This study is based on the assumption that there is a problem in the existing approach of introducing and applying the concept of metric weighting to space syntax. In this study, we discussed relevant previous studies to comprehend the problems and limits, established several new approaches for introducing and applying the metric weighting, and verified their validities by applying them to actual built spaces. We proposed the metric weighting functions of the distance itself, the square root function of the distance, the square function of the distance, the exponential function of the distance, and the logarithmic function of the distance to introduce and apply the metric weighting. We designated Myeong-dong, Insa-dong, and Seoul City Hall as the three target sites for analysis, and drew the respective segment axial maps representing the sites. Subsequently, we conducted metric segment analyses and correlation tests between the results and the pedestrian densities for the three sites, thus examining the predictive power against the human-movement behaviors.

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Traditional markets have played essential roles in local distribution in Korea, but such roles have declined as large department and discount stores have appeared, providing convenient parking and various services in new town centers. Dramatic changes in distribution, diet, and lifestyle are other reasons for the traditional market decline, which has also caused the local economies to decline. Recently, however, some traditional markets are trying to overcome these challenges through localized marketing strategies and improvements in traditional brands, marketplaces, product quality, and distribution efficiency. They are not only providing improved local distribution to residents and visitors, but are also promoting urban regeneration as cultural centers. This study analyzes traditional markets that successfully revitalized through various methods, conducts a literature review to investigate floor plans, photos, and statistical data, and creates case studies by visiting specific markets. We selected five successful traditional markets to study their utilization of space and revitalization methods. We also analyzed previous case studies similar to ours. We then selected a severely declining traditional market in a small city to analyze the status of its basic elements, such as its complex buildings, usage, and spatial characteristics, and finally, to propose a method to revitalize it.

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During the initial developmental stage of historical settlement, residents used the principles of feng shui to locate suitable residence sites to ensure quality of life. Using Huazhai Village in Taiwan as a case study, this study explores the design philosophy of ancient Chinese people through scientific analysis. Research showed that the region was characterized by a windy climate. Therefore, a computational fluid dynamics model was used to simulate the local wind environment and restore the early architectural complex of the village. Compared to the current situation, it was demonstrated that the planning principles of the early buildings gave first priority to site selection. Second, with the village streets acting as a wind corridor, the angle of the streets was well utilized to strengthen outdoor ventilation in summer. Third, according to wind field characteristics at different locations, various opening directions and arrangement modes were applied in different areas to improve the wind field of the living environment. This ancient ecological wisdom provides current designers with a new strategy for living in harmony with nature, which may aid the design of sustainable living environments that adapt to the climate.

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The elderly population in Korea has dramatically increased in recent decades. Since 1970, it has increased by 342%. In addition, housing needs of the elderly are becoming more diverse than in the past, in terms of household types, economic status, health status, education level, family relationships, and housing experiences throughout their lifetimes. Seniors expect to live in a housing option appropriate to their preferences. In reality, however, there is a lack of sufficient housing alternatives to suit their needs. Thus, various housing alternatives need to be developed to allow Korean seniors to live as they want. This study surveyed the opinions of researchers and facility staff in the field of elderly housing to identify the opinions of residents-related characteristics and to investigate current problems/difficulties and improvement needs of the social, physical, and management aspects. It can be useful information that can facilitate the development of alternative plans for elderly housing in the future. A questionnaire with open-ended questions was distributed to 50 housing researchers and facility staff members.

