahn′s architectural works embody his rational tectonic epistemological perspective by exhibiting the ways he respected the nature of construction materials and how he built his structures in accordance to how he believed that space, itself, desired to be portrayed. From the Exeter Library, which was completed in 1972, it is evident that Kahn integrates two different structural systems, bricks and reinforced concrete, into a design concept that exhibits his profound respect for the innate characteristics of the chosen construction materials and the space that they create. The current study focuses on the concept of spatial formation, structural systems, piping distribution, and their integration into the construction of Louis I. Kahn′s Exeter Library. A review of the literature is first presented, which is followed by a comparison and analysis of a number of various plans, and 3D simulation models of the project. The relationships existing between the methods that Louis Kahn employed and the nature of the materials he used during spatial formation are presented, which is followed by a description of how these techniques enabled Kahn to express his rational tectonic ideals in the integration of construction materials and piping distributions. It is shown, for example, that Kahn endeavored to integrate various types of piping distribution in relation to the demands of construction and structural forms. In this way, Kahn′s work interprets different characteristics of space in various types of architecture to display a rational tectonic method that responds to the form of a space.

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This study considers an agricultural land use plan using multi-agent simulation in the agricultural area of Nakhon Pathom Prefecture, Thailand, where small-scale croplands of various products exist. In formulating the simulation, interviews with farmers were conducted and a research index of the area was used so that the opinion of the stakeholders will be reflected in the plan. This study is comprised of the following research and analysis. 1) Interviews with farmers concerning future land use. 2) Field study of the size of the croplands and the kinds of products. 3) Construction of the simulation. 4) Calculation of the transportation distance, transportation cost and impact on the environment. As a result of the simulation to integrate the croplands of the same products, it was found that pursuing integration to the end does not necessarily reduce the transportation cost and environmental impact. It is effective to conduct integration while paying attention to the cost effectiveness.

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Successful green tourism approaches have been implemented in the Tianyuan District of Zhuzhou City for about 10 years. Recently, green tourism has been developing in order to improve the quality of tourism, with gaining attention from the green tourism administration, operators and visitors. In this study, the current state and development of green tourism in Hunan Province was examined. By taking on-site experiences and exchange activities at the green tourism sites as study examples, based on visitor and operator investigations, focusing on the key points of green tourism, especially based on on-spot investigation, the driving force of green tourism development, relationship between the green tourism administration, operators and visitors, and the development trend of green tourism in Hunan Province are summarized.

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This study examines and analyzes the current state of gardening facilities for residents in 11 senior citizen housing complexes and their understandings, actual gardening behaviors and their effects. The objective is to suggest a direction for the planning of gardening and its spatial composition in senior housing complexes. The study used surveys and interviews and conducted field visits to examine actual gardening facilities. The study produced the following outcomes. 1) Elderly people had high expectations that gardening would bring them ′mental comfort and physical health′. Though they are experiencing mental comfort, direct effects on physical health were not seen. 2) The common gardening space provided by the facilities subject to the research, were small in size compared to the number of residents and it was inconvenient since it did not take into consideration the characteristics of the gardening activities. 3) Elderly people found that gardening encouraged social interactions with other residents and enriched their daily lives. 4) Residents in senior housing complexes chose places as gardening spaces that are close to their flats, in particular their living rooms and on the same level for easy horizontal access. From the result of this research, it was clear that diverse gardening space should be provided for the residents to choose and freely express their individual characteristics. In addition, instead of providing a dedicated gardening space, a multipurpose area that could also be used for diverse hobbies was more practical.

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New residential needs have recently caused a construction boom in central areas of Japanese metropolises leading to population recovery and compact conversion in many cities, such as Kyoto. This study shows how central Kyoto has become compact by an investigation of condominiums. An evaluation of CO₂ emissions based on the supply of condominiums was carried out. The investigation shows that the supply of condominiums within the central district of Kyoto has been increasing faster than that in the fringe district recently. Travel distance and modes of transportation are changed by such compaction process. The estimation shows that compact housing arrangement, which shortens traveling distance and changes the transportation modes of residents, helps to reduce CO₂ emission in Kyoto. The results also indicate that, in the central district of Kyoto, the supply of dwelling units for households with more than two family members is more effective in reducing CO₂ emission.

