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Bisphosphonates are well-known drugs as inhibitors of bone resorption acting on inducing programmed cell death of osteoclasts. However, many in vitro studies report that optimal concentration of the bisphosphonate affects not only osteoclasts but also osteoblasts, that is, it induces the anabolic effects of osteoblasts. Recently reported 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) is an endogenous ligand of peroxisome proliferator-activated receptor-gamma, with an inhibitory activity on bone loss. Researchers have also suggested that 15d-PGJ2 has the ability to reduce bone destruction and as the possibility of regeneration of bone. The purpose of this study is to demonstrate the anabolic effect of two anti-resorptive materials, alendronate and 15d-PGJ2, in a critical sized segmental defect model of rat fibula. The regenerated bone on the operative site was assessed through gross, radiographic (plain X-ray, and micro-computed tomography), histomorphologic evaluation, and statistical analysis. Consequently, the locally applied alendronate prevented resorption of grafted materials, and had a positive effect on bone regeneration with positive micro-architectural modification of the surrounding bone, although this study did not verify a significant capacity of bone regeneration of 15d-PGJ2 and instead only shed a light on its possibility.

Traditional decibel-based measures in predicting annoyance from construction activities are limited to reflect high acoustic variability of construction machinery noises. Hence, a multidimensional approach based on perceptual attributes and psychoacoustic parameters is proposed. In-situ audio-visual recordings of 16 construction machinery in operation were evaluated subjectively on both perceived annoyance and a 12-item semantic differential perceptual attribute scale. The 16 machinery noises formed three clusters based on four perceptual components (Incisiveness, Strength, Intermittency, and Periodicity) derived via principal component analysis of the perceptual attributes. Notably, individual perceptual components strongly correlate with mean values of psychoacoustic parameters (loudness, sharpness, roughness, and fluctuation strength) over time, which we use to develop an annoyance model for construction noise. Both loudness and fluctuation strength were critical parameters to discriminate between clusters. The model can be used to automatically categorize construction noises by cluster and manage it based on known cluster characteristics. Ministry of National Development (MND) National Research Foundation (NRF) Submitted/Accepted version This work was suported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2022R1C1C1008066 and NRF-2021R1A2C1095819). This research was also supported by the National Research Foundation, Singapore, and Ministry of National Development, Singapore under its Cities of Tomorrow R&D Program (CoT Award: COT-V4-2020-1).

Although hospitals are notorious for poor acoustics, the acoustic environment is usually evaluated in silos, without considering other indoor environmental quality (IEQ) factors. In the absence of qualitative evidence, it is important to first establish a holistic baseline perception of the hospital acoustic environment before commissioning costly measurement campaigns. A psychometric questionnaire based on the industry-standard IEQ survey and ISO 12913-2 soundscape standard was administered to examine the perceived indoor acoustic environment quality across major occupant groups (i.e. staff, patients, visitors) in an acute hospital in Singapore. Of the 16 IEQ factors examined, all occupant groups expressed the greatest dissatisfaction with noise levels and sound privacy. Notably, the staff were significantly more dissatisfied than the other groups in terms of sound privacy and overall IEQ. When assessing the overall quality (OQ) and appropriateness (OA) of the acoustic environment, OQ was similarly neutral across all groups, whereas the staff expressed significantly lower OA than both patients and visitors. The dissatisfaction in the acoustic environment could be attributed to the perceived dominance and annoyance of vocal and operational sounds across all occupant groups, as well as the environment set-up with most being housed in cohort rooms. Particularly, the staff were significantly more annoyed with vocal and operational sounds than patients and visitors. This study also yielded evidence that challenges the validity of the 5-item Weinstein noise sensitivity scale when used in an Asian context, as well as the applicability of the perceived affective quality circumplex model in ISO 12913-3 for indoor environments.