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The South Korean government is attempting to revive small supermarkets by branding them as ″Nadulgage.″ These efforts include support to change retail store signs; however, in reality, the government has only provided emblem designs thus far. Based on previous studies, this study reviews the current status and features of sign colors for both Nadulgage and convenience stores in the Jung-gu area. In addition, after analyzing color images using the Moon–Spencer Theory, PCCS tone chart and I.R.I Color Emotional Quotient as analysis tools, we compare the characteristics of Nadulgage and convenience stores and draw our implications. The colors of Nadulgage signs still display the characteristics of colors that were elucidated in previous research. Moreover, the dominant colors of Nadulgage signs have a higher ratio of colors belonging to the contrast area compared with those belonging to the other groups. This makes their impression confusing when compared with the impression of the colors of convenience store signs.
Therefore, reselection of the dominant colors that can portray the unique identity of a Nadulgage should be prioritized, and the color-matching relationship between dominant colors, assorted colors, and accent colors should be established in more detail. Thus, comparing Nadulgage and convenience stores may help in obtaining useful data.

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Only a few studies so far have analyzed specific environmental factors of cul-de-sacs′ influence on safety from crime. To understand crime, streets′ physical characteristics need to be considered along with the collective sociodemographic characteristics of each region. A model was designed that combines the physical characteristics of cul-de-sacs with the demographic characteristics of neighborhoods to examine the effect of such characteristics on the crime rate in cul-de-sacs. The physical characteristics of cul-de-sacs in a target area were categorized and examined based on connectivity, accessibility, and visibility, In addition to sociodemographic characteristics. A hierarchical linear model was then constructed from the collected data related to connectivity, accessibility, visibility, and sociodemographic characteristics at the neighborhood level. Finally, the results of the analyses were combined to determine their relationship with the crime rate. Except for a few variables, the results are significant for connectivity, visibility, and accessibility, which allows for an explanation of the occurrence of burglaries when sociodemographic factors are additionally accounted for.

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This series of studies investigated how ″Field of Experience,″ ″Semantic interpretation,″ and ″Group Communication Pressure″ influence the application of text-based design guidelines to graphic-based building designs, and cause communication failures during building permit review communication. In this first part, authors invited 16 experts in building design and divided them into four groups with similar fields of experience to assess design indicators by using the Fuzzy Delphi Method. The results showed that among various professionals, their varying fields of experienced caused design indicators to be assessed discrepantly. Authors plan to continue to explore how text-based design guidelines negatively influence communication effectiveness through semantic differences and group communication pressure and how to enhance communication effectiveness in the building design review processes.

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Through consulting literature discussing the specific military function of beacon towers, this paper classified the architectural forms of 116 beacon towers of the Ming Great Wall in Qinghai province, and determined their distribution characteristics. According to related documents, their architectural forms can be divided into six types based on the relationship between their stage body and circumjacent buildings (the moat, enclosing wall and small flint) with spotty and linear distribution features. To further explain the linear distribution characteristics, the concept of a beacon tower link was used to illustrate the military intelligence routes and transmission orientation of the intelligence system of the Xining Guarding Post during the Ming Dynasty. By researching the change rule of the beacon tower elevations situated on such links, the authors found that most of these elevations have decreasing trends along their military intelligence orientation. In addition, beacon tower links closely surround the Xining Guarding Post with a radial shape, and they follow some important river systems and ancient roads. Many links follow the rule that beacon tower elevations can change suddenly at the corners where they are located, which reflects the wisdom of ancient Chinese architectural design.

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In building information modelling (BIM), the amount of information increases and architectural design processes become more complex as projects expand. This is because while a collaboration environment is important for smooth communication among experts, this has not been realized because of unclassified file synchronization and permission settings among team members. Therefore, this study aims to support cooperation in BIM modelling projects by synchronizing BIM data from different computers and rendering BIM project management easier by providing a BIM model viewer and data through the Web. The proposed technology, which is a construction project-type, purpose-tailored browsing technology, provides BIM information related to construction environments and planning processes only to the relevant experts.