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The objective of this study is to analyze the influence of landmark factors on the price of super high-rise residential buildings. The level of influence is analyzed by means of an hedonic pricing model. In this paper the height and area are identified as landmark factors in analyzing the landmark's influence quantitatively. Also, the concept of relative quantity is introduced regarding the height and area because the landmark factors involve comparisons with neighboring buildings rather than by the building's absolute characteristics alone. Relative height and relative area derived by such an approach were established as independent variables for the hedonic pricing model, along with conventional price-determining factors. Samples subjected to this analysis included thirty super high-rise residential buildings each containing at least thirty stories and all located in Seoul. Results from a linear regression model and a semi-log regression model revealed that p-values were less than 0.05, indicating that the regression coefficients of relative height and relative number of stories are significant.

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An essential component of spatial analysis travel is often inter-modal and any surface such as the ground, air or water can be a travel path depending on the travel mode. Current geospatial software, while offering various procedures for complex computation of travel costs based on different factors, can however become quite cumbersome, inflexible and limited in meeting a researcher′s needs especially when dealing with inter-modal travel. To more realistically capture this ground truth, simulation models need fast and efficient methods that take into consideration available travel modes rather than simple networks. An innovative approach for computing and visualizing optimal paths in inter-modal travel is proposed in this paper. A modified Accumulated Cost Surface method is used with several travel cost surfaces created based on the underlying topography and available modes of travel. Preliminary tests demonstrated a high level of success in computing travel time on actual road network data. This paper discusses the effectiveness and limitations of this method. Current findings suggest that this method might provide a convenient way for computation and visualization that is suitable for use in Web-based planning support systems.

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Existing research concerning construction change order claims deals primarily with system and external problems as the causes of such claims. This study aims at analyzing the attitudes of construction engineers regarding change order claims and makes suggestions for preventing them. Undesirable professional attitudes that may cause change order claims were defined and investigated, and suggestions for improvement solutions are made. To prevent change order claims, undesirable professional attitudes should be minimized, systems and environments should be improved appropriately, and new professional education systems should be established to train more ethical engineers.

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This paper attempts to clarify how employees choose individual workstations in a non-territorial office, in which they may locate themselves anywhere as they wish. The authors ascertained the preference of employees with regard to the positions of their workstations and the consistency of choosing the same workstations. The results are as follows: for all the investigated employees, there was a tendency to choose workstations that were adjacent to the main corridors and close to the meeting corners. More than 70% of the employees either chose the same workstation every time or nearly every time. In total, 90% of the employees were found to locate in the same or in adjacent areas. Analysis by group showed that while employees in the engineering groups, the renovation design group (Architecture Group 3), and the competition team were inclined to locate in specific areas and use such areas consistently, employees in the other architecture groups were much more open to choosing workstations far away from each other. Further, the analysis showed that leaders were inclined to occupy workstations beside the main corridor in the center of the office while ordinary staff members preferred workstations near the entrance.

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Street crimes such as auto theft and snatch theft account for approximately half of all crimes committed in Japan. The strategy of CPTED (Crime Prevention through Environmental Design) is now drawing the attention of urban planners and architects. Recently, the effectiveness of CPTED has been empirically examined using GIS. In this article, the authors investigate the relationship between snatch theft and the spatial attributes of the suburbs of Kyoto City. The spatial attributes considered include demographic data, land-use, visibility of space, and illuminance on the street. These attributes are analyzed with a significance test of mean as well as via CAEP (Classification by Aggregating Emerging Patterns). From these analyses, the authors obtain the following conclusions: (i) Mean values of pedestrians, population, and visibility of non-housing sites are relatively high at snatch theft locations. (ii) Illuminance on the street is not a predominant factor. (iii) Primary spatial patterns of snatch theft locations include relatively high visibility of a public facility site. (iv) The classification accuracy of CAEP is higher than that of other general classifiers. (v) In residential areas, the risk of snatch theft tends to be high only at particular sites. Meanwhile, downtown, it can occur frequently regardless of the site.

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This study clarified the corresponding relation between spatial elements and a subject′s psychological perception. The evaluation of subjects concerning open space could be generally divided into three factors. They are ″Activeness″, ″Amenity″ and ″Openness″. Also, according to the questionnaire survey results of 70 persons, the most popular waiting spaces in terms of function were ″A place to sit″, ″A place with shade″ and ″A place that is most visible to a friend″. However, according to the results of subjective evaluation, ″Bench″ and ″Emptiness″ had the worst evaluations regarding ″Activeness″ and ″Amenity″, indicating that although they met the functional demands of sitting when waiting or being seen by friends, they lacked surrounding feeling, and thus could not satisfy the psychological sense of security. In view of ″Tree″, it met the functional demands of shading in a subtropical climate; meanwhile, the surrounding feeling and shadow formed by its crown created a visual concealment effect, meeting the sense of security and became the most preferable waiting space.