This study aims to assess various perceived adverse effects of noise on construction sites according to the different stages and machinery used in the stages, and to examine whether or not personal-situational factors affect the judgment of managers regarding the adverse impact of noise at work through a self-reported survey method. Four primary construction stages and twenty-four types of construction machines were evaluated. The effects of personal (noise sensitivity) and situational (types of jobs, and years of working) factors on the adverse impacts of noise on annoyance, work performance, work safety, and speech interference at work were examined. The results show significant differences in perceived noise annoyance in the various construction stages. The demolition stage is the most annoying, followed by the foundation, earthwork, and concrete framing stages. In addition, the annoying equipment differs for each construction stage. A breaker, pile driver, and hammer compactor are rated as the most annoying construction machines in the demolition, foundation, and earthwork stages, respectively. Individual noise sensitivity appears to have the most significant influence on the adverse impacts of noise on annoyance, work performance, work safety, and speech interference. A high noise sensitivity group tends to judge construction noise to be more adverse than the rest. In addition, different interrelationships between the adverse items of noise are found across their types of jobs: building construction, civil construction, and safety management. The findings of this study will provide further knowledge to facilitate better noise management planning on construction sites. Accepted version This work was supported by a 2017-Research Grant from Youngsan University (2018000288), Republic of Korea.

With the advent of virtual reality (VR) technology, spatial audio has been increasingly adopted to evaluate the acoustic environment in soundscape research. It is therefore imperative to assess the quality of commonly used spatial audio reproduction methods to determine their ecological validity. Through subjective evaluations with 30 participants, the same participant evaluated four outdoor in situ locations vis-à-vis its corresponding audio-visual recording in VR on a separate day. A total of three spatial audio reproduction methods were assessed in VR, and they were all down-mixed from the first-order ambisonics (FOA) recordings to headphone-based FOA-static binaural, FOA-tracked binaural; and FOA 2-dimensional (2D) octagonal speaker array. The participants evaluated the acoustic environment in terms of the overall soundscape quality and perceived spatial qualities at each location. Regarding overall soundscape quality, there were no significant differences in evaluating the sound-source dominance and affective soundscape qualities between in situ and all VR methods. However, significant differences were found in the perceived spatial qualities between three reproduction methods and in situ. Among the source-related spatial attributes, the perceived distance of the dominating sounds was farther in the virtual than in the in situ evaluations. In the localization of sound sources, both the FOA-tracked binaural and the FOA-2D speaker array exhibited higher spatial acoustic fidelity than FOA-static binaural. Regarding the environment-related spatial quality attributes, the 2D speaker array reproduction was perceived as more immersive and realistic than other reproduction methods. Overall, the FOA-tracked binaural appears to exhibit sufficient fidelity for cinematic VR evaluation of soundscapes. NRF (Natl Research Foundation, S’pore) Accepted version

This study presents a new perspective on interrelationships among spatiotemporal patterns in soundscape, acoustic and urban morphological indicators. Spatiotemporal characteristics of soundscapes in a multifunctional urban area of Seoul, Korea were analyzed. Physical acoustic and perceived soundscape data were collected during three different daytime sampling periods. Urban morphological indicators representing building, road, open public space, and water feature components, were analyzed to quantify urban textures. Spatial and temporal factors were found to play critical roles in urban soundscapes. Regarding spatial patterns in soundscapes, urban soundscapes were characterized based on the main function of spaces. The temporal variability of soundscapes in urban spaces depended on diurnal patterns in perceived sound sources. Particularly, the perception of birdsong and sounds from human activities showed considerable variation across urban spaces. In addition, significant correlations were found among the spatiotemporal patterns in soundscape, acoustic and morphological factors. Based on the acoustic and morphological indicators, pleasantness and eventfulness models were proposed and the results indicated that the pleasantness model explained 50% of the variance, while the eventfulness model only predicted 13% of the variance. The results from the present study showed that urban morphological factors could be useful indicators for better understanding soundscapes in urban environments.