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This research aims to examine the historical evolution of the developmental housing system in South Korea, to elicit the characteristics of the system and to explore the structural forces realigning the system. The primary findings are as follows: 1) the Korean housing system strongly supports economic growth and has been formed by a state-controlled, market-driven, pro-homeownership policy, forcing housing to be highly commodified; 2) the state′s export-oriented, industrialization-led economic development prompted urbanization that resulted in a housing shortage, and the persistent demand for housing coupled with limited access to home financing caused housing prices to sharply increase; 3) democratization facilitated state-guided production of massive housing and provision of public rental housing which is residualised; 4) economic crises in the wake of economic globalization revealed institutional drawbacks of the developmental housing system and 5) the housing system has been ostensibly responding to political realignment, economic restructuring and socio-demographic transformation, leading to more variations in housing provision, particularly tenure mode, structure type, size and housing careers.

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Yogyakarta City has a sacred cosmological space formed by imaginary philosophical axes based on the centuries′ old Javanese belief system. The Kraton or Sultan′s Palace is the focal area with the space around the philosophical axes functioning as a buffer area, and the outer circle that serves as a supporting area. All are linked by the concept of co-habitation space.
This paper aims to explain the spatial, philosophical principles in relation to the phenomenon of changes in the urban space in Yogyakarta today. The concept of co-habitation space is physically understood as activities showing guyub (harmony/togetherness) carried out by urban citizens. These can be seen from place attachment, livelihood, and spatial territory. The focus of this research is the sharing phenomenon (′co′) that takes place in kampong (urban neighbourhoods) spaces and their surrounding areas.
This study uses a rationalistic approach and mixed methods of which the main methods employed were observation and space syntax. The results of this study suggest that the level of guyub in an area is influenced by the local spatial configuration. This study concludes that the concept of co-habitation space affected the way the Sultans of Yogyakarta utilized their kingdom′s territory for the welfare of their people.

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Quality function deployment and TRIZ method are widely used to develop new products in the manufacturing industry. These methods are known to be extremely effective for cost reduction and quality improvement. However, unlike the general manufacturing process, the manufacturing of an exportable modular building system involves many sub-processes that proceed concurrently. Therefore, there is a limitation on the efficiency that can be achieved if either of these methods is directly applied to product development. In order to address this issue, the authors propose a new methodology wherein quality function deployment is integrated into TRIZ. The results of a case study show that application of the new method makes it is possible to reduce the volume of an exportable modular building system compatible with ISO container shipping by 48% and to decrease the weight of structural steel by 30%.

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With increased attention being paid to Crime Prevention Through Environmental Design (CPTED) in crime-prone areas, a demo-project was mounted in Mapo-gu Yeomri-dong in South Korea to reduce crime rate and fear of crime. Preceding studies on the project have assessed only reduction in fear of crime, by surveying residents and non-residents; the present study uses actual incremental crime data from target areas before and after CPTED application to identify change in crime rate, using the quantitative analysis method WDQ. Results illustrate that theft decreased where CPTED was applied but increased in nearby areas, while violent crime increased in both types of area. These results show that CPTED reduces the rate of property crime but has no effect on violent crime.

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This paper aims to clarify what kinds of design elements in environments stimulate mental activity. The study examined the effects on brain activity when wearable optical topography was worn in different booths having different sizes and color environments. The subjects′ mental activity in the prefrontal cortex was measured during working memory tasks conducted in four kinds of different booth: a small white booth, large white booth, small yellow booth, and large yellow booth. Physiological and psychological analyses revealed the following results. 1) The large yellow booth activated mental activity the most. 2) The booth size and color of the booth have an effect on the information processing activity of information processing. 3) The size of the booth has an influence on the physiological state. 4) Activation of brain activity has an effect on the affected reaction rate and percentage of correct answers.