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During the Japanese Colonial Period, the Japanese built many Japanese style houses in Taiwan. The residents of these Japanese style houses changed after World War II, but they were still used as residential houses. Starting in the 1990s, many of these houses have been dismantled because of obsolescence. This has also brought opportunities for conservation and reuse. However, there have been many diverse ideas for the redesign of Japanese style houses. It has been difficult to reach any consensus on the reuse of these houses. This study has proposed obtaining criteria weights by use of the Analysis Hierarchy Process, and has employed fuzzy set theory and TOPSIS to evaluate the performance of reuse design in actual cases. The results have indicated that using this method can integrate opinions from diverse personnel, so that the decision-making process on reuse design may be made smoother, and become comprehensive.

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In recent times, studies on the management and maintenance of facilities have increased in Japan. However, these studies focus only on residential buildings and private offices. As far as public facilities are concerned, the government is focused only on surveying the amount of stock and on the basic notion of maintenance. There is a lack of government initiatives for the maintenance of public facilities. Only regular maintenance can help in increasing the efficiency and life cycle of these facilities. Further, to solve the current problems such as energy crisis, CO₂ emissions and decreasing of tax revenue caused by an aging society, it is necessary to prolong the life cycle of public facilities and efficiently maintain them. This study examines the present state of management and maintenance of public facilities mainly focusing on the present conditions of municipalities receiving low financial support and compares the maintenance facilities of these municipalities. For this purpose, radar charts and the PPM matrix were used. It is found that even in badly supported districts, energy consumption and the number of facility users are high. Further, some municipalities are found to be efficiently managing the public facilities, and their management and maintenance skills are worth benchmarking.

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This paper examined the land use change (LUC) and sustainability index of major Chinese cities to develop a model for implementing more efficient land use and sustainable urban development (SUD) practices in China. The authors show that substantial LUC occurred across 29 Chinese cities during the 1990-2000 period. In particular, cities in the Yangtze River Delta (YRD), the Beijing-Tianjin-Hebei Area, and the Pearl River Delta underwent considerable LUC while achieving efficient land use. Characterization of the different LUC patterns of these cities revealed that land use efficiency differed between cities. The components of sustainability, including socio-economic, environmental and resource use indexes, were also clarified. Factors such as socio-economic development had the effect of increasing the sustainability scores of coastal cities relative to the scores of northern and industrial cities further inland. Regression analysis revealed which factors had the greatest effect on the level of environmental index. The results showed that industrial activities, population trends, and the pattern of land use all significantly affect the environmental component and SUD of cities. Finally, the network of cities in the YRD and a land use model in which cities undertake resource endowments, including land for improving SUD, was discussed.

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This paper is the second report following the ″Living Environment of Nomads Residing on the Outskirts of Ulaanbaatar, Mongolia.″ The series of this study aims to reveal characteristic tendencies in the perception of livelihood and activities and behaviors of the nomads and to study the relationship between the life system with fewer environmental burdens fostered in the traditional nomad society and their perception of livelihood and communities. Opinion surveys and interviews were conducted for nomads residing on the outskirts of Ulaanbaatar regarding their summer (August) campsites. A spatial configuration survey (measurement survey) of the groups (Khot-ail) formed by nomads was also conducted. The purpose was to consider the relationship between the living space and the unique lifestyle of nomads and their perceptions and activities, with the aim of obtaining basic knowledge regarding the creation of the unique nomad living environment. The results indicated that the sustainable lifestyle of nomads that is rooted in the characteristics of the natural environment is the result of the ″cooperative and cooperative labor″ quality of nomadic life, as seen in the daily life and leisure activities of nomads, and the ″flexibility″ of nomadic life, as seen in the mobility of nomads, the spatial configuration and household makeup of the Khot-ail and so on.