Noise maps based on sound pressure levels are limited in accurately representing how people perceive the sound environment. As a complementary approach to noise maps, soundscape maps can be useful tools for urban planning and design because they provide more information than conventional noise maps to reflect perceived acoustic environments. This study provides an overview of soundscape maps and explores the influence of spatial contexts on soundscapes in urban spaces. Physical, acoustic, and perceptual data were collected on sound environments in various urban areas in Seoul to create soundscape maps. Sound source types (traffic noise, human sounds, water sounds, and birdsongs), psychoacoustic parameters (loudness and sharpness), and perceived soundscape quality maps were generated and it was found that soundscape characteristics were varied in accordance with the primary functions of a space. Based on the collected soundscape data, global and local spatial regression analyses were conducted to examine the spatial autocorrelation on prediction on soundscape quality, and spatial dependency of soundscape quality was found in both models. In particular, a local spatial regression model based on geographically non-stationary relationships in variables was found to be more effective in understanding soundscape quality in multi-functional urban spaces. These findings could provide useful knowledge for soundscape planning strategies.

Before introducing natural sounds to potentially improve the soundscape quality, it is important to understand how key contextual factors (i.e. expected activities and audio-visual congruency) affect the soundscape in a given location. In this study, the perception of eight natural sounds (i.e. 4 birdsongs, 4 water sounds) at five urban recreational areas under the constant influence of road traffic was explored subjectively under three laboratory settings: visual-only, audio-only, and audio-visual. Firstly, expected socio-recreational activities of each location were determined in the visual-only setting. Subsequently, participants assessed the pleasantness and appropriateness of the soundscape at each site, for each of the eight natural sounds augmented to the same road traffic noise, in both audio-only and audio-visual settings. Interestingly, it was found that the expected activities in each location did not significantly affect natural sound perception, whereas audio-visual congruency of the locations significantly affected the pleasantness and appropriateness of the natural sounds. Particularly, the pleasantness and appropriateness decreased for water sounds when water features were not visually present. In contrast, perception with birdsongs was unaffected by their visibility likely due to the presence of vegetation. Hence, audio-visual coherence is central to the perception of natural sounds in outdoor spaces. Ministry of National Development (MND) National Research Foundation (NRF) Accepted version This research is supported by the Singapore Ministry of National Development and the National Research Foundation, Prime Minister’s Office under the Land and Liveability National Innovation Challenge (L2 NIC) Research Programme (L2 NIC Award No. L2NICCFP2-2015-5). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not reflect the views of the Singapore Ministry of National Development and National Research Foundation, Prime Minister’s Office, Singapore.” The first author was supported by the 2017 Lee Kuan Yew Postdoctoral Fellowship (Grant No.: 50025000).

This study focuses on how urban functions influence the soundscape in streets by exploring associations among human behaviors, soundscape, acoustic indicators. On-site soundscape assessments were conducted in eight urban streets located in Seoul employing a soundwalk method. The eight streets were classified into two place functions: central business district (CBD) and commercial areas. Through the soundwalks, acoustic recordings and perceptual responses to soundscapes in the streets were collected. As a human behavioral indicator, crowd density was calculated in the streets. The results showed that place function plays a critical role in soundscape evaluation in urban streets. Pleasantness decreased with increasing Eventfulness on streets in CBD. In contrast, Pleasantness had a positive correlation with Eventfulness on commercial streets. This difference in the correlation could be attributed to the difference in the compositions of sound sources between central business and commercial areas. Traffic noise was the most dominant sound source in CBD, which increased Eventfulness and decreased Pleasantness of the soundscape in the streets. Meanwhile, sounds from human activities contributed to an increase in both Pleasantness and Eventfulness in commercial streets. Predictive models of soundscape reflecting the contexts of CBD and commercial streets were developed using acoustic parameters and crowd density. In the context of CBD, acoustic parameters describing spectro-temporal characteristics of traffic noise were important indicators, whereas crowd density was found to be a critical indicator to predict soundscape in the commercial streets. These findings could help in better understanding the relationships between the soundscape and place functions in urban streets.