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Reading motivation and perceived quality of the reading space are considered to influence students′ affective responses in reading. This study chose college students as respondents because reading is part of daily learning activities. Reading activities emerge because of the students′ motivation to read. College students intentionally choose a reading space that complies with these activities. The aim of this study was to find the influence of reading motivation and perceived quality of the reading space on the students′ affective responses. Data collection was carried out based on an online survey questionnaire. Exploratory qualitative research was conducted to collect data based on information about the motivation and rationale for selecting a specific place to read. Explanatory quantitative research was conducted to interpret the causal relationship between reading motivation and perceived quality of the reading space towards students′ affective responses. The results showed that the perceived quality of the reading space was the more dominant factor influencing affective responses compared to reading motivation. The users assessed the quality of the reading space on the basis of the factors ″ease and comfort″, ″hustle″ and ″tranquility″. Furthermore, some reading motivations, i.e. the factors ″improve inspiration″ and ″entertainment″, affectively influenced the students′ thinking ability.

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This study investigates certain correlations between the impacts of urban and building form and microclimate on the energy consumption of buildings. It applies microscopic elements such as urban form and tissue, building form and character, and microclimate as factors in the energy consumption of buildings. To this end, the energy consumption of selected buildings in Seoul in August of 2014 was analyzed. Based on microscopic elements within a radius of 500 meters of 23 Automated Weather Station (AWS) measurement points selected by the Meteorological Office of the City of Seoul, the study employed both ordinary least square (OLS) and gamma regression, techniques that have been widely applied in this field of study. The analysis results show that compared to OLS, gamma regression is more suitable for analyzing the energy consumption of buildings. With the exception of a few elements, the urban form and character elements demonstrate a significant relation to the energy consumption of buildings. It is also found that microclimate elements such as wind speed and humidity are pertinent to the energy consumption of buildings. This study is expected to contribute to the foundation for the formation of sustainable and resilient cities through the reduction of energy consumption.

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The Hanoi ancient quarter is a district with 1,000 years of history, which has grown rapidly in recent years as an international tourism destination with its historical townscape as a tourism resource. Consequently, the business types have shifted toward tourism and with that town houses are being rebuilt and renovated, thereby changing the townscape. Surveys of changes to the townscape were conducted from 2003 through 2015 to grasp the actual conditions and causes of the changes, and to clarify the impact on the townscape. Among those, this paper analyzes data from 2003 and 2006 as the initial change, and reaches the following findings.
1) Not only is the tourism industry spreading, but also tourism shops are expanding to upper floors.
2) Rebuilding, renovation, and other changes with an impact on the townscape are taking place along with the shift of business type to the tourism industry.
3) Many of the rebuilding projects are for conversions into hotels.

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Depth reversal is the false perception whereby a receding or projecting spatial composition actually appears as the opposite of that composition. Such illusory effects are often forceful and have become a popular visual effect utilized in many site-specific installation artworks. However, the design approach most often employed is based on trial and error because the visual perception of depth-reversal illusion is often difficult to predict without actually seeing it in reality. Unfortunately, this approach demands extensive time and effort as well as increased material costs. Computer-aided design often provides a low-cost alternative for the design process; however, the feasibility of using a computer simulation in the design process depends upon the visual realism offered by the simulation. This study investigated the visual realism of a computer simulation with regard to envisioning the visual illusion of depth reversal. Perceptual studies were conducted to measure critical distances that occur when an observer experiences the visual perception of depth reversal in both physical and computer-simulated environments. The quantitative experimental results were used to establish the reliability of computer simulation for the design process of installation art that utilizes illusory visual effects of depth reversal from design ideation to exhibition planning.

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This paper presents a study of utilization and perceptions towards side setback areas as an important but often overlooked urban space. Side setback areas, which are mutual distances between adjoining buildings in a high density, inner-urban, residential area of Osaka, Japan were selected for study. Volunteers were interviewed in the Kita Nakamichi area to investigate the physical attributes of their side setback areas and their frequency of usage. There was little impression of side setback areas or windows opening towards them. They are seen only as mere left out spaces between the building and boundaries; however, the respondents did not have concerns about security.
On the subject of utilization of the side setback areas, activities such as storage and gardening were noted, as these places were seen as abandoned spaces but subject to considerable maintenance, and were suggested by a significant number of the respondents as good places for parking places, storing items and drying clothes due to receiving good light and ventilation. When asked about their preference for making contact with fellow neighbours via their side facades, respondents unanimously reported that they prefer to undertake social interaction at their front door and those accidental contacts are not favoured.