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Due to rapid changes in today's construction industry, the need for modification of laws and regulations has increased. First of all, the Ministry of Strategy and Finance of the Republic of Korea plans to modify contract laws and regulations for public sector projects. A thorough and comprehensive investigation of the US construction industry concerning the public sector will help the Korean construction industry make strategic plans toward amendment of laws and regulations. The primary purpose of this research is to investigate the project delivery method and contract administration systems for public sector projects of the US construction industry and to propose some suggestions to improve the current systems as found in the Korean construction industry. Through this investigation, various promotional issues as well as obstructions were identified by considering the differences in market conditions between the US and Korea. Frameworks of the suggestions provide for a consistent process of reinforcement of the owner's responsibility, and fair competition among construction companies.

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Globalization of architectural practices and fragmentation of knowledge are driving contemporary design studios to work within a dislocated net of partners. Consequently, the main point for successful remote collaboration is the understanding of team dynamics. During the first stages of a design activity, team members work, discuss and communicate multiple proposals in a dynamic and unclear way. Available software for teamwork assistance is focused on real time sessions, following the approach used for Product Development. However, remote collaboration in architectural design requires a specific approach supported by asynchronic collaborative visualization tools. This paper presents the Multi-dimensional Collaborative Debate Visualizer (MultiDCD⁺Visual), a client-server system for managing the flow of information in geographically distributed design teams. The system constructs a multi-dimensional model of the evolution of the design activity, allowing users to intuitively understand the debate of ideas.

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In the previous paper, a new analytical model was presented that incorporates ideas of network analysis and multi agent simulation. Also the advantages and potentials was discussed that could be achieved by combining those two methods. This paper looks at how the discussed potentials could be utilized in real situations. As a step of model application, this study focuses mainly on the reliability of the model in predicting actual pedestrian volume. A meso-scale urban district called Shimokitazawa in Tokyo, Japan was selected as the target site for analysis. To validate the reliability and efficiency of the model, this paper will take the following steps: 1) A pedestrian simulation will be performed based on the information collected from target area examinations. 2) The resulting outcome of simulation will be compared to the actual pedestrian volume data for correlation analysis. 3) The model′s reliability will be discussed from the correlation analysis result. If proved reliable through this procedure, the logical ground of further studies using the proposed model will be given. Moreover, the developed model will clearly become a useful analytical tool to assess and predict pedestrian movement in real situations.

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Empirical studies of human behavior have been developed mainly using methods of interview or questionnaire by researchers themselves. These studies have successfully obtained adequate results. To observe the behavior of many subjects at once, for many hours and in a wide area however, an alternative technological method is required. The purpose of the authors′ work is to develop a better objective method based on measurements, observations and experiments to clarify human behavior in urban environments. The purpose of this paper, as a first step, is to show the availability of research methods concerning children′s behavior after school in a suburban city district. The authors asked each primary schooler to wear a compact Global Positioning System receiver after school and to act casually. The collected spatio-temporal data using the Geographical Information System was also analyzed by developing a denoising technique. As a result, the authors clarified the behavior patterns of 35 primary schoolers′ regarding transportation devices, travelling routes, distances, time to arrive home and duration of outdoor activity. In conclusion, the authors showed the validity of a research method concerning the collective subjects′ behavior for a long period and in a wide area based on more reliable data using the Global Positioning System.

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This survey was conducted at Tainan station which is an At-Ground Station. The designation of the Tainan station as a historic site limits, certain changes to the structure such as re-constructed or extended. This study examined passenger behavior in this historic station and how management can design and locate effective information signs with limited operational funds. The three parts of the study were observation, post occupancy evaluation (POE), and interviews and questionnaires. The survey indicated that experienced travelers tend to enter the train station directly, read the A4 information sign to understand the train schedule, buy ticket at ticket vending machine, and then go directly to the platform. The survey results indicated that information signs close to ticket window (A1) should be replaced by information sign A4 which provides immediate information on schedules. This supports experienced travelers, who use information sign A4 most often. Management teams can use good graphic designs on walls and corridors as well as pavements and restrict advertisements to limited locations. Staff should provide temporary support or set up temporary, moveable information signs to guide train passengers. In the future, studies of train stations should investigate information signs to connect the traffic vehicles of its surroundings, and review further improvement for information signs of the station.