Classifications of heavy-weight floor impact sounds based on subjective responses were suggested by conducting two experiments. First, statements describing perceptual acoustic qualities related to floor impact sounds in residential buildings were collected and assessed with respect to the degree of annoyance levels. Equal-appearing interval scaling for indicating level of annoyance caused by floor impact sounds was then created using these statements. As a next step, heavy-weight floor impact sounds with different LA,Fmax and temporal decay rates (DRs) were evaluated in terms of annoyance using both the Likert scale and the equal-interval statement scale in laboratory conditions. Five categories for heavy-weight floor impact sounds were suggested based on the annoyance responses. The extent of acoustic comfort in each class was clearly captured by the statements related to the range of LA,Fmax for each class. Effects of DR and noise sensitivity on the classifications were significant. Differences between the class criteria for impact sounds with DR 60 dB/s and 30 dB/s were approximately 5 dBA. In addition, significant differences were found between the high and low noise sensitivity classification groups for impact sounds in the 50–60 dBA range.

Many studies have investigated the effects of water sound on soundscape with an assumption that target noise coincides with the masker (co-location), while no attention has been paid to spatial separations between target noise and water sound sources. This study aims to explore the effects of spatial separations between target noise and water sound on perceived loudness of target noise (PLN) and overall soundscape quality (OSQ) through laboratory experiments. Traffic noise (target) and a water sound (masker) were recorded as acoustic stimuli and a spherical panoramic video recording of a water fountain was also used as visual stimuli. The audio-visual stimuli were reproduced through a virtual reality head-mounted display and a multichannel ambisonic loudspeaker setup. The traffic noise and water sound were played simultaneously at various azimuthal separations and were combined with a panoramic recording of a water fountain as visual stimulus. Participants assessed the audio-visual stimuli in terms of PLN and OSQ. The effect of the spatial separation between the traffic noise and water sound was significant in both PLN and OSQ. Specifically, the PLN increase at 135° separation was equivalent to an estimated target noise level increment of ~1–2 dB. Similarly, the OSQ decrease at 135° and 180° separation was equivalent to an estimated target noise level increase of ~2–5 dB. Since the typical field of view of users in space is less than 135°, the results suggest that placing water features within a user's field of view could achieve better soundscape.

Because the acoustic environments of construction sites include multiple noise sources from various construction machines, it is necessary to consider the influence of combined noise on annoyance. The aim of this study is to examine the effects of the acoustic characteristics of combined construction noise on annoyance. Six construction machines, including machines for foundation work (pile drivers, earth augers, and payloaders) and demolition work (breakers, bulldozers, and excavators) were selected as noise sources in construction sites, and auditory experiments were designed to quantify the annoyance caused by the machines' individual and combined noise. The results show that both individual and combined noise correlate well with the equivalent sound level (LAeq), but that the annoyance caused by combined noise is significantly higher than the annoyance caused by individual noise when LAeq increases over 65 dBA. Among the psychoacoustic measures, loudness is the most important in determining the annoyance caused by individual noise, whereas both loudness and roughness significantly impact the annoyance caused by combined construction noise. Ranges of an optimum stationary-to-mobile machine noise ratio between two construction machine noises are suggested to minimize the annoyance caused by combined noise. Optimum stationary-to-mobile machine noise ratio ranges usually include 0 dBA when reference construction noise levels (e.g., pile driver or breaker) are lower than 60 dBA, whereas the stationary-to-mobile machine noise ratio should be greater than 5 dBA as construction noise levels exceed 65 dBA. These findings provide useful information to establish effective noise management plans for combined noise sources in construction sites.

This study aims to investigate relationships between soundscapes and landscapes within various functions of space, and to examine the influence of functional aspects of places on soundscape perceptions in urban environments. Surveys were conducted to assess soundscape and landscape perceptions in 25 locations in Seoul. Urban contexts were classified into four categories based on main functions, activities, and visual properties of the spaces: commercial, residential, business and recreational. A structural equation model of urban soundscape was constructed using seven factors, namely sound sources (traffic, human, and natural), pleasantness and eventfulness, visual quality, and the harmony of the environment. The model appropriately fit the data measured in the survey. The results showed that dominant factors affecting soundscapes differed in accordance with the main functions of the place. In commercial areas, sounds from human activities played a significant role in evaluating soundscapes. For residential and business functional areas, traffic noise was a dominant sound source influencing the soundscape quality. In addition, human sounds from leisure activities played an important role in constructing a relevant soundscape in urban recreational areas. The findings of this study provide an empirical evidence for understanding the holistic relationships among soundscape factors in urban contexts and demonstrate that functions of place should be taken into consideration as an important context for soundscape design.