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Many cities around the world have experienced fast urbanization with suburban development. The organic urban forms of old towns or existing city centers have been extended with modern grid systems. However, little research has been conducted to identify the impact of modern grid forms on the organic urban structure in the city center. This study aims to examine the transformation of urban morphology using space syntax for the case study of Barcelona, Spain, which is an ideal case city because of its organic city center surrounded by an orthogonal urban system.
The result showed that at the car-oriented global scale, the city center area with an organic urban form loses its importance in terms of space syntax indexes such as choice and integration values. However, the organic structure becomes more important at the pedestrian-oriented local scale. Furthermore, adding the grid structure to the original organic form increases the relative importance of the organic form in Barcelona′s city center. This finding indicates that a grid system and an organic form are not in opposition to each other, but can instead be complementary. This study implies that the integration between organic form and grid system is very important and necessary for urban regeneration in many cities.

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Strong winds have caused an increasing amount of damage to fruit trees, such as uprooting and fruit drop, and various prop systems or support systems have been introduced to prevent this wind damage. When a prop system is designed against strong winds, it is essential to calculate the wind load acting on each tree in order to accurately assess the wind resistance of the prop system. In particular, the fluctuating effect is significant and cannot be ignored when the natural frequency of a tree is relatively small. In this study, vibration tests were performed to measure the natural frequencies and damping ratios of trees in order to evaluate the wind load acting on the trees. Both ambient and free vibration tests were performed, and the dynamic properties were identified and compared. It was found that the average natural frequency of trees was approximately 1.0 Hz, and therefore the dynamic effect against fluctuating wind load needs to be considered. The analysis results of the gust effect factor indicated that the wind load may be underestimated or overestimated considerably if the flexible nature of trees is neglected, or if the exact values of natural frequency and damping ratio are not available.

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This research focuses on multi-prime (MP) contracts, as an alternative contracting method to general contractor (GC) contracts, to reduce the construction costs of the Korean government. Two pilot projects were executed under MP contracts with direct owner management (without professional construction management services). The project performance (i.e., construction costs, schedule, defects and participant satisfaction) under the MP contracts was then compared with a GC contract. The results show that construction costs reduced somewhat but not as much as expected (8% reduction). Direct construction costs were also reduced using the lowest bid system, but indirect construction costs, such as common laborer costs, increased. Fast track construction was not applied to the pilot projects, and therefore their schedule and defects are not distinguished from those under a GC contract. However, project participant satisfaction is very high and participants stated they would use MP contracts again for future projects. These pilot projects show that the owner′s management ability is very important in MP contracts and directly affects project performance. Therefore, professional construction management services for owners in MP contracts are strongly recommended for successful projects.

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Lightweight concrete has been adopted to prefabricated elements such as facades, staircases and wall systems in housing projects. Many research have been carried out on production of lightweight panels without using ordinary portland cement. The objective of this experimental study was to develop construction materials applicable to lightweight wall system by using ground granulated blast furnace slag and paper ash, which are industrial by-products. Specifically, we carried out an experimental research on the properties of a lightweight matrix that could have application to lightweight wall systems without involving any use of Portland cement that emits massive amount of carbon dioxide (CO₂) from chemical process and burning fuel; the major culprit behind global warming. In this study, we used NaOH alkaline activator to achieve the strength of a ground granulated blast furnace slag-based matrix without using general Portland cement. As a result, the mechanism was uncovered as to how NaOH alkaline activator led to the generation of hydrogen gas through reaction with the unreacted Si of paper ash. In addition, we found that construction materials applicable to lightweight wall systems could be manufactured by using ground granulated blast furnace slag and paper ash, industrial by-products.