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Researchers and site engineers in construction have tried to develop appropriate methods of productivity measurements. Even though many methods have been released in academia and industry, they seldom are able to select the optimized method while considering various site conditions. This study was developed from a previous study which presented the quantified productivity differences on one specific operation, that of the conventional earthmoving operation. This study suggested more consistent results for productivity differences by various methods while focusing on two different operations; the conventional and the GPS-based system. This study verified the findings from a previous study whereby results from a deterministic method and an actual measurement yield the highest values and the lowest values, respectively. It was also found that the quantified differences were mostly within 10% of the range of productivity loss in the deterministic measurement, which was illustrated in the literature. Additional statistical verification showed that the differences were mostly within 95% of the confidence intervals. It is expected that this study will provide researchers in academia with basic guidelines for developing appropriate methods for performance measurements. This study also assists site engineers in the construction industry to predict productivity and to convert results to more realistic values by using methods other than actual measurements.

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As with other types of architecture in the process of modernization, Taiwanese school buildings entail a basic problem that must be resolved – ″what type of architectural form″ is capable of representing modernized school architecture. This paper uses the creation and identification of ″cultural symbols″ as themes, first organizing the close relationship between the development of Taiwanese architectural forms in different periods and symbolism; then, for the post-921 earthquake period, a number of aboriginal elementary schools located in mountainous villages in Taiwan are used as case studies to demonstrate that Taiwanese aboriginal school buildings have already developed from the shallow and crude operations of image symbolism to ″space type″ analogized architectural models. Then, case analysis is used to show that forms derived from cultural prototypes have different degrees of perception due to different autonomous identification and conversion methods applied by architects to cultural symbols.

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This study aimed to analyze spatial changes and structural transformations in five Korean mega-cities using populations and the number of tertiary industrial workers as variables. The authors grouped together and chose to study five mega-cities, Seoul, Busan, Gwangju, Daegu, and Daejeon, in Korea. Previous studies only focused on one city or region, thus offering a limited analysis. This study used the data from the Population and Housing Census, performed in Korea in 1995, 2000, and 2005. The authors also used the number of tertiary industrial workers from the Census on Basic Characteristics of Establishments in Korea for the years 1995, 2000 and 2004. Three methodologies were used to analyze spatial structural changes in the five mega-cities: 1) induction transit density analysis to separate city centers from sub-centers, 2) spatial statistics using the Gini coefficient and the standard distance to measure concentrations and dispersions of populations, and 3) spatial analysis to identify the effectiveness of spatial changes using the inverse distance weighting (IDW) method in GIS. The features of the five mega-cities can be summarized as follows. First, there was suburbanization and concentration of the populations, and second a spatial de-correlation between the population and the establishments.

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This study had the aim of explaining the mechanisms of autonomous spatial recomposition of shophouses in Phnom Penh (Cambodia), along with understanding the current status of spatial recomposition of these dwellings based on a field survey. Four detailed case studies were chosen for analysis and it was discovered that three points can be raised as causes for spatial recomposition: (1) securing living space, (2) securing independence and (3) changes in access method and four locations can be raised as spacial recomposition locations: (a) dwelling unit interior, (b) residential block interior, (c) city block space and (d) space between residential blocks. In addition, the results of analysis of 60 buildings and 74 dwellings showed 289 spatial recomposition locations. In particular, it is characteristic that there are a high number of extensions to residential block interiors and many instances of privatization of corridors, addition of kitchens/bathrooms, interiorization of terraces and construction of small rooms on roofs can be seen. By organizing the spatial recomposition methods, it was discovered that eight ways exist: (1) stacked layer, (2) installation of interior floors, (3) addition of kitchens/bathrooms, (4) appropriation of space outside the dwelling, (5) fencing in space, (6) closing of stairways, (7) installation of stairways, and (8) removal of walls.

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This study proposes a simple method of analyzing the road network factors and evacuation choices of residents in case of an earthquake. Using questionnaire survey data from Shin-Hua, Tainan County Taiwan, this study uses 6 indexes to evaluate shelter safety and applies a spatial statistic model with Local Indicators of Spatial Association (LISA) as an index to the evacuation choice of residents. Firstly, factor analysis is used to find the key factors affecting shelter safety, and cluster analysis is used to classify attributes. The final results with quantified indexes are then depicted in GIS maps for urban planning.

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There has been a lot of controversy about whether the return on IT (Information Technology) is adequate. While the number of articles on IT evaluation has been substantial, limited attention has been given to the value of an intangible benefit. This paper aims to suggest an approach to putting a financial estimate on the intangible benefit of IT applications. The authors' chose a sample system for the evaluation and utilized the contingent valuation method to quantitatively measure the intangible value. Then, a valuation and analysis model were suggested for the quantitative valuation of the intangible benefit from IT adoption.