The aim of this study is to classify the soundscape characteristics in urban parks based on perceptions of acoustic environments and to examine useful acoustic indicators to identify soundscape classifications. Both acoustic measurements and subjective evaluations of the soundscape were conducted at various locations in three urban parks. Using hierarchical cluster analysis (HCA), the soundscape perceptions in urban parks were classified into three clusters characterized by the dominance of sound sources, such as traffic noise, natural and human-made sounds. Both discriminant function analysis (DFA) and artificial neural network (ANN) analysis were performed using various acoustic parameters to discern which of them best differentiate the soundscape classifications in urban parks. It was found that the indicators representing sound strength (LAeq), perceived pitch sensation (τ1) and strength of the pitch components (Φ1) of sound scenes could effectively identify the clusters. In particular, autocorrelation function (ACF) parameters τ1 and Φ1 were significantly correlated with identification of traffic noise and human sounds. It was revealed that sounds caused by various human activities in parks play an important role to influence eventfulness of soundscape perception. Soundscape perceptions were also closely correlated with esthetic quality, simplicity and sense of enclosure of landscape. Despite the fact that the results might be limited to the local conditions in Seoul, the findings could provide useful information for designing appropriate soundscapes in urban parks.

In the present study, rural soundscapes with high-speed train noise were assessed through laboratory experiments. A total of ten sites with varying landscape metrics were chosen for audio-visual recording. The acoustical characteristics of the high-speed train noise were analyzed using various noise level indices. Landscape metrics such as the percentage of natural features (NF) and Shannon's diversity index (SHDI) were adopted to evaluate the landscape features of the ten sites. Laboratory experiments were then performed with 20 well-trained listeners to investigate the perception of high-speed train noise in rural areas. The experiments consisted of three parts: 1) visual-only condition, 2) audio-only condition, and 3) combined audio-visual condition. The results showed that subjects' preference for visual images was significantly related to NF, the number of land types, and the A-weighted equivalent sound pressure level (LAeq). In addition, the visual images significantly influenced the noise annoyance, and LAeq and NF were the dominant factors affecting the annoyance from high-speed train noise in the combined audio-visual condition. In addition, Zwicker's loudness (N) was highly correlated with the annoyance from high-speed train noise in both the audio-only and audio-visual conditions.

As concerns on the adverse effects of noise pollution in the environment grow, the use of environmental noise barriers has increased. Noise barriers are commonly considered to be public structures that affect landscape quality. Hence, both acoustic and landscape issues need to be taken into consideration to design effective noise barriers in urban environments. This study aims to investigate the intersensory perceptions of noise barrier performance in terms of the spectral characteristics of noise reduction combined with visual impressions of five different barrier types: aluminum, timber, translucent acrylic, concrete, and vegetated barriers. Illustrations of five barrier types were taken in a real urban environment, and the noise reduction characteristics of these five barrier types were predicted based on their acoustic characteristics. Noise annoyance, preconceptions regarding the noise attenuation performance of the barrier, the esthetic preference, and the overall preference for noise barriers were assessed through laboratory experiments. Three different types of experiments were conducted: audio-only experiments, visual-only experiments, and audio–visual experiments. The results of the experiments revealed that noise reduction, particularly low frequency components, had a dominant effect on the perception of the noise-attenuating performance of barriers. The preconceptions of noise attenuation by barriers affected the overall preference for noise barriers at 55 dBA, while esthetic preferences for noise barriers were significant at 65 dBA. In addition, barriers covered with vegetation increased the perceived noise barrier performance with increasing esthetic preference and preconceptions of noise reduction.