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Cardiovascular diseases loom large in China and studies indicate an appropriate luminous environment helps to boost the emotions of cardiovascular patients. This study discusses emotional and visual influences of the luminous environment of Cardiac Intensive Care Units (CICU) on both patients and medical care personnel. We draw the following conclusions: 1) Illuminance level, color temperature, and lighting method all affect patient and nurse satisfaction. 2) Patients prefer low color temperature, while nurses prefer a higher one; however, factors such as illuminance, lighting method, and luminance distribution outweigh the influence of color temperature. 3) The major factors affecting patient satisfaction consist of the emotional and the visual factors in inverse correlation. 4) Nurse satisfaction correlates to the visual factor score. 5) The visual factor scores of subjects (patients and nurses) correlate positively to illuminance levels and average luminance. 6) In a specific range, the visual factor scores of subjects correlate positively to luminance contrast and UGR. 7) In a scenario characterized by an illuminance of 200 lx or an average luminance of 60 cd/m², the trends of patients′ emotional factor and visual factor intersect, where the emotional factor peaks. 8) For the patients and nurses in CICU, their lighting demands varied due to different purposes. Patients needed to rest while nurses needed to see things clearly at work. In our opinion, the CICU Luminous Environment should be adapted to the needs of different major users (patients or nurses) with controlled parameters to achieve ideal performance. However, when illuminance and average luminance grow beyond the peak, the emotional factor will decrease.

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The authors evaluate indoor air quality in apartments built according to the South Korean Clean-Healthy House construction standard. The evaluation includes three types of residential units with differing gross floor areas. Indoor air was analyzed for formaldehyde (observed range 52.0–99.2 ug/m³), acetaldehyde (14.6–61.0 ug/m³), benzene (0.6–1.3 ug/m³), toluene (161.8–371.0 ug/m³) ethylbenzene (6.5–17.0 ug/m³), xylene (14.7–45.0 ug/m³), and styrene (37.7–112.5 ug/m³). The concentrations of all analyzed substances were within the South Korean guidelines. The findings confirm that the Clean-Healthy Homes initiative has led to a greatly improved indoor air environment compared to existing newly built apartment blocks in South Korea. However, this construction standard is applied only to large apartment developments comprising 1,000 or more units, and it seems that further effort should be made to extend the standard to stand-alone residences and small-scale apartment blocks in order to ensure that indoor air quality is maintained more widely.

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Nowadays, backflow odor, along with floor noise, has been recognized as an environmental right dispute element between the units within a multi-unit dwelling in Korea because it causes not only foul odors flowing back into the unit vent pipe to flow indoors and cause a problem of degraded air quality but also annoyance by foul odors and steam in balconies and bathrooms. Therefore, this study relates to the performance improvement of bathroom air duct facilities in multi-unit dwellings. This study aims to develop an automatic backflow preventive damper capable of reducing the air leakage rate in comparison to conventional air duct dampers and verify the backflow blocking performance of the automatic backflow preventive damper.
As a result, unlike the existing damper, where air in the space assumed a bathroom was foggy because of the large amount of air leakage, the dry ice gas did not flow backwards to the bathroom in the space, where the automatic backflow preventive damper was applied. In addition, it was verified that the automatic backflow preventive damper had an excellent air leakage blocking performance of 98.6% compared to the air leakage blocking performance (80%) of the existing damper.

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This study examines the ventilation function and economic feasibility of a combined air-diffuser ventilation (CAV) system, in which the exhaust air opening and the supply air opening are combined into a single module. A mock-up test and computational fluid dynamics (CFD) were employed to identify the properties of the CAV. The CFD was validated using a benchmark test and then used to investigate the ventilation function of a conventional ventilation system and the CAV using SVE3 and SVE6 for ventilation. The SVE3 and SVE6 results of the CAV were similar to those of the conventional ventilation system. The economic feasibility was assessed based on the duct length and the number of components. In comparison to the conventional ventilation system, the duct length decreased by approximately 68%, the number of dampers decreased by 50%, and the number of diffusers decreased by 40-50% for the CAV.