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The friction at the steel-concrete interface on the boundary layer that occurs during the flow of a fluid concrete in a drain plays an important part in its pumpability. These frictions are directly related to the composition of the formed boundary layer which depends on the concrete composition parameters. In order to highlight the relationship between concrete composition and friction interface, the authors initially developed and validated an apparatus called tribometer allowing them to make steel-concrete interface friction measurements and deduce interface parameters. Its' simple use at building sites enabled the authors to study the influence of the concrete composition on the resulting interface friction and its parameters, namely, viscous constant and interface yield stress. The results show that the increase in the cement paste volume, the water per cement ratio and the proportioning in superplasticizer support the concrete pumpability. The increase of the fine sand quantity in concrete induces negative effects on the interface frictions and on pumpability.

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It is important to control outdoor airflow rates into HVAC systems in terms of energy conservation and healthy indoor environment. Technologies are being developed to measure outdoor air (OA) flow rates through OA intake louvers on a real time basis. The purpose of this paper is to investigate the airflow characteristics through an OA intake louver numerically in order to provide suggestions for sensor installations. Airflow patterns are simulated with and without electronic air velocity sensors within cylindrical probes installed between louver blades or at the downstream face of the louver. Numerical results show quite good agreements with experimental data, and provide insights regarding measurement system design. The simulations indicate that velocity profiles are more spatially uniform at the louver outlet relative to between louver blades, that pressure drops imposed by the sensor bars are smaller with sensor bars at the louver outlet, and that placement of the sensor bars between louver blades substantially increases air velocities inside the louver. These findings suggest there is an advantage to placing the sensor bars at the louver outlet face.

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In this paper, an economic analysis of systems adopted as the perimeter zone system in office buildings such as convector, fan coil unit(FCU) and fan powered unit(FPU) was performed, with the variable air volume(VAV) system applied in the interior zone. The initial cost of each alternative, such as the construction cost of the air conditioning system, was determined by planning and design, and energy cost as running cost was calculated on the basis of the energy consumption of each system using a computer simulation. Economic analysis was performed using life cycle cost(LCC), with the present value method for the air conditioning system in the perimeter zone. The results show that FPU is the most economical air conditioning system. When VAV is applied to the interior zone, LCC of the FCU is reduced by 6% and the cost of FPU is reduced 9% less than that of the convector system.

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This paper proposes an adaptive outdoor reset control based on a fuzzy target temperature gap for a hydronic radiant floor heating system. A hydronic radiant floor heating system has nonlinear characteristics, such as the effect of time delay and temperature inertia. In hydronic radiant floor heating systems, a heating source system, such as a boiler, has a target temperature gap determined by nonlinear characteristics. An unadjusted target temperature gap causes the indoor temperature to fail at tracking the desired level, and results in many wide swings in room temperature. For these reasons, the hydronic radiant heating system has lower energy efficiency than is desired. To solve these problems, a fuzzy system is employed to find the dynamic target temperature gap of the hydronic radiant floor heating system under both indoor and outdoor temperatures. The fuzzy target gap temperature can determine calorie supply time and On-Off time. The obtained control system shows effectiveness compared with a classical On-Off controller. Simulational results are provided to illustrate the control performance.

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The SARS virus began to appear and spread in North America and Southeast Asia in the early 2000′s, infecting and harming many people. In the process of examining the causes for the virus, studies on the airborne pathogen SARS virus and the way it spread were carried out mainly in the medical field. In the field of architecture, studies were done on the diffusion of air pollutants in buildings using gases such as CO₂, N₂O, or SF₆, but research on virus diffusion was limited. There were also explanations of only the diffusion process without accurate information and discussion on virus characteristics. The aim of this study is to analyze the physical characteristics of airborne virus, consider the possibility of using a coupled analysis model and tracer gas for analyzing virus diffusion in building space and, based on reports of how the infection spread in a hospital where SARS patients were discovered, analyze infection risk using tracer gas density and also diffusion patterns according to the location and volume of supply diffusers and exhaust grilles. This paper can provide standards and logical principles for evaluating various alternatives for making decisions on horizontal ward placement, air supply and exhaust installation and volumes in large hospitals.

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