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Building heating, ventilation, and air conditioning (HVAC) systems contribute substantially to the energy consumption of buildings. Today, traditional HVAC systems mostly operate according to the maximum occupancy assumption, which in turn increases energy consumption during periods of low occupancy. Although, recently, implementing demand-driven HVAC operations are accepted as an innovate approach for reducing HVAC-related energy consumption, occupancy forecast is important to realize demand-driven HVAC operations in buildings. This study aims at using time series models in order to forecast the daily number of bank customers in a financial center of a bank, which is located in Izmir, Turkey. Data were collected from the computerized tracking system for a period of 60 weeks and two forecasting methods were used: 1) Decomposition Method, 2) Box-Jenkins Method. To determine the final model identified via the Box-Jenkins Method, goodness-of-fit, residual analysis and Akaike information criterion were taken into consideration. The results show that the SARIMA model with a MAPE of 11% yields a good occupancy forecast for supporting demand-driven HVAC operations.

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PVC floor material is widely used in Korean homes, and people customarily sit or lie on the floor surface. This could potentially put residents of such homes at high risk of exposure to semi-volatile organic compounds (SVOCs). However, there is a current lack of information regarding the degree of SVOC contamination in Korean homes. Therefore, this study was implemented to measure SVOC concentration in the air and house dust in homes and kindergartens, places where children spend long periods of time. The substances analyzed were 2E1H, D6, DEP, TBP, TCEP, DBP, TPP, DOA, and DEHP. Amounts of 2E1H, D6, DEP, DBP, and DEHP were detected in the air of the homes included in the study, and the average air concentrations of DBP and DEHP were 0.53 μg/m³ and 0.28 μg/m³, respectively. The average dust DEHP concentrations in the rooms of homes and kindergartens were 2,800 μg/g and 4,350 μg/g, respectively, showing that higher values were measured in kindergartens. The measured DEHP concentrations in the dust of both homes and kindergartens where PVC floor materials are used were high.

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The Helmholtz resonator (hereafter resonator) is qualified as a silencer with a narrow noise attenuation band at its designed resonance frequency. Combining several resonators in line is a possible way to produce a broader noise attenuation band. This paper focuses on improving the noise attenuation performance of a duct-resonator system at low frequency. Two types of periodic duct-resonator system are analyzed theoretically and numerically: a duct-resonator system with identical resonators and a modified duct-resonator system with periodic two-resonator arrays. The planar wave theory and the transfer matrix method are used to investigate wave propagation in the duct-resonator system. The theoretical prediction results yield satisfactory agreement with the Finite Element Method simulation results. The results indicate that both the periodic duct-resonator system and the modified duct-resonator system can broaden the noise attenuation band. Furthermore, the proposed modified duct-resonator system in this paper contributes to a relatively broader noise attenuation band than the periodic duct-resonator system. The modified duct-resonator system provides a useful method for the design of such a system, in order to obtain a relatively broadband noise attenuation.

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This study analyzes the impact of a windy environment on the ventilation rate and the thermal environment of a double skin façade (DSF). The wind profile was used to change the direction of the wind to the front, back, and side directions. Three cases were examined using computational fluid dynamics (CFD) analysis. There were two openings on the front of the DSF in Case 1, openings on the lower and front parts of the DSF in Case 2, and two openings on the front of the DSF for each story in Case 3. The results are as follows. 1) The front wind direction interrupted the release of the cavity′s interior air, and the ventilation rate decreased by an average of 47.6% in comparison to the results with wind from the side and back directions. 2) The ventilation rate was highest for the back direction in Cases 1 and 3 and for the side direction in Case 2. The ventilation rate of Case 3 was the lowest. 3) The total heat transfer rate of the highest story of the DSF was inversely proportional to the ventilation rate.

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